位置参数的非线性函数的估计(英文)

本文研究位置参数的非线性函数的估计问题。应用均方误差直到三阶的渐近展开比较了通常使用的δ法、Jackknife法和Boatstrap法,并证明了,如果只考虑展开的前二阶,则这三种估计是相同的。这些估计的性质依赖于总体分布及非线性函数的具体形式。基于δ法,本文提出了一种新的估计,与已有估计相比,它具有较小的均方误差。     

Banach空间中渐近非扩张映像有限族不动点的混合迭代算法(英文)

Rounding errors often cause no convergence for an iteration sequence or result distortion in many fixed point iterative methods. In this paper, we study an iteration method with a random error, and establish the weak and strong convergence theorems for hybrid iteration method. The results extend Wang’s results from Hilbert spaces to Banach spaces, and extend Osilike’s results from a nonexpansive mapping to a finite family of asymptotically nonexpansive mappings in Banach spaces.     

加速新产品开发的有效手段——SE(同时工程)

同时工程是20世纪80年代初期,在美国汽车工业中兴起的一种行之有效的加速新产品开发的管理方法。它强调地了新产品开发的各有关环节的相关活动之间按时间加强配合和协调,以改进设计,工艺,提高效率,获得最低成本和要求的质量。介绍了同时工程与传统方法的主要区别,同时工程的具体内容,同时工程在我国工业企业中的应用与效果以及同时工程的发展。     

IEC 62059标准在智能电能表可靠性预计与考核验证方法上的应用(英文)

This article introduces the current situation of the smart meter’s reliability and the failure mechanisms at first,and then describes the relationship of meter reliability characteristics combined with its Bathtub Curve.It also introduces both the feasible failure tree model for meter lifecycle prediction based on actual experiences and meter reliability prediction methodology by SN 29500 norms based on this model.This article also brings forward that it is necessary that the "Learning Factor" shall be adopted in meter reliability prediction for new materials,new process,and customized parts by referring to GJB/Z299C.Thereafter,this article also tries to apply IEC 62059 and JB/T 50070 to introduce the feasible method for the lifecycle prediction result verification by accelerated lifecycle test.Furthermore,the article also explores ways to increase the firmware reliability in smart meter.     

修正的Szász算子同时逼近的点态估计(英文)

证明了定义在 [0 ,∞ )上的具有 s阶连续有界导数的函数可以用修正的 Sza′sz算子线性组合的 s阶导数逼近 ,得到了点态逼近的正定理和逆定理 .     

船舶防污漆加速试验方法研究

本文介绍了把防污涂料防污性能的静态实验和动态试验，动、静态渗毒率测试，ＳＰＣ型自抛光防污漆降阻性能测试，漆膜形态剖析等有机结合建立起的一套切实可行的加速试验方法和配套设施。采用该方法可在１年内评定出３年防污期效的防污漆。     

船体水上防锈漆体系加速试验方法研究

根据船舶水线漆和船壳漆的使用环境和主要破坏因素，设计了一套以盐雾－人工加速老化（紫外光／冷凝）交替暴露和带人造缺陷样板的加速暴露试验方法为主，结合海水冲刷、附着力等主要力学性能测定的试验方案。对８种国内外船体水上部份防锈漆体系的性能进行综合评定，其结果采用数字量化评分。试验结果表明，该试验方法可在相当短的时间内对各类船体水上防锈漆体系的综合性能作出正确的评定。     

聚合物基复合材料加速老化方法研究进展

概述了聚合物基复合材料加速老化研究方法的进展,从试验方法、老化机理等方面着重介绍了湿热老化、腐蚀侵蚀和人工气候老化,总结了高置信度、高可靠度评估复合材料工作寿命的方法,并展望了复合材料加速老化研究方法.     

原型体系的研究与产品族的设计方法探析

侧重于产品原型体系的研究,阐述了原型体系建立的原则以及提取的方法,对产品族的再设计提出了建议、指导;为以后中型企业产品开发提供有价值的帮助,并且提出找准企业产品的市场定位,坚持特色发展的观点.并且通过完整的设计实例,验证理论的科学性.     

Constant Stress Accelerated Life Test: Different Methods of Estimation Under the Exponentiated Power Lindley Distribution

Strength of Materials - Accelerated life testing has been used frequently in several fields as it provides an economical way for obtaining failure time data rapidly or in a shorter time as compared...     

A Source of Accelerated Metal Plasma Flow with Controllable Parameters

Technical Physics Letters - Parameters of the metal plasma flow generated by a source with heated liquid anode have been studied during motion in axial magnetic field. It is established that the...     

Accelerated weathering of UPVC

A detailed study has been conducted to assess the effect of various artificial weathering cycles on the degradation of three formulations of window-grade UPVC. The results were compared with samples which had been exposed outdoors in the north-east of England for periods of up to 16 years. Microhardness, loss of calcium carbonate filler, intensity of the C–O stretching band, colour and gloss were used as measures of degradation. The samples tested in the laboratory exhibited the characteristic surface degradation and partial recovery predicted for these materials. Cyclic variation of certain properties was exhibited for long laboratory exposures. In contrast, the naturally exposed material gave no definitive indication of a recovery process. The various measures of degradation employed gave reasonably consistent indications of degradation, particularly with regard to the onset of partial recovery. The complexity of the degradation process for these materials inherently limits the establishment of quantitative rate equations to predict the durability of naturally exposed materials. Nevertheless, four of the five exposure cycles gave consistent ranking of the different materials which compared well with the ranking deduced from natural exposure. An optimum artificial weathering cycle was derived. It is recommended that laboratory tests should involve testing of a reference sample in parallel for the purposes of quality control and interlaboratory comparison. By choosing a material with established outdoor performance, a basis for prediction of relative service life is also provided. This revised version was published online in November 2006 with corrections to the Cover Date.     

A review of computer-aided Simultaneous Engineering systems

World-wide markets are becoming increasingly competitive, and in order to sustain market share organisations are developing a customer-oriented approach for designing and producing high-quality, high-value products. The philosophy of simultaneous engineering has been proposed as a potential means of improving product development practice. This philosophy involves simultaneously satisfying the functionality, reliability, manufacturability, and marketability concerns of new products in order to reduce product development time and cost, and to achieve higher product quality and value. In this paper the concept, objectives and principles of simultaneous engineering are introduced. The past and present research into computer-aided systems for the support of simultaneous engineering is present, reviewed and classified. This will both allow the current state of the art to be assessed, and enable the identification of future research that will contribute to the realisation of computer aided support for Simultaneous Engineering.     

A Methodology for Selecting Representative Input Regions for Accelerated Testing

This article describes an approach to the methodology of selecting a representative region from the multitude of input influences based upon input (output) influences simulation. The result leads to successful accelerated testing. The concept of representative region selection is then extended to real-life analysis techniques to establish the characteristics of the critical input (or output) processes. This leads to the possibility of determining one field region that is a typical system characteristic of a wide variety of field influences. This methodology is described by four basic steps.