Machine vision has been used in the industrial automation system for a long time. It also plays a significant role in the field of human behavior recognition. Behavior recognition based on machine vision, such as object tracking, motion detection and crime recognition, greatly broadens the application field of artificial intelligence and has a good application prospect. We summarize the latest applications of various machine learning algorithms in human behavior recognition, and analyze the accuracy of various algorithms combined with data sets, so as to provide reference for researchers in related fields. By sorting out the typical research results, briefly expound on the application of machine learning in the field of behavior recognition in recent years. This review focuses on the Two Stream Network structure, TSN structure, LSTM network and C3D network. This paper analyzes the principles, advantages and disadvantages of various human behavior recognition methods, and briefly discusses the future development direction. The wide application prospect of behavior recognition and detection makes it a hot research direction in the field of computer vision, and greatly improves the accuracy of complex human motion recognition combined with deep learning. However, it still faces many difficulties, such as insufficient discrimination of violence attributes, difficult collection, verification of special action data and insufficient hardware computing resources, etc.
{"title":"Research Progress on the Human Behavior Recognition Based on Machine Learning Methods","authors":"Peijian Zhou, Wen-Jay Yu, L. Shu, Shang Wei, Chenglong Jiang, Haisheng Zheng","doi":"10.2174/2212797615666220827164210","DOIUrl":"https://doi.org/10.2174/2212797615666220827164210","url":null,"abstract":"\u0000\u0000Machine vision has been used in the industrial automation system for a long time. It also plays a significant role in the field of human behavior recognition. Behavior recognition based on machine vision, such as object tracking, motion detection and crime recognition, greatly broadens the application field of artificial intelligence and has a good application prospect.\u0000\u0000\u0000\u0000We summarize the latest applications of various machine learning algorithms in human behavior recognition, and analyze the accuracy of various algorithms combined with data sets, so as to provide reference for researchers in related fields.\u0000\u0000\u0000\u0000By sorting out the typical research results, briefly expound on the application of machine learning in the field of behavior recognition in recent years. This review focuses on the Two Stream Network structure, TSN structure, LSTM network and C3D network.\u0000\u0000\u0000\u0000This paper analyzes the principles, advantages and disadvantages of various human behavior recognition methods, and briefly discusses the future development direction.\u0000\u0000\u0000\u0000The wide application prospect of behavior recognition and detection makes it a hot research direction in the field of computer vision, and greatly improves the accuracy of complex human motion recognition combined with deep learning. However, it still faces many difficulties, such as insufficient discrimination of violence attributes, difficult collection, verification of special action data and insufficient hardware computing resources, etc.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48520761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-26DOI: 10.2174/2212797615666220826121726
Xinyang Gu, Ben Zhang, Zhongru Tang, Meilin Wang, Yaquan Liang
In response to the current needs for the development of large-scale wheat combine harvesters, this paper carried out the structure design and performance test of a large feed volume wheeled wheat combine harvester. Based on the characteristics of wheat plants, this paper designed a wheeled wheat combine harvester with a feed rate of 10kg/s. Subsequently, the structural parameters and design process of the main working components such as the header feeding device, the conveying device, the threshing device, the separation and cleaning device, the walking device, the cab, and the straw crushing device are elaborated. The strength of the key parts was checked by finite element simulation, and the structural parameters were optimized. The results show that the large feed volume combine harvester which designed in this paper can achieve entrainment loss rate of less than 2.39% and cleaning loss rate of less than 0.26%, significantly lower than the current 3% loss rate and there is almost no unclean and broken situation. This research provides reference for the design of large feed volume combine harvester.
{"title":"Structure Design and Performance Test of Wheat Combine Harvester Based on Numerical Modeling","authors":"Xinyang Gu, Ben Zhang, Zhongru Tang, Meilin Wang, Yaquan Liang","doi":"10.2174/2212797615666220826121726","DOIUrl":"https://doi.org/10.2174/2212797615666220826121726","url":null,"abstract":"\u0000\u0000In response to the current needs for the development of large-scale wheat combine harvesters, this paper carried out the structure design and performance test of a large feed volume wheeled wheat combine harvester.\u0000\u0000\u0000\u0000Based on the characteristics of wheat plants, this paper designed a wheeled wheat combine harvester with a feed rate of 10kg/s. Subsequently, the structural parameters and design process of the main working components such as the header feeding device, the conveying device, the threshing device, the separation and cleaning device, the walking device, the cab, and the straw crushing device are elaborated. The strength of the key parts was checked by finite element simulation, and the structural parameters were optimized.\u0000\u0000\u0000\u0000The results show that the large feed volume combine harvester which designed in this paper can achieve entrainment loss rate of less than 2.39% and cleaning loss rate of less than 0.26%, significantly lower than the current 3% loss rate and there is almost no unclean and broken situation.\u0000\u0000\u0000\u0000This research provides reference for the design of large feed volume combine harvester.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42212172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-17DOI: 10.2174/2212797615666220817112105
Liang Tang, Yang Liu
In order to further study the characteristics of flow parameters in the wellbore during solid fluidization drilling, based on the physical model of solid fluidization exploration of hydrate reservoir, a gas-liquid-solid three-phase flow model is established during drilling process. The parameter changes of wellbore pressure, section gas holdup, liquid volume fraction, temperature and wellbore hydrate decomposition rate under the influence of different wellhead choke pressure, displacement and drilling fluid density during solid fluidization are analyzed. The analysis results of the case well show that under different wellhead choke pressures, hydrate begins to decompose at 400m to 500m, and with the increase of wellhead choke pressure, the wellbore pressure and the volume fraction of liquid and solid phase at the same position increase significantly, and the gas production rate and the gas volume fraction decrease. The results also show that under different drilling fluid rate, hydrate begins to decompose at 500m to 550m, and with the increase of drilling fluid rate, bottomhole pressure and wellbore temperature increase, the situation of hydrate decomposition becomes earlier, and gas volume fraction decreases. With the increase of drilling fluid density, hydrate begins to decompose at 500m to 600m, the wellbore temperature increases, and the hydrate decomposition is delayed. Meanwhile, the difference in the location of hydrate decomposition becomes smaller.
{"title":"Mathematical Model Research on the Influence of Fluid Parameter Characteristics on the Solid Fluidization Exploration Process of Hydrate Reservoir","authors":"Liang Tang, Yang Liu","doi":"10.2174/2212797615666220817112105","DOIUrl":"https://doi.org/10.2174/2212797615666220817112105","url":null,"abstract":"\u0000\u0000In order to further study the characteristics of flow parameters in the wellbore during solid fluidization drilling, based on the physical model of solid fluidization exploration of hydrate reservoir, a gas-liquid-solid three-phase flow model is established during drilling process.\u0000\u0000\u0000\u0000The parameter changes of wellbore pressure, section gas holdup, liquid volume fraction, temperature and wellbore hydrate decomposition rate under the influence of different wellhead choke pressure, displacement and drilling fluid density during solid fluidization are analyzed.\u0000\u0000\u0000\u0000The analysis results of the case well show that under different wellhead choke pressures, hydrate begins to decompose at 400m to 500m, and with the increase of wellhead choke pressure, the wellbore pressure and the volume fraction of liquid and solid phase at the same position increase significantly, and the gas production rate and the gas volume fraction decrease. The results also show that under different drilling fluid rate, hydrate begins to decompose at 500m to 550m, and with the increase of drilling fluid rate, bottomhole pressure and wellbore temperature increase, the situation of hydrate decomposition becomes earlier, and gas volume fraction decreases.\u0000\u0000\u0000\u0000With the increase of drilling fluid density, hydrate begins to decompose at 500m to 600m, the wellbore temperature increases, and the hydrate decomposition is delayed. Meanwhile, the difference in the location of hydrate decomposition becomes smaller.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44861242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-16DOI: 10.2174/2212797615666220816101151
Xin Zhang, Feitang Wang, Zhanlong Li, Jianwei Li
When driving and working, the engine, working equipment and uneven road sur-face will cause severe vibrations to the wheeled excavator, 1which can affect efficiency and comfort. This paper discusses various patents and presents a new method of vibration reduction for excavators. The purpose of the research is to design the counterweight of the excavator as tuned mass of tuned mass damper (TMD) to reduce body vibration. The recent patents of TMD were investigated in this research. In this paper, the coun-terweight of the excavator is designed as a non-linear TMD system. The vibration models were established under driving and crushing conditions, respectively. The vibration response of the vehicle body was calculated and analyzed through MATLAB/Simulink under driving and crush-ing conditions. Finally, the damping characteristics of the TMD system were discussed. The vibration of the car body can be reduced by TMD. 2The improvement rates in ver-tical acceleration were 8.05%, 11.85% and 11.15% for the three classes of road surfaces for the driving conditions. The improvement rates of 3vertical acceleration for the three powers of crushing conditions are 16.18%, 18.32% and 23.48%, respectively. The vibration damping performance of the excavator was effectively improved by TMD in the main working conditions. The variation of body vertical acceleration with TMD parameters indicates the existence of optimal damping characteristics parameters for the TMD system at a fixed road surface and vehicle speed.
{"title":"Research on Vibration Damping of Tuned Mass Damper for Wheeled Ex-cavator","authors":"Xin Zhang, Feitang Wang, Zhanlong Li, Jianwei Li","doi":"10.2174/2212797615666220816101151","DOIUrl":"https://doi.org/10.2174/2212797615666220816101151","url":null,"abstract":"\u0000\u0000When driving and working, the engine, working equipment and uneven road sur-face will cause severe vibrations to the wheeled excavator, 1which can affect efficiency and comfort. This paper discusses various patents and presents a new method of vibration reduction for excavators.\u0000\u0000\u0000\u0000The purpose of the research is to design the counterweight of the excavator as tuned mass of tuned mass damper (TMD) to reduce body vibration.\u0000\u0000\u0000\u0000The recent patents of TMD were investigated in this research. In this paper, the coun-terweight of the excavator is designed as a non-linear TMD system. The vibration models were established under driving and crushing conditions, respectively. The vibration response of the vehicle body was calculated and analyzed through MATLAB/Simulink under driving and crush-ing conditions. Finally, the damping characteristics of the TMD system were discussed.\u0000\u0000\u0000\u0000The vibration of the car body can be reduced by TMD. 2The improvement rates in ver-tical acceleration were 8.05%, 11.85% and 11.15% for the three classes of road surfaces for the driving conditions. The improvement rates of 3vertical acceleration for the three powers of crushing conditions are 16.18%, 18.32% and 23.48%, respectively.\u0000\u0000\u0000\u0000The vibration damping performance of the excavator was effectively improved by TMD in the main working conditions. The variation of body vertical acceleration with TMD parameters indicates the existence of optimal damping characteristics parameters for the TMD system at a fixed road surface and vehicle speed.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44216862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-16DOI: 10.2174/2212797615666220816123154
Sara Benmaziane, O. Lenda, S. Saissi, L. Zerrouk, E. Saad
Among the metals used in foundry, we find the austenitic stainless steels, which are used in several fields because of their mechanical properties, which can change during the heat treatments; for that, it is important to understand and control the growth of the austenite grains. Modeling austenite grain growth by considering the effects of heating temperature, holding time, and initial austenite grain size on austenite grain growth. In this paper, the austenite grain growth process of AISI 302 steel was studied in a temperature range of 900 to 1000 °C and a holding time of up to 360 minutes. Based on the experimental results and a combination of Arrhenius and Sellars type equations, a mathematical model of austenite grain growth was developed. From the experimental part, it was found that the increase in heating temperature caused the dissolution of carbides; therefore, the size of austenite grains grew faster, implying a higher growth rate. The prolongation of the holding time also led to the increase in the size of the austenite grains. Based on statistical indicators and a comparison between experimental and predicted results, the ability of the model to predict austenite grain growth was confirmed.
{"title":"Modeling of Austenite Grain Growth Behavior for AISI 302 Stainless Steel","authors":"Sara Benmaziane, O. Lenda, S. Saissi, L. Zerrouk, E. Saad","doi":"10.2174/2212797615666220816123154","DOIUrl":"https://doi.org/10.2174/2212797615666220816123154","url":null,"abstract":"\u0000\u0000Among the metals used in foundry, we find the austenitic stainless steels, which are used in several fields because of their mechanical properties, which can change during the heat treatments; for that, it is important to understand and control the growth of the austenite grains.\u0000\u0000\u0000\u0000Modeling austenite grain growth by considering the effects of heating temperature, holding time, and initial austenite grain size on austenite grain growth.\u0000\u0000\u0000\u0000In this paper, the austenite grain growth process of AISI 302 steel was studied in a temperature range of 900 to 1000 °C and a holding time of up to 360 minutes. Based on the experimental results and a combination of Arrhenius and Sellars type equations, a mathematical model of austenite grain growth was developed.\u0000\u0000\u0000\u0000From the experimental part, it was found that the increase in heating temperature caused the dissolution of carbides; therefore, the size of austenite grains grew faster, implying a higher growth rate. The prolongation of the holding time also led to the increase in the size of the austenite grains.\u0000\u0000\u0000\u0000Based on statistical indicators and a comparison between experimental and predicted results, the ability of the model to predict austenite grain growth was confirmed.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41430226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-05DOI: 10.2174/2212797615666220805121848
Lin Han, Shaoshuai Liu, Yang Qi, Weiguang Li
Tooth surface wear is inevitable in helical geared transmission. Consequently, the worn profile deviates from ideal involute one. As a result, the structural stiffness of worn tooth and contact stiffness of tooth-pair are both changed. This work presents an improved calculation method for structural stiffness of worn teeth by combining slicing and potential energy method, considering non-uniform distribution of wear amount along tooth surface. Then a nonlinear contact stiffness model is employed to investigate the influence of wear on contact stiffness. Meanwhile, taking wear as one kind of profile deviation, the analytical model of time-varying mesh stiffness (TVMS) of helical gear pair is derived. Furthermore, governing equations with 6 degree-of-freedom is established and influences of wear on dynamic responses are revealed. Results indicate that structural stiffness of worn teeth decreases but contact stiffness does not always keep increasing or decreasing. The fluctuation of dynamic transmission error with the nonlinear contact model is not as significant as that from constant contact stiffness model. The approach presented in this work is suitable for condition monitoring of helical gears in view of long-term service.
{"title":"Influence of tooth surface wear and nonlinear contact stiffness on dynamic responses of helical gears","authors":"Lin Han, Shaoshuai Liu, Yang Qi, Weiguang Li","doi":"10.2174/2212797615666220805121848","DOIUrl":"https://doi.org/10.2174/2212797615666220805121848","url":null,"abstract":"\u0000\u0000Tooth surface wear is inevitable in helical geared transmission. Consequently, the worn profile deviates from ideal involute one. As a result, the structural stiffness of worn tooth and contact stiffness of tooth-pair are both changed.\u0000\u0000\u0000\u0000This work presents an improved calculation method for structural stiffness of worn teeth by combining slicing and potential energy method, considering non-uniform distribution of wear amount along tooth surface. Then a nonlinear contact stiffness model is employed to investigate the influence of wear on contact stiffness. Meanwhile, taking wear as one kind of profile deviation, the analytical model of time-varying mesh stiffness (TVMS) of helical gear pair is derived. Furthermore, governing equations with 6 degree-of-freedom is established and influences of wear on dynamic responses are revealed.\u0000\u0000\u0000\u0000Results indicate that structural stiffness of worn teeth decreases but contact stiffness does not always keep increasing or decreasing. The fluctuation of dynamic transmission error with the nonlinear contact model is not as significant as that from constant contact stiffness model.\u0000\u0000\u0000\u0000The approach presented in this work is suitable for condition monitoring of helical gears in view of long-term service.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48030355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-22DOI: 10.2174/2212797615666220622092646
Liang Tang, Yang Liu
In order to efficiently exploit the hydrate reservoir, based on the problem of large amount of sand production in the current hydrate reservoir exploration process, combined with the solid fluidization well testing and production method. A gas-liquid-solid three-phase flow model is established and hydrate decomposition is taken into consideration. The changes in parameters of wellbore pressure, gas volume fraction, liquid volume fraction, temperature and the decomposition rates of wellbore hydrate under the conditions of different rates of sand production are analyzed. The results show that with the increasing rate of sand production during the solid fluidization well testing and production, pressure of the wellbore is lifted, gas volume fraction declines, liquid volume fraction declines, and temperature of the wellbore does not change. Moreover, increasing rate of sand production also leads to the delay of the position where hydrate begins to decompose. With the decrease of hydrate saturation, pressure of the wellbore goes up, gas volume fraction is lifted, solid volume fraction rises, and decomposition rate of hydrate declines.
{"title":"Influence of Solid Particles on Wellbore Parameters in Solid Fluidization Production Process","authors":"Liang Tang, Yang Liu","doi":"10.2174/2212797615666220622092646","DOIUrl":"https://doi.org/10.2174/2212797615666220622092646","url":null,"abstract":"\u0000\u0000In order to efficiently exploit the hydrate reservoir, based on the problem of large amount of sand production in the current hydrate reservoir exploration process, combined with the solid fluidization well testing and production method.\u0000\u0000\u0000\u0000A gas-liquid-solid three-phase flow model is established and hydrate decomposition is taken into consideration. The changes in parameters of wellbore pressure, gas volume fraction, liquid volume fraction, temperature and the decomposition rates of wellbore hydrate under the conditions of different rates of sand production are analyzed.\u0000\u0000\u0000\u0000The results show that with the increasing rate of sand production during the solid fluidization well testing and production, pressure of the wellbore is lifted, gas volume fraction declines, liquid volume fraction declines, and temperature of the wellbore does not change. Moreover, increasing rate of sand production also leads to the delay of the position where hydrate begins to decompose.\u0000\u0000\u0000\u0000With the decrease of hydrate saturation, pressure of the wellbore goes up, gas volume fraction is lifted, solid volume fraction rises, and decomposition rate of hydrate declines.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44119119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-22DOI: 10.2174/2212797615666220622093515
Wenqing Feng, Guoyong Zhang, Yi Ouyang, Xinyue Pi, Lifu He, Jing Luo, Lingzhi Yi, You Guo
With the rapid development of power system, oil-immersed transformers are widely used in the substation and distribution system. The faults of oil-immersed transformers are large threat to the power system. Therefore, it is significant that the faults of oil-immersed transformers can be diagnosed accurately. To accurately diagnose the faults of oil-immersed transformers through machine learning methods and swarm intelligent algorithms. To accurately diagnose the faults of oil-immersed transformers, a fault diagnosis method based on T-distributed stochastic neighbor embedding and support vector machine is proposed. The improved beetle antennae search algorithm is used to optimize the parameters of support vector machine. Firstly, the non-coding ratio method is used to obtain nine-dimensional characteristic indices. Secondly, the original nine-dimensional data are reduced to three-dimensional by T-distributed stochastic neighbor embedding. Lastly, the data after dimensionality reduction are used as the input of the support vector machine optimized by improved beetle antennae search algorithm and the fault types of transformers can be diagnosed. The accuracy rate is 94.53% and the operation time is about 1.88s. The results indicate that the method proposed by this paper is reasonable. The experimental results show that the method proposed by this paper has a high accuracy rate and low operation time. Mixed faults that are difficult to diagnose also can be diagnosed by this paper's method. In the era of big data, there is a lot of data of transformer, so the method proposed in this paper has certain engineering significance.
{"title":"Fault Diagnosis of Oil -Immersed Transformer based on TSNE and IBASA-SVM","authors":"Wenqing Feng, Guoyong Zhang, Yi Ouyang, Xinyue Pi, Lifu He, Jing Luo, Lingzhi Yi, You Guo","doi":"10.2174/2212797615666220622093515","DOIUrl":"https://doi.org/10.2174/2212797615666220622093515","url":null,"abstract":"\u0000\u0000With the rapid development of power system, oil-immersed transformers are widely used in the substation and distribution system. The faults of oil-immersed transformers are large threat to the power system. Therefore, it is significant that the faults of oil-immersed transformers can be diagnosed accurately.\u0000\u0000\u0000\u0000To accurately diagnose the faults of oil-immersed transformers through machine learning methods and swarm intelligent algorithms.\u0000\u0000\u0000\u0000To accurately diagnose the faults of oil-immersed transformers, a fault diagnosis method based on T-distributed stochastic neighbor embedding and support vector machine is proposed. The improved beetle antennae search algorithm is used to optimize the parameters of support vector machine. Firstly, the non-coding ratio method is used to obtain nine-dimensional characteristic indices. Secondly, the original nine-dimensional data are reduced to three-dimensional by T-distributed stochastic neighbor embedding. Lastly, the data after dimensionality reduction are used as the input of the support vector machine optimized by improved beetle antennae search algorithm and the fault types of transformers can be diagnosed.\u0000\u0000\u0000\u0000The accuracy rate is 94.53% and the operation time is about 1.88s. The results indicate that the method proposed by this paper is reasonable.\u0000\u0000\u0000\u0000The experimental results show that the method proposed by this paper has a high accuracy rate and low operation time. Mixed faults that are difficult to diagnose also can be diagnosed by this paper's method. In the era of big data, there is a lot of data of transformer, so the method proposed in this paper has certain engineering significance.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43376854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-15DOI: 10.2174/2212797615666220615153203
Shuaihui Sun, Z. Song, Pengcheng Guo, Xianwen Wang, Bo Zhang, Zhenkai Mao
Scroll refrigeration compressors are the critical equipment for the refrigeration system in air conditioners and vehicles. The asymmetric suction structure can be applied to reduce the scroll compressors' size. However, the pressure difference between the symmetric working chambers becomes larger and leads to the special force characteristics of the orbiting scroll. This paper illustrates the force characteristics of the orbiting scroll in an Asymmetric-suction Scroll Compressor (ASC) to improve its stability and reliability. The theoretical model has been established to calculate the force and moment acting on the orbiting scroll of ASC and the Symmetric-suction Scroll Compressor (SSC) based on the transient numerical simulation results. The variations of gas force and moment in ASC and SSC are displayed and compared. Their pulsation intensities are calculated and discussed. The pressure in the outer compression chamber of ASC was always higher than that in the inner compression chamber, which caused significant discharge loss. Affected by the tangential leakage flow, the radial force of the compressor fluctuated sharply. As the tangential force on the orbiting scroll segments of symmetrical working chambers in ASC led to the negative spin moment, the total average spin torque decreased by 71.3%. Still, the pulsation intensity increased by ten times. Furthermore, the direction of the spin moment reversed at 275°~355°, which indicated that the orbiting scroll impacted the Oldham ring every rotation. The noise and vibration would happen, and the Oldham ring would be damaged easily.
{"title":"Investigations on Force Characteristics of Orbiting Scroll in Asymmetric-suction Scroll Compressors","authors":"Shuaihui Sun, Z. Song, Pengcheng Guo, Xianwen Wang, Bo Zhang, Zhenkai Mao","doi":"10.2174/2212797615666220615153203","DOIUrl":"https://doi.org/10.2174/2212797615666220615153203","url":null,"abstract":"\u0000\u0000Scroll refrigeration compressors are the critical equipment for the refrigeration system in air conditioners and vehicles. The asymmetric suction structure can be applied to reduce the scroll compressors' size. However, the pressure difference between the symmetric working chambers becomes larger and leads to the special force characteristics of the orbiting scroll.\u0000\u0000\u0000\u0000This paper illustrates the force characteristics of the orbiting scroll in an Asymmetric-suction Scroll Compressor (ASC) to improve its stability and reliability.\u0000\u0000\u0000\u0000The theoretical model has been established to calculate the force and moment acting on the orbiting scroll of ASC and the Symmetric-suction Scroll Compressor (SSC) based on the transient numerical simulation results.\u0000\u0000\u0000\u0000The variations of gas force and moment in ASC and SSC are displayed and compared. Their pulsation intensities are calculated and discussed.\u0000\u0000\u0000\u0000The pressure in the outer compression chamber of ASC was always higher than that in the inner compression chamber, which caused significant discharge loss. Affected by the tangential leakage flow, the radial force of the compressor fluctuated sharply. As the tangential force on the orbiting scroll segments of symmetrical working chambers in ASC led to the negative spin moment, the total average spin torque decreased by 71.3%. Still, the pulsation intensity increased by ten times. Furthermore, the direction of the spin moment reversed at 275°~355°, which indicated that the orbiting scroll impacted the Oldham ring every rotation. The noise and vibration would happen, and the Oldham ring would be damaged easily.\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42853281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-06DOI: 10.2174/2212797615666220606094601
X. Song, Xiaorong Wang, Jidong Wang, H. Fu
An inverted XY-3-RPS hybrid mechanism was designed for applying ultraviolet-induced nano-particle colloid jet machining to polish complex surface. The hybrid mechanism has been widely used in ultraprecision polishing field for in-stalling different polishing tools on the moving platform to meet different machining requirements because of its wide working space, good dynamic performance and large bearing capacity. The main objective of this study is to establish an inverted XY-3-RPS hybrid mechanism for UV-induced nanoparticle colloid jet machining, to realize the ultra precision polishing of complex surfaces by UV-induced nanoparticle colloid jet machining. The three-dimensional model of the inverted XY-3-RPS hybrid mechanism was established, and the kinematics and dynamics were analyzed. The velocity Jacobian matrix of the inverted XY-3-RPS hybrid mechanism is derived by vector construction method and differential method, and the dexterity index under different proportional parameters is optimized and simulated. The output Jacobian matrix and stiffness matrix are obtained by using the virtual work principle, and their static analysis is carried out. Based on Lagrange dynamics theory, the dynamic mathematical model of inverted XY-3-RPS hybrid mechanism is established, and its kinematics is verified by software joint simulation. Through dynamic simulation, the variation curves of motion, force and kinetic energy of the mechanism are obtained, which provides a theoretical basis for the application of the hybrid mechanism in complex curved surface polishing. The analysis results show that it has the best dexterity index when the ratio of moving and fixed platform is 2:1. The kinematic simulation results show that the hybrid mechanism moves reliably under the given trajectory. The dynamic simulation results show that the force analysis of each kinematic pair and the kinetic energy change curve of each part change smoothly and the dynamic performance is stable under different trajectories. The parameter design and structural design of the inverted XY-3-RPS hybrid mechanism meets the requirements of ultra precision polishing of complex surfaces
{"title":"Design and Analysis of an Inverted XY-3RPS Hybrid Mechanism for Polishing of Complex Surface","authors":"X. Song, Xiaorong Wang, Jidong Wang, H. Fu","doi":"10.2174/2212797615666220606094601","DOIUrl":"https://doi.org/10.2174/2212797615666220606094601","url":null,"abstract":"\u0000\u0000An inverted XY-3-RPS hybrid mechanism was designed for applying ultraviolet-induced nano-particle colloid jet machining to polish complex surface.\u0000\u0000\u0000\u0000The hybrid mechanism has been widely used in ultraprecision polishing field for in-stalling different polishing tools on the moving platform to meet different machining requirements because of its wide working space, good dynamic performance and large bearing capacity.\u0000\u0000\u0000\u0000The main objective of this study is to establish an inverted XY-3-RPS hybrid mechanism for UV-induced nanoparticle colloid jet machining, to realize the ultra precision polishing of complex surfaces by UV-induced nanoparticle colloid jet machining.\u0000\u0000\u0000\u0000The three-dimensional model of the inverted XY-3-RPS hybrid mechanism was established, and the kinematics and dynamics were analyzed. The velocity Jacobian matrix of the inverted XY-3-RPS hybrid mechanism is derived by vector construction method and differential method, and the dexterity index under different proportional parameters is optimized and simulated. The output Jacobian matrix and stiffness matrix are obtained by using the virtual work principle, and their static analysis is carried out. Based on Lagrange dynamics theory, the dynamic mathematical model of inverted XY-3-RPS hybrid mechanism is established, and its kinematics is verified by software joint simulation. Through dynamic simulation, the variation curves of motion, force and kinetic energy of the mechanism are obtained, which provides a theoretical basis for the application of the hybrid mechanism in complex curved surface polishing.\u0000\u0000\u0000\u0000The analysis results show that it has the best dexterity index when the ratio of moving and fixed platform is 2:1. The kinematic simulation results show that the hybrid mechanism moves reliably under the given trajectory. The dynamic simulation results show that the force analysis of each kinematic pair and the kinetic energy change curve of each part change smoothly and the dynamic performance is stable under different trajectories.\u0000\u0000\u0000\u0000The parameter design and structural design of the inverted XY-3-RPS hybrid mechanism meets the requirements of ultra precision polishing of complex surfaces\u0000","PeriodicalId":39169,"journal":{"name":"Recent Patents on Mechanical Engineering","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48888190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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