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排序方式: 共有1079条查询结果,搜索用时 15 毫秒
1.
Wireless Personal Communications - In the present scenario, there is a boom in the demand of the users to achieve increased capacity, high data, low latency, and high-performance rates. 5G New... 相似文献
2.
A study of the energy consumption characteristics of cryptographic algorithms and security protocols 总被引:2,自引:0,他引:2
Potlapally N.R. Ravi S. Raghunathan A. Jha N.K. 《Mobile Computing, IEEE Transactions on》2006,5(2):128-143
Security is becoming an everyday concern for a wide range of electronic systems that manipulate, communicate, and store sensitive data. An important and emerging category of such electronic systems are battery-powered mobile appliances, such as personal digital assistants (PDAs) and cell phones, which are severely constrained in the resources they possess, namely, processor, battery, and memory. This work focuses on one important constraint of such devices-battery life-and examines how it is impacted by the use of various security mechanisms. In this paper, we first present a comprehensive analysis of the energy requirements of a wide range of cryptographic algorithms that form the building blocks of security mechanisms such as security protocols. We then study the energy consumption requirements of the most popular transport-layer security protocol: Secure Sockets Layer (SSL). We investigate the impact of various parameters at the protocol level (such as cipher suites, authentication mechanisms, and transaction sizes, etc.) and the cryptographic algorithm level (cipher modes, strength) on the overall energy consumption for secure data transactions. To our knowledge, this is the first comprehensive analysis of the energy requirements of SSL. For our studies, we have developed a measurement-based experimental testbed that consists of an iPAQ PDA connected to a wireless local area network (LAN) and running Linux, a PC-based data acquisition system for real-time current measurement, the OpenSSL implementation of the SSL protocol, and parameterizable SSL client and server test programs. Based on our results, we also discuss various opportunities for realizing energy-efficient implementations of security protocols. We believe such investigations to be an important first step toward addressing the challenges of energy-efficient security for battery-constrained systems. 相似文献
3.
Considers the applicability of algorithm based fault tolerance (ABET) to massively parallel scientific computation. Existing ABET schemes can provide effective fault tolerance at a low cost For computation on matrices of moderate size; however, the methods do not scale well to floating-point operations on large systems. This short note proposes the use of a partitioned linear encoding scheme to provide scalability. Matrix algorithms employing this scheme are presented and compared to current ABET schemes. It is shown that the partitioned scheme provides scalable linear codes with improved numerical properties with only a small increase in hardware and time overhead 相似文献
4.
Vascular injuries may occur as complications of elbow dislocation and usually involve the brachial artery. A case report is presented in which only the radial artery was compromised as a result of the dislocation. 相似文献
5.
Animesh Chakravorty 《Israel journal of chemistry》1985,25(2):99-105
Model complexes of nickel(III) and nickel(IV) are furnished by hexadentate and tridentate oxime-imine-amine ligands derived by the condensation of biacetyl monoxime with amines. The synthesis, characterisation, structure, redox equilibria and reactivity of these complexes are critically reviewed. Correlations and generalisations pertaining to oxidation state stability, electroprotic equilibria and reaction mechanisms are examined. The possible significance of the present complexes in the context of the nickel-containing methanogenic enzymes is noted. 相似文献
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DESP: a distributed economics-based subcontracting protocol for computation distribution in power-aware mobile ad hoc networks 总被引:1,自引:0,他引:1
In this paper, we present a new economics-based power-aware protocol, called the distributed economic subcontracting protocol (DESP) that dynamically distributes task computation among mobile devices in an ad hoc wireless network. Mobile computation devices may be energy buyers, contractors, or subcontractors. Tasks are transferred between devices via distributed bargaining and transactions. When additional energy is required, buyers and contractors negotiate energy prices within their local markets. Contractors and subcontractors spend communication and computation energy to relay or execute buyers' tasks. Buyers pay the negotiated price for this energy. Decision-making algorithms are proposed for buyers, contractors, and subcontractors, each of which has a different optimization goal. We have built a wireless network simulator, called ESIM, to assist in the design and analysis of these algorithms. When the average communication energy required transferring a task is less than the average energy required to execute a task, our experimental results indicate that markets based on our protocol and decision-making algorithms fairly and effectively allocate energy resources among different tasks in both cooperative and competitive scenarios. 相似文献
9.
Animesh Chakrabarti Man Mohan Sharma 《Journal of the American Oil Chemists' Society》1992,69(12):1251-1253
Anhydrous esterification of myristic acid with propylene was carried out in the temperature range of 110–145°C and pressure
from 190–195 psig in the presence of Amberlyst-15 (cation exchange resin) and Filtrol-24 (acid-treated clay) as catalysts.
The product ester, isopropyl myristate finds use in cosmetic and topical medicinal preparations where good absorption through
the skin is desired. Filtrol-24 is the catalyst of choice, and the recommended operating temperature is 130°C with a pressure
of 190 psig. 相似文献
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