Pub Date : 2018-05-13DOI: 10.1109/CCECE.2018.8447878
B. Trindade, E. Ukwatta, Mike Spence, C. Pawlowicz
One of the most important steps in the extraction of layout for reverse engineering of the integrated circuits (ICs) is the image segmentation of wires and vias from scan electron microscope (SEM) images. This segmentation is challenging due to the gigabytes of image data just for a single IC, image noise, and artefacts. Existing approaches rely on image intensity threshold-based methods but requires significant amount of manual user interactions to correct errors in segmentation. In this paper, we describe an image processing pipeline for segmenting IC layouts from SEM images. Our pipeline includes image normalization, image preprocessing, and segmentation. The segmentation results were compared using a custom-built comparison tool. The results showed, with the correct filters/methods selection, an increase in accuracy of the segmentation for all tested image sets.
{"title":"Segmentation of Integrated Circuit Layouts from Scan Electron Microscopy Images","authors":"B. Trindade, E. Ukwatta, Mike Spence, C. Pawlowicz","doi":"10.1109/CCECE.2018.8447878","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447878","url":null,"abstract":"One of the most important steps in the extraction of layout for reverse engineering of the integrated circuits (ICs) is the image segmentation of wires and vias from scan electron microscope (SEM) images. This segmentation is challenging due to the gigabytes of image data just for a single IC, image noise, and artefacts. Existing approaches rely on image intensity threshold-based methods but requires significant amount of manual user interactions to correct errors in segmentation. In this paper, we describe an image processing pipeline for segmenting IC layouts from SEM images. Our pipeline includes image normalization, image preprocessing, and segmentation. The segmentation results were compared using a custom-built comparison tool. The results showed, with the correct filters/methods selection, an increase in accuracy of the segmentation for all tested image sets.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132276162","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447718
S. A. Alavi, A. Rahimian, K. Mehran, J. A. M. Ardestani
This paper presents a data collection architecture for situational awareness (SA)-centric microgrids. A prototype has been developed which can provide enormous data collection capabilities from smart meters, in order to realise an adequate SA level in microgrids. A communication framework based on the publish-subscribe model is also proposed and implemented for the communication layer of the SA using the message queuing telemetry transport (MQTT) protocol over two different physical (PHY) layers (i.e., WiFi and GPRS). An Internet of things (IoT) platform (i.e., Thingsboard) is used for the SA visualisation with a customised dashboard. It is shown by using the developed system, an adequate level of SA can be achieved with a minimum installation and hardware cost. Moreover, the Modbus protocol over the RS-485 is applied for the smart meter communication.
{"title":"An IoT-Based Data Collection Platform for Situational Awareness-Centric Microgrids","authors":"S. A. Alavi, A. Rahimian, K. Mehran, J. A. M. Ardestani","doi":"10.1109/CCECE.2018.8447718","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447718","url":null,"abstract":"This paper presents a data collection architecture for situational awareness (SA)-centric microgrids. A prototype has been developed which can provide enormous data collection capabilities from smart meters, in order to realise an adequate SA level in microgrids. A communication framework based on the publish-subscribe model is also proposed and implemented for the communication layer of the SA using the message queuing telemetry transport (MQTT) protocol over two different physical (PHY) layers (i.e., WiFi and GPRS). An Internet of things (IoT) platform (i.e., Thingsboard) is used for the SA visualisation with a customised dashboard. It is shown by using the developed system, an adequate level of SA can be achieved with a minimum installation and hardware cost. Moreover, the Modbus protocol over the RS-485 is applied for the smart meter communication.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130037749","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447811
Jiajun Liang, H. Kwan
In this paper, IIR digital filter design using constrained multiobjective Cuckoo Search Algorithm is presented. Minimization of the peak errors in passband and stopband magnitude responses and passband group delay response are performed. The digital filter design results of the constrained MOCSA approach compares favorably with the recent results of other optimization methods
{"title":"IIR Filter Design Using Constrained Multiobjective Cuckoo Search Algorithm","authors":"Jiajun Liang, H. Kwan","doi":"10.1109/CCECE.2018.8447811","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447811","url":null,"abstract":"In this paper, IIR digital filter design using constrained multiobjective Cuckoo Search Algorithm is presented. Minimization of the peak errors in passband and stopband magnitude responses and passband group delay response are performed. The digital filter design results of the constrained MOCSA approach compares favorably with the recent results of other optimization methods","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116624631","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447612
Weifeng Fu, Qingsheng Hu, Rong Wang
This paper presents a 40 Gb/s SerDes receiver for 4-level pulse-amplitude modulation (P AM4) data. After a voltage-shifting amplifier which works as a 3-level slicer, the input P AM4 signal is quantized into thermometer code, and then it is converted into two parallel binary signal by a decoder as the output. Also, an equalizer is designed to deal with the channel attenuation and a Clock and a 20 Gb/s full-rate Clock and Data Recovery (CDR) to recovery correct clock from input data. The whole circuit is designed in 65nm CMOS technology with an area of $1times 0.7 mathbf{mm}^{2}$. Simulation results show that the eye opening of the output data is about 0.9UI and the jitter of the recovered clock is around 3.2 ps. Under 1.2V power supply, the power consumption is about 270mW.
{"title":"A 40 Gb/s PAM4 SerDes Receiver in 65nm CMOS Technology","authors":"Weifeng Fu, Qingsheng Hu, Rong Wang","doi":"10.1109/CCECE.2018.8447612","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447612","url":null,"abstract":"This paper presents a 40 Gb/s SerDes receiver for 4-level pulse-amplitude modulation (P AM4) data. After a voltage-shifting amplifier which works as a 3-level slicer, the input P AM4 signal is quantized into thermometer code, and then it is converted into two parallel binary signal by a decoder as the output. Also, an equalizer is designed to deal with the channel attenuation and a Clock and a 20 Gb/s full-rate Clock and Data Recovery (CDR) to recovery correct clock from input data. The whole circuit is designed in 65nm CMOS technology with an area of $1times 0.7 mathbf{mm}^{2}$. Simulation results show that the eye opening of the output data is about 0.9UI and the jitter of the recovered clock is around 3.2 ps. Under 1.2V power supply, the power consumption is about 270mW.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127077315","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447618
Christian Adrian Farfan, D. M. Marín, D. Chacón-Troya, R. Medina
This document presents an innovative tool for assessing the consequence of the final failure a power transformer, this metric considers aspects as: power quality, overload of other equipment, safety, reliability of the system and the environmental & social impact. For this evaluation, existing standards as well experience and industry practices are integrated. For this regard, a fuzzy inference system was proposed, the membership functions and the rules for integrating each input are based on a survey applied over a set of Ecuadorian power transformers; this study considers technical, economic and social characteristics of the impact of the final failure. The resulting membership functions, and the rules are presented.
{"title":"Assessing Consequences of the Final Failure of a Power Transformer Using Fuzzy Logic and Expert Criteria","authors":"Christian Adrian Farfan, D. M. Marín, D. Chacón-Troya, R. Medina","doi":"10.1109/CCECE.2018.8447618","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447618","url":null,"abstract":"This document presents an innovative tool for assessing the consequence of the final failure a power transformer, this metric considers aspects as: power quality, overload of other equipment, safety, reliability of the system and the environmental & social impact. For this evaluation, existing standards as well experience and industry practices are integrated. For this regard, a fuzzy inference system was proposed, the membership functions and the rules for integrating each input are based on a survey applied over a set of Ecuadorian power transformers; this study considers technical, economic and social characteristics of the impact of the final failure. The resulting membership functions, and the rules are presented.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126412425","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447866
Wenyuan Li, Dehua Zhou
This paper presents a compact frequency output temperature sensor based on the fact that threshold voltage fluctuates according to the temperature. In modern electronic applications, on-chip temperature monitoring is crucial to optimize performance. This paper gives a project of a sensor that has been fabricated using low cost 0.18 $mumathbf{m}$ CMOS technology with a single 1.8 V supply voltage. In order to sense the temperature, the chip get the threshold voltage of the MOSFETs, instead of the usually used base emitter voltage of the bipolar transistor, with the threshold voltage get circuit (VG). Then, with the intention to deal with the high sensitivity voltage signal, VCO is used to transfer the voltage signal into oscillating signal, whose frequency can be seen linearly proportional to the temperature. After one-point trimming, the sensor exhibits a high linearity over a temperature range of 0 to $+150^{circ} mathrm{C}$, achieving sensitivity of $3text{MHz}/^{circ} mathrm{C}$ with the inaccuracy rate of 12%. Also, the power consumption is below 1.2 $mu mathrm{W}$, and the area of the chip is approximately 0.06 $text{mm}^{2}$. These features make this design a highly suitable solution in the case of portable applications.
{"title":"1.8V -0.18-μm CMOS Temperature Sensor with Frequency Output","authors":"Wenyuan Li, Dehua Zhou","doi":"10.1109/CCECE.2018.8447866","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447866","url":null,"abstract":"This paper presents a compact frequency output temperature sensor based on the fact that threshold voltage fluctuates according to the temperature. In modern electronic applications, on-chip temperature monitoring is crucial to optimize performance. This paper gives a project of a sensor that has been fabricated using low cost 0.18 $mumathbf{m}$ CMOS technology with a single 1.8 V supply voltage. In order to sense the temperature, the chip get the threshold voltage of the MOSFETs, instead of the usually used base emitter voltage of the bipolar transistor, with the threshold voltage get circuit (VG). Then, with the intention to deal with the high sensitivity voltage signal, VCO is used to transfer the voltage signal into oscillating signal, whose frequency can be seen linearly proportional to the temperature. After one-point trimming, the sensor exhibits a high linearity over a temperature range of 0 to $+150^{circ} mathrm{C}$, achieving sensitivity of $3text{MHz}/^{circ} mathrm{C}$ with the inaccuracy rate of 12%. Also, the power consumption is below 1.2 $mu mathrm{W}$, and the area of the chip is approximately 0.06 $text{mm}^{2}$. These features make this design a highly suitable solution in the case of portable applications.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132671355","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447713
Shengkai Xu, Dazhuan Xu
In this paper, we investigate Gray-mapped 16-QAM modulated Luby Transform (LT) codes over additive white Gaussian noise (AWGN) channels. Degree distributions for LT codes with a BPSK modulation have been well studied in the literature but those distributions provide unsatisfactory bit-error-rate (BER) performance under high order constellations. To improve the BER performance of LT codes with Gray-mapped QAM, this paper presents a novel optimization design of degree distributions. First, we put forth the concept of variance-to-mean ratio (VMR) in a Gaussian distribution because that the variance is two times larger than the mean in the conventional Gaussian approximation (GA) no longer applies for QAM. Second, we provide a generalized GA process using the obtained VMRs to analyze the asymptotic BER performance of LT codes and furthermore lower bound on BER. Third, aiming at minimizing the average degree of degree distribution, we propose a novel model constrained by the lower bound on BER. Simulation results show that the degree distribution offered by the proposed optimization model can provide outstanding BER performance of LT codes with Gray-mapped 16-QAM over the AWGN channel.
{"title":"Design of Luby Transform Codes with Gray-Mapped 16-QAM Over AWGN Channels","authors":"Shengkai Xu, Dazhuan Xu","doi":"10.1109/CCECE.2018.8447713","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447713","url":null,"abstract":"In this paper, we investigate Gray-mapped 16-QAM modulated Luby Transform (LT) codes over additive white Gaussian noise (AWGN) channels. Degree distributions for LT codes with a BPSK modulation have been well studied in the literature but those distributions provide unsatisfactory bit-error-rate (BER) performance under high order constellations. To improve the BER performance of LT codes with Gray-mapped QAM, this paper presents a novel optimization design of degree distributions. First, we put forth the concept of variance-to-mean ratio (VMR) in a Gaussian distribution because that the variance is two times larger than the mean in the conventional Gaussian approximation (GA) no longer applies for QAM. Second, we provide a generalized GA process using the obtained VMRs to analyze the asymptotic BER performance of LT codes and furthermore lower bound on BER. Third, aiming at minimizing the average degree of degree distribution, we propose a novel model constrained by the lower bound on BER. Simulation results show that the degree distribution offered by the proposed optimization model can provide outstanding BER performance of LT codes with Gray-mapped 16-QAM over the AWGN channel.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130624945","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447538
G. S. Vieira, Fabrízzio Soares, G. Laureano, Rafael T. Parreira, J. C. Ferreira, R. M. Costa, C. B. R. Ferreira
In this work, we propose a simple but an effective technique to adjust a disparity map in a more appropriate configuration. This proposal consists of three main steps: segmentation process, statistical analysis and by using adaptive weighted windows. Furthermore, we investigate if a disparity map, yielded by a robust stereo method, can be improved by the proposed methodology. Thus, we implement some stereo vision methods to compare. The experimental results show that the proposed method is efficient and it can make some enhancements in disparity maps, as reducing the disparity error measure.
{"title":"Disparity Refinement Through Grouping Areas and Support Weighted Windows","authors":"G. S. Vieira, Fabrízzio Soares, G. Laureano, Rafael T. Parreira, J. C. Ferreira, R. M. Costa, C. B. R. Ferreira","doi":"10.1109/CCECE.2018.8447538","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447538","url":null,"abstract":"In this work, we propose a simple but an effective technique to adjust a disparity map in a more appropriate configuration. This proposal consists of three main steps: segmentation process, statistical analysis and by using adaptive weighted windows. Furthermore, we investigate if a disparity map, yielded by a robust stereo method, can be improved by the proposed methodology. Thus, we implement some stereo vision methods to compare. The experimental results show that the proposed method is efficient and it can make some enhancements in disparity maps, as reducing the disparity error measure.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123714890","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447531
M. Masrob, M. Rahman, G. George
This paper implements a novel wavelet-based multiresolution analysis power system stabilizer (WMRA-PSS) for a power system consisting of a synchronous generator connected to an infinite bus system through transmission lines. To overcome the drawbacks of the conventional power system stabilizers that have a design based on a linearized model of the power system, the WMRA-PSS is implemented to enhance the dynamic behaviour of the power system under different operating conditions using MATLAB Simulink. The results verify the efficiency and stability of the suggested WMRA-PSS under different operating conditions.
{"title":"Scheme of a Novel Wavelet-Based Multi-Resolution Analysis Power System Stabilizer","authors":"M. Masrob, M. Rahman, G. George","doi":"10.1109/CCECE.2018.8447531","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447531","url":null,"abstract":"This paper implements a novel wavelet-based multiresolution analysis power system stabilizer (WMRA-PSS) for a power system consisting of a synchronous generator connected to an infinite bus system through transmission lines. To overcome the drawbacks of the conventional power system stabilizers that have a design based on a linearized model of the power system, the WMRA-PSS is implemented to enhance the dynamic behaviour of the power system under different operating conditions using MATLAB Simulink. The results verify the efficiency and stability of the suggested WMRA-PSS under different operating conditions.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123212261","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 : 2018-05-13DOI: 10.1109/CCECE.2018.8447755
Donglin Wang, M. Fattouche, F. Ghannouchi
This paper aims at investigating the feasibility of ranging and positioning in millimeter (mm)-level accuracy by adopting millimeter-wave and 3D massive antenna array. The agent is equipped with massive phased uniform rectangular array (URA) and multiple anchors are considered in localization networks to pursue a higher accuracy, where a far-field environment is assumed for phased massive URA. Fundamental limits of both time-based ranging and positioning are derived by Crámer-Rao bound (CRB), where the relationship between the fundamental bound of range estimation and that of position estimation is theoretically clarified. Numerical results show that the proposed scenario achieves a precise mm-level accuracy for ranging and positioning.
{"title":"Bounds of mmWave-Based Ranging and Positioning with Massive Uniform Rectangular Array","authors":"Donglin Wang, M. Fattouche, F. Ghannouchi","doi":"10.1109/CCECE.2018.8447755","DOIUrl":"https://doi.org/10.1109/CCECE.2018.8447755","url":null,"abstract":"This paper aims at investigating the feasibility of ranging and positioning in millimeter (mm)-level accuracy by adopting millimeter-wave and 3D massive antenna array. The agent is equipped with massive phased uniform rectangular array (URA) and multiple anchors are considered in localization networks to pursue a higher accuracy, where a far-field environment is assumed for phased massive URA. Fundamental limits of both time-based ranging and positioning are derived by Crámer-Rao bound (CRB), where the relationship between the fundamental bound of range estimation and that of position estimation is theoretically clarified. Numerical results show that the proposed scenario achieves a precise mm-level accuracy for ranging and positioning.","PeriodicalId":181463,"journal":{"name":"2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129680358","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：