Pub Date : 2001-03-16DOI: 10.1109/MEMSYS.2001.906610
M. Mita, M. Arai, S. Tensaka, D. Kobayashi, P. Basset, A. Kaiser, P. Masquelier, L. Buchaillot, D. Collard, H. Fujita
A fully packagable micromachined actuator was developed for generating precise but unlimited displacement. A suspended silicon mass is encapsulated between glass plates and driven by electrostatic force. By hitting a stopper, it generates impact force to drive the whole actuator in a small step (/spl sim/10 nm). It is a micromachined and electrostatic version of the impact-drive actuator.
{"title":"Electrostatic impact-drive microactuator","authors":"M. Mita, M. Arai, S. Tensaka, D. Kobayashi, P. Basset, A. Kaiser, P. Masquelier, L. Buchaillot, D. Collard, H. Fujita","doi":"10.1109/MEMSYS.2001.906610","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906610","url":null,"abstract":"A fully packagable micromachined actuator was developed for generating precise but unlimited displacement. A suspended silicon mass is encapsulated between glass plates and driven by electrostatic force. By hitting a stopper, it generates impact force to drive the whole actuator in a small step (/spl sim/10 nm). It is a micromachined and electrostatic version of the impact-drive actuator.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121251281","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906552
B. Warneke, B. Atwood, K. Pister
We have demonstrated a 138 mm/sup 3/ autonomous uni-directional sensing/communication mote that optically transmits a measure of the ambient light level. We have also developed a 63 mm/sup 3/ autonomous bi-directional communication mote that receives an optical signal, generates a pseudorandom sequence based on this signal to emulate sensor data, then optically transmits the result, although it has only been demonstrated in a bench configuration at this time. The latter system contains a micromachined corner cube reflector, a 0.078 mm/sup 3/ CMOS chip that consumes 75 /spl mu/W, and a Mn-Ti-Li cell, but we have also demonstrated operation from an /spl sim/2 mm/sup 2/ solar cell. These motes allow us to demonstrate necessary concepts of Smart Dust such as optical data transmission, data processing, energy management, miniaturization, and system integration.
{"title":"Smart dust mote forerunners","authors":"B. Warneke, B. Atwood, K. Pister","doi":"10.1109/MEMSYS.2001.906552","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906552","url":null,"abstract":"We have demonstrated a 138 mm/sup 3/ autonomous uni-directional sensing/communication mote that optically transmits a measure of the ambient light level. We have also developed a 63 mm/sup 3/ autonomous bi-directional communication mote that receives an optical signal, generates a pseudorandom sequence based on this signal to emulate sensor data, then optically transmits the result, although it has only been demonstrated in a bench configuration at this time. The latter system contains a micromachined corner cube reflector, a 0.078 mm/sup 3/ CMOS chip that consumes 75 /spl mu/W, and a Mn-Ti-Li cell, but we have also demonstrated operation from an /spl sim/2 mm/sup 2/ solar cell. These motes allow us to demonstrate necessary concepts of Smart Dust such as optical data transmission, data processing, energy management, miniaturization, and system integration.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117148253","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906555
K. Böhringer, U. Srinivasan, Roger T. Howe
Massively parallel self-assembly is emerging as an efficient, low-cost alternative to conventional pick-and-place assembly of microfabricated components. The fluidic self-assembly technique we have developed exploits hydrophobic-hydrophilic surface patterning and capillary forces of an adhesive liquid between binding sites to drive the assembly process. To achieve high alignment yield, the desired assembly configuration must be a (global) energy minimum, while other (local) energy minima corresponding to undesired configurations should be avoided. Thus, the design of an effective fluidic self-assembly system using this technique requires an understanding of the interfacial phenomena involved in capillary forces; improvement of its performance involves the global optimization of design parameters such as binding site shapes and surface chemistry. This paper presents a model and computational tools for the efficient analysis and simulation of fluidic self-assembly. The strong, close range attractive forces that govern our fluidic self-assembly technique are approximated by a purely geometric model, which allows the application of efficient algorithms to predict system behavior. Various binding site designs are analyzed, and the results are compared with experimental observations. For a given binding site design, the model predicts the outcome of the self assembly process by determining minimum energy configurations and detecting unwanted local minima, thus estimating expected yield. These results can be employed toward the design of more efficient self-assembly systems.
{"title":"Modeling of capillary forces and binding sites for fluidic self-assembly","authors":"K. Böhringer, U. Srinivasan, Roger T. Howe","doi":"10.1109/MEMSYS.2001.906555","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906555","url":null,"abstract":"Massively parallel self-assembly is emerging as an efficient, low-cost alternative to conventional pick-and-place assembly of microfabricated components. The fluidic self-assembly technique we have developed exploits hydrophobic-hydrophilic surface patterning and capillary forces of an adhesive liquid between binding sites to drive the assembly process. To achieve high alignment yield, the desired assembly configuration must be a (global) energy minimum, while other (local) energy minima corresponding to undesired configurations should be avoided. Thus, the design of an effective fluidic self-assembly system using this technique requires an understanding of the interfacial phenomena involved in capillary forces; improvement of its performance involves the global optimization of design parameters such as binding site shapes and surface chemistry. This paper presents a model and computational tools for the efficient analysis and simulation of fluidic self-assembly. The strong, close range attractive forces that govern our fluidic self-assembly technique are approximated by a purely geometric model, which allows the application of efficient algorithms to predict system behavior. Various binding site designs are analyzed, and the results are compared with experimental observations. For a given binding site design, the model predicts the outcome of the self assembly process by determining minimum energy configurations and detecting unwanted local minima, thus estimating expected yield. These results can be employed toward the design of more efficient self-assembly systems.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124941916","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906605
L. Que, L. Otradovec, A. Oliver, Y. Gianchandani
This paper reports on lifetime studies of polysilicon and p/sup ++/ Si electrothermal actuators designed for rectilinear displacements. Measurements show that degradation patterns for displacement amplitude can be linked to design variables and operating conditions. At low power levels (which result in average operating temperatures of 300-400/spl deg/C), both types of devices provide continuous DC actuation for >1400 min. and pulse actuation for >30 million cycles without change in amplitude. A model similar to that used for fatigue in steel is used to fit pulse test data for p/sup ++/ Si actuators. The model parameters are explored as functions of operating conditions and device geometry.
{"title":"Pulse and DC operation lifetimes of bent-beam electrothermal actuators","authors":"L. Que, L. Otradovec, A. Oliver, Y. Gianchandani","doi":"10.1109/MEMSYS.2001.906605","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906605","url":null,"abstract":"This paper reports on lifetime studies of polysilicon and p/sup ++/ Si electrothermal actuators designed for rectilinear displacements. Measurements show that degradation patterns for displacement amplitude can be linked to design variables and operating conditions. At low power levels (which result in average operating temperatures of 300-400/spl deg/C), both types of devices provide continuous DC actuation for >1400 min. and pulse actuation for >30 million cycles without change in amplitude. A model similar to that used for fatigue in steel is used to fit pulse test data for p/sup ++/ Si actuators. The model parameters are explored as functions of operating conditions and device geometry.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125150377","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906583
P. Caton, R. White
This paper reports the design, fabrication, and testing of a new MEMS microfilter developed from a flexural plate wave (FPW) device in which acoustic forces generated within the filter membrane act to free particles and sweep them away from clogged pores. MEMS devices have already been shown to be effective for absolute filtration, but clogging has made them impractical for most applications. Also previously shown was the ability of flexural plate wave (FPW) devices to move particles in a pumped liquid. Recognizing the FPW pumping as a self-cleaning mechanism for microfilters presents exciting possibilities for reduced filter fouling, allowing larger volumes of fluid to be filtered and extending filter lifetime. Both the filtered fluid and the collected large particles could be the useful output. Acoustic particle manipulation has now been shown to free 2 and 10 /spl mu/m diameter spheres and sweep them away from once-blocked pores in both 4 /spl mu/m and 8 /spl mu/m filters. Experiments were performed with deionized (DI) water and polystyrene spheres.
{"title":"MEMS microfilter with acoustic cleaning","authors":"P. Caton, R. White","doi":"10.1109/MEMSYS.2001.906583","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906583","url":null,"abstract":"This paper reports the design, fabrication, and testing of a new MEMS microfilter developed from a flexural plate wave (FPW) device in which acoustic forces generated within the filter membrane act to free particles and sweep them away from clogged pores. MEMS devices have already been shown to be effective for absolute filtration, but clogging has made them impractical for most applications. Also previously shown was the ability of flexural plate wave (FPW) devices to move particles in a pumped liquid. Recognizing the FPW pumping as a self-cleaning mechanism for microfilters presents exciting possibilities for reduced filter fouling, allowing larger volumes of fluid to be filtered and extending filter lifetime. Both the filtered fluid and the collected large particles could be the useful output. Acoustic particle manipulation has now been shown to free 2 and 10 /spl mu/m diameter spheres and sweep them away from once-blocked pores in both 4 /spl mu/m and 8 /spl mu/m filters. Experiments were performed with deionized (DI) water and polystyrene spheres.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122352699","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906543
K. Hoshino, I. Shimoyama
We propose a pneumatically actuated microlens array on a transparent and elastic thin film made of cured PDMS (polydimethylsiloxane). The lenses are 120 /spl square/m in diameter and are arranged on the top surface of 200 /spl square/m-thick base film. The lenses can be moved by pneumatic actuators implemented in the bottom side of the film. Since the lens array and the base film are made of an elastic material PDMS this array could be applied to the surfaces of curved or flexible devices. Properties of PDMS as a material for optical elements, are investigated through the evaluation of the system. We also propose a simulation technique to analyze mechanical and optical properties of deformable optical elements by combining finite element method and ray tracing technique. The optical properties of the fabricated lens array were analyzed using the simulator. This research is a first approach to construct a thin and elastic scanning lens array which can be applied for sensing or imaging applications.
{"title":"An elastic thin-film microlens array with a pneumatic actuator","authors":"K. Hoshino, I. Shimoyama","doi":"10.1109/MEMSYS.2001.906543","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906543","url":null,"abstract":"We propose a pneumatically actuated microlens array on a transparent and elastic thin film made of cured PDMS (polydimethylsiloxane). The lenses are 120 /spl square/m in diameter and are arranged on the top surface of 200 /spl square/m-thick base film. The lenses can be moved by pneumatic actuators implemented in the bottom side of the film. Since the lens array and the base film are made of an elastic material PDMS this array could be applied to the surfaces of curved or flexible devices. Properties of PDMS as a material for optical elements, are investigated through the evaluation of the system. We also propose a simulation technique to analyze mechanical and optical properties of deformable optical elements by combining finite element method and ray tracing technique. The optical properties of the fabricated lens array were analyzed using the simulator. This research is a first approach to construct a thin and elastic scanning lens array which can be applied for sensing or imaging applications.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116830819","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906538
H. Miyashita, T. Ono, P. N. Minh, M. Esashi
In this paper, we present the growth techniques of carbon nanotubes and its application for nano-electromechanical devices. Several methods were attempted for the selective growth of the carbon nanotubes. Catalyzed metal (Ni) patterning and the following hot-filament chemical vapor deposition enable to grow carbon nanotubes on the metal pattern formed on quartz glass. However, no carbon nanotubes are grown on a flat silicon substrate using this method. It is found that the high electrostatic field with a negative substrate bias enhances the growth of the carbon nanotubes. This growth enhancement effect is applied to fabricate single carbon nanotube tip on silicon for scanning probe microscopy.
{"title":"Selective growth of carbon nanotubes for nano electro mechanical device","authors":"H. Miyashita, T. Ono, P. N. Minh, M. Esashi","doi":"10.1109/MEMSYS.2001.906538","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906538","url":null,"abstract":"In this paper, we present the growth techniques of carbon nanotubes and its application for nano-electromechanical devices. Several methods were attempted for the selective growth of the carbon nanotubes. Catalyzed metal (Ni) patterning and the following hot-filament chemical vapor deposition enable to grow carbon nanotubes on the metal pattern formed on quartz glass. However, no carbon nanotubes are grown on a flat silicon substrate using this method. It is found that the high electrostatic field with a negative substrate bias enhances the growth of the carbon nanotubes. This growth enhancement effect is applied to fabricate single carbon nanotube tip on silicon for scanning probe microscopy.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128420118","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 : 2001-01-21DOI: 10.1007/978-3-642-56763-6_20
Yi-Kuen Lee, J. Deval, Patrick Tabeling, Chih-Ming Ho
{"title":"Chaotic mixing in electrokinetically and pressure driven micro flows","authors":"Yi-Kuen Lee, J. Deval, Patrick Tabeling, Chih-Ming Ho","doi":"10.1007/978-3-642-56763-6_20","DOIUrl":"https://doi.org/10.1007/978-3-642-56763-6_20","url":null,"abstract":"","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129029987","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906502
Salim Bouaidat, Gert Friis Eriksen, R. D. Reus, P. E. Andersen, Siebe Bouwstra
A new piezoresistive differential pressure sensor design for harsh wet environments is presented. The sensor design is based on a deposited membrane, which is deposited on top of polysilicon interconnects and piezoresistors. Flat membrane surfaces are thereby achieved. This enables thin film protective coating using sputtered films, which usually have poor step coverage. The concept is demonstrated using both epipoly silicon and sputtered amorphous silicon as membrane materials and tantalum oxide as coating material. Using polysilicon piezoresistors, a sensitivity of 11.3 mV/V bar was obtained. Exposure of the sensors with sputtered amorphous silicon membranes to aggressive media with pH 11 and 70/spl deg/C for 20 hours did not change their performance.
{"title":"Aggressive media exposed differential pressure sensor with a deposited membrane","authors":"Salim Bouaidat, Gert Friis Eriksen, R. D. Reus, P. E. Andersen, Siebe Bouwstra","doi":"10.1109/MEMSYS.2001.906502","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906502","url":null,"abstract":"A new piezoresistive differential pressure sensor design for harsh wet environments is presented. The sensor design is based on a deposited membrane, which is deposited on top of polysilicon interconnects and piezoresistors. Flat membrane surfaces are thereby achieved. This enables thin film protective coating using sputtered films, which usually have poor step coverage. The concept is demonstrated using both epipoly silicon and sputtered amorphous silicon as membrane materials and tantalum oxide as coating material. Using polysilicon piezoresistors, a sensitivity of 11.3 mV/V bar was obtained. Exposure of the sensors with sputtered amorphous silicon membranes to aggressive media with pH 11 and 70/spl deg/C for 20 hours did not change their performance.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"121 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129101199","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 : 2001-01-21DOI: 10.1109/MEMSYS.2001.906515
N. Svedin, E. Stemme, Göran Stemme
A new class of flow sensors is introduced where a static turbine converts the volume flow into a torque. In contrast to conventional turbine meters, the wheel does not rotate and consequently it is not sensitive to bearing friction and wear that a rotating wheel experiences. The sensor performance has been evaluated for different blade lengths and blade angles and a model is given to predict the influence of these parameters. Optimization of the wheel can be done in terms of maximizing the sensitivity/pressure-loss ratio. The most efficient wheel in this analysis has a blade length of 2.7 mm and a blade angle of 30/spl deg/ giving a sensitivity of 4.0 /spl mu/V/V/(1/min) when measured using a new silicon torque sensor design.
{"title":"A static turbine flow meter with a micromachined silicon torque sensor","authors":"N. Svedin, E. Stemme, Göran Stemme","doi":"10.1109/MEMSYS.2001.906515","DOIUrl":"https://doi.org/10.1109/MEMSYS.2001.906515","url":null,"abstract":"A new class of flow sensors is introduced where a static turbine converts the volume flow into a torque. In contrast to conventional turbine meters, the wheel does not rotate and consequently it is not sensitive to bearing friction and wear that a rotating wheel experiences. The sensor performance has been evaluated for different blade lengths and blade angles and a model is given to predict the influence of these parameters. Optimization of the wheel can be done in terms of maximizing the sensitivity/pressure-loss ratio. The most efficient wheel in this analysis has a blade length of 2.7 mm and a blade angle of 30/spl deg/ giving a sensitivity of 4.0 /spl mu/V/V/(1/min) when measured using a new silicon torque sensor design.","PeriodicalId":311365,"journal":{"name":"Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123405388","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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