随机通胀下基于终止风险的DB养老金计划的保费估值

针对随机通胀以及终止风险对DB养老金计划的养老金支付问题的影响,提出了在随机通胀的条件下养老金福利担保公司(Pension Benefit Guaranty Corporation,PBGC)为基于提前终止和遇险终止风险的DB养老金计划提供担保的保费估值问题;由于DB养老金计划可能发生两类终止而导致养老基金赤字和计划发起人公司破产而未能按照承诺支付养老金,就会产生支付缺口,此时,引入PBGC将缺口的养老金支付给养老金计划受益人.PBGC的引入能够充分保障受益人的利益,大大降低了受益人承担的风险.忽略通货膨胀会使结果有误差,因此,在随机通胀的基础上构建了基于两类终止风险的DB养老金计划的保费估值模型.最后,对模型进行了数值模拟.结果表明,通货膨胀的加入使得保费有所增加,虽然这一结果给计划发起人增加了负担,需要支付更多的保费给PBGC,但却降低了PBGC所承担的风险.该模型引入了随机通胀,使得研究的结果更符合实际.     

基于曲线拟合和SVM的眼动信号分类算法研究

为提高基于EOG的眼动信号分类算法精度,改进基于EOG的人—机交互系统性能,提出了一种基于曲线拟合(curve fitting)与支持向量机(SVM)的眼动信号分类算法(CF-SVM),并设计了新的实验范式,增加了“扫视保持”环节.该算法采用曲线拟合方法进行特征提取,在此基础上,使用SVM分类器对眼动信号进行分类.实验室环境下,对9名眼部活动正常的受试者进行了眼动数据采集与识别,CF-SVM算法的平均分类准确率达到98.3％,与其他几种眼动识别方法相比较,其平均正确率分别提升了9.4％、5.9％、1.0％.实验结果表明,CF-SVM算法在眼动信号识别中表现了良好的性能,具有高的分类精度和鲁棒性.     

矿井物流管理和人员定位系统数据库设计

针对矿井物流管理系统与矿井人员定位系统独立运行导致的成本高、维护困难等问题,提出将2个系统进行相互融合、统一管理的方式,并采用射频识别技术和Microsoft SQL Server 2008数据库软件,设计了一种矿井物流管理和人员定位系统,着重介绍了需求分析及逻辑结构设计阶段的系统数据库设计方案,并给出了主要运输流程数据库表的映射关系。该数据库逻辑结构简单、清晰,具有良好的存储结构、数据共享性和一致性。实际应用表明,该数据库具有较高的实用性和可靠性。     

Minimal explanations of missing values by chasing acquisitional data

Acquisitional issues widely exist in GPS and sensor networks. They pertain to where, when, and how often data is physically acquired (sampled) and delivered to some query processing systems. Due to the dynamic environment that the data is acquired with the change of monitoring time, acquisitional data are typically a time-stamped stream where a time-stamped value could either contain noises or be missing. Aiming to improve the quality of data acquisition, we focus on the explanations of missing values in this paper. Several techniques have been developed to provide the explanation on relational data, however, they cannot be directly applied in acquisitional stream data due to its dynamic feature, such as the “change” of acquisitional stream data between two adjacent monitoring time is often constrained by some rules. We show that an explanation could be incorrect or unreasonable if those constraints are not taken into account. We propose one novel chasing technique by considering both spatial and temporal correlations to explain missing values and guarantee a minimal explanation. Experimental results show that our approach can efficiently return high-quality and minimal explanations of missing values.     

基于FPGA的气溶胶粒径信息存储系统的设计与实现

利用电子学时间多道存储技术,结合大规模可编程逻辑控制器FPGA和高速大容量双端口内存芯片,设计了一种高速大容量气溶胶粒子信息分类计数存储系统,实现了气溶胶粒子的快速识别与分类存储。时间多道系统存储容量高达32 768道,每道计数深度65 536个(16 bit)。     

一个可证明安全的代理签名方案

代理签名是一方将自己签名的能力授权给另一方，是一种很重要的密码协议，目前已知的可证明安全的代理签名还很少。该文利用间隙Diffie-Hellman(GDH)群的特点构造了一个新的代理签名方案，新方案在随机预言模型下是可证明安全的。     

次同步谐振的机—电联合仿真方法

为了克服传统次同步谐振机电耦合仿真中仅采用简化的集中质块轴系模型而不能获取机组轴系细节扭矩动态的缺陷,设计了基于PSCAD和ANSYS软件的机—电联合仿真方法,建立了新的耦合机制,通过数据通信实现了两个软件间转速和转矩等接口信息的交换,从而可用复杂的连续质块模型替代原有的简化质块模型,使机电耦合动态分析更加完整和严谨,进而为深入的疲劳分析提供了基础数据。对印度某电厂机组出现的次同步谐振问题进行了实例分析,获得了轴系特定轴段的动态扭矩响应,验证了方法的可行性和有效性。     

基于XML的构件化软件集成测试方法研究

分析了当前构件化软件集成测试方法的局限性,利用XML技术特性,使用XML描述构件、构件的交互、构件间交互服从的规约、测试用例及测试序列等,并结合基于规约的测试方法,从而提出一种基于XML的规约驱动的构件化软件集成测试方法。     

厌氧—两级SBR—混凝沉淀工艺在城镇小型垃圾填埋场渗滤液处理中的应用

针对垃圾渗滤液性质复杂多变难处理的特点以及城镇小型垃圾填埋场的实际情况,采用厌氧-两级SBR-混凝沉淀组合工艺处理浙江省岱山县生活垃圾填埋场渗滤液.连续40 d的运行结果表明,出水常规指标中除COD外,其余指标可通过优化运行条件基本达到生活垃圾填埋场污染控制标准( GB 16889-2008)要求.该处理工艺流程简单,运行稳定,费用合理,适合城镇小型垃圾填埋场渗滤液处理.     

Real‐time dynamic hoist scheduling for multistage material handling process under uncertainties

Multistage material handling processes are broadly used for manufacturing various products/jobs, where hoists are commonly used to transport inline products according to their processing recipes. When multiple types of jobs with different recipes are simultaneously and continuously handled in a production line, the hoist movement scheduling should be thoroughly investigated to ensure the operational feasibility of every job inline and in the meantime to maximize the productivity if possible. The hoist scheduling will be more complicated, if uncertainties of new coming jobs are considered, that is, the arrival time, type, recipe, and number of new jobs are totally unknown and unpredictable before they join the production line. To process the multiple jobs already inline and the newly added jobs, the hoist movements must be swiftly rescheduled and precisely implemented whenever new job(s) come. Because a reschedule has to be obtained online without violating processing time constraints for each job, the solution identification time for rescheduling must be taken into account by the new schedule itself. All these stringent requisites motivate the development of real‐time dynamic hoist scheduling (RDHS) targeting online generation of reschedules for productivity maximization under uncertainties. Hitherto, no systematic and rigorous methodologies have been reported for this study. In this article, a novel RDHS methodology has been developed, which takes into account uncertainties of new coming jobs and targets real‐time scheduling optimality and applicability. It generally includes a reinitialization algorithm to accomplish the seamless connection between the previous scheduling and rescheduling operations, and a mixed‐integer linear programming model to obtain the optimal hoist reschedule. The RDHS methodology addresses all the major scheduling issues of multistage material handling processes, such as multiple recipes, multiple jobs, multicapacity processing units, diverse processing time requirements, and even optimal processing queue for new coming jobs. The efficacy of the developed methodology is demonstrated through various case studies. © 2012 American Institute of Chemical Engineers AIChE J, 59: 465–482, 2013