Pub Date : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056338
V. Zega, A. Opreni, G. Mussi, Hyun-Keun Kwon, G. Vukasin, G. Gattere, G. Langfelder, A. Frangi, T. Kenny
The design, fabrication and experimental validation of two MicroElectroMechanical Systems (MEMS) Double-Ended Tuning-Fork (DETF) resonators that exhibit an intrinsic sub-350 ppm thermal stability in the temperature range [5°C–85°C] are reported. A strategy for the optimization of the design of MEMS resonators that exhibit high thermal stability and high quality factor is also provided and a good agreement with experimental data is achieved. The main advantage of the proposed strategy is that it does not require any experimental calibration of the model parameters and can be in principle applied to different kind of resonators, thus representing a powerful tool for the apriori design of thermally stable MEMS resonators with high quality factors.
{"title":"Thermal Stability of DETF MEMS Resonators: Numerical Modelling and Experimental Validation","authors":"V. Zega, A. Opreni, G. Mussi, Hyun-Keun Kwon, G. Vukasin, G. Gattere, G. Langfelder, A. Frangi, T. Kenny","doi":"10.1109/MEMS46641.2020.9056338","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056338","url":null,"abstract":"The design, fabrication and experimental validation of two MicroElectroMechanical Systems (MEMS) Double-Ended Tuning-Fork (DETF) resonators that exhibit an intrinsic sub-350 ppm thermal stability in the temperature range [5°C–85°C] are reported. A strategy for the optimization of the design of MEMS resonators that exhibit high thermal stability and high quality factor is also provided and a good agreement with experimental data is achieved. The main advantage of the proposed strategy is that it does not require any experimental calibration of the model parameters and can be in principle applied to different kind of resonators, thus representing a powerful tool for the apriori design of thermally stable MEMS resonators with high quality factors.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"20 1","pages":"1207-1210"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81968246","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056287
Pietro Simeoni, Matteo Castellani, G. Piazza
We report on the first implementation of a long-range wake-up receiver (WuRx) enabled by an aggressively scaled 100 nm thick aluminum nitride transducer that occupies an area of only $100 mu mathrm{m} times 100 mu mathrm{m}$. This piezoelectric Nanoscale Ultrasound Transducer (pNUT) offers the same sensitivity and characteristic impedance of its microscale counterparts but enables “dust-like” WuRx because of its dramatically reduced size. We validate this concept by synthesizing a WuRx using a pNUT and off-the-shelf electronic components forming a voltage amplifier, an envelope detector and a comparator (Fig. 1). We demonstrate robust data transfer over a range of 0.5 m when operating with a 40 kHz carrier signal modulated at 250Hz. Based on these measurements we extrapolate the device performance at resonance to show that communication over> 10m is possible without increasing the WuRx area.
我们报告了远程唤醒接收器(WuRx)的第一个实现，该接收器由一个积极缩放的100纳米厚氮化铝传感器实现，该传感器仅占用$100 mu mathm {m} 乘以 100 mu mathm {m}$的面积。这种压电纳米级超声换能器(pNUT)提供了与微级同类产品相同的灵敏度和特性阻抗，但由于其尺寸显着减小，因此可以实现“粉尘状”的WuRx。我们通过使用pNUT和现成的电子元件合成WuRx来验证这一概念，这些电子元件组成了电压放大器、包络检测器和比较器(图1)。我们展示了在以250Hz调制的40 kHz载波信号下工作时，在0.5 m范围内的稳健数据传输。根据这些测量结果，我们推断出设备在共振时的性能，表明在不增加WuRx面积的情况下，通信超过10米是可能的。
{"title":"Long-Rangeultrasound Wake-Up Receiver with a Piezoelectric Nanoscale Ultrasound Transducer (pNUT)","authors":"Pietro Simeoni, Matteo Castellani, G. Piazza","doi":"10.1109/MEMS46641.2020.9056287","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056287","url":null,"abstract":"We report on the first implementation of a long-range wake-up receiver (WuRx) enabled by an aggressively scaled 100 nm thick aluminum nitride transducer that occupies an area of only $100 mu mathrm{m} times 100 mu mathrm{m}$. This piezoelectric Nanoscale Ultrasound Transducer (pNUT) offers the same sensitivity and characteristic impedance of its microscale counterparts but enables “dust-like” WuRx because of its dramatically reduced size. We validate this concept by synthesizing a WuRx using a pNUT and off-the-shelf electronic components forming a voltage amplifier, an envelope detector and a comparator (Fig. 1). We demonstrate robust data transfer over a range of 0.5 m when operating with a 40 kHz carrier signal modulated at 250Hz. Based on these measurements we extrapolate the device performance at resonance to show that communication over> 10m is possible without increasing the WuRx area.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"1 1","pages":"849-852"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78240346","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056226
S. Jayhooni, B. Assadsangabi, G. Hohert, P. Lane, H. Zeng, K. Takahata
This paper reports, for the first time, a MEMS rotary actuator that enables side-viewing microendoscopic probes with different modalities for luminal tissue analysis. The developed tubular-form micro rotary actuator offers both high-speed and stepping motions that are compatible with the use for optical coherence tomography (OCT) and Raman spectroscopy, respectively. The actuator, improved from its preceding designs, shows up to 125× higher revolution speeds per power while enabling arbitrary angle-resolved stepping rotations in a ∼50% thinner body, with significantly reduced heating effect for biologically safe operation in vivo. Preliminary testing of the OCT endoscopic probe integrated with the developed rotary actuator/scanner successfully demonstrates real-time 360° imaging of live human skin tissue.
{"title":"High-Speed and Stepping MEMS Rotary Actuator for Multimodal, 360° Side-Viewing Endoscopic Probes","authors":"S. Jayhooni, B. Assadsangabi, G. Hohert, P. Lane, H. Zeng, K. Takahata","doi":"10.1109/MEMS46641.2020.9056226","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056226","url":null,"abstract":"This paper reports, for the first time, a MEMS rotary actuator that enables side-viewing microendoscopic probes with different modalities for luminal tissue analysis. The developed tubular-form micro rotary actuator offers both high-speed and stepping motions that are compatible with the use for optical coherence tomography (OCT) and Raman spectroscopy, respectively. The actuator, improved from its preceding designs, shows up to 125× higher revolution speeds per power while enabling arbitrary angle-resolved stepping rotations in a ∼50% thinner body, with significantly reduced heating effect for biologically safe operation in vivo. Preliminary testing of the OCT endoscopic probe integrated with the developed rotary actuator/scanner successfully demonstrates real-time 360° imaging of live human skin tissue.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"75 1","pages":"376-379"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78650549","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056113
M. Kumemura, L. Kudo, Zhongcai Ma, S. Karsten
We developed a MEMS based sensor, Nanopin, for mechanical characterization of individual adherent cells. Nanopin consists of sensing tip that forms a contact with a cell, a displacement sensor, and an actuator. The feasibility of sensing was evaluated using various concentrations of agarose gel, and then the stiffness measurements of human carcinoma cells were conducted on different surfaces. After the measurements of cells, we confirmed that cells grow normally in an incubator.
{"title":"Nanopin - A MEMS Based Sensor for the Analysis of Single Cell Mechanical Properties","authors":"M. Kumemura, L. Kudo, Zhongcai Ma, S. Karsten","doi":"10.1109/MEMS46641.2020.9056113","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056113","url":null,"abstract":"We developed a MEMS based sensor, Nanopin, for mechanical characterization of individual adherent cells. Nanopin consists of sensing tip that forms a contact with a cell, a displacement sensor, and an actuator. The feasibility of sensing was evaluated using various concentrations of agarose gel, and then the stiffness measurements of human carcinoma cells were conducted on different surfaces. After the measurements of cells, we confirmed that cells grow normally in an incubator.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"1 1","pages":"311-314"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75455890","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056317
R. Gando, D. Ono, S. Kaji, H. Ota, T. Itakura, Y. Tomizawa
This paper presents the first microcontroller-based module-level MEMS rate integrating gyroscope (RIG) for direct angle measurement after automatic asymmetry calibration. The 5-cm prototype module integrates a vacuum-sealed donut-mass gyroscope device on analog and digital PCBs. In automatic calibration mode, the initial frequency and decay-time asymmetries are electrically tuned and reduced by >40 and >18 times, respectively. The sensing mode is enabled by built-in digital controls of vibration energy and frequency. Continuous angle measurement is confirmed with an angular random walk (ARW) of 0.6 deg/rt-h and a bias instability (BI) of 4.3 deg/h, proving comparable performances with previous FPGA-based large RIG systems. This module paves the way for RIG commercialization studies.
{"title":"A Compact Microcontroller-Based MEMS Rate Integrating Gyroscope Module with Automatic Asymmetry Calibration","authors":"R. Gando, D. Ono, S. Kaji, H. Ota, T. Itakura, Y. Tomizawa","doi":"10.1109/MEMS46641.2020.9056317","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056317","url":null,"abstract":"This paper presents the first microcontroller-based module-level MEMS rate integrating gyroscope (RIG) for direct angle measurement after automatic asymmetry calibration. The 5-cm prototype module integrates a vacuum-sealed donut-mass gyroscope device on analog and digital PCBs. In automatic calibration mode, the initial frequency and decay-time asymmetries are electrically tuned and reduced by >40 and >18 times, respectively. The sensing mode is enabled by built-in digital controls of vibration energy and frequency. Continuous angle measurement is confirmed with an angular random walk (ARW) of 0.6 deg/rt-h and a bias instability (BI) of 4.3 deg/h, proving comparable performances with previous FPGA-based large RIG systems. This module paves the way for RIG commercialization studies.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"10 1","pages":"1296-1299"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72602014","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056265
M. Bestetti, V. Zega, G. Langfelder
The work presents a detailed modeling and the first-ever characterization of a frequency modulated (FM) yaw gyroscope in presence of vibrations from low frequency (30 Hz), through the main modes, and up to 40 kHz. The gyroscope two in-plane axes (around 25 kHz) are operated under a Lissajous trajectory (70 Hz period) by an integrated circuit (IC) including oscillators, frequency digitization, and digital demodulation stages. In presence of $2-g_{pk-pk}$ vibrations, no effects are visible across the spectrum apart from the region including the modes. In this range, as predicted by theory, for each axis no effect is observed for accelerations at the axis resonance (< 0.1 dps/g), but a huge effect (tens of dps/g) is visible for accelerations at an offset frequency from resonance corresponding to the mode split.
{"title":"Modeling and First Characterization of Broad-Spectrum Vibration Rejection of Frequency Modulated Gyroscopes","authors":"M. Bestetti, V. Zega, G. Langfelder","doi":"10.1109/MEMS46641.2020.9056265","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056265","url":null,"abstract":"The work presents a detailed modeling and the first-ever characterization of a frequency modulated (FM) yaw gyroscope in presence of vibrations from low frequency (30 Hz), through the main modes, and up to 40 kHz. The gyroscope two in-plane axes (around 25 kHz) are operated under a Lissajous trajectory (70 Hz period) by an integrated circuit (IC) including oscillators, frequency digitization, and digital demodulation stages. In presence of $2-g_{pk-pk}$ vibrations, no effects are visible across the spectrum apart from the region including the modes. In this range, as predicted by theory, for each axis no effect is observed for accelerations at the axis resonance (< 0.1 dps/g), but a huge effect (tens of dps/g) is visible for accelerations at an offset frequency from resonance corresponding to the mode split.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"23 1","pages":"259-262"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75072469","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056115
Tobias Weber, C. Zgierski-Johnston, Eric Klein, S. Ayub, P. Kohl, O. Paul, P. Ruther
This paper reports on the fabrication, assembly, characterization and validation of a novel opto-electrical cardiac stimulator designed to augment a mechanical pacing device. The integration of miniaturized electrodes and blue light-emitting diode (LED) chips on the pacer tip with a diameter of 1 mm enables the application of multimodal stimuli in one location on the surface of isolated murine hearts. The opto-electrical stimulator is based on two separate polyimide (PI) substrates each with a thickness of $10 mu mathrm{m}$ combined into a functional unit based on dedicated assembly and encapsulation processes using silicone rubber. The experimental validation in isolated, whole hearts compares electrical, optical and mechanical stimuli exerted at frequencies of up to 8 Hz on Langen-dorff-perfused hearts expressing channelrhodopsin-2. The integrated iridium oxide electrodes implemented above the LED chips enable simultaneous electrical recordings of local cardiac electrical activity.
本文报道了一种新型光电心脏刺激器的制造、组装、表征和验证，该装置旨在增强机械起搏装置。微型电极和直径为1毫米的蓝色发光二极管(LED)芯片集成在起搏器尖端，可以在孤立的小鼠心脏表面的一个位置应用多模态刺激。光电刺激器基于两个独立的聚酰亚胺(PI)衬底，每个衬底的厚度为$10 mu mathm {m}$，结合成一个基于专用组装和使用硅橡胶封装工艺的功能单元。在分离的全心脏中进行的实验验证比较了以高达8赫兹的频率施加在表达通道视紫红质-2的兰根-多尔夫灌注心脏上的电、光和机械刺激。集成的氧化铱电极实现在LED芯片之上，可以同时记录局部心脏电活动。
{"title":"Concentric, Mems-Based Optoelectromechanical Pacer for Multimodal Cardiac Excitation","authors":"Tobias Weber, C. Zgierski-Johnston, Eric Klein, S. Ayub, P. Kohl, O. Paul, P. Ruther","doi":"10.1109/MEMS46641.2020.9056115","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056115","url":null,"abstract":"This paper reports on the fabrication, assembly, characterization and validation of a novel opto-electrical cardiac stimulator designed to augment a mechanical pacing device. The integration of miniaturized electrodes and blue light-emitting diode (LED) chips on the pacer tip with a diameter of 1 mm enables the application of multimodal stimuli in one location on the surface of isolated murine hearts. The opto-electrical stimulator is based on two separate polyimide (PI) substrates each with a thickness of $10 mu mathrm{m}$ combined into a functional unit based on dedicated assembly and encapsulation processes using silicone rubber. The experimental validation in isolated, whole hearts compares electrical, optical and mechanical stimuli exerted at frequencies of up to 8 Hz on Langen-dorff-perfused hearts expressing channelrhodopsin-2. The integrated iridium oxide electrodes implemented above the LED chips enable simultaneous electrical recordings of local cardiac electrical activity.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"6 1","pages":"361-364"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80162608","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056413
Yang Bu, Yue Jiang, Saeko Kawano, B. S. T. Tam, Sheng Ni, Liying Lin, O. Tabata, T. Tsuchiya, X. Wang, M. Wong
A micro-fabricated planar bi-stable mechanical latch is demonstrated and presently reported. The compact size of the bi-stable mechanism is achieved by enclosing an anchored latch groove in the center of other movable structures. Driven using a single actuator, the device can be switched mechanically between two stable states by applying respective setting and resetting voltage of 10.3 V and 9.5 V. Exhibiting good durability and promising potential for applications demanding micro-switches, the device was demonstrated as an electrical switch to control a light-emitting diode.
{"title":"A Planar Single-Actuator Bi-Stable Mechanical Latch as an Electrical Switch","authors":"Yang Bu, Yue Jiang, Saeko Kawano, B. S. T. Tam, Sheng Ni, Liying Lin, O. Tabata, T. Tsuchiya, X. Wang, M. Wong","doi":"10.1109/MEMS46641.2020.9056413","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056413","url":null,"abstract":"A micro-fabricated planar bi-stable mechanical latch is demonstrated and presently reported. The compact size of the bi-stable mechanism is achieved by enclosing an anchored latch groove in the center of other movable structures. Driven using a single actuator, the device can be switched mechanically between two stable states by applying respective setting and resetting voltage of 10.3 V and 9.5 V. Exhibiting good durability and promising potential for applications demanding micro-switches, the device was demonstrated as an electrical switch to control a light-emitting diode.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"42 1","pages":"493-496"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91221825","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 : 2020-01-01DOI: 10.1109/MEMS46641.2020.9056168
Byunggeon Park, Young Jung, M. Shin, J. Ko, Hanchul Cho
Shape memory polymer (SMP) is a polymer based on PU that has the property of restoring to its original shape at a specific temperature like a shape memory alloy. This ability could improve durability of sensors in cyclic loading. We fabricate a porous structured sensor having a self-recovery ability. This sensor shows good durability and sensitivity than other polyurethane porous structure. Also, the developed sensor is rapidly restored in 30 seconds in a 70 °C oven. We propose a self-recovering capacitive pressure sensor which has excellent durability. Furthermore, it works in the wide pressure range (∼400kPa) with good linearity.
{"title":"Self-Recovering 3-Dimensional Micro Pore Structure Pressure Sensor Using Shape Memory Polymer","authors":"Byunggeon Park, Young Jung, M. Shin, J. Ko, Hanchul Cho","doi":"10.1109/MEMS46641.2020.9056168","DOIUrl":"https://doi.org/10.1109/MEMS46641.2020.9056168","url":null,"abstract":"Shape memory polymer (SMP) is a polymer based on PU that has the property of restoring to its original shape at a specific temperature like a shape memory alloy. This ability could improve durability of sensors in cyclic loading. We fabricate a porous structured sensor having a self-recovery ability. This sensor shows good durability and sensitivity than other polyurethane porous structure. Also, the developed sensor is rapidly restored in 30 seconds in a 70 °C oven. We propose a self-recovering capacitive pressure sensor which has excellent durability. Furthermore, it works in the wide pressure range (∼400kPa) with good linearity.","PeriodicalId":6776,"journal":{"name":"2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS)","volume":"71 1","pages":"685-688"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91227717","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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