• Title/Summary/Keyword: mesh networks

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A Vehicle License Plate Recognition Using the Haar-like Feature and CLNF Algorithm (Haar-like Feature 및 CLNF 알고리즘을 이용한 차량 번호판 인식)

  • Park, SeungHyun;Cho, Seongwon
    • Smart Media Journal
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    • v.5 no.1
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    • pp.15-23
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    • 2016
  • This paper proposes an effective algorithm of Korean license plate recognition. By applying Haar-like feature and Canny edge detection on a captured vehicle image, it is possible to find a connected rectangular, which is a strong candidate for license plate. The color information of license plate separates plates into white and green. Then, OTSU binary image processing and foreground neighbor pixel propagation algorithm CLNF will be applied to each license plates to reduce noise except numbers and letters. Finally, through labeling, numbers and letters will be extracted from the license plate. Letter and number regions, separated from the plate, pass through mesh method and thinning process for extracting feature vectors by X-Y projection method. The extracted feature vectors are classified using neural networks trained by backpropagation algorithm to execute final recognition process. The experiment results show that the proposed license plate recognition algorithm works effectively.

Backup path Setup Algorithm based on the Bandwidth Sharing in Mesh Networks (메쉬 구조의 망에서 대역 공유를 통한 복구 경로 설정 알고리즘)

  • 이황규;홍석원
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.1
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    • pp.41-47
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    • 2002
  • Path setup considering QoS is one of the main problems to solve in Internet traffic engineering. In network restoration that is one of the traffic engineering components, to establish a backup path or backup path for a working path to be protected is the main task. The backup path should have enough bandwidth to guarantee the working paths. Thus this work requires the QoS routing solution that is to set up a backup path as well as a working path at the same time provisioning enough bandwidth. In this paper, we propose an algorithm to setup a backup path that shares the bandwidth of other backup paths whose working path does not pass along the same link with the working path we are considering. In this way we can reduce much bandwidth consumption caused by setting up backup paths. We also analyze the disjoint path computation algorithms. Finally we show simulation results how the algorithm can reduce the bandwidth consumption and how it will affect blocking when we setup paths.

AP-Initiated Flow Redirection Mechanism for AP Load Balancing in WLAN Environments (무선랜 환경에서 AP 로드 밸런싱을 위한 AP-개시 플로우 리다이렉션 메커니즘)

  • Kim, Mi-Hui;Chae, Ki-Joon
    • Journal of Internet Computing and Services
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    • v.10 no.2
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    • pp.65-73
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    • 2009
  • IEEE802.11 Wireless LAN(WLAN) is being widely used in public space such as airport, and increases the networking boundary in campus and enterprise, and it has lastly attracted considerable attention for mesh network and converged network with other 3G mobile communication networks. In WLAN, load balancing among Access Points(AP) is an important issue for efficient resource management or supporting the Quality of Service(QoS) of traffic, but most researches focused on the AP selection in network entry or roaming of Stations(STA). In this paper, we propose an AP-Initiated Flow Redirection(FR) for AP load balancing by monitoring AP's availability in the true sense. When the AP's resource becomes almost saturated, that is used more than a specific threshold, the AP queries the roaming possible neighbor APs about their availability and calculates the distribution of traffic load with statistical methods such as entropy or chi-square. Finally, the AP decides flows and new APs for redirection and performs it. Our simulation results show that our FR mechanism increases the performance in the various views.

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Channel assignment for 802.11p-based multi-radio multi-channel networks considering beacon message dissemination using Nash bargaining solution (802.11p 기반 다중 라디오 다중채널 네트워크 환경에서 안전 메시지 전송을 위한 내쉬 협상 해법을 이용한 채널할당)

  • Kwon, Yong-Ho;Rhee, Byung-Ho
    • Journal of Internet Computing and Services
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    • v.15 no.3
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    • pp.63-69
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    • 2014
  • For the safety messages in IEEE 802.11p vehicles network environment(WAVE), strict periodic beacon broadcasting requires status advertisement to assist the driver for safety. WAVE standards apply multiple radios and multiple channels to provide open public road safety services and improve the comfort and efficiency of driving. Although WAVE standards have been proposed multi-channel multi-radio, the standards neither consider the WAVE multi-radio environment nor its effect on the beacon broadcasting. Most of beacon broadcasting is designed to be delivered on only one physical device and one control channel by the WAVE standard. also conflict-free channel assignment of the fewest channels to a given set of radio nodes without causing collision is NP-hard, even with the knowledge of the network topology and all nodes have the same transmission radio. Based on the latest standard IEEE 802.11p and IEEE 1609.4, this paper proposes an interference aware-based channel assignment algorithm with Nash bargaining solution that minimizes interference and increases throughput with wireless mesh network, which is deigned for multi-radio multi-cahnnel structure of WAVE. The proposed algorithm is validated against numerical simulation results and results show that our proposed algorithm is improvements on 8 channels with 3 radios compared to Tabu and random channel allocation algorithm.

Methodology of Shape Design for Component Using Optimal Design System (최적설계 시스템을 이용한 부품에 대한 형상설계 방법론)

  • Lee, Joon-Seong;Cho, Seong-Gyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.672-679
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    • 2018
  • This paper describes a methodology for shape design using an optimal design system, whereas generally a three dimensional analysis is required for such designs. An automatic finite element mesh generation technique, which is based on fuzzy knowledge processing and computational geometry techniques, is incorporated into the system, together with a commercial FE analysis code and a commercial solid modeler. Also, with the aid of multilayer neural networks, the present system allows us to automatically obtain a design window, in which a number of satisfactory design solutions exist in a multi-dimensional design parameter space. The developed optimal design system is successfully applied to evaluate the structures that are used. This study used a stress gauge to measure the maximum stress affecting the parts of the side housing bracket which are most vulnerable to cracking. Thereafter, we used a tool to interpret the maximum stress value, while maintaining the same stress as that exerted on the spot. Furthermore, a stress analysis was performed with the typical shape maintained intact, SM490 used for the material and the minimizing weight safety coefficient set to 3, while keeping the maximum stress the same as or smaller than the allowable stress. In this paper, a side housing bracket with a comparably simple structure for 36 tons was optimized, however if the method developed in this study were applied to side housing brackets of different classes (tons), their quality would be greatly improved.

A Study on the memory management techniques using Sensing Data Filtering of Wireless sensor nodes (무선센서노드의 센싱 데이터 필터링을 사용한 메모리 관리 기법에 대한 연구)

  • Kang, Yeon-I;Kim, Hwang-Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.5
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    • pp.1633-1639
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    • 2010
  • Recently Wireless sensor networks have been used for many purposes and is active for this study. The various methods to reduce energy consumption, which are actively being studied Wireless sensor network to reduce energy consumption, leading to improve transport efficiency, Cluster can be viewed using the research methods. Cluster method researches consists of a sensor node to the cluster and in among those they take out the Cluster head node and Cluster head node is having collects sensing information of circumferential nodes sensing to sink node transmits. Selected as cluster head sensor nodes so a lot of the energy consumption is used as a cluster head sensor nodes is lose a shorter life span have to be replaced by another sensor node. In this paper, to complement the disadvantages of a cluster-mesh method, proposes to manage memory efficiently about filtering method for sensing data. Filtering method to store the same data sensing unlike traditional methods of data filtering system sensing first sent directly by the hashing algorithm to calculate the hash table to store addresses and Sensing to store data on the calculated address in a manner to avoid duplication occurred later, and sensing data is not duplicated by filtering data to be stored in the hash table is a way.