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A Method of Minimum Reusability Estimation for Automated Software Testing

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Journal of Shanghai Jiaotong university(Science) 2013年第3期18卷 360-365页

作者： KAN hong-xing WANG guo-qiang WANG Zong-dian DING Shuai School of Medical Information Technology Anhui University of Traditional Chinese Medicine Hefei 230038 China School of Management Hefei University of Technology Hefei 230009 China

Through reusing software test components, automated software testing generally costs less than manual software testing. There has been much research on how to develop the reusable test components, but few fall on how to estimate the reusability of test conlponents for automated testing. The purpose of this paper is to present a method of minimum reusability estimation for automated testing based on the return on investment （ROI） model. Minimum reusability is a benchmark for the whole automated testing process. If the reusability in one test execution is less than the minimum reusability, some new strategies must be adopted ill the next test execution to increase the reusability. Only by this way, we can reduce unnecessary costs and finally get a return on the investment of automated testing.

关键词： automated software testing manual software testing mean maintenance costs multiplier reusable software test components threshold minimum reusability estimation

New Mathematical Method for the Determination of Cutter Runout Parameters in Flat-end Milling

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 947-952页

作者： guo qiang SUN Yuwen guo Dongming ZHANG Chuantai Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

The cutting force prediction is essential to optimize the process parameters of machining such as feed rate optimization, etc. Due to the significant influences of the runout effect on cutting force variation in milling process, it is necessary to incorporate the cutter runout parameters into the prediction model of cutting forces. However, the determination of cutter runout parameters is still a challenge task until now. In this paper, cutting process geometry models, such as uncut chip thickness and pitch angle, are established based on the true trajectory of the cutting edge considering the cutter runout effect. A new algorithm is then presented to compute the cutter runout parameters for flat-end mill utilizing the sampled data of cutting forces and derived process geometry parameters. Further, three-axis and five-axis milling experiments were conducted on a machining centre, and resulting cutting forces were sampled by a three-component dynamometer. After computing the corresponding cutter runout parameters, cutter forces are simulated embracing the cutter runout parameters obtained from the proposed algorithm. The predicted cutting forces show good agreements with the sampled data both in magnitude and shape, which validates the feasibility and effectivity of the proposed new algorithm of determining cutter runout parameters and the new way to accurately predict cutting forces. The proposed method for computing the cutter runout parameters provides the significant references for the cutting force prediction in the cutting process.

关键词： flat end milling cutter runout cutting force five-axis machining

Redesigned Surface Based Machining Strategy and Method in Peripheral Milling of Thin-walled Parts

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Chinese Journal of Mechanical Engineering 2010年第3期23卷 282-287页

作者： JIA Zhenyuan guo qiang SUN Yuwen guo Dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

Currently, simultaneously ensuring the machining accuracy and efficiency of thin-walled structures especially high performance parts still remains a challenge. Existing compensating methods are mainly focusing on 3-aixs machining, which sometimes only take one given point as the compensative point at each given cutter location. This paper presents a redesigned surface based machining strategy for peripheral milling of thin-walled parts. Based on an improved cutting force/heat model and finite element method（FEM） simulation environment, a deflection error prediction model, which takes sequence of cutter contact lines as compensation targets, is established. And an iterative algorithm is presented to determine feasible cutter axis positions. The final redesigned surface is subsequently generated by skinning all discrete cutter axis vectors after compensating by using the proposed algorithm. The proposed machining strategy incorporates the thermo-mechanical coupled effect in deflection prediction, and is also validated with flank milling experiment by using five-axis machine tool. At the same time, the deformation error is detected by using three-coordinate measuring machine. Error prediction values and experimental results indicate that they have a good consistency and the proposed approach is able to significantly reduce the dimension error under the same machining conditions compared with conventional methods. The proposed machining strategy has potential in high-efficiency precision machining of thin-walled parts.

关键词： redesigned surface tool path part deflection error prediction finite element method

Design of infrared camouflage cloak for underground silos

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Defence Technology（防务技术） 2020年第1期16卷 43-49页

作者： Luo Zhang qiang Zhang hong Ye Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230027PR China

The temperature difference between the exposed surface of an underground silo and the surrounding soil surface is significant,which means a silo can be easily found by infrared *** designed an infrared camouflage cloak consisting of an imitative layer and an insulation layer for the *** imitative layer is used to imitate the thermal response of the soil to the surrounding *** insulation layer is used to weaken the impact of the internal temperature field of the silo on the lower boundary of the imitative layer.A silo model including surrounding soil and a soil model without silo were established,and the influences of the material and thickness of each layer on the infrared camouflage effect were *** results show that when using a silicone rubber containing alumina powder with a volume fraction of 3.18% as the imitative material,its thermal inertia is in consistent with that of the ***,it was found that the thickness of the imitative layer doesn't need to be greater than its thermal penetration depth to achieve the infrared camouflage,and the absence of the insulation layer will cause hot spots on the silo surface in winter to weaken the camouflage *** optimized thicknesses of the imitative layer and the insulation layer are 22 cm and 4 cm re *** simulations indicate that with the application of the cloak,the maximum value of the absolute values of the temperature differences between the average temperatures of the silo surface and the surrounding soil surface temperatures drops from 1,59℃ to 0.31℃ in summer and from 1.92℃ to 0.21℃ in *** designed cloak can achieve an all-weather and full-time passive infrared camouflage.

关键词： Underground silo Infrared camouflage cloak Imitative layer Insulation layer

Research on SFLA-Based Bidirectional Coordinated Control Strategy for EV Battery Swapping Station

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Computers, Materials & Continua 2017年第4期53卷 343-356页

作者： guo Zhao Jiang guo Hao qiang Key Laboratory of Hydraulic Machinery Transients(Wuhan University) Ministry of EducationyWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China School of Urban Rail Transit Changzhou UniversityChangzhou 213164China

As a good measure to tackle the challenges from energy shortages and environmental pollution,Electric Vehicles(EVs)have entered a period of rapid *** swapping station is a very important way of energy supply to EVs,and it is urgently needed to explore a coordinated control strategy to effectively smooth the load fluctuation in order to adopt the large-scale *** bidirectional power flow between the station and power grid,this paper proposed a SFLA-based control strategy to smooth the load ***,compared simulations were performed according to the related *** to particle swarm optimization(PSO)method,the presented SFLA-based strategy can effectively lower the peak-valley difference with the faster convergence rate and higher convergence *** is important for the swapping station that energy exchanging mode can supply energy for large-scale EVs with a smoother load profile than one-way charging mode.

关键词： SFLA bidirectional coordinated control battery swapping station optimization

Magnetoacoustic position imaging for liquid metal in animal interstitial structure

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Chinese Physics B 2020年第5期29卷 346-353页

作者： Xiao-He Zhao guo-qiang Liu Hui Xia Yan-hong Li Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Magnetoacoustic tomography with magnetic induction(MAT-MI),as a new kind of in-vivo imaging method,has potential application value in interstitial fluid *** this paper,we propose the application of MAT-MI with liquid metal serving as a tracer of the interstitial structure to study its fluid behavior,and use it to implement the positional imaging of the spatial distribution of liquid *** to the particularity of liquid metal magnetoacoustic pressure(MAP)signals,we propose an envelope analysis method to extract the rising edge of the amplitude envelope of the detected waveform as effective position *** for the first time,we propose the method of superpositing pixel matrix to achieve the position imaging of liquid ***,the positional imaging of the liquid metal sample embedded in the gel is achieved to have relatively accurate *** study provides a method of effectively extracting data and implementing the position imaging for liquid metal in the interstitial structure in the frame of MAT-MI.

关键词： magnetic acoustic tomography with magnetic induction(MAT-MI) liquid metal interstitial structure position imaging

Analytical modeling of geometric errors induced by cutter runout and tool path optimization for five-axis flank machining

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Science China(Technological Sciences) 2011年第12期54卷 3180-3190页

作者： guo qiang SUN YuWen guo DongMing Key Laboratory for Precision and Non-Traditional Machining Technology of the Ministry of Education Dalian University of Technology Dalian 116024 China

The cutter runout effect has significant influence on the shape of cutter swept surface and the machining surface quality. Hence,it is necessary to integrate the cutter runout effect in cutter swept surface modeling,geometric error prediction and tool path optimization for five-axis flank machining. In this paper,an envelope surface model considering cutter runout effect is first established,and geometric errors induced by runout effect are derived based on the relative motion analysis between the cutter and part in machining. In the model,the cutter runout is defined by four parameters,including inclination angle,location angle,offset value and the length of cutter axis. Then the runout parameters are integrated into the rotation surface of each cutting edge that is used to form the final cutter envelope surface for the five-axis machining process. Thus,the final resulting geometric errors of the machined surface induced by cutter runout can be obtained through computing the deviations from the nominal cutter swept surface. To reduce these errors,an iterative least square method is used to optimize the tool paths for five-axis flank machining. Finally,a validation example is given for a specific ruled surface. Results show the effectiveness and feasibility of the analytical model of geometric errors induced by cutter runout,and also show that the geometric errors can be reduced significantly using the proposed tool path planning method.

关键词： cutter runout tool path optimization envelope surface five-axis machining geometric errors

High-performance Cu_(0.95)V_(2)O_(5) nanoflowers as cathode materials for aqueous zinc-ion batteries

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Rare Metals 2022年第1期41卷 29-36页

作者： Xin Yu Fang Hu Zhi-qiang guo Lei Liu Gui-hong Song Kai Zhu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Weifang City Planning&Design Institute Weifang 261000China Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150010China

Exploring high-performance cathode materials for aqueous zinc ion batteries(ZIBs)is still one of the critical *** vanadate compound has become a potential cathode material for ZIBs with a novel displacement reaction mechanism of reversible reduction/oxidation of Cu^(2+)/Cu^(0).Herein,we reported Cu_(0.95)V_(2)O_(5)nanoflowers prepared using a hydrothermal synthesis method as a capable cathode material for *** Cu_(0.95)V_(2)O_(5)nanoflowers exhibit high specific capacity of 405 mAh·g^(-1) at the current density of 100 mA·g^(-1),benefiting from the displacement reaction mechanism and phase transformation mechanism from Cu_(0.95)V_(2)O_(5)to the open and stable architecture Cu_(0.4)V_(2)O_(5)and Zn3(OH)2V2O7·2H2O *** cathode exhibits excellent rate performance with a high capacity of-200 mAh·g^(-1)at 5 A·g^(-1) and outstanding cycle stability with a capacity retention of 92%after 1000 *** is anticipated that the novel Cu_(0.95)V_(2)O_(5)nanoflowers are promising cathode material in the application for zinc ion batteries.

关键词： flowers performance cathode

Mechanical properties of thermal aged HTPB composite solid propellant under confining pressure

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Defence Technology（防务技术） 2022年第4期18卷 618-625页

作者： Zhe-jun Wang hong-fu qiang 206 Staff Room Xi’an Hi-Tech InstituteXi'an710025PR China

With the purpose of investigating the effects of confining pressure and aging on the mechanical properties of Hydroxyl-terminated polybutadiene(HTPB)based composite solid propellant,tensile tests of thermal accelerated aged propellant samples under room temperature and different confining pressure conditions were performed through the use of a self-made confining pressure device and conventional testing ***,the maximum tensile stressσmand the corresponding strainεm for the propellant under different test conditions were obtained and *** results indicate that confining pressure and aging can significantly affect the mechanical properties of HTPB propellant,and the coupled effects are very *** the one hand,the stressσmincreases as a whole when confining pressure becomes higher or thermal aging time ***,this stress is more sensitive to aging with increasing confining *** are almost three regions in the stress increments(σm P-σm0)/σm0and thermal aging time curves for HTPB *** maximum value of the stress increment(σm P-σm0)/σm0for the propellant is about 98%at 7.0 MPa and 170 *** the other hand,the strainεm decreases with increasing thermal aging time under the whole confining pressure ***,the variation of this strain with confining pressure is more complex at various thermal aging time,which is different from that of unaged solid propellant in previous *** addition,this strain is slightly less sensitive to aging as the confining pressure ***,there is also a critical confining pressure in this investigation,whose value is between 0.15 MPa and 4.0 *** this critical pressure,the trends of the stressσmand the corresponding strainεm all ***,there are some critical thermal aging time for the stress increment(σm P-σm0)/σm0and strain increment(εm P-εm0)/εm0of HTPB propellant in this investigation,which are about at 35,50 and 170 ***,based on the tw

关键词： Thermal accelerated aging Confining pressure Hydroxyl-terminated polybutadiene propellant Mechanical properties Strength criterion