The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application d...The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application development.The carrying capacity of railway 5G-R has been greatly improved,mainly for wide-area train-ground communication services such as dispatching communication,train control and train operation safety monitoring.However,for large passenger stations,freight yards,maintenance bases and other places with densely populated railway operators,it is unable to carry overall railway service applications limited by the spectrum bandwidth of 5G private networks,so it is necessary to consider various radio technologies for supplementation.This paper also elaborates the railway service application scenarios,analyzes the characteristics of radio communication technologies such as 5G mmWave and the 6th-generation wireless LAN technology(Wi-Fi6),and discusses the schemes of multi-technology convergence carrying railway 5G service applications.展开更多
As the next-generation mobile broadband networks, Ultra Mobile Broadband (UMB) and Long Term Evolution (LTE) continue to improve the mobile broadband performance and capacity by allowing operators to leverage new spec...As the next-generation mobile broadband networks, Ultra Mobile Broadband (UMB) and Long Term Evolution (LTE) continue to improve the mobile broadband performance and capacity by allowing operators to leverage new spectrum with wider bandwidths of 10 MHz and more. This will in turn enable the operators to address exciting market opportunities and service proliferation in high tele-density areas. This article discusses the drivers for the next-generation mobile broadband networks, and market opportunities of UMB and LTE. There are at least three key drivers for the networks: increasing device capabilities; growing mobile data consumption; and maintaining operator profitability. The opportunities include laptops, Personal Digital Assistants (PDAs) and fixed broadband access, premium Video on Demand (VOD)/Music on Demand (MOD) services, multimedia upload and exchange services, consumer electronics and business applications for vertical markets.展开更多
The paper introduces two typical 3G services:the mobile multimedia short message service and the streaming media service. The former is considered as a strong driving force to promote the development of 3G services an...The paper introduces two typical 3G services:the mobile multimedia short message service and the streaming media service. The former is considered as a strong driving force to promote the development of 3G services and applications.The latter is regarded as a typical service on future 3G networks.As supporting technologies of 3G services,open service architecture and open mobile architecture are also discussed.展开更多
Fengyun meteorological satellites have undergone a series of significant developments over the past 50 years.Two generations,four types,and 21 Fengyun satellites have been developed and launched,with 9 currently opera...Fengyun meteorological satellites have undergone a series of significant developments over the past 50 years.Two generations,four types,and 21 Fengyun satellites have been developed and launched,with 9 currently operational in orbit.The data obtained from Fengyun satellites is employed in a multitude of applications,including weather forecasting,meteorological disaster prevention and reduction,climate change,global environmental monitoring,and space weather.These data products and services are made available to the global community,resulting in tangible social and economic benefits.In 2023,two Fengyun meteorological satellites were successfully launched.This report presents an overview of the two recently launched Fengyun satellites and currently in orbit Fengyun satellites,including an evaluation of their remote sensing instruments since 2022.Additionally,it addresses the subject of Fengyun satellite data archiving,data services,application services,international cooperation,and supporting activities.Furthermore,the development prospects have been outlined.展开更多
For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more compl...For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more complicated, The complexity of these applications poses problems such as reuse, installation, administration and evolution of applications. The development of applications is related to the evolution of paradigms and approaches to developing them. This paper presents different approaches and paradigms of development starting with the procedural approach, coming up for service, through the component and object-oriented approaches. Also, for each of the approaches we determine the advantages and limitations.展开更多
Increasing popularity of Android is making its security issue more crucial nowadays. This paper focuses on one-stop solution to secure Android device against information security and theft. Proposed application protec...Increasing popularity of Android is making its security issue more crucial nowadays. This paper focuses on one-stop solution to secure Android device against information security and theft. Proposed application protects Android device against theft and helps to control Android device by SMS or using internet connection. By this application once the user has configured the account for anti theft, user can remotely track, sound a loud siren, lock, secretly capture photo of an intruder who tries to break in, get randomly recorded voice of intruder, get thief identity using device web history and can able to wipe all your private data. This data and tracking information will be stored in one central web server database and one can access it anytime through login.展开更多
High availability is a critical mission for business system. At first, an instance of business system OPENSTOCK for pharmacy is introduced including both client and server sides. Secondly, a solution to the high avail...High availability is a critical mission for business system. At first, an instance of business system OPENSTOCK for pharmacy is introduced including both client and server sides. Secondly, a solution to the high availability of this system is given in detail, including design and implementation. The essentiality of this solution consists of scope of system information, system parameter tables of service status, schedule strategies of load ba lance and how to acquire system parameters and detect service states. The solution proposed is scalable and application oriented and supporting load balance for high performance and fault tolerate for high reliability. This application system has been applied and verified realistically, and the features of this business system derived in this paper have been achieved.展开更多
While the market potentials and impacts of web-based e-commerce are still in the ascendant, the advances in wireless technologies and mobile networks have brought about a new business opportunity and research attentio...While the market potentials and impacts of web-based e-commerce are still in the ascendant, the advances in wireless technologies and mobile networks have brought about a new business opportunity and research attention, what is termed mobile commerce. Commonly, mobile commerce is considered to be another new application of existing web-based e-commerce onto wireless networks, but as an independent business area, mobile commerce has its own advantages and challenges as opposed to traditional e-commerce applications. This paper focuses on exploring the unique features of mobile commerce as compared with traditional e-commerce. Also, there are still some limitations arisen in m-commerce in contrast to web-based e-commerce. Finally, current state of mobile commerce in Japan is presented in brief, with an introduction of several cases involving mobile commerce applications in today's marketplace.展开更多
Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only f...Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only for avoiding redundant e-government IS development but also for improving collaboration among government agencies. Two research questions were explored: what are the factors influencing the performance of SEIS? Will mandatory SEIS create a better performance than non-mandatory SEIS? Specifically, the use of five categories of IS aspects--information system quality, online service quality, offline service quality, diffusion modes and standard network size—is proposed to understand the performance of SEIS through applying both survey study and simulation study. The results show that information system quality and online service quality of SEIS have strong effects on users' expectation and users' satisfaction, which thereafter promotes the performance of SEIS. Government agencies' offline service quality shows a significant effect on users' satisfaction while not on users' expectation. Furthermore, the diffusion speed of SEIS in non-mandatory and mandatory modes and the standard network size also have great influence on the utility of SEIS.展开更多
In the context of global warming,China is facing with increasing climate risks.It is imperative to develop quantitative indices to reflect the climate risks caused by extreme weather/climate events and adverse climati...In the context of global warming,China is facing with increasing climate risks.It is imperative to develop quantitative indices to reflect the climate risks caused by extreme weather/climate events and adverse climatic conditions in association with different industries.Based on the observations at 2288 meteorological stations in China and the meteorological disasters data,a set of indices are developed to measure climate risks due to water-logging,drought,high temperature,cryogenic freezing,and typhoon.A statistical method is then used to construct an overall climate risk index(CRI)for China from these individual indices.There is a good correspondence between these indices and historical climatic conditions.The CRI,the index of water-logging by rain,and the high temperature index increase at a rate of 0.28,0.37,and 0.65 per decade,respectively,from 1961 to 2016.The cryogenic freezing index is closely related to changes in the consumer price index for food.The high temperature index is correlated with the consumption of energy and electricity.The correlation between the yearly growth in claims on household property insurance and the sum of the water-logging index and the typhoon index in the same year is as high as 0.70.Both the growth rate of claims on agricultural insurance and the annual growth rate of hospital inpatients are positively correlated with the CRI.The year-on-year growth in the number of domestic tourists is significantly negatively correlated with the CRI in the same year.More efforts are needed to develop regional CRIs.展开更多
In recent years,IoV(Internet of Vehicles)has become one of the most active research elds in network and intelligent transportation system.As an open converged network,IoV plays an important role in solving various dri...In recent years,IoV(Internet of Vehicles)has become one of the most active research elds in network and intelligent transportation system.As an open converged network,IoV plays an important role in solving various driving and traffc problems by advanced information and communications technology.We review the existing notions of IoV from di erent perspectives.Then,we provide our notion from a network point of view and propose a novel IoV architecture with four layers.Particularly,a novel layer named coordinative computing control layer is separated from the application layer.The novel layer is used for solving the coordinative computing and control problems for human-vehicle-environment.After summarizing the key technologies in IoV architecture,we construct a VV(Virtual Vehicle),which is an integrated image of driver and vehicle in networks.VVs can interact with each other in cyber space by providing traffc service and sharing sensing data coordinately,which can solve the communication bottleneck in physical space.Finally,an extended IoV architecture based on VVs is proposed.展开更多
Point of interest(POI)recommendation is one of the most important tasks in location-based social networks(LBSN).The existing recommendation methods face two challenges:(1)the cold start problem caused by data sparsity...Point of interest(POI)recommendation is one of the most important tasks in location-based social networks(LBSN).The existing recommendation methods face two challenges:(1)the cold start problem caused by data sparsity;(2)underutilization of the abundant side information besides user-POI interaction in large-scale data.Recent research shows that a user’s social relationship can be used to solve the cold start problem to some extent.The deep neural network learns users’long term and short term preferences to improve the recommendation quality.Therefore,this paper proposes a POI recommendation model called SSANet,applying side information(S)and self-attention(SA)to provide the high-satisfaction POI recommendations for users.Specifically,first,the user-POI interaction matrix were constructed by users history data to represents the user hidden representation;second,the side information includes rating scores,access frequency,social relationship,and geographic information were used to extract users preference;third,we use self-attention mechanism to learn user long term and short term preference.The experimental results on the real LBSN datasets show that the recommendation performance of the SSANet model is better than the existing POI recommendation model.展开更多
文摘The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application development.The carrying capacity of railway 5G-R has been greatly improved,mainly for wide-area train-ground communication services such as dispatching communication,train control and train operation safety monitoring.However,for large passenger stations,freight yards,maintenance bases and other places with densely populated railway operators,it is unable to carry overall railway service applications limited by the spectrum bandwidth of 5G private networks,so it is necessary to consider various radio technologies for supplementation.This paper also elaborates the railway service application scenarios,analyzes the characteristics of radio communication technologies such as 5G mmWave and the 6th-generation wireless LAN technology(Wi-Fi6),and discusses the schemes of multi-technology convergence carrying railway 5G service applications.
文摘As the next-generation mobile broadband networks, Ultra Mobile Broadband (UMB) and Long Term Evolution (LTE) continue to improve the mobile broadband performance and capacity by allowing operators to leverage new spectrum with wider bandwidths of 10 MHz and more. This will in turn enable the operators to address exciting market opportunities and service proliferation in high tele-density areas. This article discusses the drivers for the next-generation mobile broadband networks, and market opportunities of UMB and LTE. There are at least three key drivers for the networks: increasing device capabilities; growing mobile data consumption; and maintaining operator profitability. The opportunities include laptops, Personal Digital Assistants (PDAs) and fixed broadband access, premium Video on Demand (VOD)/Music on Demand (MOD) services, multimedia upload and exchange services, consumer electronics and business applications for vertical markets.
文摘The paper introduces two typical 3G services:the mobile multimedia short message service and the streaming media service. The former is considered as a strong driving force to promote the development of 3G services and applications.The latter is regarded as a typical service on future 3G networks.As supporting technologies of 3G services,open service architecture and open mobile architecture are also discussed.
基金Supported by National Natural Science Foundation of China(42274217)。
文摘Fengyun meteorological satellites have undergone a series of significant developments over the past 50 years.Two generations,four types,and 21 Fengyun satellites have been developed and launched,with 9 currently operational in orbit.The data obtained from Fengyun satellites is employed in a multitude of applications,including weather forecasting,meteorological disaster prevention and reduction,climate change,global environmental monitoring,and space weather.These data products and services are made available to the global community,resulting in tangible social and economic benefits.In 2023,two Fengyun meteorological satellites were successfully launched.This report presents an overview of the two recently launched Fengyun satellites and currently in orbit Fengyun satellites,including an evaluation of their remote sensing instruments since 2022.Additionally,it addresses the subject of Fengyun satellite data archiving,data services,application services,international cooperation,and supporting activities.Furthermore,the development prospects have been outlined.
文摘For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more complicated, The complexity of these applications poses problems such as reuse, installation, administration and evolution of applications. The development of applications is related to the evolution of paradigms and approaches to developing them. This paper presents different approaches and paradigms of development starting with the procedural approach, coming up for service, through the component and object-oriented approaches. Also, for each of the approaches we determine the advantages and limitations.
文摘Increasing popularity of Android is making its security issue more crucial nowadays. This paper focuses on one-stop solution to secure Android device against information security and theft. Proposed application protects Android device against theft and helps to control Android device by SMS or using internet connection. By this application once the user has configured the account for anti theft, user can remotely track, sound a loud siren, lock, secretly capture photo of an intruder who tries to break in, get randomly recorded voice of intruder, get thief identity using device web history and can able to wipe all your private data. This data and tracking information will be stored in one central web server database and one can access it anytime through login.
文摘High availability is a critical mission for business system. At first, an instance of business system OPENSTOCK for pharmacy is introduced including both client and server sides. Secondly, a solution to the high availability of this system is given in detail, including design and implementation. The essentiality of this solution consists of scope of system information, system parameter tables of service status, schedule strategies of load ba lance and how to acquire system parameters and detect service states. The solution proposed is scalable and application oriented and supporting load balance for high performance and fault tolerate for high reliability. This application system has been applied and verified realistically, and the features of this business system derived in this paper have been achieved.
文摘While the market potentials and impacts of web-based e-commerce are still in the ascendant, the advances in wireless technologies and mobile networks have brought about a new business opportunity and research attention, what is termed mobile commerce. Commonly, mobile commerce is considered to be another new application of existing web-based e-commerce onto wireless networks, but as an independent business area, mobile commerce has its own advantages and challenges as opposed to traditional e-commerce applications. This paper focuses on exploring the unique features of mobile commerce as compared with traditional e-commerce. Also, there are still some limitations arisen in m-commerce in contrast to web-based e-commerce. Finally, current state of mobile commerce in Japan is presented in brief, with an introduction of several cases involving mobile commerce applications in today's marketplace.
基金supported by the Natural Science Foundation of China (71103021, 71573022, 71372193, 71301106)Beijing Philosophy and Social Science Planning Foundation (13JGC085)+1 种基金Beijing Higher Education Yong Elite Teacher Foundation (YETP0852)Humanities and Social Sciences Foundation of the Ministry of Education(13YJC630034, 13YJA790023)
文摘Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only for avoiding redundant e-government IS development but also for improving collaboration among government agencies. Two research questions were explored: what are the factors influencing the performance of SEIS? Will mandatory SEIS create a better performance than non-mandatory SEIS? Specifically, the use of five categories of IS aspects--information system quality, online service quality, offline service quality, diffusion modes and standard network size—is proposed to understand the performance of SEIS through applying both survey study and simulation study. The results show that information system quality and online service quality of SEIS have strong effects on users' expectation and users' satisfaction, which thereafter promotes the performance of SEIS. Government agencies' offline service quality shows a significant effect on users' satisfaction while not on users' expectation. Furthermore, the diffusion speed of SEIS in non-mandatory and mandatory modes and the standard network size also have great influence on the utility of SEIS.
基金Supported by the National Key Research and Development Program of China(2018YFA0606302 and 2012CB955900)
文摘In the context of global warming,China is facing with increasing climate risks.It is imperative to develop quantitative indices to reflect the climate risks caused by extreme weather/climate events and adverse climatic conditions in association with different industries.Based on the observations at 2288 meteorological stations in China and the meteorological disasters data,a set of indices are developed to measure climate risks due to water-logging,drought,high temperature,cryogenic freezing,and typhoon.A statistical method is then used to construct an overall climate risk index(CRI)for China from these individual indices.There is a good correspondence between these indices and historical climatic conditions.The CRI,the index of water-logging by rain,and the high temperature index increase at a rate of 0.28,0.37,and 0.65 per decade,respectively,from 1961 to 2016.The cryogenic freezing index is closely related to changes in the consumer price index for food.The high temperature index is correlated with the consumption of energy and electricity.The correlation between the yearly growth in claims on household property insurance and the sum of the water-logging index and the typhoon index in the same year is as high as 0.70.Both the growth rate of claims on agricultural insurance and the annual growth rate of hospital inpatients are positively correlated with the CRI.The year-on-year growth in the number of domestic tourists is significantly negatively correlated with the CRI in the same year.More efforts are needed to develop regional CRIs.
基金This work is supported by the National Science and Technology Major Project of China(No.2016ZX03001025-003)Special Fund for Beijing Common Construction Project.
文摘In recent years,IoV(Internet of Vehicles)has become one of the most active research elds in network and intelligent transportation system.As an open converged network,IoV plays an important role in solving various driving and traffc problems by advanced information and communications technology.We review the existing notions of IoV from di erent perspectives.Then,we provide our notion from a network point of view and propose a novel IoV architecture with four layers.Particularly,a novel layer named coordinative computing control layer is separated from the application layer.The novel layer is used for solving the coordinative computing and control problems for human-vehicle-environment.After summarizing the key technologies in IoV architecture,we construct a VV(Virtual Vehicle),which is an integrated image of driver and vehicle in networks.VVs can interact with each other in cyber space by providing traffc service and sharing sensing data coordinately,which can solve the communication bottleneck in physical space.Finally,an extended IoV architecture based on VVs is proposed.
文摘Point of interest(POI)recommendation is one of the most important tasks in location-based social networks(LBSN).The existing recommendation methods face two challenges:(1)the cold start problem caused by data sparsity;(2)underutilization of the abundant side information besides user-POI interaction in large-scale data.Recent research shows that a user’s social relationship can be used to solve the cold start problem to some extent.The deep neural network learns users’long term and short term preferences to improve the recommendation quality.Therefore,this paper proposes a POI recommendation model called SSANet,applying side information(S)and self-attention(SA)to provide the high-satisfaction POI recommendations for users.Specifically,first,the user-POI interaction matrix were constructed by users history data to represents the user hidden representation;second,the side information includes rating scores,access frequency,social relationship,and geographic information were used to extract users preference;third,we use self-attention mechanism to learn user long term and short term preference.The experimental results on the real LBSN datasets show that the recommendation performance of the SSANet model is better than the existing POI recommendation model.