Investigating the accuracy of evolventometers

Conclusions The measurement results indicate that for checking measuring wheels which are used as standards for grade 5 and 6 wheels (according to GOST 6512-58), as well as for checking involute cams, it is necessary to produce new evolventometers whose kinematic chain must be simple, for instance, as in the Fellow disc instruments. It is also necessary to develop a more reliable method of setting the measuring tip for a given radius of the basic circumference, avoiding the method of setting it by touch.Such instruments are urgently required by the Committee's metrological institutions and plants which are manufacturing high precision wheels, as well as for checking involution cams designed for checking evolventometers.     

Reference trimmer disc capacitor for frequencies up to 200 Mc

Conclusions The above disc capacitor can be used for various purposes as a reference single-valued effective capacitance, or as a many-valued capacitance set at will to any value within its range, for testing or research purposes.The KVCh-8M capacitors are particularly convenient for determining the frequency characteristic of effective capacitances of other capacitors by the substitution method. In this method the measured capacitor is replaced at the high frequency by the KVCh-8M capacitor, which is set to the appropriate value by adjusting the distance between its plates.The preliminary adjustment is made with the capacitor screen removed, and the final adjustment through the opening in the screen.The actual capacitance of the disc trimmer is then calculated from (4) having measured its capacitance on a low-frequency bridge. Such a method of checking capacitors is very simple, since it does not require any accurate high-frequency capacity measuring devices. It is quite sufficient to have any type of Q-meter.     

Method for automatic and accelerated testing of moisture content in solid fuels

Conclusions The majority of the above methods suffer from serious defects. The preparation of average samples (selection, separation, crushing, etc.) is very labor-consuming, requires much additional time, and makes remote control of moisture in solid fuels impossible. Therefore, such methods are, as it were, transitional to methods of an improved type.The method of infrared radiation (for instance, of the Scientific Research Institute for Coal Preparation) will undoubtedly find a wide application providing its automation is extended.It should be noted that methods of measuring the electrical characteristics of fuel which form the basis for automatic remote control systems for measuring moisture encounter considerable difficulties in connection with the nonuniformity of fuel used in production. In this connection the method of automatic moisture measurement in flows of the material deserves particular attention.The work in producing methods and equipment for automatically checking moisture in solid fuels must be considerably extended, since various branches of industry are in urgent need of such equipment.     

Measurement of high dc voltages by means of an electron-diffraction camera

Conclusions The above technique and the cited examples for computing the voltage from electron-diffraction patterns of NaCl show that it is already possible to measure by means of an electron-diffraction camera éG-100 A high dc voltages up to 100 kV with an error of 0.1–0.2% For certain specimens whose electron gun can withstand voltages up to 120–150 kV the maximum measurement range is extended accordingly. Therefore, the above method of measuring high dc voltages can be used for checking high-tension instruments, including electrostatic kilovoltmeters. Moreover, the same method can be used for measuring the ratios of high-tension dividers directly with the operating voltages across them, which could not be done so far. In measuring the ratio of dc dividers by comparing them with reference resistors at low voltages it is impossible to evaluate the errors due to the heating of resistors by the operating current, to corona discharges, to leakages and space charges along the surface of the divider.The utilization for these purposes of an absolute method which consists of measuring high voltages by the diffraction of electrons raises the reliability of test results and undoubtedly will be of interest for practical application.     

Apparatus and Method for Checking the Reception Indicators of Global Navigational Satellite Systems

Methods and equipment are described for measuring the parameters of radio-navigational apparatus and for checking it at different stages of its development and production. Several components in the error of measuring the coordinates and the spatial orientation of an object are considered.     

三坐标数控机床精度检测与误差补偿

介绍了利用激光干涉仪检测和辨识数控机床几何精度的方法,建立了基于激光干涉仪的三坐标数控机床几何误差的数学模型．在准确掌握三坐标数控机床几何误差的基础上,利用所开发的误差补偿软件进行了误差补偿实验．结果表明,经过误差补偿,数控机床的加工精度可以明显提高．     

Additions to the rules for checking meters of thermal energy and hot water

The necessary additions to the rules for checking instruments for measuring thermal energy and hot water are considered. The impossibility in principle of interchanging them, based on the results of checking, is emphasized. The requirements imposed on thermal power meters and their units when delivered for checking and on the accompanying documentation are formulated. The rules for checking and selecting matched pairs of thermal converters of resistance and the rules for adjusting and selecting matched pairs of electromagnetic flow meters are presented. Translated from Izmeritel'naya Tekhnika, No. 8, pp. 45–48, August, 1999.     

Application of the differential calorimeter in magnetic measurements

Conclusions The calorimetric method of measuring losses in ferromagnetic materials can be used as a control method for checking the accuracy of measuring devices and for checking magnetic characteristics of materials at high frequencies under laboratory conditions (at plants producing magnetic materials) and in research institutes. This method is the most reliable when the voltage or current waveform are distorted, since the measurement results are almost completely independent of frequency.The differential calorimetric system provides measurements of small losses in ferromagnetic materials at high frequencies with great precision. Measurements of a power greater than 5 mw in a stable state condition and a completely balanced system can be made with an accuracy of the order of ± 1%. The sensitivity at the same time can be sufficiently high (the threshold of sensitivity in our case amounts to approximately 0.005 mv).     

Obtaining a given phase shift between voltages by the beating method

Conclusions The tests carried out by us have shown that it is possible with the above beating method circuit to set a given phase difference between voltages with an error not exceeding 0.1–0.3°, providing the described precautionary measures are observed. The above method can find wide application in producing reference phase-difference generators used for checking electronic phasemeters.The majority of phasemeters intended for measuring phase differences between two voltages have a linear scale and incorporate devices for setting the zero value of the phase. In such meters only the linearity of their scale need be checked. This circumstance makes considerably less stringent the requirements for the identity of the phasedifference generator amplifying channels, since the setting of the zero value of the phase can be made by means of the tested phasemeter.If the output of one of the channels is fitted with a calibrated potential divider it also becomes possible to use the device for measuring voltages by the compensation method.Phase-difference generators with a continuous adjustment of the phase angle in a given frequency range can be used widely not only for testing purposes but also for measuring phase characteristics of amplifiers, filters, and other radio equipment, as well as for adjusting components of tracking systems, computers, and other automatic equipment.     

Metrological problems in automatic production

Conclusions In order to ensure the successful development and application of automatic systems and, in the first place, high quality for their production, it is necessary to carry out a large amount of metrological work which has not been previously performed by the State Committee's system in working out theoretical foundations and methods of normalizing metrological characteristics of measuring instruments for automatic control, regulating and monitoring systems; in developing methods and equipment for testing and checking measuring devices of automatic system; and in carrying out state testing of automatic measuring systems.The State Committee and its agencies should in future provide metrological evaluations of control, regulation and monitoring systems as a whole.     

Evaluating the bandwidth of an if amplifier in a superheterodyne attenuation meter

Conclusions A superheterodyne attenuation meter, the bandwidth of whose IF amplifier is selected to reduce the random error in measuring a given maximum attenuation, provides smaller random and systematic measurement errors than a meter the bandwidth of whose IF amplifier is selected to provide equal random error components due to frequency instability and thermal noise. Errors in measuring low and medium attenuations will also be smaller with the above method of selecting the IF amplifier's bandwidth, i.e., this bandwidth will be optimum.Translated from Izmeritel'naya Tekhnika, No. 5, pp. 29–31, May, 1967.     

用三坐标仪检测两圆柱轴线定向误差

三坐标测量仪通用测量软件可对两圆柱轴线定向误差进行检测,是一种新研制的快捷精确的测量方法,可广泛用于各类工件两圆柱轴线的平行度、垂直度及倾斜度误差检测,工件可任意摆放,对大型工件测量显得更方便。     

NiTi形状记忆合金丝焊接性研究

采用Ｐ１０５－９Ａ精密时间控制交流点焊机进行了ＮｉＴｉ形状记忆合金细丝的十字搭接焊。通过焊接接头的力学性能测试和热影响区宽度与内部组织的结果表明，采用电阻点焊方法，焊接部分的抗拉强度可达母材抗拉强度的９０％以上，接头内部没有或只有少量的铸态组织，热影响区宽度为０．２８ｎｍ文中还对焊接接头进行了变形恢复试验，接头的形状恢复率可达９８％以上。     

New equipment for checking heat-power instruments

Summary The first specimens of the described apparatus were produced by the Etalon Plant of the VNIIM in high-temperature performance, and they were thoroughly tested. Thanks to their compactness, convenience in operation, and high checking accuracy, the apparatuses will undoubtedly find a wide application in the laboratories of the Committee system and in control laboratories of metallurgical plants.The process of testing with both apparatuses is considerably speeded up thanks to a rational selection and arrangement of standard measuring instruments built into the apparatus, switching and regulating devices, and also thanks to the application of the semi-automatic standard R2-A potentiometer ZIP model.According to sources in literature, an apparatus for testing secondary instruments has not been developed abroad.The drawings of the apparatus are presently being handed over to a number of organizations in order to bring about its production in series.     

DEA based models for reallocations of police personnel

A difficult aspect of improving the efficiency of service organisations in the developed world is the need to lay-off experienced people, whose training had significant costs and where later replacements are both costly and time consuming. This paper shows a novel way to reallocate personnel resources between tasks within a specific unit as well as between similar units using a data envelopment analysis model set. As there are many different ways to reallocate people, we propose six different scenarios to provide for different circumstances or policy objectives that may exist in the organisations. The method is illustrated using police units in a major metropolitan area and the results herein illustrate how efficiency improvements can be made in the police units’ operations with very different impacts on the people involved for the various scenarios. This method saves resources and improves operating efficiency while allowing management to consider or compare the results following from different objectives. In some cases it may also preserve morale amongst the personnel, when the necessary productivity and efficiency improvements are made in ways that specifically aims at also minimising the impact on the personnel.     

An Impedimetric‐Fluorescence Double‐Checking Biosensor with Enhanced Reliability Based on Graphene Oxide

MicroRNA (miRNA) is a class of clinically significant diagnostic and prognostic markers for some diseases, especially for cancer. Graphene oxide (GO) has been reported to bind and quench dye‐labeled single‐stranded DNA (ssDNA) probes while it has less affinity toward double‐stranded DNA (dsDNA) or hybrids of DNA/RNA. This property makes it very suitable to construct a double‐checking system for miRNA detection, thus increasing the reliability of detection. This kind of double‐checking sensor will have great potential in clinical diagnosis. Based on this concept, in this study a simple and sensitive electrochemical impedance spectroscopy biosensor for miRNA‐21 is developed using a GO‐coated electrode. Simultaneously, the fluorescence of the remaining hybridization solution which contains dissociated duplex of ssDNA/miRNA is also investigated to double check the signal and increase its reliability. Therefore, a GO‐based double‐checking biosensor is developed for miRNA‐21 detection, which shows simplicity, high sensitivity and selectivity, and outstanding reliability. This is the first time to integrate the electrochemical impedimetric method and fluorescence method in one sensing system for detecting miRNA based on GO. It is believed that this work will have a profound impact on the design of graphene‐based biosensors for miRNA detection.     

Computerized Primary Standard Equipments for Metrological Support to Energy Resource Meters

Metrological support is considered for working means of measuring variable pressure differences, flow rates, and volumes of liquid and gases in commercial energy resource meters. A set of computerized standard equipments has been set up for testing, calibrating, and checking differential pressure sensors as well as gas and water meters.     

Indicators of sustainable production

The main cause of environmental damage is unsustainable production and consumption, especially in industrialized countries. Achieving sustainable development will require changes in industrial processes, in the type and quantity of resources used, in the treatment of waste, in the control of emissions, and in the products produced. One of the difficulties in measuring the company's level of sustainability is to determine which directions of change are leading towards sustainability. Hence, it is necessary to apply appropriate metrics that will enable these assessments. This paper presents indicators for assessing and promoting business sustainability—indicators of sustainable production. It first introduces the main concepts of such production and a set of necessary conditions that firms must fulfill in order to be sustainable. It identifies major functions of indicators and it proceeds to presenting the role of indicators.The paper focuses on sustainable production, proposing indicators of sustainable production, which could be used as strategic metrics for assessing the sustainability level of a company and for identifying more sustainable options for the future. They enable a large amount of information to be compressed into a format easier to manipulate, compare and understand. The proposed indicators focus on the environmental aspect of sustainable production. However, to achieve sustainable production, a company should incorporate social and economic indicators as well. Most of the indicators included can be applied across industry. However, they are not aimed at being uniformly applicable to all sectors. According to the flows in the manufacture they are divided into input and output indicators and they are based on commonly measured environmental aspects of sustainable production (energy use, materials use, water consumption, products, wastes, and air emissions) covering key global issues. The paper represents a new approach to the systematization of indicators and their symbols and units.List of symbols UP Unit of production (e.g. mass in t or kg, volume in m³, number, monetary value in EUR, etc.) - PO Production output     

A new method for the placement of buffers in serial production lines

The placement of buffers in a production line is an old and well-studied problem in industrial engineering/operations research that is still relevant today. Decisions regarding the amount and placement of buffers in a production line occur repeatedly in system design. In this paper we document a new buffer placement method for serial production lines that operate under a variety of assumptions. The method uses information generated in a production line simulation, whose conceptual representation of job flow and workstation interaction can be described with a network, to place buffers in order to maximise throughput. This buffer placement method is very efficient and can be implemented in a spreadsheet. We demonstrate the effectiveness of the method by comparing our results against those produced by a genetic algorithm for buffer placement. Experiments are conducted on a variety of test cases. This new buffer placement optimisation method will permit designers to quickly and effectively evaluate many design alternatives and thus improve final production system performance.     

某商业楼溶液调湿新风机工况和经济性分析

依据某工程溶液调湿空调系统设计实例,探讨了新风送风状态点的校核方法,在送风状态点达到极限值的情况下可以校核室内状态点是否满足要求。由机组的工况校核发现,重新配置压缩机的大小或采用变频方式,能达到节约初投资和节能的目的。两种新风机组方案的比较结果显示,溶液调湿新风机运行费用有明显优势。