Pub Date : 2019-03-01DOI: 10.20855/IJAV.2019.24.1E91
M. Pawełczyk
{"title":"Can we find active noise control in everyday life soon?","authors":"M. Pawełczyk","doi":"10.20855/IJAV.2019.24.1E91","DOIUrl":"https://doi.org/10.20855/IJAV.2019.24.1E91","url":null,"abstract":"","PeriodicalId":18217,"journal":{"name":"March 16","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74365942","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 : 2019-03-01DOI: 10.20855/ijav.2019.24.11140
A. Katunin
Modern mechanical and civil structures are increasingly designed using polymeric composites that ensure great strength-to-mass ratio and are resistant to various environmental interactions, like corrosion. The application of sandwich structures in the design of mechanical and civil constructions is determined by their good stiffness properties and very low mass, which is a very attractive combination. Due to their wide applicability, these structures should be properly maintained and diagnosed, and thus, appropriate non-destructive testing (NDT) methods should be developed in order to detect and identify various types of damage. Special attention should be paid to internal damage (damage to the core of a sandwich structure), which cannot be detected during a visual inspection. In the paper, an NDT method based on modal analysis and further processing of modal shapes using a wavelet transform is proposed. Three sandwich structures with damage to the core of various types were experimentally tested using modal analysis, the damage positions were detected and identified using wavelet analysis, and verified by comparing the results of previously performed thermographic tests. The obtained results show a high effectiveness of the proposed approach, which could find an application in the industrial inspection of sandwich structures in a non-destructive and non-contact manner.
{"title":"Vibration-Based Non-Destructive Evaluation of Internal Damage in Foam Cored Sandwich Structures Using Wavelet Analysis","authors":"A. Katunin","doi":"10.20855/ijav.2019.24.11140","DOIUrl":"https://doi.org/10.20855/ijav.2019.24.11140","url":null,"abstract":"Modern mechanical and civil structures are increasingly designed using polymeric composites that ensure great\u0000strength-to-mass ratio and are resistant to various environmental interactions, like corrosion. The application of\u0000sandwich structures in the design of mechanical and civil constructions is determined by their good stiffness properties and very low mass, which is a very attractive combination. Due to their wide applicability, these structures\u0000should be properly maintained and diagnosed, and thus, appropriate non-destructive testing (NDT) methods should\u0000be developed in order to detect and identify various types of damage. Special attention should be paid to internal\u0000damage (damage to the core of a sandwich structure), which cannot be detected during a visual inspection. In the\u0000paper, an NDT method based on modal analysis and further processing of modal shapes using a wavelet transform is proposed. Three sandwich structures with damage to the core of various types were experimentally tested\u0000using modal analysis, the damage positions were detected and identified using wavelet analysis, and verified by\u0000comparing the results of previously performed thermographic tests. The obtained results show a high effectiveness\u0000of the proposed approach, which could find an application in the industrial inspection of sandwich structures in a\u0000non-destructive and non-contact manner.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86085883","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 : 2019-03-01DOI: 10.20855/IJAV.2019.24.11263
Y. Beni, M. K. Zeverdejani
Protein microtubules are one of the most effective intracellular components. The microtubules structure is in a manner that their behaviour is similar to that of the orthotropic materials. Therefore, in this paper, size-dependent vibration of the anisotropic protein microtubule is studied. For this purpose, using a first shear deformable shell model and based on couple stress theory, new equations are developed for the dynamic behavior of anisotropic protein microtubule. After solving the governing equations of microtubule motion, the effects of cytoplasm environment, microtubule dimensions and its mechanical properties, and material length scale parameters on the natural frequency of microtubules are investigated.
{"title":"Using a New Size Dependent Orthotropic Elastic Shell Model for the Investigation of Free Vibration of Protein Microtubules","authors":"Y. Beni, M. K. Zeverdejani","doi":"10.20855/IJAV.2019.24.11263","DOIUrl":"https://doi.org/10.20855/IJAV.2019.24.11263","url":null,"abstract":"Protein microtubules are one of the most effective intracellular components. The microtubules structure is in a\u0000manner that their behaviour is similar to that of the orthotropic materials. Therefore, in this paper, size-dependent\u0000vibration of the anisotropic protein microtubule is studied. For this purpose, using a first shear deformable shell\u0000model and based on couple stress theory, new equations are developed for the dynamic behavior of anisotropic\u0000protein microtubule. After solving the governing equations of microtubule motion, the effects of cytoplasm environment, microtubule dimensions and its mechanical properties, and material length scale parameters on the\u0000natural frequency of microtubules are investigated.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74108478","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 : 2019-03-01DOI: 10.20855/IJAV.2019.24.11143
T. Du, Ning Chu, Linlin Cao, T. Miao, Dazhuan Wu
A water muffler is used for the noise control of a hydraulic pipeline with an external gear pump. An experimental system is established to investigate the acoustic performance of the water muffler, in which the gear pump is utilized as the sound source and power supply. Comparisons between the experimental results of the reference tube, rubber tube, and water mufflers with different inner structures have been made. Numerical simulations on the rubber tube and different water mufflers with various inner structures have been conducted. Simulation results have been compared with the experimental results. These comparison results show that the rubber tube with a compliant wall substantially contributes to the reduction of the noise generated by the gear pump, especially at the high frequency band and relatively low rotate speed of the gear pump. The water muffler results in the enhancement of the noise reduction effect on the rubber tube. With the speed of the gear pump increasing from 1172 r/min to 2344 r/min, the effect of the noise reduction becomes much weaker, since the flow-induced noise gets more intensified. For the rubber tube, in particular, the sound pressure level gets close to that of the reference tube at the speed of 2344 r/min. Moreover, it has been proven by another important experimental result that the length of the inner structure can play a critical role to the flow noise generation.
{"title":"Study on Acoustic Performance of a Water Muffler for Gear Pump","authors":"T. Du, Ning Chu, Linlin Cao, T. Miao, Dazhuan Wu","doi":"10.20855/IJAV.2019.24.11143","DOIUrl":"https://doi.org/10.20855/IJAV.2019.24.11143","url":null,"abstract":"A water muffler is used for the noise control of a hydraulic pipeline with an external gear pump. An experimental system is established to investigate the acoustic performance of the water muffler, in which the gear pump is utilized as the sound source and power supply. Comparisons between the experimental results of the reference tube, rubber tube, and water mufflers with different inner structures have been made. Numerical simulations on the rubber tube and different water mufflers with various inner structures have been conducted. Simulation results have been compared with the experimental results. These comparison results show that the rubber tube with a compliant wall substantially contributes to the reduction of the noise generated by the gear pump, especially at the high frequency band and relatively low rotate speed of the gear pump. The water muffler results in the enhancement of the noise reduction effect on the rubber tube. With the speed of the gear pump increasing from 1172 r/min to 2344 r/min, the effect of the noise reduction becomes much weaker, since the flow-induced noise gets more intensified. For the rubber tube, in particular, the sound pressure level gets close to that of the reference tube at the speed of 2344 r/min. Moreover, it has been proven by another important experimental result that the length of the inner structure can play a critical role to the flow noise generation.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81196279","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 : 2019-03-01DOI: 10.20855/IJAV.2019.24.11147
Hui Chen, Ji Wang, Jianke Du, Jia-shi Yang
We propose a new structure for piezoelectric gyroscopes. It is made from multilayered thin films of AlN or ZnO with alternating c-axes along the film thickness. It is shown theoretically that when such a film is electrically driven into higher-order overtone thickness-shear vibration in one of the two in-plane directions of the film and is rotating about the film normal, the Coriolis force due to the rotation causes a higher-order overtone thicknessshear vibration in a perpendicular direction with an electrical output that can be used to measure the angular rate of the rotation. Different from existing thickness-shear mode piezoelectric gyroscopes which are based on the fundamental or the second overtone thickness-shear mode, the proposed gyroscope operates with higher-order overtone thickness-shear modes with higher frequencies and hence potentially higher sensitivity. Because of the overtone modes, the Coriolis force acting on the gyroscope forms a self-equilibrated system and does not transmit a net force or torque to the mounting structure. This implies higher device quality factor and better performance.
{"title":"Higher-Order Overtone Thickness-Shear Vibrations of Multilayered Thin-Film Acoustic Wave Resonators and Angular Rate Sensing","authors":"Hui Chen, Ji Wang, Jianke Du, Jia-shi Yang","doi":"10.20855/IJAV.2019.24.11147","DOIUrl":"https://doi.org/10.20855/IJAV.2019.24.11147","url":null,"abstract":"We propose a new structure for piezoelectric gyroscopes. It is made from multilayered thin films of AlN or ZnO\u0000with alternating c-axes along the film thickness. It is shown theoretically that when such a film is electrically\u0000driven into higher-order overtone thickness-shear vibration in one of the two in-plane directions of the film and\u0000is rotating about the film normal, the Coriolis force due to the rotation causes a higher-order overtone thicknessshear vibration in a perpendicular direction with an electrical output that can be used to measure the angular rate\u0000of the rotation. Different from existing thickness-shear mode piezoelectric gyroscopes which are based on the\u0000fundamental or the second overtone thickness-shear mode, the proposed gyroscope operates with higher-order\u0000overtone thickness-shear modes with higher frequencies and hence potentially higher sensitivity. Because of the\u0000overtone modes, the Coriolis force acting on the gyroscope forms a self-equilibrated system and does not transmit\u0000a net force or torque to the mounting structure. This implies higher device quality factor and better performance.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90965938","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 : 2019-03-01DOI: 10.20855//ijav.2019.24.11272
M. Gohari, A. Kord, H. Jalali
Unbalance is an important fault that can damage or shut down vital rotary systems such as the gas turbine, compressors, and others, so to avoid this trouble, the balancing process is very crucial, even though it is time-consuming and costly. Thus, having a technique which can predict the unbalance location and its parameters will be valuable and practical. The current study represents a model that can identify the unbalance’s mass, radius, and location of the eccentric mass based on the artificial neural network (ANN) model. The inputs of the proposed ANN, which is based on a feed forward with back propagation model, is the bearing acceleration signal in the frequency domain. It has 10 hidden layers with 10 neurons through each layer. The accuracy in prediction was acquired at 96%, 96%, and 94% for the disc number (plane), the eccentric radius, and eccentric mass values, respectively.
{"title":"Unbalance Rotor Parameters Detection Based on Artificial Neural Network","authors":"M. Gohari, A. Kord, H. Jalali","doi":"10.20855//ijav.2019.24.11272","DOIUrl":"https://doi.org/10.20855//ijav.2019.24.11272","url":null,"abstract":"Unbalance is an important fault that can damage or shut down vital rotary systems such as the gas turbine, compressors, and others, so to avoid this trouble, the balancing process is very crucial, even though it is time-consuming\u0000and costly. Thus, having a technique which can predict the unbalance location and its parameters will be valuable\u0000and practical. The current study represents a model that can identify the unbalance’s mass, radius, and location of\u0000the eccentric mass based on the artificial neural network (ANN) model. The inputs of the proposed ANN, which is\u0000based on a feed forward with back propagation model, is the bearing acceleration signal in the frequency domain.\u0000It has 10 hidden layers with 10 neurons through each layer. The accuracy in prediction was acquired at 96%, 96%,\u0000and 94% for the disc number (plane), the eccentric radius, and eccentric mass values, respectively.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87473761","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 : 2019-03-01DOI: 10.20855/ijav.2019.24.11108
M. Bhiwapurkar, V. Saran, S. Harsha
The low frequency vibration transmitted to the body can affect the comfort, performance, and health of humans. In this paper, the effect of variations in posture and vibration magnitude on the head motion in three translational axes (fore-and-aft, lateral and vertical) has been studied with a vertical seat vibration. Thirty healthy male subjects were exposed to random vibration with three vibration magnitudes of 0.4, 0.8, and 1.2 m/s2 rms over the frequency range of 1–20 Hz. The results are analysed in terms of seat-to-head-transmissibility (STHT) for the head motions in two seated postures (backrest and leaning forward on table). The measurement of the head motion was made with an apparatus (bite-bar) specifically developed for this purpose. The measured responses to a single axis seat vibration have also shown notable cross-axis responses in both vertical and fore-and-aft axes for both postures. The crossaxis fore-aft and vertical STHT responses showed single peak near 5 Hz in both postures. An increasing intensity of vibration yields a non-linear softening effect in the muscle tension, particularly in the presence of back support, however, the body stiffens under a greater upper body motion in the forward leaning posture. The combined effect of the unsupported back and hands support was observed to be more pronounced around the resonance peak in the forward lean posture.
{"title":"Seat to Head Transmissibility during Exposure to Vertical Seat Vibration: Effects of Posture and Vibration Magnitude","authors":"M. Bhiwapurkar, V. Saran, S. Harsha","doi":"10.20855/ijav.2019.24.11108","DOIUrl":"https://doi.org/10.20855/ijav.2019.24.11108","url":null,"abstract":"The low frequency vibration transmitted to the body can affect the comfort, performance, and health of humans. In\u0000this paper, the effect of variations in posture and vibration magnitude on the head motion in three translational axes\u0000(fore-and-aft, lateral and vertical) has been studied with a vertical seat vibration. Thirty healthy male subjects were\u0000exposed to random vibration with three vibration magnitudes of 0.4, 0.8, and 1.2 m/s2\u0000rms over the frequency range\u0000of 1–20 Hz. The results are analysed in terms of seat-to-head-transmissibility (STHT) for the head motions in two\u0000seated postures (backrest and leaning forward on table). The measurement of the head motion was made with an\u0000apparatus (bite-bar) specifically developed for this purpose. The measured responses to a single axis seat vibration\u0000have also shown notable cross-axis responses in both vertical and fore-and-aft axes for both postures. The crossaxis fore-aft and vertical STHT responses showed single peak near 5 Hz in both postures. An increasing intensity\u0000of vibration yields a non-linear softening effect in the muscle tension, particularly in the presence of back support,\u0000however, the body stiffens under a greater upper body motion in the forward leaning posture. The combined effect\u0000of the unsupported back and hands support was observed to be more pronounced around the resonance peak in the\u0000forward lean posture.","PeriodicalId":18217,"journal":{"name":"March 16","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74245754","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 : 1988-12-31DOI: 10.1515/9783112480823-027
R. Kosinski
{"title":"On the Stabilization of a Vertical Bloch Line Fair in a Domain Wall in an Ion-Implanted Garnet Film","authors":"R. Kosinski","doi":"10.1515/9783112480823-027","DOIUrl":"https://doi.org/10.1515/9783112480823-027","url":null,"abstract":"","PeriodicalId":18217,"journal":{"name":"March 16","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1988-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73257883","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 : 1988-12-31DOI: 10.1515/9783112480823-012
R. Sommerfeldt, L. Holtmann, E. Krätzig, B. C. Grabmaier
{"title":"Influence of Mg Doping and Composition on the Light-Induced Charge Transport in LiNbO2","authors":"R. Sommerfeldt, L. Holtmann, E. Krätzig, B. C. Grabmaier","doi":"10.1515/9783112480823-012","DOIUrl":"https://doi.org/10.1515/9783112480823-012","url":null,"abstract":"","PeriodicalId":18217,"journal":{"name":"March 16","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1988-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85092007","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 : 1988-12-31DOI: 10.1515/9783112480823-043
J. Szatkowski, K. Sieraňski
{"title":"Influence of Interface States on the Electrical Properties 21 of Mg-Zn3P2 Junctions","authors":"J. Szatkowski, K. Sieraňski","doi":"10.1515/9783112480823-043","DOIUrl":"https://doi.org/10.1515/9783112480823-043","url":null,"abstract":"","PeriodicalId":18217,"journal":{"name":"March 16","volume":"2014 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1988-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86499424","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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