基于T-S模糊模型的TDR土壤水分传感器标定方法研究

利用TDR土壤水分传感器实现土壤水分数值的精确采集具有现实意义。为了获得TDR土壤水分传感器水分含量测量所对应输出电压与实际土壤含水量的良好对应关系，在采用取土实验测量法获得实际水分含量数值与对应输出电压数值的基础上，利用Takagi-Sugeno模型逼进精度高、后件参数线性化等优点。对TDR土壤水分传感器标定曲线进行分段线性建模，获得良好的标定模型，为土壤水分的精确实时测量提供了依据。

头部相关传递函数获取关键技术研究

虚拟现实技术(VR)的飞速发展使双耳听觉研究越来越深入,如何快速准确地获取个性化头部相关传递函数HRTF成为研究热点。介绍了HRTF获取关键技术研究现状,总结出HRTF的4种获取方式:实验测量法、数学建模法、数据库匹配法和主观选择法,并阐述各方法的基本原理。将各方法进行对比,指出HRTF获取工作中需解决的问题和未来研究方向。

对不同水平篮球运动员部分认知能力的比较研究

通过文献资料法、实验测量法对篮球运动员的认知能力进行研究。结果表明,不同水平运动员之间"硬件"指标上不存在显著性差异,这说明运动员对篮球运动特殊信息的加工能力才可能是区分运动员技能水平的关键,它是以运动员的知识、经验、技能为基础的。

开关磁阻电机磁链特性检测方法综述

对开关磁阻电机现有的磁链特性检测方法进行了综合评述。开关磁阻电机磁链特性检测是其电机特性研究中的重要环节,获取准确的磁链特性是实现电机高性能控制的重要前提。磁链特性检测方法有2种,即有限元分析法和实验测量法。有限元分析法因其检测精度和计算烦琐程度之间存在矛盾,在实际中难以得到实现;实验测量法包括直接测量和间接测量,间接测量因其自身具有操作实施简单、检测精度高等优点得到了广泛应用。伴随着人工智能技术的不断发展,现在国内外学者将越来越多的智能算法应用到磁链特性检测中去。

Effect of Stirring on Oil-Water Separation in Rare Earth Mixer-Settler

Oil-water separation is critical to solvent extraction process of rare earth, which can directly affect the yield and quality of the product. The experiments measure the two-phase separation time in a beaker, mixing uniformity of two phases in the mixer and the oil phase entrainment at oil exit by the Karl Fischer method and numerical simulation for the mixersettler to study the combined effect of gravity and stirring. Experimental results show that relative to the static situation, the separation efficiency resulted from low-speed stirring is increased by 25%. The water content in the oil is a minimum at an offset distance L of 10 cm and the clearance off the tank bottom z of 10 cm is as low as 0.49%. Distribution images of oilwater separation at 2 s indicates that stirring is very conducive to the separation of the oil-water phase.

Developments in the understanding of gas–solid contact efficiency in the circulating fluidized bed riser reactor:A review

In the last several decades, circulating fluidized bed reactors have been studied in many aspects including hydrodynamics, heat and mass transfer and gas–solid two phase contacting. However, despite the abundance of review papers on hydrodynamics, there is no summary paper on gas–solid contact efficiency to date, especially on high density circulating fluidized beds(CFBs). This paper gives an introduction to, and a review of the measurement of contact efficiency in circulating fluidized bed riser. Firstly, the popular testing method of contact efficiency including the method of heating transfer experiment and hot model reaction are discussed, then previous published papers are reviewed based on the discussed methods. Some key results of the experimental work are described and discussed. Gas–solid contact efficiency is affected by the operating conditions as well as the particle size distribution. The result of the contact efficiency shows that the CFB riser is far away from an ideal plug flow reactor due to the characteristics of hydrodynamics in the riser. Lacunae in the available literature have been delineated and recommendations have been made for further work.

Hydrodynamic Performance of Multiple-Row Slotted Breakwaters

This study examines the hydrodynamic performance of multiple-row vertical slotted breakwaters. We developed a mathematical model based on an eigenfunction expansion method and a least squares technique for Stokes second-order waves. The numerical results obtained for limiting cases of double-row and triple-row walls are in good agreement with results of previous studies and experimental results. Comparisons with experimental measurements of the reflection, transmission, and dissipation coefficients （CR, Cr, and CE） for double-row walls show that the proposed mathematical model adequately reproduces most of the important features. We found that for double-row walls, the CR increases with increasing wave number, kd, and with a decreasing permeable wall part, din. The Cr follows the opposite trend. The CE slowly increases with an increasing kd for lower kd values, reaches a maximum, and then decreases again. In addition, an increasing porosity of dm would significantly decrease the CR while increasing the Cr. At lower values of kd, a decreasing porosity increases the CE, but for high values of kd, a decreasing porosity reduces the Ce. The numerical results indicate that, for triple-row walls, the effect of the arrangement of the chamber widths on hydrodynamic characteristics is not significant, except when kd〈0.5 Double-row slotted breakwaters may exhibit a good wave-absorbing performance at kd〉0.5, where by the horizontal wave force may be smaller than that of a single wall. On the other hand, the difference between double-row and triple-row vertical slotted breakwaters is marginal.

Technique and experiment of active direct gas pressure measurement in coal roadway

An active measurement method and its principle was introduced consideringthe low success rate,special difficulty,and long measurement time of the direct gas pressuremeasurement currently used in coal roadways.The technology of drilling,boreholesealing depth,borehole sealing length,sealing control of the measuring process,compensatorycomputation of gas loss quantity and other key techniques were discussed.Finally,based on the latest instrument the authors developed,a series of experiments of directgas pressure measurement in the coal roadways of the Jincheng and Tongchuanmine district,were carried out.The experimental results show that active gas pressuremeasurement technique has advantages as follows:(1) the application scope of direct gaspressure measurement technique is wide and it does not have the restriction of coalhardness,coal seam fissure and other conditions;(2) the measured results are credible,which can be tested by the same gas pressure value acquired from a different borehole inthe same place;(3) the measurement process is convenient and quick,it takes about 2 to3 days to acquire the gas pressure value in a coal seam.

Methodology for Determination of Moisture Distribution

The aim of the research is to determine the capillary conductivity coefficient as a characteristic material moisture parameter of the building materials using a non-destructive method while using microwave radiation. Available documents are usually focused on the description of diffusion and similar works are based on the difference of partial pressure [I]. Publication will introduce experimental measurements the transport of humidity in porous material in a non-stationary state. As a result may be obtaining of data for formulation of humidity profiles with the help of experimentally built measuring apparatus without influence of human factor. Aim is verification of mentioned method of measurement for description of moisture parameters building materials applicable for practice. Complication in the determination of moisture parameters is various porous textures and the remains effect of condensation and transport influence of liquid moisture by diffusion in porous material. At the present time does not exist for standard use computational theory to description of transport of dampness in building materials. Moisture in porous medium is transported by the help of the capillary forces. The liquid moisture gradient is an indicator of moving of liquid moisture in a porous material through capillaries. This phenomenon is called capillary conductivity of moisture. Purpose presents measurement of material specimen for formulation of capillary conductivity coefficient and its dependence on moisture. The specimen of porous material is subjected to an isothermal moisture intake process. The transient moisture distribution in the specimen during the process is determined, at different stages of the process. Methodology of data scanning with the help of microwave radiation and data processing is processed for numerical computation on the basis known physics laws. The outputs of measurements can be used for evaluation of physical properties of building materials.

Measurement method and experimental research on flame emissivity in coal-fired furnaces

The combustion condition in coal-fired furnaces of the large power station boiler is very complex and the flame emissivity is one of the important combustion parameters. A measurement method of the flame emissivity based on the blackbody furnace calibration of CCD （Charge Coupled Device） cameras and the color image processing techniques of computer was introduced. The experimental research on the flame emissivity in a 200 MW boiler furnace and a 300 MW boiler furnace was conducted respectively through the several CCD cameras installed at different height in furnace. The measurement results show： the flame emissivity increases with the increase of the unit load, the flame emissivity of the burner areas in furnace is the highest and the flame emissivity decrease with the increase of height of furnace above the burners area.

Damage detection of frames using the increment of lateral displacement change

The method proposed in this paper is based on the fact that the damage in different types of structural members has distinctive influence on the structural stiffness. The intrinsic mechanical property of the structure is tapped and fully utilized for damage detection. The simplified model of the flexibility of frames treats the individual storeys as springs in series and the frame as an equivalent column. It fully considers the main deformation of all beams and columns in the frame. The deformation property of the simplified model accorded well with that of the actual frame model. The obtained increment of lateral displacement change (IOLDC) at the storey level was found to be very sensitive to the local damage in the frame. A damage detection method is pro- posed using the IOLDCs as the damage identification parameters. Numerical examples demonstrate the potential applicability of this method.

Rayleigh Scattering Experiment for the Measurement of Hydrogen Cluster Size

The hydrogen clusters are produced at liquid nitrogen temperature in a supersonic adiabatic expansion of moderate backing pressure gases into vacuum through a Laval nozzle and their averaged size are measured by Rayleigh scattering. The average cluster size N^-c is about 250 hydrogen atoms at a backing pressure 1.0 MPa in these measurements.

Laboratory and field experiment on measurement of soil thermal conductivity by probe method

The authors presented a new measuring method of the soil thermal conductivity,the probe method,which is designed and made based on the theory of line heat source. This method is used to measure thermal conductivity of coarse sand,fine sand and silty clay in different water contents. The results that measured by the probe method are well consistent with those of QTM-D_2. The soil thermal conductivity increases in different levels with the increase of the water content. Compared the soil thermal conductivity measured by the probe method in laboratory with in-situ experiment,it shows that the measuring gap gradually increases with the increase of the depth. The reason is that the in-situ measuring thermal conductivity can reflect the actual situation of the soil mass.

Verification of Insulation Oil Reclamation by Turbidity and Spetrophotometry Measurements

Oil reclamation with Fuller＇s earth is known to have an improved effect on conditioning aged oil. In this paper it is shown that aged oil reclamation effectiveness can be monitored with turbidity and spectrophotometry measurements. These low cost testing techniques offer a useful tool to quantify the effect of Fuller＇s earth. Experimental investigations performed in laboratory conditions have shown that the quality of properly reclaimed aged oil can compete with that of new oils. Thus, in addition to extending the life cycle of this non-renewable resource, on-line reclamation of liquid might also prevent the premature ageing of paper insulation. Studying the stability of reclaimed service aged oil samples emphasized the important role played by Fuller＇s earth absorption capability.

浮力问题解题的若干思路

1、利用基本概念、原理求解浮力问题1.1 实验测量法求解浮力例1 如图1所示,在甲图中,物块有四分之一体积没入水中,弹簧秤的示数为14.7牛,在乙图中。

Heat transfer blockage in small scale combustion of polymers

Flame heat transfer blockage occurs as fuel vapors, soot and products of combustion near a burning fuel surface block much of the heat feedbacks （including external radiative heat flux） to the fuel surface of a burning object. Blockage clearly affects burning rates and heat release rates of fires. This needs to be included when calculating flame heat transfer in fire growth models. An understanding of bttrning of materials in small scale fires is of broad and vital importance for predicting their burning performance in large scale fires. The blockage phenomenon was clearly observed and quantitatively measured in experiments that took advantage of the unique capability of the Fire Propagation Apparatus （FPA） of being able to vary the ambient oxygen concentrations. An indirect measurement approach was established which provides an experimental understanding of the concept of the blockage. The measurements were further explained by a one-dimensional steady-state model of a diffusion flame, which focuses on the radiant absorption and emission by the gas-soot mixture of flames. The theoretical model provides a greater understanding of the fundamental knowledge of the blockage. The overall heat transfer blockage factor can be up to 0.3 -0.4 for PMMA and POM. The factor and its components are nearly independent of the external radiation, but increase as the ambient oxygen concentration rises. A comparison between experimental data and model prediction shows a good agreement.

Experimental study of the optical fiber characteristics by digital hologram

The characteristics of optical fiber are quite important for improving the performance of optical fiber communication and sensor systems.Based on the Mach-Zehnder interferometer,a new measuring method is proposed and the digital holograms between the single mode fibers(SMFs) and specialty double-cladding(DC) fibers are analyzed.The experimental results show that the fringe density can be changed under the conditions of coaxial and off-axial interferences.Therefore it can be used to analyze the optical fiber characteristics including refractive index distribution,fiber modes,phase difference,etc.