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This study examines the interlinkages between the South Atlantic Ocean Dipole (SAOD) and Central Africa (CA) rainfall variability from June to August, spanning from 1981 to 2018, using observational and reanalysis datasets. The results show that during positive SAOD events termed pSAOD, positive (negative) rainfall anomalies feature the southwestern CA termed zone I (the rest of CA landmass, termed zone II) more pronounced in reanalysis data. The reverse rainfall anomalies' pattern characterises negative SAOD events termed nSAOD. The relationship between CA rainfall variability and SAOD strengthens when the signal of El Niño-Southern Oscillation (ENSO) is removed. However, the impact of ENSO on the SAOD is contrasted between the northern and southern CA, so that ENSO compensates for the reduced rainfall associated with the SAOD north of 10°N. South of 10°N, ENSO attenuates wetness over the southwestern zone, and reinforces the dryness over the southeastern zone. During the pSAOD events, increased precipitation is associated with increased moisture convergence over zone I, with advection originating from neighbouring oceanic regions. At the same time, convergent moisture towards zone II is weak and recirculates towards southern Africa and does not contribute to moistening the region. However, during nSAOD, zone I instead experiences strong moisture divergence, whereas zone II is a sink of moisture convergence originating from zone I and from Sahelian and west African regions. In general, the atmospheric circulation seems better developed throughout the tropospheric column during nSAOD events than during pSAOD events and would suggest strong modulating impacts of regional-and local-scale processes in the rainfall variability. [ABSTRACT FROM AUTHOR]

This paper presents a chaotic Arnold map (CAM)-based selective encryption (SE) bitstream cipher for the scalable High-Efficiency Video Coding (SHVC). The proposed CAM-based SHVC-SE bitstream cipher employs the CAM for ciphering the coefficients sign bits of Discrete Cosine Transform (DCT), the Motion Vector Difference (MVD) and Sample Adaptive Offset (SAO). The proposed CAM-based SHVC-SE bitstream cipher is designed with the potential of encrypting the SHVC mostly sensitive information bits while preserving the video format compliance characteristic. The performance of the proposed CAM-based SHVC-SE bitstream cipher is compared to with the AES-based SHVC SE in CFB operation mode. The achieved outcomes demonstrates the advantage of employing the CAM in the proposed CAM-based SHVC-SE bitstream cipher that results in decreasing the encoding time for the proposed CAM-based SHVC-SE bitstream cipher compared with the AES-based SHVC SE in in CFB operation mode. Security tests on the proposed CAM-based SHVC-SE bitstream cipher are carried out for testing the robustness of the proposed CAM-based SHVC-SE bitstream cipher against attacks. The results of security tests demonstrated and confirmed the efficiency of the proposed CAM-based SHVC-SE bitstream cipher. [ABSTRACT FROM AUTHOR]

This paper presents TeknoAssistant, a domain-specific tech mining method for building a problem–solution conceptual network aimed at helping technicians from a particular field to find alternative tools and pathways to implement when confronted with a problem. We evaluate our approach using Natural Language Processing field, and propose a 2-g text mining process adapted for analyzing scientific publications. We rely on a combination of custom indicators with Stanford OpenIE SAO extractor to build a Bernoulli Naïve Bayes classifier which is trained by using domain-specific vocabulary provided by the TeknoAssistant user. The 2-g contained in the abstracts of a scientific publication dataset are classified in either "problem", "solution" or "none" categories, and a problem–solution network is built, based on the co-occurrence of problems and solutions in the abstracts. We propose a combination of clustering technique, visualization and Social Network Analysis indicators for guiding a hypothetical user in a domain-specific problem solving process. [ABSTRACT FROM AUTHOR]

The text-based patent analysis is grounded in information extraction technique. However, such technique suffers from obvious defects such as low degree of automation and unsatisfactory extraction accuracy. To deal with these problems, after an information schema is pre-defined, which contains 17 types of entities and 15 types of semantic relations, a dataset of 1010 patent abstracts is annotated and opened freely to the research community. Then, a novel patent information extraction framework is proposed, in which two deep-learning models, BiLSTM-CRF and BiGRU-HAN, are respectively used for entity identification and semantic relation extraction. Finally, to demonstrate the advantages of the new framework, extensive experiments are conducted, and the SAO method and PCNNs model are taken as respective baselines on the framework and module levels. Experimental results show that our framework out-performs the traditional one in terms of automation and accuracy, and is capable of extracting fine-grained structured information from patent texts. [ABSTRACT FROM AUTHOR]

The Smithsonian Astrophysical Observatory (SAO) and the Centre National d'Études Spatiales (CNES) worked closely together in the early years of the space program to deploy satellite laser ranging (SLR) systems at overseas sites to enhance global coverage to support specific missions. The data were routinely made available for use by the science community for programs in geodesy, gravity field, atmospheric physics, and ultimately for oceanography and geodynamics. SAO and CNES organized campaigns for international participation and loaned each other equipment to enhance the network. SAO and CNES provided technical expertise and advice to a number of other groups as they planned and deployed SLR systems. In this paper, we will discuss the history and the role of the two institutions in the building of the international SLR network. [ABSTRACT FROM AUTHOR]

This paper presents a novel filtering technique based on sample adaptive offset (SAO) in H.265/high-efficiency video coding (HEVC) for reduction in the temporal flickering artifacts and improving the coding performance. SAO is a newly introduced technique for in-loop filtering in H.265/HEVC, which derives the offsets independently for each frame in the spatial domain without considering temporal frame correlation. As a result, the temporal distortion artifacts which will have a negative effect on the subjective quality, such as flickering artifacts, cannot be effectively addressed. In this paper, the rate-distortion optimization of the newly developed SAO method, referred to as Inter-SAO, is performed on the residual samples between adjacent frames. Inter-SAO and SAO in the reference software of H.265/HEVC (i.e., the test model HM) are then combined to form the novel in-loop filter-based method, denoted as 3D-SAO filtering method, where both spatial information and temporal information are effectively utilized to reduce the overall distortion in reconstructed videos. Compared with the SAO in HM, 3D-SAO has demonstrated its advanced performance for flickering artifacts suppression. Furthermore, 3D-SAO improves the coding efficiency compared with the SAO in HM with a performance gain of up to 0.91 dB in $$\Delta PSNR$$ , 1.74 dB in $$\Delta PSPNR$$ and 7.33 % in BD-rate reduction. [ABSTRACT FROM AUTHOR]

This paper proposes a framework to identify and evaluate companies from the technological perspective to support merger and acquisition (M&A) target selection decision-making. This employed a text mining-based patent map approach to identify companies which can fulfill a specific strategic purpose of M&A for enhancing technological capabilities. The patent map is the visualized technological landscape of a technology industry by using technological proximities among patents, so companies which closely related to the strategic purpose can be identified. To evaluate the technological aspects of the identified companies, we provide the patent indexes that evaluate both current and future technological capabilities and potential technology synergies between acquiring and acquired companies. Furthermore, because the proposed method evaluates potential targets from the overall corporate perspective and the specific strategic perspectives simultaneously, more robust and meaningful result can be obtained than when only one perspective is considered. Thus, the proposed framework can suggest the appropriate target companies that fulfill the strategic purpose of M&A for enhancing technological capabilities. For the verification of the framework, we provide an empirical study using patent data related to flexible display technology. [ABSTRACT FROM AUTHOR]

Companies should investigate possible patent infringement and cope with potential risks because patent litigation may have a tremendous financial impact. An important factor to identify the possibility of patent infringement is the technological similarity among patents, so this paper considered technological similarity as a criterion for judging the possibility of infringement. Technological similarities can be measured by transforming patent documents into abstracted forms which contain specific technological key-findings and structural relationships among technological components in the invention. Although keyword-based technological similarity has been widely adopted for patent analysis related research, it is inadequate for identifying patent infringement because a keyword vector cannot reflect specific technological key-findings and structural relationships among technological components. As a remedy, this paper exploited a subject-action-object (SAO) based semantic technological similarity. An SAO structure explicitly describes the structural relationships among technological components in the patent, and the set of SAO structures is considered to be a detailed picture of the inventor's expertise, which is the specific key-findings in the patent. Therefore, an SAO based semantic technological similarity can identify patent infringement. Semantic similarity between SAO structures is automatically measured using SAO based semantic similarity measurement method using WordNet, and the technological relationships among patents were mapped onto a 2-dimensional space using multidimensional scaling (MDS). Furthermore, a clustering algorithm is used to automatically suggest possible patent infringement cases, allowing large sets of patents to be handled with minimal effort by human experts. The proposed method will be verified by detecting real patent infringement in prostate cancer treatment technology, and we expect this method to relieve human experts' work in identifying patent infringement. [ABSTRACT FROM AUTHOR]

Owing to the importance of middle atmosphere, recently, a Middle Atmospheric Dynamics (MIDAS) program was carried out during the period 2002-2007 at Thumba (8.5°N, 77°E). The measurements under this program, involving regular radiosonde/rocket flights as well as atmospheric radars, provided long period observations of winds and temperature in the middle atmospheric region from which waves and oscillations as well as their forcing mechanisms particularly in the low-latitude middle atmosphere could be analyzed. However, a detailed analysis of the forcing mechanisms remains incomplete due to the lack of important measurements like ozone which is a significant contributor to atmospheric dynamics. Presently, profiles of ozone are available from TIMED/SABER (Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics/Sounding of the Atmosphere using Broad Emission Radiometry) satellite globally from about 15 to 100 km, over multiple years since 2002. In this regard, a comprehensive study has been carried out on ozone and its variability at Quasi Biennial Oscillation (QBO) and Semiannual Oscillation (SAO) scales using TIMED/SABER ozone observations during the MIDAS campaign period. Before using the TIMED/SABER ozone measurements, an inter-comparison has been carried out with in situ measurements of ozone obtained under the Southern Hemisphere Additional Ozonesondes (SHADOZ) campaign for the year 2007 at few stations. The inter-comparison showed very good agreement between SABER and ozonesonde derived ozone profiles. After validating the SABER observations, ozone profiles are used extensively to study the QBO and SAO along with temperature and winds in the 20-100 km height region. It is known that the SAO in mesosphere and stratosphere are in opposite phases, but the present study for the first time reports the aspect of opposite phases in the mesosphere itself. Thus, the present work attempts to study the long-period oscillations in stratosphere and mesosphere in ozone, temperature and winds simultaneously for the first time over this latitude. These observations provided a unique opportunity to explore long-period oscillations in chemistry, dynamics and thermal structure of the middle atmosphere simultaneously. [ABSTRACT FROM AUTHOR]

Southeast Asian ovalocytosis (SAO) is a red blood cell abnormality common in malaria-endemic regions and caused by a 27 nt deletion of the band 3 protein gene. Since band 3 protein, also known as anion exchanger 1, is expressed in renal distal tubules, the incidence of SAO was examined in distal renal tubular acidosis (dRTA) in Malays in Kelantan, Malaysia. Twenty-two patients with dRTA and 50 healthy volunteers were examined for complication of SAO by both morphological and genetic analyses. SAO was identified in 18 of the 22 dRTA patients (81.8%), but only two of the 50 controls (4%). The incidence of SAO was significantly high in those with dRTA (p<0.001), indicating a dysfunctional role for band 3 protein/anion exchanger 1 in the development of dRTA. [ABSTRACT FROM AUTHOR]

Counselors, faculty, and student personnel specialists are often unaware that college students are experiencing serious academic or adjustment difficulties until it is too late to rectify the problem. Most universities would benefit from an early warning system that detects at-risk students before performance or social problems jeopardize their college careers. This investigation demonstrated that scores from the Survey of Academic Orientations (SAO) were predictive of first-semester freshmen grades. Subsequent analysis showed that the SAO significantly improved the prediction of grade point averages, after taking the effects of Scholastic Assessment Test scores and high school percentage rank into consideration. The SAO gives educators a new early warning device, a way to identify those undergraduates most at risk of receiving poor grades. The next steps in the research process are to: (1) assess the relationship of SAO scores to other important academic indexes, such as retention and student stress, and (2) determine if furnishing counselors and other college personnel with SAO scores is of therapeutic value. [ABSTRACT FROM AUTHOR]

An assessment of satellite-derived long-term tropospheric nitrogen dioxide (NO2) data is performed over the Indian region and their implications on the regional air quality are discussed. The Indo-Gangetic plain (IGP) shows an increasing trend in NO2 of the order of 3×1013mol/cm2/yr. The pixel-wise (0.25 km) trend for the period 2005-2014 reveals various regions having increased rates of pollution over the study period. Further, the mean seasonal concentrations of NO2 are segregated for different parts of the country including oceanic regions and the trends are brought out. The highest rate of increase of tropospheric NO2(2×1014mol/cm2/yr) is seen around coal mining areas and certain industrial areas such as ports and thermal power stations. Using the data spanning 10 years, the wavelet analysis is carried out to study the influence of semi-annual oscillations (SAO) on trace gas concentrations in different parts of the country. The study reveals that the SAO are stronger in the northern parts of India, including IGP and western India, whereas South India and oceanic regions are having very low SAO component and strong annual oscillation component. [ABSTRACT FROM AUTHOR]