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1.
We present a group testing model for items characterized by marker random variables. An item is defined to be good (defective) if its marker is below (above) a given threshold. The items can be tested in groups; the goal is to obtain a prespecified number of good items by testing them in optimally sized groups. Besides this group size, the controller has to select a threshold value for the group marker sums, and the target number of groups which by the tests are classified to consist only of good items. These decision variables have to be chosen so as to minimize a cost function, which is a linear combination of the expected number of group tests and an expected penalty for missing the desired number of good items, subject to constraints on the probabilities of misclassifications. We treat two models of this kind: the first one is based on an infinite population size, whereas the second one deals with the case of a finite number of available items. All performance measures are derived in closed form; approximations are also given. Furthermore, we prove monotonicity properties of the components of the objective function and of the constraints. In several examples, we study (i) the dependence of the cost function on the decision variables and (ii) the dependence of the optimal values of the decision variables (group size, group marker threshold, and stopping rule for groups classified as clean) and of the target functionals (optimal expected number of tests, optimal expected penalty, and minimal expected cost) on the system parameters.© 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   

2.
边界附近的点对程序故障更加敏感.针对这一特征,提出了一种基于程序域边界分析的测试方法.从被测程序本身出发,进行定义域确定及子域划分,分析定义域边界和子域边界,并跟据其边界测试点产生测试用例,以检测域边界附近的处理.实验表明对定义域边界及其子域边界进行测试,可有效地提高故障覆盖率.  相似文献   

3.
随着Web应用软件的迅猛发展,作为保证Web质量和可靠性的重要手段,Web应用软件的测试越来越受到人们的重视.通过对当今最常用的Web测试方法、思想以及工具的研究.分析对比了常用的模型,从而提出了一种基于智能控制理论的Web应用软件测试模型.  相似文献   

4.
One of the important features of any software system is its operational profile. This is simply the set of all operations that a software is designed to perform and the occurence probabilities of these operations. We present a new model on optimal software testing such that testing is done sequentially using a set of test cases. There may be failures due to the operations in each of these cases. The model parameters, consisting of testing costs and failure rates, all depend on the cases used and the operations performed. Our aim is to find the optimal testing durations in all of the cases in order to minimize the total expected cost. This problem leads to interesting decision models involving nonlinear programming formulations that possess explicit analytical solutions under reasonable assumptions. © 2000 John Wiley & Sons, Inc., Naval Research Logistics 47: 620–634, 2000  相似文献   

5.
State‐level newborn screening allows for early treatment of genetic disorders, which can substantially improve health outcomes for newborns. As the cost of genetic testing decreases, it is becoming an essential part of newborn screening. A genetic disorder can be caused by many mutation variants; therefore, an important decision is to determine which variants to search for (ie, the panel design), under a testing budget. The frequency of variants that cause a disorder and the incidence of the disorder vary by racial/ethnic group. Consequently, it is important to consider equity issues in panel design, so as to reduce disparities among different groups. We study the panel design problem using cystic fibrosis (CF) as a model disorder, considering the trade‐offs between equity and accuracy, under a limited budget. Most states use a genetic test in their CF screening protocol, but panel designs vary, and, due to cost, no state's panel includes all CF‐causing variants. We develop models that design equitable genetic testing panels, and compare them with panels that maximize sensitivity in the general population. Our case study, based on realistic CF data, highlights the value of equitable panels and provides important insight for newborn screening practices.  相似文献   

6.
在阐述了电子对抗装备软件特点的基础上,对研制电子对抗装备软件过程中的测试策略与方法进行了初步的研究,并对在实施测试过程中的几个问题进行了探讨.  相似文献   

7.
We introduce and study a generalization of the classic sequential testing problem, asking to identify the correct state of a given series system that consists of independent stochastic components. In this setting, costly tests are required to examine the state of individual components, which are sequentially tested until the correct system state can be uniquely identified. The goal is to propose a policy that minimizes the expected testing cost, given a‐priori probabilistic information on the stochastic nature of each individual component. Unlike the classic setting, where variables are tested one after the other, we allow multiple tests to be conducted simultaneously, at the expense of incurring an additional set‐up cost. The main contribution of this article consists in showing that the batch testing problem can be approximated in polynomial time within factor , for any fixed . In addition, we explain how, in spite of its highly nonlinear objective function, the batch testing problem can be formulated as an approximate integer program of polynomial size, while blowing up its expected cost by a factor of at most . Finally, we conduct extensive computational experiments, to demonstrate the practical effectiveness of these algorithms as well as to evaluate their limitations. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 275–286, 2016  相似文献   

8.
This paper introduces an efficient heuristic procedure for a special class of mixed integer programming problems called the uncapacitated warehouse (plant) location problem. This procedure is derived from the branching decision rules proposed for the branch and bound algorithm by the author in an earlier paper. It can be viewed as tracing a single path of the branch and bound tree (from the initial node to the terminal node), the path being determined by the particular branching decision rule used. Unlike branch and bound the computational efficiency of this procedure is substantially less than linearly related to the number of potential warehouse locations (integer variables) in the problem. Its computational efficiency is tested on problems found in the literature.  相似文献   

9.
战场复杂电磁环境对防空导弹提出了抗拖曳式干扰的新要求,在组织进行实际对抗效果飞行检验时,存在导弹威胁拖曳式诱饵载机安全的风险,影响试验的组织和决策。介绍了拖曳式干扰的系统组成、工作原理和实际使用问题,提出了基于现有硬体拖靶系统构建拖曳式干扰系统的方法,分析了拖曳式诱饵对拖靶系统飞行性能的影响。该构建方法可以有效解决困扰试验的安全问题,为后续系统的建设和试验提供参考。  相似文献   

10.
李兵 《国防科技》2020,41(3):19-24,66
突发重大疫情后,科学的风险管理方法可为有效规避和控制风险提供有力支撑。在突发重大疫情风险管理中,风险识别是基础,风险评估是核心,风险控制是目的。本文系统梳理与分析了风险管理中的常用方法,包括风险识别中的现场勘查法、事故树分析法、过程回溯法、专家认证法和案例分析法等5种方法,风险评估中的风险坐标图法、关键风险指标法、蒙特卡罗法、因果关系法和综合评价法等5种方法,以及风险控制决策中的成本收益决策法、决策树法和损失期望值决策法等3种方法,并对每种方法如何在此次由新型冠状病毒引发的突发重大疫情中实践应用进行了举例说明,可为今后在应对突发重大疫情时进行科学风险识别、有效风险评估和精准风险控制决策提供借鉴与参考。  相似文献   

11.
综合考虑了嵌入式软件的特点,将遗传算法应用于搜索全面覆盖软件特殊路径的测试用例生成的问题,合理构建了嵌入式软件测试用例自动生成系统,给出了系统流程图,改进了部分算子,使搜索效果得以加强,并分析了交叉率、变异率等参数的取值范围,通过改变不同的参数值得到对比图,以确定适合该系统的最佳参数值,并针对实际汇编语言编写的嵌入式软件指定路径进行仿真测试,从理论和实践上证明了该思路的正确性和可行性。  相似文献   

12.
某型装甲车载反坦克导弹系统的发射制导装置,集光、机、电多种技术于一体,技术状态易受装载、运输等因素的影响。在导弹射击前,一般应在现场对发射制导装置进行快速检测以确定其技术状态。为了解决现场快速检测问题,分析了该型导弹系统发射制导装置的结构和技术特点,确定了现场快速检测的内容:用点光源的电视图像检测两个光轴不平度;用电压比较法检测点火电压和点火程序正确性;用指令频率变化检测控制指令正确性。开发了适于现场快速检测的装置,为部队射击保障提供了一种决策支持方法。  相似文献   

13.
We consider a software reliability model where the failure rate of each fault depends on the specific operation performed. The software is tested in a given sequence of test cases for fixed durations of time to collect data on failure times. We present a Bayesian analysis of software failure data by treating the initial number of faults as a random variable. Our analysis relies on the Markov Chain Monte Carlo methods and is used for developing optimal testing strategies in an adaptive manner. Two different models involving individual and common faults are analyzed. We illustrate an implementation of our approach by using some simulated failure data. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48:747–763, 2001  相似文献   

14.
像增强器三维噪声测试技术   总被引:6,自引:0,他引:6  
以微光像增强器为实验研究对象,分析了微光像增强器的噪声来源,提出了微光像增强器噪声特性的三维测试分析技术,建立了同时考虑时间域和空间域噪声的微光像增强器噪声测试理论模型,并用三维曲线描绘出空间域和时间域噪声的分布情况。  相似文献   

15.
魏龙  刘乐  刘吉吉  马群 《国防科技》2021,42(4):69-75
传统固体火箭发动机无损检测图像判读工作存在人工识别效率低、图像数据分散及数据利用率低等问题。本文借助机器学习算法与计算机视觉技术,利用大量发动机无损检测图像数据开展无损检测图像数据预处理、边缘检测以及数据模型训练和应用等技术研究,探索快速、准确获得发动机无损检测图像数据特征的方法,深入挖掘固体发动机无损检测数据的内在联系,找到潜在规律。本研究不仅为固体发动机无损检测图像判读提供了一种准确、高效的手段,同时,能够为发动机无损检测图像识别、测量、判读和发动机相关故障模式分析与故障诊断提供数据和决策支持,也能够为未来机器学习在固体发动机无损检测图像判读领域的深入应用提供实践探索和理论研究方面的参考。  相似文献   

16.
面向对象的软件开发给测试带来了新的挑战,传统的测试技术不能直接用于面向对象的软件测试中,必须对其进行扩充和完善.类级测试是面向对象测试过程中的一个重要阶段,而类状态的测试是类级测试的核心.作者将扩充后的黑盒测试技术应用到类状态的测试过程中,可直接使用方法级的测试数据有效测试类中方法间的交互及其类状态的变化.最后,通过一个实例说明对类级状态的测试及其测试用例的生成.  相似文献   

17.
A new piece of equipment has been purchased in a lot of size m. Some of the items can be used in destructive testing before the item is put into use. Testing uncovers faults which can be removed from the remaining pieces of equipment in the lot. If t < m pieces of equipment are tested, then those that remain, m1 = mt, have reduced fault incidence and are more reliable than initially, but m1 may be too small to be useful, or than is desirable. In this paper models are studied to address this question: given the lot size m, how to optimize by choice of t the effectiveness of the pieces of equipment remaining after the test. The models used are simplistic and illustrative; they can be straightforwardly improved. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 623–637, 1997  相似文献   

18.
Accelerated life testing (ALT), enhanced by optimal test plans, has been widely accepted in practice as a quick approach for estimating the reliability of a product. From the estimation result, preventive maintenance schedules can be determined to ensure the performance of the product under its normal operating conditions. By default, maintenance decision‐making is regarded as the last and least rewarding step. However, sometimes the maintenance schedules, such as preventive maintenance intervals, are predetermined due to customer concerns and/or by various mandatory regulations and rules. Under such circumstances, how to accurately estimate the expenditure (e.g., on maintenance or spare parts management) associated with these maintenance requirements becomes an important issue. A viable solution is to incorporate the maintenance requirements into ALT plans. This paper provides an approach for the optimal design of ALT plans oriented by a mandatory periodical replacement schedule subject to a discounted penalty. The objective is to improve the estimation accuracy of the economic impact of this maintenance requirement. A numerical experiment is provided to demonstrate the approach in practical use. © 2008 Wiley Periodicals, Inc. Naval Research Logistics 2009  相似文献   

19.
末制导雷达干扰决策的模糊评估方法研究   总被引:1,自引:0,他引:1  
为了适应水面舰艇反导作战的需要 ,提出了一种评估末制导雷达干扰决策的方法。建立了导弹末制导雷达干扰决策评估模型 ,在此基础上 ,运用模糊综合评估的方法 ,对导弹末制导雷达干扰决策进行了综合评估。以干扰某型反舰导弹为例 ,对评估方法进行了试验验证。结果表明 ,该评估方法对评估末制导雷达干扰决策十分有效  相似文献   

20.
一种面向故障的软件测试新方法   总被引:14,自引:0,他引:14  
面向故障的软件测试方法是今后软件测试技术研究的主要内容.和传统的面向整个软件的测试方法相比,面向故障的测试方法对故障的检测针对性更强,特别是对传统测试方法难以检测的故障如存储器泄露故障、数组越界故障、空指针引用故障等的检测是非常有效的.从方法学上讲,面向故障的测试方法标志着一个测试理论的成熟,在测试方法学中具有里程碑的意义.面向故障测试方法有2个问题需要解决:①软件的故障模型,②面向该模型的自动测试方法,此文重点论述软件的故障模型问题.  相似文献   

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