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Toward Data-Driven Digital Therapeutics Analytics:Literature Review and Research Directions 被引量:1
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作者 Uichin Lee Gyuwon Jung +5 位作者 Eun-Yeol Ma Jin San Kim Heepyung Kim Jumabek Alikhanov Youngtae Noh Heeyoung Kim 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期42-66,共25页
With the advent of digital therapeutics(DTx),the development of software as a medical device(SaMD)for mobile and wearable devices has gained significant attention in recent years.Existing DTx evaluations,such as rando... With the advent of digital therapeutics(DTx),the development of software as a medical device(SaMD)for mobile and wearable devices has gained significant attention in recent years.Existing DTx evaluations,such as randomized clinical trials,mostly focus on verifying the effectiveness of DTx products.To acquire a deeper understanding of DTx engagement and behavioral adherence,beyond efficacy,a large amount of contextual and interaction data from mobile and wearable devices during field deployment would be required for analysis.In this work,the overall flow of the data-driven DTx analytics is reviewed to help researchers and practitioners to explore DTx datasets,to investigate contextual patterns associated with DTx usage,and to establish the(causal)relationship between DTx engagement and behavioral adherence.This review of the key components of datadriven analytics provides novel research directions in the analysis of mobile sensor and interaction datasets,which helps to iteratively improve the receptivity of existing DTx. 展开更多
关键词 Causal inference data-driven analytics framework digital therapeutics(DTx) mobile and wearable data technical and behavioral engagement
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Protecting Data Mobility in Cloud Networks Using Metadata Security
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作者 R.Punithavathi M.Kowsigan +3 位作者 R.Shanthakumari Miodrag Zivkovic Nebojsa Bacanin Marko Sarac 《Computer Systems Science & Engineering》 SCIE EI 2022年第7期105-120,共16页
At present,health care applications,government services,and banking applications use big data with cloud storage to process and implement data.Data mobility in cloud environments uses protection protocols and algorith... At present,health care applications,government services,and banking applications use big data with cloud storage to process and implement data.Data mobility in cloud environments uses protection protocols and algorithms to secure sensitive user data.Sometimes,data may have highly sensitive information,lead-ing users to consider using big data and cloud processing regardless of whether they are secured are not.Threats to sensitive data in cloud systems produce high risks,and existing security methods do not provide enough security to sensitive user data in cloud and big data environments.At present,several security solu-tions support cloud systems.Some of them include Hadoop Distributed File Sys-tem(HDFS)baseline Kerberos security,socket layer-based HDFS security,and hybrid security systems,which have time complexity in providing security inter-actions.Thus,mobile data security algorithms are necessary in cloud environ-ments to avoid time risks in providing security.In our study,we propose a data mobility and security(DMoS)algorithm to provide security of data mobility in cloud environments.By analyzing metadata,data are classified as secured and open data based on their importance.Secured data are sensitive user data,whereas open data are open to the public.On the basis of data classification,secured data are applied to the DMoS algorithm to achieve high security in HDFS.The pro-posed approach is compared with the time complexity of three existing algo-rithms,and results are evaluated. 展开更多
关键词 data mobility data security cloud computing big data DMoS algorithm
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An Asynchronous Clustering and Mobile Data Gathering Schema Based on Timer Mechanism in Wireless Sensor Networks 被引量:8
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作者 Jin Wang Yu Gao +2 位作者 Wei Liu Wenbing Wu Se-Jung Lim 《Computers, Materials & Continua》 SCIE EI 2019年第3期711-725,共15页
Recently,Wireless sensor networks(WSNs)have become very popular research topics which are applied to many applications.They provide pervasive computing services and techniques in various potential applications for the... Recently,Wireless sensor networks(WSNs)have become very popular research topics which are applied to many applications.They provide pervasive computing services and techniques in various potential applications for the Internet of Things(IoT).An Asynchronous Clustering and Mobile Data Gathering based on Timer Mechanism(ACMDGTM)algorithm is proposed which would mitigate the problem of“hot spots”among sensors to enhance the lifetime of networks.The clustering process takes sensors’location and residual energy into consideration to elect suitable cluster heads.Furthermore,one mobile sink node is employed to access cluster heads in accordance with the data overflow time and moving time from cluster heads to itself.Related experimental results display that the presented method can avoid long distance communicate between sensor nodes.Furthermore,this algorithm reduces energy consumption effectively and improves package delivery rate. 展开更多
关键词 Internet of things wireless sensor networks CLUSTERING mobile data collection timer.
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Exploring Temporal Activity Patterns of Urban Areas Using Aggregated Network-driven Mobile Phone Data:A Case Study of Wuhu,China 被引量:3
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作者 ZHANG Shanqi YANG Yu +1 位作者 ZHEN Feng LOBSANG Tashi 《Chinese Geographical Science》 SCIE CSCD 2020年第4期695-709,共15页
The increasing availability of data in the urban context(e.g.,mobile phone,smart card and social media data)allows us to study urban dynamics at much finer temporal resolutions(e.g.,diurnal urban dynamics).Mobile phon... The increasing availability of data in the urban context(e.g.,mobile phone,smart card and social media data)allows us to study urban dynamics at much finer temporal resolutions(e.g.,diurnal urban dynamics).Mobile phone data,for instance,are found to be a useful data source for extracting diurnal human mobility patterns and for understanding urban dynamics.While previous studies often use call detail record(CDR)data,this study deploys aggregated network-driven mobile phone data that may reveal human mobility patterns more comprehensively and can mitigate some of the privacy concerns raised by mobile phone data usage.We first propose an analytical framework for characterizing and classifying urban areas based on their temporal activity patterns extracted from mobile phone data.Specifically,urban areas’diurnal spatiotemporal signatures of human mobility patterns are obtained through longitudinal mobile phone data.Urban areas are then classified based on the obtained signatures.The classification provides insights into city planning and development.Using the proposed framework,a case study was implemented in the city of Wuhu,China to understand its urban dynamics.The empirical study suggests that human activities in the city of Wuhu are highly concentrated at the Traffic Analysis Zone(TAZ)level.This large portion of local activities suggests that development and planning strategies that are different from those used by metropolitan Chinese cities should be applied in the city of Wuhu.This article concludes with discussions on several common challenges associated with using network-driven mobile phone data,which should be addressed in future studies. 展开更多
关键词 mobile phone data human mobility urban travel patterns prefectural-level Chinese city Wuhu
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CPFinder: Finding an unknown caller's profession from anonymized mobile phone data 被引量:1
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作者 Jiaquan Zhang Hui Chen +1 位作者 Xiaoming Yao Xiaoming Fu 《Digital Communications and Networks》 SCIE CSCD 2022年第3期324-332,共9页
Identifying an unfamiliar caller's profession is important to protect citizens' personal safety and property. Owing to the limited data protection of various popular online services in some countries, such as ... Identifying an unfamiliar caller's profession is important to protect citizens' personal safety and property. Owing to the limited data protection of various popular online services in some countries, such as taxi hailing and ordering takeouts, many users presently encounter an increasing number of phone calls from strangers. The situation may be aggravated when criminals pretend to be such service delivery staff, threatening the user individuals as well as the society. In addition, numerous people experience excessive digital marketing and fraudulent phone calls because of personal information leakage. However, previous works on malicious call detection only focused on binary classification, which does not work for the identification of multiple professions. We observed that web service requests issued from users' mobile phones might exhibit their application preferences, spatial and temporal patterns, and other profession-related information. This offers researchers and engineers a hint to identify unfamiliar callers. In fact, some previous works already leveraged raw data from mobile phones (which includes sensitive information) for personality studies. However, accessing users' mobile phone raw data may violate the more and more strict private data protection policies and regulations (e.g., General Data Protection Regulation). We observe that appropriate statistical methods can offer an effective means to eliminate private information and preserve personal characteristics, thus enabling the identification of the types of mobile phone callers without privacy concerns. In this paper, we develop CPFinder —- a system that exploits privacy-preserving mobile data to automatically identify callers who are divided into four categories of users: taxi drivers, delivery and takeouts staffs, telemarketers and fraudsters, and normal users (other professions). Our evaluation of an anonymized dataset of 1,282 users over a period of 3 months in Shanghai City shows that the CPFinder can achieve accuracies of more than 75.0% and 92.4% for multiclass and binary classifications, respectively. 展开更多
关键词 Mobile big data Profession prediction Machine learning CLASSIFICATION Privacy protection
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SDN-Based Data Offloading for 5G Mobile Networks 被引量:1
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作者 Mojdeh Amani Toktam Mahmoodi +1 位作者 Mallikarjun Tatipamula Hamid Aghvami 《ZTE Communications》 2014年第2期34-40,共7页
The rapid growth of 3G/4G enabled devices such as smartphones and tablets in large numbers has created increased demand for mobile data services. Wi-Fi offloading helps satisfy the requirements of data-rich applicatio... The rapid growth of 3G/4G enabled devices such as smartphones and tablets in large numbers has created increased demand for mobile data services. Wi-Fi offloading helps satisfy the requirements of data-rich applications and terminals with improved multi- media. Wi-Fi is an essential approach to alleviating mobile data traffic load on a cellular network because it provides extra capacity and improves overall performance. In this paper, we propose an integrated LTE/Wi-Fi architecture with software-defined networking (SDN) abstraction in mobile baekhaul and enhanced components that facilitate the move towards next-generation 5G mo- bile networks. Our proposed architecture enables programmable offloading policies that take into account real-time network conditions as well as the status of devices and applications. This mechanism improves overall network performance by deriving real- time policies and steering traffic between cellular and Wi-Fi networks more efficiently. 展开更多
关键词 mobile data offloading LTE/Wi-Fi interworking policy derivation network selection software-defined networking dynamic policies 5G mobile networks
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Energy-Efficient Mobile Data Collection Adopting Node Cooperation in an Underwater Acoustic Sensor Network
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作者 Yougan Chen Xiaoting Jin Xiaomei Xu 《China Communications》 SCIE CSCD 2017年第6期32-42,共11页
This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node ind... This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme. 展开更多
关键词 underwater acoustic sensor networks mobile data collection node cooperation cooperative communications energy efficiency
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Exploring relations between city regions based on mobile phone data
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作者 汪烁枫 李志恒 +1 位作者 姜山 谢娜 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1799-1806,共8页
City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations b... City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations between regions of Shanghai based on mobile phone data is explored. By formulating the regions as nodes in a network and the commuting between each pair of regions as link weights, the distribution of nodes degree, and spatial structures of communities in this relation network are studied. Statistics show that regions locate in urban centers and traffic hubs have significantly larger degrees. Moreover, two kinds of spatial structures of communities are found. In most communities, nodes are spatially neighboring. However, in the communities that cover traffic hubs, nodes often locate along corridors. 展开更多
关键词 mobile phone data city relations community DEGREE
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Advances in Mobile Data Communications
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作者 Sean Cai Li Mo ZTE ZTE USA an active member of IEEE,ITU,ETSI,and IETF 《ZTE Communications》 2011年第4期42-42,共1页
This special issue of ZTE Communications focuses on recent advances in mobile data communications for the ICT and telecommunications industries. The ever-increasing amount of mobile data traffic has beenthe subject of... This special issue of ZTE Communications focuses on recent advances in mobile data communications for the ICT and telecommunications industries. The ever-increasing amount of mobile data traffic has beenthe subject of many studies. This research area is widely applicable to contemporary technology and network optimization techniques. 展开更多
关键词 ZTE MIMO OFDMA Advances in Mobile data Communications
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Broadband Mobile Data Service Era is Coming
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作者 Zhang Zhijiang 《ZTE Communications》 2009年第1期1-3,共3页
For China’s telecom industry,2009 is destined to be an extraordinary year due to the approach of long-thirsted-for mobile 3G era,which will have significant impact on current work and lifestyles.2009 will also be a y... For China’s telecom industry,2009 is destined to be an extraordinary year due to the approach of long-thirsted-for mobile 3G era,which will have significant impact on current work and lifestyles.2009 will also be a year full of opportunities and challenges because the coming 3G era will bring limitless business opportunities and impose more challenges on Chinese telecom operators.The reshuffling of Chinese telecom markets has been brought to an end.The new China Unicom,China Mobile and China Telecom all focus their strategies on broadband mobile data services in order to achieve the objective of a smooth transforming from voice services to data services.Technologically,various 3G technologies and their evolutions become great concerns of telecom operators;while in terms of services,the key for 3G systems is their data services.As a result,high speed broadband data services see an era of rapid development. 展开更多
关键词 AS data Broadband Mobile data Service Era is Coming
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Understanding the spatiotemporal patterns of nighttime urban vibrancy in central Shanghai inferred from mobile phone data
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作者 ZHANG Yangfan ZHONG Weijing +1 位作者 WANG De LIN Feng-Tyan 《Regional Sustainability》 2021年第4期297-307,共11页
In recent years,major cities around the world such as New York in USA,Melbourne in Australia,and Shanghai in China,have planned to boost their nighttime urban vibrancy levels to spur the economy and achieve cultural d... In recent years,major cities around the world such as New York in USA,Melbourne in Australia,and Shanghai in China,have planned to boost their nighttime urban vibrancy levels to spur the economy and achieve cultural diversity.The study of nighttime urban vibrancy from the perspective of spatiotemporal characteristics is increasingly being recognized as part of the essential work in the field of urban planning and geography.This research used mobile phone signaling records to measure urban vibrancy in central Shanghai and revealed its spatiotemporal patterns during nighttime.Specifically,this research explored the changes of urban vibrancy within a day,studied the distribution of urban vibrancy during the nighttime,and visually presented the spatiotemporal changes of nighttime urban vibrancy in central Shanghai.Moreover,on the basis of the behavior pattern of each mobile user,we classified nighttime urban vibrancy into three different types:nighttime working vibrancy,nighttime leisure vibrancy,and nighttime floating vibrancy.We then tried to determine how land use affected nighttime leisure vibrancy.The results showed that urban vibrancy in central Shanghai exhibits a periodic pattern over one-day period.A high-level nighttime urban vibrancy belt is present within central Shanghai.Business offices,hotels,entertainment and recreational districts,wholesale markets,and express services contribute most to the vibrancy at nighttime.In addition,the correlation analysis shows that public and commercial facilities generate high levels of nighttime leisure vibrancy than residential facilities.The mixed land use of public and commercial facilities and residential facilities within 500 m is more critical than the mixed use of a single land lot.The research can be a basis for supporting land use planning and providing evidence for policy-making to improve the level of nighttime urban vibrancy in cities. 展开更多
关键词 Nighttime urban vibrancy Mobile phone data Land use Public and commercial facilities Residential facilities Central Shanghai
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Utilization of online systems to promote youth participation in research:A methodological study
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作者 Marie Salem Lance Pollack +1 位作者 Alex Zepeda Kathleen P Tebb 《World Journal of Methodology》 2023年第4期210-222,共13页
BACKGROUND Online surveys can align with youth’s increased use of the internet and can be a mechanism for expanding youth participation in research.This is particularly important during the coronavirus disease 2019(C... BACKGROUND Online surveys can align with youth’s increased use of the internet and can be a mechanism for expanding youth participation in research.This is particularly important during the coronavirus disease 2019(COVID-19)pandemic,when inperson interactions are limited.However,the advantages and drawbacks of online systems used for research need to be carefully considered before utilizing such methodologies.AIM To describe and discuss the strengths and limitations of an online system developed to recruit adolescent girls for a sexual health research study and conduct a three-month follow up survey.METHODS This methodology paper examines the use of an online system to recruit and follow participants three months after their medical visit to evaluate a mobile sexual and reproductive health application,Health-E You/Salud iTuTM,for adolescent girls attending school-based health centers(SBHCs)across the United States.SBHC staff gave adolescent girls a web link to an online eligibility and consent survey.Participants were then asked to complete two online surveys(baseline and 3-month follow-up).Surveys,reminders,and incentives to complete them were distributed through short message service(SMS)text messages.Upon completing each survey,participants were also sent an email with a link to an electronic gift card as a thank-you for their participation.Barriers to implementing this system were discussed with clinicians and staff at each participating SBHC.RESULTS This online recruitment and retention system enabled participant recruitment at 26 different SBHCs in seven states across the United States.Between September 2021 and June 2022,415 adolescent girls were screened using the Qualtrics online survey platform,and 182 were eligible to participate.Of those eligible,78.0%(n=142)completed the baseline survey.Participants were racially,geographically,and linguistically diverse.Most of the participants(89.4%)were non-White,and 40.8%spoke Spanish.A total of 62.0%(n=88)completed the 3-month follow-up survey.Limitations of this system included reliance on internet access(via Wi-Fi or cell service),which was not universally available or reliable.In addition,an individual unrelated to the study obtained the survey link,filled out multiple surveys,and received multiple gift cards before the research team discovered and stopped this activity.As a result,additional security protocols were instituted.CONCLUSION Online systems for health research can increase the reach and diversity of study participants,reduce costs for research personnel time and travel,allow for continued study operation when in-person visits are limited(such as during the COVID-19 pandemic),and connect youth with research using technology.However,there are challenges and limitations to online systems,which include limited internet access,intermittent internet connection,data security concerns,and the potential for fraudulent users.These challenges should be considered prior to using online systems for research. 展开更多
关键词 Online recruitment Adolescents Sexual and reproductive health Mobile data Methodology paper data security
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Empowering smart city situational awareness via big mobile data
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作者 Zhiguang SHAN Lei SHI +3 位作者 Bo LI Yanqiang ZHANG Xiatian ZHANG Wei CHEN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2024年第2期286-307,共22页
Smart city situational awareness has recently emerged as a hot topic in research societies,industries,and governments because of its potential to integrate cutting-edge information technology and solve urgent challeng... Smart city situational awareness has recently emerged as a hot topic in research societies,industries,and governments because of its potential to integrate cutting-edge information technology and solve urgent challenges that modern cities face.For example,in the latest five-year plan,the Chinese government has highlighted the demand to empower smart city management with new technologies such as big data and Internet of Things,for which situational awareness is normally the crucial first step.While traditional static surveillance data on cities have been available for decades,this review reports a type of relatively new yet highly important urban data source,i.e.,the big mobile data collected by devices with various levels of mobility representing the movement and distribution of public and private agents in the city.We especially focus on smart city situational awareness enabled by synthesizing the localization of hundreds of thousands of mobile software Apps using the Global Positioning System(GPS).This technique enjoys advantages such as a large penetration rate(∼50%urban population covered),uniform spatiotemporal coverage,and high localization precision.We first discuss the pragmatic requirements for smart city situational awareness and the challenges faced.Then we introduce two suites of empowering technologies that help fulfill the requirements of(1)cybersecurity insurance for smart cities and(2)spatiotemporal modeling and visualization for situational awareness,both via big mobile data.The main contributions of this review lie in the description of a comprehensive technological framework for smart city situational awareness and the demonstration of its feasibility via real-world applications. 展开更多
关键词 Smart city Mobile data Situational awareness
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A Throughput-Aware Joint Vehicle Route and Access Network Selection Approach Based on SMDP 被引量:3
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作者 Jiandong Xie Sa Xiao +2 位作者 Ying-Chang Liang Li Wang Jun Fang 《China Communications》 SCIE CSCD 2020年第5期243-265,共23页
In intelligent transportation system(ITS), the interworking of vehicular networks(VN) and cellular networks(CN) is proposed to provide high-data-rate services to vehicles. As the network access quality for CN and VN i... In intelligent transportation system(ITS), the interworking of vehicular networks(VN) and cellular networks(CN) is proposed to provide high-data-rate services to vehicles. As the network access quality for CN and VN is location related, mobile data offloading(MDO), which dynamically selects access networks for vehicles, should be considered with vehicle route planning to further improve the wireless data throughput of individual vehicles and to enhance the performance of the entire ITS. In this paper, we investigate joint MDO and route selection for an individual vehicle in a metropolitan scenario. We aim to improve the throughput of the target vehicle while guaranteeing its transportation efficiency requirements in terms of traveling time and distance. To achieve this objective, we first formulate the joint route and access network selection problem as a semi-Markov decision process(SMDP). Then we propose an optimal algorithm to calculate its optimal policy. To further reduce the computation complexity, we derive a suboptimal algorithm which reduces the action space. Simulation results demonstrate that the proposed optimal algorithm significantly outperforms the existing work in total throughput and the late arrival ratio.Moreover, the heuristic algorithm is able to substantially reduce the computation time with only slight performance degradation. 展开更多
关键词 mobile data offloading network selection route selection semi-Markov decision process vehicular network
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uSensing:a Universal Platform to Support Smartphones Accessing Wireless Sensor Networks
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作者 He Nengqiang Jiang Chunxiao +2 位作者 Dong Yuhan Ren Yong Chen Canfeng 《China Communications》 SCIE CSCD 2012年第4期99-109,共11页
This paper presents a universal platform "uSensing" to support smartphones to communicate with sensor nodes in Wireless Sensor Networks (WSNs).Since phones have different CPU processers and operating systems... This paper presents a universal platform "uSensing" to support smartphones to communicate with sensor nodes in Wireless Sensor Networks (WSNs).Since phones have different CPU processers and operating systems,it is a challenge to merge these heterogeneities and develop such a universal platform.In this paper,we design both hardware and software to support the "universal" feature of uSensing:1) "uSD" card:an IEEE 802.15.4 physical communication card with SD interface;2) "uSinkWare":a WSNs middleware running on smartphones.Integrated with uSD card and uSinkWare,phones become mobile data sinks to access into WSNs and parse messages from sensor nodes.We demonstrate the proposed uSensing platform in a commercial smartphone to connect with our WSNs testbed,and validate that the smartphone has the same WSNs functions as commercial fixed sink.Additionally,we evaluate the performance of uSensing platform through measuring phone's CPU load and power consumption,and analyze the performance of these metrics theoretically.The results suggest that the phone-based mobile sink has enough capability to serve as a mobile sink of WSNs and can work up to twenty hours due to low power consumption. 展开更多
关键词 WSNS universal platform SMARTPHONE mobile data sink
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V2V Online Data Offloading Method Based on Vehicle Mobility
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作者 Xianlang Hu Dafang Zhang +2 位作者 Shizhao Zhao Guangsheng Feng Hongwu Lv 《国际计算机前沿大会会议论文集》 2020年第1期44-60,共17页
As people are accustomed to getting information in the vehicles,mobile data offloading through Vehicular Ad Hoc Networks(VANETs)becomes prevalent nowadays.However,the impacts caused by the vehicle mobility(such as the... As people are accustomed to getting information in the vehicles,mobile data offloading through Vehicular Ad Hoc Networks(VANETs)becomes prevalent nowadays.However,the impacts caused by the vehicle mobility(such as the relative speed and direction between vehicles)have great effects on mobile data offloading.In this paper,a V2V online data offloading method is proposed based on vehicle mobility.In this mechanism,the network service process was divided into continuous and equal-sized time slots.Data were transmitted in a multicast manner for the sake of fairness.The data offloading problem was formalized to maximize the overall satisfaction of the vehicle users.In each time slot,a genetic algorithm was used to solve the maximizing problem to obtain a mobile data offloading strategy.And then,the performance of the algorithm was enhanced by improving the algorithm.The experiment results show that vehicle mobility has a great effect on mobile data offloading,and the mobile data offloading method proposed in the paper is effective. 展开更多
关键词 Vehicular Ad Hoc Networks Mobile data offloading Vehicle mobility Multicast manner Genetic algorithm
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Dynamic Assessment of Spatiotemporal Population Distribution Based on Mobile Phone Data: A Case Study in Xining City,China
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作者 Benyong Wei Guiwu Su Fenggui Liu 《International Journal of Disaster Risk Science》 SCIE CSCD 2023年第4期649-665,共17页
High-resolution,dynamic assessments of the spatiotemporal distributions of populations are critical for urban planning and disaster management.Mobile phone big data have real-time collection,wide coverage,and high res... High-resolution,dynamic assessments of the spatiotemporal distributions of populations are critical for urban planning and disaster management.Mobile phone big data have real-time collection,wide coverage,and high resolution advantages and can thus be used to characterize human activities and population distributions at fne spatiotemporal scales.Based on six days of mobile phone user-location signal(MPLS)data,we assessed the dynamic spatiotemporal distribution of the population of Xining City,Qinghai Province,China.The results show that strong temporal regularity exists in the daily activities of local residents.The spatiotemporal distribution of the local population showed a signifcant downtown-suburban attenuation pattern.Factors such as land use types,holidays,and seasons signifcantly afect the spatiotemporal patterns of the local population.By combining other spatiotemporal trajectory data,high-resolution and dynamic real-time population distribution evaluations based on mobile phone location signals could be better developed and improved for use in urban management and disaster assessment research. 展开更多
关键词 China High-resolution mobile phone data Spatiotemporal population distribution Urban management Xining City
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功能-要素-流视角下的乡村活力空间识别与评价——以中国杭州市临安区为例
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作者 张晶 管晨悦 +6 位作者 章琳 虞舟鲁 叶成煊 朱从谋 李思楠 王珂 干牧野 《Journal of Geographical Sciences》 SCIE CSCD 2024年第6期1228-1250,共23页
Rural vitality is the life force expressed by a combination of endogenous dynamics and external influences. Exploring the complex relationship between rural functions, elements and flows could achieve sustainable rura... Rural vitality is the life force expressed by a combination of endogenous dynamics and external influences. Exploring the complex relationship between rural functions, elements and flows could achieve sustainable rural development. This study constructed a theoretical framework guided by the four functions of production, living, ecology and culture with the support of mobile big data. Furthermore, the network centrality of villages was estimated to reflect the intensity of urban-rural social mobility ties. The results indicated marked spatial disparities in rural vitality, and the coupling of ecological-cultural vitality has a high degree of coherence. Four rural vitality grades were identified: high level(38, 14.08%), medium-high level(66, 24.44%), medium-low level(110, 40.74%) and low level(56, 20.74%), covering 270 administrative village units. The flow intensity of social linkage elements is consistent with rural vitality and the socioeconomic spillover effect of urban centers on neighboring villages was noticeable. Topographic complexity negatively affected the living function, mainly in the T1 and T2 terrain gradients;the rural ecological function was not fully correlated with urban adjacency, and proximity could lead to adverse effects such as urban sprawl and resource destruction. The application of this study is to explore the importance of “flow” by utilizing mobile big data to refine the evaluation unit to the village scale. Accelerating the construction of network coverage and information interconnection and promoting the elemental flow of people, transportation and information between urban and rural areas are important ways to enhance rural vitality. 展开更多
关键词 rural vitality rural multifunction ELEMENTS urban-rural flows mobile big data
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Database Research: Achievements and Challenges 被引量:4
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作者 王珊 杜小勇 +1 位作者 孟小峰 陈红 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第5期823-837,共15页
Database system is the infrastructure of the modern information system. The R&D in the database system and its technologies is one of the important research topics in the field. The database R&D in China took off la... Database system is the infrastructure of the modern information system. The R&D in the database system and its technologies is one of the important research topics in the field. The database R&D in China took off later but it moves along by giant steps. This report presents the achievements Renmin University of China (RUC) has made in the past 25 years and at the same time addresses some of the research projects we, RUC, are currently working on. The National Natural Science Foundation of China supports and initiates most of our research projects and these successfully conducted projects have produced fruitful results. 展开更多
关键词 database management system parallel database systems Chinese database systems self-managing databases P2P computing and databases data warehousing OLAP Web data management XML mobile data management semantic web contextual information retrieval
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Population distribution modelling at fine spatio-temporal scale based on mobile phone data 被引量:1
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作者 Petr Kubicek Milan Konecny +6 位作者 Zdenek Stachon Jie Shen Lukas Herman Tomas Reznik Karel Stanek Radim Stampach Simon Leitgeb 《International Journal of Digital Earth》 SCIE EI 2019年第11期1319-1340,共22页
Population distribution modelling can benefit many different domains,for example,transportation,urban planning,ecology or emergency management.Information about the location and number of people in an affected area is... Population distribution modelling can benefit many different domains,for example,transportation,urban planning,ecology or emergency management.Information about the location and number of people in an affected area is crucial for decision-makers during emergencies and crises.Mobile phone data represents relatively reliable and time accurate information on real-time population distribution,movement and behaviour.In this study,we evaluate the spatio-temporal distribution of population derived from phone data of the selected pilot area(City of Brno,Czech Republic).Analysis is based on the dataset describing the estimated human presence(EHP)with two values-visitors and transiting persons.The temporal change of data is first analysed and further processed using two methodological approaches.First,the dasymetric method is used where the building geometry and technical attributes served as a target layer.Second,the results of building level analysis are transformed into a regular grid zone of both visitors and the general EHP.Resulting spatio-temporal patterns are compared to the census data.Results demonstrate how the proposed building level dasymetric approach can improve the spatial granularity of EHP.Potential use of proposed methodology within selected emergency situations is further discussed. 展开更多
关键词 Population distribution modelling mobile phone data estimated human presence emergency management
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