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Hepatitis B Surface Antigen and Hepatitis C Virus Antibodies among Drug Users in Burkina Faso
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作者 Sylvie Zida Kadari Cissé +13 位作者 Odette Ky-Zerbo Dinanibè Kambiré Serge Théophile Soubeiga Simon Tiendrebéogo Fatou Sissoko Issa Sory Célestine Ki-Toé Solange Dioma Djeneba Zorom Adama Ouédraogo Cedric Dimitri Axon Hien Mahamoudou Sanou Seni Kouanda Henri Gautier Ouédraogo 《Advances in Microbiology》 CAS 2024年第1期92-104,共13页
Introduction: The epidemiology of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among drug users (DUs) is little known in West Africa. The study aimed to assess the prevalence of hepatitis B and ... Introduction: The epidemiology of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among drug users (DUs) is little known in West Africa. The study aimed to assess the prevalence of hepatitis B and C viruses among drug users in Burkina Faso. Methodology: This was a cross-sectional biological and behavioral survey conducted between June and August 2022, among drug users in Ouagadougou and Bobo Dioulasso, the two main cities of Burkina Faso. A respondent-driven sampling (RDS) was used to recruit drug users. Hepatitis B surface antigen was determined using lateral flow rapid test kits and antibodies to hepatitis C virus in serum determined using an Enzyme-Linked Immunosorbent Assay. Data were entered and analyzed using Stata 17 software. Weighted binary logistic regression was used to identify the associated factors of hepatitis B and C infections and a p-value Results: A total of 323 drug users were recruited with 97.5% males. The mean age was 32.7 years old. The inhaled or smoked mode was the most used by drug users. The adjusted hepatitis B and hepatitis C prevalence among study participants were 11.1% and 2.3% respectively. The marital status (p = 0.001), and the nationality (p = 0.011) were significantly associated with hepatitis B infection. The type of drug used was not significantly associated with hepatitis B infection or hepatitis C infection. Conclusion: The prevalence of HBsAg and anti-HCV antibodies among DUs are comparable to those reported in the general population in Burkina Faso. This result suggests that the main routes of contamination by HBV and HCV among DUs are similar to those in the population, and could be explained by the low use of the injectable route by DUs in Burkina Faso. 展开更多
关键词 Drug users Hepatitis C Hepatitis B PREVALENCE Burkina Faso
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Evaluation of an Autonomous Vehicle User Interface for Sensory Impaired Users
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作者 Elena Angeleska Linda Lüchtrath Paolo Pretto 《Journal of Transportation Technologies》 2024年第4期570-589,共20页
Autonomous vehicles (AVs) hold immense promises in revolutionizing transportation, and their potential benefits extend to individuals with impairments, particularly those with vision and hearing impairments. However, ... Autonomous vehicles (AVs) hold immense promises in revolutionizing transportation, and their potential benefits extend to individuals with impairments, particularly those with vision and hearing impairments. However, the accommodation of these individuals in AVs requires developing advanced user interfaces. This paper describes an explorative study of a multimodal user interface for autonomous vehicles, specifically developed for passengers with sensory (vision and/or hearing) impairments. In a driving simulator, 32 volunteers with simulated sensory impairments, were exposed to multiple drives in an autonomous vehicle while freely interacting with standard and inclusive variants of the infotainment and navigation system interface. The two user interfaces differed in graphical layout and voice messages, which adopted inclusive design principles for the inclusive variant. Questionnaires and structured interviews were conducted to collect participants’ impressions. The data analysis reports positive user experiences, but also identifies technical challenges. Verified guidelines are provided for further development of inclusive user interface solutions. 展开更多
关键词 Autonomous Vehicles user Interface Inclusive Design Wizard of Oz Simulation
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Reform of the Irrigation Sector and Creation of Functional and Sustainable Irrigation Water Users Associations (AUEI) in Niger: Capitalization of the Experience of the Konni AHA
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作者 Saidou Abdoulkarimou Illou Mahamadou 《Agricultural Sciences》 2024年第2期209-229,共21页
During the 1980s, as part of a policy of liberalization, following budgetary cuts linked to the implementation of structural adjustment programs, management responsibilities for AHAs were transferred from ONAHA to coo... During the 1980s, as part of a policy of liberalization, following budgetary cuts linked to the implementation of structural adjustment programs, management responsibilities for AHAs were transferred from ONAHA to cooperatives concerned. Due to lack of financial resources, but also because of poor management, everywhere in Niger we are witnessing an accelerated deterioration of the irrigation infrastructure of hydro-agricultural developments. Institutional studies carried out on this situation led the State of Niger to initiate a reform of the governance of hydro-agricultural developments, by streng-thening the status of ONAHA, by creating an Association of Irrigation Water Users (AUEI) and by restructuring the old cooperatives. Indeed, this research aims to analyze the creation of functional and sustainable Irrigation Water User Associations (AUEI) in Niger in a context of reform of the irrigation sector, and based on the experience of the Konni AHA. It is based on a methodological approach which takes into account documentary research and the collection of data from 115 farmers, selected by reasoned choice and directly concerned by the management of the irrigated area. The data collected was analyzed and the results were analyzed using the systemic approach and the diagnostic process. The results show that the main mission of the AUEI is to ensure better management of water, hydraulic equipment and infrastructure on the hydro-agricultural developments of Konni. The creation of the Konni AUEI was possible thanks to massive support from the populations and authorities in the implementation process. After its establishment, the AUEI experienced a certain lethargy for some time due to the rehabilitation work of the AHA but currently it is functional and operational in terms of associative life and governance. Thus, the constraints linked to the legal system, the delay in the completion of the work, the uncertainties of access to irrigation water but also the problems linked to the change in mentality of certain ONAHA agents constitute the challenges that must be resolved in the short term for the operationalization of the Konni AUEI. 展开更多
关键词 Konni (Niger) Hydro-Agricultural Developments Association of Irrigation Water users GOVERNANCE
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Design Method for Optimizing the Interactive Interface of Live Broadcasting Platform for the Elderly Users
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作者 WEI Bi-ze FAN Wei DUAN Ying-ke 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期167-178,共12页
In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interact... In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interaction design mode used is still mainly based on the interaction mode for young groups,and is not designed for elderly users.Therefore,a design method for optimizing the interaction interface of live broadcasting platform for elderly users was proposed in this study.Firstly,the case study method and Delphi expert survey method were used to determine the design needs of elderly users and the design mode was analysed.Secondly,the orthogonal design principle was used to design a test sample of the interactive interface of live broadcasting platform applicable for the elderly users,and then a user evaluation system was established to calculate the weights of the design elements using hierarchical analysis,and then the predictive relationship between the design mode of the interactive interface of live broadcasting platform and the elderly users was established by Quantitative Theory I.Finally,Genetic Algorithm was applied to generate the optimized design scheme.The results showed that the design method based on the Genetic Algorithm and the combination of Quantitative Theory can scientifically and effectively optimize the design of the interactive interface of the live broadcasting platform for the elderly users,and improve the experience of the elderly users. 展开更多
关键词 Live broadcasting platform Interaction design Elderly users Genetic Algorithm Quantitative Theory I
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Study on the Alignment Between Talent Training Directions and Employment Market Demands in the Landscape Architecture Industry
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作者 Fengyi Xu Yang Su 《Journal of Contemporary Educational Research》 2024年第5期80-84,共5页
Currently,talent training in Chinese universities for landscape architecture is mainly divided into three directions:“landscape planning and design,”“landscape construction management,”and“landscape plant plantin... Currently,talent training in Chinese universities for landscape architecture is mainly divided into three directions:“landscape planning and design,”“landscape construction management,”and“landscape plant planting and maintenance.”However,with the background of the slowing urbanization process and the widespread demand for composite talents in society,it remains to be verified whether the traditional three major talent training directions in landscape architecture align with the job demands in the current construction market.Based on a survey and analysis of over 300 industry practitioners,this study found a clear trend of merging the three major employment directions into“landscape design and construction”and“landscape plant planting and maintenance.”This presents new requirements and directions for the skill training of landscape architecture majors in universities and provides insights into the alignment between talent training and employment demands in other industries. 展开更多
关键词 Landscape architecture profession Professional skills Employer demands Integration of industry and education
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Demands and influencing factors of digital transition care service in discharged older patients:a cross-sectional study
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作者 Cheng-Rui Zhang Zhu Zhu +1 位作者 Ying Xing Wei Luan 《Nursing Communications》 2024年第25期1-13,共13页
Objective:To identify the group classification of discharged older adults’digital transition care demands and analyze its influencing factors.Methods:From July to August 2022,we used stratified random sampling to rec... Objective:To identify the group classification of discharged older adults’digital transition care demands and analyze its influencing factors.Methods:From July to August 2022,we used stratified random sampling to recruit older patients who were discharged between July 2021 and July 2022 from tertiary hospitals in Shanghai.We used latent profile analysis to classify the older patients into distinct groups based on their service demands:low,medium,and high.We use multiple logistic regression to explore the factors influencing the different demand levels.Results:The degree of discharged older patients’demand was classified as low(Category 1(C1),34.2%),medium(Category 2(C2),49.5%),high-demand levels(Category 3(C3),16.3%).Compared to those have C2,older adults in C1 are more likely to be male(Odds Ratio(OR)=2.81,P=0.02),have 2 chronic diseases(OR=3.91,P=0.03),and are less likely to be junior high and below(OR=0.09,P=0.00),hospitalized for 1–2 times in the past year(1 times:OR=0.19,P=0.07;2 times:OR=0.14,P=0.02),living with children(OR=0.32,P=0.05),have less insurance(OR=0.48,P=0.03),less understanding of digital transitional care(OR=0.47,P=0.01),have less eHealth literacy(OR=0.80,P=0.00),have less degree of importance attributed by family(OR=0.52,P=0.03);Compared to those have medium demand level,older adults in high demand level are more likely to have self and spouse as primary income(self:OR=26.35,P=0.00;spouse:OR=24.06,P=0.02),walking to the nearest health facility(self:6.74,P=0.03),have higher eHealth literacy(OR=1.88,P=0.00),degree of importance within the family(OR=5.19,P=0.01),higher self’s influence on medical decisions-making(OR=5.69.P=0.01).They are less likely to be in 60–79 years group(OR=0.00–0.37,P=0.00–0.03),Household Annual Income<5,000 CNY(OR=0.05,P=0.02).Conclusion:Digital transitional care demands of discharged older patients can be divided into three categories.Constructing a digital transitional care service system that aligns with the demands of discharged older patients is essential.Communication,care plan development,and follow-up are the most fundamental services.Additionally,it is essential to understand the characteristics of high-demand populations to provide tailored services and identify vulnerable populations from health and social perspectives to offer cost-effective transitional care services. 展开更多
关键词 transitional care geriatric health services medical informatics applications health services needs and demand
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The Intersection of Privacy by Design and Behavioral Economics: Nudging Users towards Privacy-Friendly Choices
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作者 Vivek Kumar Agarwal 《Journal of Information Security》 2024年第4期557-563,共7页
This paper conducts a comprehensive review of existing research on Privacy by Design (PbD) and behavioral economics, explores the intersection of Privacy by Design (PbD) and behavioral economics, and how designers can... This paper conducts a comprehensive review of existing research on Privacy by Design (PbD) and behavioral economics, explores the intersection of Privacy by Design (PbD) and behavioral economics, and how designers can leverage “nudges” to encourage users towards privacy-friendly choices. We analyze the limitations of rational choice in the context of privacy decision-making and identify key opportunities for integrating behavioral economics into PbD. We propose a user-centered design framework for integrating behavioral economics into PbD, which includes strategies for simplifying complex choices, making privacy visible, providing feedback and control, and testing and iterating. Our analysis highlights the need for a more nuanced understanding of user behavior and decision-making in the context of privacy, and demonstrates the potential of behavioral economics to inform the design of more effective PbD solutions. 展开更多
关键词 Privacy by Design Behavioral Economics Nudges user-Centric Design Data Protection Cognitive Biases HEURISTICS
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Enable Excel-Based Basic Cybersecurity Features for End Users by Using Python-Excel Integration
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作者 Mohamed Breik Osama Magdy +2 位作者 Essam Amin Tarek Aly Mervat Gheith 《Journal of Software Engineering and Applications》 2024年第6期522-529,共8页
In the digital age, the global character of the Internet has significantly improved our daily lives by providing access to large amounts of knowledge and allowing for seamless connections. However, this enormously int... In the digital age, the global character of the Internet has significantly improved our daily lives by providing access to large amounts of knowledge and allowing for seamless connections. However, this enormously interconnected world is not without its risks. Malicious URLs are a powerful menace, masquerading as legitimate links while holding the intent to hack computer systems or steal sensitive personal information. As the sophistication and frequency of cyberattacks increase, identifying bad URLs has emerged as a critical aspect of cybersecurity. This study presents a new approach that enables the average end-user to check URL safety using Microsoft Excel. Using the powerful VirusTotal API for URL inspections, this study creates an Excel add-in that integrates Python and Excel to deliver a seamless, user-friendly interface. Furthermore, the study improves Excel’s capabilities by allowing users to encrypt and decrypt text communications directly in the spreadsheet. Users may easily encrypt their conversations by simply typing a key and the required text into predefined cells, enhancing their personal cybersecurity with a layer of cryptographic secrecy. This strategy democratizes access to advanced cybersecurity solutions, making attentive digital integrity a feature rather than a daunting burden. 展开更多
关键词 Python End-user Approach EXCEL Excel Add-In CYBERSECURITY URL Check API Virustotal API Encryption Decryption Vigenère Cipher Python-Excel Integration
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RESEARCH ON MUNICIPAL WATER DEMANDS FORECAST 被引量:3
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作者 赵新华 田一梅 陈春芳 《Transactions of Tianjin University》 EI CAS 2001年第1期21-25,共5页
Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand du... Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand during holidays and under unexpected events is also presented.Meanwhile,a computer software is developed.Through actual application,this method performs well and has high accuracy,so it can be applied to the daily operation of a water distribution system and lay a foundation for on-line optimal operation. 展开更多
关键词 water supply short-term demand forecast time-series analysis
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Survey of HIV Infection among Injection Drug Users in Guangdong, China 被引量:1
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作者 林鹏 刘勇鹰 +5 位作者 王晔 付笑冰 许锐恒 万卓越 颜瑾 赵茜茜 《Chinese Journal of Sexually Transmitted Infections》 2005年第1期5-9,共5页
Objective: To understand the prevalence and behavioral risk factors of HIV infection among injection drug users in the Pearl River Delta Region (PRDR) of Guangdong province, and to provide evidence for establishing... Objective: To understand the prevalence and behavioral risk factors of HIV infection among injection drug users in the Pearl River Delta Region (PRDR) of Guangdong province, and to provide evidence for establishing effective intervention strategies. Methods: Face to face interviews were conducted and serum samples from injection drug users from detoxification centers and the community were collected for HIV screening. Results: 655 drug users were recruited and interviewed. The HIV seropositive rate was 29.0%. 99.5 % of subjects were injection drug users (IDUs), of whom,75.4% reported sharing injection equipment. Conclusion: HIV prevalence among injection drug users is high in the PRDR of Guangdong. Injection drug use is the principal behavioral risk factor for HIV transmission. Pragmatic harm reduction programs should be implemented to prevent the spread of HIV infection. 展开更多
关键词 HIV/AIDS risk behavior drug users
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Sensitivity analysis for stochastic user equilibrium with elastic demand assignment model
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作者 王建 吴鼎新 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期363-367,共5页
This paper puts forward a rigorous approach for a sensitivity analysis of stochastic user equilibrium with the elastic demand (SUEED) model. First, proof is given for the existence of derivatives of output variables... This paper puts forward a rigorous approach for a sensitivity analysis of stochastic user equilibrium with the elastic demand (SUEED) model. First, proof is given for the existence of derivatives of output variables with respect to the perturbation parameters for the SUEED model. Then by taking advantage of the gradient-based method for sensitivity analysis of a general nonlinear program, detailed formulae are developed for calculating the derivatives of designed variables with respect to perturbation parameters at the equilibrium state of the SUEED model. This method is not only applicable for a sensitivity analysis of the logit-type SUEED problem, but also for the probit-type SUEED problem. The application of the proposed method in a numerical example shows that the proposed method can be used to approximate the equilibrium link flow solutions for both logit-type SUEED and probit-type SUEED problems when small perturbations are introduced in the input parameters. 展开更多
关键词 network modeling stochastic user equilibrium elastic demand sensitivity analysis first-order approximation
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Study on Guidance of Users’Point of View to Construction of Urban Park in China——Inspiration by "Reflection on Urban Park:Public Space and Multi-culture"
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作者 王璐艳 刘克成 《Journal of Landscape Research》 2010年第8期14-16,20,共4页
New idea studying urban parks was opened up by "Reflection on Urban Park:Public Space and Multi-culture". By introducing anthropology into planning and design methodology of urban public space, it provided a... New idea studying urban parks was opened up by "Reflection on Urban Park:Public Space and Multi-culture". By introducing anthropology into planning and design methodology of urban public space, it provided a new research method for the planning of urban park in our country. Through introduction and assessment of the book, existing problems and suggestions of the construction of our urban parks were proposed. In the perspective of urban parks' users, by the method of ethnology and anthropology, cultural diversity of urban public space would be investigated, paying attention to the usage behavior and different cultural characteristics, thinking about how to respect ecology and environmental construction of parks and coordinate the relation between culture and ecology while cultural diversity was respected. What should be considered in the construction of urban parks was not only culture but also ecological environment protection when culture was respected and citizens' interests during environment construction. These were also the fundamental problems needed to be considered and solved in parks' planning, construction and operation. 展开更多
关键词 Urban PARK users Planning Culture ECOLOGY
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Research of Informatization Demands of New Countryside in Poyang Lake Ecological Economic Zone and Related Countermeasures
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作者 戴天放 陈智辉 《Agricultural Science & Technology》 CAS 2012年第12期2675-2680,共6页
[Objective] The aim was to survey and analyze informatization demand in new countryside in Poyang Lake Ecological Economic Zone and to propose counter- measures, [Method] A questionnaire was made among farmers on info... [Objective] The aim was to survey and analyze informatization demand in new countryside in Poyang Lake Ecological Economic Zone and to propose counter- measures, [Method] A questionnaire was made among farmers on informatization de- mands in different regions in Poyang Lake Ecological Economic Zone and the re- sults were analyzed to propose countermeasures promoting informatization. [Result] With strengthening of information awareness, information demands in rural areas in Poyang Lake Ecological Economic Zone change as follows: Information demand car- rier changes from traditional media to modern media; demand on information content changes from one-way to diversified one; demand of information service changes from one-way transmission to interaction and exchange. However, some problems still exist in informatization process, such as poor infrastructure, dispersed information resources, higher information expense and shortage of information-based talents. Hence, the countermeasures were proposed, as follows: Rational security systems should be established; financing should be as diversified as possible; informatization infrastructure should be reinforced; agricultural economic information and informatiza- tion service system should be established. [Conclusion] The research lays foundation for construction of informatization in new countryside in Poyang Lake Ecological Economic Zone. 展开更多
关键词 Poyang Lake Ecological Economic Zone Informatization demand by farmers SURVEY COUNTERMEASURES
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Proxy-Users系统收入分配的Stackelberg模型及解的存在性
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作者 韩海山 斯琴 《内蒙古民族大学学报(自然科学版)》 2005年第2期121-124,共4页
用对策论的Stackelberg平衡理论研究了Proxy-Users系统中Proxy和Users之间分配收入问题.对Proxy和Users的地位不平等且Proxy不能按到达率提供服务的情况,建立了收入分配的Stackelberg策略模型,得到了一个双层规划模型,并证明了模型的解... 用对策论的Stackelberg平衡理论研究了Proxy-Users系统中Proxy和Users之间分配收入问题.对Proxy和Users的地位不平等且Proxy不能按到达率提供服务的情况,建立了收入分配的Stackelberg策略模型,得到了一个双层规划模型,并证明了模型的解的存在性. 展开更多
关键词 对策 Stackelberg策略 Proxy—users通信系统 双层规划 收入分配
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Challenges and Demands for College English Teachers Raised by Training All-round Qualified Persons
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作者 江庆心 《Sino-US English Teaching》 2006年第4期1-4,共4页
The latest issue of College English Curriculum Requirements has posed challenges and demands for teachers in terms of linguistic competence, academic knowledge, language skills, professional morality, emotional and at... The latest issue of College English Curriculum Requirements has posed challenges and demands for teachers in terms of linguistic competence, academic knowledge, language skills, professional morality, emotional and attitudinal qualifications, etc., which requires teachers to embrace and handle with active and open-minded responses. Hence, teachers ought to strive to develop and improve their own overall qualifications in collaboration with the long-term development of the subject and of the national higher education, with the need of qualified persons demanded by social development and the students' learning. Teachers also ought to form a notion of scientific development by keeping pace with the time, so as to discern the trend of subject development, to form appropriate judgments concerning the social development and to properly regulate their own development. 展开更多
关键词 all-round qualified persons teaching requirements teachers' overall qualifications CHALLENGES demands
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Server-Proxy-Users系统收入分配的对策论模型及解的存在性
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作者 韩海山 陈荣江 斯琴 《工程数学学报》 CSCD 北大核心 2005年第8期63-66,共4页
用对策论研究了Server-Proxies-Users系统中Server、Proxies和Users之间的收入分配问题,建立了收入分配的对策论模型,得到了三层规划模型。根据三层规划模型的特殊性,把它分解成两个双层规划模型,同时证明了模型的解的存在性。
关键词 对策论 Server-Proxies-users系统 三层规划 收入分配
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Link Demands对.NET Framework分布式系统安全性的影响
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作者 杜树杰 林晓彤 刘士才 《计算机工程与应用》 CSCD 北大核心 2004年第8期143-147,共5页
客观地讲,.NET安全体系是采用全新的模式建立的,更多地考虑了基于.NET的应用系统在安全性和执行效率上的统一,这一点是可以理解的。它提出了基于WEB的分布式应用系统在安全核心技术上新的设计思想。影响.NETFramework应用系统安全性的... 客观地讲,.NET安全体系是采用全新的模式建立的,更多地考虑了基于.NET的应用系统在安全性和执行效率上的统一,这一点是可以理解的。它提出了基于WEB的分布式应用系统在安全核心技术上新的设计思想。影响.NETFramework应用系统安全性的因素有很多,其中由链接请求(Linkdemands)引起的影响系统安全性的潜在错误相当多。文章分析了Linkdemands可能带来的系统安全性隐患,并就此提出了一些建议。 展开更多
关键词 链接请求 .NET Framework JIT 堆栈遍历 CLR 中间语言
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Server-Agents-Users通信系统的Stackelberg模型
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作者 韩海山 夏尊铨 《大连理工大学学报》 EI CAS CSCD 北大核心 2004年第3期334-336,共3页
在多媒体通信系统中引入代理服务器,使其成为Server-Agents-Users系统,并用对策论的Stackelberg理论研究该系统.针对Server、Agents和Users地位不平等的情况,建立了该系统的Stackelberg策略模型,得到一个三层规划模型.
关键词 Server-Agents-users通信系统 对策论 Slackelberg策略 三层规划模型 多媒体通信 代理服务器 服务质量
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Time-variant fragility analysis of the bridge system considering time-varying dependence among typical component seismic demands 被引量:6
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作者 Song Shuai Qian Yongjiu +2 位作者 Liu Jing Xie Xiaorui Wu Gang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第2期363-377,共15页
This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Bas... This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Based on material deterioration mechanisms and incremental dynamic analysis, the time-evolving seismic demands of components were obtained in the form of marginal probability distributions. The time-varying dependences among bridge components were then captured with the best fitting copula function, which was selected from the commonly used copula classes by the empirical distribution based analysis method. The system time-variant fragility curves at different damage states were developed and the effects of time-varying dependences among components on the bridge system fragility were investigated. The results indicate the time-varying dependence among components significantly affects the time-variant fragility of the bridge system. The copula technique captures the nonlinear dependence among component seismic demands accurately and easily by separating the marginal distributions and the dependence among them. 展开更多
关键词 system FRAGILITY CHLORIDE corrosion TIME-VARYING DEPENDENCE COPULA function probabilistic seismic demand
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Ductility demands on buckling-restrained braced frames under earthquake loading 被引量:11
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作者 Larry A.Fahnestock Richard Sause +1 位作者 James M.Ricles Le-Wu Lu 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期255-268,共14页
Accurate estimates of ductility demands on buckling-restrained braced frames(BRBFs)are crucial to performance-based design of BRBFs.An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS ... Accurate estimates of ductility demands on buckling-restrained braced frames(BRBFs)are crucial to performance-based design of BRBFs.An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS Center,Lehigh University to prepare for an upcoming experimental program.The analysis program DRAIN-2DX was used to model a one-bay,four-story prototype BRBF including material and geometric nonlinearities.The buckling- restrained brace(BRB)model incorporates both isotropic and kinematic hardening.Nonlinear static pushover and time- history analyses were performed on the prototype BRBF.Performance objectives for the BRBs were defined and used to evaluate the time-history analysis results.Particular emphasis was placed on global ductility demands and ductility demands on the BRBs.These demands were compared with anticipated ductility capacities.The analysis results,along with results from similar previous studies,are used to evaluate the BRBF design provisions that have been recommended for codification in the United States.The results show that BRB maximum ductility demands can be as high as 20 to 25.These demands significantly exceed those anticipated by the BRBF recommended provisions.Results from the static pushover and time- history analyses are used to demonstrate why the ductility demands exceed those anticipated by the recommended provisions. The BRB qualification testing protocol contained in the BRBF recommended provisions is shown to be inadequate because it requires only a maximum ductility demand of at most 7.5.Modifications to the testing protocol are recommended. 展开更多
关键词 BUILDINGS buckling-restrained braced frames buckling-restrained braces structural response seismic response ductility demand seismic codes and standards
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