Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645831
Masathune Ishihara, N. Sasaoka, I. Yoshio, J. Okello
We propose a blind equalization system using an all-pass filter for de-mixing orthogonal frequency division multiplexing (OFDM) symbols in multiple-input multiple-output (MIMO) - OFDM system. In a conventional blind MIMO equalization, there is a possibility that originally transmitted streams are permutated, resulting in being unable to retrieve desired signals at the receiver. In order to solve the problem, each transmitted stream of the proposed MIMO-OFDM system is pre-filtered by a unique all-pass filter. The filter is referred to as Transmit tagging filter (TT-Filter) in this paper. At a receiver, an inverse filter of the TT-filter is used to blindly equalize a MIMO channel without any permutation. The system was originally designed for constant modulus symbol such as PSK signal. This paper evaluates the performance of a QAM Transmission which is non-constant.
{"title":"MCMA equalization without signal permutation for MIMO-OFDM systems using M-QAM","authors":"Masathune Ishihara, N. Sasaoka, I. Yoshio, J. Okello","doi":"10.1109/ISCIT.2013.6645831","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645831","url":null,"abstract":"We propose a blind equalization system using an all-pass filter for de-mixing orthogonal frequency division multiplexing (OFDM) symbols in multiple-input multiple-output (MIMO) - OFDM system. In a conventional blind MIMO equalization, there is a possibility that originally transmitted streams are permutated, resulting in being unable to retrieve desired signals at the receiver. In order to solve the problem, each transmitted stream of the proposed MIMO-OFDM system is pre-filtered by a unique all-pass filter. The filter is referred to as Transmit tagging filter (TT-Filter) in this paper. At a receiver, an inverse filter of the TT-filter is used to blindly equalize a MIMO channel without any permutation. The system was originally designed for constant modulus symbol such as PSK signal. This paper evaluates the performance of a QAM Transmission which is non-constant.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"150 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130946211","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645821
Weikai Xu, Lin Wang, Zhuhan Jiang
In this paper, a new cooperative protocol based on code-shifted differential chaos shift keying (CS-DCSK) modulation, which is an improved differential chaos shifted keying modulation scheme no requirement delay circuits at autocorrelation receiver (AcR), is proposed. The relay user transmits own data while piggybacks other user's data which are received and decoded at pre-phase utilizing the multiple bit-streams transmission property of generalized CS-DCSK (GCS-DCSK). Moreover, the cooperative user may forward the estimated data only when its data is correctly decoded using cyclic redundancy check (CRC) code, namely selective decode-and-forward (DAF). Simulation results show that the proposed protocol has better performance than that of conventional four phase cooperative protocol in bit error rate (BER) and system throughput.
{"title":"A new user cooperative protocol based on code-shifted differential chaos shift keying modulation","authors":"Weikai Xu, Lin Wang, Zhuhan Jiang","doi":"10.1109/ISCIT.2013.6645821","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645821","url":null,"abstract":"In this paper, a new cooperative protocol based on code-shifted differential chaos shift keying (CS-DCSK) modulation, which is an improved differential chaos shifted keying modulation scheme no requirement delay circuits at autocorrelation receiver (AcR), is proposed. The relay user transmits own data while piggybacks other user's data which are received and decoded at pre-phase utilizing the multiple bit-streams transmission property of generalized CS-DCSK (GCS-DCSK). Moreover, the cooperative user may forward the estimated data only when its data is correctly decoded using cyclic redundancy check (CRC) code, namely selective decode-and-forward (DAF). Simulation results show that the proposed protocol has better performance than that of conventional four phase cooperative protocol in bit error rate (BER) and system throughput.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125488970","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645947
Korakoch Kongsombut, R. Chaisricharoen
Problem in the orchid industry's production is caused by the lack of efficient technical knowledge and timely nursery environmental monitoring. Due to the constraints that the nurserymen have in accessing information, they suffered the hardship in managing the orchid care practices. Therefore, we propose a real-time advisory service by utilizing mobile application for mobility, cloud computing technology for scalability, and push notification service for early notification. The service manages to improve nurserymen decision making in orchid care management, reduce cost and time, and enhance their expertise in orchid production.
{"title":"Real-time advisory service for orchid care","authors":"Korakoch Kongsombut, R. Chaisricharoen","doi":"10.1109/ISCIT.2013.6645947","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645947","url":null,"abstract":"Problem in the orchid industry's production is caused by the lack of efficient technical knowledge and timely nursery environmental monitoring. Due to the constraints that the nurserymen have in accessing information, they suffered the hardship in managing the orchid care practices. Therefore, we propose a real-time advisory service by utilizing mobile application for mobility, cloud computing technology for scalability, and push notification service for early notification. The service manages to improve nurserymen decision making in orchid care management, reduce cost and time, and enhance their expertise in orchid production.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114176217","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645868
A. Suadet, V. Kasemsuwan
A compact class-AB bulk-driven quasi-floating gate current mirror is proposed. The circuit is based on an active class-A current mirror using bulk-driven quasi-floating gate (BD-QFG) MOS transistors and low voltage bulk-input pseudo-differential amplifier. The circuit can operate from a supply voltage as low as VT+VDSAT. The performance of the circuit is verified by SPECTRE, using a standard 0.18 μm CMOS process with a 0.5 V supply voltage. The circuit demonstrates low input impedance (934 Ω) and relatively high output impedance (1.13 MΩ). The circuit can drive the output current 8 times larger than the quiescent current. The power dissipation under quiescent condition is 8.2 μW.
{"title":"A compact class-AB bulk-driven quasi-floating gate current mirror for low voltage applications","authors":"A. Suadet, V. Kasemsuwan","doi":"10.1109/ISCIT.2013.6645868","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645868","url":null,"abstract":"A compact class-AB bulk-driven quasi-floating gate current mirror is proposed. The circuit is based on an active class-A current mirror using bulk-driven quasi-floating gate (BD-QFG) MOS transistors and low voltage bulk-input pseudo-differential amplifier. The circuit can operate from a supply voltage as low as VT+VDSAT. The performance of the circuit is verified by SPECTRE, using a standard 0.18 μm CMOS process with a 0.5 V supply voltage. The circuit demonstrates low input impedance (934 Ω) and relatively high output impedance (1.13 MΩ). The circuit can drive the output current 8 times larger than the quiescent current. The power dissipation under quiescent condition is 8.2 μW.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126569821","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645829
Guofa Cai, Lin Wang, Tingting Huang
In this article the capacity expression is derived for M-ary Differential Chaos Shift Keying (M-DCSK) modulation over additive white Gaussian noise (AWGN) channel. Then the capacity bound curves of M-DCSK are provided by Monte Carlo method. Theoretical analysis and simulation results show that the high dimension DCSK modulation has more obvious capacity advantage than the conventional modulations. So they are appropriate for the power-limited communication systems.
{"title":"Channel capacity of M-ary Differential Chaos Shift Keying modulation over AWGN channel","authors":"Guofa Cai, Lin Wang, Tingting Huang","doi":"10.1109/ISCIT.2013.6645829","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645829","url":null,"abstract":"In this article the capacity expression is derived for M-ary Differential Chaos Shift Keying (M-DCSK) modulation over additive white Gaussian noise (AWGN) channel. Then the capacity bound curves of M-DCSK are provided by Monte Carlo method. Theoretical analysis and simulation results show that the high dimension DCSK modulation has more obvious capacity advantage than the conventional modulations. So they are appropriate for the power-limited communication systems.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127598109","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645851
Zuo Zhao, Shengbing Zhang
The introduction of the full paper discusses that the influence of weak ties to Information Spreading in online social network are different according to different online social network type. In the information exchanged social networks, removing the weak ties have little influence on the information spreading, while in the relationship social network, removing the weak ties have significant influence on the information spreading. An efficient weak ties evaluation algorithm can more accurately find the weak ties in a social network to improve the control effect of information spreading. We study the weak ties evaluation algorithm, use the concept of clustering coefficient between two friends and the global evolution to optimize the initial algorithm, in order to solve some existed problem in the initial algorithm. Analysis and experiences proved that the new algorithm perform better than the initial algorithm and the weak ties are more effective on the information spreading in online social network, but the new algorithm still has little influence on the information spreading in the information exchanged social networks.
{"title":"Research on influence of weak ties to information spreading in online social networks","authors":"Zuo Zhao, Shengbing Zhang","doi":"10.1109/ISCIT.2013.6645851","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645851","url":null,"abstract":"The introduction of the full paper discusses that the influence of weak ties to Information Spreading in online social network are different according to different online social network type. In the information exchanged social networks, removing the weak ties have little influence on the information spreading, while in the relationship social network, removing the weak ties have significant influence on the information spreading. An efficient weak ties evaluation algorithm can more accurately find the weak ties in a social network to improve the control effect of information spreading. We study the weak ties evaluation algorithm, use the concept of clustering coefficient between two friends and the global evolution to optimize the initial algorithm, in order to solve some existed problem in the initial algorithm. Analysis and experiences proved that the new algorithm perform better than the initial algorithm and the weak ties are more effective on the information spreading in online social network, but the new algorithm still has little influence on the information spreading in the information exchanged social networks.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131502509","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645898
Chayanut Petpairote, S. Madarasmi
A face recognition database generally consists of expressionless, frontal face images often referred to as neutral faces. However, we often obtain a facial image from a non-frontal view that may even contain expressions such as anger, joy, surprise, smile, sorrow, and etc. Faces with expressions often cause the underlying face recognition algorithm to fail. In this paper, we present an approach to improve face recognition by warping an image with facial expression to create a neutral, expression-invariant face. We use a modified version of the thin plate splines warping to remove the expression from a probe image with expressions to improve the correctness in face recognition using a gallery of neutral faces. We evaluate our proposed method using 2 well-known facial expression databases; namely, the AR-Face and MUG-FED databases. The experimental results for both databases show that our proposed method significantly improves the accuracy of face recognition under expression variations for the 3 commonly used approaches to face recognition including principal component analysis (PCA), linear discriminant analysis (LDA), and feature-based local binary pattern (LBP).
{"title":"Face recognition improvement by converting expression faces to neutral faces","authors":"Chayanut Petpairote, S. Madarasmi","doi":"10.1109/ISCIT.2013.6645898","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645898","url":null,"abstract":"A face recognition database generally consists of expressionless, frontal face images often referred to as neutral faces. However, we often obtain a facial image from a non-frontal view that may even contain expressions such as anger, joy, surprise, smile, sorrow, and etc. Faces with expressions often cause the underlying face recognition algorithm to fail. In this paper, we present an approach to improve face recognition by warping an image with facial expression to create a neutral, expression-invariant face. We use a modified version of the thin plate splines warping to remove the expression from a probe image with expressions to improve the correctness in face recognition using a gallery of neutral faces. We evaluate our proposed method using 2 well-known facial expression databases; namely, the AR-Face and MUG-FED databases. The experimental results for both databases show that our proposed method significantly improves the accuracy of face recognition under expression variations for the 3 commonly used approaches to face recognition including principal component analysis (PCA), linear discriminant analysis (LDA), and feature-based local binary pattern (LBP).","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"462 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124186749","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645942
S. Promwong, Jiraphan Sahakit, S. Teawehim, B. Ruckveratham
A waveform distortion on human body of an ultra wideband body area network (UWB-BAN) system can be extremely distorted through a channel even for free-space transmission because of antenna dispersion. Therefore, the understand of antenna characteristics, which effects on waveform distortion, is necessary. This paper presents the waveform distortion due to human body for wireless meadical applications based on measurement data. The template waveform is considered at the receiver side to maximize the SNR for evaluation. In this results are evaluate based on the extended Friis' transmission formula. This technique gives very accurate results and is very useful for the design and evaluation of UWB-BAN transmission waveform for wireless medical applications, especially focusing on the effect of template waveform.
{"title":"Human body transfer function model for ultra wideband body area network","authors":"S. Promwong, Jiraphan Sahakit, S. Teawehim, B. Ruckveratham","doi":"10.1109/ISCIT.2013.6645942","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645942","url":null,"abstract":"A waveform distortion on human body of an ultra wideband body area network (UWB-BAN) system can be extremely distorted through a channel even for free-space transmission because of antenna dispersion. Therefore, the understand of antenna characteristics, which effects on waveform distortion, is necessary. This paper presents the waveform distortion due to human body for wireless meadical applications based on measurement data. The template waveform is considered at the receiver side to maximize the SNR for evaluation. In this results are evaluate based on the extended Friis' transmission formula. This technique gives very accurate results and is very useful for the design and evaluation of UWB-BAN transmission waveform for wireless medical applications, especially focusing on the effect of template waveform.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127875363","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645923
C. Bunkhumpornpat, Sitthichoke Subpaiboonkit
In the class imbalance problem, most existent classifiers which are designed by the distribution of balance datasets fail to recognize minority classes since a large number of negative instances can dominate a few positive instances. Borderline-SMOTE and Safe-Level-SMOTE are over-sampling techniques which are applied to handle this situation by generating synthetic instances in different regions. The former operates on the border of a minority class while the latter works inside the class far from the border. Unfortunately, a data miner is unable to conveniently justify a suitable SMOTE for each dataset. In this paper, a safe level graph is proposed as a guideline tool for selecting an appropriate SMOTE and describes the characteristic of a minority class in an imbalance dataset. Relying on advice of a safe level graph, the experimental success rate is shown to reach 73% when an F-measure is used as the performance measure and 78% for satisfactory AUCs.
{"title":"Safe level graph for synthetic minority over-sampling techniques","authors":"C. Bunkhumpornpat, Sitthichoke Subpaiboonkit","doi":"10.1109/ISCIT.2013.6645923","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645923","url":null,"abstract":"In the class imbalance problem, most existent classifiers which are designed by the distribution of balance datasets fail to recognize minority classes since a large number of negative instances can dominate a few positive instances. Borderline-SMOTE and Safe-Level-SMOTE are over-sampling techniques which are applied to handle this situation by generating synthetic instances in different regions. The former operates on the border of a minority class while the latter works inside the class far from the border. Unfortunately, a data miner is unable to conveniently justify a suitable SMOTE for each dataset. In this paper, a safe level graph is proposed as a guideline tool for selecting an appropriate SMOTE and describes the characteristic of a minority class in an imbalance dataset. Relying on advice of a safe level graph, the experimental success rate is shown to reach 73% when an F-measure is used as the performance measure and 78% for satisfactory AUCs.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129208666","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 : 2013-10-24DOI: 10.1109/ISCIT.2013.6645854
S. Kungpisdan, Atipat Thongyon
Session Initiation Protocol (SIP) has gained more acceptability as the number of Voice Over Internet Protocol (VoIP) applications grows significantly. However, SIP itself lacks user privacy, necessary security properties, and has poor performance due to chosen cryptographic operations. A number of security techniques were proposed to address user privacy issues, but they still have limitations in terms of security and performance. In this paper, SIPPEN, a SIP Privacy Enhancement with Nicknames, is introduced. SIPPEN can preserve privacy of SIP users while they communicate. Moreover, a new authentication technique between a user agent and a proxy server is introduced. The results given from our analysis show that the proposed protocol not only has higher security level, but it also has better performance comparing to existing techniques.
{"title":"Improving identity privacy and authentication in SIP transactions","authors":"S. Kungpisdan, Atipat Thongyon","doi":"10.1109/ISCIT.2013.6645854","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645854","url":null,"abstract":"Session Initiation Protocol (SIP) has gained more acceptability as the number of Voice Over Internet Protocol (VoIP) applications grows significantly. However, SIP itself lacks user privacy, necessary security properties, and has poor performance due to chosen cryptographic operations. A number of security techniques were proposed to address user privacy issues, but they still have limitations in terms of security and performance. In this paper, SIPPEN, a SIP Privacy Enhancement with Nicknames, is introduced. SIPPEN can preserve privacy of SIP users while they communicate. Moreover, a new authentication technique between a user agent and a proxy server is introduced. The results given from our analysis show that the proposed protocol not only has higher security level, but it also has better performance comparing to existing techniques.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129283345","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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