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关键词： Signal processing   Autonomous aerial vehicles   Special issues and sections   Conferences   Computer science   6G mobile communication   5G mobile communication  

摘要： The current development of 5G networks represents a breakthrough in the design of communication networks, for its ability to provide a single platform enabling a wide variety of data services. With these significant enhancements enabled by 5G, it is already possible to envision the needs towards 6G. Providing "connectivity from the sky" is one innovative trend for upcoming 6G communication systems. Satellites, high and low altitude platforms (HAP and LAP), drones, aircrafts, and airships are being considered as candidates for deploying wireless communications complementing terrestrial communications. Combining these network elements, Aerial Access Networks (AANs) have attracted significant attention from both academia and industry, and are recognized as a candidate solution for 6G communications. AANs are heterogeneous networks that are engineered to utilize satellites, HAPs, and LAPs to build network access platforms. Unlike terrestrial wireless networks, AANs are characterized by dynamic, thus frequently changed, network topologies and more vulnerable communication connections. However, AANs are not intended to replace the existing technologies, but instead to work with them in a complementary and integrated fashion. Therefore, AANs are accompanied with the demand for seamless integration of heterogeneous networks, such that the network Quality-of-Service (QoS) can be improved. Therefore, it is essential to develop new communications, signal processing, and optimization approaches to accommodate diverse services and applications with different QoS requirements in various scenarios.

关键词： History   Capital punishment   National Socialism  

摘要： Introduction: During the times of National Socialism, Berlin anatomist Hermann Stieve had access to many bodies of executed women for his histological research on reproductive organs. Newly emerged sources add to our knowledge of this research and allow a critical examination of some of Stieve's post-war claims. Sources: Descendants of Stieve have preserved more than 200 dissection protocols in Stieve's own hand, which are now held at the archive of Humboldt University in Berlin. In addition, a list of names of execution victims related to this research has been newly identified at the Federal Archive in Berlin. Results: The 207 protocols mostly relate to women executed in Berlin Plotzensee from March 1942 onwards and include two women executed after the war in January 1947. Other sources show that bodies of executed men were delivered to the institute of anatomy until November 1950. The documents confirm that Stieve did not use only the bodies of "Schwerverbrecher [felons]" as he had asserted in 1952. They do verify some of Stieve's post war claims, like that he had access to court records of the victims and likely also to information from attending doctors and family members, if only in rare cases. Discussion: The anatomists' access to bodies of the executed continued after 1945 as this practice was not seen as something Nazi-typical by the allied authorities. Hermann Stieve's post-war defence strategy can be characterised by an "economic" handling of the truth, avoiding outright lies by making true statements on rare cases which, however, were not representative of his general course of actions.(c) 2022 Elsevier GmbH. All rights reserved.

关键词： Co-culture   Stocking density   Penaeus monodon   Gracilaria tenuistipitata   Yield   Feed cost  

摘要： A pilot-scale experiment was conducted within an improved extensive pond to evaluate the efficiency of co-culturing black tiger shrimp (Penaeus monodon) and red seaweed (Gracilaria tenuistipitata) at different densities with partially reduced feed rations. Six treatments were established at random in triplicate with three stocking densities (2, 4, and 6 ind. m(-2)), and each density monocultured with either a 100% feed ration or co-cultured with red seaweed and a 50% feed ration. The culture system consisted of eighteen net enclosures (16 m(2) each) installed in an improved extensive pond. After 4 months of culture, the growth rates of the shrimp decreased with increasing stocking density and shrimp yields at densities of 4 and 6 ind. m(-2) were similar to each other (p > 0.05) and significantly higher (p < 0.05) than at a density of 2 ind. m(-2). Notably, the growth rates, survival, and yield of shrimp in co-culture receiving a 50% feed ration were comparable to, and feed conversion ratio and feed cost were much lower than those in monoculture receiving a 100% feed ration at the same stocking density. The proximate composition of the shrimp meat in terms of moisture and protein levels was nearly equivalent in all treatments, while co-culture groups had lower lipid and higher ash content than monoculture groups. The results revealed that a co-culture of black tiger shrimp and red seaweed at a density of 4 ind. m(-2) with a 50% feed ration maintained normal growth and increased shrimp yield while saving 40.45% of feed costs compared with monoculture.

关键词： Ethics   Computer Ethics   Teaching Computer Ethics   Computer Science Education  

摘要： Within the Computer Science community, many ethical issues have emerged as significant and critical concerns. Computer ethics is an academic field in its own right and there are unique ethical issues associated with information technology. It encompasses a range of issues and concerns including privacy and agency around personal information, Artificial Intelligence and pervasive technology, the Internet of Things and surveillance applications. As computing technology impacts society at an ever growing pace, there are growing calls for more computer ethics content to be included in Computer Science curricula. In this paper we present the results of a survey that polled faculty from Computer Science and related disciplines about teaching practices for computer ethics at their institutions. The survey was completed by respondents from 61 universities across 23 European countries. Participants were surveyed on whether or not computer ethics is taught to Computer Science students at each institution, the reasons why computer ethics is or is not taught, how computer ethics is taught, the background of staff who teach computer ethics and the scope of computer ethics curricula. This paper presents and discusses the results of the survey.

关键词： Approximation algorithms   Unmanned aerial vehicles   Throughput   Base stations   Computer science   IEEE transactions   Urban areas   UAV networks   emergent communication   connected maximum throughput problem   approximation algorithms   distributed resource allocation and provisioning  

摘要： In this paper we study the deployment of multiple unmanned aerial vehicles (UAVs) to form a temporal UAV network for the provisioning of emergent communications to affected people in a disaster zone, where each UAV is equipped with a lightweight base station device and thus can act as an aerial base station for users. Unlike most existing studies that assumed that a UAV can serve all users in its communication range, we observe that both computation and communication capabilities of a single lightweight UAV are very limited, due to various constraints on its size, weight, and power supply. Thus, a single UAV can only provide communication services to a limited number of users. We study a novel problem of deploying K UAVs in the top of a disaster area such that the sum of the data rates of users served by the UAVs is maximized, subject to that (i) the number of users served by each UAV is no greater than its service capacity;and (ii) the communication network induced by the K UAVs is connected. We then propose a 1-1/e/[root K]-approximation algorithm for the problem, improving the current best result of the problem by five times (the best approximation ratio so far is 1-1/e/5( root K +1)), where e is the base of the natural logarithm. We finally evaluate the algorithm performance via simulation experiments. Experimental results show that the proposed algorithm is very promising. Especially, the solution delivered by the proposed algorithm is up to 12% better than those by existing algorithms.

关键词： Citizen science   Computer vision   Electricity access   Rural mapping   Satellite imagery   Remote sensing  

摘要： To implement effective rural electricity access systems, it is fundamental to identify where potential consumers live. Here, we test the suitability of citizen science paired with satellite imagery and computer vision to map remote off-grid homes for electrical system design. A citizen science project called "Power to the People " was completed on the Zooniverse platform to collect home annotations in Uganda, Kenya, and Sierra Leone. Thou-sands of citizen scientists created a novel dataset of 578,010 home annotations with an average mapping speed of 7 km(2)/day. These data were post-processed with clustering to determine high-consensus home annotations. The raw annotations achieved a recall of 93% and precision of 49%;clustering the annotations increased precision to 69%. These were used to train a Faster R-CNN object detection model, producing detections useful as a first pass for home-level mapping with a feasible mapping rate of 42,938 km(2)/day. Detections achieved a precision of 67% and recall of 36%. This research shows citizen science and computer vision to be a promising pipeline for accelerated rural home-level mapping to enable energy system design.

关键词： digital culture bearing   Black women travel influencers   Instagram  

摘要： This study examines how travel influencers Jessica Nabongo and Oneika Raymond use Instagram in a process I call "digital culture bearing," employing the platform to nurture wisdom about Africa. They combine images, captions, hashtags, and geotags to share information about nations within the African continent with principally Black populations. Employing critical technocultural discourse analysis (CTDA) to interpret how race, gender, global travel, and cultural knowledge promotion intersect within Instagram, the study analyzes the platform and practices of digital culture bearing, theorizing new ways of understanding how Black women situate themselves in Africa for their online networks. Ultimately, the study offers considerations of what it means to be a culture bearer in the twenty-first century digi-sphere and articulates new conceptualizations of Black internationalism within social networking sites.

关键词： Third reich   Capital punishment   Critical discourse analysis   Executioners   Critical theory   Obedience   Application letter  

摘要： This article presents an empirical investigation into the construction of obedience in letters of applications mailed to National Socialist authorities for the position of executioner between the years 1933 and 1945. To this end, a corpus of 178 letters of application was compiled, annotated, and analyzed using the corpus analysis toolkits Antconc and Lancsbox. A quantitative and qualitative analysis of the corpus was conducted. The findings were related to and interpreted from the perspectives of applied legal linguistics, stylistics, and legal history. The project aims to explore the construction of a shared discourse of obedience and how this discourse is operative in the letters of application. Drawing on an explorative interdisciplinary framework, this project seeks to answer the following research questions: Is obedience a construct in applicants' letters of motivation? Which linguistic devices and discursive strategies are used by the executioners to express submission to officials of the National Socialist state? Are there variants of the construction of submission by applicants?

关键词： Academic speaking   Move analysis   Conference discussion sessions   Question types   Corpus analysis   Computer science  

摘要： Asking questions and making comments in conference Q&A sessions can be challenging for novice academics. Discussants not only try to seek answers or exchange ideas with the presenter but also endeavour to project a positive image of themselves by asking the 'right' questions in the 'right' way. However, many novice academics fear looking foolish because of unfocused and convoluted questions. Surprisingly, little guidance is available for how to formulate Q&A questions. This study attempts to address the gap by investigating the forms, functions and generic moves of 268 turns taken by discussants in 80 computer science conference Q&A sessions. Certain forms (i.e., question and comment) were found to be associated with certain pragmatic functions. This study reveals that different types of question/comment have major moves in common. The study also shows that the more evaluative and face-threatening the question is, the more important it is for the discussant to make the moves of building rapport with the presenter, and contextualising and justifying the main question/statement. The importance of justifying the main question/ statement also resonates with the persuasive nature of scientific argumentative discourse. The findings can offer novice academics detailed explanations of the communicative purposes and strategies for this important conference interaction. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Data models   Data visualization   Bioinformatics   Pollution measurement   Dimensionality reduction   Computer science   Clustering algorithms   Low rank representation   correntropy   clustering   gene markers   single cell RNA-sequencing  

摘要： The exploration of single cell RNA-sequencing (scRNA-seq) technology generates a new perspective to analyze biological problems. One of the major applications of scRNA-seq data is to discover subtypes of cells by cell clustering. Nevertheless, it is challengeable for traditional methods to handle scRNA-seq data with high level of technical noise and notorious dropouts. To better analyze single cell data, a novel scRNA-seq data analysis model called Maximum correntropy criterion based Non-negative and Low Rank Representation (MccNLRR) is introduced. Specifically, the maximum correntropy criterion, as an effective loss function, is more robust to the high noise and large outliers existed in the data. Moreover, the low rank representation is proven to be a powerful tool for capturing the global and local structures of data. Therefore, some important information, such as the similarity of cells in the subspace, is also extracted by it. Then, an iterative algorithm on the basis of the half-quadratic optimization and alternating direction method is developed to settle the complex optimization problem. Before the experiment, we also analyze the convergence and robustness of MccNLRR. At last, the results of cell clustering, visualization analysis, and gene markers selection on scRNA-seq data reveal that MccNLRR method can distinguish cell subtypes accurately and robustly.