基于LoadRunner自动化应用程序接口的舰船装备软件测试系统设计与实现

针对舰船装备软件接口交互信息量大,利用现有动态测试技术对此类软件开展测试工作时效率较低,自动化测试水平亟待提高的现状,归纳分析了舰船装备软件测试系统的主要能力需求,研究了接口协议形式化、测试用例自动生成、测试用例自动驱动、通信接口转换等关键技术,并以上述技术为基础给出了舰船装备软件测试系统的体系架构设计方案,进而实现了一种基于LoadRunner自动化应用程序接口(LoadRunner Automation API)的舰船装备软件测试系统,为舰船装备软件提供了一种可行的自动化测试手段;该测试系统主要包括测试管理模块、测试用例生成模块、测试用例驱动模块和数据收集与分析模块;采用该测试系统能够有效提高舰船装备软件的测试效率。     

基于STM32的温湿度变送器设计

针对目前常见的电流型温湿度变送器恒流输出特性较差、精度较低、校准繁琐的不足,给出了一种基于STM32单片机的温湿度变送器设计方案。该电路以STM32单片机为控制核心,以SHT11数字式温湿度传感器采集环境温湿度。通过STM32的内部12位D/A输出模块将温湿度转换为模拟电压信号。随后,该电压信号通过V/I转换电路变为4～20mA的模拟电流信号。研究了常见V/I转换电路的原理并提出改进电路方案。最后,基于STM32的内部FLASH存储功能给出了一种上位机软件校准方案。通过对比仿真和实验表明,该变送器具有成本较低、恒流特性较好、精度较高、校准快捷方便的优点,能够满足工农业生产中常规温湿度测量的要求。     

Imperfect debugging in software reliability: A Bayesian approach

The objective of studying software reliability is to assist software engineers in understanding more of the probabilistic nature of software failures during the debugging stages and to construct reliability models. In this paper, we consider modeling of a multiplicative failure rate whose components are evolving stochastically over testing stages and discuss its Bayesian estimation. In doing so, we focus on the modeling of parameters such as the fault detection rate per fault and the number of faults. We discuss how the proposed model can account for “imperfect debugging” under certain conditions. We use actual inter-failure data to carry out inference on model parameters via Markov chain Monte Carlo methods and present additional insights from Bayesian analysis.     

Short-term and long-term competition between providers of shrink-wrap software and software as a service

Software as a service (SaaS) has moved quickly from a peripheral idea to a mainstream phenomenon. By bundling a software product with delivery and maintenance service, SaaS providers can effectively differentiate their products with traditional shrink-wrap software (SWS). This research uses a game theoretical approach to examine short- and long-term competition between SaaS and SWS providers. We analyze the factors that affect equilibrium outcomes, including user implementation costs, SaaS provider’s operation efficiency, and quality improvement over time. Bundling software with service lowers software implementation cost for users, and our results suggest that it increases equilibrium prices. In providing software services, SaaS providers have to incur significant operation cost. In the long run, service operation cost may significantly affect SaaS firm’s ability to improve its software quality.     

Extensible Software Systems in Oberon

Abstract

Extensible software systems play an important role in prototyping environments where a fast compile-and-test turnaround is required. Typically, extensible software systems combine ways to reuse code, an approach to object-oriented programming, and ways to preserve state from one session to another. In this article we introduce the Oberon system from the perspective of an extensible system. In Oberon, the stated requirements manifest themselves as separate hierarchies related to modularity, the type system, runtime system organization, and persistency. We discuss issues related to these hierarchies and the approaches selected in Oberon for their implementation. The article is mainly a short introduction to Oberon and a summary of what has been accomplished with this system.     

An empirical study of ICASE learning curves and probability bounds for software development effort

In this paper, we investigate the existence of learning curves in software development. Under the assumption of independent and identical distribution (iid) of programmer’s experience and identical effort-experience learning curve relationship for different programmers, we illustrate the existence of an exponentially decreasing learning curve relationship between a programmer’s effort and his/her ICASE tool experience, and show that the effort-experience relationship is inelastic when a programmer’s ICASE tool experience is low. We analyze the impact of our assumptions on actual software development effort, and propose a tight probability upper bound and a central-limit theorem based probability estimator for estimating the approximate probability that the software development effort will be less than or equal to a certain number. Examples to illustrate the use of the probability estimator are also provided.     

记数抽样检查方案设计与分析软件研制

利用VisualC++6.0Windows开发设计了抽样方案分析与设计软件。软件集成多种功能于一窗口,直观性强,操作方便,计算速度快,不仅可对现行抽样方案检索与分析,而且还可对一次、二次、五次和序贯抽样方案进行设计与分析,并作计算机模拟,可供抽样检查和抽样方案设计人员使用。     

Four Kinds of Microwave Measurements to Make Use of an Automatic Slotted-Line System

An automatic slotted line system controlled with the micro-computer IBM 80486 which we have developed had been reported. In this paper, the measuring principles and the software designs of impedance, attenuation, phase shift and detection law of diode measurement to make use of this system will be described, some typical measurement results will be given. This method is adaptable for MM-Wave band and other Micro-wave band.