面向RFID应用的情境感知计算关键技术研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
计算技术、通信技术、传感技术等新科技的飞速发展,使物联网(The Internet of Things)正在成为现实。射频识别技术(Radio Frequency Identification,RFID)作为物联网的重要支撑技术,受到了广泛关注。以高速发展的RFID技术及其产业化为核心,推广其在物流与供应链、交通、医疗卫生乃至更广阔领域的应用,是打造无所不在的物联网的必然途径。当前RFID应用存在的问题是自动化、智能化程度较低,并没有将RFID技术的潜能完全发挥出来。这一问题存在的深层次原因为:(1)缺乏对RFID应用中各种信息进行有效表示的模型;(2)现有RFID信息不确定性推理模型的表达能力有限,推理准确性有待进一步提高;(3)缺乏对RFID数据进行高层处理的框架。
     构建情境感知的RFID应用,对解决现有RFID应用在自动化和智能化等方面的不足将起着一定积极作用。RFID技术作为感知情境的主要手段之一,实时感知环境中出现的对象并对其进行跟踪;情境感知计算则将环境中各个对象(计算设备、用户、机器、物等对象)以及物理环境自身智能地连接起来,实现信息的实时扩展,通过信息融合、信息推理使得环境中的各个对象具有了认知能力,并可以根据这些信息进行交流、活动,最终实现机器与机器之间的“对话”,物与物之间的“对话”,最大限度地减少业务操作中的人工干预,提升自动化、智能化水平。为了实现面向RFID应用的情境感知计算,本文从以下几个方面进行了研究讨论:
     (1)定义了RFID应用中的情境信息,针对其特点,对面向RFID应用的情境模型的表达能力、可验证能力、可扩展能力、存储与查询效率等方面提出了要求。根据这几方面的要求,对六类情境模型的适用性进行比较,通过实验进行分析验证。最终得出面向对象的情境模型是适用于RFID应用的情境建模机制,并以物流与供应链领域中的RFID应用为例进行了建模。所建立的模型能够清晰的表达实体关系、时序信息,支持信息的验证与扩展,通过Hibernate技术可以实现情境信息的快速存储与查询。
     (2)针对已有对象追踪追溯不确定性推理方法的不足,提出了面向RFID应用的基于隐半马尔可夫模型的追踪追溯不确定性情境推理方法。提供的对象追踪追溯推理包括对象当前位置解释、对象将来位置预测以及确定最佳位置序列等。构建的隐半马尔可夫模型具有更强的表达力,能够表达对象在各位置的驻留时间概率,能够表达对象在某一位置驻留时间为固定长度的情况等。通过实验证明了具有更强表达力的基于隐半马尔可夫模型的情境推理方法比基于隐马尔可夫模型的情境推理方法具有更高的推理准确性,更适合于对RFID应用中的不确定性情境进行推理。
     (3)阐述了面向RFID应用的情境感知服务框架的设计理念。根据设计理念的要求,提出了用于建立面向RFID应用的情境感知服务框架的可配置、可重构组件模型,总结了基于该组件模型进行系统开发的流程。提出了面向RFID应用的情境感知服务框架的体系结构,并进行了系统实现。通过实验证明了采用所提出的组件模型并不会对系统的性能有较大影响。这一情境感知服务框架与其它已有的情境感知服务框架的不同之处在于:它是面向RFID应用的;它是与现有的RFID体系框架兼容的;它具有灵活性、扩展性、布署时可配置、运行时可重构的特点。
     (4)在以上工作的基础上,设计和开发了一个情境感知的应用—智能销售环境。描述了该智能销售环境中的区域划分、设备部署以及所实现的主动情境感知与被动情境感知;并通过该应用检验了面向RFID应用的情境感知服务框架的各项特征,充分体现了使用情境感知计算后给RFID应用所带来的自动性、智能性、实时性方面的好处。
With the rapid development of computing, communication and sensing technologies, the internet of things is on the way to become a reality. As a key technology of the internet of things, RFID attracts a lot of attentions. Focusing on RFID technology, its industrialization and promoting RFID’s applications in logistics and supply chain, transportation, health care and other industries is the only way to construct a pervasive internet of things. However, the automation and intelligence of applications is limited and the potential of RFID technology has not been fully tapped. The underlying reasons of the problem being: (1) Lack of an effective model to describe different kinds of information in RFID application; (2) Existing probabilistic inference models for RFID data processing is limited in expression and inference accuracy; (3) Lack of a framework to transform low level RFID data to high level.
     Construction of context-aware RFID applications will play an active role in solving the above mentioned problems. RFID technology is used to sense context, track and trace objects. Context-aware computing combines objects with physical environment intelligently. It provides information collection, fusion and inference so that each object in the environment is capable of cognition. They can communicate with each other and take proper actions, which will minimize human interference and promote automation and intelligence in RFID applications.To realize RFID oriented context aware computing, we undertook the following research:
     (1) Define context information in RFID application, and analyse its characteristics. The model should be expressive, verifiable and extensible. After comparison of existing models, we conclude that object-oriented context model is more suitable for modeling context information in RFID application. We use the object-oriented approach to model context information in RFID applications for logistics and supply chain management.
     (2) Present the necessity of probabilistic inference in RFID application. After the analysis of the shortcomings of the existing object tracking and tracing probabilistic inference methods, we put forward a hidden semi-Markov model based probabilistic inference model for RFID applications. Experiments done have proved that the proposed model performs best compared to the others.
     (3) Describe the design principles of the context-aware framework for RFID applications. Then we propose a service-oriented component-based configurable and reconfigurable model, the development lifecycle for the model and a workload balance mechanism to fulfill the design principles. On the basis of the component model, we designed and developed a context-aware framework for RFID applications. Different from existing frameworks, it is for RFID applications, compatible with existing RFID frameworks, flexible, extensible, deploytime configurable and run-time reconfigurable.
     (4) We also designed and developed a context-aware application– intelligent retailing environment. Through the application, we discuss the characteristics of the framework, proving that introducing context-aware computing into RFID application will result in considerable benefits.
引文
[1] Angeles, R. RFID technologies: Supply-chain applications and implementation issues [J]. Information Systems Management. 2005, Winter:51-65.
    [2] Attaran, M. RFID: An enabler of supply chain operations [J]. Supply Chain Management: An International Journal. 2007, 12(4):249-257.
    [3] Asif, Z., Mandviwalla, M. Integrating the supply chain with RFID: A technical and business analysis [J]. Communications of Association for Information Systems. 2005, 15(24):1-57.
    [4] Ren, Z., Gao, Y. Design of electronic toll collection system in expressway based on RFID. In Proceedings of 2009 International Conference on Environmental Science and Information Application Technology. 2009, 3:779-782.
    [5] Hornby, R.M. RFID solutions for the express parcel and airline baggage industry. IEE Colloquium on RFID Technology. 1999:1-5.
    [6] Vergara, A., Llobet, E., Ramírez, J.L., Ivanov, P., Fonseca, L., Zampolli, S., Scorzoni, A., Becker, T., Marco, S., Wollenstein, J. An RFID reader with onboard sensing capability for monitoring fruit quality [J]. Sensors & Actuators: B. Chemical. 2007, 127(1):143-149.
    [7] Rieback, M.R., Crispo, B., Tanenbaum, A.S. Is your cat infected with a computer virus? In Proceedings of the 4th Annual IEEE International Conference on Pervasive Computing and Communications. 2006:170-179.
    [8] Tu, J.Y., Zhou, W., Piramuthu, S. Identifying RFID-embedded objects in pervasive healthcare applications [J]. Decision Support Systems. 2009, 46(2):586-593.
    [9] ?ztaysi, B., Baysan, S., Akpinar, F. RFID in hospitality [J]. Technovation. 2009, 29(9):618-624.
    [10] Huang, G.Q., Zhang, Y.F., Jiang, P.Y. RFID-based wireless manufacturing for walking-worker assembly islands with fixed-position layouts [J]. Robotics and Computer-Integrated Manufacturing. 2007, 23(4): 469-477.
    [11] Boss, R.W. RFID technology for libraries. Library Technology Reports. 2003:1-19.
    [12] Choi, J.W., Oh, D.L., Song, I.Y. R-LIM: An affordable library search system based on RFID. In Proceedings of the 2006 International Conference on Hybrid Information Technology. 2006:103-108.
    [13] Wu, N.C., Nystrom, M.A., Lin, T.R., Yu, H.C. Challenges to global RFID adoption [J]. Technovation. 2006, 26(12):1317-1323.
    [14] Becker, J., Vilkov, L., Weiβ, B., Winkelmann, A. A model based approach for calculating the process driven business value of RFID investments [J]. International Journal of Production Economics. In press.
    [15] Véronneau, S., Roy, J. RFID benefits, costs, and possibilities: The economical analysis of RFID deployment in a cruise corporation global service supply chain [J]. International Journal of Production Economics. In Press.
    [16] Tajima, M. Strategic value of RFID in supply chain management [J]. Journal of Purchasing and Supply Management. 2007, 13(4):261-273.
    [17] Roh, J.J., Kunnathur, A., Tarafdar, M. Classification of RFID adoption: An expected benefits approach [J]. Information & Management. 2009, 46(6):357-363.
    [18] Tzeng, S.F., Chen, W.H., Pai, F.Y. Evaluating the business value of RFID: Evidence from five case studies [J]. International Journal of Production Economics. 2008, 112(2):601-613.
    [19] Bendavid, Y., Wamba, S.F., Lefebvre, L.A. Proof of concept of an RFID-enabled supply chain in a B2B e-commerce environment. In Proceedings of the 8th International Conference on Electronic Commerce. 2006:564-568.
    [20] Hewlett-Packard (HP). RFID in the supply chain: A balanced view. White paper.
    [21] Bottani, E., Rizzi, A. Economical assessment of the impact of RFID technology and EPC system on the fast-moving consumer goods supply chain [J]. International Journal of Production Economics. 2008, 112(2): 548-569.
    [22] Domdouzis, K., Kumar, B., Anumba, C. RFID applications: A brief introduction [J]. Advanced Engineering Informatics. 2007, 21(4):350-355.
    [23] Qiu, R.G. RFID-enabled automation in support of factory integration [J]. Robotics and Computer-Integrated Manufacturing. 2007, 23(6):677-683.
    [24] Inaba, T. Value of sparse RFID traceability information in asset tracking during migration period. In Proceedings of 2008 IEEE International Conference on RFID. 2008:183-190.
    [25] Campagna, M.J. RFID systems and methods for probabilistic location determination. United States Patent, Patent No.: US 7,388,494 B2. 2008.
    [26] Cambridge University, BT Research, SAP Research. Serial-level inventory tracking model. 2007.
    [27] Schilit, B.N., Adams, N., Want, R. Context-aware computing applications. In Proceedings of the 1st International Workshop on Mobile Computing Systems and Applications. 1994:85-90.
    [28] Dey, A.K., Abowd, G.D. Towards a better understanding of context and context awareness. GVU Technical Report GIT-GVU-99-22, GVU Center, College of Computing, Georgia Institute of Technology. 1999:304-307.
    [29]沈宇超,沈树群.射频识别技术及其发展现状.电子技术应用. 1999, 25(1):4-5.
    [30] Harrison, M. EPC information service - Data model and queries. Technical Report, Auto-ID center, 2003.
    [31] Harrison, M., Brusey, J., Moran, H., McFarlane, D. PML server developments. Technical Report, Auto-ID center, October 2003.
    [32] Want, R., Hopper, A., Falc?o, V., Gibbons, J. The active badge location system [J].ACM Transactions on Information Systems. 1992, 10(1):91-102.
    [33] Brooks, R.A. The intelligent room project. In Proceedings of the 2nd International Conference on Cognitive Technology. 1997:271-278.
    [34] Yan, H., Selker, T. Context-aware office assistant. In Proceedings of the 5th International Conference on Intelligent User Interfaces. 2000:276-279.
    [35] Fox, A., Johanson, B., Hanrahan, P., Winograd, T. Integrating information appliances into an interactive workspace [J]. Information Appliances. 2000, 20(3):54-65.
    [36] Kidd, C.D., Orr, R., Abowd, G.D., Atkeson, C.G., Essa, I.A., MacIntyre, B., Mynatt, E., Starner, T.E., Newstetter, W. The aware home: A living laboratory for ubiquitous computing research. In Proceedings of the 2nd International Workshop on Cooperative Buildings, Integrating Information, Organizations and Architecture. 1999:191-198.
    [37] Brumitt, B.L., Meyers, B., Krumm, J., Kern, A. EasyLiving: Technologies for intelligent environments. In Proceedings of International Symposium on Handheld and Ubiquitous Computing. 2000:12-27.
    [38] Mitchell, S., Spiteri, M., Bates, J., Coulouris, G. Context aware multimedia computing in the intelligent hospital. In Proceedings of the 9th ACM SIGOPS European Workshop. 2000:13-18.
    [39] Bardram, J. Applications of context-aware computing in hospital work-examples and design principles. In Proceedings of the 2004 ACM Symposium on Applied Computing. 2004:1574-1579.
    [40] Bardram, J. Hospitals of the future - ubiquitous computing support for medical work. In Proceedings of UbiHealth 2003 the 2nd International Workshop on Ubiquitous Computing for Pervasive Healthcare Applications. 2003.
    [41] Bardram, J., Bossen, C., Lykke-Olesen, A., Nielsen, R., Haslov Madsen, K. Virtual video prototyping of pervasive healthcare systems. In Proceedings of Symposium on Designing Interactive Systems. 2002:167–177.
    [42] Kjeldskov, J., Skov, M. Supporting work activities in healthcare by mobile electronic patient records. In Proceedings of the 6th Asia-Pacific Conference on Human-Computer Interaction. 2004:191-200.
    [43] Munoz, M., Rodriguez, M., Favela, J., Martinez-Garcia, A., Gonzalez, V. Context-aware mobile communication in hospitals [J]. IEEE Computing. 2003, 36(9):38–46.
    [44] Ko, E.J., Lee, H.J., Lee, J.W. Ontology-based context modeling and reasoning for U-healthcare [J]. IEICE Transactions on Information System. 2007, 90(8):1262-1270.
    [45] Strang, T., Linnhoff-popien, C. A context modeling survey. In Proceedings of the Workshop on Advanced Context Modelling, Reasoning and Management, the 6th International Conference on Ubiquitous Computing. 2004.
    [46] Dustdar, S., Rosenberg, F. A survey on context-aware systems [J]. International Journal on Ad Hoc and Ubiquitous Computing. 2007, 2(4):263-277.
    [47] Hong, J., Suh, E., Kim, S. Context-aware systems: A literature review and classification. Expert Systems with Applications. 2009, 36(4):8509-8522.
    [48] Samulowitz, M., Michahelles, F., Linnhoff-Popien, C. Capeus: An architecture for context-aware selection and execution of services. In Proceedings of the 3rd International Working Conference on Distributed Applications and Interoperable Systems. 2001:23-39.
    [49] Composite Capabilities/Preferences Profile. http://www.w3.org/Mobile/CCPP/
    [50] User agent profile specification. Wireless Application Group. 1999.
    [51] Sheng, Q.Z., Benatallah, B. ContextUML: A UML-based modeling language for model-driven development of context-aware web services. In Proceedings of the International Conference on Mobile Business. 2005:206-212.
    [52] Van den Bergh, J., Coninx, K. Towards modeling context-sensitive interactive applications: The context-sensitive user interface profile (CUP). In Proceedings of the2005 ACM Symposium on Software Visualization. 2005:87-94.
    [53] Derntl, M., Hummel, K.A. Modeling context-aware e-learning scenarios. In Proceedings of the 3rd IEEE International Conference on Pervasive Computing and Communications. 2005:337-342.
    [54] Henricksen, K., Indulska, J., Rakotonirainy, A. Modeling context information in pervasive computing systems. In Proceedings of the 1st International Conference on Pervasive Computing. 2002:167-180.
    [55] Hendricksen, K., Indulska, J., Rakotonirainy, A. Generating context management infrastructure from high-level context models. In Proceedings of the 4th International Conference on Mobile Data Management. 2003:1-6.
    [56] Schmidt, A., Van Laerhoven, K. How to build smart appliances? [J]. IEEE Personal Communications. 2001, 8(4):66-71
    [57] Hofer, T., Schwinger, W., Pichler, M., Leonhartsberger, G., Altmann, J. Context-awareness on mobile devices - the hydrogen approach. In Proceedings of the 36th Hawaii International Conference on System Science. 2003:1-10.
    [58] McCarthy, J. Notes on formalizing contexts. In Proceedings of the 13th International Joint Conference on Artificial Intelligence. 1993, 1: 555-560.
    [59] McCarthy, J., Buvac, S. Formalizing context (expanded notes). In Working Papers of the AAAI Fall Symposium on Context in Knowledge Representation and Natural Language. 1997.
    [60] Studer, R., Benjamins, V. R., Fensel, D. Knowledge engineering: Principles and methods [J]. Data and Knowledge Engineering. 1998, 25(1):161-197
    [61] ?tztürk, P., Aamodt, A. Towards a model of context for case-based diagnostic problem solving. In Proceedings of the Interdisciplinary Conference on Modeling and Using Context. 1997:198-208.
    [62] Chen, H., Finin, T., Joshi, A. Using OWL in a pervasive computing broker. InProceedings of Workshop on Ontologies in Open Agent Systems. 2003:9-16.
    [63] Chen, H., Finin, T., Joshi, A. An ontology for context-aware pervasive computing environments [J]. Special Issue on Ontologies for Distributed Systems. 2004,18(3):197-207.
    [64] Chen, H., Perich, F., Finin, T., Joshi, A. SOUPA: Standard ontology for ubiquitous and pervasive applications. In Proceedings of Mobile and Ubiquitous Systems: Networking and Services Conference. 2004:258-267.
    [65] Gu, T., Pung, H.K., Zhang, D.Q. A service-oriented middleware for building context-aware services [J]. Journal of Network and Computer Applications. 2005, 28(1):1-18.
    [66] Lin, X., Li, S., Yang, Z., Shi, W. Application-oriented context modeling and reasoning in pervasive computing. In Proceedings of the 5th International Conference on Computer and Information Technology. 2005:495-501.
    [67] Wang, X.H., Zhang, D.Q., Gu, T., Pung, H.K. Ontology based context modeling and reasoning using OWL. In Proceedings of the 2nd IEEE Conference on Pervasive Computing and Communications. 2004:18-22.
    [68]张庆生,齐勇,侯迪,赵季中.基于隐马尔科夫模型的上下文感知活动计算.西安交通大学学报. 2006, 40(4):398-401.
    [69] Korel, T.B., Koo, S.G.M. Addressing context awareness techniques in body sensor networks. In Proceedings of 21st International Conference on Advanced Information Networking and Applications Workshops. 2007:798-803.
    [70]慕春棣,戴剑彬,叶俊.用于数据挖掘的贝叶斯网络.软件学报. 2000, 11(5):660-666.
    [71] Ranganathan, A., Al-Muhtadi, J., Campbell, R.H. Reasoning about uncertain contexts in pervasive computing environments [J]. IEEE Pervasive Computing. 2004, 3(2):62-70.
    [72] Korpip??, P., M?ntyj?rvi, J., Kela, J., Ker?nen, H., Malm, E.J. Managing contextinformation in mobile devices [J]. IEEE Pervasive Computing. 2003, 2(3):42-51.
    [73]乔秀全,李晓峰,廖建新.业务上下文本体建模及不确定性推理.高技术通讯. 2007, 17(6):569-574.
    [74]乔秀全,李晓峰,廖建新.基于贝叶斯网络的业务上下文认知模型构建方法.电子与信息学报. 2008, 30(2): 464-467.
    [75] Dempster, A. Upper and lower probabilities induced by multivalued mapping [J]. Annals of Mathematical Statistics. 1967, 38(2): 325-339.
    [76] Shafer, G. A mathematical theory of evidence. Princeton: Princeton University Press, 1976.
    [77]张德干,徐光祐,史元春,赵海,陈恩义.面向普适计算的扩展的证据理论方法.计算机学报. 2004, 27(7):918-927.
    [78] Wu, H.D. Sensor data fusion for context-aware computing using dempster-shafer theory [Doctoral dissertation]. Pittsburgh, Pennsylvania: Carnegie Mellon University. 2003.
    [79] Jonsson, M., Werle, P., Jansson, C.G. Context shadow: An infrastructure for context aware computing. In Proceedings Artificial Intelligence in Mobile System. 2002.
    [80] Jonsson, M. Building extendable sensor infrastructures for pervasive computing environments. Technical Report 2002-019, Dept. of Computer and Systems Sciences, Stockholm University. 2002.
    [81] Werle, P., Kilander, F., Jonsson, M., L?nnqvist, P., Jansson, C.G. A ubiquitous service environment with active documents for teamwork support. In Proceedings of the Ubicomp 2001 Conference. 2001:139-155.
    [82] Dey, A.K. Context-aware computing: The CyberDesk project. In Proceedings of the 1998 Spring AAAI Symposium on Intelligent Environments, Technical Report SS-98-02. 1998:51-54.
    [83] Dey, A.K., Futakawa, M., Salber, D., Abowd, G.D. The conference assistant: Combining context-awareness with wearable computing. In Proceedings of the 3rdInternational Symposium on Wearable Computers. 1999:21-28.
    [84] Dey, A.K. Providing Architectural support for building context-aware applications [Doctoral Dissertation]. Georgia: Georgia Institute of Technology. 2000.
    [85] Dey, A.K. Understanding and using context [J]. Personal and Ubiquitous Computing. 2001, 5(1): 4-7.
    [86] Gu, T., Pung, H.K., Zhang, D.Q. Towards an OSGi-based infrastructure for context-aware applications in smart homes [J]. IEEE Pervasive Computing. 2004, 3(4):66-74.
    [87] Gu, T., Pung, H.K., Zhang, D.Q. A middleware for building context-aware mobile services. In Proceedings of IEEE Vehicular Technology Conference. 2004:2656-2660.
    [88] Gu, T., Wang, X.H., Pung, H.K., Zhang, D.Q. An ontology-based context model in intelligent environments. In Proceedings of Communication Networks and Distributed Systems Modeling and Simulation Conference. 2004:270-275.
    [89] Gu, T., Pung, H.K., Zhang, D.Q. A peer-to-peer overlay for context information search. In Proceedings of the 14th International Conference on Computer Communications and Networks. 2005:395-400.
    [90] Gu, T., Tan, E., Pung, H.K., Zhang, D.Q. A peer-to-peer architecture for context lookup. In Proceedings of the International Conference on Mobile and Ubiquitous Systems: Networking and Services. 2005:333-341.
    [91] Gu, T., Pung, H.K., Yao, J.K. Towards a flexible service discovery [J]. Journal of Network and Computer Applications. 2005, 28(3):233-248.
    [92] Román, M., Hess, C., Cerqueira, R., Ranganathan, A., Campbell, R.H., Nahrstedt, K. Gaia: A middleware infrastructure for active spaces [J]. IEEE Pervasive Computing, Special Issue on Wearable Computing. 2002:74-83
    [93] Román, M., Campbell, R.H. GAIA: Enabling active spaces. In proceedings of 9th ACM SIGOPS European Workshop. 2000:229-234.
    [94] Qin, W., Shi, Y., Suo, Y. Ontology-based context-aware middleware for smart spaces [J]. Tsinghua Science and Technology. 2007, 12(6):707-713.
    [95] Hibernate reference. https://www.hibernate.org/
    [96] OSGi reference. https://www.osgi.org/
    [97] Drools reference. http://labs.jboss.com/drools
    [98] EPCglobal. EPC information services standard (EPCIS), version 1.0.1. EPCglobal, Standards Specification. 2007.
    [99]贲可荣,张彦铎.人工智能.北京:清华大学出版社. 2006:142-145.
    [100] Russell, M.J., Moore, R.K. Explicit modeling of state occupancy in hidden Markov models for automatic speech recognition. In Proceedings of the 1985 IEEE International Conference on Acoustics, Speech and Signal Processing. 1985:5-8.
    [101] Guédon, Y. Estimation hidden semi-Markov chains from discrete sequences [J]. Journal of Computational and Graphical Statistics. 2003, 12(3):604-639.
    [102] Armenio, F., Barthel, H., Burstein, L., Dietrich, P., Duker, J., Garrett, J., Hogan, B., Ryaboy, O., Sarma, S., Schmidt, J., Suen, K., Traub, K., Williams, J. The EPCglobal architecture framework. 2007.
    [103] EPCglobal. Application level events (ALE) standard, version 1.1. EPCglobal, Standards Specification. 2008.
    [104] EPCglobal. Low level reader protocol (LLRP) standard, version 1.0.1. EPCglobal, Standards Specification. 2007.
    [105] EPCglobal. Reader protocol (RP) standard, version 1.1. EPCglobal, Standards Specification. 2006.
    [106] EPCglobal. Reader management (RM) standard, version 1.0.1. EPCglobal, Standards Specification. 2007.
    [107] EPCglobal. EPC tag data translation (TDT) standard, version 1.1. EPCglobal, Standards Specification. 2006.
    [108] EPCglobal. EPC tag data standard (TDS), version 1.4. EPCglobal, Standards Specification. 2008.
    [109] Chen, G., Kotz, D. A survey of context-aware mobile computing research. Dartmouth Computer Science Technical Report TR2000-381. 2000:1-16.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700