Pub Date : 2020-03-15DOI: 10.5545/sv-jme.2019.6461
K. Jiang, K. Gao, L. Wan
Coal consists of diverse materials, and gangue is one of the most common ones. At present, most mathematical models about cutting force and specific energy in the cutting process have not taken gangue minerals in coal seams into consideration. The gangue distribution function is proposed to simulate situations in which gangue minerals are in different distributions. Moreover, the cutting force due to gangue mineral at different heights is also obtained with the finite element method. Combined with the gangue distribution function, the increased cutting force due to gangue minerals can be obtained for any gangue distribution. The present paper also proposes a new mathematical model to calculate the increased specific energy under different gangue distributions. The results show that the gangue distribution function is useful for simulating various situations of gangue distributions in coal seams. Under dispersive gangue distribution in coal seams, the increased mean cutting force, as well as the increased specific energy, is less influenced by gangue distribution, and it tends to be a constant. These results can be useful for the related research on coal cutting under complicated conditions.
{"title":"Effect of Gangue Distributions on Cutting Force and Specific Energy in Coal Cutting","authors":"K. Jiang, K. Gao, L. Wan","doi":"10.5545/sv-jme.2019.6461","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6461","url":null,"abstract":"Coal consists of diverse materials, and gangue is one of the most common ones. At present, most mathematical models about cutting force and specific energy in the cutting process have not taken gangue minerals in coal seams into consideration. The gangue distribution function is proposed to simulate situations in which gangue minerals are in different distributions. Moreover, the cutting force due to gangue mineral at different heights is also obtained with the finite element method. Combined with the gangue distribution function, the increased cutting force due to gangue minerals can be obtained for any gangue distribution. The present paper also proposes a new mathematical model to calculate the increased specific energy under different gangue distributions. The results show that the gangue distribution function is useful for simulating various situations of gangue distributions in coal seams. Under dispersive gangue distribution in coal seams, the increased mean cutting force, as well as the increased specific energy, is less influenced by gangue distribution, and it tends to be a constant. These results can be useful for the related research on coal cutting under complicated conditions.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75742835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-15DOI: 10.5545/sv-jme.2019.6294
Tao Liu, Z. Deng, Lishu Lv, Shuailong She, Wei Liu, Cheng Luo
Experimental Analysis of Process Parameter Effects on Vibrations in the High-Speed Grinding of a Camshaft Liu, T. – Deng, Z. – Lv, L. – She, S. – Liu, W. – Luo, C. Tao Liu1,2 – Zhaohui Deng1,2,* – Lishu Lv1,2 – Shuailong She1,2 – Wei Liu1,2 – Chengyao Luo1,2 1 Hunan University of Science and Technology, Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult to Machine Material, China 2 Hunan University of Science and Technology, Intelligent Manufacturing Institute, China
{"title":"Experimental Analysis of Process Parameter Effects on Vibrations in the High-Speed Grinding of a Camshaft","authors":"Tao Liu, Z. Deng, Lishu Lv, Shuailong She, Wei Liu, Cheng Luo","doi":"10.5545/sv-jme.2019.6294","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6294","url":null,"abstract":"Experimental Analysis of Process Parameter Effects on Vibrations in the High-Speed Grinding of a Camshaft Liu, T. – Deng, Z. – Lv, L. – She, S. – Liu, W. – Luo, C. Tao Liu1,2 – Zhaohui Deng1,2,* – Lishu Lv1,2 – Shuailong She1,2 – Wei Liu1,2 – Chengyao Luo1,2 1 Hunan University of Science and Technology, Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult to Machine Material, China 2 Hunan University of Science and Technology, Intelligent Manufacturing Institute, China","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86887284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-15DOI: 10.5545/sv-jme.2019.6283
Heyong Si, Li-hua Cao, Litan Pan
In order to study the steam flow excited vibration caused by the eccentricity of a rotor, three-dimensional rotor whirl motion is simulated based on mesh deformation. The mechanism of steam flow excited vibration and its influence on the dynamic characteristics of the rotor are investigated. The results show that the exciting forces change with the displacement of the rotor’s centre. Rotor dynamic coefficients are nonlinear when the rotor whirls pass the mesh deformation. The rotor dynamic coefficients and effective damping increase with the increase of whirl frequency. When the whirl frequency is 24.41 Hz, the rotor dynamic coefficients are strongly affected by rotational velocity. The maximum fluctuations of average direct stiffness, cross-coupling stiffness, direct damping and cross-coupling damping are 8.1 %, 113.2 %, 45.8 %, and 121.0 %, respectively. Effective damping fluctuates greatly when both whirl and rotational frequency are 24.41 Hz. The direct stiffness, direct damping, and effective damping increase with the increase of pressure ratio, which can improve rotor stability. The pressure fluctuation on the rotor’s surface is a primary reason for steam flow excited vibration. The stability margin of the rotor can be estimated precisely via effective damping.
{"title":"Dynamic Characteristics and Stability Prediction of Steam Turbine Rotor Based on Mesh Deformation","authors":"Heyong Si, Li-hua Cao, Litan Pan","doi":"10.5545/sv-jme.2019.6283","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6283","url":null,"abstract":"In order to study the steam flow excited vibration caused by the eccentricity of a rotor, three-dimensional rotor whirl motion is simulated based on mesh deformation. The mechanism of steam flow excited vibration and its influence on the dynamic characteristics of the rotor are investigated. The results show that the exciting forces change with the displacement of the rotor’s centre. Rotor dynamic coefficients are nonlinear when the rotor whirls pass the mesh deformation. The rotor dynamic coefficients and effective damping increase with the increase of whirl frequency. When the whirl frequency is 24.41 Hz, the rotor dynamic coefficients are strongly affected by rotational velocity. The maximum fluctuations of average direct stiffness, cross-coupling stiffness, direct damping and cross-coupling damping are 8.1 %, 113.2 %, 45.8 %, and 121.0 %, respectively. Effective damping fluctuates greatly when both whirl and rotational frequency are 24.41 Hz. The direct stiffness, direct damping, and effective damping increase with the increase of pressure ratio, which can improve rotor stability. The pressure fluctuation on the rotor’s surface is a primary reason for steam flow excited vibration. The stability margin of the rotor can be estimated precisely via effective damping.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76687829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-15DOI: 10.5545/sv-jme.2019.6474
S. Sundriyal, Vipin, R. S. Walia
The Powder-Mixed Near-Dry Electric Discharge Machining (PMND-EDM) methodology has proven to be efficient in terms of machining rate, surface morphology, and environmental friendliness, unlike traditional EDM. In this study, the presence of a conductive metallic powder (zinc) in the dielectric medium was responsible for changing the topography of the workpiece (EN-31) and resulted in a higher micro-hardness value of the machined component. In this research, an approach has been made to optimize the significant process parameters by using a Taguchi L9 orthogonal array (OA) to obtain machined components with higher values of micro-hardness, which was measured in terms of Vickers hardness HV. The selected process parameters were tool diameter, mist flow rate, metallic powder concentration, and dielectric mist pressure. By introducing foreign particles (metallic powder), the topography of the machined products has been improved, and the micro-hardness value was found to be enhanced. The confirmation experiment was performed for optimal process parameter settings, and the enhanced microhardness value was found to be 506.63 HV in the machined EN-31 die steel.
{"title":"Experimental Investigation of the Micro-hardness of EN-31 Die Steel in a Powder-Mixed Near-Dry Electric Discharge Machining Method","authors":"S. Sundriyal, Vipin, R. S. Walia","doi":"10.5545/sv-jme.2019.6474","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6474","url":null,"abstract":"The Powder-Mixed Near-Dry Electric Discharge Machining (PMND-EDM) methodology has proven to be efficient in terms of machining rate, surface morphology, and environmental friendliness, unlike traditional EDM. In this study, the presence of a conductive metallic powder (zinc) in the dielectric medium was responsible for changing the topography of the workpiece (EN-31) and resulted in a higher micro-hardness value of the machined component. In this research, an approach has been made to optimize the significant process parameters by using a Taguchi L9 orthogonal array (OA) to obtain machined components with higher values of micro-hardness, which was measured in terms of Vickers hardness HV. The selected process parameters were tool diameter, mist flow rate, metallic powder concentration, and dielectric mist pressure. By introducing foreign particles (metallic powder), the topography of the machined products has been improved, and the micro-hardness value was found to be enhanced. The confirmation experiment was performed for optimal process parameter settings, and the enhanced microhardness value was found to be 506.63 HV in the machined EN-31 die steel.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87278193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-15DOI: 10.5545/sv-jme.2019.6302
Tao Zhang, Qiang Wang, Xiaohui He, Li Sisheng, X. Shen
Energy management strategy is a critical technology for improving the fuel economy of wheel-drive hydraulic hybrid vehicles. For driving, a power-following control strategy is proposed in this study by adding several working points of the engine in the optimal fuel economy power curve. For braking, the “I” curve distribution strategy based on critical braking strength zmin was adopted. A test bench was constructed according to the quarter of the prototype vehicle. Taking the typical working conditions of Federal Urban Driving Schedule (FUDS) and the selfset extra-urban driving schedule (EUDC-1) cycle condition into consideration, the energy management strategy was studied. The torque and speed of the simulated engine and pressure of the accumulator were obtained. The test fuel consumption in this research was compared with the original fuel consumption of the prototype vehicle. It was found that the proposed energy management strategy could effectively improve the fuel economy by more than 24 % under the requirement of satisfying the dynamic performance of the whole vehicle.
{"title":"Power-Following Control Strategy of a Wheel-Drive Hydraulic Hybrid Vehicle","authors":"Tao Zhang, Qiang Wang, Xiaohui He, Li Sisheng, X. Shen","doi":"10.5545/sv-jme.2019.6302","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6302","url":null,"abstract":"Energy management strategy is a critical technology for improving the fuel economy of wheel-drive hydraulic hybrid vehicles. For driving, a power-following control strategy is proposed in this study by adding several working points of the engine in the optimal fuel economy power curve. For braking, the “I” curve distribution strategy based on critical braking strength zmin was adopted. A test bench was constructed according to the quarter of the prototype vehicle. Taking the typical working conditions of Federal Urban Driving Schedule (FUDS) and the selfset extra-urban driving schedule (EUDC-1) cycle condition into consideration, the energy management strategy was studied. The torque and speed of the simulated engine and pressure of the accumulator were obtained. The test fuel consumption in this research was compared with the original fuel consumption of the prototype vehicle. It was found that the proposed energy management strategy could effectively improve the fuel economy by more than 24 % under the requirement of satisfying the dynamic performance of the whole vehicle.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75025277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-15DOI: 10.5545/sv-jme.2019.6267
Peilin Zhang, Bo Li, Xuewen Wang, Chaoyang Liu, Wenjie Bi, Haozhou Ma
*Corr. Author’s Address: Taiyuan University of Technology, College of Mechanical and Vehicle Engineering, Taiyuan, China, wxuew@163.com 114 The Loading Characteristics of Bulk Coal in the Middle Trough and Its Influence on Rigid Body Parts Zhang, P. – Li, B. – Wang, X. – Liu, C. – Bi, W. – Ma, H. Peilin Zhang1,2 – Bo Li1,2 – Xuewen Wang1,2,* – Chaoyang Liu1,2 – Wenjie Bi1,2 – Haozhou Ma1,2 1 Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, China 2 Taiyuan University of Technology, College of Mechanical and Vehicle Engineering, China
{"title":"The Loading Characteristics of Bulk Coal in the Middle Trough and Its Influence on Rigid Body Parts","authors":"Peilin Zhang, Bo Li, Xuewen Wang, Chaoyang Liu, Wenjie Bi, Haozhou Ma","doi":"10.5545/sv-jme.2019.6267","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6267","url":null,"abstract":"*Corr. Author’s Address: Taiyuan University of Technology, College of Mechanical and Vehicle Engineering, Taiyuan, China, wxuew@163.com 114 The Loading Characteristics of Bulk Coal in the Middle Trough and Its Influence on Rigid Body Parts Zhang, P. – Li, B. – Wang, X. – Liu, C. – Bi, W. – Ma, H. Peilin Zhang1,2 – Bo Li1,2 – Xuewen Wang1,2,* – Chaoyang Liu1,2 – Wenjie Bi1,2 – Haozhou Ma1,2 1 Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, China 2 Taiyuan University of Technology, College of Mechanical and Vehicle Engineering, China","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78432730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-15DOI: 10.5545/sv-jme.2019.6320
M. Mileșan, C. C. Gîrdu, L. Cîrțînă, C. Rădulescu
This study supports the research in the field of laser cutting of steel sheets HARDOX400 (H400), a less well-known and analysed material. An H400 sheet with a thickness of 10 mm was used; a cutting plan was prepared according to Taguchi’s method; the input parameters (laser power, assistant gas pressure and cutting speed) were varied according to a specific rule, producing nine pieces. The initial factorial experiment was replicated four times under the same conditions as the initial one. The values for the cutting width between the piece and the plate, the hardness, and the roughness of the 45 resulting pieces were measured. The results were interpreted for each measured parameter, and by using design of experiments (DOE) from the Statistics 7.0 software, we obtained the description of roughness (Ra) in terms of power and speed using Response Surface Method (RSM) for prediction and correlation formula.
{"title":"Mathematical Modelling Study of Hardox400 Steel Parts’ Roughness and Hardness, Cut with CO2 Laser","authors":"M. Mileșan, C. C. Gîrdu, L. Cîrțînă, C. Rădulescu","doi":"10.5545/sv-jme.2019.6320","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6320","url":null,"abstract":"This study supports the research in the field of laser cutting of steel sheets HARDOX400 (H400), a less well-known and analysed material. An H400 sheet with a thickness of 10 mm was used; a cutting plan was prepared according to Taguchi’s method; the input parameters (laser power, assistant gas pressure and cutting speed) were varied according to a specific rule, producing nine pieces. The initial factorial experiment was replicated four times under the same conditions as the initial one. The values for the cutting width between the piece and the plate, the hardness, and the roughness of the 45 resulting pieces were measured. The results were interpreted for each measured parameter, and by using design of experiments (DOE) from the Statistics 7.0 software, we obtained the description of roughness (Ra) in terms of power and speed using Response Surface Method (RSM) for prediction and correlation formula.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81190215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-15DOI: 10.5545/sv-jme.2019.6324
K. Urbanowicz, H. Duan, A. Bergant
Nowadays, plastic pipes play a key role in fluid conveyance, for example, in urban water supply systems. Dynamic analysis of designed water pipe networks requires the use of numerical methods that allow for solving basic equations that describe transient flows occurring in plastic pipes. In this paper, the main equations were formulated with pressure (p) and velocity (v) as the principal variables. A novel simplified retarded strain solution is used to properly model the pipe-wall viscoelasticity effect during transient flow process. Unsteady friction is calculated with the use of a filtered weighting function (with three exponential terms). The proposed numerical method enables the efficient modelling of transient flow in plastic pressurized pipes. Extensive simulations are performed and compared with experimental results known from three different European research centres (London, Cassino, and Lyon), with the aim of demonstrating the impacts of plastic pipe properties and frequency-dependent hydraulic resistance on transient pipe flow oscillations. The effectiveness of the proposed method for determining the creep functions of plastic pipes is also examined and discussed.
{"title":"Transient Liquid Flow in Plastic Pipes","authors":"K. Urbanowicz, H. Duan, A. Bergant","doi":"10.5545/sv-jme.2019.6324","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6324","url":null,"abstract":"Nowadays, plastic pipes play a key role in fluid conveyance, for example, in urban water supply systems. Dynamic analysis of designed water pipe networks requires the use of numerical methods that allow for solving basic equations that describe transient flows occurring in plastic pipes. In this paper, the main equations were formulated with pressure (p) and velocity (v) as the principal variables. A novel simplified retarded strain solution is used to properly model the pipe-wall viscoelasticity effect during transient flow process. Unsteady friction is calculated with the use of a filtered weighting function (with three exponential terms). The proposed numerical method enables the efficient modelling of transient flow in plastic pressurized pipes. Extensive simulations are performed and compared with experimental results known from three different European research centres (London, Cassino, and Lyon), with the aim of demonstrating the impacts of plastic pipe properties and frequency-dependent hydraulic resistance on transient pipe flow oscillations. The effectiveness of the proposed method for determining the creep functions of plastic pipes is also examined and discussed.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79877428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-15DOI: 10.5545/sv-jme.2019.6298
Guangjiang Wang, Li-ying Su, Shuaidong Zou
Uneven Load Contact Dynamic Modelling and Transmission Error Analysis of a 2K-V Reducer with Eccentricity Excitation Wang, G. – Su, L. – Zou, S. Guangjian Wang 1,2,* – Li Su1,3 – Shuaidong Zou1,3 1 Chongqing University, State Key Laboratory of Mechanical Transmissions, China 2 Chongqing University, School of Automotive Engineering, China 3 Chongqing University, College of Mechanical Engineering, China
{"title":"Uneven Load Contact Dynamic Modelling and Transmission Error Analysis of a 2K-V Reducer with Eccentricity Excitation","authors":"Guangjiang Wang, Li-ying Su, Shuaidong Zou","doi":"10.5545/sv-jme.2019.6298","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6298","url":null,"abstract":"Uneven Load Contact Dynamic Modelling and Transmission Error Analysis of a 2K-V Reducer with Eccentricity Excitation Wang, G. – Su, L. – Zou, S. Guangjian Wang 1,2,* – Li Su1,3 – Shuaidong Zou1,3 1 Chongqing University, State Key Laboratory of Mechanical Transmissions, China 2 Chongqing University, School of Automotive Engineering, China 3 Chongqing University, College of Mechanical Engineering, China","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2020-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89724561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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