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一种电子系统测试性模型的研究 总被引:1,自引:0,他引:1
测试性是系统和设备的一种便于测试和诊断的重要设计特性,对现代的航空电子设备、武器装备等复杂系统的维护性、可靠性和可用性有很大影响。在对测试性建模理论进行研究的基础上,借鉴多信号流图模型和eXpress信息模型,提出了一种适合电子系统的测试性模型——ESTIM(electrotic system testability information model)模型,该模型在表示方法上与EDA软件相兼容,可结合功能相关性和故障模式相关性方便地对电子系统进行测试性分析。 相似文献
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Designers usually begin with a database to look for historical design solution, available experience and techniques through design documents, when initiating a new design. This database is a collection of labeled design documents under a few of predefined categories. However, little work has been done on labeling a relatively small number of design documents for information organization, so that most of design documents in this database can be automatically categorized.This paper initiates a study on this topic and proposes a methodology in four steps: design document collection, documents labeling, finalization of documents labeling and categorization of design database. Our discussion in this paper focuses on the first three steps. The key of this method is to collect relatively small number of design documents for manual labeling operation, and unify the effective labeling results as the final labels in terms of labeling agreement analysis and text classification experiment. Then these labeled documents are utilized as training samples to construct classifiers, which can automatically give appropriate labels to each design document.With this method, design documents are labeled in terms of the consensus of operators’ understanding, and design information can be organized in a comprehensive and universally accessible way. A case study of labeling robotic design documents is used to demonstrate the proposed methodology. Experimental results show that this method can significantly benefit efficient design information search. 相似文献
256.
Takeshi Emura 《Computational statistics & data analysis》2010,54(12):3033-3043
A goodness-of-fit testing procedure for Archimedean copula (AC) models is developed based on right-censored data. The proposed approach extends an existing method, which is suitable for the Clayton model, to general AC models. Asymptotic properties of the proposed test statistics under the true model assumption are derived. Simulation analysis shows that the proposed test has reasonable performance. Finally, two real data examples are analyzed for illustrative purposes. 相似文献
257.
We revisit the problem of determining confidence interval widths for the comparison of means. For the independent two-sample (two-sided) case, Goldstein and Healy (1995) draw attention to the fact that comparisons based on 95% error bars are not very effective in assessing the statistical significance of the difference in means and derive the correct confidence interval for such a comparison. We provide an extension to Goldstein and Healy (1995) to account for the correlation structure and unequal variances. We use the results to develop rules of thumb for evaluating differences, in an exploratory manner, like Moses (1987) and Cumming (2009), from the independent case. We illustrate the method for the simple comparison of two means in a real data set, provide R code that may be easily implemented in practice, and discuss the extension of the method to other applied problems. 相似文献
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Drawing upon the Entertainment–Education paradigm, this study evaluated the effectiveness of a computer-aided interactive test designed for stress management education targeting college students. The presence (vs. absence) of a virtual agent incorporated into the interactive test was proposed as the key factor that induces enjoyment and educational outcomes. The interactive test consisted of scenarios describing stressful situations that could occur in college students’ everyday lives. Furthermore, college students could relate the concerns raised by these hypothetical situations to the ways they manage their stress and mental health. After the student’s choice behavior in each scenario, a virtual agent conveyed health-related educational messages via a text-modal dialogue box. Participants who took the interactive test in which there was a virtual agent perceived the test as more educational and entertaining than those who took the test without a virtual agent. Results of a path analysis also revealed a significant mediating role of enjoyment on educational outcomes (i.e., students’ enjoyment of the interactive test mediated the effects of the presence of a virtual agent on their perceived educational value of health information), thus confirming the Entertainment–Education link. In addition, engaging in the interactive test resulted in stress management self-efficacy improvement. Theoretical and practical implications are discussed. 相似文献
259.
该文设计了立式转鼓式轮胎耐久性测试台,由西门子直流调速系统实现轮胎的速度闭环控制,液压加载系统实现载荷闭环控制,结合PLC与工控机实现对试验机所要求的各种控制功能外,还能够通过人机界面实现试验程序的输入和编辑功能,以及试验数据的存储与打印。 相似文献
260.
为了检测航空相机工作是否正常,并可对有故障相机进行故障诊断,该文设计了一套自动测试软件系统。该系统能模拟飞机的任务管理系统与相机以ARINC429总线传输方式传输数据,并按相机记录信息的要求,提供时间、地速、高度等信息,以便控制相机的工作参数并记录相关信息,完成对航空相机性能的测试。 相似文献