• 제목/요약/키워드: local distance

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The Study of Algorithm for Communication Environment Channel Characteristic Embedded Control System and Wireless Communication (무선통신과 임베디드 제어시스템 통신환경의 채널특성 알고리즘에 관한 연구)

  • Kang, Jeong-Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.3B
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    • pp.297-304
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    • 2011
  • MIMO wireless communication embedded systems, and for propagation prediction for indoor and outdoor propagation prediction program incorporates an indoor/outdoor propagation through the simulator can be predicted. This analysis technique developed by the interference between multiple transmitters and a maximum transmission distance issues, the frequency utilization efficiency for a variety of issues, including analysis and prediction becomes possible. Development of the prediction of the conventional methods, but I can consider the environmental characteristics of the ray tracing simulation software to develop and implement an efficient ray tracing, ray tracing techniques and are designed to enable tracked beam analysis of propagation characteristics using information technology by combining the theoretical characteristics of an efficient and well-reflected propagation prediction technique was employed. The frequency of domestic embedded systems, ensure the frequency characteristics and frequency of 3-5GHz band for propagation to investigate the development of local wireless communication technology-based skills needed for securing and jeonpaganseopdeung frequency management techniques to ensure the verification and verified through experiments.

A Study on Korean-chinese Elementary School Facility In China Yanji (중국 연길시 조선족 소학교시설 기초연구)

  • Kim, Jong-Young
    • Journal of the Korean Institute of Educational Facilities
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    • v.18 no.3
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    • pp.13-21
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    • 2011
  • Yanji city in China is a city most populated with Korean-chinese. This study is to examine architectural planning characteristics for Korean-chinese Elementary schools in Yanji city. Currently, this city includes nine Korean-chinese schools. This research has been processed with regards to three broad aspects. Firstly changing processes of school systems, secondly local distributions and networks of school facilities, and thirdly site plans, floor plans and elevations of school buildings were analyzed and examined for finding their characteristics. For this study, seven Han-chinese Elementary schools were also analyzed. The study result are as following: 1. Korean-chinese schools have followed national education policies and also maintained Korean-chinese native education methods. The schools have undergone merger and separation with Han-chinese Elementary schools. Three Korean-chinese Elementary schools in Japan Colonials, two schools in the period of the Republic of China foundation and its growing, and four schools in 1980s were founded. 2. Yanji city administers the networks of Korean-chinese school districts and Han-chinese districts separately. All school districts apply to lkm standard as attending distance. The networks are adjusted as per population change. 3. The characteristics of buildings' site plans, floor plans and elevations are simple. Layouts of the schools are - type or -type centered playground. Building plans show one side corridor type and 5 stories mostly. Elevations stress central parts. Various forms such as finger types do not appear in mass planning since the school curriculum and extracurricular activities are not seemingly active. Han-chinese Elementary schools have similar conditions.

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Performance Enhancement of AODV Routing Protocol Using Interrupt Message in MANET (MANET에서 Interrupt message를 이용한 AODV 라우팅 프로토콜의 성능 개선)

  • Lee, Yun-Kyung;Kim, Ju-Gyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.10
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    • pp.785-800
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    • 2013
  • In MANET, AODV(Ad hoc On-demand Distance Vector) has its advantages as on-demand approach but it also has a disadvantage that the control packet overhead is high compared to other routing protocols. This paper improves the problem caused by Hello messages that are broadcasted periodically to detect the local connectivity and maintain neighbor list. Periodic hello messages reduce the Packet delivery ratio and the efficiency in the limited bandwidth. And its increased Control packet overhead leads to decrease the Residual battery capacity and the Network lifetime. Further, non-reactive nature of periodic hello messages in AODV has also been the source of numerous controversies. In order to solve these problems, this paper improves the performance by using the interrupt driven approach which removes periodic hello messages and decreases the Control packet overhead. Performance comparisons between the traditional AODV and proposed mod_AODV done with network simulator QualNet 5.0 show that the mod_AODV performs better in most performance metrics under scenarios with various values of simulation parameters.

An AODV Re-route Methods for Low-Retransmission in Wireless Sensor Networks (무선센서네트워크에서 저-재전송율을 위한 AODV 경로 재설정 방법)

  • Son, Nam-Rye;Jung, Min-A;Lee, Sung-Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.9A
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    • pp.844-851
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    • 2010
  • Recently, AODV routing protocol which one of the table driven method for the purpose data transmission between nodes has been broadly used in mobile wireless sensor networks. An existing AODV has a little overhead of routing packets because of keeping the routing table for activity route and re-routes to recovery the routes in route discontinuation. However that has faults in that excesses useless of the network bandwidth to recovery the route and takes a lone time to recovery the route. This paper proposes an efficient route recovery method for AODV based on wireless sensor networks in connection breaks. The proposed method. The propose method controls the number of RREQ message considering the energy's node and distance between nodes to restrict the flooding range of RREQ message while expanding the range of local repair. In test results, the proposed method are compared to existing method, the number of drops decrease 15.43% and the delay time for re-route decrease 0.20sec.

Automatic Object Recognition in 3D Measuring Data (3차원 측정점으로부터의 객체 자동인식)

  • Ahn, Sung-Joon
    • The KIPS Transactions:PartB
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    • v.16B no.1
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    • pp.47-54
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    • 2009
  • Automatic object recognition in 3D measuring data is of great interest in many application fields e.g. computer vision, reverse engineering and digital factory. In this paper we present a software tool for a fully automatic object detection and parameter estimation in unordered and noisy point clouds with a large number of data points. The software consists of three interactive modules each for model selection, point segmentation and model fitting, in which the orthogonal distance fitting (ODF) plays an important role. The ODF algorithms estimate model parameters by minimizing the square sum of the shortest distances between model feature and measurement points. The local quadric surface fitted through ODF to a randomly touched small initial patch of the point cloud provides the necessary initial information for the overall procedures of model selection, point segmentation and model fitting. The performance of the presented software tool will be demonstrated by applying to point clouds.

Barcode Region of Interest Extraction Method Using a Local Pixel Directions in a Multiple Barcode Region Image (다중 바코드 영역을 가지는 영상에서 지역적 픽셀 방향성을 이용한 바코드 관심 영역 추출 방법)

  • Cho, Hosang;Kang, Bongsoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.9
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    • pp.2121-2128
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    • 2015
  • In this paper presents a method of extracting reliable and regions of interest (ROI) in barcode for the purpose of factory automation. backgrounds are separated based on directional components and the characteristics of detected patterns. post-processing is performed on candidate images with analysis of problems caused by blur, rotation and areas of high similarity. In addition, the resizing factor is used to achieve faster calculations through image resizing. The input images contained multiple product or barcode for application to diverse automation environments; a high extraction success rate is accomplished despite the maximum shooting distance of 80 cm. Simulations involving images with various shooting distances gave an ROI detection rate of 100% and a post-processing success rate of 99.3%.

Local Analysis of the spatial characteristics of urban flooding areas using GWR (지리가중회귀모델을 이용한 도시홍수 피해지역의 지역적 공간특성 분석)

  • Sim, Jun-Seok;Kim, Ji-Sook;Lee, Sung-Ho
    • Journal of Environmental Impact Assessment
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    • v.23 no.1
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    • pp.39-50
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    • 2014
  • In recent years, the frequency and scale of the natural disasters are growing rapidly due to the global climate change. In case of the urban flooding, high-density of population and infrastructure has caused the more intensive damages. In this study, we analyzed the spatial characteristics of urban flooding damage factors using GWR(Geographically Weighted Regression) for effective disaster prevention and then, classified the causes of the flood damage by spatial characteristics. The damage factors applied consists of natural variables such as the poor drainage area, the distance from the river, elevation and slope, and anthropogenic variables such as the impervious surface area, urbanized area, and infrastructure area, which are selected by literature review. This study carried out the comparative analysis between OLS(Ordinary Least Square) and GWR model for identifying spatial non-stationarity and spatial autocorrelation, and in the results, GWR model has higher explanation power than OLS model. As a result, it appears that there are some differences between each of the flood damage areas depending on the variables. We conclude that the establishment of disaster prevention plan for urban flooding area should reflect the spatial characteristics of the damaged areas. This study provides an improved understandings of the causes of urban flood damages, which can be diverse according to their own spatial characteristics.

Development of Computer Vision System for Individual Recognition and Feature Information of Cow (I) - Individual recognition using the speckle pattern of cow - (젖소의 개체인식 및 형상 정보화를 위한 컴퓨터 시각 시스템 개발 (I) - 반문에 의한 개체인식 -)

  • 이종환
    • Journal of Biosystems Engineering
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    • v.27 no.2
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    • pp.151-160
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    • 2002
  • Cow image processing technique would be useful not only for recognizing an individual but also for establishing the image database and analyzing the shape of cows. A cow (Holstein) has usually the unique speckle pattern. In this study, the individual recognition of cow was carried out using the speckle pattern and the content-based image retrieval technique. Sixty cow images of 16 heads were captured under outdoor illumination, which were complicated images due to shadow, obstacles and walking posture of cow. Sixteen images were selected as the reference image for each cow and 44 query images were used for evaluating the efficiency of individual recognition by matching to each reference image. Run-lengths and positions of runs across speckle area were calculated from 40 horizontal line profiles for ROI (region of interest) in a cow body image after 3 passes of 5$\times$5 median filtering. A similarity measure for recognizing cow individuals was calculated using Euclidean distance of normalized G-frame histogram (GH). normalized speckle run-length (BRL), normalized x and y positions (BRX, BRY) of speckle runs. This study evaluated the efficiency of individual recognition of cow using Recall(Success rate) and AVRR(Average rank of relevant images). Success rate of individual recognition was 100% when GH, BRL, BRX and BRY were used as image query indices. It was concluded that the histogram as global property and the information of speckle runs as local properties were good image features for individual recognition and the developed system of individual recognition was reliable.

Examination on the Mounting Status of Cigar Lighter Receptacle for Vehicles and Analysis of its Tracking Characteristics (차량용 시가 잭의 장착 실태조사 및 트레킹 특성 분석)

  • Choi, Chung-Seog
    • Journal of the Korean Society of Safety
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    • v.24 no.4
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    • pp.28-33
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    • 2009
  • This study examined the mounting status of cigar lighter receptacles for vehicles and analyzed the tracking phenomenon that occurs when foreign material entered a cigar lighter receptacle to obtain data for the analysis of accident investigation. Regardless of the vehicle's output, cigar lighter receptacles are mounted in a vehicle horizontally, vertically, or at tilting or inclined angle. The tilting type cigar lighter receptacle is much easier to use but current leakage resulting from foreign materials (coffee, beverages, water, etc.) falling into the cigar lighter receptacle may cause a fire to start. This study used a vehicle battery (DC 12V) as a power supply for the tracking test and configured its circuit in the same way as that of an electrical device in a vehicle. The tracking phenomenon that occurred in the standby mode of the vehicle exhibited a fine flame and an irregular occurrence of smoke. While this tracking phenomenon was occurring, the leakage current and the reaching distance of the flame were measured to be approximately 930mA and $20{\sim}50cm$, respectively. It is thought that the resultant flame may ignite toluene, dust, cigarettes, etc. It was observed that as the tracking progressed, the internal metal socket melted and a hole was created, the surface of which was also severely carbonized. In addition, the electrical resistance of the carbonized conductive path was measured to be approximately $30{\Omega}$. It is thought that this much resistance may cause local heating when leakage current flows and could ignite any nearby flammable material.

Mobile monitoring system of the Dual LED marine lantern (이중 LED 등명기의 휴대용 모니터링 시스템)

  • Ye, Seong-Hyeon;Han, Soonhee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.8
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    • pp.1948-1954
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    • 2014
  • Advances in IT technology and modernization of AtoN(Aids to Navigation) facility has increased the unmanned operation of AtoN. However, in AtoN facilities, accessibility is low and it is not able to perform maintenance on the bad weather at the time. In connection with this, in this paper, by applying the protocol of the enhanced dual LED marine lantern, we implemented the short-range monitoring system for a mobile terminal. System implemented in this paper can be carried out confirm the operation status, inspection or control of the dual LED marine lantern at a short distance. Also, it is possible to reduce maintenance costs and prevent accidents during inspection of AtoN. At the same time, it enables the operation test easily without disassembling the product, effective AtoN operation is possible. We tested the system that has been implemented using prototype of the LED marine lantern and confirmed state informations and controlled the behavior of the system in real time.