A new instrument for measuring surface pressure

A new instrument for surface pressure measurements using a floating-foil technique has been constructed. The instrument makes use of a probe in the form of a thin foil suspended at the gas/liquid or liquid/liquid interface tension. The present instrument has a dynamic range of 0.1-70 mN/m and a sensitivity better than 0.1 mN/m. Its speed of response is 50 ms but much faster measurements are possible. Measurements on behenic acid and cholesterol films on water and on a cerebroside film at a heptane/water interface are presented.     

A calorimetric probe diagnostics for neutral and charged components of a rarefied plasma flow

A procedure for diagnosing flows of nonequilibrium rarefied plasma using cylindrical and flat calorimetric probes also connected as a Langmuir probe has been developed. It is shown that this procedure can be used to determine the full set of local values of the main kinetic parameters for the neutral and charged components of a collisionless plasma flow.     

新型电磁式自动在线平衡装置

设计一种新型电磁式自动平衡系统,用电磁力代替配重校正不平衡质量,使平衡装置质量更小,精度更高,调整速度更快.使之在3000r/s转速下,能稳定工作,精度达到0.3μm,具有一定的工程实用价值.     

一种新型在线紫外光谱水质分析仪

介绍了一种自行研发的综合应用紫外光谱测量和智能计算技术的水质在线分析仪,并对其测量原理、硬件结构、软件功能与所采用的智能计算方法进行了详细说明。实际测量结果表明该水质分析仪操作简便,适合于连续在线水质分析和成批量水样检测。     

A method for identifying deuterons in the PAMELA satellite-borne experiment

The procedure of deuteron identification against the background of other particles in cosmic-ray measurements is described. The algorithm is based on measuring and comprehensively analyzing the particle rigidity, velocity, and ionization losses and allows discrimination of deuterons with an admixture of other particles of a few percent or less. This method has been developed in the course of the PAMELA experiment [1] with the magnetic spectrometer and the time-of-flight system.     

A new instrument for automated microcontact printing with stamp load adjustment

An instrument for automated microcontact printing (microCP) on microscope slides is described. The movement of the stamp, which is actuated by a computer controlled pneumatic actuator, is precisely guided until it makes contact with the substrate. As a consequence, the absolute position of the microprinted patterns is reproducible over a series of substrates with 1 mum standard deviation. Exchange of substrates and stamps is a quick and simple procedure. This makes possible the microprinting of adjacent or superimposable patterns, with different products, in a reproducible manner. Furthermore, a novel approach is described for adjusting the load on the stamp during contact. Two adjustable screws are set up so that their length (with reference to the substrate holder) limits the stamp compression during contact. The load on the stamp is proportional to the stamp compression and from the experimental point of view, this is controlled by the operator adjusting the screws. This makes possible the microCP with stamps incorporating large surface features as well as stamps with isolated features raised on the surface. For proof of concept, automated microCP of a single parallelepiped polydimethylsiloxane feature, with a surface of 2 cm x 30 microm and a height of 25 mum, is demonstrated inside a microfluidic channel without roof collapse. A second example is provided with a single cross feature, possessing an overall surface of 140 x 140 microm(2) and a height of 14 microm. Potential applications of this versatile, inexpensive and compact instrument are discussed. The machine's potential for high throughput also makes it suitable for mass production applications.     

一种风速模拟仪器的研制

各种测风传感器在出厂前,都要根据标准在测量范围内进行风速参数测试,以检验是否超差.通常采用模拟风速,然后将传感器的实测值和模拟值进行比对的方法.如何获得模拟风速,并能将模拟值与实际值比对,则是各种测风传感器风速试验所面临的关键问题.现根据螺旋桨式测风传感器每一定值风速对应风速轴一固定转速值的自身特点,设计研发了一种风速模拟仪器.该仪器是专为螺旋桨式测风传感器的风速测试检验所研制开发的一种装置.在做测试检验时,能够模拟风速和测得实际风速值,并能够实时显示.该仪器为智能化仪器,提高了检测效率,使风速测试检验具有实效性,比对性.且结构简洁、造价低、实用性强.     

A synthetic diagnostic for the evaluation of new microwave imaging reflectometry diagnostics for DIII-D and KSTAR

The first microwave imaging reflectometry (MIR) system for characterization of fluctuating plasma density has been implemented for the TEXTOR tokamak [H. Park et al., Rev. Sci. Instrum. 75, 3787 (2004)]; an improved MIR system will be installed on DIII-D and KSTAR. The central issue remains in preserving phase information by addressing antenna coupling between the reflection layer and the detector array in the presence of plasma turbulence. A synthetic diagnostic making use of coupled full-wave diffractive codes has been developed in geometries and applied to a variety of optical arrangements. The effectiveness of each scheme is quantitatively compared with respect to the fluctuation levels accessible in the simulation.     

Grating spectrometer system for beam emission spectroscopy diagnostics using high-energy negative-ion-based neutral beam injection on LHD

A beam emission spectroscopy (BES) system was developed for density gradient and fluctuation diagnostics in the Large Helical Device (LHD). In order to cover the large Doppler shift of the Hα beam emission because of the high-energy negative-ion-based neutral beam atom (acceleration voltage V(acc)=90-170?kV) and the large motional Stark splitting due to the large v×B field (magnetic field B=3.0?T), a grating spectrometer was used instead of a conventional interference filter system. The reciprocal linear dispersion is about 2 nm/mm, which is sufficient to cover the motional Stark effect spectra using an optical fiber with a diameter of 1 mm.     

A study on the design of a new power transmission for wind turbines

The single-rotor wind turbine remains the dominant design for energy production. However, this design requires improvements to overcome some of its limitations. The introduction of the dual rotor system regarded as improvement over the single-rotor system in Korea due to its high efficiency, despite Korea’s low wind quality. Many researchers have attempted to devise different dual rotor machines and assess their power production capabilities under similar wind conditions to those in Korea. Existing power transmissions for dual-rotor wind turbines have issues with the complexity of design, difficulty in manufacturing, high costs and low efficiencies. Therefore, the aim of this study was to design a new power transmission for the dual-rotor wind turbine with an alternative to the bevel-planetary system by using a planetary system. This new method is dependent on the torque ratio and not the gear ratio as in common gear systems. The design and analysis of each part, such as the gears, shafts, bearings and control mechanisms are included in this study. The design is based on the power transmission of a motor vehicle. A prototype of the design is manufactured to verify the proposed method. The experimental results show that the new planetary-type gear box incurs fewer energy losses, has a high efficiency and low manufacturing costs. It is anticipated that the proposed design might be suitable for use with commercial wind turbines.     

A new stylus instrument with a wide dynamic range for use in surface metrology

An instrument has been developed which can measure not only radius of curvature but also form deviation and surface texture at the same time. A computer is used to mathematically separate the form from the texture. The technique can be applied to the measurement of cross track curvature of bearing raceways and to other precision components whose form is defined as a circular arc, or a straight line, in which case angle will be measured instead of radius. The measurement of other forms such as parabolic, elliptical, hyperbolic and aspheric are the subject of continuing development. The instrument provides a distinctive and useful advance in measurement by the stylus method, offering possible solutions to many obdurate problems in the field of surface metrology     

A microwave two-wave interferometer for plasma diagnostics

The scheme and the main elements of an interferometer simultaneously operating at frequencies of the 8-and 4-mm ranges are presented. To combin e two radiations in a common waveguide section and separate them by sending to the corresponding receivers, a special separation filter has been developed. A homo-dyne technique for transferring phase measurements to an intermediate frequency is employed in the interferometer. The range of unambiguously measured phase shifts is 1.5°—360°, and the phase-shift measurement error is within 5%.     

A new way of cavitation diagnostics by measuring the emitted electromagnetic signal

A new method of cavitation diagnostics by measuring the electromagnetic undulation irradiated in the liquid permits many existing physical analyses in cavitation zones. At the same time, this method confirms the Frenkel theory of sonoluminescence which occurs in the liquid in the case of an intensive cavitation.     

'NODUS'-a sensitive new instrument for analyzing the composition of surfaces

A novel type of ion-scattering spectrometer for analyzing the composition of surfaces is described. By means of a specially designed cylindrical mirror analyzer the sensitivity of the instrument is increased by two or three orders of magnitude as compared with that of equipment used hitherto. The increased sensitivity allows analyses to be performed using extremely low ion doses. Under these conditions, destruction of the surface is negligible. The use of a differential pumping system guarantees UHV conditions at the target, thus minimizing contamination.     

国产傅立叶变换红外光谱仪研制动向——通用仪器向专用仪器的发展

用傅立叶变换红外光谱仪通用仪器配上专用软件包及特殊附件从而构成用在某些领域的专用仪器是近年来国产傅立叶变换红外光谱仪研制发展的新动向,本文介绍的几种专用仪器,具有测量速度快、准确度高、操作简便、价格便宜等特点。     

A new online delay estimation-based robust adaptive stabilizer for multi-input neutral systems with unknown actuator nonlinearities

This paper studies the problem of actuator-nonlinearities compensation in the multi-input uncertain neutral systems. The neutral systems with different unknown time-varying delays, unmodeled dynamics, nonlinear perturbations and disturbances are considered. A new methodology based on the online estimation of the delays to compensate for the effects generated by dead-zone and saturation, acting in series on a system's input are presented. The online estimations of the unknown delays are accomplished by adaptive laws that guarantee the exponential stabilities of the estimated delays. In the presence of state time delay, derivative state time delay, unmodeled dynamics, nonlinear perturbations, disturbances and both input dead-zone and saturation, the asymptotic stability of the closed-loop system is ensured and the state response converge to the origin. Finally, the practicability and the efficacy of the proposed approach is demonstrated via a numerical example.     

一种关于风电转盘轴承软带修形深度检测的新方法

针对风电转盘四点接触球轴承软带修形深度原来检测方法存在的问题,设计出一种新型检测工具与检测方法。该方法的检测数据与机床在线检测数据基本相同,说明该方法不仅可以准确检测软带修形深度,而且使用更加方便、快捷,更加适用于软带深度的检测。     

A new instrument for dynamic helical squeeze flow which superposes oscillatory shear and oscillatory squeeze flow

Simple shear flow has been widely used as a model flow system to investigate the rheological properties of complex fluids. Although it is useful and easy to apply, the shear flow is too simple compared with the complicated flows encountered in real processes. For this reason, it is necessary to study the rheological properties of viscoelastic fluids subjected to more complicated flow field. In this paper, we report a new instrument in which dynamic helical squeeze flow is generated. It superimposes the oscillatory squeeze flow on the oscillatory shear flow, and was designed to get more information on the microstructural change of complex fluids in the flow field which is more complex than conventional simple shear but is still well-defined. This instrument has advantages: the shear and normal stresses can be obtained simultaneously under the coupled flow field; the present design can be used to investigate the structural anisotropy in the direction of both rotational and vertical motion. This study provides a new design and methodology to investigate the rheological responses of complex fluids under dynamic helical squeeze flow.     

Contemporary instrumentation and application of charge exchange neutral particle diagnostics in magnetic fusion energy experiments

An overview of the developments postcirca 1980s in the instrumentation and application of charge exchange neutral particle diagnostics on magnetic fusion energy experiments is presented. First, spectrometers that employ only electric fields and hence provide ion energy resolution but not mass resolution are discussed. Next, spectrometers that use various geometrical combinations of both electric and magnetic fields to provide both energy and mass resolutions are reviewed. Finally, neutral particle diagnostics based on utilization of time-of-flight techniques are presented.