River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is reco...River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA) using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.展开更多
BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufactur...BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufacturing of these two new large reusable launching vehicle models is a response to growing demand in the commercial space market,said the China Aerospace Science and Technology Corporation.展开更多
This paper presents the systematic Summation of the investigation and the re-examination results,and the overall analysis of the quntity, quality, distribution, principle and way of development of water resource in Sa...This paper presents the systematic Summation of the investigation and the re-examination results,and the overall analysis of the quntity, quality, distribution, principle and way of development of water resource in Sanjiang plain.展开更多
In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of lear...In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of learner. We conduct a comparative study for various ensemble methods (Bagging, Boosting, and Voting) with simple classifiers in perspective of classification. We also evaluate the effectiveness of these classifiers (both ensemble and simple) on five different data sets of varying session length. Presently the results of web server log analyzers are not very much reliable because the input log files are highly inflated by sessions of automated web traverse software’s, known as web robots. Presence of web robots access traffic entries in web server log repositories imposes a great challenge to extract any actionable and usable knowledge about browsing behavior of actual visitors. So web robots sessions need accurate and fast detection from web server log repositories to extract knowledge about genuine visitors and to produce correct results of log analyzers.展开更多
In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a grap...In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated technology.The coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying boundaries.The coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the LRE.The simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured values.The root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,respectively.Furthermore,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(S.heteroptera)matches with the distribution of S.heteroptera obtained from the high-resolution remote sensing satellite images during the same time period.The ratio of the simulated weighted usable area(WUA)of S.heteroptera to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of S.heteroptera in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation.展开更多
With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of t...With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of the development lifecycle. There are also many proposed methodologies where the security measures are considered at requirement engineering stage of the development lifecycle, but many of them still do not seem adequate for applicability due to the reason that these approaches do not provide sufficient support for mapping the security requirements to the later stages of development. So, we are in need of a software requirement engineering approach, which is not only helpful in security requirement specification at requirement engineering stage but also provides support for using the specified security requirements at later stages of development. To meet this requirement, we introduce a new method Secure and Traceable Requirement Engineering Process (STREP). This method also helps the non-security-expert requirement engineers to specify requirements in such a way that the specified requirements can be used to derive security related test cases. STREP method not only deals with security issues of the system at requirement engineering stage, but also makes the security requirements more traceable to be used at later stages of development lifecycle, and as a result, secure systems are produced that are also usable as the customer wishes.展开更多
The ever-increasing amount of major security incidents has led to an emerging interest in cooperative approaches to encounter cyber threats.To enable cooperation in detecting and preventing attacks it is an inevitable...The ever-increasing amount of major security incidents has led to an emerging interest in cooperative approaches to encounter cyber threats.To enable cooperation in detecting and preventing attacks it is an inevitable necessity to have structured and standardized formats to describe an incident.Corresponding formats are complex and of an extensive nature as they are often designed for automated processing and exchange.These characteristics hamper the readability and,therefore,prevent humans from understanding the documented incident.This is a major problem since the success and effectiveness of any security measure rely heavily on the contribution of security experts.To meet these shortcomings we propose a visual analytics concept enabling security experts to analyze and enrich semi-structured cyber threat intelligence information.Our approach combines an innovative way of persisting this data with an interactive visualization component to analyze and edit the threat information.We demonstrate the feasibility of our concept using the Structured Threat Information eXpression,the state-ofthe-art format for reporting cyber security issues.展开更多
With the background of offshore wind energy projects, this paper studies aerodynamic performance and geometric characteristics of large capacity wind turbine rotors (1 to 10 MW), and the main characteristic paramete...With the background of offshore wind energy projects, this paper studies aerodynamic performance and geometric characteristics of large capacity wind turbine rotors (1 to 10 MW), and the main characteristic parameters such as the rated wind speed, blade tip speed, and rotor solidity. We show that the essential criterion of a high- performance wind turbine is a highest possible annual usable energy pattern factor and a smallest possible dimension, capturing the maximum wind energy and producing the maximum annual power. The influence of the above-mentioned three parameters on the pattern factor and rotor geometry of wind turbine operated in China's offshore meteoro- logical environment is investigated. The variation patterns of aerodynamic and geometric parameters are obtained, analyzed, and compared with each other. The present method for aerodynamic analysis and its results can form a basis for evaluating aerodynamic performance of large-scale offshore wind turbine rotors.展开更多
The apparent contradiction between usability and security has been discussed in the literature for several years.This continuous trade-off requires be acknowledging and handling whenever security solutions are introdu...The apparent contradiction between usability and security has been discussed in the literature for several years.This continuous trade-off requires be acknowledging and handling whenever security solutions are introduced.However,some progressive analysts point out that present security solutions are usually very difficult for several users,and they have expressed a willingness to simplify the security product user experience.Usable security is still mostly unexplored territory in computer science.Which we are all aware with security and usability on many levels,usable security has received little operational attention.Companies have recently focused primarily on usable security.As consumers prefer to discard unsatisfactory solutions,attaining well-balanced degrees of both is a prerequisite for adequate security.Usability should be examined from the viewpoint of security to be properly assessed.The aim of this research study is to explore and discuss universally accepted and solutionindependent factors influencing the perceived usable-security of institutional websites.An integrated Hesitant Fuzzy Linguistic term sets based technique was chosen as the methodology,and the experts and academicians opinion were collected.The use of predetermined selection criteria resulted in the compilation of statistical findings and were used to determine the usable-security of five different instituational websites.展开更多
If terrorists can obtain a sufficient quantity of weapons usable nuclear material,they could design,construct and detonate a nuclear bomb.The consequences of such a catastrophe would reverberate around the globe,with ...If terrorists can obtain a sufficient quantity of weapons usable nuclear material,they could design,construct and detonate a nuclear bomb.The consequences of such a catastrophe would reverberate around the globe,with thousands of casualties,disruptions to economic markets,long-term implications for public health and the environment,and risks to civil liberties-not to mention the staggering cost of any response.展开更多
The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the ...The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the most efficient way to access and use them For the biologist, running bioinformatics analyses involve a time-consuming management of data and tools. Users need support to organize their work, retrieve parameters and reproduce their analyses. They also need to be able to combine their analytic tools using a safe data flow software mechanism. Finally we have designed a system, Bioinfo-Portal, to provide a flexible and usable web environment for defining and running bioinformatics analyses. It embeds simple yet powerful data management features that allow the user to reproduce analyses and to combine tools using an adobe flex tool. Bioinfo-Portal can also act as a front end to provide a unified view of already-existing collections of bioinformatics resources. Users can analyze genomic and proteomic data by using the tools that has been integrated in the portal (tools for alignments, dotplots, motif detection, domain analysis, profile searching and tertiary structure prediction). The sequences that user obtained from portal's nucleotide and protein databases are easily analyzed by the portal tools on the same interface in no time. User can also take benefit from the animations.展开更多
Source:MIT Technology ntroduction Not all breakthroughs are created equal.Some arrive more or less as usable things;others mainly set the stage for innovations that emerge later,and we have to estimate when that will ...Source:MIT Technology ntroduction Not all breakthroughs are created equal.Some arrive more or less as usable things;others mainly set the stage for innovations that emerge later,and we have to estimate when that will be.But we’d bet that every one of the milestones on this list will be worth following in the coming years.1.Magic展开更多
In 1803, the USA paid France $15,000,000 for the Louisiana Territory(地域, 领土), an area more than four times the size of France. The land which was bought included everything between the Rocky Mountains and the Miss...In 1803, the USA paid France $15,000,000 for the Louisiana Territory(地域, 领土), an area more than four times the size of France. The land which was bought included everything between the Rocky Mountains and the Mississippi River except Texas. The main port for the second longest river system in the world was within this territory. Although few realized it at that time, the purchase included the vast forests of Arkansas and Minnesota, the oilfields of Oklahoma, the cornfields of Iowa, the wheat lands of the Dakotas, the copper, silver, and gold of Colorado and Montana, the rice and sugar of Louisiana. Without doubt, the Louisiana Purchase was one of the greatest events in the history of the United States. In a single action, as planned, a thirdclass nation successfully doubled its size, united its states and population, and became a great power in the world.展开更多
文摘River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA) using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.
文摘BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufacturing of these two new large reusable launching vehicle models is a response to growing demand in the commercial space market,said the China Aerospace Science and Technology Corporation.
文摘This paper presents the systematic Summation of the investigation and the re-examination results,and the overall analysis of the quntity, quality, distribution, principle and way of development of water resource in Sanjiang plain.
文摘In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of learner. We conduct a comparative study for various ensemble methods (Bagging, Boosting, and Voting) with simple classifiers in perspective of classification. We also evaluate the effectiveness of these classifiers (both ensemble and simple) on five different data sets of varying session length. Presently the results of web server log analyzers are not very much reliable because the input log files are highly inflated by sessions of automated web traverse software’s, known as web robots. Presence of web robots access traffic entries in web server log repositories imposes a great challenge to extract any actionable and usable knowledge about browsing behavior of actual visitors. So web robots sessions need accurate and fast detection from web server log repositories to extract knowledge about genuine visitors and to produce correct results of log analyzers.
基金Project supported by the National Key Research and Development Program of China(Grant No.2019YFC1407700)the National Natural Science Foundation of China(Grant No.51779038).
文摘In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated technology.The coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying boundaries.The coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the LRE.The simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured values.The root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,respectively.Furthermore,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(S.heteroptera)matches with the distribution of S.heteroptera obtained from the high-resolution remote sensing satellite images during the same time period.The ratio of the simulated weighted usable area(WUA)of S.heteroptera to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of S.heteroptera in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation.
文摘With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of the development lifecycle. There are also many proposed methodologies where the security measures are considered at requirement engineering stage of the development lifecycle, but many of them still do not seem adequate for applicability due to the reason that these approaches do not provide sufficient support for mapping the security requirements to the later stages of development. So, we are in need of a software requirement engineering approach, which is not only helpful in security requirement specification at requirement engineering stage but also provides support for using the specified security requirements at later stages of development. To meet this requirement, we introduce a new method Secure and Traceable Requirement Engineering Process (STREP). This method also helps the non-security-expert requirement engineers to specify requirements in such a way that the specified requirements can be used to derive security related test cases. STREP method not only deals with security issues of the system at requirement engineering stage, but also makes the security requirements more traceable to be used at later stages of development lifecycle, and as a result, secure systems are produced that are also usable as the customer wishes.
基金supported by the Federal Ministry of Education and Research,Germany,as part of the BMBF DINGfest project。
文摘The ever-increasing amount of major security incidents has led to an emerging interest in cooperative approaches to encounter cyber threats.To enable cooperation in detecting and preventing attacks it is an inevitable necessity to have structured and standardized formats to describe an incident.Corresponding formats are complex and of an extensive nature as they are often designed for automated processing and exchange.These characteristics hamper the readability and,therefore,prevent humans from understanding the documented incident.This is a major problem since the success and effectiveness of any security measure rely heavily on the contribution of security experts.To meet these shortcomings we propose a visual analytics concept enabling security experts to analyze and enrich semi-structured cyber threat intelligence information.Our approach combines an innovative way of persisting this data with an interactive visualization component to analyze and edit the threat information.We demonstrate the feasibility of our concept using the Structured Threat Information eXpression,the state-ofthe-art format for reporting cyber security issues.
基金supported by the National Basic Research Program of China (973 Program) (No. 2007CB714605)
文摘With the background of offshore wind energy projects, this paper studies aerodynamic performance and geometric characteristics of large capacity wind turbine rotors (1 to 10 MW), and the main characteristic parameters such as the rated wind speed, blade tip speed, and rotor solidity. We show that the essential criterion of a high- performance wind turbine is a highest possible annual usable energy pattern factor and a smallest possible dimension, capturing the maximum wind energy and producing the maximum annual power. The influence of the above-mentioned three parameters on the pattern factor and rotor geometry of wind turbine operated in China's offshore meteoro- logical environment is investigated. The variation patterns of aerodynamic and geometric parameters are obtained, analyzed, and compared with each other. The present method for aerodynamic analysis and its results can form a basis for evaluating aerodynamic performance of large-scale offshore wind turbine rotors.
基金Funding for this study was received from the Deanship of Scientific Research(DSR)at King Abdulaziz University,Jeddah,Kingdom of Saudi Arabia under the Grant No.G:095-611-14422.
文摘The apparent contradiction between usability and security has been discussed in the literature for several years.This continuous trade-off requires be acknowledging and handling whenever security solutions are introduced.However,some progressive analysts point out that present security solutions are usually very difficult for several users,and they have expressed a willingness to simplify the security product user experience.Usable security is still mostly unexplored territory in computer science.Which we are all aware with security and usability on many levels,usable security has received little operational attention.Companies have recently focused primarily on usable security.As consumers prefer to discard unsatisfactory solutions,attaining well-balanced degrees of both is a prerequisite for adequate security.Usability should be examined from the viewpoint of security to be properly assessed.The aim of this research study is to explore and discuss universally accepted and solutionindependent factors influencing the perceived usable-security of institutional websites.An integrated Hesitant Fuzzy Linguistic term sets based technique was chosen as the methodology,and the experts and academicians opinion were collected.The use of predetermined selection criteria resulted in the compilation of statistical findings and were used to determine the usable-security of five different instituational websites.
文摘If terrorists can obtain a sufficient quantity of weapons usable nuclear material,they could design,construct and detonate a nuclear bomb.The consequences of such a catastrophe would reverberate around the globe,with thousands of casualties,disruptions to economic markets,long-term implications for public health and the environment,and risks to civil liberties-not to mention the staggering cost of any response.
文摘The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the most efficient way to access and use them For the biologist, running bioinformatics analyses involve a time-consuming management of data and tools. Users need support to organize their work, retrieve parameters and reproduce their analyses. They also need to be able to combine their analytic tools using a safe data flow software mechanism. Finally we have designed a system, Bioinfo-Portal, to provide a flexible and usable web environment for defining and running bioinformatics analyses. It embeds simple yet powerful data management features that allow the user to reproduce analyses and to combine tools using an adobe flex tool. Bioinfo-Portal can also act as a front end to provide a unified view of already-existing collections of bioinformatics resources. Users can analyze genomic and proteomic data by using the tools that has been integrated in the portal (tools for alignments, dotplots, motif detection, domain analysis, profile searching and tertiary structure prediction). The sequences that user obtained from portal's nucleotide and protein databases are easily analyzed by the portal tools on the same interface in no time. User can also take benefit from the animations.
文摘Source:MIT Technology ntroduction Not all breakthroughs are created equal.Some arrive more or less as usable things;others mainly set the stage for innovations that emerge later,and we have to estimate when that will be.But we’d bet that every one of the milestones on this list will be worth following in the coming years.1.Magic
文摘In 1803, the USA paid France $15,000,000 for the Louisiana Territory(地域, 领土), an area more than four times the size of France. The land which was bought included everything between the Rocky Mountains and the Mississippi River except Texas. The main port for the second longest river system in the world was within this territory. Although few realized it at that time, the purchase included the vast forests of Arkansas and Minnesota, the oilfields of Oklahoma, the cornfields of Iowa, the wheat lands of the Dakotas, the copper, silver, and gold of Colorado and Montana, the rice and sugar of Louisiana. Without doubt, the Louisiana Purchase was one of the greatest events in the history of the United States. In a single action, as planned, a thirdclass nation successfully doubled its size, united its states and population, and became a great power in the world.