Pub Date : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458038
M. Sessinghaus, H. Karl
Data gathering in wireless sensor networks is one of the essential tasks that has to be performed efficiently due to the sensors' limited processing, storage, and communication capabilities. When sensor nodes continuously sense and wirelessly transmit raw sensor readings, predicting such readings might be a promising approach to save energy. This paper examines two adaptive prediction algorithms called as Least Mean Square and Recursive Least Square, integrated in a data gathering framework. A comprehensive simulation study of these algorithms assuming Gaussian processes shows that significant communication savings while guaranteeing a user-defined maximum error can be achieved. Especially, low processing costs and memory usage favor these algorithms for practical sensor node implementations. Finally, we prove the wide applicability of our data gathering framework investigating different kinds of real world sensor traces.
{"title":"Evaluating Adaptive Prediction Filters for Efficient Data Gathering in Wireless Sensor Networks","authors":"M. Sessinghaus, H. Karl","doi":"10.1109/ISSPIT.2007.4458038","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458038","url":null,"abstract":"Data gathering in wireless sensor networks is one of the essential tasks that has to be performed efficiently due to the sensors' limited processing, storage, and communication capabilities. When sensor nodes continuously sense and wirelessly transmit raw sensor readings, predicting such readings might be a promising approach to save energy. This paper examines two adaptive prediction algorithms called as Least Mean Square and Recursive Least Square, integrated in a data gathering framework. A comprehensive simulation study of these algorithms assuming Gaussian processes shows that significant communication savings while guaranteeing a user-defined maximum error can be achieved. Especially, low processing costs and memory usage favor these algorithms for practical sensor node implementations. Finally, we prove the wide applicability of our data gathering framework investigating different kinds of real world sensor traces.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124314768","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458154
M. Ghasemazar, B. Vahdat
Electrical Impedance Tomography (EIT) is a visualization of the internal electric conductivity of an object using measurements performed on its surfaces. As an Inverse problem, the solution can be approximated by means of Artificial Neural Networks. In this paper, an Artificial Neural Network solution to this Inverse Problem is presented. Based on the electrical voltage and current measurements on the boundary of the object, the conductivity distribution has been found and the resulting error is calculated. The error is compared for different Neural Network architectures to detect and minimize the errors caused by the solution method. Also, different Neural Networks were tested in the noisy and noiseless conditions to reach the suitable architecture for each case and investigate the measurement error and noise effects. Other than overall error of the whole circuit, distribution of error in different areas of the object is analyzed.
{"title":"Error Study of EIT Inverse Problem Solution Using Neural Networks","authors":"M. Ghasemazar, B. Vahdat","doi":"10.1109/ISSPIT.2007.4458154","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458154","url":null,"abstract":"Electrical Impedance Tomography (EIT) is a visualization of the internal electric conductivity of an object using measurements performed on its surfaces. As an Inverse problem, the solution can be approximated by means of Artificial Neural Networks. In this paper, an Artificial Neural Network solution to this Inverse Problem is presented. Based on the electrical voltage and current measurements on the boundary of the object, the conductivity distribution has been found and the resulting error is calculated. The error is compared for different Neural Network architectures to detect and minimize the errors caused by the solution method. Also, different Neural Networks were tested in the noisy and noiseless conditions to reach the suitable architecture for each case and investigate the measurement error and noise effects. Other than overall error of the whole circuit, distribution of error in different areas of the object is analyzed.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125967633","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458051
H. M. Hassan, A. Al-Hamadi, S. M. Al-Saleem
The presented work considers a rather challenging interdisciplinary issue associated with psycholinguistic, neurology, and cognitive sciences, in addition to, educational technology. More specifically, this paper introduces an investigational cognitive modeling approach to evaluate phonics method applied for teaching children how to read. Herein, evaluation process performed using two artificial neural network (ANN) models with diverse cognitive learning paradigms. Naturally, suggested models inspired by two cognitive styles observed during teaching reading to children. Those children in elementary school are qualified to learn "basic building blocks" of cognition. Accordingly, presented models are simulating cognitive reading activities on the basis of two diverse cognitive learning paradigms. Hence, statistical analysis of obtained modeling results are considered in evaluation of phonics method, rather than other psycholinguistic science approaches. At system level both presented (ANN) models introduced systematic investigation, and realistic simulation of recognizable observations associated with reading activities using phonics method. Finally, an interesting analogous comparison of both suggested learning models is illustrated versus behavioural animal learning after Pavlov's and Thorndike's original experimental results. Conclusively, some suggestions for future interdisciplinary research work concerned with brain functions (learning and memory) are given.
{"title":"Towards Evaluation of Phonics Method for Teaching of Reading Using Artificial Neural Networks (A Cognitive Modeling Approach)","authors":"H. M. Hassan, A. Al-Hamadi, S. M. Al-Saleem","doi":"10.1109/ISSPIT.2007.4458051","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458051","url":null,"abstract":"The presented work considers a rather challenging interdisciplinary issue associated with psycholinguistic, neurology, and cognitive sciences, in addition to, educational technology. More specifically, this paper introduces an investigational cognitive modeling approach to evaluate phonics method applied for teaching children how to read. Herein, evaluation process performed using two artificial neural network (ANN) models with diverse cognitive learning paradigms. Naturally, suggested models inspired by two cognitive styles observed during teaching reading to children. Those children in elementary school are qualified to learn \"basic building blocks\" of cognition. Accordingly, presented models are simulating cognitive reading activities on the basis of two diverse cognitive learning paradigms. Hence, statistical analysis of obtained modeling results are considered in evaluation of phonics method, rather than other psycholinguistic science approaches. At system level both presented (ANN) models introduced systematic investigation, and realistic simulation of recognizable observations associated with reading activities using phonics method. Finally, an interesting analogous comparison of both suggested learning models is illustrated versus behavioural animal learning after Pavlov's and Thorndike's original experimental results. Conclusively, some suggestions for future interdisciplinary research work concerned with brain functions (learning and memory) are given.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114260309","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458096
Sherif Nour, El Din, Waleed Fakhr, H. Nawito, M. Moniri
Image error localization is a popular topic in image processing. In this paper, we present an efficient technique for hierarchical semi-fragile colour image authentication with improved error localization. The authentication signature is extracted from hierarchal image representation in the automata domain. In the automata domain the self-similarity of the coloured image is represented using hierarchical weighted finite automata. The proposed technique is capable of detecting and localizing malicious attacks as well as colour tampering. Experimental results are presented to demonstrate the effectiveness of the proposed technique for well-known images.
{"title":"Hierarchical Semi-Fragile Colour Image Authentication Using Weighted Finite Automata","authors":"Sherif Nour, El Din, Waleed Fakhr, H. Nawito, M. Moniri","doi":"10.1109/ISSPIT.2007.4458096","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458096","url":null,"abstract":"Image error localization is a popular topic in image processing. In this paper, we present an efficient technique for hierarchical semi-fragile colour image authentication with improved error localization. The authentication signature is extracted from hierarchal image representation in the automata domain. In the automata domain the self-similarity of the coloured image is represented using hierarchical weighted finite automata. The proposed technique is capable of detecting and localizing malicious attacks as well as colour tampering. Experimental results are presented to demonstrate the effectiveness of the proposed technique for well-known images.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125494717","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458204
Y. Salah, Mohamed Atri, R. Tourki
New systems on chip (SoC) design allow one to build heterogeneous systems with several functional units, distributed memories, and interconnections on the same chip. In order to achieve more reuse, flexibility, and performance, bus based interconnections are no more sufficient and Network on Chip concepts are emerged. This paper presents the design of a scalable packet based router allowing data transfer and managing dynamically several communications in parallel. The designed router, described in VHDL on RTL level, was simulated in the case of topologies 2D- mesh and 2D-torus (2x2), (3x3) and then (4x4). The used design methodology is based on VHDL as a description language, simulation and synthesis tools.
{"title":"Design of a 2D Mesh-Torus Router for Network on Chip","authors":"Y. Salah, Mohamed Atri, R. Tourki","doi":"10.1109/ISSPIT.2007.4458204","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458204","url":null,"abstract":"New systems on chip (SoC) design allow one to build heterogeneous systems with several functional units, distributed memories, and interconnections on the same chip. In order to achieve more reuse, flexibility, and performance, bus based interconnections are no more sufficient and Network on Chip concepts are emerged. This paper presents the design of a scalable packet based router allowing data transfer and managing dynamically several communications in parallel. The designed router, described in VHDL on RTL level, was simulated in the case of topologies 2D- mesh and 2D-torus (2x2), (3x3) and then (4x4). The used design methodology is based on VHDL as a description language, simulation and synthesis tools.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130176968","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458175
A. Bonaventura, L. Coluccio, G. Fedele
In this paper, a simple and robust method for frequency estimation of multi-sinusoidal signal from a given discrete sequence of noisy data is proposed. The approach used herein is based on the algebraic derivative method in the frequency domain and it does not make any assumption on the way to collect the samples of the considered signal. The frequencies are estimated without iterations, and explicit relationship between the elementary symmetric functions on the frequencies of the signal and its multiple integrals is given. Due to the use of the process output integrals, the resulting parameters estimation is very robust in the face of large measurement noise in the output. Moreover, for an easy time realization of the estimation, a time-varying linear (unstable) filter is proposed. Finally, the effectiveness of the proposed method is demonstrated through practical and simulated experiments.
{"title":"Frequency estimation of multi-sinusoidal signal by multiple integrals","authors":"A. Bonaventura, L. Coluccio, G. Fedele","doi":"10.1109/ISSPIT.2007.4458175","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458175","url":null,"abstract":"In this paper, a simple and robust method for frequency estimation of multi-sinusoidal signal from a given discrete sequence of noisy data is proposed. The approach used herein is based on the algebraic derivative method in the frequency domain and it does not make any assumption on the way to collect the samples of the considered signal. The frequencies are estimated without iterations, and explicit relationship between the elementary symmetric functions on the frequencies of the signal and its multiple integrals is given. Due to the use of the process output integrals, the resulting parameters estimation is very robust in the face of large measurement noise in the output. Moreover, for an easy time realization of the estimation, a time-varying linear (unstable) filter is proposed. Finally, the effectiveness of the proposed method is demonstrated through practical and simulated experiments.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130266860","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458195
Y. Hasan, A. Hassan
The development of effective image authentication techniques is of remarkably growing interest. Some recently developed fragile, semi-fragile/robust or hybrid-watermarking algorithms not only verify the authenticity of the watermarked image but also provide self reconstruction capabilities. However, several algorithms have been reported as vulnerable to various attacks, especially blind pattern matching attacks, with insufficient security. We propose a new blind dual-domain self-embedding watermarking scheme with more secure embedding processes of the image's blocks fragile signatures and robust approximations and more reliable local alterations detection with auto-correction capabilities, surviving normal image content preserving operations. Hence it prevents falsification, the real threat to authentication.
{"title":"Tamper Detection with Self-Correction Hybrid Spatial-DCT Domains Image Authentication Technique","authors":"Y. Hasan, A. Hassan","doi":"10.1109/ISSPIT.2007.4458195","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458195","url":null,"abstract":"The development of effective image authentication techniques is of remarkably growing interest. Some recently developed fragile, semi-fragile/robust or hybrid-watermarking algorithms not only verify the authenticity of the watermarked image but also provide self reconstruction capabilities. However, several algorithms have been reported as vulnerable to various attacks, especially blind pattern matching attacks, with insufficient security. We propose a new blind dual-domain self-embedding watermarking scheme with more secure embedding processes of the image's blocks fragile signatures and robust approximations and more reliable local alterations detection with auto-correction capabilities, surviving normal image content preserving operations. Hence it prevents falsification, the real threat to authentication.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132607781","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458142
A. Abdaoui, Marion Berbineau, H. Snoussi
In this paper, we propose a reduced complexity interference canceler for a Turbo Space-Time Codes (TSTC) receiver. Actually, the TSTC receiver is based on a linear Minimum Mean Squared Error (MMSE) filter inside an Interference Canceler (IC) loop. In this scheme, considering the matrix inversion cost, the overall complexity remains important for a large number of transmit and receive antennas. In the proposed receiver, we integrate the Generalized Minimum residual method (GMRES) for symbol detection to compute the MMSE filter without matrix inversion. A good tradeoff between performances and complexity is thus achieved for a system with a large number of transmit and receive antennas. The bit error ratio (BER) and the complexity are evaluated with respect to the number of iterations of the GMRES and the number of transmit/receive antennas. A comparison with the existent IC-MMSE is presented and discussed at the end of the paper.
{"title":"GMRES Interference Canceler for doubly iterative MIMO system with a Large Number of Antennas","authors":"A. Abdaoui, Marion Berbineau, H. Snoussi","doi":"10.1109/ISSPIT.2007.4458142","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458142","url":null,"abstract":"In this paper, we propose a reduced complexity interference canceler for a Turbo Space-Time Codes (TSTC) receiver. Actually, the TSTC receiver is based on a linear Minimum Mean Squared Error (MMSE) filter inside an Interference Canceler (IC) loop. In this scheme, considering the matrix inversion cost, the overall complexity remains important for a large number of transmit and receive antennas. In the proposed receiver, we integrate the Generalized Minimum residual method (GMRES) for symbol detection to compute the MMSE filter without matrix inversion. A good tradeoff between performances and complexity is thus achieved for a system with a large number of transmit and receive antennas. The bit error ratio (BER) and the complexity are evaluated with respect to the number of iterations of the GMRES and the number of transmit/receive antennas. A comparison with the existent IC-MMSE is presented and discussed at the end of the paper.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122219586","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458176
N. Sgouros, I. Constantinou, G. Loudos, S.A. Kossida
The electrocardiogram (ECG) is one of the most well studied medical signals. A large number of ECG processing algorithms have being proposed over the years covering the areas of ECG noise filtering, automated diagnostic interpretation and coding. In this work, we propose a robust multi-channel ECG encoder architecture, which operates on 12-channel ECG data. The encoder utilizes highly efficient multi-linear patient specific models for inter-channel prediction and the MPEG-4 audio lossless coding (ALS) architecture for intra-channel prediction and coding. The results of the algorithm show improved performance over standard encoding techniques.
{"title":"Use of the MPEG-4 ALS Architecture and Inter-channel Prediction for Multi-channel ECG Coding","authors":"N. Sgouros, I. Constantinou, G. Loudos, S.A. Kossida","doi":"10.1109/ISSPIT.2007.4458176","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458176","url":null,"abstract":"The electrocardiogram (ECG) is one of the most well studied medical signals. A large number of ECG processing algorithms have being proposed over the years covering the areas of ECG noise filtering, automated diagnostic interpretation and coding. In this work, we propose a robust multi-channel ECG encoder architecture, which operates on 12-channel ECG data. The encoder utilizes highly efficient multi-linear patient specific models for inter-channel prediction and the MPEG-4 audio lossless coding (ALS) architecture for intra-channel prediction and coding. The results of the algorithm show improved performance over standard encoding techniques.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121949713","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458021
Chi Zhang, Hongbin Zhang
In this paper, we propose a new method that could reveal some traces that were left in the tampered digital images without using watermarking technique. Our method is based on detecting the presence of feather operation, which is particularly useful to create a smooth transition between the selected region and its surroundings. The similarity of pixel neighborhood is used as weight coefficient to modulate local entropy value. The forged region can be determined by the value of weighted local entropy precisely. Results of experiments on tampered images will be given.
{"title":"Detecting Digital Image Forgeries Through Weighted Local Entropy","authors":"Chi Zhang, Hongbin Zhang","doi":"10.1109/ISSPIT.2007.4458021","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458021","url":null,"abstract":"In this paper, we propose a new method that could reveal some traces that were left in the tampered digital images without using watermarking technique. Our method is based on detecting the presence of feather operation, which is particularly useful to create a smooth transition between the selected region and its surroundings. The similarity of pixel neighborhood is used as weight coefficient to modulate local entropy value. The forged region can be determined by the value of weighted local entropy precisely. Results of experiments on tampered images will be given.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127068150","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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