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排序方式: 共有698条查询结果,搜索用时 15 毫秒
81.
Kundu A. Bertino E. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2008,38(3):292-301
The paper proposes an approach to content dissemination that exploits the structural properties of an Extensible Markup Language (XML) document object model in order to provide an efficient dissemination and at the same time assuring content integrity and confidentiality. Our approach is based on the notion of encrypted postorder numbers that support the integrity and confidentiality requirements of XML content as well as facilitate efficient identification, extraction, and distribution of selected content portions. By using such notion, we develop a structure-based routing scheme that prevents information leaks in the XML data dissemination, and assures that content is delivered to users according to the access control policies, that is, policies specifying which users can receive which portions of the contents. Our proposed dissemination approach further enhances such structure-based, policy-based routing by combining it with multicast in order to achieve high efficiency in terms of bandwidth usage and speed of data delivery, thereby enhancing scalability. Our dissemination approach thus represents an efficient and secure mechanism for use in applications such as publish-subscribe systems for XML Documents. The publish-subscribe model restricts the consumer and document source information to the routers to which they register with. Our framework facilitates dissemination of contents with varying degrees of confidentiality and integrity requirements in a mix of trusted and untrusted networks, which is prevalent in current settings across enterprise networks and the Web. Also, it does not require the routers to be aware of any security policy in the sense that the routers do not need to implement any policy related to access control. 相似文献
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83.
Wireless Personal Communications - The paper reports the performance of an energy harvesting cognitive radio network under primary user emulation (PUE) attack. A secondary user (SU) can harvest... 相似文献
84.
Selvasundarasekar Sam Sankar Arumugam Rathishkumar Kathiresan Geetha Subrata Kundu 《International Journal of Hydrogen Energy》2021,46(17):10366-10376
Electrospinning (ES) is a most reliable method for synthesizing one dimensional (1D) fibrous material. Fibrous materials are having peculiar interest owing to their fascinating properties. For efficient hydrogen fuel generation, electrocatalytic water splitting is one of the finest way of producing hydrogen in a pure form. But it is encountered by the counter oxygen evolution reaction (OER) in more often. As of now, noble metal based catalysts are utilized in the commercial sector. Some of the disadvantages associated with the noble materials are restrict their usage commercially. To address this issue, herein, we have synthesized One dimensional (1D), hydrated porous cobalt phosphate fibrous network by an ES method and act as an electrocatalyst for OER in both alkaline and neutral media for the first time, which exhibits an overpotential of 245 and 457 mV respectively at a current density of 10 mAcm?2 with astonishing stability. 相似文献
85.
Mrinal Kanti Kundu Goutam Hatui Vineeta Nigam Arvind Kumar Saxena 《Polymer-Plastics Technology and Engineering》2015,54(7):691-702
A tubelike, naturally occurring halloysite clay mineral (HNTs) incorporated polyphosphazene (PPZ) elastomeric nanocomposites had been electron beam radiated and thermally treated for certain applications. To improve the dispersion of raw HNTs (H), an organosilane modifier had been exploited. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) technique were utilized for plausible interaction and intercalation. The efficiency of electron beam radiation over chemical initiation for intra and inter chain network formation within the resin was substantiated through oil and solvent resistance studies. Effective delay in mass transport as compared to the virgin elastomer was observed through thermal analysis. 相似文献
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87.
This paper proposes the development of water sample classification and authentication, in real life which is based on machine learning algorithms. The proposed techniques used experimental measurements from a pulse voltametry method which is based on an electronic tongue (E-tongue) instrumentation system with silver and platinum electrodes. E-tongue include arrays of solid state ion sensors, transducers even of different types, data collectors and data analysis tools, all oriented to the classification of liquid samples and authentication of unknown liquid samples. The time series signal and the corresponding raw data represent the measurement from a multi-sensor system. The E-tongue system, implemented in a laboratory environment for 6 numbers of different ISI (Bureau of Indian standard) certified water samples (Aquafina, Bisleri, Kingfisher, Oasis, Dolphin, and McDowell) was the data source for developing two types of machine learning algorithms like classification and regression. A water data set consisting of 6 numbers of sample classes containing 4402 numbers of features were considered. A PCA (principal component analysis) based classification and authentication tool was developed in this study as the machine learning component of the E-tongue system. A proposed partial least squares (PLS) based classifier, which was dedicated as well; to authenticate a specific category of water sample evolved out as an integral part of the E-tongue instrumentation system. The developed PCA and PLS based E-tongue system emancipated an overall encouraging authentication percentage accuracy with their excellent performances for the aforesaid categories of water samples. 相似文献
88.
In this paper, the impact of a multi slot based cooperative spectrum sensing (CSS) on the performance of a cognitive radio (CR) network has been investigated. Each CR user, equipped with an improved energy detector (IED), uses a number of mini slots of the sensing time to perform the spectrum sensing. Each CR uses OR logic to combine the sub local decisions generated in each mini slot to obtain a local decision at CR level. Local decisions are sent to fusion centre (FC) over reporting channel. The FC obtains a final decision about the presence of primary user (PU) by combining the local decisions using a fusion rule: Majority or Maximal Ratio Combining. The performance of the CSS is assessed in terms of detection probability and false alarm probability considering both the sensing and reporting channels are Rayleigh faded. Furthermore, the impact of a number of sensing slots and IED parameter on throughput of CR network is also evaluated under the proposed spectrum sensing scenario. Impacts of several sensing parameters such as sensing channel SNR and reporting channel SNR on the performance of CR network are also evaluated. Performances of two fusion rules under study are compared. Effect of sensing error and synchronisation error is indicated. Further the study is extended for independent but non identically distributed (i.n.i.d.) Rayleigh faded channels as well as for a multiple PU scenario also. 相似文献
89.
Microsystem Technologies - In this paper a new structure of MEMS based piezoelectric (PZ) energy harvester with resonant frequency of 100 Hz is proposed which can be integrated with... 相似文献
90.
Ghosh Manosij Kundu Tuhin Ghosh Dipayan Sarkar Ram 《Multimedia Tools and Applications》2019,78(18):25753-25779
Multimedia Tools and Applications - Facial Emotion Recognition (FER) is an important research domain which allows us to provide a better interactive environment between humans and computers. Some... 相似文献