低温逆境已成为限制全球小麦稳产丰产与优质的主要农业气象灾害之一。为客观全面地了解全球小麦低温逆境领域的研究现状和发展趋势,基于Web of Science核心数据库中2000-2020年发表的以“小麦”和“低温”为研究主题的相关文献为数据源...低温逆境已成为限制全球小麦稳产丰产与优质的主要农业气象灾害之一。为客观全面地了解全球小麦低温逆境领域的研究现状和发展趋势,基于Web of Science核心数据库中2000-2020年发表的以“小麦”和“低温”为研究主题的相关文献为数据源,利用CiteSpace可视化分析软件对检索到与主题密切相关的475篇文献从发文数量、发文国家、发文作者、研究机构、研究热点等方面进行统计分析。结果表明:自2000年以来,小麦低温逆境领域年发文数量总体呈波动上升趋势;以中国、美国和加拿大等国家为代表的农业大国均致力于该领域的研究;美国学者Skin⁃ner是该领域发文量最多的作者,与其他学者合作密切的有李向楠和Fowler;该领域文献多发表于《Molecular Genetics and Genomics》和《Annual Review of Plant Biology》等优质期刊上;俄罗斯科学院是该领域发文量最多的科研机构;耐低温小麦新品种培育、耐寒分子生物学研究以及提高小麦产质量等方面成为该领域的研究热点。展开更多
In recent years, web technology carried on growing and at same time, the number of internet users increased significantly in number. Today, a Web server is capable of processing millions of requests per day, but durin...In recent years, web technology carried on growing and at same time, the number of internet users increased significantly in number. Today, a Web server is capable of processing millions of requests per day, but during the peak period may collapse and becomes critical causing unavailability of the services offered by the servers. That is why Web server performance is a topic of great interest to many researchers. In this paper, we evaluate experimentally the impact of JSP and PHP dynamic content technology: JSP and PHP with access to a database of performance data of Apache Web server. Using the “ApacheBench” performance measurement tool, the approach is to compare the performances of four different configurations of a Web server, such as: Apache Web server implementing JSP technology with access to PostgreSQL database, Apache using PHP technology with the PostgreSQL as database, Apache Web server using the JSP technology with access to MySQL database, finally Apache and PHP with DBMS MySQL. At the end of this article, we also present a Simulink model of Web server performance based on the simple M/M/1 queue. During the modeling, the MATLAB software was used.展开更多
Exponential increase in the quantity of user generated content in websites and social networks have resulted in the emergence of web intelligence approaches.Several natural language processing(NLP)tools are commonly u...Exponential increase in the quantity of user generated content in websites and social networks have resulted in the emergence of web intelligence approaches.Several natural language processing(NLP)tools are commonly used to examine the large quantity of data generated online.Particularly,sentiment analysis(SA)is an effective way of classifying the data into different classes of user opinions or sentiments.The latest advances in machine learning(ML)and deep learning(DL)approaches offer an intelligent way of analyzing sentiments.In this view,this study introduces a web intelligence with enhanced sunflower optimization based deep learning model for sentiment analysis(WIESFO-DLSA)technique.The major intention of the WIESFO-DLSA technique is to identify the expressions or sentiments that exist in the social networking data.The WIESFO-DLSA technique initially performs pre-processing and word2vec feature extraction processes to generate a meaningful set of features.At the same time,bidirectional long short term memory(BiLSTM)model is applied for classification of sentiments into different class labels.Moreover,an enhanced sunflower optimization(ESFO)algorithm is exploited to optimally adjust the hyperparameters of the BiLSTM model.A wide range of simulation analyses is performed to report the better outcomes of the WISFO-DLSA technique and the experimental outcomes ensured its promising performance under several measures.展开更多
Objective:With the development of Wendan decoction(WDD)and more literature on the research of WDD,we aimed to present an insight into WDD research using bibliometric analysis.Methods:We retrieved data from the Web of ...Objective:With the development of Wendan decoction(WDD)and more literature on the research of WDD,we aimed to present an insight into WDD research using bibliometric analysis.Methods:We retrieved data from the Web of Science database from 2008 to 2022.Publication trends were examined using data from journals,authors,institutions,international collaborations,citations,and keywords from the online analytical platform Bibliometric(http://bibliometric.com).Results:Over the years,an increase in the use of keywords,including depression,insomnia,Alzheimer’s disease,schizophrenia,hippocampus,and insomnia,was observed.The outcomes of the analysis revealed that topics related to WDD have become increasingly prevalent in the last five years,and the internationally recognized application of WDD is mainly neuropsychiatric diseases.Conclusion:We exhibited WDD research progress by identifying and evaluating WDD-focused articles.Our analysis revealed the trend of the topics from 2008 to 2022,which can assist scholars in identifying future trends.展开更多
目的通过文献计量学分析术后谵妄的研究现状、趋势和热点,为国内外研究提供新思路。方法检索Web of Science核心数据库中2002-2022年发表的术后谵妄相关文献(检索日期为2023年7月10日),对年度发表量、引用频率、发文国家、机构、期刊、...目的通过文献计量学分析术后谵妄的研究现状、趋势和热点,为国内外研究提供新思路。方法检索Web of Science核心数据库中2002-2022年发表的术后谵妄相关文献(检索日期为2023年7月10日),对年度发表量、引用频率、发文国家、机构、期刊、作者、关键词、研究方向等方面进行分析,并运用CiteSpace软件对文献的总体特征性进行可视化分析。结果共纳入1208篇文献,2002-2022年术后谵妄相关文献年发表量呈上升趋势;美国是发文最多的国家,其次是中国;发文量前两位作者是Inouye Sharon和Marcantonio Edward R;发文最多的机构是哈佛大学;老年、长期住院、癌症、疼痛、髋关节骨折、心脏手术、腹部大手术和重症监护患者是术后谵妄研究的热点群体。术后谵妄预测模型的建立、预防性系统管理模型、患者远期结局等方面都具有较高的关注度。结论术后谵妄的研究正逐步增加,但是我国和发达国家仍存在一定差距。针对术后谵妄的系统规范性评估、预防、治疗是未来重点关注的研究方向。展开更多
目的基于Web of Science(WOS)数据库分析生酮饮食相关文献,明确该领域的研究热点与趋势。方法基于WOS核心数据库检索生酮饮食相关文献,时间范围为2013年1月1日—2022年12月31日。应用文献计量学方法和CiteSpace软件,对国家/地区、研究...目的基于Web of Science(WOS)数据库分析生酮饮食相关文献,明确该领域的研究热点与趋势。方法基于WOS核心数据库检索生酮饮食相关文献,时间范围为2013年1月1日—2022年12月31日。应用文献计量学方法和CiteSpace软件,对国家/地区、研究机构、发表期刊、关键词等文献特征进行统计学分析。结果本研究共获取有效文献4548篇,包括论著3317篇、综述1231篇。2013—2022年生酮饮食研究领域的发文量总体呈增长趋势,并于2021年达到峰值(756篇);年被引频次呈逐年增长趋势,于2022年达到峰值(25643次)。该领域发文量最多的国家和研究机构分别为美国(1695篇,占37.27%)和约翰·霍普金斯大学(88篇,占1.93%),且研究机构以高校为主。Nutrients载文量最多(241篇,占5.30%),Epilepsia的篇均被引频次最高(33.19次)。被引频次前10位的文献中,5篇文献阐述了酮体在疾病治疗中的代谢与作用机制,4篇文献的研究主题与癫痫相关。研究热点包括生酮饮食在癫痫与肥胖治疗中的应用和疗效评价,酮体的脂肪酸氧化、代谢、氧化应激、Warburg效应等常见调控机制,肠道菌群介导生酮饮食的作用研究;研究趋势为生酮饮食在心力衰竭中的应用前景。结论生酮饮食已被应用于多种疾病的治疗中,且其全球关注度持续增长,后续研究热点应聚焦于临床试验,以验证其临床疗效与耐受性。展开更多
This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burk...This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burkina Faso, which is undergoing rapid urbanization, faces major natural threats, particularly flooding, as demonstrated by the severe floods of 2009 that caused loss of life, injury, structural damage and economic losses in Ouagadougou. The aim of this research is to develop a web map highlighting the municipality’s flood-prone areas, with a view to informing and raising awareness of flood risk reduction. Using the Leaflet JavaScript mapping library, the study uses HTML, CSS and JavaScript to implement web mapping technology. Data on Ouagadougou’s flood zones is generated by a multi-criteria analysis combining Saaty’s AHP method and GIS in QGIS, integrating seven (7) parameters including hydrography, altitude, slope, rainfall, soil types, land use and soil moisture index. QGIS processes and maps the themes, PostgreSQL with PostGIS serves as the DBMS and GeoServer functions as the map server. The Web GIS platform allows users to visualize the different flood risks, from very low to very high, or the high-risk areas specific to Ouagadougou. The AHP calculations classify the municipality into five flood vulnerability zones: very low (24.48%), low (27.93%), medium (23.01%), high (17.11%) and very high (7.47%). Effective risk management requires communication and awareness-raising. This online mapping application serves as a tool for communication, management and flood prevention in Ouagadougou, helping to mitigate flood-related natural disasters.展开更多
Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of s...Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of solutions for this server is therefore growing continuously, these services are becoming more and more complex and expensive, without being able to fulfill the needs of the users. The absence of benchmarks for websites with dynamic content is the major obstacle to research in this area. These users place high demands on the speed of access to information on the Internet. This is why the performance of the web server is critically important. Several factors influence performance, such as server execution speed, network saturation on the internet or intranet, increased response time, and throughputs. By measuring these factors, we propose a performance evaluation strategy for servers that allows us to determine the actual performance of different servers in terms of user satisfaction. Furthermore, we identified performance characteristics such as throughput, resource utilization, and response time of a system through measurement and modeling by simulation. Finally, we present a simple queue model of an Apache web server, which reasonably represents the behavior of a saturated web server using the Simulink model in Matlab (Matrix Laboratory) and also incorporates sporadic incoming traffic. We obtain server performance metrics such as average response time and throughput through simulations. Compared to other models, our model is conceptually straightforward. The model has been validated through measurements and simulations during the tests that we conducted.展开更多
Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractic...Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractical for users to specify quantitative and exact preferences. Moreover, due to that Quality of Service (QoS) attributes are often interrelated, existing Web service selection approaches which employ weighted summation of QoS attribute values to compute the overall QoS of Web services may produce inaccurate results, since they do not take correlations among QoS attributes into account. To resolve these problems, a Web service selection framework considering user's preference priority is proposed, which incorporates a searching mechanism with QoS range setting to identify services satisfying the user's QoS constraints. With the identified service candidates, based on the idea of Principal Component Analysis (PCA), an algorithm of Web service selection named PCA-WSS (Web Service Selection based on PCA) is proposed, which can eliminate the correlations among QoS attributes and compute the overall QoS of Web services accurately. After computing the overall QoS for each service, the algorithm ranks the Web service candidates based on their overall QoS and recommends services with top QoS values to users. Finally, the effectiveness and feasibility of our approach are validated by experiments, i.e. the selected Web service by our approach is given high average evaluation than other ones by users and the time cost of PCA-WSS algorithm is not affected acutely by the number of service candidates.展开更多
Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown co...Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown correlation didn't make reliability analysis accurately based on existing GO methodology. So, a reliability analysis method used to deal with DICLFL considering shutdown correlation is provided based on GO methodology.Firstly, a new operator, which is used to describe DICLFL considering shutdown correlation,whose number is 1,is created and named as Type 9C operator. And then,the formulas of type 9C operator are derived based on Markov process theory. Finally,the new method presented in this paper is adopted to conduct the reliability analysis of an electro-hydraulic servo speed control system. The analysis result is compared with those of Monte Carlo simulation and fault tree analysis( FTA). The comparison results show that this new reliability analysis method based on GO methodology is feasible and meaningful for reliability analysis of repairable systems with DICLFL considering shutdown correlation.Meantime,it will be useful for more other applications.展开更多
Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, th...Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, the patient navigation model has shown its effectiveness in improving the quality of life among patients with chronic diseases and reducing the shortage of current healthcare resources in some area. This study aims to identify the current status and dilemma of the patient navigation model applied in colorectal cancer care in China. Methods: Bibliometric method was used to analyze published articles regarding the application of patient navigation model in colorectal cancer care retrieved from the Web of Science database. Statistics were presented using visualization method processed by the Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software. Results: 124 articles, from 2006 to 2018, covering 14 countries, involving 931 researchers, 356 institutions and 60 publications were obtained;American research papers are the largest components of the aforementioned articles;only one of them is written by Chinese authors. The 3 leading institutions in this domain are University OF Rochester, Ohio State University, Icahn School of Medicine at Mount Sinai, yet the distribution of authors is relatively decentralized. “Cancer” is the main journal that publishes the researches in this domain. Research hotspots are on “cancer prevention and screening”, “health disparities”, “economic evaluation”, “patient navigators”, and “ethnicity”. Conclusion: In China, the research on the patient navigation is still in its infancy. Therefore, the Chinese government should provide more endorsement to this particular area and encourage the cooperation with other countries. China, having a long way to go, should further explore patient navigation on colorectal cancer care and establish a model that matches its cultural backgrounds.展开更多
To detect security vulnerabilities in a web application,the security analyst must choose the best performance Security Analysis Static Tool(SAST)in terms of discovering the greatest number of security vulnerabilities ...To detect security vulnerabilities in a web application,the security analyst must choose the best performance Security Analysis Static Tool(SAST)in terms of discovering the greatest number of security vulnerabilities as possible.To compare static analysis tools for web applications,an adapted benchmark to the vulnerability categories included in the known standard Open Web Application Security Project(OWASP)Top Ten project is required.The information of the security effectiveness of a commercial static analysis tool is not usually a publicly accessible research and the state of the art on static security tool analyzers shows that the different design and implementation of those tools has different effectiveness rates in terms of security performance.Given the significant cost of commercial tools,this paper studies the performance of seven static tools using a new methodology proposal and a new benchmark designed for vulnerability categories included in the known standard OWASP Top Ten project.Thus,the practitioners will have more precise information to select the best tool using a benchmark adapted to the last versions of OWASP Top Ten project.The results of this work have been obtaining using widely acceptable metrics to classify them according to three different degree of web application criticality.展开更多
This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static...This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static and dynamic analysis.The architectural elegancy of the diagrid structure attributed to its triangular leaning member configuration and high structural redundancy make this system a desirable choice for tall building design.However,forming a stable energy dissipation mechanism in diagrid framing remains to be investigated to expand its use in regions with high seismicity.To address this issue,a diagrid framing design is proposed here which provides a competitive design option in highly seismic regions through its increased ductility and improved energy dissipation capacity provided by replaceable shear links interconnecting the diagonal members at their ends.The structural characteristics and seismic behavior(capacity,stiffness,energy dissipation,ductility) of the diagrid structural frame are demonstrated with a 21-story building diagrid frame subjected to nonlinear static and dynamic analysis.The findings from the nonlinear time history analysis verify that satisfactory seismic performance can be achieved by the proposed diagrid frame subjected to design basis earthquakes in California.In particular,one appealing feature of the proposed diagrid building is its reduced residual displacement after strong earthquakes.展开更多
文摘低温逆境已成为限制全球小麦稳产丰产与优质的主要农业气象灾害之一。为客观全面地了解全球小麦低温逆境领域的研究现状和发展趋势,基于Web of Science核心数据库中2000-2020年发表的以“小麦”和“低温”为研究主题的相关文献为数据源,利用CiteSpace可视化分析软件对检索到与主题密切相关的475篇文献从发文数量、发文国家、发文作者、研究机构、研究热点等方面进行统计分析。结果表明:自2000年以来,小麦低温逆境领域年发文数量总体呈波动上升趋势;以中国、美国和加拿大等国家为代表的农业大国均致力于该领域的研究;美国学者Skin⁃ner是该领域发文量最多的作者,与其他学者合作密切的有李向楠和Fowler;该领域文献多发表于《Molecular Genetics and Genomics》和《Annual Review of Plant Biology》等优质期刊上;俄罗斯科学院是该领域发文量最多的科研机构;耐低温小麦新品种培育、耐寒分子生物学研究以及提高小麦产质量等方面成为该领域的研究热点。
文摘In recent years, web technology carried on growing and at same time, the number of internet users increased significantly in number. Today, a Web server is capable of processing millions of requests per day, but during the peak period may collapse and becomes critical causing unavailability of the services offered by the servers. That is why Web server performance is a topic of great interest to many researchers. In this paper, we evaluate experimentally the impact of JSP and PHP dynamic content technology: JSP and PHP with access to a database of performance data of Apache Web server. Using the “ApacheBench” performance measurement tool, the approach is to compare the performances of four different configurations of a Web server, such as: Apache Web server implementing JSP technology with access to PostgreSQL database, Apache using PHP technology with the PostgreSQL as database, Apache Web server using the JSP technology with access to MySQL database, finally Apache and PHP with DBMS MySQL. At the end of this article, we also present a Simulink model of Web server performance based on the simple M/M/1 queue. During the modeling, the MATLAB software was used.
文摘Exponential increase in the quantity of user generated content in websites and social networks have resulted in the emergence of web intelligence approaches.Several natural language processing(NLP)tools are commonly used to examine the large quantity of data generated online.Particularly,sentiment analysis(SA)is an effective way of classifying the data into different classes of user opinions or sentiments.The latest advances in machine learning(ML)and deep learning(DL)approaches offer an intelligent way of analyzing sentiments.In this view,this study introduces a web intelligence with enhanced sunflower optimization based deep learning model for sentiment analysis(WIESFO-DLSA)technique.The major intention of the WIESFO-DLSA technique is to identify the expressions or sentiments that exist in the social networking data.The WIESFO-DLSA technique initially performs pre-processing and word2vec feature extraction processes to generate a meaningful set of features.At the same time,bidirectional long short term memory(BiLSTM)model is applied for classification of sentiments into different class labels.Moreover,an enhanced sunflower optimization(ESFO)algorithm is exploited to optimally adjust the hyperparameters of the BiLSTM model.A wide range of simulation analyses is performed to report the better outcomes of the WISFO-DLSA technique and the experimental outcomes ensured its promising performance under several measures.
基金This research was partly funded by the Traditional Chinese Medicine Science and Technology Development Plan Project of Jiangsu Province(ZT202113 to Haibing Hua)the Scientific Research Project of Jiangyin Association of Chinese Medicine(Y202205 to Yufeng Zhang)the ChengXing Talent Training Plan of Jiangyin Hospital of Traditional Chinese Medicine(2022 to Yufeng Zhang).
文摘Objective:With the development of Wendan decoction(WDD)and more literature on the research of WDD,we aimed to present an insight into WDD research using bibliometric analysis.Methods:We retrieved data from the Web of Science database from 2008 to 2022.Publication trends were examined using data from journals,authors,institutions,international collaborations,citations,and keywords from the online analytical platform Bibliometric(http://bibliometric.com).Results:Over the years,an increase in the use of keywords,including depression,insomnia,Alzheimer’s disease,schizophrenia,hippocampus,and insomnia,was observed.The outcomes of the analysis revealed that topics related to WDD have become increasingly prevalent in the last five years,and the internationally recognized application of WDD is mainly neuropsychiatric diseases.Conclusion:We exhibited WDD research progress by identifying and evaluating WDD-focused articles.Our analysis revealed the trend of the topics from 2008 to 2022,which can assist scholars in identifying future trends.
文摘目的通过文献计量学分析术后谵妄的研究现状、趋势和热点,为国内外研究提供新思路。方法检索Web of Science核心数据库中2002-2022年发表的术后谵妄相关文献(检索日期为2023年7月10日),对年度发表量、引用频率、发文国家、机构、期刊、作者、关键词、研究方向等方面进行分析,并运用CiteSpace软件对文献的总体特征性进行可视化分析。结果共纳入1208篇文献,2002-2022年术后谵妄相关文献年发表量呈上升趋势;美国是发文最多的国家,其次是中国;发文量前两位作者是Inouye Sharon和Marcantonio Edward R;发文最多的机构是哈佛大学;老年、长期住院、癌症、疼痛、髋关节骨折、心脏手术、腹部大手术和重症监护患者是术后谵妄研究的热点群体。术后谵妄预测模型的建立、预防性系统管理模型、患者远期结局等方面都具有较高的关注度。结论术后谵妄的研究正逐步增加,但是我国和发达国家仍存在一定差距。针对术后谵妄的系统规范性评估、预防、治疗是未来重点关注的研究方向。
文摘目的基于Web of Science(WOS)数据库分析生酮饮食相关文献,明确该领域的研究热点与趋势。方法基于WOS核心数据库检索生酮饮食相关文献,时间范围为2013年1月1日—2022年12月31日。应用文献计量学方法和CiteSpace软件,对国家/地区、研究机构、发表期刊、关键词等文献特征进行统计学分析。结果本研究共获取有效文献4548篇,包括论著3317篇、综述1231篇。2013—2022年生酮饮食研究领域的发文量总体呈增长趋势,并于2021年达到峰值(756篇);年被引频次呈逐年增长趋势,于2022年达到峰值(25643次)。该领域发文量最多的国家和研究机构分别为美国(1695篇,占37.27%)和约翰·霍普金斯大学(88篇,占1.93%),且研究机构以高校为主。Nutrients载文量最多(241篇,占5.30%),Epilepsia的篇均被引频次最高(33.19次)。被引频次前10位的文献中,5篇文献阐述了酮体在疾病治疗中的代谢与作用机制,4篇文献的研究主题与癫痫相关。研究热点包括生酮饮食在癫痫与肥胖治疗中的应用和疗效评价,酮体的脂肪酸氧化、代谢、氧化应激、Warburg效应等常见调控机制,肠道菌群介导生酮饮食的作用研究;研究趋势为生酮饮食在心力衰竭中的应用前景。结论生酮饮食已被应用于多种疾病的治疗中,且其全球关注度持续增长,后续研究热点应聚焦于临床试验,以验证其临床疗效与耐受性。
文摘This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burkina Faso, which is undergoing rapid urbanization, faces major natural threats, particularly flooding, as demonstrated by the severe floods of 2009 that caused loss of life, injury, structural damage and economic losses in Ouagadougou. The aim of this research is to develop a web map highlighting the municipality’s flood-prone areas, with a view to informing and raising awareness of flood risk reduction. Using the Leaflet JavaScript mapping library, the study uses HTML, CSS and JavaScript to implement web mapping technology. Data on Ouagadougou’s flood zones is generated by a multi-criteria analysis combining Saaty’s AHP method and GIS in QGIS, integrating seven (7) parameters including hydrography, altitude, slope, rainfall, soil types, land use and soil moisture index. QGIS processes and maps the themes, PostgreSQL with PostGIS serves as the DBMS and GeoServer functions as the map server. The Web GIS platform allows users to visualize the different flood risks, from very low to very high, or the high-risk areas specific to Ouagadougou. The AHP calculations classify the municipality into five flood vulnerability zones: very low (24.48%), low (27.93%), medium (23.01%), high (17.11%) and very high (7.47%). Effective risk management requires communication and awareness-raising. This online mapping application serves as a tool for communication, management and flood prevention in Ouagadougou, helping to mitigate flood-related natural disasters.
文摘Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of solutions for this server is therefore growing continuously, these services are becoming more and more complex and expensive, without being able to fulfill the needs of the users. The absence of benchmarks for websites with dynamic content is the major obstacle to research in this area. These users place high demands on the speed of access to information on the Internet. This is why the performance of the web server is critically important. Several factors influence performance, such as server execution speed, network saturation on the internet or intranet, increased response time, and throughputs. By measuring these factors, we propose a performance evaluation strategy for servers that allows us to determine the actual performance of different servers in terms of user satisfaction. Furthermore, we identified performance characteristics such as throughput, resource utilization, and response time of a system through measurement and modeling by simulation. Finally, we present a simple queue model of an Apache web server, which reasonably represents the behavior of a saturated web server using the Simulink model in Matlab (Matrix Laboratory) and also incorporates sporadic incoming traffic. We obtain server performance metrics such as average response time and throughput through simulations. Compared to other models, our model is conceptually straightforward. The model has been validated through measurements and simulations during the tests that we conducted.
基金Supported by the National Natural Science Foundation of China(No.90818004and61100054)Program for New Century Excellent Talents in University(No.NCET-10-0140)+1 种基金Excellent Youth Foundation of Hunan Scientific Committee(No.11JJ1011)Scientific Research Fundof Hunan Educational Committee(No.09K085and11B048)
文摘Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractical for users to specify quantitative and exact preferences. Moreover, due to that Quality of Service (QoS) attributes are often interrelated, existing Web service selection approaches which employ weighted summation of QoS attribute values to compute the overall QoS of Web services may produce inaccurate results, since they do not take correlations among QoS attributes into account. To resolve these problems, a Web service selection framework considering user's preference priority is proposed, which incorporates a searching mechanism with QoS range setting to identify services satisfying the user's QoS constraints. With the identified service candidates, based on the idea of Principal Component Analysis (PCA), an algorithm of Web service selection named PCA-WSS (Web Service Selection based on PCA) is proposed, which can eliminate the correlations among QoS attributes and compute the overall QoS of Web services accurately. After computing the overall QoS for each service, the algorithm ranks the Web service candidates based on their overall QoS and recommends services with top QoS values to users. Finally, the effectiveness and feasibility of our approach are validated by experiments, i.e. the selected Web service by our approach is given high average evaluation than other ones by users and the time cost of PCA-WSS algorithm is not affected acutely by the number of service candidates.
基金Technical Basis Projects of China's MIIT(Nos.ZQ092012B003,2012090003)
文摘Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown correlation didn't make reliability analysis accurately based on existing GO methodology. So, a reliability analysis method used to deal with DICLFL considering shutdown correlation is provided based on GO methodology.Firstly, a new operator, which is used to describe DICLFL considering shutdown correlation,whose number is 1,is created and named as Type 9C operator. And then,the formulas of type 9C operator are derived based on Markov process theory. Finally,the new method presented in this paper is adopted to conduct the reliability analysis of an electro-hydraulic servo speed control system. The analysis result is compared with those of Monte Carlo simulation and fault tree analysis( FTA). The comparison results show that this new reliability analysis method based on GO methodology is feasible and meaningful for reliability analysis of repairable systems with DICLFL considering shutdown correlation.Meantime,it will be useful for more other applications.
文摘Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, the patient navigation model has shown its effectiveness in improving the quality of life among patients with chronic diseases and reducing the shortage of current healthcare resources in some area. This study aims to identify the current status and dilemma of the patient navigation model applied in colorectal cancer care in China. Methods: Bibliometric method was used to analyze published articles regarding the application of patient navigation model in colorectal cancer care retrieved from the Web of Science database. Statistics were presented using visualization method processed by the Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software. Results: 124 articles, from 2006 to 2018, covering 14 countries, involving 931 researchers, 356 institutions and 60 publications were obtained;American research papers are the largest components of the aforementioned articles;only one of them is written by Chinese authors. The 3 leading institutions in this domain are University OF Rochester, Ohio State University, Icahn School of Medicine at Mount Sinai, yet the distribution of authors is relatively decentralized. “Cancer” is the main journal that publishes the researches in this domain. Research hotspots are on “cancer prevention and screening”, “health disparities”, “economic evaluation”, “patient navigators”, and “ethnicity”. Conclusion: In China, the research on the patient navigation is still in its infancy. Therefore, the Chinese government should provide more endorsement to this particular area and encourage the cooperation with other countries. China, having a long way to go, should further explore patient navigation on colorectal cancer care and establish a model that matches its cultural backgrounds.
文摘To detect security vulnerabilities in a web application,the security analyst must choose the best performance Security Analysis Static Tool(SAST)in terms of discovering the greatest number of security vulnerabilities as possible.To compare static analysis tools for web applications,an adapted benchmark to the vulnerability categories included in the known standard Open Web Application Security Project(OWASP)Top Ten project is required.The information of the security effectiveness of a commercial static analysis tool is not usually a publicly accessible research and the state of the art on static security tool analyzers shows that the different design and implementation of those tools has different effectiveness rates in terms of security performance.Given the significant cost of commercial tools,this paper studies the performance of seven static tools using a new methodology proposal and a new benchmark designed for vulnerability categories included in the known standard OWASP Top Ten project.Thus,the practitioners will have more precise information to select the best tool using a benchmark adapted to the last versions of OWASP Top Ten project.The results of this work have been obtaining using widely acceptable metrics to classify them according to three different degree of web application criticality.
基金the University of Maryland for providing partial financial support for this research project
文摘This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static and dynamic analysis.The architectural elegancy of the diagrid structure attributed to its triangular leaning member configuration and high structural redundancy make this system a desirable choice for tall building design.However,forming a stable energy dissipation mechanism in diagrid framing remains to be investigated to expand its use in regions with high seismicity.To address this issue,a diagrid framing design is proposed here which provides a competitive design option in highly seismic regions through its increased ductility and improved energy dissipation capacity provided by replaceable shear links interconnecting the diagonal members at their ends.The structural characteristics and seismic behavior(capacity,stiffness,energy dissipation,ductility) of the diagrid structural frame are demonstrated with a 21-story building diagrid frame subjected to nonlinear static and dynamic analysis.The findings from the nonlinear time history analysis verify that satisfactory seismic performance can be achieved by the proposed diagrid frame subjected to design basis earthquakes in California.In particular,one appealing feature of the proposed diagrid building is its reduced residual displacement after strong earthquakes.
