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张洪程院士讲授《如何生产好稻米》——江苏为农服务网“视频诊断”平台迎来第100期节目
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《农家致富》 2017年第10期9-9,共1页
自2015年以来,江苏为农服务网“视频诊断”平台“问诊”节目邀请来自农业部门、高校、科研单位的80多位专家走进直播室,讲授“三新”技术,推介致富项目,解析发展对策,创新远程诊断服务,为专家和农户搭建了可视互动平台。
关键词 直播室 科研单 农业部门 远程诊断 稻作 浏览量 服位 长江流域
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土耳其的纤维工业和纺织工业
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作者 蔡俊惠 《纺织导报》 CAS 1990年第3期12-12,共1页
纤维生产能力增加 1980年以来,土耳其化学纤维产量增加了两倍,在西欧排在第4位(1980年为第7位),居联邦德国、意大利、西班牙之后。 合成纤维占总产量的97%,其中以短纤维(聚酯、丙烯腈系纤维、聚丙烯纤维)为主,长丝以涤纶和尼纶6... 纤维生产能力增加 1980年以来,土耳其化学纤维产量增加了两倍,在西欧排在第4位(1980年为第7位),居联邦德国、意大利、西班牙之后。 合成纤维占总产量的97%,其中以短纤维(聚酯、丙烯腈系纤维、聚丙烯纤维)为主,长丝以涤纶和尼纶6为主。 至1989年底,合成纤维年生产能力为36.6万吨.西欧只有联邦德国和意大利才具有较大的生产能力。 纺织纤维消耗量增加 根据Werner的预测,到2000年土耳其纺织纤维消耗量将超过56万吨(每人消耗量为8.6公斤),而棉纱和羊毛的消耗量将下降,消耗量增加的主要部份是合成纤维。 展开更多
关键词 纤维工业 纤维产量 尼纶 丙烯腈系纤维 Werner 进口国家 环锭纺纱机 八十年代 服位 剑杆织机
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On the Experience, Problems in Science and Technology Services of Basic Scientific Research Institutes and Suggestions——Taking Zhenjiang Institute of Agricultural Sciences in Hilly Areas of Jiangsu as an Example
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作者 王敬根 单延博 +1 位作者 曲直 刘照亭 《Agricultural Science & Technology》 CAS 2017年第12期2681-2683,2686,共4页
Taking the Jiangsu Province as Zhenjiang Academy of Agricultural Sciences in Hilly Areas of an example, the paper elaborated the advanced practices of agricultural research institutes in agricultural science and techn... Taking the Jiangsu Province as Zhenjiang Academy of Agricultural Sciences in Hilly Areas of an example, the paper elaborated the advanced practices of agricultural research institutes in agricultural science and technology services and analyzed the difficulties and solutions in the services. process of science and technologyservices. 展开更多
关键词 Basic scientific research institutes Science and technology services EXPERIENCE Existing problems SOLUTIONS
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ANALYSIS ON A TYPE OF SERVICING MACHINES MODEL WITH REPAIRABLE SERVICE STATION
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作者 朱翼隽 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第2期153-159,共7页
This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantiti... This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained. 展开更多
关键词 queuing theory DISTRIBUTION Erlangian distribution repairable service station cyclic time inefficiency quantities
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虞姬为何嫁项羽
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《湖南教育(上旬)(A)》 1989年第Z1期80-80,共1页
人们熟悉《霸王别姬》中的虞姬,但很少有人知道她嫁给项羽的故事。相传虞姬原名丽姬,住在今江苏省苏州市平江路仓街丽姬巷。她才华出众,姿色倾城,惹得附近的小伙子纷纷托媒向她求婚。可是丽姬对那些平庸的青年一个都看不上,便托辞说:“
关键词 丽姬 才华出众 《霸王别姬》 仓街 都怒 庙前 服位 徐起 伸舌
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Precision Point to Point Control of Proportional Valve Controlled Motor with a Time Varying Load
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作者 彭熙伟 王渝 王向周 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期288-293,共6页
Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the ti... Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the time? varying deadzone and gain. Methods The large positioning errors caused by the time varying deadzone were significantly reduced by using the dynamic compensation method for the deadzone; and the large overshoot caused by the time varying gain were dramatically reduced by using the three section intelligent control schemes. Results Experimental results demonstrated that the positioning performance of rapid response, high accuracy and smaller or even no overshoot was achieved under a wide variations of load torque. Conclusion The good positioning performance for valve controlled motor servo systems has been achieved in the presence of the time varying deadzone and gain. 展开更多
关键词 fuzzy control intelligent control deadzone compensation point to point control electrohydraulic proportional servo system
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Location and Its Semantics in Location-Based Services 被引量:1
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作者 ZHAO Dongqing LUE Zhiping ZHANG Xiguang 《Geo-Spatial Information Science》 2007年第2期145-150,共6页
Starting with a simple presentation of location determination techniques, physical location and geographic location as two common kinds of location description methods are discussed. The semantic location concept is t... Starting with a simple presentation of location determination techniques, physical location and geographic location as two common kinds of location description methods are discussed. The semantic location concept is then introduced and a correction is given, which especially emphasizes that location property is an important part of semantic location. By analyzing the connotation and extension of every geographic location, what should be contained in a location property is determined. Using a hierarchical model, the relations and associations among locations are clearly described. To realize a formalized description of semantic location, an ontology technique that can adequately describe semantic information of location is used. Organized by ontology web language, a location ontology model allows semantic location to be read and processed by computer. The location ontology model realizes the knowledge description of location information and establishes an important foundation to personalized preference services in location based services. 展开更多
关键词 personalized preference services LOCATION SEMANTICS ONTOLOGY
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Situation and Development Tendency of Indoor Positioning 被引量:81
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作者 邓中亮 余彦培 +2 位作者 袁协 万能 杨磊 《China Communications》 SCIE CSCD 2013年第3期42-55,共14页
This paper introduces the significance of indoor positioning and analyzes the related problems. The latest research on indoor positioning is introduced. Further, the positioning accuracy and the cost of typical local ... This paper introduces the significance of indoor positioning and analyzes the related problems. The latest research on indoor positioning is introduced. Further, the positioning accuracy and the cost of typical local and wide area indoor positioning systems are compared. The results of the comparison show that Time & Code Division-Orthogonal Frequency Division Multiplexing (TC-OFDM) is a system that can achieve real-time meter-accuracy of indoor positioning in a wide area. Finally, in this paper, we indicate that the seamless high-accuracy indoor positioning in a wide area is the development trend of indoor positioning. The seamless Location Based Services (LBS) architecture based on a heterogeneous network, key technologies in indoor positioning for decimeter-accuracy and seamless outdoor and indoor Geographic Information System (GIS) are elaborated as the most important research fields of future indoor positioning. 展开更多
关键词 indoor positioning LBS REVIEW wide area local area TC-OFDM
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An RSSl Gradient-based AP Localization Algorithm 被引量:4
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作者 ZHAO Fang LUO Haiyong +1 位作者 GENG Hao SUN Qijin 《China Communications》 SCIE CSCD 2014年第2期100-108,共9页
Recent rapid rise of indoor location based services for smartphones has further increased the importance of precise localization of Wi-Fi Access Point(AP).However,most existing AP localization algorithms either exhibi... Recent rapid rise of indoor location based services for smartphones has further increased the importance of precise localization of Wi-Fi Access Point(AP).However,most existing AP localization algorithms either exhibit high errors or need specialized hardware in practical scenarios.In this paper,we propose a novel RSSI gradient-based AP localization algorithm.It consists of the following three major steps:firstly,it uses the local received signal strength variations to estimate the direction(minus gradient) of AP,then employs a direction clustering method to identify and filter measurement outliers,and finally adopts triangulation method to localize AP with the selected gradient directions.Experimental results demonstrate that the average localization error of our proposed algorithm is less than 2meters,far outperforming that of the weighted centroid approach. 展开更多
关键词 AP localization RSSI gradient CLUSTERING TRIANGULATION
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Influence of impurities on damping properties of ZK60 magnesium alloy 被引量:2
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作者 陈先华 毛建军 +2 位作者 潘复生 彭建 王敬丰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第7期1305-1310,共6页
The influence of impurities on damping capacities of ZK60 magnesium alloys in the as-cast,as-extruded and T4-treated states was investigated by dynamically mechanical analyzer at room temperature.Granato and Lucke dis... The influence of impurities on damping capacities of ZK60 magnesium alloys in the as-cast,as-extruded and T4-treated states was investigated by dynamically mechanical analyzer at room temperature.Granato and Lucke dislocation pinning model was employed to explain damping properties of the alloys.It is found that reducing impurity content can decrease the amount of second-phase particles,increase grain size and improve damping capacity of the as-cast alloy slightly.The as-extruded alloy with lower impurity content is found to possess obviously higher damping capacity in the relatively high strain region than that with higher impurity concentration,which appears to originate mainly from different dislocation characteristics.The variation tendency of damping property with change of impurity content after solution-treatment is also similar to that in the as-extruded and as-cast states. Meanwhile,the purification of the alloy results in an evident improvement in tensile yield strength in the as-extruded state. 展开更多
关键词 ZK60 magnesium alloy IMPURITIES DAMPING DISLOCATION
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Privacy-Preserving Relative Location Based Services for Mobile Users 被引量:4
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作者 Fei Ning Zhuang Yi +2 位作者 GU Jingjing Cao Jiannong Yang Liang 《China Communications》 SCIE CSCD 2015年第5期152-161,共10页
Location-aware applications have been used widely with the assistance of the latest positioning features in Smart Phone such as GPS,AGPS,etc.However,all the existing applications gather users' geographical data an... Location-aware applications have been used widely with the assistance of the latest positioning features in Smart Phone such as GPS,AGPS,etc.However,all the existing applications gather users' geographical data and transfer them into the pertinent information to give meaning and value.For this kind of solutions,the user's privacy and security issues might be raised because the geographical location has to be exposed to the service provider.A novel and practical solution is proposed in this article to provide the relative location of two mobile users based on their WiFi scanned results without any additional sensors.There is no privacy concern in this solution because end users will not collect and send any sensitive information to the server.This solution adopts a Client/Server(C/S) architecture,where the mobile user as a client reports the ambient WiFi APs and the server calculates the distances based on the WiFi AP's topological relationships.A series of technologies are explored to improve the accuracy of the estimated distance and the corresponding algorithms are proposed.We also prove the feasibility with the prototype of "Circle Your Friends" System(CYFS) on Android phone which lets the mobile user know the distance between him and his social network friends. 展开更多
关键词 relative location privacy-preserv-ing CYFS
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Interval Type-2 fuzzy position control of electro-hydraulic actuated robotic excavator 被引量:3
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作者 Hassan Mohammed Yousif Kothapalli Ganesh 《International Journal of Mining Science and Technology》 SCIE EI 2012年第3期437-445,共9页
This paper deals with fuzzy intelligent position control of electro-hydraulic activated robotic excavator for the control of boom, arm and bucket axes. Intelligent control systems are required to overcome unde- sirabl... This paper deals with fuzzy intelligent position control of electro-hydraulic activated robotic excavator for the control of boom, arm and bucket axes. Intelligent control systems are required to overcome unde- sirable stick-slip motion, limit cycles and oscillations. Models of electro-hydraulic servo controlled front end loader excavators are highly nonlinear. The nonlinear model accounts for fluid flow rate of valve, pump hydraulics, and friction forces. The friction forces are modelled by Coulomb, viscous and Stribeck function. Interval Type-2 Fuzzy Logic Controller (IT2FLC) is used to study the time-domain position responses of axes in the presence of external applied load. It has the ability to control the position of each of the three axes with minimum actuator position errors. Models presented are accurate and study the dynamics of the actuator and load. To improve the transient behaviour of the robotic excavator, we elim- inated iitter of the bucket movement in the presence of nonlinearities. 展开更多
关键词 ExcavatorFuzzy controlMiningRobotType-2
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Achieve Personalized Anonymity Through Query Blocks Exchanging 被引量:13
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作者 Chunguang Ma Lei Zhang +2 位作者 Songtao Yang Xiaodong Zheng Pinhui Ke 《China Communications》 SCIE CSCD 2016年第11期106-118,共13页
In cyberspace security,the privacy in location-based services(LBSs) becomes more critical. In previous solutions,a trusted third party(TTP) was usually employed to provide disturbance or obfuscation,but it may become ... In cyberspace security,the privacy in location-based services(LBSs) becomes more critical. In previous solutions,a trusted third party(TTP) was usually employed to provide disturbance or obfuscation,but it may become the single point of failure or service bottleneck. In order to cope with this drawback,we focus on another important class,establishing anonymous group through short-range communication to achieve k-anonymity with collaborative users. Along with the analysis of existing algorithms,we found users in the group must share the same maximum anonymity degree,and they could not ease the process of preservation in a lower one. To cope with this problem,we proposed a random-QBE algorithm to put up with personalized anonymity in user collaboration algorithms,and this algorithm could preserve both query privacy and location privacy. Then we studied the attacks from passive and active adversaries and used entropy to measure user's privacy level. Finally,experimental evaluations further verify its effectiveness and efficiency. 展开更多
关键词 cyberspace security location-based services collaborative users personalized anonymity query and location privacy
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Amplitude phase control for electro-hydraulic servo system based on normalized least-mean-square adaptive filtering algorithm 被引量:4
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作者 姚建均 富威 +1 位作者 胡胜海 韩俊伟 《Journal of Central South University》 SCIE EI CAS 2011年第3期755-759,共5页
The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorit... The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorithm.The command input was corrected by weights to generate the desired input for the algorithm,and the feedback was brought into the feedback correction,whose output was the weighted feedback.The weights of the normalized LMS adaptive filtering algorithm were updated on-line according to the estimation error between the desired input and the weighted feedback.Thus,the updated weights were copied to the input correction.The estimation error was forced to zero by the normalized LMS adaptive filtering algorithm such that the weighted feedback was equal to the desired input,making the feedback track the command.The above concept was used as a basis for the development of amplitude phase control.The method has good real-time performance without estimating the system model.The simulation and experiment results show that the proposed amplitude phase control can efficiently cancel the amplitude attenuation and phase delay with high precision. 展开更多
关键词 amplitude attenuation phase delay normalized least-mean-square adaptive filtering algorithm tracking performance electro- hydraulic servo system
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Improvement of Dynamic and Steady Characteristics of Pneumatic Position Servo with Fuzzy-PI Control
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作者 杨功军 赵彤 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期57+53-57,共6页
This paper provided a fuzzy-PI control. It makes use of the advantages of fuzzy controller for dynamic characteristics, and the advantages of PI control for steady characteristics of pneumatic position servo. Experime... This paper provided a fuzzy-PI control. It makes use of the advantages of fuzzy controller for dynamic characteristics, and the advantages of PI control for steady characteristics of pneumatic position servo. Experimental results show that positioning accuracy meets the conventional industrial needs, and prove that the fuzzy-PI controller to be correct and more effective than the usual PID controller. The control method improve the dynamic and steady characteristics of the system. 展开更多
关键词 non-linear control system fuzzy control/pneumatic position servo fuzzy-PI control
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Control strategy for pneumatic rotary position servo systems based on feed forward compensation pole-placement self-tuning method 被引量:2
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作者 毛新涛 杨庆俊 +1 位作者 吴晋军 包钢 《Journal of Central South University》 SCIE EI CAS 2009年第4期608-613,共6页
The pneumatic rotary position system, in which an electro-pneumatic proportional flow valve controled a rotary cylinder, was studied, and its mathematical model was built. The model indicated that the controlled pneum... The pneumatic rotary position system, in which an electro-pneumatic proportional flow valve controled a rotary cylinder, was studied, and its mathematical model was built. The model indicated that the controlled pneumatic system had disadvantages such as inherent non-linearity and variations of system parameters with working points. In order to improve the dynamic performance of the system, feed forward compensation self-tuning pole-placement strategy was adopted to place the poles of the system in a desired position in real time, and a recursive least square method with fixed forgetting factors was also used in the parameter estimation. Experimental results show that the steady state error of the pneumatic rotary position system is within 3% and the identified system parameters can be converged in 5 s. Under different loads, the controlled system has an excellent tracking performance and robustness of anti-disturbance. 展开更多
关键词 pneumatic servo system adaptive control parameter identification POLE-PLACEMENT
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Wireless location technology and its application 被引量:2
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作者 Zhao Junhui Wang Dongming 《Engineering Sciences》 EI 2011年第4期32-37,共6页
Wireless location technology is used to locate,track and monitor the location of given target using devices such as the radio frequency identification(RFID) based on WiFi technology and the sensors. And such applicati... Wireless location technology is used to locate,track and monitor the location of given target using devices such as the radio frequency identification(RFID) based on WiFi technology and the sensors. And such applications as long term evolution(LTE) ,wireless local area networks(WLAN) ,RFID and location based service(LBS) are essential in today's wireless communications industry. In this paper,both wireless location technology and its application are proposed,where our experimental research results and theoretical innovation are included. 展开更多
关键词 wireless location technology APPLICATION LTE WLAN RFID LBS
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Driving properties of plane wire-driven robot 被引量:3
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作者 王克义 张立勋 孟浩 《Journal of Central South University》 SCIE EI CAS 2013年第1期56-61,共6页
A three-DOF (degree of freedom) planar robot completely restrained and positioned parallel pulled by four wires was studied. The wire driving properties were analyzed through experiments. The restrained three-DOF plan... A three-DOF (degree of freedom) planar robot completely restrained and positioned parallel pulled by four wires was studied. The wire driving properties were analyzed through experiments. The restrained three-DOF planar platform was established based on slippery course and bearing, and dSPACE real-time control system was used to perform the platform's motion control experiment on robot. Based on the kinematic equation and mechanical balance equation of moving platform, the stiffness of the robot system was analyzed and the calibration scheme of the system considering wire tension was put forward. Position servo control experiments were carried out, position servo tracking precision was analyzed, and real-time wire tension was detected. The results show that the moving error of the moving platform tracking is small (the maximum difference is about 3%), and the rotation error is large (the maximum difference is about 12%). The wire tension has wave properties (the wire tension fluctuation is about 10 N). 展开更多
关键词 wire driven robot driving properties CALIBRATION position control
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A Location Privacy Preserving Solution to Resist Passive and Active Attacks in VANET 被引量:2
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作者 ZHU Xiaoling HU Donghui HOU Zhengfeng DING Liang 《China Communications》 SCIE CSCD 2014年第9期60-67,共8页
Existing location privacy- preserving methods, without a trusted third party, cannot resist conspiracy attacks and active attacks. This paper proposes a novel solution for location based service (LBS) in vehicular a... Existing location privacy- preserving methods, without a trusted third party, cannot resist conspiracy attacks and active attacks. This paper proposes a novel solution for location based service (LBS) in vehicular ad hoc network (VANET). Firstly, the relationship among anonymity degree, expected company area and vehicle density is discussed. Then, a companion set F is set up by k neighbor vehicles. Based on secure multi-party computation, each vehicle in V can compute the centroid, not revealing its location to each other. The centroid as a cloaking location is sent to LBS provider (P) and P returns a point of interest (POI). Due to a distributed secret sharing structure, P cannot obtain the positions of non-complicity vehicles by colluding with multiple internal vehicles. To detect fake data from dishonest vehicles, zero knowledge proof is adopted. Comparing with other related methods, our solution can resist passive and active attacks from internal and external nodes. It provides strong privacy protection for LBS in VANET. 展开更多
关键词 vehicular ad hoc network locationbased services location k-anonymity securemulti-party computation
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Pseudo-Location Updating System for Privacy-Preserving Location-Based Services
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作者 牛犇 朱晓妍 +1 位作者 池浩田 李晖 《China Communications》 SCIE CSCD 2013年第9期1-12,共12页
With the rapid development of location-aware devices such as smart phones,Location-Based Services(LBSs) are becoming increasingly popular. Users can enjoy convenience by sending queries to LBS servers and obtaining se... With the rapid development of location-aware devices such as smart phones,Location-Based Services(LBSs) are becoming increasingly popular. Users can enjoy convenience by sending queries to LBS servers and obtaining service information that is nearby.However, these queries may leak the users' locations and interests to the un-trusted LBS servers, leading to serious privacy concerns. In this paper, we propose a Privacy-Preserving Pseudo-Location Updating System(3PLUS) to achieve k-anonymity for mobile users using LBSs. In 3PLUS, without relying on a third party, each user keeps pseudo-locations obtained from both the history locations and the encountered users, and randomly exchanges one of them with others when encounters occur. As a result, each user's buffer is disordered. A user can obtain any k locations from the buffer to achieve k-anonymity locally. The security analysis shows the security properties and our evaluation results indicate that the user's privacy is significantly improved. 展开更多
关键词 pseudo-location K-ANONYMITY pri-vacy LBS
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