142 results
Search Results
2. It's not just a piece of paper: University education signals status and personality.
- Author
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Costa, Tainah P. de P. and Castro, Felipe N.
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PERSONALITY , *SOCIAL status , *FORM perception , *SOCIAL influence , *UPPER class , *FIVE-factor model of personality , *OPENNESS to experience - Abstract
The attribution of status carries significant social and reproductive advantages as it reflects individual qualities. However, the traits conveyed and those perceived do not always align with reality. It is crucial to understand how the status associated with different professions can influence the perception of traits, as it assists in decision-making during social interactions. This study aimed to investigate whether the status derived from university education influences the assessment of social status, mate value and personality traits among Brazilians. A quasi-experimental design with nonrandom assignment was used, employing online questionnaires administered through Google Forms. A total of 252 participants, both male and female, over 18 years of age, and residing in Brazil, took part in the study. These participants evaluated the social status, mate value, and personality traits of stimulus subjects with high and low-status university education. The results revealed that stimulus subjects with high-status university education were regarded as possessing higher status in society and scored higher on Dark Triad traits. In contrast, stimulus subjects with low-status university education were perceived as having greater agreeableness, emotional stability, and openness to experiences. In conclusion, university education signals social and personality traits, serving as a parameter to shape social perceptions. • Subjects with high-status backgrounds are rated higher on Dark Triad traits. • Low status indicates greater agreeableness, emotional stability, and openness. • University education serve as an indicator of social and personality traits. • University education affects the perception of the individuals in social hierarchy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
3. WASP (write a scientific paper): The ongoing process of ethical decision-making in qualitative research: Ethical principles and their application to the research process.
- Author
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Farrugia, Lorleen
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QUALITATIVE research , *TECHNICAL writing , *FORM perception , *HUMAN research subjects , *QUANTITATIVE research - Abstract
The nature of qualitative research is fundamentally different from quantitative research. In depth understanding and exploration of specific phenomena or their significance usually involve a data collection process with a select few participants with whom the researcher interacts over an extended period of time. The participants are not anonymous to the researcher and they also reveal personal information. Research participants' rights need to be protected, even more so in this type of qualitative work. This chapter discusses how ethical decision-making needs to be ongoing during the research process by applying the principles of respect for persons, beneficence and justice. Respecting research participants, involves addressing issues related to informed consent, anonymity and confidentiality while also reflecting on the researcher's impact on the participant and the research context while the research is carried out and also when the research is disseminated. The second principle of beneficence calls for the researcher to ascertain that participants' safety is given utmost importance. Finally, justice refers to ensuring that the burdens and benefits of research are shared fairly without any form of discrimination or manipulation. These principles offer the researcher flexible tools to reflect on ethical decisions as they arise throughout the research process. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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4. Effects of within-trip subjective experiences on travel satisfaction and travel mode choice: A conceptual framework.
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Lim, Tommy, Thompson, Jason, Pearson, Lauren, Caldwell Odgers, Joanne, and Beck, Ben
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TRAVEL hygiene , *SATISFACTION , *CHOICE of transportation , *PLANNED behavior theory , *FORM perception , *PSYCHOSOCIAL factors - Abstract
• People have cognitive and affective responses to stimuli during travel. • These responses are mediated by appraisal and are highly individualised. • Within-trip experiences affect travel satisfaction, attitudes, and mode choice. • Naturalistic research can elucidate the individuality of within-trip experiences. • Understanding individuality is needed for equitable active travel modal shift. Modest shifts from car use to active travel can result in substantial health, emissions, and economic improvements that result in cleaner, greener, and healthier cities. To achieve modal shift towards active travel, the transport field has long considered how psychosocial factors outlined by theories such as the theory of planned behaviour underpin travel mode choice. Recent models of travel behaviour detail how travel satisfaction – a person's cognitive and affective evaluations of their travel – influences mode-related attitudes which in turn influences desires and intentions to use a specific travel mode. In this conceptual paper, we introduce the concept of within-trip subjective experiences – cognitive and affective responses to individual events and stimuli during travel – and propose potential mechanisms for how within-trip experiences affect travel satisfaction and mode-related attitudes. Specifically, people have emotional and cognitive reactions to individual stimuli (e.g., near miss incident, pleasant scenery, heavy traffic) which are mediated by the process of appraisal. Over the course of a trip, the sum of these subjective reactions form the basis of their within-trip experience, which heavily shape perceptions of travel satisfaction and subsequently influence attitudes and intentions to use a specific mode. Furthermore, within-trip subjective experiences to stimuli potentially modify the beliefs that mode-related attitudes consist of, further highlighting the importance of considering within-trip experiences to individual stimuli for understanding travel behaviour and mode choice. The consideration of within-trip experiences highlights the individuality of peoples' responses to stimuli. Understanding and addressing this individuality and the unique needs of all potential user groups may assist in achieving mass modal shift towards cycling and active travel. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Characterization of EJ-270 and Ce-doped LiCAF scintillators for the development of high-rate neutron reflectometer detectors.
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Wen, Xianfei and Hayward, Jason P.
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NEUTRON counters , *FORM perception , *NEUTRON capture , *PHOTON counting , *NEUTRON flux , *SCINTILLATORS , *THERMAL neutrons - Abstract
The Second Target Station of the Spallation Neutron Source at Oak Ridge National Laboratory is anticipated to provide a neutron source with ∼20 times increase in peak brightness than the First Target Station. The neutron reflectometers currently in operation at the First Target Station need to be upgraded due to the increased neutron flux. A prototype neutron detector module based upon a pixelated scintillator array readout by silicon photomultipliers is being developed to address the high-rate challenge faced with future neutron reflectometer instruments at the Second Target Station. Two types of scintillator materials were considered for this detector development, i.e., 6Li-loaded EJ-270 plastic scintillator and Ce-doped LiCAF single crystal. This paper reports the scintillator characterization results, including light yield, pulse shape discrimination performance, capability to detect thermal neutrons in a high γ-ray field, and γ-ray sensitivity. The number of photons produced per neutron capture by EJ-270 and LiCAF:Ce was measured to be 2176 ± 91 and 2651 ± 108, respectively. EJ-270 demonstrated a good capability to discriminate between neutrons and γ-rays by employing the commonly used charge comparison method (figure-of-merit: 1.13 ± 0.01 for an energy cut of 292–426 keVee) and a reasonable performance when using the time-over-threshold techniques; however, no discrimination was observed from LiCAF:Ce regardless of the pulse shape discrimination approaches utilized, making pulse height discrimination necessary for LiCAF:Ce to differentiate between neutrons and γ-rays. Both EJ-270 and LiCAF:Ce exhibited an acceptable capacity to detect thermal neutrons at high exposure rates up to approximately 584 mR/h. The γ-ray sensitivities measured with a60Co source at an exposure rate of around 1145 mR/h were determined to be (6.11 ± 0.87) × 10−6 and (7.64 ± 1.08) × 10−7 for EJ-270 and LiCAF:Ce, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Development of a phoswich detector utilizing bismuth germanate crystal scintillator and polyethylene naphthalate scintillation film.
- Author
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Jeong, Dongwoo, Hur, Jiseong, Kothan, S., Kaewkhao, J., and Kim, H.J.
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SCINTILLATORS , *FORM perception , *DETECTORS , *NUCLEAR physics , *BISMUTH , *POLYETHYLENE - Abstract
In this study, we present the development of a phoswich detector system employing a Bismuth Germanate (BGO) crystal scintillator in combination with a Polyethylene naphthalate (PEN) film plastic scintillator. Phoswich detectors can contribute to various applications, including radiation monitoring, medical imaging, and nuclear physics experiments, due to their ability to discriminate between different types of radiation. The thin PEN film is sensitive to α and β radiation, while the BGO scintillator exhibits good γ radiation detection efficiency. The incident radiation type and its energy can be determined by analyzing the difference in decay times between these two scintillators. This paper presents an analysis of the detector's response to α , β , and γ radiation, and the particle tagging efficiencies are to be over 99.9%, 92%, and 99.8%, respectively. • We observe effective discrimination based on alpha, beta, and gamma characteristics. • The signals from BGO and PEN film fit well through pulse shape discrimination. • The tagging efficiency for alpha, beta, and gamma are over 99.9%, 92%, and 99.8%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Vacillant planning for creating green cities: The empirics of urban greenery in Kumasi, Ghana.
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Okyere, Emmanuella Abena Bemah and Asibey, Michael Osei
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CITIES & towns , *URBAN planning , *ECOLOGICAL houses , *SUBURBS , *ATTITUDE change (Psychology) , *FORM perception - Abstract
Greeneries contribute enormously to the health and physical wellbeing of individuals and sustainability of cities. This notwithstanding, greeneries in African cities have significantly declined over time. There have thus been several calls, notably, to plan for and create green cities by incorporating greeneries in homes and urban neighbourhoods. Achieving this requires local understanding, acceptance and positive attitudes of residents toward planning for and integrating greeneries in homes and the environment. There is however dearth of research in Ghana on the knowledge and willingness of households and city officials to plan for the creation of green cities as well associated barriers. This paper responds to this gap by employing the multi-case approach, comprising of two suburbs (a high- [Nhyiaeso] and low-income [Aboabo] neighbourhoods) in Kumasi, Ghana. A total of 380 households and various relevant city planning agencies were engaged in semi-structured interviews. The findings show considerable but variegate understanding of green cities, which is influenced by several factors such as study community, residency status, housing typology and educational attainment. Most households in both communities indicated their willingness to incorporate greeneries in homes and neighbourhoods. However, resource constraints, nonchalant attitude of some residents and poor maintenance practices, were reported as major barriers that impede the efforts to incorporate greens in homes and communities. Several recommendations are proffered. The study concludes that promoting and achieving the benefits of green cities can be shaped by the knowledge of it; hence, the need to consciously and continually educate households on their importance. • Greeneries contribute enormously to health and physical wellbeing of individuals. • There is considerable but variegate understanding of green cities. • Perception of individuals shape attitudes toward greening homes. • Residents showed willingness to incorporate greens in homes and neighbourhoods. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Pure CaF2 crystal for fast neutron detection.
- Author
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Quang, Nguyen Duy, Quoc Hieu, Phan Bao, and Kim, Hongjoo
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NEUTRON counters , *FAST neutrons , *LUMINESCENCE spectroscopy , *FORM perception , *ALPHA decay , *NEUTRON capture , *NEUTRON generators , *SCINTILLATORS , *CESIUM isotopes - Abstract
Pure CaF 2 crystals have been widely used for optical functional crystals due to their good optical properties, mechanical properties, and chemical stability. This study discovered the crystal's pulse shape discrimination (PSD), proving it a promising scintillator for fast neutron detection via the 40Ca neutron capture reaction. Luminescence emission spectra were studied by X-ray luminescence measurements. The maximum emission peak was observed between 250 and 300 nm, corresponding to self-trap exciton emission. The crystal response to gamma, alpha, and neutron were studied under 137Cs, 241Am, and 252Cf radiation sources, respectively. The difference in gamma and alpha decay times enabled the PSD capability of pure CaF 2. Large neutron reaction cross-sections, PSD capability, and good chemical stability make pure CaF 2 crystal candidates for fast neutron beam monitoring detectors. Moreover, the crystal can be used for 40Ca(n,p)40K and 40Ca(n,α)37Ag neutron capture cross-section study. • The paper reports the first study of pure CaF 2 crystal for fast neutron detection. • Light yield of the crystal is 7100 ± 700 photons/MeV. • The crystal has good linearity response, energy resolution is about 9.1% at 662 keV. • PSD was studied for gamma-alpha (FOM = 0.85) and gamma-neutron (FOM = 0.80) separation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. EvalViz – Surface visualization evaluation wizard for depth and shape perception tasks.
- Author
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Meuschke, Monique, Smit, Noeska N., Lichtenberg, Nils, Preim, Bernhard, and Lawonn, Kai
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DEPTH perception , *FORM perception , *VISUALIZATION , *TASK analysis , *TASKS - Abstract
• We extend our tool focusing on the evaluation of depth perception to include the evaluation of shape perception. • We extend the generation of task-based experiments based on vascular surface models to arbitrary surfaces models. • We provide an automatic preparation of web-based studies to evaluate depth and shape perception in visualization techniques. User studies are indispensable for visualization application papers in order to assess the value and limitations of the presented approach. Important aspects are how well depth and shape information can be perceived, as coding of these aspects is essential to enable an understandable representation of complex 3D data. In practice, there is usually little time to perform such studies, and the establishment and conduction of user studies can be labour-intensive. In addition, it can be difficult to reach enough participants to obtain expressive results regarding the quality of different visualization techniques. In this paper, we propose a framework that allows visualization researchers to quickly create task-based user studies on depth and shape perception for different surface visualizations and perform the resulting tasks via a web interface. With our approach, the effort for generating user studies is reduced and at the same time the web-based component allows researchers to attract more participants to their study. We demonstrate our framework by applying shape and depth evaluation tasks to visualizations of various surface representations used in many technical and biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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10. Performance stability of plastics for neutron-gamma pulse shape discrimination.
- Author
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Zaitseva, Natalia, Carman, Leslie, Glenn, Andrew, Kim, Yongwook, Ford, Michael, Eccleston, Gracie, Hurlbut, Charles, and Shipp, Kyle
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NEUTRON counters , *FORM perception , *LIQUID scintillators , *FAST neutrons , *THERMAL neutrons , *BIODEGRADABLE plastics - Abstract
The introduction of the first commercially available plastic scintillators with pulse shape discrimination (PSD) offered by Eljen Technology marked progress towards potentially replacing liquid scintillators in neutron detection. However, use of these plastics over several recent years has revealed an important flaw in these materials: the eventual degradation of scintillation light output and PSD performance. Studies described in this paper considered possible reasons for this degradation. Experiments conducted with numerous lab-prepared and commercial EJ-276 samples showed that the main factor affecting the instability is oxidation that involves highly reactive radicals generated during the polymerization process or from the further breakdown of polymer chains under oxygen/air exposure. Based on the obtained results, the stability of scintillation performance for PPO (2,5-Diphenyloxazole)-based PSD plastics has been improved through modifications of the composition via the utilization of scintillation dyes and compounds with antioxidant properties that diminish the effects of oxidation. Elements of these studies were used in the commercial production of the most recent EJ-276D PSD plastic version for fast neutron detection and 6Li-loaded plastics for thermal neutron and antineutrino detection applications. Performance projections of the new PSD plastics indicate a likely degradation of less than 10 % over 5–10 years in comparison to previous EJ-276 that might lose up to 30–40 % of the scintillation light during 1–2 years of storage or deployment under ambient conditions. • Degradation phenomena studied in Pulse Shape Discrimination (PSD) plastics. • Oxidation found to be the main reason for degradation of scintillation performance. • Stability improved using dyes and additions with antioxidant properties. • Results applied to commercial production of PSD plastic scintillators. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Experimental study of plastic scintillators array for compact fast neutron-gamma dual-modality imaging system.
- Author
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Shuai, J., Zhang, Y.L., Wei, Z.Y., Guo, Y.P., Fang, M.H., Guo, Y., Wen, X., and Zhang, X.
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IMAGING systems , *SCINTILLATORS , *FORM perception , *FAST neutrons , *GAMMA rays , *PLASTICS - Abstract
In a compact multi-radiation imaging system, the substitution of traditional charge-coupled devices with a plastic scintillators array coupled with silicon photomultiplier detectors significantly enhances the radiation tolerance of the detection and imaging module, thereby reducing the system footprint. We present a detailed structure of a compact fast neutron/gamma-ray dual-modality imaging system based on a plastic scintillators array and evaluate its performance in imaging various samples. The detector array consists of nine 14.7 × 14.7 × 100 mm3 EJ-276 plastic scintillators coupled with corresponding silicon photomultiplier units, arranged in a 3 × 3 grid. The usage of EJ-276 plastic scintillators allows for discrimination between neutron and gamma signals through pulse shape discrimination techniques, enabling data separation between neutrons and gamma rays. In this paper, we present the experimental procedure and results of fast neutron-gamma imaging for objects containing aluminum and polyethylene materials. Fast neutrons and gammas are delivered by an Cf-252 source. The experimental results demonstrate that the system achieves dual-modality grayscale imaging and has resolution for sample thickness. Reconstructed image contrast allows qualitative differentiation of sample materials, especially detecting low-Z materials encapsulated by high-Z materials. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Enabling pulse shape discrimination with commercial ASICs.
- Author
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Leland, John, Fang, Ming, Pani, Satwik, Venturini, Yuri, Locatelli, Marco, and Di Fulvio, Angela
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FORM perception , *SCINTILLATORS , *APPLICATION-specific integrated circuits , *NUCLEAR physics , *CHARGE transfer , *NUCLEAR nonproliferation , *SIGNAL processing - Abstract
Fast electronic readout for high-channel density scintillator-based systems is needed for radiation tracking and imaging in a wide range of applications, including nuclear physics, nuclear security and nonproliferation. Programmable electronics, like FPGAs and ASICs, provide a fast way of conditioning and processing the signal in real time. In this paper, we present a pulse shape discrimination (PSD) method based on the shaping circuit of a commercially available ASIC, the Citiroc1A by CAEN Technologies. We used two different shaping times per detector channel to calculate a shaping parameter that enables PSD. Using our new method, neutron and gamma-ray pulses detected by a d 12 -stilbene scintillator can be effectively discriminated at light output values greater than 0.15 MeVee. While not achieving the PSD performance of traditional offline charge integration, our method does not require the transfer of data to a separate system for further processing and enables the direct deployment of high-channel density multi-particle detection systems. Moreover, the availability of a wider range of shaping times than those on the Citiroc1A can potentially further improve the PSD performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. Growth and characterization of 6LiI:Ag crystal scintillators for thermal and epithermal neutron detection on the lunar surface.
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Quang, Nguyen Duy, Vuong, Phan Quoc, Luan, Nguyen Thanh, Truc, Lam Tan, Ton, Nguyen Duc, Kang, S.C., Park, Hwanbae, Nam, Uk-Won, Park, Won-Kee, Sohn, Jongdae, Choi, Young-Jun, Youn, Sukwon, Ye, Sung-Joon, Kim, Sunghwan, and Kim, Hongjoo
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NEUTRON counters , *THERMAL neutrons , *LUNAR surface , *SCINTILLATORS , *LUNAR surface vehicles , *FORM perception - Abstract
• 1.0-inch diameter 6LiI:Ag crystals were successfully grown using Bridgman method. • The maximum neutron-gamma PSD figure of merit was obtained to be 1.3. • Energy resolution of the thermal neutron peak of 12.0% can be observed. • 6LiI:Ag is promising neutron detectors in high neutron-gamma mixed fields. This paper discusses crystal growth and characterization of 1.0-inch 6LiI:Ag scintillators for thermal and epithermal neutron detection on the lunar surface as part of the Lunar Vehicle Radiation Dosimeter project. Zone purification method was employed to purify the raw material of 6LiI, and the crystals were grown using the Bridgman method. X-ray luminescence spectrum was measured to confirm the presence of Ag+ in the crystal lattice of 6LiI. The feasibility of neutron detection under 252Cf fast neutron irradiation was investigated. A hydrogen-rich paraffin wax moderator was used to slow down fast neutrons to obtain thermal and epithermal neutrons. The charge comparison method was used to perform pulse shape discrimination. The maximum value of the Figure of Merit was obtained to be 1.3, which demonstrates the capability of using 6LiI:Ag crystal scintillators in high neutron and gamma mixed fields. The energy resolution of the thermal neutron peak varied with the thickness of scintillators, achieving 12.0 % for the 0.5 cm thick samples. The potential for further improvement of the scintillation performance of 6LiI:Ag crystal relies on reducing impurities and color centers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. Design and performance evaluation of a compact thermal and fast neutron spectrometer.
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Li, JunYu, Fan, Peng, Zhu, ChengLin, Wang, MengMeng, Wei, ZhiYong, and Xia, Yan
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NEUTRON counters , *NEUTRON spectrometers , *THERMAL neutrons , *FAST neutrons , *SCINTILLATORS , *FORM perception , *STANDARD deviations - Abstract
Measurement of the space neutron radiation environment has put forward new requirements for the miniaturization and lightweight design of neutron spectrometers. In this paper, a compact broad-spectrum neutron spectrometer was designed, in which the fast neutron detector was based on the EJ-254 scintillator-coupled with SiPMs array, and the thermal and epithermal neutron detectors were based on the NaI(Tl + Li) (NaIL) scintillator coupled with SiPMs array encapsulated in Al and Cd shells, respectively. The overall weight of the neutron spectrometer was only 2.4 kg, and its dimensions were 154 mm × 123 mm × 115 mm. The fast neutron energy spectrum was obtained based on the capture-gated method and the Maximum Likelihood Expectation Maximization (MLEM) unfolding algorithm; the counts of thermal and epithermal neutrons were obtained based on the optimized frequency-domain Pulse Shape Discrimination (PSD) method and cadmium difference method. The proposed neutron spectrometer with all applied methods was tested as a whole system with a252Cf and a241Am–Be source. The spectrum result was compared to an ISO standard source. The accuracy of fast part of 0.5–10 MeV was 5.9% in definition of Relative Root Mean Squared Error (RRMSE). The thermal and epithermal neutron counts were far higher than standard spectrum, and we proved it being effected by laboratory introduced neutron scattering through a simulation, thus the thermal and epithermal flux measurements was believed to be decent. The Figure of Merit (FoM) of the NaIL's PSD neutron gamma discrimination were 2.57 and 2.90 respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. Turning opposition into support to immigration: The role of narratives.
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Cattaneo, Cristina and Grieco, Daniela
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IMMIGRANTS , *FORM perception , *EMIGRATION & immigration , *CONFIRMATION bias , *NARRATIVES , *INTERNET surveys , *LABOR mobility - Abstract
The way we collectively discuss migration shapes citizens perceptions of migrants and their influence on our society. This paper investigates whether a narrative about the positive impact of immigrants on the hosting economy affects natives' behaviour towards migrants. To shed light on the underlying mechanism, we present a simple theoretical framework that models the relationship between beliefs, attitude and behaviour and identifies the sequential channels through which a narrative might be useful in changing behaviour. We test its predictions through an online survey experiment, where we deliver UK natives a favourable narrative about migrants. Treated subjects revise their beliefs about migrants and exhibit significantly more positive self-reported attitudes and more pro-migrant behaviour. Moreover, they update beliefs in a way that gives support to the existence of confirmation bias. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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16. Performance of styrene polymerized plastic scintillator with micropixel avalanche photodiode.
- Author
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Sadigov, A., Ahmadov, F., Ahmadov, G., Aksu, E., Berikov, D., Nuruyev, S., Akbarov, R., Holik, M., Mamedov, F., Nagiyev, J., Güner, S. Gürbüz, Mammadli, A., Suleymanova, N., Abbasova, C., Melikova, S., Yilmaz, E., Tagiyev, O., Lyubchyk, S., and Sadygov, Z.
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SCINTILLATORS , *NEUTRON counters , *GAMMA rays , *BETA rays , *FORM perception , *PLASTIC marine debris - Abstract
This paper presents the performance of polystrene based plastic scintillator produced in Turkish Energy, Nuclear and Mineral Research Agency (TENMAK). The scintillator is manufactured using thermal polymerization of commercially available styrene monomer doped with first and second fluorescent dyes. The absorption spectrum of the scintillator exhibited two absorption bands at 225 nm and 340 nm, with an absorption edge observed at 410 nm. The wavelength of the emitted light was measured in the range of 400–800 nm, with a maximum intensity at 427 nm. Internal conversion electrons from the 137Cs source were used to evaluate the characteristics of the new scintillator, particularly its light yield. As the light readout the MAPD-3NM type silicon photomultiplier array (4 × 4) with an active area of 15 × 15 mm 2 , assembled using single MAPDs with an active area of 3.7 × 3.7 mm 2 , was used. The light yield of the scintillator was determined to be 6134 photons/MeV. In addition, the efficiency of the scintillator for gamma rays with an energy of 662 keV was found out to be approximately 1.8%. CmBe neutron source was employed to evaluate its fast neutron detection performance. However, neutron/gamma discrimination using pulse shape discrimination (charge integration) method was not observed. The results demonstrate the potential of produced plastic scintillator for various applications, particularly in radiation monitoring and detection systems. • The scintillator is manufactured using thermal polymerization of commercially available styrene monomer doped with first and second fluorescent dyes. • Plastic scintillator exhibits two absorption bands at 225 and 340 nm, with an absorption edge observed at 410 nm. • The efficiency of the scintillator for gamma rays with an energy of 662 keV was found out to be approximately 1.8%. • The plastic scintillator coupled to micropixel avalanche photodiode demonstrated effective detection of beta particles emitted by 137Cs and 90Sr sources, with an energy resolution of 25% for monoenergetic (626 keV) electrons. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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17. Day-to-day dynamics with advanced traveler information.
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Ye, Hongbo, Xiao, Feng, and Yang, Hai
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FORM perception , *ROUTE choice , *TRAVELERS , *INFORMATION storage & retrieval systems - Abstract
• The day-to-day dynamics considering travel time information from the Advanced Traveler Information System (ATIS) and user learning are investigated. • The day-to-day dynamics are modeled using both discrete-time and continuous-time models. • The respective stability conditions regarding the system parameters for both discrete-time and continuous-time models are provided. • It is found that changing ATIS's publishing information from historical information to predicted information will change the system stability. This paper studies how the advanced traveler information affects the stability of the day-to-day flow evolution of a transportation system. Two scenarios are investigated regarding the types of information provided, where one type is the historical travel time and the other the forecasted travel time. Given the information, travelers are assumed to form their own perception/prediction on travel time and further choose the routes. The day-to-day dynamics under the two above-mentioned scenarios are formulated using both discrete-time and continuous-time models, and their respective local stability is analyzed. Findings from the discrete-time and continuous-time models are compared, which show that: (i) the discrete-time models behave in a more complex fashion than the continuous-time models, and (ii) the conclusions drawn from the discrete-time modeling and continuous-time modeling can be consistent, different or contradictory, which depends on the system parameters, network structure, the travel time functions and the route choice probability functions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
18. Interactive directional ambient occlusion and shadow computations for volume ray casting.
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Campagnolo, Leonardo Q. and Celes, Waldemar
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DEPTH perception , *SHADES & shadows , *FORM perception , *GAUSSIAN function - Abstract
• Method to compute directional ambient occlusion and shadows for volume ray casting. • Realistic volume rendering at interactive framerate based on cone tracing. • Transparency computation based on Gaussian integrals at samples along cone axis. • Directional ambient occlusion and shadows under the same framework. Volume rendering is a widely used technique to visualize 3D scalar data. To enhance visual shape and depth perception, distinct illumination techniques have been proposed, adding different types of lighting effects. In this paper, we explore a new strategy to compute directional ambient occlusion and shadows for volume ray casting to render structured datasets. Our algorithm computes occlusion of traced cones by evaluating Gaussian integrals at discrete samples along the cone axis. The computed occlusion is then used to add directional ambient occlusion effects and to generate shadows. Given the extinction coefficient data volume, we create one extra volume computing representative amplitudes of Gaussian functions. Mipmapping is then used to effectively evaluate Gaussian integrals with different sizes placed along the cone axis, adapting a circle packing approach. We demonstrate that the proposed method delivers a better balance between quality results and performance when compared to previous specialized procedures, with the advantage of combining directional ambient occlusion and shadow generation under the same framework. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
19. Characterization of large diameter dual-mode cerium-doped Tl2LiYCl6 advanced scintillator.
- Author
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Hawrami, R., Ariesanti, E., Burger, A., Neely, E., Glodo, J., Pandian, L., Ji, C., Stepanoff, S., Wolfe, D.E., and Liang, F.
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FORM perception , *SCINTILLATORS , *NEUTRON counters , *SCINTILLATION counters , *DIAMETER , *BOWLING games - Abstract
In this paper we are reporting on the progress and scale up of the Cerium-doped Tl 2 LiYCl 6 (TLYC) scintillator. The boules up to 2-inch in diameter were grown by the Bridgman method at Fisk University. The lapped and polished samples were characterized for their scintillation properties including gamma-neutron dual mode detection. The 1.5-inch diameter samples demonstrated the energy resolution as good as 4.5% (FWHM) at 662 keV. The neutron peak due to 6Li(n, α) reaction was observed at 1.8 MeV gamma equivalent energy. Gamma-neutron pulse shape discrimination (PSD) was demonstrated with the Figure-of-Merit (FOM) of 1.8. The hermetically encapsulated samples were also evaluated for their radiation hardness with irradiation up to 1 Mrad. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
20. Influence of sampling properties of fast-waveform digitizers on neutron−gamma-ray, pulse-shape discrimination for organic scintillation detectors.
- Author
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Flaska, Marek, Faisal, Muhammad, Wentzloff, David D., and Pozzi, Sara A.
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ORGANIC scintillators , *WAVE analysis , *NEUTRONS , *GAMMA rays , *FORM perception , *SIGNAL sampling - Abstract
Abstract: One of the most important questions to be answered with regard to digital pulse-shape discrimination (PSD) systems based on organic scintillators is: What sampling properties are required for a fast-waveform digitizer used for digitizing neutron/gamma-ray pulses, while an accurate PSD is desired? Answering this question is the main objective of this paper. Specifically, the paper describes the influence of the resolution and sampling frequency of a waveform digitizer on the PSD performance of organic scintillators. The results presented in this paper are meant to help the reader choosing a waveform digitizer with appropriate bit resolution and sampling frequency. The results presented here show that a 12-bit, 250-MHz digitizer is a good choice for applications that require good PSD performance. However, when more accurate PSD performance is the main requirement, this paper presents PSD figures of merit to qualify the impact of further increasing either sampling frequency or resolution of the digitizer. [Copyright &y& Elsevier]
- Published
- 2013
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21. The impact of expectation discrepancy on food consumers' quality perception and purchase intentions: Exploring mediating and moderating influences in China.
- Author
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Liu, Zhao-ge, Li, Xiang-yang, Wu, Chong, Zhang, Rui-jin, and Durrani, Dilawar Khan
- Subjects
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SEMI-structured interviews , *EXPECTATION (Psychology) , *FORM perception , *INTENTION - Abstract
The discrepancy between expected and actual food product features can be an important indicator of food quality and thus may inform consumer decisions. Using mixed method design, this paper explores whether and how expectation discrepancy affects food consumers' quality perception and purchase intentions under food safety risk situation. In the first phase, a qualitative study based on in-depth semi structured interviews (N = 15) was conducted. The interview results revealed that consumers in general responded negatively towards the existence of expectation discrepancies as it led to poor perceived food quality. It was further revealed that the discrepancy in expectation dimensions had a stronger effect on consumers' perceptions as compared to the discrepancy in expectation extent. In the second phase extensive online survey (N = 2172), it was confirmed that expectation discrepancy had significantly affected quality perceptions and purchase intentions. Moreover, perceived quality played a mediating role between expectation discrepancy and purchase intentions. In addition, expectation proportion (measured with the importance of specific food feature) was shown to strengthen (moderate) the impact of expectation discrepancy. Furthermore, the effects of expectation discrepancy were stronger for high-risk food (versus low risk food). The current paper shows that the effects of expectation discrepancy play a highly significant role in forming perceptions about food safety, therefore, precise marketing strategies can be made by clustering consumers according to the expectation proportions. • Consumers had a negative attitude towards the existence of expectation discrepancies. • The negative quality perception limited consumers' purchase intentions. • Expectation dimension discrepancy had a stronger influence than extent discrepancy. • Effects of expectation discrepancy were higher for high-risk food. • Expectation proportions strengthened the impact of expectation discrepancy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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22. Pulse shape discrimination of CLYC scintillator coupled with a large SiPM array.
- Author
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Dinar, N., Celeste, D., Silari, M., Varoli, V., and Fazzi, A.
- Subjects
- *
FORM perception , *SCINTILLATORS , *NEUTRONS , *PROBLEM solving - Abstract
This paper discusses measurements performed to evaluate the possibility to build a neutron probe based on a CLYC scintillator coupled with a large SiPM array. The use of a large SiPM array allows optimizing the light collection, necessary for spectrometry. However, a large SiPM array leads to huge capacitance, whose main impact is to slow down the input signals. Therefore, pulse shape discrimination (PSD) is lost due to the electronic process. To solve this problem, an electronic board was designed to extract the fastest scintillation decay times from the crystal without cutting the crystal response. The impact of using a large SiPM array instead of a PMT is evaluated by comparing the PSDs and the scintillation decay times. A figure of merit (FOM) of 2.3 was found with the SiPM versus a value of 2.64 for the PMT. In addition, the neutron efficiency was measured and compared to the one simulated with the MCNP code. The angular dependence and the linearity range in dose rate were also evaluated. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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23. Application of deconvolution to recover frequency-domain multiplexed detector pulses.
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Mishra, M., Mattingly, J., and Kolbas, R.M.
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- *
DECONVOLUTION (Mathematics) , *NUCLEAR counters , *DETECTORS , *FORM perception , *FREQUENCIES of oscillating systems , *BIOELECTROCHEMISTRY , *SCINTILLATORS - Abstract
Multiplexing of radiation detectors reduces the number of readout channels, which in turn reduces the number of digitizer input channels for data acquisition. We recently demonstrated frequency domain multiplexing (FDM) of pulse mode radiation detectors using a resonator that converts the detector signal into a damped sinusoid by convolution. The detectors were given unique "tags" by the oscillation frequency of each resonator. The charge collected and the time-of-arrival of the detector pulse were estimated from the corresponding resonator output in the frequency domain. In this paper, we demonstrate a new method to recover the detector pulse from the damped sinusoidal output by deconvolution. Deconvolution converts the frequency-encoded detector signal back to the original detector pulse. We have developed a new prototype FDM system to multiplex organic scintillators based on convolution and deconvolution. Using the new prototype, the charge collected under the anode pulse can be estimated from the recovered pulse with an uncertainty of about 4.4 keVee (keV electron equivalent). The time-of-arrival can be estimated from the recovered pulse with an uncertainty of about 102 ps. We also used a CeBr 3 inorganic scintillator to measure the Cs-137 gamma spectrum using the recovered pulses and found a standard deviation of 13.8 keV at 662 keV compared to a standard deviation of 13.5 keV when the original pulses were used. Coincidence measurements with Na-22 using the deconvolved pulses resulted in a timing uncertainty of 617 ps compared to an uncertainty of 603 ps using the original pulses. Pulse shape discrimination was also performed using Cf-252 source and EJ-309 organic scintillator pulses recovered by deconvolution. A figure of merit value of 1.08 was observed when the recovered pulses were used compared to 1.2 for the original pulses. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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24. Still holding after all these years: An action-perception dissociation in patient DF.
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Ganel, Tzvi and Goodale, Melvyn A.
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- *
VISUOMOTOR coordination , *FORM perception , *BRAIN damage , *DIRECT action - Abstract
Patient DF, who has bilateral damage in the ventral visual stream, is perhaps the best known individual with visual form agnosia in the world, and has been the focus of scores of research papers over the past twenty-five years. The remarkable dissociation she exhibits between a profound deficit in perceptual report and a preserved ability to generate relatively normal visuomotor behaviour was early on a cornerstone in Goodale and Milner's (1992) two visual systems hypothesis. In recent years, however, there has been a greater emphasis on the damage that is evident in the posterior regions of her parietal cortex in both hemispheres. Deficits in several aspects of visuomotor control in the visual periphery have been demonstrated, leading some researchers to conclude that the double dissociation between vision-for-perception and vision-for-action in DF and patients with classic optic ataxia can no longer be assumed to be strong evidence for the division of labour between the dorsal and ventral streams of visual processing. In this short review, we argue that this is not the case. Indeed, after evaluating DF's performance and the location of her brain lesions, a clear picture of a double dissociation between DF and patients with optic ataxia is revealed. More than quarter of a century after the initial presentation of DF's unique case, she continues to provide compelling evidence for the idea that the ventral stream is critical for the perception of the shape and orientation of objects but not the visual control of skilled actions directed at those objects. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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25. Perceptions, people and place: Findings from a rapid review of qualitative research on youth gambling.
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Wardle, Heather
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- *
SCIENTIFIC literature , *LITERATURE reviews , *YOUTH , *QUALITATIVE research , *FORM perception - Abstract
Exploring perceptions, experiences and determinants of youth gambling is crucial for understanding both the impact of youth gambling now and the antecedents of future behaviour. Qualitative research plays an important role in exploring these processes, yet to date, there has been no systematic review of qualitative scientific literature of youth gambling behaviour. A rapid review of three databases (PubMed, Scopus, Web of Science) and grey literature was conducted to map what qualitative research has been conducted, to identify gaps and discern emerging theories or themes about youth gambling behaviour. Peer-reviewed studies were included if they qualitatively explored youth experiences or perceptions of gambling. Narrative and thematic synthesis identified key descriptive and analytical themes covered by the studies. From 75 studies, 21 papers were included. Studies focused on youth perceptions of gambling (including advertising) and/or the factors shaping behaviour. Those which examined perceptions highlighted the normalcy of gambling in the minds of youth and its embeddedness in everyday life but also ambiguity and nuance around their differing perceptions of what gambling is. Studies emphasised the relationship between people (family, peers), place, technology and advertising as key facilitators of behaviour. This review shows young people's perceptions of gambling differs from legal and legislative definitions, which risks underestimating the nature and extent of youth gambling behaviour. There are also notable gaps in knowledge, specifically around the role of technology in shaping gambling behaviours beyond consideration of access and availability. There is a pressing need to better understand the whole techno-ecosystem in which gambling is situated and young people's relationship with it to understand youth gambling. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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26. Multi-channel integrated circuits for the detection and measurement of ionizing radiation
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Engel, G.L., Duggireddi, N., Vangapally, V., Elson, J.M., Sobotka, L.G., and Charity, R.J.
- Subjects
- *
INTEGRATED circuits , *IONIZING radiation measurement , *SILICON diodes , *SIGNAL processing , *FORM perception , *HEAVY ions , *NUCLEAR physics - Abstract
Abstract: The Integrated Circuits (IC) Design Research Laboratory at Southern Illinois University Edwardsville (SIUE) has collaborated with the Nuclear Reactions Group at Washington University (WU) to develop a family of multi-channel integrated circuits. To date, the collaboration has successfully produced two micro-chips. The first was an analog shaped and peak sensing chip with on-board constant-fraction discriminators and sparsified readout. This chip is known as Heavy-Ion Nuclear Physics–16 Channel (HINP16C). The second chip, christened PSD8C, was designed to logically complement (in terms of detector types) the HINP16C chip. Pulse Shape Discrimination–8 Channel (PSD8C), featuring three settable charge integration windows per channel, performs pulse shape discrimination (PSD). This paper summarizes the design, capabilities, and features of the HINP16C and PSD8C ICs. It proceeds to discuss the modifications, made to the ICs and their associated systems, which have attempted to improve ease of use, increase performance, and extend capabilities. The paper concludes with a brief discussion of what may be the next chip (employing a multi-sampling scheme) to be added to our CMOS ASIC “tool box” for radiation detection instrumentation. [Copyright &y& Elsevier]
- Published
- 2011
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27. Comparison of detectors with pulse shape discrimination capability for simultaneous detection of gamma-rays, slow and fast neutrons.
- Author
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Grodzicka- Kobylka, M., Szczesniak, T., Swiderski, L., Brylew, K., Moszyński, M., Valiente-Dobón, J.J., Schotanus, P., Grodzicki, K., Mazerewicz, P., Szymanowski, J., and Mianowska, Z.
- Subjects
- *
FAST neutrons , *FORM perception , *LIQUID scintillators , *DETECTORS , *NEUTRON counters , *NEUTRON measurement , *GAMMA rays , *THERMAL neutrons - Abstract
In this paper, five detectors (EJ-270 — single plastic scintillator, EJ-309B5 — single liquid scintillator, and 3 phoswich detectors: EJ-276+GS20, GS20+EJ-276, EJ-309+GS20) were studied in terms of simultaneous detection of gamma-rays and slow and fast neutrons. The measurements were carried out in a mixed field of neutron and gamma radiation from an intense (∼ 106 neutrons/s/4 π) PuBe source. The PuBe neutron source was placed in an 18 cm diameter paraffin ball in order to increase the number of slow neutron detections. This paper covers the measurements of the neutron/gamma discrimination, photoelectron yield and analysis of the light pulse shapes originating from events related to gamma-rays, slow neutrons and fast neutrons. Sensitivity to slow neutrons is also briefly discussed. A comparison of n/ γ discrimination for all of the tested detectors shows excellent performance of all phoswich detectors. Phoswich configurations tested within the scope of this study allow unambiguously resolve all three types of radiation and show superior performance in comparison with single loaded plastic or liquid scintillators. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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28. Enhancement of multimodal biometric segregation using unconstrained cohort normalisation
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Alsaade, F., Ariyaeeinia, A.M., Malegaonkar, A.S., Pawlewski, M., and Pillay, S.G.
- Subjects
- *
PATTERN perception , *FORM perception , *PATTERN recognition systems , *BIOMETRY - Abstract
Abstract: This paper presents an investigation into the effects, on the accuracy of multimodal biometrics, of introducing unconstrained cohort normalisation (UCN) into the score-level fusion process. Whilst score normalisation has been widely used in voice biometrics, its effectiveness in other biometrics has not been previously investigated. This study aims to explore the potential usefulness of the said score normalisation technique in face biometrics and to investigate its effectiveness for enhancing the accuracy of multimodal biometrics. The experimental investigations involve the two recognition modes of verification and open-set identification, in clean mixed-quality and degraded data conditions. Based on the experimental results, it is demonstrated that the capabilities provided by UCN can significantly improve the accuracy of fused biometrics. The paper presents the motivation for, and the potential advantages of, the proposed approach and details the experimental study. [Copyright &y& Elsevier]
- Published
- 2008
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29. Minutiae feature analysis for infrared hand vein pattern biometrics
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Wang, Lingyu, Leedham, Graham, and Siu-Yeung Cho, David
- Subjects
- *
BIOMETRY , *PATTERN perception , *FACIAL expression , *FORM perception , *PATTERN recognition systems - Abstract
Abstract: This paper proposes a novel technique to analyze the infrared vein patterns in the back of the hand for biometric purposes. The technique utilizes the minutiae features extracted from the vein patterns for recognition, which include bifurcation points and ending points. Similar to fingerprints, these feature points are used as a geometric representation of the shape of vein patterns. Analysis of a database of infrared vein patterns shows a trend that for each hand vein pattern image, there are, on average, 13 minutiae points in each vein pattern image, including 7 bifurcation and 6 ending points. The modified Hausdorff distance algorithm is proposed to evaluate the discriminating power of these minutiae for person verification purposes. Experimental results show the algorithm reaches of equal error rate (EER) on the database of 47 distinct subjects, which indicates the minutiae features of the vein pattern can be used to perform personal verification tasks. The paper also presents the preprocessing techniques to obtain the minutiae points as well as in-depth study on their tolerance to processing errors, such as loss of features and geometrical displacement. [Copyright &y& Elsevier]
- Published
- 2008
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30. A cluster validity index for fuzzy clustering
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Wu, Kuo-Lung and Yang, Miin-Shen
- Subjects
- *
PATTERN perception , *ALGORITHMS , *OPTICAL pattern recognition , *FORM perception - Abstract
Abstract: Cluster validity indexes have been used to evaluate the fitness of partitions produced by clustering algorithms. This paper presents a new validity index for fuzzy clustering called a partition coefficient and exponential separation (PCAES) index. It uses the factors from a normalized partition coefficient and an exponential separation measure for each cluster and then pools these two factors to create the PCAES validity index. Considerations involving the compactness and separation measures for each cluster provide different cluster validity merits. In this paper, we also discuss the problem that the validity indexes face in a noisy environment. The efficiency of the proposed PCAES index is compared with several popular validity indexes. More information about these indexes is acquired in series of numerical comparisons and also three real data sets of Iris, Glass and Vowel. The results of comparative study show that the proposed PCAES index has high ability in producing a good cluster number estimate and in addition, it provides a new point of view for cluster validity in a noisy environment. [Copyright &y& Elsevier]
- Published
- 2005
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31. Discrimination of piled-up neutron-gamma pulses using charge comparison method and neural network for CLYC detectors.
- Author
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Yi, Chuqi, Han, Jifeng, Song, Ruiqiang, Yan, Xiaoyu, Ren, Feixu, Luo, Xiaobing, Han, Zheng, Wen, Chun, Qu, Guofeng, Liu, Xingquan, Lin, Weiping, Wang, Peng, Fan, Yixiang, Qian, Sen, Wang, Zhigang, Tang, Gao, Qin, Laishun, Wang, Xu, and Liu, Jizhen
- Subjects
- *
CONVOLUTIONAL neural networks , *COINCIDENCE , *ARTIFICIAL neural networks , *FORM perception , *DETECTORS - Abstract
To realize neutron-gamma discrimination of piled-up pulses in high counting rate circumstances, the discrimination performance of the charge comparison method and three neural network models to actual piled-up pulses was studied in this paper. The neural network models, including a residual neural network (ResNet), a convolutional neural network (CNN) and a fully connected neural network (FCNN), were trained and tested by seven kinds of actual experimental data sets, which included the background signals (bg), non-piled-up neutron (n) and gamma (g) pulses as well as piled-up neutron + neutron (n + n), neutron + gamma (n + g), gamma + neutron (g + n), and gamma + gamma (g + g) pulses. The labels of the seven data sets were provided after discriminating by the charge comparison method. The results showed that the charge comparison method could be applied to discriminate piled-up neutron-gamma pulses with the Figure of Merit (FoM) value of 1.0. The integration length has been optimized to be different for piled-up and non-piled-up pulses, but follow the same criterion for neutron and gamma discrimination. The FoM values are worse than that of non-piled-up signals because the baseline fluctuation is very large under high counting rate conditions, which gives lots of interference to pulse shape discrimination. The ResNet model has the highest total prediction accuracy (93.85%) for the seven signal types, and through the comparison and analysis of the inconsistent events discriminated by the charge comparison method and the ResNet model, it is concluded that the discrimination result of the ResNet model is more accurate. These results indicate that both the charge comparison method and residual neural network can be used for complicated n/ γ discrimination under high counting rate conditions, and the residual neural network works better. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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32. 6Li-loaded liquid scintillators produced by direct dissolution of compounds in diisopropylnaphthalene (DIPN).
- Author
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Zaitseva, N.P., Carman, M.L., Ford, M.J., Glenn, A.M., Roca, Ch., Durham, S., Sutanto, F., Dazeley, S.A., and Bowden, N.S.
- Subjects
- *
LIQUID scintillators , *SCINTILLATORS , *FORM perception , *NEUTRON counters , *ATOMIC weights , *HYDROCHLORIC acid - Abstract
The paper describes preparation of 6Li-loaded liquid scintillators by methods involving direct dissolution of 6Li salts in the commercial diisopropylnaphthalene (DIPN) solvent, without the formation of water-in-oil emulsions. Methods include incorporation of 6Li that, unlike previously reported formulations, does not require additions of water or a strong acid such as hydrochloric acid (HCl). Results of the conducted experiments show that dissolution of aromatic and aliphatic 6Li salts in DIPN can be easily achieved at 0.1%–0.3% by weight of atomic 6Li, using small additions of waterless surfactants, or mild carboxylic acids. An alternative way suggests incorporation of 6Li as a part of a surfactant molecule that can be dissolved in DIPN without any solubilizing additions. Proposed methods enable preparation of efficient 6Li-loaded liquid scintillators that, at a large scale of 50 cm, exhibit good pulse shape discrimination (PSD) properties combined with up to 107% of light output and up to 115% of the attenuation length measured relative to standard undoped EJ-309 liquid scintillator. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Towards next generation virtual power plant: Technology review and frameworks.
- Author
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Bhuiyan, Erphan A., Hossain, Md. Zahid, Muyeen, S.M., Fahim, Shahriar Rahman, Sarker, Subrata K., and Das, Sajal K.
- Subjects
- *
FRAMES (Social sciences) , *POWER plants , *FORM perception , *ENERGY management , *ENERGY industries - Abstract
Modernization in the area of smart energy equipment, are forming the perception of an interlinked energy network in subsequent times. This energy network is contemplated to govern real-time energy consumption and optimization in the future. Traversing a prolonged period of development, the energy industry has reached the landmark of Virtual Power Plant (VPP) and still going onward to this newfangled energy network, also can be called the next generation VPP. This paper demonstrates the challenges and opportunities in executing the transpiring aspects of the next generation VPP. Based on essential components and requisites, detailed descriptions are depicted from different technological viewpoints such as electrical and communication, computing technologies, energy management, economic profit, geographical factors, and adoption of emerging technologies. We also present the recent updates of existing VPP projects. Finally, considerations towards implementing the next generation VPP are marked out, along with necessary frameworks, regulations, and policies. This paper can provide prudent support for researchers and practitioners in the field of VPP. [Display omitted] • Review of development aspects in virtual power plants (VPP). • Critical requirements and necessary components for VPPs are presented. • Emerging technologies that can be integrated with next generation VPP are discussed. • Challenges and opportunities in the road of developing the next generation VPP are characterized. • Next generation VPP's framework, policies, and regulations are outlined. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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34. Generalized method for the optimization of pulse shape discrimination parameters.
- Author
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Zhou, J., Abdulaziz, A., Altmann, Y., and Di Fulvio, A.
- Subjects
- *
FORM perception , *FAST neutrons , *SCINTILLATION counters , *NEUTRON measurement , *STRUCTURAL optimization , *SCINTILLATORS - Abstract
Organic scintillators exhibit fast timing, high detection efficiency for fast neutrons and pulse shape discrimination (PSD) capability. PSD is essential in mixed radiation fields, where different types of radiation need to be detected and discriminated. In neutron measurements for nuclear security and non proliferation effective PSD is crucial, because a weak neutron signature needs to be detected in the presence of a strong gamma-ray background. The most commonly used deterministic PSD technique is charge integration (CI). This method requires the optimization of specific parameters to obtain the best gamma-neutron separation. These parameters depend on the scintillating material and light readout device and typically require a lengthy optimization process and a calibration reference measurement with a mixed source. In this paper, we propose a new method based on the scintillation fluorescence physics that enables to find the optimum PSD integration gates using only a gamma-ray emitter. We demonstrate our method using three organic scintillation detectors: deuterated trans-stilbene, small-molecule organic glass, and EJ-309. In all the investigated cases, our method allowed finding the optimum PSD CI parameters without the need of iterative optimization. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Efficient pulse shape discrimination using scalogram image masking and decision tree.
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Abdelhakim, Assem and Elshazly, Ehab
- Subjects
- *
FORM perception , *DECISION trees , *NUCLEAR counters , *GAMMA rays , *WAVELET transforms , *MACHINE learning , *PIXELS - Abstract
In radiation detectors, pulse shape discrimination (PSD) is essential for classifying radiation types. Designing efficient PSD method that has high discrimination accuracy and low time consumption is a challenging task. In this paper, an efficient approach is proposed to discriminate neutron and gamma pulses in radiation detectors, where high classification accuracy and low time consumption are presented. The proposed method is based on image processing through the Scalogram representation of the pulses, which is acquired using the continuous wavelet transform (CWT). From the grayscale Scalogram image, the higher energy density region is segmented, where lower effect of noise is located. Furthermore, a mask image is generated to select a portion from the segmented region, where the difference between the neutron and gamma pulses is significant. The discrimination factor is evaluated according to the number of white pixels in the masked image. Machine learning is utilized to provide a regression model for the designed method, where the discrimination time is significantly reduced. The decision tree regression model is used to predict the value of the discrimination factor according to the principal components of the pulse signal. To validate the effectiveness of the proposed method, a performance comparison is conducted with state-of-the art and traditional PSD techniques using synthetic data. Experimental results show that the proposed method outperforms other PSD methods in terms of the figure of merit and the classification accuracy. Moreover, the proposed method provides less time-consuming discrimination compared to recent methods. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Creating conditions for critical trust – How an uncertainty-based risk perspective relates to dimensions and types of trust.
- Author
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Fjaeran, Lisbet and Aven, Terje
- Subjects
- *
RISK perception , *TRUST , *FORM perception , *FEED additives , *SCIENTIFIC communication - Abstract
• The paper discusses how different risk perspectives relate to types of trust. • The paper highlights the importance of the scepticism dimension of trust. • It provides new insights about the role of the risk assessor in this context. • The analysis is based on the Social Amplification of Risk Framework. • A case related to the use of a feed additive is used to illustrate the discussion. Although some disagreement about the strength of the relationship, it is generally agreed within risk research, that trust plays a central role in shaping risk perception and risk responses. Over recent decades, risk managing institutions have experienced what by many has been described as a decline in public trust. Strategies like stakeholder involvement and communication of scientific uncertainties are increasingly implemented to rebuild levels of trust but often prove less effective. Also, trust-related research mainly revolves around the relation between regulators and authorities, on one hand, and the public, on the other, with less attention given to the role of the scientific risk assessor. In this paper, we argue that assessors can act to improve conditions of trust by adopting an understanding of risk, stressing uncertainty and knowledge aspects when conceptualizing and characterizing risk. While 'full' trust commonly is seen as an ideal situation and distrust as a state of affairs to be prevented, this approach involves recognizing distrust as a resource. Based on an example regarding the authorization and regulation of a feed additive and the Social Amplification of Risk Framework, we show how such a perspective affects trust, both as a filter for processing, interpreting and responding to risk-related information and as an impact following such processes. Drawing on a typology of trust, we also illustrate how this relates to different dimensions and forms of trust. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
37. Assessing and minimizing contamination in time of flight basedvalidation data.
- Author
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Lennox, Kristin P., Rosenfield, Paul, Blair, Brenton, Kaplan, Alan, Ruz, Jaime, Glenn, Andrew, and Wurtz, Ronald
- Subjects
- *
FORM perception , *POISSON regression , *TIME-of-flight mass spectrometry , *GAMMA rays , *NEUTRONS - Abstract
Time of flight experiments are the gold standard method for generating labeled training and testing data for the neutron/gamma pulse shape discrimination problem. As the popularity of supervised classification methods increases in this field, there will also be increasing reliance on time of flight data for algorithm development and evaluation. However, time of flight experiments are subject to various sources of contamination that lead to neutron and gamma pulses being mislabeled. Such labeling errors have a detrimental effect on classification algorithm training and testing, and should therefore be minimized. This paper presents a method for identifying minimally contaminated data sets from time of flight experiments and estimating the residual contamination rate. This method leverages statistical models describing neutron and gamma travel time distributions and is easily implemented using existing statistical software. The method produces a set of optimal intervals that balance the trade-off between interval size and nuisance particle contamination, and its use is demonstrated on a time of flight data set for Cf-252. The particular properties of the optimal intervals for the demonstration data are explored in detail. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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- View/download PDF
38. Cancelling cancellation? Sensorimotor control, agency, and prediction.
- Author
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Press, Clare, Thomas, Emily R., and Yon, Daniel
- Subjects
- *
CONTROL (Psychology) , *FORM perception , *ACTION theory (Psychology) , *AGENCY theory , *FORECASTING - Abstract
For decades, classic theories of action control and action awareness have been built around the idea that the brain predictively 'cancels' expected action outcomes from perception. However, recent research casts doubt over this basic premise. What do these new findings mean for classic accounts of action? Should we now 'cancel' old data, theories and approaches generated under this idea? In this paper, we argue 'No'. While doubts about predictive cancellation may urge us to fundamentally rethink how predictions shape perception, the wider pyramid using these ideas to explain action control and agentic experiences can remain largely intact. Some adaptive functions assigned to predictive cancellation can be achieved through quasi-predictive processes, that influence perception without actively tracking the probabilistic structure of the environment. Other functions may rely upon truly predictive processes, but not require that these predictions cancel perception. Appreciating the role of these processes may help us to move forward in explaining how agents optimise their interactions with the external world, even if predictive cancellation is cancelled from theory. • Can theories of action and agency survive if we cancel the idea of cancellation? • Here, we consider how they can incorporate new evidence challenging the classic view. • Some crucial processes influence perception without tracking probabilities. • Predictive functions may be necessary but not cancel perception. • Understanding the specific role of these processes is crucial for explaining action. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Delayed radioluminescence of some heterostructured organic scintillators.
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Galunov, Nikolai, Gryn, Dmytro, Karavaeva, Nataliya, Khromiuk, Ilarion, Lazarev, Igor, Navozenko, Oleksandr, Naumenko, Antonina, Tarasenko, Oleg, and Yashchuk, Valeriy
- Subjects
- *
RADIOLUMINESCENCE , *SCINTILLATORS , *DELAYED fluorescence , *PHOSPHORESCENCE , *FORM perception , *INHOMOGENEOUS materials , *SINGLE crystals - Abstract
The processes leading to the appearance of phosphorescence and delayed fluorescence in organic molecular materials compete. This paper compares the ratio of the intensities of delayed fluorescence and phosphorescence with the pulse shape discrimination (PSD) capability of organic scintillators. The paper considers hot-pressed polycrystals and composite samples containing single-crystal organic grains as the heterostructured organic scintillators. The single crystals and heterostructured scintillators contained trans -stilbene, p -terphenyl, anthracene, and phenanthrene. Samples based on trans -stilbene and p -terphenyl at 77 K showed an intense delayed fluorescence, which appeared against the background of weak phosphorescence. It indicates the active formation of delayed fluorescence in these materials. We did not observe a similar effect for samples based on anthracene and phenanthrene. At the same time, it was the samples containing trans -stilbene and p -terphenyl grains that showed the best PSD capability at room temperature. Single-crystal and heterostructured materials containing the same scintillation substance demonstrate a close PSD capability. A comparative analysis of the intensities of delayed fluorescence and phosphorescence at low temperatures can be a method of searching for new materials that are promising for PSD problems. • Organic polycrystalline and composite scintillators are studied. • The proportion between the delayed and prompt radioluminescence is analysed. • The intensities of phosphorescence and delayed fluorescence at 77 K are compared. • PSD capability of heterogeneous materials and single crystals is close to each other. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
40. French attitudes on climate change, carbon taxation and other climate policies.
- Author
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Douenne, Thomas and Fabre, Adrien
- Subjects
- *
CARBON taxes , *CLIMATE change , *CLIMATOLOGY , *ATTITUDE change (Psychology) , *FORM perception - Abstract
• French people have limited knowledge about climate change but worry about it. • They prefer green investments or regulations to a tax and dividend. • Distributive effects and lack of alternatives prevent carbon tax acceptance. • Improving knowledge is predicted to increase ecological attitudes and concern. • Unlike in the US, partisanship does not interact with education to shape perceptions. This paper aims to assess the prospects for French climate policies after the Yellow Vests crisis halted the planned increase in the carbon tax. From a large representative survey, we elicit knowledge, perceptions and values over climate change, we examine opinions relative to carbon taxation, and we assess support for other climate policies. Specific attention is given to the link between perceptions of climate change and attitudes towards policies. The paper also studies in detail the determinants of attitudes in terms of political and socio-demographic variables. Among many results, we find limited knowledge but high concern for climate change. We also document a large rejection of the carbon tax but majority support for stricter norms and green investments, and reveal the rationales behind these preferences. Our study entails policy recommendations, such as an information campaign on climate change. Indeed, we find that climate awareness increases support for climate policies but no evidence for the formation of opinions through partisan cues as in the US, suggesting that better access to science could foster support for climate policies. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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41. Investigating the minimum perceived linewidth of electroadhesion devices.
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Sun, Zuowei, Sun, Xiaoying, and Li, Kaiwei
- Subjects
- *
FORM perception , *SENSOR placement , *POSITION sensors , *TRAFFIC safety , *LOW voltage systems - Abstract
Electroadhesion devices render shape perception on the flat surface by reconstructing friction based on the finger position. The positioning sensor with a low sampling rate limits rendering because of the discontinuous friction caused by fast finger sliding. The positioning sensor with a higher sampling rate needs to be designed to meet the high-fidelity rendering at fast movement. However, a sensor with a high sampling rate that exceeds the range of human perception is also unnecessary because this will increase the burden of the hardware and software. Thus, it is importance to determine the upper limit of the sampling rate required for electroadhesion devices. The minimum perceived width and sliding velocity together determine the maximum sampling rate. This paper uses the line with varying widths to study the minimum perceived linewidth. The minimum perceived linewidths and influencing factors were studied by psychophysical experiments under 16 conditions of four driving voltages and four sliding velocities. The results showed that minimum perceived linewidths were in the micron scale, and the averages were 5.00–53.75 μ m. The minimum perceived linewidths were significantly affected by voltages and velocities, especially at low voltages and fast velocities. The minimum perceived width and influencing factors guide the future electroadhesion application. • We proposed a design to maintain finger moving velocity constant and obtain 10 μ m smallest linewidth with four different velocities. • We measured minimum perceived linewidths by electroadhesion for the first time and determined dual effects of driving voltage and moving velocity. • We found that the averages of minimum perceived linewidths increased with increasing velocities at low voltages. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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42. Unpacking planners' views of the success and failure of planning in post-apartheid South Africa.
- Author
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Denoon-Stevens, Stuart Paul, Andres, Lauren, Nel, Verna, and Jones, Phil
- Subjects
- *
POST-apartheid era , *FORM perception , *PLANNERS , *BUILT environment , *PRODUCTION planning - Abstract
This paper discusses post-apartheid planning reform in South Africa and identifies the successes and failures thereof, as understood by South African planners. We noted a perception of success regarding the reform of planning legislation; however, the general feeling was that planning had failed to achieve spatial transformation in the post-apartheid era. A variety of reasons were given for this: the failure to achieve reservation of planning work for planners, political interference, weak planning tools, lack of capacity, and planners' lack of key skills. We argue that underlying these failures was a deeper issue, namely that many powerful stakeholders in the built environment seemingly did not ascribe value to the planning process. In other instances, they may accept the value of the process, but not the uniqueness of planners' skills. This divergence of opinion of and power struggle between the legitimacy of planning versus planners shapes both the form that planning reform takes, but also the perceptions of the successes or failures of planning reform. Consequentially, this means that to achieve 'successful' planning reform, it is necessary to account for how the interaction of micro (individual) and macro-meso (organisational, societal) agendas shape these processes. • South African planners perceived planning reform post-apartheid as failed. • The perception of failure related to lack of control over planning by planners. • Individual agendas of planners affected perception and form of planning reforms. • Planners are thus both enablers and limiters of planning reform. • Reform of planning systems needs to be both technical and tactical. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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43. Incremental Similarity for real-time on-line incremental learning systems.
- Author
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Režnáková, Marta, Tencer, Lukas, and Cheriet, Mohamed
- Subjects
- *
INSTRUCTIONAL systems , *PATTERN perception , *FORM perception , *DATABASES , *COMPREHENSION - Abstract
The expectation of higher accuracy in recognition systems brings the problem of higher complexity. In this paper we introduce a novel Incremental Similarity (IS) that maintains high accuracy while preserving low complexity. We apply IS to on-line and incremental learning tasks, where the need of low complexity is of significant need. Using IS enables the system to directly compute with the samples themselves and update only few parameters in an incremental manner. We empirically prove its efficiency on several evolving models and show that by using IS they achieve competitive results and outperform the baseline models. We also consider the problem of incremental learning used to handle fast growing datasets. We present a very detailed comparison for not only evolving models, but also for the well-known batch models, showing the robustness of our proposal. We perform the evaluation on various classification problems to show the wide application of evolving models and our proposed IS. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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44. Towards generic image classification using tree-based learning: An extensive empirical study.
- Author
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Marée, Raphaël, Geurts, Pierre, and Wehenkel, Louis
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LEARNING , *INSTRUCTIONAL systems , *PATTERN perception , *FORM perception , *PHOTOGRAPHS , *OPTICAL images - Abstract
This paper considers the general problem of image classification without using any prior knowledge about image classes. We study variants of a method based on supervised learning whose common steps are the extraction of random subwindows described by raw pixel intensity values and the use of ensemble of extremely randomized trees to directly classify images or to learn image features. The influence of method parameters and variants is thoroughly evaluated so as to provide baselines and guidelines for future studies. Detailed results are provided on 80 publicly available datasets that depict very diverse types of images (more than 3800 image classes and over 1.5 million images). [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
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45. On the completeness of feature-driven maximally stable extremal regions.
- Author
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Martins, Pedro, Carvalho, Paulo, and Gatta, Carlo
- Subjects
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PATTERN perception , *FORM perception , *VALUES (Ethics) , *AESTHETICS , *VALUE congruence - Abstract
By definition, local image features provide a compact representation of the image in which most of the image information is preserved. This capability offered by local features has been overlooked, despite being relevant in many application scenarios. In this paper, we analyze and discuss the performance of feature-driven Maximally Stable Extremal Regions (MSER) in terms of the coverage of informative image parts (completeness). This type of features results from an MSER extraction on saliency maps in which features related to objects boundaries or even symmetry axes are highlighted. These maps are intended to be suitable domains for MSER detection, allowing this detector to provide a better coverage of informative image parts. Our experimental results, which were based on a large-scale evaluation, show that feature-driven MSER have relatively high completeness values and provide more complete sets than a traditional MSER detection even when sets of similar cardinality are considered. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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46. Studies on fast neutron imaging with a pixelated stilbene scintillator detector.
- Author
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Höflich, Nina and Pooth, Oliver
- Subjects
- *
FAST neutrons , *SCINTILLATORS , *FORM perception , *DETECTORS , *PHOTOMULTIPLIERS , *GAMMA rays - Abstract
For simultaneous imaging with fast neutrons and gammas we have developed a 16-pixel detector that uses the organic scintillator stilbene as active material. Sixteen stilbene cuboids of size 5 × 5 × 25 mm 3 are arranged in a 4 × 4 grid and read out by silicon photomultipliers. The usage of stilbene allows to distinguish neutron and gamma signals via pulse shape discrimination techniques. In this paper, attenuation measurements and first tomographies of objects containing aluminum and PMMA are presented. Fast neutrons and gammas are delivered by an Americium–Beryllium source. The performance of the tomographic reconstructions with neutrons and gammas is evaluated. It is shown that the combination of the two images can improve the material distinction in the reconstructed object. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. Gamma–neutron imaging system utilizing pulse shape discrimination with CLYC.
- Author
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Whitney, Chad M., Soundara-Pandian, Lakshmi, Johnson, Erik B., Vogel, Sam, Vinci, Bob, Squillante, Michael, Glodo, Jarek, and Christian, James F.
- Subjects
- *
GAMMA rays , *NEUTRONS spectra , *CESIUM compounds , *FORM perception , *PARTICLE physics - Abstract
Recently, RMD has investigated the use of CLYC (Cs 2 LiYCl 6 :Ce), a new and emerging scintillation material, in a gamma–neutron coded aperture imaging system based on RMD׳s commercial RadCam TM instrument. CLYC offers efficient thermal neutron detection, fast neutron detection capabilities, excellent pulse shape discrimination (PSD), and gamma-ray energy resolution as good as 4% at 662 keV. PSD improves the isolation of higher energy gammas from thermal neutron interactions (>3 MeV electron equivalent peak), compared to conventional pulse height techniques. The scintillation emission time in CLYC provides the basis for PSD; where neutron interactions result in a slower emission rise and decay components while gamma interactions result in a faster emission components. By creating a population plot based on the ratio of the decay tail compared to the total integral amplitude (PSD ratio), discrimination of gammas, thermal neutrons, and fast neutrons is possible. Previously, we characterized the CLYC-based RadCam system for imaging gammas and neutrons using a layered W-Cd coded aperture mask and employing only pulse height discrimination. In this paper, we present the latest results which investigate gamma-neutron imaging capabilities using PSD. An FPGA system is used to acquire the CLYC–PSPMT last dynode signals, determine a PSD ratio for each event, and compare it to a calibrated PSD cutoff. Each event is assigned either a gamma (low) or neutron (high) flag signal which is then correlated with the imaging information for each event. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
48. Participation in the administration of elections and perceptions of electoral integrity.
- Author
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Partheymüller, Julia, Müller, Wolfgang C., Rabitsch, Armin, Lidauer, Michael, and Grohma, Paul
- Subjects
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ELECTIONS , *INTEGRITY , *ELECTION Day , *PARTICIPATION , *POLITICAL parties , *FORM perception , *EMPLOYEE recruitment - Abstract
In recent years, election administration has become a subject of intensified debates, raising questions of how to organize elections to ensure electoral integrity. One question concerns who should serve as members of polling station boards, administer election day proceedings, and participate in the vote count. Different models co-exist in modern democracies, with some countries – among them Austria – actively involving the political parties in the election administration. Against this background, this paper examines perceptions of electoral integrity among Austrian poll workers and citizens using data from an original survey of poll workers and survey data of the voting population. The results show that poll workers have greater confidence in the election administration than regular voters but are equally or more skeptical regarding other aspects of electoral integrity. Also, their partisan background shapes perceptions of electoral integrity. To conclude, we discuss the benefits and limitations of the 'party model' for poll worker recruitment. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. Study of silicon photomultipliers (SiPM) with organic scintillator for neutron diagnostics of thermonuclear plasma.
- Author
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Dendene, Omar, Afanasiev, Valery Viktorovich, Lushin, Sergey Vladimirovich, Chergui, Ahmed Cherif, Stifutkin, Alexey Anatolyevich, and Boukerdja, Layachi
- Subjects
- *
NEUTRON counters , *THERMONUCLEAR fusion , *PHOTOMULTIPLIERS , *FORM perception , *NUCLEAR fusion , *NEUTRONS - Abstract
• Dynamic range of SIPMS allowing fusion neutron detection by the recoil proton method. • Evaluation of the ability of SIPMS to discriminate neutrons and gamma rays. • Most suitable SIPMS size parameters for the detection of thermonuclear fusion neutrons. The spectrometry of neutrons produced by fusion reactions of plasmatic ions is the most powerful neutron diagnostic tool for monitoring reactor operating power, temperature and concentration of ions. Currently, new generations of silicon photomultipliers (SiPMs) are being used in several light detection fields, including nuclear domain; they have performances similar to conventional photomultipliers tubes (PMTs), while benefiting advantages of solid-state technology such as insensitivity to magnetic and electric fields, excellent temperature stability, robustness, low operating voltage, small size, and low cost. Consequently, they could be a useful device in neutron spectrometer based on recoil proton method for neutron diagnostics of hot plasmas. In this paper, we have demonstrated SiPMs capabilities to be used for fast neutron detection as well as their dynamic range for thermonuclear fusion neutron spectrometry (14 Mev). The responses of SiPMs having different sizes of active areas and microcells manufactured by Ketek and SensL have been studied. Excellent pulse shape discrimination of PuBe source radiations by SiPMs combined with a stilbene crystal has been proven; the figure of merit has reached 3.33. The study has also allowed the determination of the size parameters of SiPMs that are suitable for neutron diagnostics of thermonuclear plasmas. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
50. Fast FPGA algorithm for neutron–gamma discrimination.
- Author
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Ye, Haoqi, Chen, Lian, Xu, Xiaoyu, and Jin, Ge
- Subjects
- *
FORM perception , *SCINTILLATION counters , *ALGORITHMS , *NEUTRON transport theory - Abstract
Various pulse shape discrimination methods have been used to solve the neutron–gamma discrimination problem, but most of them are limited to offline calculations due to the computation burden and FPGA performance. In order to discriminate neutrons and gamma-rays in real-time, a new algorithm based on the traditional pulse shape discrimination methods is proposed in this paper. The new algorithm considers the physical properties of the pulse signal, which significantly reduces the computation and dead time without affecting precision. The algorithm can also work on the FPGA directly. Good performance was demonstrated in an actual experiment using a CLLB scintillation detector. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
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