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中小企业质量管理体系建立方案初探 总被引:1,自引:0,他引:1
郭文君 《西安航空技术高等专科学校学报》2006,24(2):38-39
目的 中小企业为确保产品质量,就必须建立起科学的质量管理体系。方法 将影响质量管理的各个要素和工作流程通过科学、严密的程序加以控制,持续改进。结果 通过各种控制增强全员的质量意识,品牌意识。结论 产品质量维系着企业的生命,只有建立起科学的质量管理体系,企业才能发展和壮大。 相似文献
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软件自动生成技术在测试上的应用 总被引:1,自引:0,他引:1
作为CAT工作站的软件平台,可视化自动测试环境(简称VATE)的应用对提高测试软件开发效率和测试系统中PC资源的充分利用有不可估量的作用。本文介绍了一种在Microsoft Windows平台上开发测试软件自动生成环境的方法,即通过组建仪器驱动器库,利用结构化的流程设计思想来实现测试软件的生成。 相似文献
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Hypersonic glide vehicles (HGVs) are launched by a solid booster and glide through the atmosphere at high speeds. HGVs will be important means for rapid long-range delivery in the future. Given that the glide is unpowered, the initial glide conditions (IGCs) are crucial for flight. This paper aims to find the optimal IGCs to improve the maneuverability and decrease the con- straints of HGVs. By considering the IGCs as experiment factors, we design an orthogonal table with three factors that have five levels each by using the orthogonal experimental design method. Thereafter, we apply the Gauss pseudospectral method to perform glide trajectory optimization by using each test of the orthogonal table as the initial condition. Based on the analytic hierarchy process, an integrated indicator is established to evaluate the IGCs, which synthesizes the indexes of the maneuverability and constraints. The integrated indicator is calculated from the trajectory opti- mization results. Finally, optimal IGCs and valuable conclusions are obtained by using range anal- ysis, variance analysis, and regression analysis on the integrated indicator. 相似文献
117.
民机安全性分析的重要内容之一是系统运行过程分析,现有的运营安全性分析模型大多没有综合考虑人、飞机、运行环境等各类影响安全性的因素。本文综合考虑系统安全性分析功能间的时间、控制、资源、前提等影响,更加细致地分析影响系统安全运行的因素,建立了全面且规范化定量化安全性分析模型。运用功能可变性描述规则(RFV)、层次分析法(AHP)对功能共振分析法(FRAM)进行改进,建立民机系统安全性综合分析模型。使用模型还原143号班机安全运行所需条件,分析得出应重点防范的耦合变异与功能失效,且扩展了原事故调查报告结论,表明了该模型的可行性,提出的理论模型可为航空公司在运营系统安全性方面提供理论参考和技术支持。 相似文献
118.
《中国航空学报》2020,33(12):3526-3534
As one of the most important methods for machining process with high accuracy, ultra-precision grinding is widely used in fields such as aerospace, automotive and mold, etc. Simultaneously, it is common that wheel and spindle axis do not coincide with each other due to wheel settings, machining errors and so on. This could result in the generation of wheel runout, which may reduce the machining surface’s quality. In this paper, combining this phenomenon, an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory. After that, the accuracy of this method is verified. Two experiments are carried out on a 5-axis machining center. The artificial runout is set up and calculated utilizing the least square method. Finally, using the presented method, two examples with and without runout are introduced to illustrate the validation of the proposed model. The error due to the runout effect is also analyzed. 相似文献
119.
Application of time-variable process noise in terrestrial reference frames determined from VLBI data
Benedikt Soja Richard S. Gross Claudio Abbondanza Toshio M. Chin Michael B. Heflin Jay W. Parker Xiaoping Wu Kyriakos Balidakis Tobias Nilsson Susanne Glaser Maria Karbon Robert Heinkelmann Harald Schuh 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(9):2418-2425
In recent years, Kalman filtering has emerged as a suitable technique to determine terrestrial reference frames (TRFs), a prime example being JTRF2014. The time series approach allows variations of station coordinates that are neither reduced by observational corrections nor considered in the functional model to be taken into account. These variations are primarily due to non-tidal geophysical loading effects that are not reduced according to the current IERS Conventions (2010). It is standard practice that the process noise models applied in Kalman filter TRF solutions are derived from time series of loading displacements and account for station dependent differences. So far, it has been assumed that the parameters of these process noise models are constant over time. However, due to the presence of seasonal and irregular variations, this assumption does not truly reflect reality. In this study, we derive a station coordinate process noise model allowing for such temporal variations. This process noise model and one that is a parameterized version of the former are applied in the computation of TRF solutions based on very long baseline interferometry data. In comparison with a solution based on a constant process noise model, we find that the station coordinates are affected at the millimeter level. 相似文献
120.
介绍了对数字仪器标准装置实施期间核查的时机、核查方案的策划、核查的频次、核查的方法、核查的记录方式和核查结果的处理。运用同量级比对的核查方法,通过对数字仪器标准装置的直流电压、交流电压、交流电流三个参数期间核查过程数据的分析,建立控制图,取得了对测量标准实施期间核查的成果。 相似文献