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1.
用户驱动的微博可视化搜索   总被引:1,自引:1,他引:0       下载免费PDF全文
目的 微博作为一个社交与信息分享平台,日信息量数以亿计,如何高效地搜索用户感兴趣的信息成为亟待解决的问题.提出了一个新颖的用户驱动的可视化微博信息搜索方法.方法 采用特征词及其权重来建模用户的兴趣特征,并基于此建立用户与特征词之间的相关关系.搜索微博信息时,首先定位与检索词相关的微博用户,在相关微博用户的微博中筛选与搜索相关的微博.另外,采用关注度传递算法对搜索进行扩展,将返回的特征词和微博用户进行可视化展示,并提供交互供用户查看与选定特征词或用户相关的微博.结果 实验结果表明,基于本文方法,用户可以高效地定位感兴趣的微博信息.结论 以用户作为桥梁,大大缩小了微博信息的搜索范围,同时采用关注度传递算法对搜索进行扩展,对结果进行可视化展示.实验表明本文方法能够使用户快速搜索出感兴趣的信息.  相似文献   

2.
RFID localization algorithms and applications—a review   总被引:1,自引:0,他引:1  
Object localization based on radio frequency identification (RFID) technology has promising potentials. By combining localization with its identification capability, existing applications can be enhanced and new applications can be developed for this technology. This paper starts with an overview introducing the available technologies for localization with a focus on radio frequency based technologies. The existing and potential applications of RFID localization in various industries are then summarized. Moreover, RFID localization algorithms are reviewed, which can be categorized into multilateration, Bayesian inference, nearest-neighbor, proximity, and kernel-based learning methods. Also, we present a localization case study using passive RFID technology, and it shows that objects can be successfully localized using either multilateration or Bayesian inference methods. The survey also discusses the challenges and future research on RFID localization.  相似文献   

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The article provides views from researchers and practitioners directly involved with robotics applications to find out what they think about the applicability of this new generation of more adaptable and user-friendly robots. Aspects discussed include: personal robots in human societies; robot teams in urban search and rescue; space robots and natural language communication; representation and reasoning; and rationality and emotions.  相似文献   

5.
Many large retailers decided to adopt RFID as their new supply chain technology, but RFID adoption by all industries did not spread as rapidly as initially expected. We believe that its benefits constituted the major barrier to its adoption, and argued that a major contributor to the delay has been its inappropriate implementation. Our study reports the result of six in-depth case studies, which, together with case content analysis of 88 reported RFID applications, provided us with a clear view of the RFID implementation landscape, suggesting that organizations often mindlessly adopted RFID applications that were misaligned with their supply chain strategies, leading to unsatisfactory benefits. Insights into how organizations should adopt RFID were developed from our results and were discussed.  相似文献   

6.
A compact, robust, chipless radio frequency identification (RFID) tag is proposed. Resonant elements patterned in a concentric fashion encode data in the spectral domain employing frequency shift encoding. The proposed tag encodes 28.25 data bits over a miniscule physical footprint of 25 × 25 mm2. The formulated scheme is demonstrated to be viable for encoding of temporal variables. The electromagnetic performance of the presented design is investigated for different laminates: Rogers RT/duroid® 5880 and Taconic TLX‐0. Multiple tag prototypes employing a variety of substrates are realized and evaluated for in‐laboratory performance. The proposed design is compared with existing work reported in literature. Code density of 4.52 bits/cm2 has been successfully achieved. The tag design operates from 3.07 to 10.6 GHz and is readily realizable on flexible laminates. Smart retail, intelligent packaging, adaptive ticketing, and similar time‐related applications can be materialized using the proposed tag.  相似文献   

7.
This article proposes an equilateral triangule‐shaped patch antenna for radio frequency identification (RFID) applications in the 900 MHz (902–928 MHz) ultra high frequency (UHF) band. To achieve optimal impedance matching and 10‐dB operating bandwidth at the desired band, the L‐shaped probe‐feed technique was used as the feeding structure of the proposed antenna. Furthermore, a near semicircular notch was also loaded into the patch so that good circularly polarized (CP) radiation can be generated from the proposed patch antenna. By simply shifting the position or radius of this notch, the CP frequency can be varied with ease. Here, 10‐dB impedance bandwidth and 3‐dB axial ratio bandwidth of 25 and 3% were achieved. Furthermore, stable gain variation of approximately 6 dBi was also exhibited across the RFID UHF band. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:580–586, 2014.  相似文献   

8.
Tactile interfaces are used to communicate information through the sense of touch, which is an area of growing interest in the research community. Potential applications include virtual training for surgeons, remotely touching materials via the Internet, automotive industry, active interfaces for blind persons, and sensory substitution devices.  相似文献   

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多视频摘要技术近年来受到了国内外学者的广泛关注,它是指通过对视频结构和内容的分析,从多个相关视频文件中提取出有意义的部分,将它们以一定方式进行组合,形成简洁的、能够充分表现语义内容的概要,目的是提供快捷的浏览和查询服务。目前该技术还处于起步阶段,实际的应用系统很少,有关体系结构、技术方法仍需要深入研究,更多的应用方向还有待开拓。在介绍研究意义的基础上,对多视频摘要的研究现状和主要方法进行了归纳、评述,探讨了一些应用方向,指出了目前研究面临的重点问题以及发展趋势。  相似文献   

10.
In coming years, there will be billions of RFID tags living in the world tagging almost everything for tracking and identification purposes. This phenomenon will impose a new challenge not only to the network capacity but also to the scalability of event processing of RFID applications. Since most RFID applications are time sensitive, we propose a notion of Time To Live (TTL), representing the period of time that an RFID event can legally live in an RFID data management system, to manage various temporal event patterns. TTL is critical in the “Internet of Things” for handling a tremendous amount of partial event-tracking results. Also, TTL can be used to provide prompt responses to time-critical events so that the RFID data streams can be handled timely. We divide TTL into four categories according to the general event-handling patterns. Moreover, to extract event sequence from an unordered event stream correctly and handle TTL constrained event sequence effectively, we design a new data structure, namely Double Level Sequence Instance List (DLSIList), to record intermediate stages of event sequences. On the basis of this, an RFID data management system, namely Temporal Management System over RFID data streams (TMS-RFID), has been developed. This system can be constructed as a stand-alone middleware component to manage temporal event patterns. We demonstrate the effectiveness of TMS-RFID on extracting complex temporal event patterns through a detailed performance study using a range of high-speed data streams and various queries. The results show that TMS-RFID has a very high throughput, namely 170,000–870,000 events per second for different highly complex continuous queries. Moreover, the experiments also show that the main structure to record the intermediate stages in TMS-RFID does not increase exponentially with the number of events. These results demonstrate that TMS-RFID not only supports high processing speeds, but is also highly scalable.  相似文献   

11.
RFID systems have been widely adopted in various industrial as well as personal applications. However, traditional RFID systems are limited to address only one tag for each application object. This limitation hinders the usability of RFID applications because it is difficult, if not impossible, to distinguish many tags simultaneously with existing RFID systems. In this paper, we propose a new RFID tag structure to support multiple-objects that can be easily shared by many different RFID applications. That is, the proposed RFID tag structure supports that a tag maintains several different objects and allows those applications to access them simultaneously. We also propose an authentication protocol to support multiple-object RFID applications. Especially, we focus on the efficiency of the authentication protocol by considering different security levels in RFID applications. The proposed protocol includes two types of authentication procedures. In the proposed protocol, an object has its security level and goes through one of different authentication procedures suitable for its security level. We report the results of a simulation to test the performance of the proposed scheme. In our simulation, we considered the safety of our scheme against potential attacks and evaluated the efficiency of the proposed protocol.  相似文献   

12.

Modern scientific research challenges require new technologies, integrated tools, reusable and complex experiments in distributed computing infrastructures. But above all, computing power for efficient data processing and analyzing. Containers technologies have emerged as a new paradigm to address such intensive scientific applications problems. Their easy deployment in a reasonable amount of time and the few required computational resource make them more suitable. Containers are considered light virtualization solutions. They enable performance isolation and flexible deployment of complex, parallel, and high-performance systems. Moreover, they gained popularity to modernize and migrate scientific applications in computing infrastructure management. Additionally, they reduce computational time processing. In this paper, we first give an overview of virtualization and containerization technologies. We discuss the taxonomies of containerization technologies of the literature, and then we provide a new one that covers and completes those proposed in the literature. We identify the most important application domains of containerization and their technological progress. Furthermore, we discuss the performance metrics used in most containerization techniques. Finally, we point out research gaps in the related aspects of containerization technology that require more research.

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13.
When decision support systems are implemented in practice, a number of special aspects and requirements must often be considered. From an operations research (OR) perspective many of these can be very challenging and/or are counterproductive for the stated objective. They can appear in any part of the optimization process that includes problem formulation, modelling, solution and result evaluation. In this paper, we describe and discuss a number of aspects and requirements in industrial implementations where optimization has been a vital planning or execution tool. We discuss the reasons behind the requirements, the OR challenge, how the requirements were approached and implemented and present results and general experience acquired from these implementations. The applications cover tactical, operational and real‐time applications for several areas including transportation, scheduling, routing, inventory and process control.  相似文献   

14.
Is it possible to create a cloak of invisibility - a flexible artifact that can make anything inside it invisible and preserve invisibility despite mobility and deformation? Exploring the algorithmic and technological challenges involved reveals tantalizing information.  相似文献   

15.
介绍了基于嵌入式Linux用户自己编写的设备驱动程序的设计方法。把数组当作一个字符设备,设计了字符设备驱动程序的框架,并编写了设备驱动程序的测试程序,较完整的实现用户自己编写Linux设备驱动程序的思想。驱动程序的编写简洁明了,在HHARM9-EDU的实验平台上通过。有一定的实际应用价值。  相似文献   

16.
ObjectiveThe overall objective of the research work presented in this paper is to investigate models, methods and architectures to replace fixed, pre-packaged applications with flexible composition environments that make interactive environments “emerge” at run-time, based on composition actions performed by non-technical users. The approach aims at the lightweight construction of integrated, situational workspaces pervasively accessible and sharable through a variety of devices.MethodsBased on a meta-design approach, we designed and implemented a platform that allows end users, not necessarily experts of technologies, to extract contents from heterogeneous sources and compose Personal Information Spaces (PISs) that satisfy their information needs. Specific emphasis is posed on the adoption of a composition paradigm that abstracts from technical details and can thus be used by non-technical users.ResultsThe platform for service composition that supports the activity of the different involved stakeholders is described in details. Thanks to the separation of concerns on which the composition paradigm is based, the overall approach and its enabling platform are also amenable to customization with respect to the requirements of specific domains.ConclusionWe present an approach where a composition platform enables the extraction of content from heterogeneous services and its integration into situational applications where content presentation is flexibly managed through different visual templates. We also discuss the advantages offered by this approach to the stakeholders of a specific community of users in the Cultural Heritage domain.PracticeThe developed prototypes were evaluated in laboratories and field studies: the former aimed at investigating the ease of use and the users satisfaction of the functionality and the user interface of the environment for domain customization, the latter aimed instead at observing real users (e.g., guides of an archeological park) in action, to assess the validity of the proposed composition paradigm as an EUD practice.ImplicationsThe user studies described in this paper provided hints for refining the prototypes, and laid the basis for future work related to the identification of design principles that can make service-based composition technologies in general more useful and usable for end users.  相似文献   

17.
The use of RFID middleware to support application development for and integration of RFID hardware into information systems has become quite common in RFID applications where reader devices remain stationary, which currently represents the largest part of all RFID applications in use. Another field for applying RFID technology which is offering a huge set of novel possibilities and applications are mobile applications, where readers are no longer fixed. In order to address the specific issues of mobile RFID-enabled applications and to support developers in rapid application development, we present ID-Services, an architecture for an RFID middleware that is designed to support mobile applications. The ID-Services approach has been used to implement MoVIS (Mobile Visitor Information System), a mobile application which allows museum visitors to request individually adapted multimedia information about exhibits in an intuitive way.  相似文献   

18.
A novel dual‐band antenna for radio frequency identification tag is proposed for ultra high frequency (UHF: 915 MHz) and super high frequency (SHF: 2450 MHz) bands. The proposed tag antenna is a single sided dual‐antenna structure, designed on the grounded (metallic) dielectric substrate. The proposed tag antenna can be used on any kind of surfaces including metals without severe performance degradation due to its metallic ground plane. At UHF band, proposed tag antenna works as dual‐antenna structure. In the dual‐antenna structure, one antenna works for receiving and another for backscattering. Due to separate backscatterer, the maximum differential radar cross section improved and results in the enhancement of the maximum read range. Whereas at SHF band, proposed antenna works as conventional single antenna structure and during operations it switches between receiving and backscattering modes. The proposed antenna consists of a meandered line antenna and a rectangular patch antenna loaded with an F‐shaped and an inverted L‐shaped slots. The S‐parameters are measured by means of differential probe technique. Simulated and measured results are observed in good agreement. The read range is observed about 5 and 6 m at 915 and 2450 MHz, respectively. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:640–650, 2016.  相似文献   

19.
In the upcoming 5G and beyond systems,ultra-reliable and low latency communication(URLLC)has been considered as the key enabler to support diverse mission-criti...  相似文献   

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