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关键词： Investment   Search problems   Social networking (online)   Computer science   Heuristic algorithms   Companies   Spread spectrum communication   Attractive individual   attractive group   dynamic information network   difference graph  

摘要： Analyzing dynamic information networks, which contain evolving objects and links, to meet users' various needs has attracted much attention in recent years. For sales companies, recruiting staff who are socialites would help to increase sales volume since such staff often sell more. For universities, employing active collaborators who are productive and well connected to many different scholars over time could bring many benefits to their development. However, no previous work has focused on the discovery of socialites and active collaborators who are worthy of investment in reality. In this paper, we advocate a new concept of attractive individuals to model such special objects. We also introduce the concept of attractive groups to represent groups of well-connected attractive individuals. We analyze the complexity of the attractive individual and group search problems. A time and space efficient algorithm is presented to detect attractive individuals. Furthermore, three algorithms are respectively proposed to find top-$k$k representative attractive groups. Experiments on 6 real-world datasets show high performance of our methods and the significance of attractive individuals and groups in reality.

关键词： 略阳乌鸡   放养模式   养殖成本   效益  

摘要： [目的]研究放养模式下略阳乌鸡不同阶段养殖成本效益。[方法]选用在陕西省汉中市略阳县龙昊乌鸡种源繁育中心放养的1 200只略阳乌鸡肉鸡,通过常规饲养试验,测定和记录5个饲养阶段(1~42、43~60、61~90、91~120、121~150日龄)试验鸡的增重、饲料饲喂量、免疫成本、人工成本及试验鸡成活率等,分析其生长发育规律,同时结合当地市场价格及各项成本综合分析略阳乌鸡肉鸡养殖的最大经济效益及产生该效益的日龄。[结果]42日龄略阳乌鸡公鸡体重高于母鸡,但差异性不显著;其他各阶段略阳乌鸡公鸡体重极显著高于母鸡,随着鸡群日龄的增加,料肉比也不断升高;在整个饲养周期内,试验鸡在1~42日龄阶段料肉比最低,1~90日龄阶段单位养殖利润最高,1~120日龄阶段平均每只鸡养殖利润最高。[结论]在市场价格稳定的情况下,略阳乌鸡饲养周期在120日龄左右能获得最大养殖效益。

关键词： 批评性话语分析   政治话语   系统功能语言学   就职演讲  

摘要： 随着经济全球化纵深发展,国际话语权逐渐成为衡量各国国际地位的重要工具。政治话语作为国际话语中的特殊部分,往往蕴含着浓厚的意识形态色彩。批评性话语分析属于现代语言学和话语分析的分支,主要以Halliday系统功能语法为理论基础,主张在社会背景下剖析各类大众话语。目前有许多研究聚焦于种族歧视类新闻话语分析且已趋向成熟。本文选取美国总统Donald Trump和Joe Biden的就职演讲,以系统功能语法中及物性、转换、情态和分类为工具进行批评性话语分析,旨在揭示政治话语与意识形态之间的关系。

关键词： Students  

摘要： Although different organizations have defined policies towards diversity in academia, many argue that minorities are still disadvantaged in university admissions due to biases. Extensive research has been conducted on detecting partiality patterns in the academic community. However, in the last few decades, limited research has focused on assessing gender and nationality biases in graduate admission results of universities. In this study, we collected a novel and comprehensive dataset containing information on approximately 14,000 graduate students majoring in computer science (CS) at the top 25 North American universities. We used statistical hypothesis tests to determine whether there is a preference for students' gender and nationality in the admission processes. In addition to partiality patterns, we discuss the relationship between gender/nationality diversity and the scientific achievements of research teams. Consistent with previous studies, our findings show that there is no gender bias in the admission of graduate students to research groups, but we observed bias based on students' nationality. © 2023, CC BY.

关键词： Islamic geometric patterns   Structural   Sustainable   Aesthetic-based principles   Application-based principles   Computer science  

摘要： Currently, there is a tendency to use Islamic Geometric Patterns (IGPs) as important identities and cultural elements of building design in the Middle East. Despite high demand, lack of information about the potential of IGPs principles have led to formal inspiration in the design of existing buildings. Many research studies have been carried out on the principles of IGPs. However, comprehensive studies relating to new possibilities, such as structure-based, sustainable-based, and aesthetic-based purposes, developed by computer science and related technologies, are relatively rare. This article reviews the state-of-the-art knowledge of IGPs, provides a survey of the main principles, presents the status quo, and identifies gaps in recent research directions. Finally, future prospects are discussed by focussing on different aspects of the principles in accordance with collected evidence obtained during the review process.

关键词： philosophy of science   semantics   metaphor   analogy   Computer Science   information   Neuroscience   Neural Networks  

摘要： This project kicked off in the fall of 2020. There are two parts of the title of this Research Topic -Special Issue. The first one evokes the issue raised by Turing ("Can machines think?", 1950), a question that we, the Editors, revisit reflecting our complementary multi-disciplinary backgrounds (Evolutionary Biology, GM; Evo-Devo, PM; and Computer Science, BM) and take it up again with a fresh start; this question made us realize how ripe the Brain-Computer analogy has become for a reassessment. The complexity of the subject needed the involvement of experts from the different fields that have been concerned with many related problems, namely Natural Sciences (here Biology and Physics), Mathematics, Psychology and Philosophy. Indeed, the Topic is certainly timely for, while this Issue was going to press, a number of publications have appeared that tackle these very issues both in Sciences (Reynolds, 2022;Yang and Lu, 2022) and Humanities (Kelty-Stephen et al., 2022). The second part of the title paraphrases a well-known aphorism in Statistics: "Essentially, all models are wrong, but some are useful" (George E.P. Box). This statement introduces the 'philosophical' part of this topic, viz. the semantic issue; in Turing's words: "Can machines think? This should begin with definitions of the meaning of the terms 'machine ' and 'think' " (1950). Indeed, both the Authors and the Editors of this Special Issue realized that a number of other concepts, crucial to evaluate the Brain-Computer relationships, were in need of an updated definition: machine (Bongard and Levin), computer (Richards and Lillicrap; Danchin and Fenton), metaphor and analogy (Matassi and Martinez).We started off by making a wishful list of relevant topics that would embrace a vast a spectrum of disciplines concerned. These were: Brain architecture, evolution and functioning; Neural Networks and Computational Neuroscience; Network Science (networ

关键词： 1 ( G ) <   2 ( G ) <   <   n ( G )   chemistry   computer science   etc   3   7-9   In recent years   several researchers studied   Adjacency spectrum   Laplacian spectrum   signless Laplacian spec-trum   cospectral graphs   Kirchhoff index   the number of spanning trees  

摘要： The splitting graph SP(G) of a graph G is the graph obtained from G by taking a new vertex u ' for each u is an element of V(G) and joining u ' to all vertices of G adjacent to u. For a connected regular graph G1 and an arbitrary regular graph G2, we determine the adjacency (respectively, Laplacian and signless Laplacian) spectra of two types of graph operations on G1 and G2 involving the SP-graph of G1. Moreover, applying these results we construct some non-regular simultaneous cospectral graphs for the adjacency, Laplacian and signless Laplacian matrices, and compute the Kirchhoff index and the number of spanning trees of the newly constructed graphs.

关键词： communication   narrative   hospitals   death education   self-care  

摘要： Background Based on the principles of Narrative Medicine, this study explored a narrative-based workshop for multi-level interdisciplinary clinicians who have EOL conversations. Methods Fifty-two clinicians participated in narrative-based interactive workshops. Participants engaged narrative in three forms: viewing narratives, writing/sharing narratives, and co-constructing narratives. Post workshop interviews were conducted and thematically analyzed. Results Five themes characterized how the workshop shaped learning and subsequent care experiences: (1) learning to enter/respond to the patient stories, (2) communicating across professions and disciplines, (3) practicing self-care. Additional themes emphasized (4) barriers to narrative learning and (5) obstacles to applying narrative to practice. Discussion Results highlight the function/utility of narrative forms such as the value of processing emotions via reflective writing, feeling vulnerable while sharing narratives, and appreciating colleagues' obstacles while observing patient-clinician simulations. Challenges associated with narrative such as writing anxiety and barriers to implementation such as time constraints are detailed to inform future initiatives.

关键词： SCOBY   Ethanol   Acinetobacter   Candida   Pichia   Gamma irradiation  

摘要： Bacterial cellulose has drawn the attention for its unique properties and applications including;medicine, pharmacy, food, agricultural, textile and electronics. The present study focused on the production of bacterial cellulose nanofibrils (BCNF) from black tea as cost effective alternative medium in addition to study the effect of gamma radiation on BCNF properties. A symbiotic culture of bacteria and yeast (SCOBY) were isolated from commercial Kombucha beverage and were identified as Acinetobacterlowffii and Candida krusei, respectively. The symbiotic culture was used for production of BCNF on Hestrin-Schramm (HS), black tea (BT) and modified BT media. BCNF was purified (0.5 N NaOH) and quantified by dry weight, yield and productivity determination. Characterization and effect of gamma radiation (5-25 kGy) on BCNF were studied using Scanning Electron Microscope (SEM), Fourier transform infrared (FTIR) and X-Ray Diffraction (XRD). The highest BCNF production was achieved using BT medium with 0.2% tea and 6.0% commercial sugar (with dry weight 4.77-4.61 g/l and productivity 68.14% and 65.85%, respectively). Supplementation of BT medium with 1% ethanol, 0.27% Na2HPO4 and 0.5% yeast extract individually, enhanced the BCNF production (7.85, 6.84 and 5.73 g/l), respectively. FTIR spectrum of BCNF from sugared water (SW), HS and BT showed similar structure with high purity. As a conclusion, gamma irradiation has no effect on the BCNF structure while showed different effects on its crystallinity index and size with the different doses. The changes in CrI were ranged between (17 and 23.5%), while the crystallinity size (Cs) was affected by gamma irradiation in a positive relationship where the crystalline size was decreased (33%) by exposure to 5 kGy then increased by increasing the dose of radiation reaching 25.7% at 25 kGy. SEM graphs showed the morphology of microbial culture and its symbiotic relationship in addition to the ultrafine structure of non-irradiated and ir