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In this paper, CoFe2 O4/biomass carbon composts were prepared by one-pot hydrothermal and high- temperature calcination methods. The microscopic morphology, crystal structure and electromagnetic parame¬ters of the material indicate that CoF2 O4can be uniformly dispersed in the carbon base, and the presence of CoFe2 O4 is conducive to the defective polarization of the biomass during the carbonization process, which is ben racial to the enhancement of the wave absorption properties of the material. Effective regulation of the electro¬magnetic parameters of the composite material by adjusting the content of CoFe2 O4 to optimize tots impedance match mg performance. Experimental results show that the minimum reflection loss (reflection loss, RL) value of-48.0 dB and effective absorption bandwidth (effective absorption bandwidth, EAB) of 5.5 GHz were ob. turned at 2.0 mm thickness of Co2 O4O4/C-3.0 composite. [ABSTRACT FROM AUTHOR]

Semi-automatic extraction of roads is greatly needed to accelerate the acquisition and updating of road maps. However, road surfaces are frequently disturbed on very high spatial resolution (VHSR) remotely sensed satellite imagery, which bothers the road trackers using least-squares-based template matching. This paper presents a novel semi-automatic framework for road tracking from VHSR satellite imagery. First, a human operator inputs three seed points. Second, the computer automatically tracks the road by the template matching using Kullback–Leibler divergence as a similarity measure. At the same time, a human operator is retained in the tracking process to supervise the extracted results, to response to the program's prompts. Once the failure or error happens, the human operator will correct the results and restart the automatic tracking. The above procedure is repeated until a whole road is tracked. Four satellite images with different complexities are used to perform experiments. The results show that our proposed road trackers is capable of automatically, accurately and fast extracting the long and high-level roads from the VHSR satellite images. [ABSTRACT FROM AUTHOR]

This study investigates how bicultural switching could influence cognitive performance on Executive Functions tasks among bicultural-bilinguals.Study 1 (n = 233) integrates self-report questionnaire data on cultural and language behaviour with a priming experiment, providing empirical evidence of young adult bilinguals’ ability to shift between multiple cultures.Study 2 (n = 48) explores the effect of cultural switching frequency on young adult bicultural bilinguals’ performance on tests for interference and inhibition control, set-shifting ability, and attention.Study 1: A repeated measures ANOVA was conducted to determine the effect of different primes on participant’s ratings. We ran a two-way mixed ANOVA to ascertain the effect of interlocutors (Grandparents/relatives, Parents, Siblings, Peers/co-workers, Social media) on behaviour (Cultural, Language). Study 2: A one-way ANOVA was conducted on Simon, Flanker, and Wisconsin Card Sort tasks (WCST). Each of the three attention network components was analysed using a 2 (trial-type, within-subjects) × 2 (Switching Group, between-groups) mixed-ANOVA for the Attention Network task.Study 1: Participants who alternate frequently between cultural frames made a clearer distinction between Western primes than those who switched between cultural frames less, suggesting that the frequency of cultural switching could impact cognition. Study 2: Bicultural bilinguals who switched between cultural frames frequently resolved stimulus-response conflict significantly faster in the Flanker task, made fewer mistakes within each sorting block in the WCST, and had a smaller conflict effect compared to infrequent switchers in the Attention Network Task.This study examines the effects of bicultural switching on Executive Functions of highly proficient bicultural bilinguals, highlighting it as a potential confound in bilingual research. Bicultural switching effects on interference and inhibition-control persist even in participants at the developmental peak of their cognitive processing capabilities after controlling for a plethora of socio-linguistic variables. Our research highlights how this understudied aspect of multiculturalism may have broad implications for bilingual research in Executive Functions. [ABSTRACT FROM AUTHOR]

In most Mobile Laser Scanning (MLS) applications, filtering is a necessary step. In this paper, a segmentation-based filtering method is proposed for MLS point cloud, where a segment rather than an individual point is the basic processing unit. In particular, the MLS point clouds in some blocks are clustered into segments by a surface growing algorithm, and then the object segments are detected and removed. A segment-based filtering method is employed to detect the ground segments. The experiment in this paper uses two MLS point cloud datasets to evaluate the proposed method. Experiments indicate that, compared with the classic progressive TIN (Triangulated Irregular Network) densification algorithm, the proposed method is capable of reducing the omission error, the commission error and total error by 3.62%, 7.87% and 5.54% on average, respectively. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) has been implicated in various health concerns. However, a comprehensive understanding of the specific PM 2.5 components affecting depression remains limited. This study conducted a Cox proportional-hazards model to assess the effect of PM 2.5 components on the incidence of depression based on the China Health and Retirement Longitudinal Study (CHARLS). Participants with 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) score of 10 or higher were classified as exhibiting depression. Our findings demonstrated a significant positive correlation between long-term exposure to black carbon (BC), sulfate (SO 4 2−), and organic matter (OM) components of PM 2.5 and the prevalence of depression. Per 1 Interquartile Range (IQR) increment in 3-year average concentrations of BC, OM, and SO 4 2− were associated with the hazard ratio (HR) of 1.54 (95 % confidence intervals (CI): 1.44, 1.64), 1.24 (95% CI : 1.16, 1.34) and 1.25 (95% CI : 1.16, 1.35). Notably, females, younger individuals, those with lower educational levels, urban residents, individuals who were single, widowed, or divorced, and those living in multi-story houses exhibited heightened vulnerability to the adverse effects of PM 2.5 components on depression. Firstly, pollutant data is confined to subjects' fixed addresses, overlooking travel and international residence history. Secondly, the analysis only incorporates five fine particulate components, leaving room for further investigation into the remaining fine particulate components in future studies. This study provides robust evidence supporting the detrimental impact of PM 2.5 components on depression. The identification of specific vulnerable populations contributes to a deeper understanding of the underlying mechanisms involved in the relationship between PM 2.5 components and depression. • This study explore the association between PM 2.5 components and depression. • Black carbon, sulfate, and organic matter have significant impacts on depression. • Females, who living in multi-story house were susceptible to the PM 2.5 components. [ABSTRACT FROM AUTHOR]

Not only does Singapore have a unique ethnic and multilingual makeup, it also boasts unique language policies, especially with regard to the learning of the official languages. Previous studies of Singaporean youths have largely focused on the differences in attitudes and code-switching between linguistic varieties (e.g. Colloquial Singapore English [Singlish] and Standard Singapore English) as well as looking at the specific languages of Singapore's multilingual community. This paper seeks to examine how Chinese–Singaporean youths differ in their perception of the benefits (general, communicative, cognitive and pragmatic) and disadvantages associated with Mandarin–English bilingualism and their Chinese–Singaporean identity. 165 Chinese–English bilingual youths from secondary schools, Polytechnics/Junior Colleges, University undergraduates and young working adults were stratified based their gender, socio-economic status and self-rated language proficiency. Our findings suggest that bilinguals' self-rated proficiency is generally the best indicator of local Chinese youths' attitudes towards Chinese–English bilingualism and identity, regardless of their current occupation, gender or socio-economic status. [ABSTRACT FROM PUBLISHER]

[Display omitted] Three-dimensional (3D) porous molybdenum disulfide nanosheets/carbon nanofibers (MoS 2 /CNF) hybrid aerogels were synthesized by using solvothermal method and following carbonization, where two-dimensional (2D) MoS 2 nanosheets were homogenously in-situ grown on the interconnected CNF skeleton derived from bacterial cellulose, forming a hierarchical porous structure. This unique heterogeneous structure of the MoS 2 /CNF hybrid aerogels were conducive to electromagnetic loss, including conduction, polarization, multi-scatterings, and reflections, thus resulting in a balanced impedance matching and microwave attenuation capacity. It was found that the resulted MoS 2 /CNF hybrid aerogels demonstrate excellent microwave absorbing performance when the only 5.0 wt% fillers were loaded in paraffin. Particularly, MoS 2 /CNF-2–900 hybrid aerogel displayed an effective absorption bandwidth of 5.68 GHz and minimum reflection loss (RL min) value of −36.19 dB at a thickness of 2.0 mm. As the thickness increases to 4.4 mm, the RL min value of MoS 2 /CNF-2–900 hybrid aerogel reaches −48.53 dB. Electromagnetic loss mechanism analysis indicates that such improved microwave attenuation is attributed to proper component, multiple heterogenous interface and hierarchical porous structures. All the results in this work pave the avenue for the development of ultralight microwave absorber with high absorption capacity as well as broad effective absorption bandwidth. [ABSTRACT FROM AUTHOR]

Graphite matrix/copper composites have found significant potential uses in numerous areas. Until now, a high ambient gas pressure has to be applied to overcome the non-wettability between the copper melt and graphite matrix, which has restricted the technological and economic efficiencies, as well as the composite performance. In this paper, we have proposed a pressureless infiltration strategy to realize the preparation of highly conductive graphite matrix/copper composites. A tungsten carbide network is first in situ constructed in the graphite matrix, transforming the capillary force from the resistance mode to the impetus mode. Results show that the contact angle of graphite/copper decreased from 138.5° to 23° due to the constructed tungsten carbide network. The composites exhibit good interfacial bonding, and the electrical conductivity reaches 15.1 × 105 S/m, far higher than the requirement of the industry standard. [ABSTRACT FROM AUTHOR]

The influence of interface temperature on the damage characteristics of C–Cu contacts' interface plays a critical role in the current-carrying friction process which occurs between the contact pairs. In this paper, a method is proposed to adjust the interface temperature via settling an external heat source. The damage morphology and material transfer of C–Cu contacts are focused on when the range of interface temperature varies from the room temperature (25 °C) to 300 °C. Based on the experimental results, it can be found that high interface temperature can inhibit the surficial erosion of carbon materials, which tends to be obvious, especially along with the increment of current. Moreover, both the delamination wear of carbon surface and the copper-to-carbon transfer behavior decrease with the thermal surge of interface. This beneficial effect of interface temperature results in the reduction in friction coefficient by 14.3%, whereas the negative impacts brought from the high interface temperature are the surface cracking and the rapid recovery of wear rate of carbon materials, under high-current condition. [ABSTRACT FROM AUTHOR]

Carbon material, because of its high thermal conductivity, ablation resistance and friction resistance, has been widely used in the field of electrical engineering. When confronted strong thermal shock, the interface structure of carbon material would cause thermal shock damage by the rapid temperature difference. In order to systematically and quantificationally study the thermal shock damage of carbon materials, an experimental system that can provide rapid temperature difference was built. The experimental results showed that undergoing a temperature difference of 485 °C, more micro-cracks and holes arose in the pure carbon material, resulting in an increase of porosity by 26.39%, an increase friction coefficient by 48.65%, and a decrease of compressive strength by 23.96%. It was also found the ultrasonic velocity linearly decreased with the increase of porosity and the decrease of the compressive strength caused by thermal shock, which meant the non-destructive ultrasonic testing can be used to conveniently and accurately quantify the thermal shock damage. This conclusion also applies when testing copper-impregnated carbon material, making it a potential method to be used in the maintenance of pantograph which can effectively avoid in rail transit accidents. [ABSTRACT FROM AUTHOR]

Microwave absorbers with broadband absorption and lightweight features are highly desirable in electromagnetic interference and pollution treatment. Here, porous and hollow CoNi@C (CNC) microspheres derived from metal-organic frameworks (MOFs) are fabricated by a facile solvothermal route and subsequent annealing process. The morphology, structure, microwave absorption properties and their internal relationship are systematically investigated. For the porous and hollow CNC microspheres, the minimum RL can reach −44.8 dB at 10.7 GHz and the ultra-wide effective absorption bandwidth can reach up to 13.3 GHz (4.7–18.0 GHz) within the thickness of 1.6–4.0 mm. The CNC microspheres exhibit superior microwave absorption performance, attributing to the improved impedance matching and attenuation ability. The hollow structure, interfacial polarization, the synergistic effect between CoNi alloy and graphitized carbon simultaneously account for the microwave absorption mechanisms. Therefore, the present work provides the promising options on the design and preparation of lightweight and high-efficient microwave absorber with tunable component and specific morphology. Image 1 •Hollow and Porous CoNi@C microspheres were synthesized from MOFs precursors via one-step calcination technology. •The modulation of composition and morphology contribute to the tunable electromagnetic parameters of CoNi@C microspheres. •CoNi@C microspheres exhibit superior RL values of −44.8 dB and ultrawide bandwidth (RL < −10 dB) of 13.3 GHz. •The component, morphology, structure, microwave absorption properties and their internal relationship are systematically investigated. [ABSTRACT FROM AUTHOR]

Ecological restoration has been risen to a national strategic project for China and become an significant way to realize ecological civilization construction. As an important way to measure the effectiveness of ecological restoration engineering, the corresponding evaluation provides a reliable basis for ecological restoration decision-making and ecosystem management. Based on remote sensing technology with the advantages of short revisit time, large monitoring range, high spatial resolution, this paper proposes a remote sensing evaluation method of watershed ecological restoration effect, so as to monitor the implementation effect of ecological restoration engineering in the watershed and technically check whether the expected goals set before the restoration are achieved. The comprehensive ecological restoration engineering of Yongding River has been implemented since 2016, and it was the first focus of the coordinated development of Beijing-Tianjin-Hebei region to make advances in ecology. In this paper, year 2015 and 2020 were selected as the before and the after the ecological restoration engineering of Yongding River. The research object was the riparian zone from Luopoling Reservoir to Daning Reservoir in Yongding River Watershed. After obtaining and processing remote sensing images, ZY-3 images were used to obtain land cover data by means of human-computer interactive interpretation, and Landsat images were used to retrieve NDVI data. Based on these data, the changes of the eight indicators of water resources, water ecology and ecological function in the study area were calculated to evaluate the ecological restoration engineering effect. The results showed that the study area has basically realized the maintenance of ecological water quantity, formed the ecological corridor of Yongding River, and effectively enhanced the ecological function and improved the water environment. By verifying the feasibility of remote sensing evaluation method, this paper could provide relevant decision makers and planners with an effective evaluation method for the ecological restoration engineering effect based on remote sensing data and technology. • Remote sensing images and land cover data were utilized to calculate the indicators before and after ecological restoration. • Ecological restoration engineering effect was evaluated from water resources, water environment and ecological function. • Based on the proposed method, the ecological restoration effect in the study area was proved to be satisfactory overall. [ABSTRACT FROM AUTHOR]