Pub Date : 2013-10-01DOI: 10.1109/SIITME.2013.6743658
Diana Maria Bucur, N. Militaru, G. Lojewski
Considering loss effects on signals in the design of a circuit or a system that works at high frequency will allow to accurately predict a realistic behavior through models that include specific parameters. Losses in dielectric materials and in conductors are simulated in time or frequency domains where different models can better estimate the materials' properties. In the present paper we apply and compare dielectric models like single, multi-pole and wideband Debye models that are used to estimate frequency dependent properties of dielectric losses in high speed applications. A variant of frequency-dependent finite difference time domain (FD2TD) will be applied to properly describe the electromagnetic field in space and time, in a recursive mode for easy implementation.
{"title":"Models of dielectric materials used in high-speed design by FD2TD method","authors":"Diana Maria Bucur, N. Militaru, G. Lojewski","doi":"10.1109/SIITME.2013.6743658","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743658","url":null,"abstract":"Considering loss effects on signals in the design of a circuit or a system that works at high frequency will allow to accurately predict a realistic behavior through models that include specific parameters. Losses in dielectric materials and in conductors are simulated in time or frequency domains where different models can better estimate the materials' properties. In the present paper we apply and compare dielectric models like single, multi-pole and wideband Debye models that are used to estimate frequency dependent properties of dielectric losses in high speed applications. A variant of frequency-dependent finite difference time domain (FD2TD) will be applied to properly describe the electromagnetic field in space and time, in a recursive mode for easy implementation.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121340291","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743667
A. Oros, Ingrid Kovacs, M. Topa, Andi Buzo, M. Rafaila, Manuel Harrant, G. Pelz
The paper focuses on treating and characterizing variations that occur in measurements or that are intrinsic in electronic systems. Methods illustrating basic principles of Design of Experiments such as replication and blocking are implemented and used so that valid and objective conclusions are drawn. Replication is used for three purposes: verifying the metamodel adequacy, defining the confidence interval of the measured mean value of the system's response and determining the minimum number of replications that are needed in order to measure the system's response with a given accuracy. Blocking helps with eliminating the systematic error that appears due to the measuring conditions and was used in the screening process. The methods were applied on a lighting control system used in automotive applications.
{"title":"Data improvement in lab verification of smart power products using DoE","authors":"A. Oros, Ingrid Kovacs, M. Topa, Andi Buzo, M. Rafaila, Manuel Harrant, G. Pelz","doi":"10.1109/SIITME.2013.6743667","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743667","url":null,"abstract":"The paper focuses on treating and characterizing variations that occur in measurements or that are intrinsic in electronic systems. Methods illustrating basic principles of Design of Experiments such as replication and blocking are implemented and used so that valid and objective conclusions are drawn. Replication is used for three purposes: verifying the metamodel adequacy, defining the confidence interval of the measured mean value of the system's response and determining the minimum number of replications that are needed in order to measure the system's response with a given accuracy. Blocking helps with eliminating the systematic error that appears due to the measuring conditions and was used in the screening process. The methods were applied on a lighting control system used in automotive applications.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114670897","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743688
B. Medgyes, B. Illés, D. Rigler, M. Ruszinkó, L. Gál
Electrochemical migration (ECM) behaviour investigations were carried out on “oxide-free” and highly oxidized copper surfaces in pure water. It was shown in our previous paper that the oxidation number of copper ion mainly depends on the oxide layer thickness of the copper surface; in the case of “oxide-free” copper surface the Cu1+ ions dominated, while Cu2+ ions were mainly formed in the case of highly oxidized copper surface, which modify the standard electrode potential and also the solubility product constant of copper-hydroxides, thus can effect on the mean time to failure (MTTF) caused by ECM. In order to verify the effect of different copper ions (Cu1+ vs. Cu2+) on MTTF, water drop (WD) tests were carried out on both copper surfaces. The results showed that in the case of “oxide-free” copper the MTTF value was lower than in the case of highly oxidized copper.
{"title":"Electrochemical migration of copper in pure water used in printed circuit boards","authors":"B. Medgyes, B. Illés, D. Rigler, M. Ruszinkó, L. Gál","doi":"10.1109/SIITME.2013.6743688","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743688","url":null,"abstract":"Electrochemical migration (ECM) behaviour investigations were carried out on “oxide-free” and highly oxidized copper surfaces in pure water. It was shown in our previous paper that the oxidation number of copper ion mainly depends on the oxide layer thickness of the copper surface; in the case of “oxide-free” copper surface the Cu1+ ions dominated, while Cu2+ ions were mainly formed in the case of highly oxidized copper surface, which modify the standard electrode potential and also the solubility product constant of copper-hydroxides, thus can effect on the mean time to failure (MTTF) caused by ECM. In order to verify the effect of different copper ions (Cu1+ vs. Cu2+) on MTTF, water drop (WD) tests were carried out on both copper surfaces. The results showed that in the case of “oxide-free” copper the MTTF value was lower than in the case of highly oxidized copper.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132220782","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743682
A. Vasile, C. Marghescu
Two very important and seemingly unrelated problems are the following: providing a reliable energy source for computers and finding solutions to store energy from renewable sources. It is necessary to find solutions with high energy storage efficiency in case of malfunctions of the 230 V electricity network that supplies computers as well as systems to store the energy generated from solar energy conversion systems or systems with regenerative braking on vehicles [1]. Accumulators store charge for long periods of time under constant voltage and relatively small currents, but they can supply very high currents. One possible solution is the use of a system based on an EDLC and a battery. Important characteristics of EDLC (Electric Double-Layer Capacitors of Supercapacitors) are the charging current and the supply current that can reach values of up to 1000 A and 100000 charging/discharging cycles. The configuration that was researched can accumulate and generate electric charge under currents of tens of amperes. The advantages of using this battery-EDLC tandem in UPS units consist of reducing the specific weight of the equipment and increasing the lifespan of the UPS unit with up to 10 years. Another advantage of using this system is given by the larger number of charge/discharge cycles possible through the use of supercapacitors and eliminating the electric switching systems.
{"title":"EDLC hybrid system with increased lifespan for supplying an UPS","authors":"A. Vasile, C. Marghescu","doi":"10.1109/SIITME.2013.6743682","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743682","url":null,"abstract":"Two very important and seemingly unrelated problems are the following: providing a reliable energy source for computers and finding solutions to store energy from renewable sources. It is necessary to find solutions with high energy storage efficiency in case of malfunctions of the 230 V electricity network that supplies computers as well as systems to store the energy generated from solar energy conversion systems or systems with regenerative braking on vehicles [1]. Accumulators store charge for long periods of time under constant voltage and relatively small currents, but they can supply very high currents. One possible solution is the use of a system based on an EDLC and a battery. Important characteristics of EDLC (Electric Double-Layer Capacitors of Supercapacitors) are the charging current and the supply current that can reach values of up to 1000 A and 100000 charging/discharging cycles. The configuration that was researched can accumulate and generate electric charge under currents of tens of amperes. The advantages of using this battery-EDLC tandem in UPS units consist of reducing the specific weight of the equipment and increasing the lifespan of the UPS unit with up to 10 years. Another advantage of using this system is given by the larger number of charge/discharge cycles possible through the use of supercapacitors and eliminating the electric switching systems.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123450979","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743652
A. Hapenciuc, P. Svasta
Slow scan television (SSTV) image transmission system is used by many decades by radio amateurs. There are numerous modes, some for B/W others for color images. We choose the Robot36 mode because it is transmitting color images and because is widely used. Usually this requires a PC to capture and process the data to get the audio signal necessary for transmission. In recent years the development of low cost embedded platforms open the possibility to replace the large PC with a small ARM boards to do all the video capture and single processing. In this case we used on of the cheapest model: Raspberry PI. For signal modulation and radio transmission, a miniature solution was developed using parts commercially available. The transmitter runs on 433.8MHz, output power 1.5W, and uses narrow band FM modulation, as the SSTV standard requires. Because of the small size relative to dissipate power, heat dissipation was carefully investigated. On the image was overlaid the data taken from GPS as an “on screen display” (OSD).
{"title":"Long range image radio transmitter","authors":"A. Hapenciuc, P. Svasta","doi":"10.1109/SIITME.2013.6743652","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743652","url":null,"abstract":"Slow scan television (SSTV) image transmission system is used by many decades by radio amateurs. There are numerous modes, some for B/W others for color images. We choose the Robot36 mode because it is transmitting color images and because is widely used. Usually this requires a PC to capture and process the data to get the audio signal necessary for transmission. In recent years the development of low cost embedded platforms open the possibility to replace the large PC with a small ARM boards to do all the video capture and single processing. In this case we used on of the cheapest model: Raspberry PI. For signal modulation and radio transmission, a miniature solution was developed using parts commercially available. The transmitter runs on 433.8MHz, output power 1.5W, and uses narrow band FM modulation, as the SSTV standard requires. Because of the small size relative to dissipate power, heat dissipation was carefully investigated. On the image was overlaid the data taken from GPS as an “on screen display” (OSD).","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127450276","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743677
I. Orha, S. Oniga
In this paper we have proposed to present a system for automatic recording of the main physiological parameters of the human body: body temperature, blood pressure, respiratory rate, electrocardiogram (ECG), skin resistance, etc. To realize this system, we have developed a program that can read and automatically save in a file, the data from specialized sensors. Further it is possible to interpret of the results, by comparing them with known normal values and thus offering the possibility for a primary health status diagnosis by specialized personnel. The data received from the sensors is taken by an interface circuit, provided with signal conditioning (filtering, amplification, etc). Data acquisition is controlled by a microcontroller using an Arduino Uno standard development platform. The data are transferred to a PC, using serial communication port of Arduino platform. The whole process of health assessment is commissioned by a new program developed by us in the Python programming language. The program provides automatic recording of the aforementioned parameters in a predetermined sequence, or if you want only certain parameters are registered.
{"title":"Automated system for evaluating health status","authors":"I. Orha, S. Oniga","doi":"10.1109/SIITME.2013.6743677","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743677","url":null,"abstract":"In this paper we have proposed to present a system for automatic recording of the main physiological parameters of the human body: body temperature, blood pressure, respiratory rate, electrocardiogram (ECG), skin resistance, etc. To realize this system, we have developed a program that can read and automatically save in a file, the data from specialized sensors. Further it is possible to interpret of the results, by comparing them with known normal values and thus offering the possibility for a primary health status diagnosis by specialized personnel. The data received from the sensors is taken by an interface circuit, provided with signal conditioning (filtering, amplification, etc). Data acquisition is controlled by a microcontroller using an Arduino Uno standard development platform. The data are transferred to a PC, using serial communication port of Arduino platform. The whole process of health assessment is commissioned by a new program developed by us in the Python programming language. The program provides automatic recording of the aforementioned parameters in a predetermined sequence, or if you want only certain parameters are registered.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"18 2_suppl 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128979871","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743668
C. Pitu, R. Câmpeanu
This paper presents differences and similarities between experimental and simulated differential power analysis (DPA) based security attacks. DPA attacks are known for many years and experimental attacks have been performed on a large number of hardware and/or software implementations of various cryptographic algorithms (RSA, AES, etc.). Vulnerabilities are mostly discovered after the product has been released to the market making it quasi impossible to fix them. Therefore, a new approach to detecting security vulnerabilities is needed; one that detects flaws early in the design process, before the circuit is manufactured. This method relies on digital simulations rather than on experimental measurements. Simulations are the foundation of functional verification of digital circuits. Using a specifically for this purpose developed software framework, called Power Analysis Toolkit, a comparison between simulated and experimental DPA attacks was performed. The attacked circuit is a hardware implementation of the well-known AES cryptographic algorithm. Results show that, using the correct assumptions, digital simulations can be used to uncover security vulnerabilities.
{"title":"Differential power analysis: Simulated versus experimental attacks","authors":"C. Pitu, R. Câmpeanu","doi":"10.1109/SIITME.2013.6743668","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743668","url":null,"abstract":"This paper presents differences and similarities between experimental and simulated differential power analysis (DPA) based security attacks. DPA attacks are known for many years and experimental attacks have been performed on a large number of hardware and/or software implementations of various cryptographic algorithms (RSA, AES, etc.). Vulnerabilities are mostly discovered after the product has been released to the market making it quasi impossible to fix them. Therefore, a new approach to detecting security vulnerabilities is needed; one that detects flaws early in the design process, before the circuit is manufactured. This method relies on digital simulations rather than on experimental measurements. Simulations are the foundation of functional verification of digital circuits. Using a specifically for this purpose developed software framework, called Power Analysis Toolkit, a comparison between simulated and experimental DPA attacks was performed. The attacked circuit is a hardware implementation of the well-known AES cryptographic algorithm. Results show that, using the correct assumptions, digital simulations can be used to uncover security vulnerabilities.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114279961","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743663
R. Joian, D. Petreus, R. Etz, C. Lung
The project aims the implementation of an hydro-wind hybrid system. The advantages of this are clear: to supply the electricity in the isolated houses or group houses with limited power consumption, an alternative to the connection at the National Power Grid, especially where this is not possible. The proposed hybrid model includes a physical wind subsystem that links physical model hydro subsystem to form the physical model of hydro-wind hybrid system.
{"title":"The experimental stand for the study of the hydro wind hybrid power stations","authors":"R. Joian, D. Petreus, R. Etz, C. Lung","doi":"10.1109/SIITME.2013.6743663","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743663","url":null,"abstract":"The project aims the implementation of an hydro-wind hybrid system. The advantages of this are clear: to supply the electricity in the isolated houses or group houses with limited power consumption, an alternative to the connection at the National Power Grid, especially where this is not possible. The proposed hybrid model includes a physical wind subsystem that links physical model hydro subsystem to form the physical model of hydro-wind hybrid system.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127864943","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743649
R. Bozomitu, N. Cojan, G. Bonteanu
In this paper a VLSI implementation of the 4th order elliptic fully differential IIR switched-capacitor low-pass filter in CMOS technology is presented. The proposed LPF is composed of two switched-capacitor biquad filter structures connected in cascade. Its transfer function is determined by computing the discrete Fourier transform of the impulse response function. The circuit is implemented on the basis of some building blocks such as operational transconductance amplifiers, transmission gate switches, capacitors and non-overlapping clocks generator. The simulations performed in 180nm CMOS technology confirm the theoretical results.
{"title":"A VLSI implementation of the 4th order elliptic fully differential IIR switched-capacitor low-pass filter in CMOS technology","authors":"R. Bozomitu, N. Cojan, G. Bonteanu","doi":"10.1109/SIITME.2013.6743649","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743649","url":null,"abstract":"In this paper a VLSI implementation of the 4th order elliptic fully differential IIR switched-capacitor low-pass filter in CMOS technology is presented. The proposed LPF is composed of two switched-capacitor biquad filter structures connected in cascade. Its transfer function is determined by computing the discrete Fourier transform of the impulse response function. The circuit is implemented on the basis of some building blocks such as operational transconductance amplifiers, transmission gate switches, capacitors and non-overlapping clocks generator. The simulations performed in 180nm CMOS technology confirm the theoretical results.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"606 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116391641","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 : 2013-10-01DOI: 10.1109/SIITME.2013.6743656
D. Vuza, R. Frosch, H. Koeberl, M. Vlădescu
A new RFID reader for the 13.56 MHz carrier frequency was developed in the framework of the collaboration between Freaquent Frosch Electronics (FE) and the first author. The reader is intended to cover the standards ISO/IEC FDIS 18000 [1], ISO/IEC FCD 15693 [2] and to provide long-range reading as well as inventory of large collections of tags. The reader features a class E switching power amplifier in the transmission path and several means for achieving a high quality signal in the reception path. Our paper will be focused on the procedures we developed for processing, storing and decoding the signal received from tags.
{"title":"Aspects of data reception in a high performance RFID reader","authors":"D. Vuza, R. Frosch, H. Koeberl, M. Vlădescu","doi":"10.1109/SIITME.2013.6743656","DOIUrl":"https://doi.org/10.1109/SIITME.2013.6743656","url":null,"abstract":"A new RFID reader for the 13.56 MHz carrier frequency was developed in the framework of the collaboration between Freaquent Frosch Electronics (FE) and the first author. The reader is intended to cover the standards ISO/IEC FDIS 18000 [1], ISO/IEC FCD 15693 [2] and to provide long-range reading as well as inventory of large collections of tags. The reader features a class E switching power amplifier in the transmission path and several means for achieving a high quality signal in the reception path. Our paper will be focused on the procedures we developed for processing, storing and decoding the signal received from tags.","PeriodicalId":267846,"journal":{"name":"2013 IEEE 19th International Symposium for Design and Technology in Electronic Packaging (SIITME)","volume":"520 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116181813","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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