2008 IEEE/ACS International Conference on Computer Systems and Applications最新文献

{"title":"Enhancement of IEEE 802.11 DCF backoff algorithm under heavy traffic","authors":"Issam Elarbaoui, H. Refai","doi":"10.1109/AICCSA.2008.4493682","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493682","url":null,"abstract":"The contention window size in carrier sense multiple access is crucial to the performance of a wireless network because it affects the network throughput and delay characteristics. The basic distributed coordination function (DCF) access mechanism of 802.11 standard describes multiple backoff window sizes. When a terminal is poised to transmit a packet, the smallest window is selected. If a collision occurs, the terminal selects an alternate backoff window. The selection is made in declining consecutive size until the largest one available at that given time is selected. This phenomenon occurs under heavy traffic conditions in which many terminals are accessing the wireless channel at the same time. Once a terminal successfully transmits its packet, the backoff window size reverts to the smallest size for future transmissions; however, this mechanism performs poorly under heavy traffic. This paper proposes that after a successful transmission, backoff window selection is dependent upon the number of retransmission; in other words, it is adaptive to the traffic condition of the network. This approach can alleviate retransmission rate by spreading the chances of simultaneous transmissions more evenly and with better flexibility relative to the basic DFC access mechanism of 802.11 MAC protocol. The MAC adopted for DSRC inter-vehicle communication applications provides enhanced delay properties,- mainly less delay due to collision-as well as throughput of the network. In our scheme a retransmission attempt of a terminal following the successful transmission of another will perform in one of two scenarios, and both are dependent upon the number of retransmissions occurring during a previous attempt Some terminals that reach a successful transmission after exceeding a certain value n will have to select a larger \"minimum contention window,\" while others will select a smaller one. A mathematical model is developed for this proposed scheme. Our simulation experiments validate the analytical results reported in the model, which was analyzed under various assumptions. Thus, the accuracy of our model is verified.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121701528","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}

{"title":"Comparative performance evaluation of software-based fault-tolerant routing algorithms in adaptively-routed tori","authors":"F. Safaei, A. Khonsari, Amirhossein Shantia","doi":"10.1109/AICCSA.2008.4493572","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493572","url":null,"abstract":"Fault-tolerance and network routing have been among the most widely studied topics in the research of parallel processing and computer networking. A fault- tolerant routing algorithm should guarantee the delivery of messages in the presence of faulty components. In this paper, we present a comparative performance study of nine prominent fault-tolerant routings in 2D wormhole-switched tori. These networks carry the software-based routing scheme which has been suggested as an instance of a fault-tolerant method widely used in the literature to achieve high adaptivity and support inter-processor communications in parallel computer networks due to its ability to preserve both communication performance and fault-tolerant demands in such systems. The performance measures studied are the throughput, average message latency, power, and average usage of virtual channels per node. Results obtained through simulation suggest two classes of presented routing schemes as high performance candidates in most faulty networks.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114854911","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}

{"title":"A Recursive Load Balancing technique for VoIP-dedicated WLANs","authors":"G. Sawma, I. Aib, K. Barbar, G. Pujolle","doi":"10.1109/AICCSA.2008.4493623","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493623","url":null,"abstract":"Intelligent and dynamic management is essential for improving WLAN efficiency, especially when multimedia and other QoS demanding applications are employed. In this paper, we propose a Recursive Autonomic Load Balancing Algorithm (RALBA)for WLANs and test its applicability for a VoIP over WLAN (VoWLAN) use case. A load metric is used to identify how many VoIP flows the WLAN cell can support. RALBA uses a Knowledge Plane to obtain high- level information about network state. The algorithm is presented and illustrated along with implementation plans.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131511508","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}

{"title":"Numeral recognition using curvelet transform","authors":"Farhad Mohamad Kazemi, J. Izadian, Reihaneh Moravejian, E. Kazemi","doi":"10.1109/AICCSA.2008.4493593","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493593","url":null,"abstract":"This paper proposes the performance of two new algorithms for digit recognition. These recognition systems are based on extracted features on the performance of image's curvelet transform & achieving standard deviation and entropy of curvelet coefficients matrix in different scales & various angels. In addition, the proposed recognition systems are obtained by using different scales information as feature vector. So, we could clarify the most important scales in aspect of having useful information .Finally by employing the Knn classifier we classify them into predefined classes. The classifier was trained and test with handwritten numeral database, MNIST The results of this test shows, that our correct recognition rate in \"curvelet transform+ standard deviation\" algorithm is 93% and in \"curvelet transform+ entropy\" algorithm is 82%.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132598172","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}

{"title":"A fuzzy clustering algorithm for finding arbitrary shaped clusters","authors":"M. Baghshah, S. Shouraki","doi":"10.1109/AICCSA.2008.4493587","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493587","url":null,"abstract":"Until now, many algorithms have been introduced for finding arbitrary shaped clusters, but none of these algorithms is able to identify all sorts of cluster shapes and structures that are encountered in practice. Furthermore, the time complexity of the existing algorithms is usually high and applying them on large datasets is time-consuming. In this paper, a novel fast clustering algorithm is proposed. This algorithm distinguishes clusters of different shapes using a two- stage clustering approach. In the first stage, the data points are grouped into a relatively large number of fuzzy ellipsoidal sub-clusters. Then, connections between sub-clusters are established according to the Bhattacharya distances and final clusters are formed from the resulted graph of sub-clusters in the second stage. Experimental results show the ability of the proposed algorithm for finding clusters of different shapes.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115228848","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}

{"title":"Wavelets: An efficient tool for lung sounds analysis","authors":"F. Ayari, A. Alouani, M. Ksouri","doi":"10.1109/AICCSA.2008.4493633","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493633","url":null,"abstract":"The objective of this paper is to use adaptive wavelets for lung sounds analysis and show that wavelets with one vanishing moment can successfully detect pathological changes of the lung which produce sounds with measurable regularities. Local regularity measures allow us to detect some significant components of adventitious sounds which are difficult to detect by the physician ears due to their short duration. This paper will concentrate on a development of lung sounds pattern recognition features. The key properties of pattern recognition features, Lipschitz regularity at any point of wavelet transform modulus maxima along the maxima lines converging to this point, regularity of some adventitious lung sounds such as Crackles and Wheezes will be analyzed. Numerical results prove that normal lung sound is more regular than crackles lung sounds.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115655722","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}

{"title":"A video-based image processing system for the automatic implementation of the eye involuntary reflexes measurements involved in the Drug Recognition Expert (DRE)","authors":"F. Meunier, D. Laperrière","doi":"10.1109/AICCSA.2008.4493592","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493592","url":null,"abstract":"In order to detect drivers under the influence of substances such as alcohol or drugs, police officers use a standardized set of tests such as the Horizontal Gaze Nystagmus (HGN) test, the eye convergence test and the pupil's reaction to light test. These tests are part of the more complete Drug Recognition Expert (DRE) procedures and are essentially applied to the eyes of a driver. These procedures are performed manually by law enforcement officers. The present work describes a video-based image processing system implementing the HGN test, the convergence test and the pupil's dark room examinations test. This system generates visual stimuli and captures video sequences of the eyes following and reacting to these visual stimuli. The video sequences are processed and analyzed using feature extraction techniques. In the present study, the video-based image processing system is used to detect alcohol related intoxication. This system was tested in an experiment involving 32 subjects dosed to a blood alcohol concentration (BAC) in the interval of 0.04% to 0.22%. In order to demonstrate the effects of alcohol on eye signs comparisons are made between pre-dose and post-dose BAC.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124211132","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}

{"title":"An MPLS-DiffServ experimental core network infrastructure for E2E QoS content delivery","authors":"N. Zotos, G. Xilouris, E. Pallis, A. Kourtis","doi":"10.1109/AICCSA.2008.4493658","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493658","url":null,"abstract":"The continuing and rapid growth of the Internet has created an extremely large capacity problem to the service and content provider's networks. The increased network traffic and the absence of service priority, usually produce high network congestions, delayed data and service transmissions and lack of throughput. The effect of these factors in AW content transmission is to distort the initial content and decrease the content quality. To avoid this negative effect, service and content providers are looking for architectures that give them greater control on traffic passing through their domains and other heterogeneous networks. This document proposes an experimental core network architecture (MPLS-DiffServ) presenting a solution for content providers that want reliable and agreed level of quality, even if the network is under congestion. MPLS-DiffServ architecture, couples the DiffServ'sper hop guarantees with MPLS traffic engineering capabilities. Furthermore, content/services of different format will be distributed over MPLS-DiffServ network with different guarantee limits and delivered on a variety of user terminals..","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114337479","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}

{"title":"Handover and class-based Call Admission Control policy for 4G-heterogeneous mobile networks","authors":"T. Bejaoui, N. Nasser","doi":"10.1109/AICCSA.2008.4493560","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493560","url":null,"abstract":"In this paper we propose a handover and class-based Call Admission Control algorithm for UMTS/WLAN heterogeneous networks. Its main objective is to limit the occurrence of hard WLAN-UMTS handovers to mobile nodes moving across cells and using real time applications. Our mechanism is based on the service class differentiation, the call origination point, and a vertical handoff decision function as well. It aims at maximizing the utilization of the resources available at the WLAN cells, and meeting the QoS requirement of higher priority users as much as possible while maintaining the minimum requirements of lower priority users, especially when the UMTS and the WLAN networks suffer from congestion. The new CAC policy achieves a good performance and capacity gain.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114624453","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}

{"title":"Performance enhancement through hybrid replication and Genetic Algorithm co-scheduling in data grids","authors":"Ali Elghirani, Riky Subrata, Albert Y. Zomaya, A. Mazari","doi":"10.1109/AICCSA.2008.4493570","DOIUrl":"https://doi.org/10.1109/AICCSA.2008.4493570","url":null,"abstract":"In data grid environments data-intensive applications require large amounts of data to execute. Data transfer is a primary cause of job execution delay. In this paper we study smart scheduling integrated with replica management optimization to improve system performance. We study the use of genetic algorithm (GA) for the scheduling phase of data-intensive applications. The schedulers proposed incorporate information about the datasets and their replicas needed by the jobs to be scheduled, and co-schedules the jobs and the datasets to the computation node guaranteeing minimum job execution time. We employ a data grid replica management framework for the optimization phase of the replica distribution. In this approach we try to achieve a double optimization effect from both the replica management and the scheduling phases, while integrating scheduling and data replication to improve the performance of the grid system. We evaluate and compare our genetic algorithm (GA) with a Tabu search (TS) and the de facto max-min based schedulers.","PeriodicalId":234556,"journal":{"name":"2008 IEEE/ACS International Conference on Computer Systems and Applications","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116896341","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}