The Experts below are selected from a list of 22137 Experts worldwide ranked by ideXlab platform
Simon C Stahler - One of the best experts on this subject based on the ideXlab platform.
-
performance report of the rhum Rum ocean bottom seismometer network around la reunion western indian ocean
Advances in Geosciences, 2016Co-Authors: W. C. Crawford, M. Tsekhmistrenko, Simon C Stahler, Karin Sigloch, Guilhem Barruol, K. Hosseini, Mechita C Schmidtaursch, Johnrobert ScholzAbstract:Abstract. RHUM-Rum is a German-French seismological experiment based on the sea floor surrounding the island of La Reunion, western Indian Ocean (Barruol and Sigloch, 2013). Its primary objective is to clarify the presence or absence of a mantle plume beneath the Reunion volcanic hotspot. RHUM-Rum's central component is a 13-month deployment (October 2012 to November 2013) of 57 broadband ocean bottom seismometers (OBS) and hydrophones over an area of 2000 × 2000 km2 surrounding the hotspot. The array contained 48 wideband OBS from the German DEPAS pool and 9 broadband OBS from the French INSU pool. It is the largest deployment of DEPAS and INSU OBS so far, and the first joint experiment. This article reviews network performance and data quality: of the 57 stations, 46 and 53 yielded good seismometer and hydrophone recordings, respectively. The 19 751 total deployment days yielded 18 735 days of hydrophone recordings and 15 941 days of seismometer recordings, which are 94 and 80 % of the theoretically possible yields. The INSU seismic sensors stand away from their OBS frames, whereas the DEPAS sensors are integrated into their frames. At long periods (> 10 s), the DEPAS seismometers are affected by significantly stronger noise than the INSU seismometers. On the horizontal components, this can be explained by tilting of the frame and buoy assemblage, e.g. through the action of ocean-bottom currents, but in addition the DEPAS intRuments are affected by significant self-noise at long periods, including on the vertical channels. By comparison, the INSU instRuments are much quieter at periods > 30 s and hence better suited for long-period signals studies. The trade-off of the instRument design is that the integrated DEPAS setup is easier to deploy and recover, especially when large numbers of stations are involved. Additionally, the wideband sensor has only half the power consumption of the broadband INSU seismometers. For the first time, this article publishes response information of the DEPAS instRuments, which is necessary for any project where true ground displacement is of interest. The data will become publicly available at the end of 2017.
-
Performance report of the RHUM-Rum ocean bottom seismometer network around la Réunion, western Indian Ocean
Advances in Geosciences, 2016Co-Authors: Simon C Stahler, W. C. Crawford, M. Tsekhmistrenko, J. R. Scholz, A. Mazzullo, Mechita C. Schmidt-aursch, Karin Sigloch, Guilhem Barruol, K. Hosseini, Mathijs DeenAbstract:RHUM-Rum is a German-French seismological experiment based on the sea floor surrounding the island of La Réunion, western Indian Ocean (Barruol and Sigloch, 2013). Its primary objective is to clarify the presence or absence of a mantle plume beneath the Reunion volcanic hotspot. RHUM-Rum's central component is a 13-month deployment (October 2012 to November 2013) of 57 broadband ocean bottom seismometers (OBS) and hydrophones over an area of 2000 × 2000 km2 surrounding the hotspot. The array contained 48 wideband OBS from the German DEPAS pool and 9 broadband OBS from the French INSU pool. It is the largest deployment of DEPAS and INSU OBS so far, and the first joint experiment. This article reviews network performance and data quality: of the 57 stations, 46 and 53 yielded good seismometer and hydrophone recordings, respectively. The 19 751 total deployment days yielded 18 735 days of hydrophone recordings and 15 941 days of seismometer recordings, which are 94 and 80 % of the theoretically possible yields. The INSU seismic sensors stand away from their OBS frames, whereas the DEPAS sensors are integrated into their frames. At long periods (> 10 s), the DEPAS seismometers are affected by significantly stronger noise than the INSU seismometers. On the horizontal components, this can be explained by tilting of the frame and buoy assemblage, e.g. through the action of ocean-bottom currents, but in addition the DEPAS intRuments are affected by significant self-noise at long periods, including on the vertical channels. By comparison, the INSU instRuments are much quieter at periods > 30 s and hence better suited for long-period signals studies. The trade-off of the instRument design is that the integrated DEPAS setup is easier to deploy and recover, especially when large numbers of stations are involved. Additionally, the wideband sensor has only half the power consumption of the broadband INSU seismometers. For the first time, this article publishes response information of the DEPAS instRuments, which is necessary for any project where true ground displacement is of interest. The data will become publicly available at the end of 2017.
Karin Sigloch - One of the best experts on this subject based on the ideXlab platform.
-
performance report of the rhum Rum ocean bottom seismometer network around la reunion western indian ocean
Advances in Geosciences, 2016Co-Authors: W. C. Crawford, M. Tsekhmistrenko, Simon C Stahler, Karin Sigloch, Guilhem Barruol, K. Hosseini, Mechita C Schmidtaursch, Johnrobert ScholzAbstract:Abstract. RHUM-Rum is a German-French seismological experiment based on the sea floor surrounding the island of La Reunion, western Indian Ocean (Barruol and Sigloch, 2013). Its primary objective is to clarify the presence or absence of a mantle plume beneath the Reunion volcanic hotspot. RHUM-Rum's central component is a 13-month deployment (October 2012 to November 2013) of 57 broadband ocean bottom seismometers (OBS) and hydrophones over an area of 2000 × 2000 km2 surrounding the hotspot. The array contained 48 wideband OBS from the German DEPAS pool and 9 broadband OBS from the French INSU pool. It is the largest deployment of DEPAS and INSU OBS so far, and the first joint experiment. This article reviews network performance and data quality: of the 57 stations, 46 and 53 yielded good seismometer and hydrophone recordings, respectively. The 19 751 total deployment days yielded 18 735 days of hydrophone recordings and 15 941 days of seismometer recordings, which are 94 and 80 % of the theoretically possible yields. The INSU seismic sensors stand away from their OBS frames, whereas the DEPAS sensors are integrated into their frames. At long periods (> 10 s), the DEPAS seismometers are affected by significantly stronger noise than the INSU seismometers. On the horizontal components, this can be explained by tilting of the frame and buoy assemblage, e.g. through the action of ocean-bottom currents, but in addition the DEPAS intRuments are affected by significant self-noise at long periods, including on the vertical channels. By comparison, the INSU instRuments are much quieter at periods > 30 s and hence better suited for long-period signals studies. The trade-off of the instRument design is that the integrated DEPAS setup is easier to deploy and recover, especially when large numbers of stations are involved. Additionally, the wideband sensor has only half the power consumption of the broadband INSU seismometers. For the first time, this article publishes response information of the DEPAS instRuments, which is necessary for any project where true ground displacement is of interest. The data will become publicly available at the end of 2017.
-
Performance report of the RHUM-Rum ocean bottom seismometer network around la Réunion, western Indian Ocean
Advances in Geosciences, 2016Co-Authors: Simon C Stahler, W. C. Crawford, M. Tsekhmistrenko, J. R. Scholz, A. Mazzullo, Mechita C. Schmidt-aursch, Karin Sigloch, Guilhem Barruol, K. Hosseini, Mathijs DeenAbstract:RHUM-Rum is a German-French seismological experiment based on the sea floor surrounding the island of La Réunion, western Indian Ocean (Barruol and Sigloch, 2013). Its primary objective is to clarify the presence or absence of a mantle plume beneath the Reunion volcanic hotspot. RHUM-Rum's central component is a 13-month deployment (October 2012 to November 2013) of 57 broadband ocean bottom seismometers (OBS) and hydrophones over an area of 2000 × 2000 km2 surrounding the hotspot. The array contained 48 wideband OBS from the German DEPAS pool and 9 broadband OBS from the French INSU pool. It is the largest deployment of DEPAS and INSU OBS so far, and the first joint experiment. This article reviews network performance and data quality: of the 57 stations, 46 and 53 yielded good seismometer and hydrophone recordings, respectively. The 19 751 total deployment days yielded 18 735 days of hydrophone recordings and 15 941 days of seismometer recordings, which are 94 and 80 % of the theoretically possible yields. The INSU seismic sensors stand away from their OBS frames, whereas the DEPAS sensors are integrated into their frames. At long periods (> 10 s), the DEPAS seismometers are affected by significantly stronger noise than the INSU seismometers. On the horizontal components, this can be explained by tilting of the frame and buoy assemblage, e.g. through the action of ocean-bottom currents, but in addition the DEPAS intRuments are affected by significant self-noise at long periods, including on the vertical channels. By comparison, the INSU instRuments are much quieter at periods > 30 s and hence better suited for long-period signals studies. The trade-off of the instRument design is that the integrated DEPAS setup is easier to deploy and recover, especially when large numbers of stations are involved. Additionally, the wideband sensor has only half the power consumption of the broadband INSU seismometers. For the first time, this article publishes response information of the DEPAS instRuments, which is necessary for any project where true ground displacement is of interest. The data will become publicly available at the end of 2017.
C. Treadwell - One of the best experts on this subject based on the ideXlab platform.
-
Rotary ultrasonic machining of CFRP composites: A study on power consumption
Ultrasonics, 2012Co-Authors: W.l. Cong, Anil Srivastava, L. Riley, Z.j. Pei, Timothy W Deines, C. TreadwellAbstract:Carbon fiber reinforced plastic (CFRP) composites are very difficult to machine. A large number of holes need to be drilled in CFRP for many applications. Therefore, it is important to develop cost-effective drilling processes. CFRP has been drilled by rotary ultrasonic machining (Rum) successfully. The literature has reports about the effects of input variables on output variables (including cutting force, torque, surface roughness, tool wear, and workpiece delamination) in Rum of CFRP. However, there are no reports on power consumption in Rum of CFRP. This paper reports the first study on power consumption in Rum of CFRP. It reports an experimental investigation on effects of input variables (ultrasonic power, tool rotation speed, feedrate, and type of CFRP) on power consumption of each component (including ultrasonic power supply, spindle motor, coolant pump, and air compressor) and the entire Rum system. © 2012 Elsevier B.V. All rights reserved.
-
Study on Edge Chipping in Rotary Ultrasonic Machining of Ceramics: An Integration of Designed Experiments and Finite Element Method Analysis
Journal of Manufacturing Science and Engineering, 2005Co-Authors: Yue Jiao, X. J. Xin, Z.j. Pei, W J Liu, C. TreadwellAbstract:Rotary ultrasonic machining (Rum) is a relatively low cost and environmentally benign process for machining of advanced ceramics. Much effort has been made to theoretically and experimentally investigate material removal rate, surface roughness, and tool wear in Rum. However, there is no report on systematic study of edge chipping in Rum drilling of ceramics. This paper presents the results of a study on edge chipping in Rum drilling of advanced ceramics. The study is conducted by an integrated approach, combining designed experiments and FEM (finite element method) analysis. The designed experiments will reveal the main effects as well as interaction effects of process variables (spindle speed, ultrasonic power, feedrate, and grit size) on cutting force and chipping thickness. FEM simulations will provide the stress and strain distributions in the workpiece while being drilled by Rum. Furthermore, the relationship between chipping thickness and cutting force obtained from the FEM simulations will be compared with that obtained from the designed experiments. DOI: 10.1115/1.2034511
-
Experimental observation of tool wear in rotary ultrasonic machining of advanced ceramics
International Journal of Machine Tools and Manufacture, 2005Co-Authors: W.m. Zeng, Z.j. Pei, Z C Li, C. TreadwellAbstract:As one of the cost-effective machining methods for advanced ceramics, rotary ultrasonic machining (Rum) has attracted much attention and there exist numerous publications on the process. However, few investigations on tool wear in the Rum process have been reported. This paper, for the first time in literature, presents an experimental observation on tool wear in Rum of silicon carbide (SiC). It first reviews some related wear mechanisms for grinding wheels and some techniques for studying the wheel wear mechanisms. After describing the experimental procedures, it presents and discusses the results on tool wear and cutting forces in Rum of SiC. It also discusses some practical implications of the findings from this study.
Z.j. Pei - One of the best experts on this subject based on the ideXlab platform.
-
Rotary ultrasonic machining of cfrp: A mechanistic predictive model for cutting force
Ultrasonics, 2014Co-Authors: W.l. Cong, Z.j. Pei, Chong Zhang, C L ZhangAbstract:Cutting force is one of the most important output variables in rotary ultrasonic machining (Rum) of carbon fiber reinforced plastic (CFRP) composites. Many experimental investigations on cutting force in Rum of CFRP have been reported. However, in the literature, there are no cutting force models for Rum of CFRP. This paper develops a mechanistic predictive model for cutting force in Rum of CFRP. The material removal mechanism of CFRP in Rum has been analyzed first. The model is based on the assumption that brittle fracture is the dominant mode of material removal. CFRP micromechanical analysis has been conducted to represent CFRP as an equivalent homogeneous material to obtain the mechanical properties of CFRP from its components. Based on this model, relationships between input variables (including ultrasonic vibration amplitude, tool rotation speed, feedrate, abrasive size, and abrasive concentration) and cutting force can be predicted. The relationships between input variables and important intermediate variables (indentation depth, effective contact time, and maximum impact force of single abrasive grain) have been investigated to explain predicted trends of cutting force. Experiments are conducted to verify the model, and experimental results agree well with predicted trends from this model. ?? 2013 Elsevier B.V. All rights reserved.
-
cutting temperature in rotary ultrasonic machining of titanium experimental study using novel fabry perot fibre optic sensors
International Journal of Manufacturing Research, 2013Co-Authors: Xiaotian Zou, Z.j. Pei, Weilong Cong, Nan Wu, Ye Tian, Xingwei WangAbstract:Titanium has a wide variety of applications, particularly in the aerospace industry. However, because of its low thermal conductivity and high strength, machining of titanium is very difficult. The heat generated in machining can dramatically shorten the tool life. Rotary ultrasonic machining (Rum) is a non-traditional machining process, and has been used to machine various difficult-to-machine materials. Investigations have been reported regarding effects of machining variables (including ultrasonic power, tool rotation speed, and feedrate) on several output variables in Rum, such as cutting force, torque, surface roughness, edge chipping, material removal rate, and tool wear. However, there have been few studies on cutting temperatures in Rum. This paper presents an experimental study on cutting temperature in Rum of titanium. It is the first study to utilise fibre optic temperature sensors to measure the cutting temperature in Rum. The results revealed effects of machining variables on cutting temperat...
-
A cutting force model for rotary ultrasonic machining of brittle materials
International Journal of Machine Tools and Manufacture, 2012Co-Authors: Defu Liu, W.l. Cong, Z.j. Pei, Yongjun TangAbstract:Knowing cutting force in rotary ultrasonic machining (Rum) can help optimizing input variables. Rum of brittle materials has been investigated both experimentally and theoretically. However, there are no reports on cutting force models for Rum of brittle materials. This paper presents a mechanistic model for cutting force in Rum of brittle materials. Assuming that brittle fracture is the primary mechanism of material removal in Rum of brittle materials, the cutting force model is developed step by step. On the basis of this mechanistic model, relationships between cutting force and input variables (such as spindle speed, feed rate, ultrasonic vibration amplitude, abrasive size, and abrasive concentration) are predicted. Experiments are conducted for model verification and experimental results agree well with model predictions. © 2011 Elsevier Ltd. Allrightsreserved.
-
Rotary ultrasonic machining of CFRP composites: A study on power consumption
Ultrasonics, 2012Co-Authors: W.l. Cong, Anil Srivastava, L. Riley, Z.j. Pei, Timothy W Deines, C. TreadwellAbstract:Carbon fiber reinforced plastic (CFRP) composites are very difficult to machine. A large number of holes need to be drilled in CFRP for many applications. Therefore, it is important to develop cost-effective drilling processes. CFRP has been drilled by rotary ultrasonic machining (Rum) successfully. The literature has reports about the effects of input variables on output variables (including cutting force, torque, surface roughness, tool wear, and workpiece delamination) in Rum of CFRP. However, there are no reports on power consumption in Rum of CFRP. This paper reports the first study on power consumption in Rum of CFRP. It reports an experimental investigation on effects of input variables (ultrasonic power, tool rotation speed, feedrate, and type of CFRP) on power consumption of each component (including ultrasonic power supply, spindle motor, coolant pump, and air compressor) and the entire Rum system. © 2012 Elsevier B.V. All rights reserved.
-
Study on Edge Chipping in Rotary Ultrasonic Machining of Ceramics: An Integration of Designed Experiments and Finite Element Method Analysis
Journal of Manufacturing Science and Engineering, 2005Co-Authors: Yue Jiao, X. J. Xin, Z.j. Pei, W J Liu, C. TreadwellAbstract:Rotary ultrasonic machining (Rum) is a relatively low cost and environmentally benign process for machining of advanced ceramics. Much effort has been made to theoretically and experimentally investigate material removal rate, surface roughness, and tool wear in Rum. However, there is no report on systematic study of edge chipping in Rum drilling of ceramics. This paper presents the results of a study on edge chipping in Rum drilling of advanced ceramics. The study is conducted by an integrated approach, combining designed experiments and FEM (finite element method) analysis. The designed experiments will reveal the main effects as well as interaction effects of process variables (spindle speed, ultrasonic power, feedrate, and grit size) on cutting force and chipping thickness. FEM simulations will provide the stress and strain distributions in the workpiece while being drilled by Rum. Furthermore, the relationship between chipping thickness and cutting force obtained from the FEM simulations will be compared with that obtained from the designed experiments. DOI: 10.1115/1.2034511
Mathijs Deen - One of the best experts on this subject based on the ideXlab platform.
-
Performance report of the RHUM-Rum ocean bottom seismometer network around la Réunion, western Indian Ocean
Advances in Geosciences, 2016Co-Authors: Simon C Stahler, W. C. Crawford, M. Tsekhmistrenko, J. R. Scholz, A. Mazzullo, Mechita C. Schmidt-aursch, Karin Sigloch, Guilhem Barruol, K. Hosseini, Mathijs DeenAbstract:RHUM-Rum is a German-French seismological experiment based on the sea floor surrounding the island of La Réunion, western Indian Ocean (Barruol and Sigloch, 2013). Its primary objective is to clarify the presence or absence of a mantle plume beneath the Reunion volcanic hotspot. RHUM-Rum's central component is a 13-month deployment (October 2012 to November 2013) of 57 broadband ocean bottom seismometers (OBS) and hydrophones over an area of 2000 × 2000 km2 surrounding the hotspot. The array contained 48 wideband OBS from the German DEPAS pool and 9 broadband OBS from the French INSU pool. It is the largest deployment of DEPAS and INSU OBS so far, and the first joint experiment. This article reviews network performance and data quality: of the 57 stations, 46 and 53 yielded good seismometer and hydrophone recordings, respectively. The 19 751 total deployment days yielded 18 735 days of hydrophone recordings and 15 941 days of seismometer recordings, which are 94 and 80 % of the theoretically possible yields. The INSU seismic sensors stand away from their OBS frames, whereas the DEPAS sensors are integrated into their frames. At long periods (> 10 s), the DEPAS seismometers are affected by significantly stronger noise than the INSU seismometers. On the horizontal components, this can be explained by tilting of the frame and buoy assemblage, e.g. through the action of ocean-bottom currents, but in addition the DEPAS intRuments are affected by significant self-noise at long periods, including on the vertical channels. By comparison, the INSU instRuments are much quieter at periods > 30 s and hence better suited for long-period signals studies. The trade-off of the instRument design is that the integrated DEPAS setup is easier to deploy and recover, especially when large numbers of stations are involved. Additionally, the wideband sensor has only half the power consumption of the broadband INSU seismometers. For the first time, this article publishes response information of the DEPAS instRuments, which is necessary for any project where true ground displacement is of interest. The data will become publicly available at the end of 2017.
