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A Dimensional Reduction Approach Based on Essential Constraints in Linear Programming

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American Journal of Operations Research 2024年第1期14卷 1-31页

作者： Eirini I. Nikolopoulou george s. Androulakis Department of Mathematics University of Patras Patras Greece Department of Business Administration University of Patras Patras Greece

This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted average and the cosine simplex algorithm. The first approach identifies binding constraints by using the weighted average of each constraint, whereas the second algorithm is based on the cosine similarity between the vector of the objective function and the constraints. These two approaches are complementary, and when used together, they locate the essential subset of initial constraints required for solving medium and large-scale linear programming problems. After reducing the dimension of the linear programming problem using the subset of the essential constraints, the solution method can be chosen from any suitable method for linear programming. The proposed approach was applied to a set of well-known benchmarks as well as more than 2000 random medium and large-scale linear programming problems. The results are promising, indicating that the new approach contributes to the reduction of both the size of the problems and the total number of iterations required. A tree-based classification model also confirmed the need for combining the two approaches. A detailed numerical example, the general numerical results, and the statistical analysis for the decision tree procedure are presented.

关键词： Linear Programming Binding Constraints Dimension Reduction Cosine similarity Decision Analysis Decision Trees

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《全球科技创新中心:理论与实践》评介

世界地理研究 2024年第7期33卷 184-188页

作者：林初昇香港大学地理系中国香港999077

如果要选择一个词来表达当今中国各级决策者的雄心抱负,可能没有比“创新”更合适的了。“创新”作为中国目前发展的一项新使命和新愿景,深深地激励着全国上下各级的决策者。长期以来,中国很多地方政府沉迷于将城市建设成为各种大大小... 详细信息

如果要选择一个词来表达当今中国各级决策者的雄心抱负,可能没有比“创新”更合适的了。“创新”作为中国目前发展的一项新使命和新愿景,深深地激励着全国上下各级的决策者。长期以来,中国很多地方政府沉迷于将城市建设成为各种大大小小的“世界城市”。然而近十年来,建设“全球科技创新中心”迅速风靡神州大地,成为国家和地方发展议程中的首要任务。虽然我国各级领导的规划与决策正经历前所未有的“创新转向”,但是我相信极少决策者有足够信心宣称自己知道“全球科技创新中心”的本质和态势。

关键词：全球科技创新中心理论与实践发展议程规划与决策决策者新愿景首要任务

Foreword from Editor-in-Chief george ***--China’s Outreach to the World:Public Health Goes Global

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China CDC weekly 2019年第1期1卷 1-2页

作者： george F.Gao China CDC Weekly Chinese Center for Disease Control and Prevention

China CDC Weekly is a national public health bulletin published by the Chinese Center for Disease Control and Prevention(China CDC).It will serve as the primary communications channel of China CDC for disseminating timely,reliable,authoritative,accurate,objective and useful public health information as well as recommendations to health professionals and the *** CDC Weekly is indexed and archived as a scientific journal,and its contents can therefore be searched and referenced.

关键词： journal bulletin timely

Urban China in Transformation:Hybrid Economy,Juxtaposed space,and New Testing Ground for Geographical Enquiries

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Chinese Geographical science 2011年第1期21卷 1-16页

作者： george C s LIN Department of Geography University of Hong Kong

History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of manufacturing is no longer confined to the Global North. This paper provides a periodical assessment of the current status of China's urban transformation in the global context of a shifting emphasis of industrialization and urbaniza-tion. China's phenomenal urban transformation deserves a special attention not only because of its unparalleled scale and speed but also because of its distinct trajectory of growth that does not conform to normal theoretical ex-pectations. The results of assessment revealed an urban economy with remarkable hybridity, a society that is in-creasingly stratified, polarized, and segregated, and a juxtaposed urban space undergoing restless and pervasive transformation. A decentering world should entail a decentering knowledge production. A critical reflection upon the Chinese patterns and processes of urban transformation has identified 4 main issues with great potentials for inno-vative knowledge production, namely: 1) privatization and economic development; 2) state, society, and space; 3) urbanization of capital, labor, and land; and 4) the environment and Chinese political ecology. The paper closes with the remark that a rapidly transforming urban China has presented itself as a fertile and resourceful testing ground for critical and innovative geographic enquiries.

关键词：中国模式城市转型城市经济城市空间试验场查询地理城市居住区

Improved Feistel-based ciphers for wireless sensor network security

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2008年第8期9卷 1111-1117页

作者： Tamara PAZYNYUK george s. OREKU Department of Computer science and Engineering Harbin Institute of TechnologyHarbin 150006 China

Wireless sensor networks (WsNs) are exposed to a variety of attacks. The quality and complexity of attacks are rising day by day. The proposed work aims at showing how the complexity of modern attacks is growing accordingly, leading to a similar rise in methods of resistance. Limitations in computational and battery power in sensor nodes are constraints on the diversity of security mechanisms. We must apply only suitable mechanisms to WsN where our approach was motivated by the application of an improved Feistel scheme. The modified accelerated-cipher design uses data-dependent permutations, and can be used for fast hardware, firmware, software and WsN encryption systems. The approach presented showed that ciphers using this approach are less likely to suffer intrusion of differential cryptanalysis than currently used popular WsN ciphers like DEs, Camellia and so on.

关键词：计算机网络安全技术无线电传感器

Athletes with mild post-COVID-19 symptoms experience increased respiratory and metabolic demands:А cross-sectional study

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sports Medicine and Health science 2023年第2期5卷 106-111页

作者： Vasileios T.stavrou Astara Kyriaki george D.Vavougios Ioannis G.Fatouros george s.Metsios Konstantinos Kalabakas Dimitrios Karagiannis Zoe Daniil Konstantinos I.Gourgoulianis george Вasdekis Laboratory of Cardio-Pulmonary Testing and Pulmonary Rehabilitation Respiratory Medicine DepartmentFaculty of MedicineUniversity of ThessalyLarissaGreece The Medical Project PreventionEvaluation and Recovery CenterLarissaGreece Department of Neurology 417 Army Equity Fund Hospital(NIMTS)AthensGreece Department of Neurology Faculty of MedicineUniversity of CyprusLefkosiaCyprus school of Physical Education and sport sciences University of ThessalyTrikalaGreece Department of Nutrition and Dietetics University of ThessalyTrikalaGreece

Coronavirus Disease 2019(COVID-19)has significantly affected different physiological systems,with a potentially profound effect on athletic ***,to date,such an effect has been neither addressed nor ***,the aim of this study was to investigate fitness indicators,along with the respiratory and metabolic profile,in post-COVID-19 *** male soccer players,were divided into two groups:non-hospitalized COVID-19(n=20,Age:[25.2±4.1]years,Body surface Area[BsA]:[1.9±0.2]m^(2),body fat:11.8%±3.4%)versus[vs]healthy(n=20,Age:[25.1±4.4]years,BsA:[2.0±0.3]m^(2),body fat:10.8%±4.5%).For each athlete,prior to cardiopulmonary exercise testing(CPET),body composition,spirometry,and lactate blood levels,were *** between groups were assessed with the independent samples t-test(pseveral differences were detected between the two groups:ventilation(:Resting:[14.7±3.1]L·min^(−1)vs.[11.5±2.6]L·min^(−1),p=0.001;Maximal Effort:[137.1±15.5]L·min^(−1)vs.[109.1±18.4]L·min^(−1),psting:7.9%±1.8%vs.5.7%±1.7%,ps.63.1%±9.0%,p=0.002),ratioVE/BsA(Resting:7.9%±2.0%vs.5.9%±1.4%,p=0.001;Maximal Effort:73.7%±11.1%vs.66.2%±9.2%,p=0.026),heart rate(Maximal Effort:[191.6±7.8]bpm vs.[196.6±8.6]bpm,p=0.041),and lactate acid(Resting:[1.8±0.8]mmol·L^(−1)vs.[0.9±0.1]mmol·L^(−1),ps.[9.8±1.2]mmol·L^(−1),p=0.009),during *** significant differences were identified regarding maximal oxygen uptake([55.7±4.4]ml·min^(−1)·kg−1 vs.[55.4±4.6]ml·min^(−1)·kg−1,p=0.831).Our findings demonstrate a pattern of compromised respiratory function in post-COVID-19 athletes characterized by increased respiratory work at both rest and maximum effort as well as hyperventilation during exercise,which may explain the reported increased metabolic needs.

关键词： Cardiopulmonary exercise testing Infected with COVID-19 Respiratory work

Predicting individuals’vulnerability to social engineering in social networks

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Cybersecurity 2018年第1期1卷 710-728页

作者： samar Muslah Albladi george R.s.Weir College of Computer science and Engineering University of JeddahJeddahKingdom of Saudi Arabia Department of Computer and Information sciences University of StrathclydeGlasgowUK

The popularity of social networking sites has attracted billions of users to engage and share their information on these *** vast amount of circulating data and information expose these networks to several security *** engineering is one of the most common types of threat that may face social network *** and increasing users’awareness of such threats is essential for maintaining continuous and safe use of social networking *** the most vulnerable users in order to target them for these training programs is desirable for increasing the effectiveness of such *** studies have investigated the effect of individuals’characteristics on predicting their vulnerability to social engineering in the context of social *** address this gap,the present study developed a novel model to predict user vulnerability based on several perspectives of user *** proposed model includes interactions between different social network-oriented factors such as level of involvement in the network,motivation to use the network,and competence in dealing with threats on the *** results of this research indicate that most of the considered user characteristics are factors that influence user vulnerability either directly or ***,the present study provides evidence that individuals’characteristics can identify vulnerable users so that these risks can be considered when designing training and awareness programs.

关键词： Deception Information security Phishing social engineering social network Vulnerability

Dos detections based on association rules and frequent itemsets

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Journal of Harbin Institute of Technology(New series) 2008年第2期15卷 283-289页

作者： george s Oreku Fredrick JMtenzi 李建中 Dept.of Computer science and Engineering Harbin Institute of Technology school of Computing Dublin Institute of Technology

To detect the Dos in networks by applying association rules mining techniques, we propose that association rules and frequent itemsets can be employed to find Dos pattern in packet streams which describe traffic and user behaviors. The method extracts information from the log analysis of submitted packets using the algorithm which depends on the definition of the intrusion. Large itemsets were extracted to represent the super facts to build the association analysis for the intrusion. Network data files were analysed for experiments. The analysis and experimental results are encouraging with better performance as packet frequency number increases.

关键词：自动控制技术资料数据采矿技术信息包

HARNEssING ECOLOGICAL PRINCIPLEs AND PHYsIOLOGIC MECHANIsMs IN DIVERsIFYING AGRICULTURAL sYsTEMs FOR sUsTAINABILITY:EXPERIENCE FROM sTUDIEs DEPLOYING NATUR-EBAsED sOLUTIONs IN sCOTLAND

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Frontiers of Agricultural science and Engineering 2022年第2期9卷 214-237页

作者： Timothy s.george Cathy HAWEs Tracy A.VALENTINE Alison J.KARLEY Pietro P.M.IANNETTA Robin W.BROOKER Ecological sciences Department The James Hutton InstituteInvergowrieDundeeDD25DAUK

To achieve the triple challenge of food security,reversing biodiversity declines plus mitigating and adapting to climate change,there is a drive to embed ecological principles into agricultural,value-chain practices and *** diversifying cropping systems at several scales there is potential to decrease reliance on inputs,provide resilience to abiotic and biotic stress,enhance plant,microbe and animal biodiversity,and mitigate against climate *** this review we highlight the research performed in scotland over the past 5 years into the impact of the use of ecological principles in agriculture on sustainability,resilience and provision of ecosystem *** demonstrate that diversification of the system can enhance ecosystem *** and plant management interventions,including nature-based solutions,can also enhance soil quality and utilization of legacy ***,this is facilitated by greater reliance on soil biological processes and trophic *** highlight the example of intercropping with legumes to deliver sustainability through ecological principles and use legumes as an exemplar of the *** conclude that there are many effective interventions that can be made to deliver resilient,sustainable,and diverse agroecosystems for crop and food production,and these may be applicable in any agroecosystem.

关键词： diversification ecological principles legumes plant management soil management soil ecosystem services