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2018 Vol. 39, No. 5 Published: 2018-09-22

	593	Research on Fractal Characterization of the Surface Morphology of Cu/Ti Nano Thin Film
		LIN Qi-jing,WU Hao,ZHANG Fu-zheng,WANG Chen-ying,JIANG Zhuang-de
		DOI: 10.3969/j.issn.1000-1158.2018.05.01
		Different composition and thickness of Cu/Ti films are fabricated by magnetron sputtering technology and their surface morphology are measured using atomic force microscope (AFM). The method of power spectrum is used to characterize the fractal morphology of the AFM height images. The results show that the Cu/Ti film surface morphology has multi-scale behavior and surface evolution in the whole and local area presents different scaling behavior. The high frequency section of the power spectrum for AFM image directly reflects the detail information of the surface while low frequency section reflects the complexity of the background region. There is an inevitable correlation between low frequency fractal dimension and roughness, because the change of low frequency fractal dimension can reflect the change trend of rough value Ra.
		2018 Vol. 39 (5): 593-597 [Abstract] ( 415 ) HTML (1 KB) PDF (912 KB) ( 565 )

	598	High-precision Probe for Measuring Micro-holes
		LI Rui-jun,XU Peng,TANG Shuai-tao,FAN Kuang-chao,CHENG Zhen-ying
		DOI: 10.3969/j.issn.1000-1158.2018.05.02
		The research and development of high-precision probes are described. A micro-hole measuring probe composed of a two-dimensional angle sensor, an elastic mechanism, and a homemade micro-spherical tungsten stylus is introduced. The stiffness and repeatability of the probe were verified by simulation and experiments respectively. The results show that the stiffness of the probe in three-dimensional directions is less than 0.4 mN/μm, the repeatability is better than 20 nm (k = 2). Finally, a practical measurement for a micro-hole with a diameter of approximately 420 μm was performed using the probe. The measurement results verified the practicality of the probe.
		2018 Vol. 39 (5): 598-604 [Abstract] ( 425 ) HTML (1 KB) PDF (1561 KB) ( 542 )

	605	High Efficiency Measurement Method for Large-size Aeroengine Blade Profile
		SHI Jian-hua,LIU Pan
		DOI: 10.3969/j.issn.1000-1158.2018.05.03
		A high efficiency surface measurement method based on coordinate measuring machine (CMM) is introduced. Based on the traditional large-size blade surface measurement method, a partition scanning method at variable speed of curvature adaptive was proposed. The optimized scan path can effectively solve the frequent probe replacement problem. To analyze the blade geometrical parameters, an over-scanning strategy was studied. The collected data were filtered by advanced programming and the complete blade profile closed curve was obtained by mathematical stitching. 40% of the measurement efficiency can be improved by this large-size blade measurement method, and it can ensure the measurement accuracy and completing the blade profile curve in the meanwhile.
		2018 Vol. 39 (5): 605-608 [Abstract] ( 396 ) HTML (1 KB) PDF (544 KB) ( 325 )

	609	Damage Parameter Calculation Based on 3D Point Cloud Mean Curvature Estimation
		ZHANG Yu-yan,QU Wen-han,GUO Quan-li,REN Rui
		DOI: 10.3969/j.issn.1000-1158.2018.05.04
		Aiming at the surface damage measurement of high speed sliding electric contact rail, a method of evaluating damage mass based on mean curvature estimation of 3D laser point cloud is presented. The laser scanner is used to obtain point cloud data which will be denoised, filtered, reduced, and k neighborhood searched. Next step of data processing is local quadric surface fitting, then the mean curvature of the point cloud data is estimated. The curvature threshold is set to achieve the extraction of feature point cloud to achieve damage area. According to detection results, the damage volume and mass loss are calculated. The experimental results show that the measurement precision can reach mg level. Moreover, the proposed approach is feasible and effective to measure the surface damage.
		2018 Vol. 39 (5): 609-614 [Abstract] ( 397 ) HTML (1 KB) PDF (1419 KB) ( 611 )

	615	A general pose testing method of industrial robot
		REN Yu,ZHANG Feng,GUO Zhi-min,SONG Zeng-chao,GONG Ting
		DOI: 10.3969/j.issn.1000-1158.2018.05.05
		A general pose testing method of industrial robot is proposed. The basic principle is to use laser tracker to measure the robot’s absolute pose indirectly by measuring 4 reference points fixed on its end, and to compare the real pose with the command pose to test the pose accuracy and repeatability. In this process, the reference points’ coordinates and the robot base coordinate system are calibrated synchronously by multi-pose constrain and a nonlinear calibration algorithm is designed. This testing method is illustrated with a KUKA KR210 R2700 industrial robot with a drilling end effector. The pose accuracy and repeatability of the robot are 0.3 mm and 0.06 mm, which are in accordance with the nominal index. And the coordinate deviation of the tool center point (TCP) from direct measurement is less than 0.015 mm. It is obvious that the testing method is accuracy enough for the requirements of robot pose testing and does not require special mechanical tools. The calibration residual is reduced to 0.35 mm by the nonlinear calibration method. It proves the calibration method has good robustness and can effectively reduce the error caused by inaccurate kinematics model of the robot.
		2018 Vol. 39 (5): 615-621 [Abstract] ( 421 ) HTML (1 KB) PDF (1520 KB) ( 887 )

	622	Adaptive Sampling Method of Surface Based on MKSA
		SUN Ying-bing,WU Feng-he,GUO Bao-su,FANG Guo-tao,LI Zhi
		DOI: 10.3969/j.issn.1000-1158.2018.05.06
		In view of the traditional sampling method of the on-machine measurement that the sampling points are too centralized and the sampling areas are omitted to influence surface profile, MacQueen K-means (MK) algorithm and simulated annealing (SA) algorithm were combined and the adaptive sampling method of complex surfaces for the on-machine measurement system based on MKSA algorithm was proposed. Through the absolute value of Gaussian curvature of the complex surface’s discrete point cloud data as the density function and the variance function as the convergence criterion, MK algorithm was used to generate centroidal voronoi tessellation(CVT). Besides, annealing criterion of the global algorithm of SA was used as cooling coefficient to improve the ability of the global optimization of the MK algorithm and the global optimal CVT was generated. The centroid of CVT was regarded as the measuring point and the distribution of measuring point on complex surfaces was accomplished which can fully reflects the curvature of the surface information. The simulation and experimental results showed that the distribution of sampling points of MKSA algorithm was more reasonable whose maximum deviation and average deviation of the fitting surface and the CAD model were less than the traditional methods. Therefore, the fitting surface of MKSA algorithm was more approximate to the theoretical surface of the CAD model.
		2018 Vol. 39 (5): 622-627 [Abstract] ( 378 ) HTML (1 KB) PDF (1586 KB) ( 472 )

	628	Overview of the 3D Profilometry of Phase Shifting Fringe Projection
		MAO Cui-li,LU Rong-sheng,DONG Jing-tao,ZHANG Yu-zhong
		DOI: 10.3969/j.issn.1000-1158.2018.05.07
		Structured light three-dimensional (3D) measurement system has been widely used and studied in optical metrology recent years. 3D surface construction methods with fringe projection techniques have become one of the most active research areas. The measurement principle, working process, system configurations, phase shifting fringes, phase error correction, phase unwrapping, high dynamic range measurement method are detailed. The advantages and disadvantages of the techniques are also discussed. The working flow, realization method, key techniques and existing problems of a phase shifting fringe projection system are introduced comprehensively, and the subsequent research directions are pointed out for the 3D shape measurement technology to meet the requirements of higher precision in advanced manufacturing in the further.
		2018 Vol. 39 (5): 628-640 [Abstract] ( 556 ) HTML (1 KB) PDF (2703 KB) ( 2254 )

	641	Optical System Design of High Precision Dynamic Star Simulator
		ZHAO Zi-chao,CHEN Qi-meng,TANG Zi-bo,WANG Zhe
		DOI: 10.3969/j.issn.1000-1158.2018.05.08
		In order to complete the calibration work of the star sensor and meet the technology requirement of large field, high accuracy for dynamic star simulator, the ZEMAX software is used to complete the design of the optical system according to the dynamic star simulator working principle, which can accurately simulate the star point. The experimental results show that the focal length of the system is 110 mm, the field of view is 16°, the distortion is less than 0.05%, the wave range is 0.5～0.8 μm and the MTF is higher than 0.7 at the frequency of 60 lp/mm. The method to determine the actual focal plane of the system after assembly is put forward, and then the precision of the optical system are analyzed. The results show that the imaging accuracy design of high-precision dynamic star simulator optical system can reach 9″, and the error between stars is less than 13″. So the whole system can meet the using need of the high-precision dynamic star simulator.
		2018 Vol. 39 (5): 641-644 [Abstract] ( 400 ) HTML (1 KB) PDF (1214 KB) ( 552 )

	645	The Development of the Flow Liquid Heat Capacity Experiment System
		ZHENG Yu-xin,WEI Zhao-hui,LI Jie
		DOI: 10.3969/j.issn.1000-1158.2018.05.09
		The flow liquid heat capacity experiment system was developed to measure heat capacity in the high temperature and high pressure range. The experiment system contained flow calorimeter, the electric heating system, the inside and outside two adiabatic shields. The temperature range of the apparatus was from 293 K to 453 K, and the pressure range was 0.1~20 MPa. Firstly, the pure water was adopted to calibrate coefficient of heat leakage, then, the toluene and cyclohexane were used to test the accuracy and reliability of the system at different temperatures and pressures. Through the uncertainty analysis, the expanded uncertainty of the experimental apparatus was less than 1.41%( k=2).
		2018 Vol. 39 (5): 645-650 [Abstract] ( 404 ) HTML (1 KB) PDF (1488 KB) ( 388 )

	651	Fault Diagnosis of Secondary Air Temperature of Grate Cooler Cement Clinker Heat Transfer Based on Improved Genetic Hill Climbing Algorithm
		LIU Bin,LIU Yong-ji,LIU Hao-ran,LI Lei,SUN Mei-ting
		DOI: 10.3969/j.issn.1000-1158.2018.05.10
		An improved combined algorithm(improved genetic hill climbing,IGHC) which utilizes the improved genetic operators to optimize Hill-Climbing is proposed.The algorithm adjusts the probability of crossover and mutation self adaptive, selects the way of crossover and mutation automatically, utilizes the crossover and mutation operators replace the edge deletion operator of HC to extend its ability of global optimization, and utilizes the Most Weight Supported Tree restrict the search space to improve search efficiency. Compared with HC and GA(genetic algorithm), the simulation results have shown that the IGHC algorithm can obtain a model more accurate and rapid, the best score of model is higher than GA and HC. Combined with cement grate cooler operating data in the process of cement clinker heat transfer, the fault diagnosis model of technological parameter can be constructed and a precise fault diagnosis of secondary air temperature in the cement grate cooler can be realized, so this algorithm has a certain practical significance.
		2018 Vol. 39 (5): 651-658 [Abstract] ( 371 ) HTML (1 KB) PDF (1773 KB) ( 454 )

	659	Temperature Calibration System for PCR Instrument
		YU Song-lin,WANG Zhe,SHEN Wen-jie,ZHANG Tao,JIANG Jing,TIAN Yun
		DOI: 10.3969/j.issn.1000-1158.2018.05.11
		In order to calibrate the temperature of PCR instrument, a method was introduced for thermistor encapsulation, and a temperature calibration system for PCR instrument based on multi-thermistor sensors was developed, also the verification experiment for the system was accomplished. The experimental results demonstrated that the uniformity and the absolute value of indication error of the calibration system developed was below 0.15℃ and 0.06℃ respectively. While the extended uncertainty for indication error was less than 0.07℃ (k=2). In addition, a PCR instrument was calibrated using the developed system, and the parameters, such as indication error, uniformity, heat rate and cool rate, were all obtained.
		2018 Vol. 39 (5): 659-662 [Abstract] ( 389 ) HTML (1 KB) PDF (706 KB) ( 265 )

	663	Numerical Simulation of Gas-liquid Two-phase Flow in Coriolis Flowmeter
		MA Ya-peng,SHI Chu,LUO Yu,SUGI Tokio,PANG Qiang,AKIZAKI Tsubasa
		DOI: 10.3969/j.issn.1000-1158.2018.05.12
		In the measurement of gas-liquid two-phase fluid, the Coriolismass flowmeter (CMF) measurement stability of the flow meter gradually deteriorated with the gas content increases. A method based on the fluid-solid coupling finite element technique has been developed for the modal analysis and fluid-solid coupling vibration analysis of the gas-fluid two-phase flow in Coriolis flowmeter. As an example, this method is used to simulate the effect of bubble content and distribution on measurement stability. The variation law of measurement stability has been preliminary mastered, that the measurement is relatively stable with a bubble content of 1%, and over 5% the stability changes rapidly.
		2018 Vol. 39 (5): 663-667 [Abstract] ( 425 ) HTML (1 KB) PDF (962 KB) ( 466 )

	668	Extraction Algorithm of Air Regulation Damper Discharge Characteristics in Boiler Based on Operational Data
		LIU Fu-guo,ZHANG Xu-hui
		DOI: 10.3969/j.issn.1000-1158.2018.05.13
		Measurement model of air flow rate in burner vents are presented, according to conventional configuration of measuring instruments in thermal power plant. Resistance characteristics of air regulation dampers are automatically extracted from running data by mechanism modeling and data mining technology, and costs of laboratory calibration tests are saved. The discharge flow characteristics of air regulation dampers are measured in a practical boiler by experiments, and compared with curves extracted from the running data, they match very well. Air flow rate measurements in burner vents makes it possible to monitor air and fuel distribution in furnace, it facilitates burner control and optimization in low NOx pulverized-coal-fired boiler.
		2018 Vol. 39 (5): 668-674 [Abstract] ( 375 ) HTML (1 KB) PDF (464 KB) ( 308 )

	675	Research on Hybrid Normalization Model of Electrical Capacitance Tomography
		ZHANG Li-feng,ZHU Feng
		DOI: 10.3969/j.issn.1000-1158.2018.05.14
		During the process of image reconstruction for electrical capacitance tomography technology, a hybrid normalization model of capacitance measurements is presented to obtain better describe of the permittivity distribution of the two-phase or multiphase media. The weight factor used in the presented hybrid normalization model is calculated based on the ratio of the minimum distance to the maximum distance between the subdivision element and electric field center line. And then, the corresponding sensitivity matrix is computed. Simulation and static test are carried out and the results show that both the accuracy and the shape fidelity can be improved obviously.
		2018 Vol. 39 (5): 675-678 [Abstract] ( 388 ) HTML (1 KB) PDF (923 KB) ( 226 )

	679	Improved Tikhonov Regularization Method for Image Reconstruction
		WEN Li-mei,ZHOU Miao-miao,LI Ming,MA Min
		DOI: 10.3969/j.issn.1000-1158.2018.05.15
		Tikhonov regularization method can resolve the ill-posedness of the inverse problem and balance the stability and accuracy of the solution in electrical capacitance tomography image reconstruction. However, its effectiveness can be seriously affected by the gross error of measurement data. Improved Tikhonov regularization method combines 2-norm and robust estimation, substitute a slower-growing Cauchy function for the quadratic sum in the least square method to further improve the robustness and adaptability of least square estimation. The effectiveness of the developed method is verified by COMSOL and MATLAB software. Reconstruction results demonstrate that the improved Tikhonov regularization method can effectively reduce influence of the gross error and improve image reconstruction accuracy and spatial resolution.
		2018 Vol. 39 (5): 679-683 [Abstract] ( 451 ) HTML (1 KB) PDF (1044 KB) ( 532 )

	684	Design of Angular Accelerometer Based on Resonant Optical Tunneling Effect
		LI Hui-ming,ZOU Lu,JIAN Ao-qun,WANG Lei-yang,DUAN Qian-qian,SANG Sheng-bo
		DOI: 10.3969/j.issn.1000-1158.2018.05.16
		Resonant optical tunneling effect (ROTE) is used to describe a design method of angular acceleration sensor and its sensing characteristics are analyzed. Finally, through theoretical analysis and simulation calculation using Mathematica based on the resonant optical tunneling effect,the quality factor and sensitivityof the accelerometer reach up to 1.96×108 and 0.1 °/nm, respectively, which is higher than that of the classic F-P cavity.
		2018 Vol. 39 (5): 684-687 [Abstract] ( 380 ) HTML (1 KB) PDF (525 KB) ( 230 )

	688	Rolling Bearing Fault Diagnosis Based on FDM and Singular Value Difference Spectrum
		FU Xiu-wei,GAO Xing-quan
		DOI: 10.3969/j.issn.1000-1158.2018.05.17
		Based on the characteristic that is the feature extraction of rolling bearing’s impact features is very hard under strong noise, a method based on Fourier decomposition method (FDM) and singular value difference spectrum is proposed. First, the non-stationary original bearing fault vibration signal was decomposed into several Fourier intrinsic band functions (FIBFs) by FDM. Then, the original signal was reconstructed by using correlation cross-coefficient method. The reconstructed signal was de-noised by the singular value difference spectrum. Finally, the fault characteristic frequency is accurately identified by using Hilbert envelope spectrum to the combined de-noised signal. The simulation analysis and test are good to verify the proposed method.
		2018 Vol. 39 (5): 688-692 [Abstract] ( 382 ) HTML (1 KB) PDF (1623 KB) ( 400 )

	693	Research on Correction Measuring Method of CG and Inertia Moment of Commercial Vehicle Cab
		WU Jun-gang,DING Fei,ZHOU Jian-wen,HAN Guo-yi
		DOI: 10.3969/j.issn.1000-1158.2018.05.18
		Based on the functions of CG (centre of gravity) position and inertia moment measurement of passenger vehicle dual-shaft K&C bench and existing separation measure method which are calculated by lever principle and moments of inertia parallel theorem, a correction method of CG position and inertia moment of commercial vehicle cab is developed. This correction method can consider K&C coordinate system changing to vehicle coordinate system and correcting the malposition between the installation position and design position. This method can solve problems shortage of existing separation measure method and correction method and its result is much better to more meet the engineering needs of commercial vehicle cab vibration isolation analysis, was verified through the test of known CG and inertia value calibration block.
		2018 Vol. 39 (5): 693-697 [Abstract] ( 361 ) HTML (1 KB) PDF (469 KB) ( 223 )

	698	Study on Torque Ripple Suppression Method for Single-phase Series Motor
		ZHAO Hao,FENG Hao
		DOI: 10.3969/j.issn.1000-1158.2018.05.19
		There are torque ripples for single-phase series motor when in working,which leads to the obvious vibration and noise.Therefore,a torque ripple suppression method for single-phase series motor is presented,which based on superposition offset of vibration wave.Namely adding another vibration wave,compared with original torque fluctuation,which is the same amplitude and stagger 180°phase.By analysing the work mechanism of motor,the torque ripple suppression method implementation conditions is received.Finally,torque ripples of single-phase series motor motor are tested,which the vibration wave is superimposed,the experiment results show that the torque ripple can be eliminated effectively,the feasibility of torque ripple suppression method is verified.
		2018 Vol. 39 (5): 698-701 [Abstract] ( 404 ) HTML (1 KB) PDF (432 KB) ( 240 )

	702	Study on the Time-dependent Change of Attenuation Coefficient of Ultrasound Contrast Agent
		LAN Qing,WANG Yue-bing,CAO Yong-gang,CHEN Qian
		DOI: 10.3969/j.issn.1000-1158.2018.05.20
		To study the influence of microbubble type ultrasound contrast agent (UCA) on the attenuation of acoustic propagation, based on the theoretical model of bubble dynamics to calculate the attenuation of acoustic propagation due to changes in microscopic particle size, and the analytical expression of the attenuation coefficient of the UCA with time variation was deduced. Moreover, an experimental system was built to measure the attenuation coefficient of the UCA. Experimental results verified the validity of the theoretical model and the exponential decay law of the attenuation coefficient of the UCA over time. This study provides a basis for reducing the propagation attenuation and distortion of ultrasound waves, making the UCA are effectively used in the field of ultrasound medicine.
		2018 Vol. 39 (5): 702-707 [Abstract] ( 381 ) HTML (1 KB) PDF (1264 KB) ( 583 )

	708	The Wireless Measurement System Utilizing Double Local-oscillator Excitation for Surface Acoustic Wave Resonators
		CHEN Zhao-xing,CHEN Zhi-jun,LI Qing-liang,Chen Tao,ZHAO Wen-yu
		DOI: 10.3969/j.issn.1000-1158.2018.05.21
		In the practical application of the surface acoustic wave (SAW) wireless sensing, concerning to the two SAW resonators as differential-type structure, one type of reader utilizing double local-oscillator excitation is designed.The reader could create an excitation signal including two carrier frequencies, so the two SAW resonators could response simultaneously.The wireless measurement system is established, and the transmit and receive chains are tested accordingly.The measurement results of the resonant frequencies displayed on the upper monitor show the reliability of the system.Furthermore, the measurement results of the differential frequencies and the longest distances under different excitation signals with different carrier frequencies are analyzed.
		2018 Vol. 39 (5): 708-711 [Abstract] ( 316 ) HTML (1 KB) PDF (967 KB) ( 317 )

	712	Ultrasonic Image Segmentation Based on Variance and Saliency Features
		QIU Dong-yue,JI Zhe,ZHU Teng-fei,MI Shang-yan,ZHU Hai-jiang
		DOI: doi: 10.3969/j.issn.1000-1158.2018.05.22
		According to the low contrast of ultrasound images can result the difference of adjacent grayscales is very small, and the human eyes are difficult to distinguish, an ultrasound image segmentation method based on variance and saliency features is proposed. Firstly, the variance and saliency features of the known sample pixels in the image are extracted, then the sample training is performed based on the variance and saliency features of the extracted sample pixel points using a support vector machine to obtain the classification model, finally, the training model is applied to the entire image to achieve effective segmentation of the image. Experimental results show that the proposed method is feasible and effective for the segmentation of ultrasound images.
		2018 Vol. 39 (5): 712-715 [Abstract] ( 273 ) HTML (1 KB) PDF (1111 KB) ( 228 )

	716	Application of Multi-line Function Method in Curve Fitting
		LI Xin-ying,LIU Kai,HUANG Hai-yan
		DOI: 10.3969/j.issn.1000-1158.2018.05.23
		In order to study the development trend of some phenomena, all kinds of curve fitting methods are needed, such as the polynomial trend model, the logarithm trend model, and so on. Based on the principle of multi surface function method, presents a multi linear function method, which is applied to the curve fitting. In order to verify the feasibility of the method, in the MATLAB platform development program on a railway line was calculated with polynomial fitting method under different conditions of experiment, proved the multivline function method has high accuracy, simple calculation and other advantages, is an excellent method of curve fitting.
		2018 Vol. 39 (5): 716-719 [Abstract] ( 318 ) HTML (1 KB) PDF (1305 KB) ( 586 )

	720	A New Online Fault Detection Method for Broken Rotor Bars in Induction Motor Considering Effects of Load Mutation
		JIANG Guo-qian,REN Xiao-ru,HE Qun,XIE Ping,DU Shuo,REN Zong-hao
		DOI: 10.3969/j.issn.1000-1158.2018.05.24
		When the broken rotor bar fault occurs in induction motors, the induced fault characteristic frequency components are easily masked by the fundamental frequency, and even worse, the interference caused by motor load mutation greatly increases the difficulty in extracting and detecting the fault characteristic frequency. In order to solve the issue, the analytic wavelet analysis and the stator current spectral subtraction method are combined to propose a new effective fault detection method. Firstly, the analytic wavelet is employed to determine the location and the load mutation and then the spectral subtraction operation is performed to eliminate current fundamental component and highlight fault characteristic frequencies. Furthermore, two indicators are defined to quantify fault levels of broken rotor bars. Simulation and experimental results show that the proposed method is more sensitive to fault characteristic frequency in the case of load mutation, meanwhile, describes the rotor fault severity quantitatively.
		2018 Vol. 39 (5): 720-724 [Abstract] ( 374 ) HTML (1 KB) PDF (1460 KB) ( 219 )

	725	A Method for Calculating the Dislocation Contrast Factor in X-ray Diffraction Profile Analysis
		HU Qiu-shi,ZHAO Feng,FU Hua
		DOI: 10.3969/j.issn.1000-1158.2018.05.25
		The displacement field produced by dislocations was calculated by using Teodosiu anisotropic elastic theory.The formulas for calculating the dislocation contrast factors of different slip systems were established.Taking the cubic crystal as example, the calculation process was simplified, and the contrast factors of dislocations distributed in 12 slip systems under 8 diffraction indices in f.c.c Cu and b.c.c Fe were given.The calculation results were compared with those in the literature.X-ray diffraction experiments were carried out on oxygen free copper subjected to different quasi-static compression loading strains.The role of the contrast factor in eliminating the anisotropy broadening of the diffraction profiles was described.The subgrain size, screw dislocation ratio and the dislocation density in the sample were obtained by using line profile analysis.
		2018 Vol. 39 (5): 725-730 [Abstract] ( 507 ) HTML (1 KB) PDF (635 KB) ( 452 )

	731	Basic Performance Analysis on Graphite Calorimeter for Primary Standard of Absorbed Dose
		WANG Pei-wei
		DOI: 10.3969/j.issn.1000-1158.2018.05.26
		As the standard of the absorbed dose, graphite calorimeter demands high recurrence rate. Analysis shows the performance of the graphite calorimeter system of NIM, the measurement of electric energy (power), the conversion relation between electric energy and radiation energy, and the measurement of the value of the absorbed dose reproduction. Related technical index was explained, meanwhile, it's stability was given. In order to test the measurement of the standard, specific heat capacity was measured. The measurement results was complared with BIMP's results, deviation is less than 0.1%.
		2018 Vol. 39 (5): 731-735 [Abstract] ( 382 ) HTML (1 KB) PDF (1369 KB) ( 227 )

	736	Purity Analysis of Some Terpenes by Peak Area Normalization Method
		MA Hao-miao,WU Hai,WANG De-fa,ZHANG Pei-zhuang,WANG Zhen
		DOI: 10.3969/j.issn.1000-1158.2018.05.27
		8 pure terpene reagents including limonene were analyzed by using both GC-MS and GC-FID. Here GC-MS was used to identify the impurities in terpene reagent, and GC-FID peak areas were normalized to obtain the purity data of specific terpene reagent. The uncertainty contributions from analytical repeatability, instrumental linearity, FID response factor (effective carbon number(ECN)), and those unknown trace components were evaluated.The measured purity were obtained as following: limonene(98.91%±0.71%), isoprene(99.09%±0.56%), α-pinene(98.91%±0.56%), β-pinene(98.81%±0.48%), α-terpinene(89.26%±0.99%), γ-terpinene(96.65%±0.82%), 2-carene(96.26%±0.76%), myrcene(91.29%±0.84%).
		2018 Vol. 39 (5): 736-740 [Abstract] ( 393 ) HTML (1 KB) PDF (599 KB) ( 375 )

	741	Optimization for NOx Prediction Model from Boilers Based on GSA-PELM
		NIU Pei-feng,SHI Chun-jian,LIU Nan,CHANG Ling-fang,ZHANG Xian-chen
		DOI: 10.3969/j.issn.1000-1158.2018.05.28
		As to precisely predict the NOx emission from boiler,an integrated modeling method was establisbcd based on gravitation search algorithm (GSA) and parallel extreme learning machine (PELM),and used the model to forecast the power plant boiler NOx emission concentration.As the generalization ability and accuracy of PELM rely on the choice of weight,using the gravitation search algorithm optimization PELM weights.Test sample data were collected in a coal-fired power plant 300 MW circulating fluidized bed boiler under different conditions,the simulation consequences showed that compared with PELM model,ELM model,GSA-LSSVM and GSA-ELM model,GSA-PELM model the accuracy could be improved by more than 9 orders of magnitude and can be used more effectively and accurately to predict NOx emission concentration of boilers in thermal power plants.
		2018 Vol. 39 (5): 741-746 [Abstract] ( 358 ) HTML (1 KB) PDF (1362 KB) ( 301 )

	747	Study on Fluorescence Spectrometric Detection of Potassium Sorbate Based on CS-SVM
		WANG Shu-tao,ZHU Cai-yun,LIU Ming-xin, PENG Tao,CHENG Qi,KONG De-ming,WANG Yu-tian
		DOI: 10.3969/j.issn.1000-1158.2018.05.29
		By analyzing the fluorescence spectra of potassium sorbate in orange juice solution, it is found that fluorescence spectrum of potassium sorbate has glares where emission wavelength is in the range of 450～510nm when excitation wavelength is at 375nm, which indicates that the fluorescence characteristics of orange juice could interfere with the fluorescence spectrum of potassium sorbate. The model of cuckoo search algorithm (CS) optimizing support vector machine (SVM) is built to train 15 samples and predict the concentration of 7 potassium sorbate samples. The average recovery rate of CS-SVM is 99.07% and the mean square error is 1.21×10^-5g/L. The results show that the training process,the average recovery and error of CS-SVM are all better than PSO-SVM and GA-SVM, and that CS-SVM can accurately determine the concentration of potassium sorbate in orange juice solution.
		2018 Vol. 39 (5): 747-752 [Abstract] ( 355 ) HTML (1 KB) PDF (3177 KB) ( 280 )

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