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131.
移动代理环境下实现微支付系统—扩展MilliCent协议   总被引:2,自引:0,他引:2  
在整个电子商务活动中,网上支付是其中很重要的一环。对于大额交易来说,关心的主要是安全性。但是,对于交易额不高的交易来说,速度和成本就成了首要考虑的因素。MilliCent协议是一个优秀的微支付协议。但是,它不能够提供一种可使用的“硬通货”,需要首先进行兑换工作,为应用增加了麻烦。这篇文章对Millicent进行了改进,引入了“硬通货”的概念,增强了它的方便性和实用性。  相似文献   
132.
一个基于移动代理的分布式入侵检测系统   总被引:11,自引:0,他引:11  
将新型分布式处理技术--移动代理与入侵检测融为一体,提出了一种基于移动代理的分布式入侵检测系统(DIDS)的模型;实现了基于此模型的分布式入侵检测系统;采取了一些防范措施来保证分布式入侵检测系统自身的安全;模拟入侵实验表明它能够有效地检测来自网络内外的入侵,并具有良好的灵活性、鲁棒性和可扩展性.  相似文献   
133.
传统的用软盘收集信息的方法存在一些不足之处,本文介绍了移动代理技术,给出了用移动代理技术来实现信息收集的方法,对该方法进行了安全性分析,并说明了该方法的优点。  相似文献   
134.
There is an implicit assumption in electronic commerce that induces the buyers to believe that their deals will be handled appropriately. However, after a seller has already committed to a buyer, he may be tempted by several requests though he will not be able to supply them all. We analyze markets in which a finite set of automated buyers interacts repeatedly with a finite set of automated sellers. These sellers can satisfy one buyer at a time, and they can be tempted to break a commitment they already have. We have found the perfect equilibria that exist in markets with a finite horizon, and with an unrestricted horizon. A significant result stemming from our study reveals that sellers are almost always tempted to breach their commitments. However, we also show that if markets' designers implement an external mechanism that restricts the automated buyers actions, then sellers will keep their commitments.  相似文献   
135.
氯化物排放与燃烧脱氯技术工业性试验研究   总被引:1,自引:0,他引:1  
蒋旭光  李香排  李琦  池涌  严建华 《热力发电》2004,33(3):37-39,49
对某电厂煤粉炉除尘器前后HC1排放量进行了实测,并在垃圾流化床锅炉和链条炉上进行了燃烧脱氯试验。研究结果表明:(1)含氯废弃物是垃圾焚烧炉HC1排放最主要来源;(2)在流化床中,煤中氯化物排放浓度和排放率较低,单一钙基吸收剂的固氯效果比在链条炉中明显,脱氯剂种类与脱氯剂添加量对脱氯效果有一定影响;(3)链条炉燃烧温度高、燃料停留时间长,燃烧脱氯应采用耐高温脱氯剂,以解决脱氯产物CaCl2的再分解问题;(4)对于链条炉,采用脱氯剂半预混半喷射两段燃烧脱氯方式可使脱氯产物在炉内停留时间大大缩短,有效降低脱氯产物的分解率,因此可获得较好的脱氯效果。  相似文献   
136.
Biofiltration, a process in which contaminated air is passed through a biologically active bed, can be used to remove volatile organic pollutants from air streams. While most biofilters rely on bacteria to degrade organic pollutants, biofilters utilizing a fungal biofilm have the potential to be an efficient and robust treatment alternative. In this study, two surfactants were evaluated for their ability to activate the spores of the fungus Exophiala lecanii-corni and reduce the start-up period typically observed in fungal vapor-phase bioreactors. Sodium dodecyl sulfate, an anionic surfactant, was found to inhibit growth of E. lecanii-corni. Polyoxyethylene sorbitan monolaurate (Tween 20), a nonionic surfactant, stimulated bud formation and enhanced toluene degradation in E. lecanii-corni cultures. Tween 20 was also found to enhance inoculum development by shortening the lag period during culture growth. However, when bioreactors were presoaked in medium containing Tween 20, washout of the fungal cells occurred during inoculation, inhibiting the initial fungal biofilm development. After a seven-day start-up period, no detrimental effects on reactor performance due to residual Tween 20 were observed, and toluene elimination capacities of up to 150?g/m3?h were achieved.  相似文献   
137.
Software engineers of multi‐agent systems (MASs) are faced with different concerns such as autonomy, adaptation, interaction, collaboration, learning, and mobility, which are essentially different from classical concerns addressed in object‐oriented software engineering. MAS developers, however, have relied mostly on object‐oriented design techniques and programming languages, such as Java. This often leads to a poor separation of MAS concerns and in turn to the production of MASs that are difficult to maintain and reuse. This paper discusses software engineering approaches for MASs, and presents a new method for integrating agents into object‐oriented software engineering from an early stage of design. The proposed approach encourages the separate handling of MAS concerns, and provides a disciplined scheme for their composition. Our proposal explores the benefits of aspect‐oriented software development for the incorporation of agents into object‐oriented systems. We also illustrate our aspect‐oriented approach through the Portalware multi‐agent system, a Web‐based environment for the development of e‐commerce portals. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
138.
The purpose of this study is to investigate the effect of treated natural zeolite on the flow behavior, morphology, thermal, and mechanical properties in recycled polyolefin blends. A model polymer blend consisting of 95 wt% polyolefines and 5 wt% polystyrene was studied. Compositions from this recycled blend and dehydrated zeolite in a narrow concentration range (0–5 wt%) were treated with maleic anhydride-grafted polypropylene and initiator dicumyl peroxide. The compositions were characterized by capillary rheometry, wide-angle X-ray scattering, differential scanning calorimetry, scanning electron microscopy, and mechanical tests. The results show a compatibilizing effect of treated zeolite expressed by increase of shear viscosity and improvement of interfacial interactions and impact strength. The results can open wide possibilities for utilization of treated zeolite in recycling of unsorted polymer wastes.  相似文献   
139.
介绍生物制剂处理工艺、主要设备、技术参数及生产运行情况.1年多应用实践表明,该工艺在污酸废水处理中发挥重要作用.通过生物制剂处理工艺处理后的废水,满足硫酸车间循环水应用条件和烧结车间系统补水条件,从而使得烧结车间的水循环系统达到平衡.  相似文献   
140.
Zinc oxide (ZnO) nanoparticles have been proven to have strong antibacterial activity against food borne pathogens. The practical applications of different concentrations (0, 1, 3, 5 and 8 mM) of ZnO suspensions containing 0.3% citric acid were investigated against the pathogenic bacteria like, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Bacillus cereus. Zinc oxide suspensions (0, 1, 3, 5 and 8 mM) containing citric acid have shown a significant inhibitory effect on the growth of all strains during 12 h of incubation. Our results have also shown that 5 and 8 mM suspensions of ZnO were the most effective on all strains. These data suggested that the antibacterial activity of ZnO was concentration dependent. Thus 5 mM and 8 mM ZnO were selected for further studies, carried out in mango juice, as they showed a significant growth inhibition in TSB. ZnO NPs were more capable of reducing initial growth counts of all the above stated strains in mango juice. Results have also exhibited that ZnO and citric acid had inhibitory effect on the growth of all strains during 24 h culture period in mango juice, as compared to the control experiment, which was further confirmed in liquid culture. This is the first report, describing the antibacterial activity of ZnO NPs in mango juices that showed the potential of these nanoparticles for use as an antibacterial agent in the food industry.  相似文献   
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