存在工作历程产品的加速寿命试验统计分析

加速寿命试验(ALT)可在较短时间内获得产品的寿命及可靠性信息.利用ALT对产品的剩余寿命进行评估时,常常将已工作过的产品进行抽样并投入试验,在这一类样本的ALT数据统计分析时如何处理初始工作时间,成为ALT应用中的一个重要问题.工程实际中评估此类样本的剩余寿命时常常忽略初始工作时间,将其视为"用后如新"或"无记忆性"产品.但此假设必须以产品寿命服从指数分布为前提,而大部分机电产品的寿命服从Weibull分布,因而该方法在应用时必然会产生较大误差.针对这一问题提出了一种新的基于时间折算的ALT数据统计分析方法,并利用Monte Carlo仿真对其估计特性进行对比研究,结果表明此方法能有效评估存在初始工作历程产品的剩余寿命,估计精度优于原方法.     

稳像式火控系统实车训练装置的研制

该训练装置可以在安装稳像式火控系统的坦克上完成射击基础练习的训练与考核.它以单片机为核心,在射击操作与实车相同的条件下,具有自动检靶,自动记录发射数、命中数,自动变换目标,自动报警,自动评定和显示成绩等功能.射手可独自在坦克内操作,自行开始练习,自我检查操作结果.     

松耦合设计在计算机脆弱性测评系统中的应用

运用松耦合设计思想,对计算机脆弱性测评系统中两个子系统的组成和实现进行了研究。提出多准则测评子系统的Web数据库实现和CVE测评子系统的多层MAS实现方法,并对其实现算法和技术要点进行了论述。     

漏磁信号特征提取及检测研究

介绍了漏磁检测原理和用有限元法计算漏磁场的方法,漏磁场法向分量的峰-峰值随缺陷深度增加而增加,峰-峰值间隔随缺陷宽度增大而增大。在检测中,先去除漏磁信号的奇异值,然后用峰-峰值算法提取缺陷信号特征,根据信号的峰-峰值大小和信号梯度变化作为缺陷判别标准。     

一种面向故障的软件测试新方法

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.     

数据驱动自动化测试方法研究

介绍了一种数据驱动方法,用以实现自动化测试.通过对测试数据的产生及选取、控制数据调度的研究发现,不仅应用更灵活的数据驱动方法,对程序进行更深、更广的测试,而且无需编写脚本,只需填写测试表,即可完成全面的自动化测试.这样,即使非技术人员也能够开发测试数据,完成数据驱动自动化测试.     

星空点源背景红外辐射场景生成模型

星空场景建模是空间目标识别与跟踪的关键技术之一.基于中段空间实验红外天文星表(MSX-IRAC),通过位置计算得到该星表内恒星在指定观测时刻、观测地点投影到视场所在平面的坐标,同时利用改进的光谱模板技术,生成视场内所有点源星体的红外光谱(1.2～35 μm),并对光谱积分得到指定谱段的辐射量,最后将恒星位置和辐射信息在二维图像上表现出来,从而实现了一个星空点源背景红外辐射场景生成模型,并通过实例仿真验证了该模型的正确性.     

采用弹道修正技术的红外干扰弹性能优化

针对弹道修正弹的高维非线性特性导致的性能优化难题,改变概念设计阶段传统的串行设计方式,提出了一种基于实验设计(Design Of Experiments,DOE)和响应面(Response Surface Methodology,RSM)的智能优化算法,定义基本的弹丸结构模型以及相关的设计参数.在DOE的基础上,将设计...     

Equity in genetic newborn screening

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.     

Fuzzy recognition of missile borne multi-line array infrared detection based on size calculating

In order to improve the infrared detection and discrimination ability of the smart munition to the dy-namic armor target under the complex background, the multi-line array infrared detection system is established based on the combination of the single unit infrared detector. The surface dimension features of ground armored targets are identified by size calculating solution algorithm. The signal response value and the value of size calculating are identified by the method of fuzzy recognition to make the fuzzy classification judgment for armored target. According to the characteristics of the target signal, a custom threshold de-noising function is proposed to solve the problem of signal preprocessing. The multi-line array infrared detection can complete the scanning detection in a large area in a short time with the characteristics of smart munition in the steady-state scanning stage. The method solves the disadvan-tages of wide scanning interval and low detection probability of single unit infrared detection. By reducing the scanning interval, the number of random rendezvous in the infrared feature area of the upper surface is increased, the accuracy of the size calculating is guaranteed. The experiments results show that in the fuzzy recognition method, the size calculating is introduced as the feature operator, which can improve the recognition ability of the ground armor target with different shape size.