Trust and Security in RFID-Based Product Authentication Systems

Product authentication is needed to detect counterfeit products and to prevent them from entering the distribution channels of genuine products. Security is a critical property of product authentication systems. In this paper, we study trust and security in RFID-based product authentication systems. We first present a formal definition for product authentication process and then derive the general chain of trust as well as functional and nonfunctional security requirements for product authentication. Most of the scientific literature that covers the topic focuses on cryptographic tag authentication only. This paper, however, provides a broader view including also other known approaches, most notably location-based authentication. To derive the functional security requirements, we employ the concept of misuse cases that extends the use case paradigm well known in the field of requirements engineering. We argue that the level of security of any RFID-based product authentication application is determined by how it fulfills the derived set of functional and nonfunctional requirements. The security of different RFID-based product authentication approaches is analyzed. To study how RFID supports secure product authentication in practice, we investigate how the current EPC standards conform to the functional security requirements of product authentication and show how the unaddressed requirements could be fulfilled. The benefits of implementing a service that detects the cloned tags in the level of the network's core services are identified.     

基于多尺度特征提取的电力客户欠费风险预测

针对用户拖欠电费频繁发生的现象,如何利用科学方法和技术手段来预测电力客户的欠费风险,降低自身的经营风险,是供电企业急需解决的问题。文中以某地高压用户为例,分析了导致用户欠费的影响因素,从欠费频度、违约时长等多个尺度提取用户欠费风险的特征,并基于逻辑回归算法建立模型用于预测用户欠费风险。模型的评价结果表明,在所获取的用户信息不够全面的情况下,模型的预测准确率、精确率和召回率等评价指标仍较为精准,特别是模型对风险用户的识别较为灵敏。该风险模型可用于指导供电企业制定欠费风险管理对策,提高管理水平。     

Product testing

Most organizations have some type of product test function. The process may be informal and accomplished by the product developers, or more formal with the implementation by an independent testing organization. The article does not cover the location and structure of the testing group. Rather, the function and approach to testing is emphasized: the role of the product tester, the responsibilities placed on the tester and the broad skill sets needed to be successful in this role. Testing is a challenging opportunity for those who wish and/or need to understand the product and its use and user environment, all in a single package. It is a career that is unique from this perspective.     

Processes to Integrate Design With Downstream Applications Through Product Shapes Adaptation

In the aeronautics industry, various stages of a product development process such as physical phenomena (like stress, strain, and thermal ones) or virtual reality simulations are regarded as product views and based on different digital shapes of the same physical component. The shape adaptation processes needed to progress from one stage of the product development process to another one, the multiple shapes needed for a simulation at a given stage of this process are analyzed and shape adaptation operators are presented. Then, it is shown why geometric models adaptation processes from the design stage to downstream applications are important in an industrial design context, and why this is a concurrent engineering enabler. Subsequently, we show how shapes adaptation processes can be achieved through their appropriate formalization and representation using direct acyclic graphs connected to the scene structure of a simulation and the product structure used as input. A process datastructure is also proposed to describe shape adaptation processes and ease their reuse. Finally, based on two EADS case studies, we illustrate how methods and criteria can be set up to produce adapted shapes from computer-aided design data in a controlled and integrated manner.      

谐波治理和管理措施探讨

近年来随着非线性电力负荷的不断增多,谐波给供电企业和用户设备的安全运行和经济效益均带来了较大的影响。因此,对如何创新技术和管理手段以治理谐波作了研究分析和实践,并取得了一定的成效。     

谐波治理和管理措施探讨

近年来随着非线性电力负荷的不断增多,谐波给供电企业和用户设备的安全运行和经济效益均带来了较大的影响。因此,对如何创新技术和管理手段以治理谐波作了研究分析和实践,并取得了一定的成效。     

减碳配额约束下电力客户的模糊聚类分析

在减碳配额约束下．供电公司的客户服务领域将由单纯的供电营销向全面的指导用户优化用电方式和减碳服务方向拓展。考虑电力用户的减碳水平,构建了低碳经济下电力客户价值指标体系,提出运用动态模糊聚类算法细分电力客户的新方法,深入分析了动态聚类时最佳阈值的选取依据,用此方法对某市10名大工业客户进行了实证分析。结果表明,低碳经济下电力客户评价指标体系具备合理性。根据聚类结果,总结了不同类别客户的特点,对供电企业如何展开针对性服务提出了建议。     

统计分析对供电可靠性指标的影响

对我国常用的中压用户统计口径和国外常用的低压用户统计口径的供电可靠性统计分析方法进行分析和比较,指出不同的统计口径会对供电可靠性指标产生差异,推导出此差值的计算公式,以实例验证推导结果的正确性。根据推导结果得出结论并提出建议:低压用户平均停电时间与中压用户平均停电时间之差、低压用户统计口径总用户数与中压用户统计口径总用户数的比值对供电可靠性指标的统计分析结果均有影响;要提高供电可靠性统计分析水平,必须提高基础数据的准确性,建设先进的自动化信息系统,完善管理制度。     

基于半张量积稳定域理论的SVC系统稳定性分析

针对某煤矿10kV配电网络亟需分析SVC装置对系统稳定性影响的实际需要。提出了一种基于半张量积稳定域边界理论的SVC系统稳定分析方法。将半张量积稳定域边界理论应用于装设SVC装置的某煤矿10kV配电网络中,根据实际工况对系统进行稳定裕度指标分析,建立可判断系统稳定性的数学模型,并利用Matlab对系统模型进行仿真,得到SVC装置对系统电压稳定性的影响规律。该方案既简化了计算又可以根据稳定指标判断系统的稳定程度,对系统稳定性的判断有很高的参考价值。     

涵盖县级供电公司的95598系统解决方案及优化

在地市公司95598建设中,如何涵盖县级供电公司服务范围是一个比较复杂的问题,原国电公司的建设规范也没有确定具体的方式,仅提出了3种解决方案。结合西安供电公司的实际情况．提出了充分利用数据网络的远端IP座席方案。方案在缓解中心服务压力的同时,充分发挥了供电服务基层单位的作用,第一时间响应用户的服务请求．从而利用95598系统带动整个西安(及所辖县)的供电客户服务。     

Product liability and the plant engineer: an introduction

The influence of jury verdicts in product liability lawsuits on both manufacturers and suppliers of a wide range of products is growing. Since this influence cannot be ignored, it should be consciously incorporated in as another design input. The major theories of product liability recovery are introduced, along with some suggestions on how to address certain of the concerns raised     

电源系统铅酸蓄电池的监测

备用电源系统用户面临的一个两难问题是依赖电池供应商的对于电池性能的保证呢,还是依赖于独立地监测电池的状态以保证需要时提供可靠的电源支持。这一困惑也使电池供应商与电池用户之间可能产生互不信任的问题。国际上已有愈来愈多的电池用户的决策人倾向应用电池监测设备来保证电源供应。这种趋势对各方都是有利的。电池用户决定对电池进行监测时需要考虑三个问题:监测什么内容?用什么方法监测?如何将所用的经费发挥最大效益?本文介绍电池监测重要性的一些事例;讨论电池监测的内容;测量重要参数的新方法;比较和讨论监测数据和电池状态的关系;提出一些合适的判据以供监测装置的选择与监测结果的分析。     

In situ temperature measurement of a notebook computer - a case study in health and usage monitoring of electronics

Reliability prediction methods do not generally account for the actual life cycle environment of electronic products, which covers their environmental, operating and usage conditions. Considering thermal loads, thermal management strategies still focus on a design for continuous operation that is often determined based on an accumulation of worst-case assumptions. Health monitoring is a method of assessing the reliability of a product in its actual application conditions. A case study in health and usage monitoring of electronic products is presented for a commercial notebook computer. Internal temperatures were dynamically monitored in situ and statistically analyzed during all phases of the life cycle, including usage, storage, and transportation. The effects of power cycles, usage history, CPU computing resources usage, and external thermal environment on peak transient thermal loads were characterized. Such monitored life cycle temperature data could be applied in a life consumption monitoring methodology, to provide damage estimation and remaining life prediction due to specific failure mechanisms influenced by temperature. These findings could contribute to the design of more sustainable, least-energy consumption thermal management solutions.     

产品界面的人性化设计

从产品界面角度分析人性化设计,阐述如何从生理、情感层面给予产品人的个性特征,包括在人机工程、功能角度关注人的使用舒适性,在外形、色彩、材质、产品语意上赋予产品情趣化,从而使产品更宜人、悦人。     

软电线低温下动态弯折试验方法及产品研制

介绍了现有软电线在不同产品标准中的低温弯曲试验方法,结合客户特殊使用要求,编制了软电线的低温弯折性能试验方法,并从导体结构和绝缘材料选用考虑,研制出适应于该低温下动态弯折试验方法的软电线新产品。     

The costs and benefits of real-time pricing: An empirical investigation into consumer bills using hourly energy data and prices

This study analyzed smart meter data to compare how residential consumers would have fared in 2016 under traditional, flat-rate electricity pricing versus the ‘real-time pricing’ program offered by Illinois utility Commonwealth Edison. Although further study is needed with more customers and multiple years, 97% of households in the study would have saved with real-time pricing. The average savings would have been $86.63, or 13.2%, annually. Total savings would have been $29.8 million.     

考虑用户舒适度和经济性的负荷聚合商调度决策分析

负荷聚合商调度决策过程中,忽略底层用户舒适度或依据主观偏好确定舒适度会造成用户不配合,导致调度结果不理想。引入模糊优化解决调度决策中经济性与舒适度之间的冲突,首先基于博弈理论建立权衡用户舒适度和经济成本调度的聚合商决策模型。其次,为了加快博弈模型的求解速度,对博弈模型进行线性化转换并制定了求解算法。最后,通过算例验证了决策模型的有效性,同时对调度结果进行多角度的分析,验证了模糊优化边界条件,分析了舒适度阈值的影响以及储能的替代影响。     

电线电缆导体实测截面积为何不“标称”

在质量抽查中 ,质量监督部门或用户由于不熟悉电线电缆的有关标准 ,会对电缆实测截面积与标称截面积的误差产生质疑。本文通过新旧标准中对导体截面积 (标称 )的规定与导体计算截面积比较及分析 ,认为总是存在着一定的误差。由于电线电缆及其导体标准明确地对导体截面积不作考核 ,而仅对导体的直流电阻值指标作为检测与考核指标 ,因此是允许这种误差的存在。     

适用于不同电力市场行为的电力市场仿真器

设计并开发了一个基于网络结构,能够模拟电力运行方式的电力市场仿真器,并在.NET Frame- work上开发了此电力市场仿真系统。该仿真器采用了ASP.NET 2.0开发用户界面,C#作为编程语言以及采用SOL Server 2000作为后台数据库,这样的结构可以灵活地仿真及图形化显示电力库架构下的日前及实时市场运行行为,计算出市场结清价及结清容量。该电力市场仿真器利用了内嵌于.NET Framework的浏览器/服务器结构的卓越特性,这种结构可以实现基于开放标准和异构平台的分布式网络服务请求。并且,这种基于.NET平台构架的结构很适合用于地理位置相隔甚远的市场参与者(诸如市场运营商、发电商、用户等)进行信息传递。仿真实例显示,该仿真器具有很好的可扩展性和维护性。     

Radio control of air conditioning in Rhode Island

A test is reported in which a VHF-FM radio communication system was used to control the compressors of central air-conditioning systems of 50 residential customers and 35 small commercial customers in Rhode Island between the hours of 12:00 and 5:00 pm during weekdays from June through September of 1988. Topics discussed include recruitment of participants, pre-experiment testing, equipment performance, and analysis of results. The hourly diversified demand reduction attributable to control was 1.0 to 1.6 kW per residence during control hours when the average outside temperature ranges from 88 to 95°F. Commercial units showed a relatively constant demand reduction, on the order of 2.5 kW, at all temperatures in excess of 80°F