自动测试系统视情计量保障方法研究

针对传统计量保障方式容易导致不足计量和过剩计量的问题,提出了自动测试系统的视情计量保障方法.规划了自动测试系统的视情计量保障体系;进行了自动测试系统的溯源性设计;分析了校准数据的特征;建立了校准间隔优化模型;并且在两次校准间隔期内采用测量过程控制方法,全面监控自动测试系统的量值状态.实验表明,自动测试系统的视情计量保障在一定程度上缓解了不足计量和过剩计量的矛盾,提高了计量保障效率.     

自动测试系统自动计量方法探讨

针对自动测试系统的计量保障需求,提出了自动测试系统校准规范,为实现自动测试系统的校准提供技术支持,提出了完整的自动测试系统自动计量方法,从计量角度解决了ATE系统如何计量这一难题,并结合实例进行了初步研究.该方法新颖易行,可在各种ATE系统的计量保障中推广应用,对测试系统计量保障的进一步研究和实施有积极作用,具有较高的理论价值.     

自动测试系统自校准与统计控制分析

本文详细介绍了装备自动测试系统(ATS)的组成及其自校准结构特点与自校准计量保障的控制过程,并采用线性拟合方法对测量数据进行分析与预测,实现了校准间隔内自动测试系统组成与参数计量性能的检测。     

自动测试系统完全计量的研究与实现

针对目前自动测试系统计量存在的缺陷,提出了自动测试系统完全计量的新概念,自动测试系统的完全计量是指考虑影响自动测试系统技术指标的所有因素,全面计量自动测试系统,包括系统软件的可靠性评估、传统仪器的计量检定、虚拟仪器的计量校准和专用模拟器的计量测试,并详细论述.可以在各种基于虚拟仪器技术的自动测试系统中推广应用,对于提高...     

军用自动测试系统装备计量保障的深入研究

在深入了解自动测试系统结构的基础上,提出了三种装备计量保障策略和三种装备计量保障方法,可以在各种自动测试系统中推广应用,对于规范自动测试系统的装备计量保障具有重要意义。     

DAM自动测试系统校准

正数字阵列模块(Digital Array Module,DAM)自动测试系统为DAM的研制、生产验证、维修保障提供了重要手段。从功能角度看,DAM自动测试系统等效于一台综合测试仪表,而作为仪表就必须进行计量校准。目前,国内专业测试系统校准没有统一的解决方案,基本是采用离位和手动校准,用仪表的校准结果衡量系统,而未考虑系统实际工作状态和环境,导致用户无法真正了解系统的准确性。作为一种测试系统,其本身的准确性与可靠性将直接影响整个测试过程,自动测试系统的校准是保证测试准确度的重要前提,必须引起足够重视。     

基于虚拟仪器的某导弹测试系统自动校准设计与实现

针对基于虚拟仪器的某导弹自动测试系统,研究了通用测试接口上信号的自动校准方法和实现方案,通过采用程控开关和CPLD等技术途径,解决了大量复杂信号的测量溯源性问题,提高了计量保障工作效率.     

DAM自动测试系统校准

DAM自动测试系统是DAM关键测试设备,它的性能会对DAM的性能有直接的影响,为了解决系统校准不全面和自动化校准不高的问题,提出了原位校准思路。该文通过对DAM自动测试系统原理和工作过程的分析,建立了DAM自动测试系统校准装置,阐述了校准适配网络原理组成和软件组成框图。经过实际应用证明,该方法通用性好,自动化程度高,满足DAM自动测试系统校准需求。     

基于灰色马尔柯夫预测的测量仪器校准间隔动态优化

根据测量仪器校准参数数据特点，建立了仪器校准参数动态发展趋势的时间序列组合模型。将灰色预测与马尔柯夫预测方法优化互补，用灰色预测模型预测参数总体发展趋势，在此基础上采用马尔柯夫模型预测参数在总体趋势下的随机波动性变化，得到校准参数发展趋势预测模型的解。给出基于校准参数趋势预测的校准间隔动态优化方法，并通过实验数据对预测模型进行了验证。结果表明，此模型既能预测校准参数总体趋势，又适合于波动性较大的随机序列变化；校准间隔的优化改善了计量管理中不足计量和过剩计量的缺陷。     

自动测试系统溯源性设计方法研究

针对自动测试系统的计量保障需求,提出一种自动测试系统溯源性设计方法.根据溯源性设计的原则,规划了自动测试系统的溯源体系,阐述了溯源性设计的内容.通过溯源参数优化算法,实现了自动测试系统对外溯源参数的最小化,系统内部形成了合理有效的溯源链.在某型自动测试系统研制中应用溯源性设计方法,取得了良好的效果.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.