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关键词： Germanium   Silicon   Avalanche photodiodes   Electric fields   Breakdown voltage   Voltage measurement   Standards   PIN photodiodes   Computer science   Avalanche breakdown   GeSn avalanche photodiode   infrared photodetector   multiplication gain   thin Ge buffer  

摘要： We demonstrate monolithically grown germanium-tin (GeSn) on silicon avalanche photodiodes (APDs) for infrared light detection. A relatively thinner Ge buffer design was adopted to allow effective photo carriers to transport from the GeSn absorber to the Si multiplication layer such that clear punch-through behavior and a saturated primary responsivity of 0.3 A/W at 1550 nm were observed before avalanche breakdown in GeSn/Si APDs for the first time. The spectral response covers 1500 to 1700 nm. The measured punch-through and breakdown voltages are 15 and 17 V, respectively. Undisputed multiplication gain was obtained with the maximum value of 4.5 at 77 K, and 1.4 at 250 K, directly in reference to the saturated primary responsivity from the same device rather than a different GeSn p-i-n photodiode in previous reports. A peak responsivity was measured as 1.12 A/W at 1550 nm and 77 K.

关键词： Anomaly detection   Correlation   Feature extraction   Computer science   Vectors   Transformers   Software   Semantics   Reviews   Representation learning   Graph anomaly detection   graph neural networks   canonical correlation analysis   graph embedding  

摘要： In unsupervised graph anomaly detection, existing methods usually focus on detecting outliers by learning local context information of nodes, while often ignoring the importance of global context. However, global context information can provide more comprehensive relationship information between nodes in the network. By considering the structure of the entire network, detection methods are able to identify potential dependencies and interaction patterns between nodes, which is crucial for anomaly detection. Therefore, we propose an innovative graph anomaly detection framework, termed CoCo (Context Correlation Discrepancy Analysis), which detects anomalies by meticulously evaluating variances in correlations. Specifically, CoCo leverages the strengths of Transformers in sequence processing to effectively capture both global and local contextual features of nodes by aggregating neighbor features at various hops. Subsequently, a correlation analysis module is employed to maximize the correlation between local and global contexts of each normal node. Unseen anomalies are ultimately detected by measuring the discrepancy in the correlation of nodes' contextual features. Extensive experiments conducted on six datasets with synthetic outliers and five datasets with organic outliers have demonstrated the significant effectiveness of CoCo compared to existing methods.

关键词： African American   Black press   consumer culture   race   gender  

摘要： This article traces the early origins of Black consumer culture as it was portrayed in the Black press from the late 1800s to the early 1920s. It argues that Black newspapers were important agents in shaping how African Americans conceived of and interacted with the evolving commercial sphere around the turn of the century. Papers such as the Pittsburgh Courier, the Broad Ax, the Tulsa Star, and many others celebrated participation in the consumer arena as a respectable and desired practice. They also distinguished between shopping, as a social feminine pursuit, and patronizing Black-owned businesses, which was perceived as a gender-neutral, or even manly, racial duty. Espousing African American elite ideologies such as racial uplift and self-help, Black editors presented any purchasing of goods as an upright activity, which adorned its performer with affluence, respect, and power. Such portrayal encouraged the participation of African Americans in the consumer sphere and implied that it was an arena of similarity rather than difference.

关键词： Security   Authentication   Protocols   Vehicular ad hoc networks   Privacy   Cryptography   Electronic mail   Resists   Computer science   Transportation   VANET   smart contract   blockchain   conditional privacy-preserving authentication   security and privacy   trust management  

摘要： Intelligent Transportation Systems (ITS) dwell on Vehicular Ad-hoc NETworks (VANETs) for message dissemination to achieve the goal of traffic safety and efficiency. VANETs achieve communication among vehicles and roadside units via wireless communication. Hence, security and privacy are significant concerns to be addressed for an effective application of secure VANETs in any ITS. Researchers have addressed these issues with trust management-based schemes or cryptography-based schemes. While these schemes can secure VANETs, they have various limitations presenting hindrances in their deployment. In this context, we have proposed a Blockchain-assisted Trust Computation with a Conditional Privacy-preserving Authentication (BTC2PA) scheme for connected vehicles. The BTC2PA scheme uses a blockchain (Ethereum) assisted PKI infrastructure with digital signatures to achieve authentication for secure communication. Furthermore, it integrates a trust score computation scheme based on a reward and punishment mechanism to provide resistance against internal attacks. The feasibility and validity of the proposed BTC2PA scheme have been studied by implementation work in Rinkeby (Ethereum test network) and extensive simulations using NS-3. The results obtained show that the proposed BTC2PA scheme meets the security and privacy requirements while significantly improving the performance metrics such as communication, storage, computation cost, and end-to-end delay when compared to existing schemes.

关键词： Forecasting   Time series analysis   Benchmark testing   Transformers   Predictive models   Data models   Computer science   Reliability   Proposals   Electricity   Benchmarking   multivariate time series   spatial-temporal forecasting   long-term time series forecasting  

摘要： Multivariate Time Series (MTS) analysis is crucial to understanding and managing complex systems, such as traffic and energy systems, and a variety of approaches to MTS forecasting have been proposed recently. However, we often observe inconsistent or seemingly contradictory performance findings across different studies. This hinders our understanding of the merits of different approaches and slows down progress. We address the need for means of assessing MTS forecasting proposals reliably and fairly, in turn enabling better exploitation of MTS as seen in different applications. Specifically, we first propose BasicTS+, a benchmark designed to enable fair, comprehensive, and reproducible comparison of MTS forecasting solutions. BasicTS+ establishes a unified training pipeline and reasonable settings, enabling an unbiased evaluation. Second, we identify the heterogeneity across different MTS as an important consideration and enable classification of MTS based on their temporal and spatial characteristics. Disregarding this heterogeneity is a prime reason for difficulties in selecting the most promising technical directions. Third, we apply BasicTS+ along with rich datasets to assess the capabilities of more than 30 MTS forecasting solutions. This provides readers with an overall picture of the cutting-edge research on MTS forecasting.

关键词： Games   Collaboration   Social networking (online)   Mathematical models   Complexity theory   Roads   Computer science   Vectors   Urban areas   Time factors   Cooperation   non-cooperative game   temporal network   time limitation  

摘要： Temporal networks are obtained from time-dependent interactions among individuals, whereas the interactions can be emails, phone calls, face-to-face meetings, or work collaboration. In this article, a temporal game framework is established, in which interactions among rational individuals are embedded into two-player games in a time-dependent manner. This allows studying the time-dependent complexity and variability of interactions, and the way they affect prosocial behaviors. Based on this simple mathematical model, it is found that the level of cooperation is promoted when the time of collaboration is equally limited for every individual. This observation is confirmed by a series of systematic human experiments on over 1,400 subjects, forming a foundation for comprehensively describing human temporal interactions in collaboration. The research results reveal an important incentive for human cooperation, leading to a better understanding of a fascinating aspect of human nature in society.

关键词： Computer Science   Computer Software   Computer Technology   Areas Of Expertise   Editorial Board   Software Engineering   Relevant Content   Peer Review Process   Technological Domains   Diversity And Inclusion  

关键词： deeper learning   foreign languages   learning science   computer science   scientific knowledge mapping  

摘要： Deeper learning (DL) is firmly rooted in learning science and computer science. However, a dearth of review studies has probed its trajectory in DL in foreign languages(DLFL). Utilizing SSCI from the Web of Science Core Collection, we employ Citespace and Vosviewer to analyze the scientific knowledge graph of DLFL literature. Our analysis elucidates its geographical spread over time, highlights critical areas for further research, and identifies current trends in its evolution. The results show that DLFL research advances with the United States, China, the United Kingdom, Spain, and Australia ranking in the top five in terms of the number of articles published;the research hotspots focus on factors influencing DLFL, learners' cognitive processes through language acquisition and information technology intervention in DLFL. The field of DLFL pertains to learning science, which is dedicated to enhancing learners' performance, while computer science emphasizes utilizing advanced educational technologies as intervention tools. From learning science to computer science, both fields have followed distinct paths in their respective developments with a trend of integration, and the latter provided the former with a continuous supply of technology-mediated educational tools, including the future uses of computational thinking and ChatGPTs. As for future research directions, the development trajectory of DLFL will focus on natural language processing, cognitive neuroscience, and artificial intelligence. The findings will offer insights for future research on DLFL by enhancing the informational and computational literacy of both instructors and learners, empowering them to navigate and leverage the transformative potential of DLFL.

关键词： Optimization   Maintenance engineering   Linear programming   Tuning   Computer science   Pareto optimization   Software   Evolutionary computation   Chatbots   Vectors   Adaptive transformation   auxiliary function   constrained optimization   many-objective optimization  

摘要： Transforming a constrained optimization problem (COP) into a multi/many-objective optimization problem (MOP/MaOP) represents a practical approach for solving COPs. This article introduces an adaptive multi/many-objective transformation technique, termed adaptive many-objective transformation technique (AMaOTCO), designed to effectively address COPs. The transformed many-objective optimization problem (MaOP) defines an objective using a convex combination of the objective function (or constraint violation function) and an auxiliary function. This auxiliary function is constructed through a convex combination of the objective function and a weighted constraint violation function. The adaptive tuning of all combination coefficients is based on population information. This adaptive tuning ensures an intelligent balance between minimizing various constraint violations and managing the tradeoff between objective function minimization and constraint violation reduction. The effectiveness of the proposed AMaOTCO is demonstrated through comparisons with state-of-the-art constrained evolutionary algorithms (CEAs) on a set of real-world COPs.