Pub Date : 2014-05-26DOI: 10.1109/LASCAS.2014.6820296
Guilherme Povala, D. Silveira, Lívia Amaral, B. Zatt, M. Porto, L. Agostini
This paper presents an efficient solution for external memory bandwidth reduction focusing in the state-of-art video coding standards, like H.264/AVC and HEVC. The proposed approach is based in reference frame compression using a differential coding and a hardware-efficiently adaptation of the traditional Huffman algorithm, besides, it is a lossless solution and fully complied to state-of-art video coding standards. This solution is entitled DRFVLC (Differential Reference Frame Variable-Length Coder) and it applies an inter-block differential coding to concentrate the values near to zero, and also, it uses one static Huffman table to avoid the cost of the on-the-fly Huffman statistical analysis. The use of DRFVLC reached an average compression rate higher than 46% for the evaluated video sequences, with computational cost of a single differential coding and a VLC, which means the solution is not a bottleneck of the video coding system.
{"title":"An efficient reference frame compression approach for video coding systems","authors":"Guilherme Povala, D. Silveira, Lívia Amaral, B. Zatt, M. Porto, L. Agostini","doi":"10.1109/LASCAS.2014.6820296","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820296","url":null,"abstract":"This paper presents an efficient solution for external memory bandwidth reduction focusing in the state-of-art video coding standards, like H.264/AVC and HEVC. The proposed approach is based in reference frame compression using a differential coding and a hardware-efficiently adaptation of the traditional Huffman algorithm, besides, it is a lossless solution and fully complied to state-of-art video coding standards. This solution is entitled DRFVLC (Differential Reference Frame Variable-Length Coder) and it applies an inter-block differential coding to concentrate the values near to zero, and also, it uses one static Huffman table to avoid the cost of the on-the-fly Huffman statistical analysis. The use of DRFVLC reached an average compression rate higher than 46% for the evaluated video sequences, with computational cost of a single differential coding and a VLC, which means the solution is not a bottleneck of the video coding system.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123805976","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 : 2014-05-26DOI: 10.1109/LASCAS.2014.6820257
B. Montrucchio, M. Rebaudengo, A. Velasco
Embedded and Computer-based systems are subject to transient errors originated from several sources, including the impact of high energy particles on sensitive areas of integrated circuits. The evaluation of the sensitivity of the applications to transient faults is a major issue. The paper presents a new approach for testing the effects of transient faults on the Operating System kernel, specifically focusing on kernel mutex data structure, a key component of the kernel. A Software-implemented Fault Injection tool able to inject faults guaranteeing the non-intrusiveness and repeatability of the fault injection campaign is proposed. An analysis of the results has been performed on a large set of mutexes, in order to evaluate their criticality, in particular during input/output operations. Experimental results, executed on a set of benchmarks programs, show the relevance of the effects of the transient faults on this set of variables. Moreover, a significant percentage of faults can lead to a damage of the system also producing an application failure.
{"title":"Software-implemented fault injection in operating system kernel mutex data structure","authors":"B. Montrucchio, M. Rebaudengo, A. Velasco","doi":"10.1109/LASCAS.2014.6820257","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820257","url":null,"abstract":"Embedded and Computer-based systems are subject to transient errors originated from several sources, including the impact of high energy particles on sensitive areas of integrated circuits. The evaluation of the sensitivity of the applications to transient faults is a major issue. The paper presents a new approach for testing the effects of transient faults on the Operating System kernel, specifically focusing on kernel mutex data structure, a key component of the kernel. A Software-implemented Fault Injection tool able to inject faults guaranteeing the non-intrusiveness and repeatability of the fault injection campaign is proposed. An analysis of the results has been performed on a large set of mutexes, in order to evaluate their criticality, in particular during input/output operations. Experimental results, executed on a set of benchmarks programs, show the relevance of the effects of the transient faults on this set of variables. Moreover, a significant percentage of faults can lead to a damage of the system also producing an application failure.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132369443","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 : 2014-05-26DOI: 10.1109/LASCAS.2014.6820318
A. F. Torres-Monsalve, J. D. Bolanos-Jojoa, Jaime Velasco-Medina
Area measurement is intensively used in the industry to classify objects by its size. This paper presents the hardware design of an embedded system for area measurement using image processing by considering high accuracy, high reliability and minimal time processing. In this case, the hardware implementation algorithms for image processing are described using generic structural VHDL, synthesized on the FPGA EP2C70F896C6N, and verified using an image acquisition system based on the D5M camera and the DE2-70 development kit.
{"title":"Embedded system for area measurement using FPGA","authors":"A. F. Torres-Monsalve, J. D. Bolanos-Jojoa, Jaime Velasco-Medina","doi":"10.1109/LASCAS.2014.6820318","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820318","url":null,"abstract":"Area measurement is intensively used in the industry to classify objects by its size. This paper presents the hardware design of an embedded system for area measurement using image processing by considering high accuracy, high reliability and minimal time processing. In this case, the hardware implementation algorithms for image processing are described using generic structural VHDL, synthesized on the FPGA EP2C70F896C6N, and verified using an image acquisition system based on the D5M camera and the DE2-70 development kit.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126594713","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 : 2014-05-26DOI: 10.1109/LASCAS.2014.6820289
Felipe Navarro, S. Cancino, Enrique Estupinan
This paper presents the development of an application to estimate depth using mobile devices that could help visually impaired people to navigate in everyday sites. The mobile device incorporates a stereo camera system and the application takes advantage of the operating system capabilities, such as parallel computation, hardware configuration, in conjunction with the image processing libraries to implement well known and fast performing algorithms for depth estimation. Each camera is calibrated separately and afterwards a stereo calibration is performed. Depth estimation is calculated using two different algorithms and an evaluation of their performance is presented. The mobile devices handle the computational load fast enough to be able to produce the results within the walk time at normal pace. Depth estimation error is low enough to allow object detection like obstacles, room walls or moving persons.
{"title":"Depth estimation for visually impaired people using mobile devices","authors":"Felipe Navarro, S. Cancino, Enrique Estupinan","doi":"10.1109/LASCAS.2014.6820289","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820289","url":null,"abstract":"This paper presents the development of an application to estimate depth using mobile devices that could help visually impaired people to navigate in everyday sites. The mobile device incorporates a stereo camera system and the application takes advantage of the operating system capabilities, such as parallel computation, hardware configuration, in conjunction with the image processing libraries to implement well known and fast performing algorithms for depth estimation. Each camera is calibrated separately and afterwards a stereo calibration is performed. Depth estimation is calculated using two different algorithms and an evaluation of their performance is presented. The mobile devices handle the computational load fast enough to be able to produce the results within the walk time at normal pace. Depth estimation error is low enough to allow object detection like obstacles, room walls or moving persons.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126662504","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 : 2014-05-26DOI: 10.1109/LASCAS.2014.6820251
Chunyan Wang, Pascal Leduc
The DC component of a signal acquired from the environment often represents the information of the background that is useful in the processing of the component of small signal variations. In this paper, we propose a design method for adaptive voltage amplifiers, of which the gain for the voltage signal varies according to the DC component of the input. The basic circuit units used in the design are 3-transistor common-source amplifiers as such a circuit can be made to operate at a given bias point while the signal amplification gain is modulated by a varying DC component of the input. By using such simple units, one can implement sophisticated nonlinear characteristics of adaptive amplifiers while making the amplification linear at a given input DC level. A design example and the simulation results are also presented to demonstrate the effectiveness of the design method.
{"title":"Design of adaptive voltage amplifiers with an input-DC-level-dependent gain","authors":"Chunyan Wang, Pascal Leduc","doi":"10.1109/LASCAS.2014.6820251","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820251","url":null,"abstract":"The DC component of a signal acquired from the environment often represents the information of the background that is useful in the processing of the component of small signal variations. In this paper, we propose a design method for adaptive voltage amplifiers, of which the gain for the voltage signal varies according to the DC component of the input. The basic circuit units used in the design are 3-transistor common-source amplifiers as such a circuit can be made to operate at a given bias point while the signal amplification gain is modulated by a varying DC component of the input. By using such simple units, one can implement sophisticated nonlinear characteristics of adaptive amplifiers while making the amplification linear at a given input DC level. A design example and the simulation results are also presented to demonstrate the effectiveness of the design method.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133093996","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 : 2014-02-01DOI: 10.1109/LASCAS.2014.6820246
M. Kousoulis, G. Antoniou
This paper proposes generalized circuit and state space realizations for four-dimensional (4D) Finite Impulse Response (FIR) filters. Specifically, lattice and direct-form filter structures are considered. The 4D circuit realizations utilize, for their implementation, a minimum number of delay elements. Further, the dimensions of the state-space vector, of the formulated 4D state space models, are minimal. Examples are given to demonstrate the minimality of their circuit and state-space realizations.
{"title":"4D FIR digital filter realizations","authors":"M. Kousoulis, G. Antoniou","doi":"10.1109/LASCAS.2014.6820246","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820246","url":null,"abstract":"This paper proposes generalized circuit and state space realizations for four-dimensional (4D) Finite Impulse Response (FIR) filters. Specifically, lattice and direct-form filter structures are considered. The 4D circuit realizations utilize, for their implementation, a minimum number of delay elements. Further, the dimensions of the state-space vector, of the formulated 4D state space models, are minimal. Examples are given to demonstrate the minimality of their circuit and state-space realizations.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124930501","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 : 2014-02-01DOI: 10.1109/LASCAS.2014.6820320
Manoj Alwani, S. Johar, Surinder-pal Singh
This paper presents a novel method for protecting privacy sensitive regions inside a digital frame. The purpose is achieved by deteriorating the visual quality of privacy sensitive region by adding probability model based random noise to nonzero quantized transform coefficients of the region. The probabilistic model based noise is generated based on the information from neighboring macroblocks and added only to selective non zero AC transform coefficients to have minimal impact on bit rate. Moreover, the parameters of the probability model are derived from the neighboring blocks inside the frame such that the noise follows characteristics of the frame content. For the purpose of implementation, we used H.264/AVC video coding standard for videos and JPEG image compression standard for images. The probabilistic model based noise is generated using a secret key, which can be shared with the authorized decoder such that the obfuscated region can be completely recovered. In order to limit drifting of obfuscation effect outside the targeted regions, Inter and Intra prediction blocks inside H.264/AVC encoder were modified. Overall, we achieve good obfuscation of selected regions with minimal impact on coding efficiency with the capability to achieve complete reconstruction at the authorized decoder.
{"title":"Transform domain based image / video privacy protection","authors":"Manoj Alwani, S. Johar, Surinder-pal Singh","doi":"10.1109/LASCAS.2014.6820320","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820320","url":null,"abstract":"This paper presents a novel method for protecting privacy sensitive regions inside a digital frame. The purpose is achieved by deteriorating the visual quality of privacy sensitive region by adding probability model based random noise to nonzero quantized transform coefficients of the region. The probabilistic model based noise is generated based on the information from neighboring macroblocks and added only to selective non zero AC transform coefficients to have minimal impact on bit rate. Moreover, the parameters of the probability model are derived from the neighboring blocks inside the frame such that the noise follows characteristics of the frame content. For the purpose of implementation, we used H.264/AVC video coding standard for videos and JPEG image compression standard for images. The probabilistic model based noise is generated using a secret key, which can be shared with the authorized decoder such that the obfuscated region can be completely recovered. In order to limit drifting of obfuscation effect outside the targeted regions, Inter and Intra prediction blocks inside H.264/AVC encoder were modified. Overall, we achieve good obfuscation of selected regions with minimal impact on coding efficiency with the capability to achieve complete reconstruction at the authorized decoder.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133171191","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 : 2014-02-01DOI: 10.1109/LASCAS.2014.6820298
A. Bakhtazad, Rayyan Manwar, S. Chowdhury
A method of forming hidden cavities in bonded silicon wafers using dry etch Bisbenzocyclobutene (BCB) is presented. The cavities are formed by vacuum bonding of partially-cured patterned BCB over a Silicon on Insulator (SOI) wafer and over a bare silicon wafer in a low temperature process. The vacuum bonding process parameters are determined through an iterative process that involves SEM inspection of the BCB layer at the bonding surface to ensure a void and wrinkle free strong bond. The cavities can be as small as 28 μm wide with a support margin of only 10 μm and a height of 800 nm. Cavities of other dimensions can also be realized following the same procedure. The cavities can be used to realize MEMS microphones, capacitive micromachined ultrasonic transducers (CMUT), resonant cavities, and also for protective encapsulation of MEMS and microelectronic dies.
{"title":"Cavity formation in bonded silicon wafers using partially cured dry etch bisbenzocyclobutene (BCB)","authors":"A. Bakhtazad, Rayyan Manwar, S. Chowdhury","doi":"10.1109/LASCAS.2014.6820298","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820298","url":null,"abstract":"A method of forming hidden cavities in bonded silicon wafers using dry etch Bisbenzocyclobutene (BCB) is presented. The cavities are formed by vacuum bonding of partially-cured patterned BCB over a Silicon on Insulator (SOI) wafer and over a bare silicon wafer in a low temperature process. The vacuum bonding process parameters are determined through an iterative process that involves SEM inspection of the BCB layer at the bonding surface to ensure a void and wrinkle free strong bond. The cavities can be as small as 28 μm wide with a support margin of only 10 μm and a height of 800 nm. Cavities of other dimensions can also be realized following the same procedure. The cavities can be used to realize MEMS microphones, capacitive micromachined ultrasonic transducers (CMUT), resonant cavities, and also for protective encapsulation of MEMS and microelectronic dies.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123177973","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 : 2014-02-01DOI: 10.1109/LASCAS.2014.6820275
Ziyang Qi, Kun Ma, Qiang Zhou, Yici Cai
As complexity of VLSI circuits grows, routability has been one of the key factors considered by tree construction algorithms in global routing. Flexibility is a geometric structural property of rectilinear Steiner minimal tree (RSMT), and it is expected to accord with routability and therefore predict the overflow situation. Reference [9] proposed a new definition of flexibility of RSMT, combining RSMT's original flexibility and genetic flexibility, and proved the efficiency of predicting routability utilizing experimental results. However, the flexibility is defined according to the RSMT structure, failing to consider different circumstances of congestion distribution. In order to fix this flaw, we propose the new concept of Congestion-Oriented Flexibility. Further, we propose an effective algorithm to enhance the generalized flexibility. Finally, an RSMT Construction Algorithm based on Congestion-Oriented Flexibility is proposed, which is demonstrated to create a routing result with 12.1% less congestion than FLUTE [1] and congestion-driven Steiner trees [2].
{"title":"RSMT construction algorithm based on Congestion-Oriented Flexibility","authors":"Ziyang Qi, Kun Ma, Qiang Zhou, Yici Cai","doi":"10.1109/LASCAS.2014.6820275","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820275","url":null,"abstract":"As complexity of VLSI circuits grows, routability has been one of the key factors considered by tree construction algorithms in global routing. Flexibility is a geometric structural property of rectilinear Steiner minimal tree (RSMT), and it is expected to accord with routability and therefore predict the overflow situation. Reference [9] proposed a new definition of flexibility of RSMT, combining RSMT's original flexibility and genetic flexibility, and proved the efficiency of predicting routability utilizing experimental results. However, the flexibility is defined according to the RSMT structure, failing to consider different circumstances of congestion distribution. In order to fix this flaw, we propose the new concept of Congestion-Oriented Flexibility. Further, we propose an effective algorithm to enhance the generalized flexibility. Finally, an RSMT Construction Algorithm based on Congestion-Oriented Flexibility is proposed, which is demonstrated to create a routing result with 12.1% less congestion than FLUTE [1] and congestion-driven Steiner trees [2].","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121151697","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 : 2014-02-01DOI: 10.1109/LASCAS.2014.6820300
Andre Faul, J. Naber
A Radio Frequency Identification (RFID)-based pressure sensing system is developed to extend the range of current Intra-Ocular Pressure (IOP) sensing systems. The system described in this work utilizes a unique Electrically Small Antenna (ESA) that measures 7mm × 10mm to receive a 915MHz signal used to power the system. A four-stage Schottky rectifier circuit is used to rectify the received signal and provide dc power via a regulator to a Colpitts oscillator. The Colpitts oscillator senses pressure and provides an output signal that is proportional to the pressure. The system is fabricated using a mature, inexpensive 0.5μm CMOS fabrication process and is capable of operating over a range of 5.4cm.
{"title":"Design and test of a 915MHz, RFID-based pressure sensor for Glaucoma","authors":"Andre Faul, J. Naber","doi":"10.1109/LASCAS.2014.6820300","DOIUrl":"https://doi.org/10.1109/LASCAS.2014.6820300","url":null,"abstract":"A Radio Frequency Identification (RFID)-based pressure sensing system is developed to extend the range of current Intra-Ocular Pressure (IOP) sensing systems. The system described in this work utilizes a unique Electrically Small Antenna (ESA) that measures 7mm × 10mm to receive a 915MHz signal used to power the system. A four-stage Schottky rectifier circuit is used to rectify the received signal and provide dc power via a regulator to a Colpitts oscillator. The Colpitts oscillator senses pressure and provides an output signal that is proportional to the pressure. The system is fabricated using a mature, inexpensive 0.5μm CMOS fabrication process and is capable of operating over a range of 5.4cm.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116815677","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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