• Title/Summary/Keyword: distributed applications

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A Study on the Determination of Plane Coordinates Using Single Photo Method (단사진 해석기법을 이용한 평면좌표 결정에 관한 연구)

  • 유복모;박운용;조강연;이용희
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.5 no.2
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    • pp.37-46
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    • 1987
  • The single photo method has a lot of applications in forestry, traffic accident managements, industry, criminal investigation, and in daily life. In this study a new single photo method was developed by classifying into the Space resection method and the 2 Dimensional Perspective Transformation method. Metric and nonmetric cameras were used to analyse the accuracy by means of single photo method, and the errors in coordinates and lengths were studied by changing the number and arrangement of control points to obtain the optimum condition for the single photo method. The influence of number and arrangement of control points on the accuracy was relatively small in case of the Metric WILD P31 and ASAHI PENTAX 6$\times$7 cameras, where as for errors it was a major factor in the Non-metric Nikon FM2. To overcome these defects, at least 6 control points should be used for the errors to be convergent and they should be distributed evenly over the surveying area. It was found that accuracy increased as the object to be photographed was placed in the perpendicular direction to the axis of camera.

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A Study on the Reliability/Safety assessment and improvement of USN Gateway for Train Control (열차제어를 위한 USN Gateway 신뢰성, 안전성 평가 및 향상에 관한 연구)

  • Sin, Duc-Ko;Jo, Hyun-Jeong;Shin, Kyeng-Ho;Song, Yong-Soo
    • Journal of the Korean Society for Railway
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    • v.14 no.5
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    • pp.416-424
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    • 2011
  • The recent development of USN (Ubiquitous Sensor Network) technology has broadened its applications to many fields of industry. The USN technology enables the system to monitor and control the status of distributed sensor nodes based on the low-powered communications. Applying the USN in the train control domain, the operational efficiency can be enhanced, where the reliability and the safety of the system are the key challenges. This paper suggests the system design for evaluating and improving the reliability and safety of the gateway, which is a USN component that manages the radio network among the sensors and collects the information from them. For this purpose, the reliability and the level of safety integrity of a general gateway have been predicted quantitatively and the supplementary design has been proposed for the selected week points. The verification on the reliability and the safety of the improved gateway according to the related standards has been followed. With the results of the study, the applicability of USN gateway for train control systems has been reviewed.

Fabrication of Viewing Angle Direction Brightness-Enhancement Optical Films using Surface Textured Silicon Wafers

  • Jang, Wongun;Shim, Hamong;Lee, Dong-Kil;Park, Youngsik;Shin, Seong-Seon;Park, Jong-Rak;Lee, Ki Ho;Kim, Insun
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.569-573
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    • 2014
  • We demonstrate a low-cost, superbly efficient way of etching for the nano-, and micro-sized pyramid patterns on (100)-oriented Si wafer surfaces for use as a patterned master. We show a way of producing functional optical films for the viewing angle direction brightness-enhancement of Lambertian LED (light emitting diode)/OLED (organic light emitting diode) planar lighting applications. An optimally formulated KOH (Potassium hydroxide) wet etching process enabled random-positioned, and random size-distributed (within a certain size range) pyramid patterns to be developed over the entire (100) silicon wafer substrates up to 8" and a simple replication process of master patterns onto the PC (poly-carbonate) and PMMA (poly-methyl methacrylate) films were performed. Haze ratio values were measured for several film samples exhibiting excellent values over 90% suitable for LED/OLED lighting purposes. Brightness was also improved by 13~14% toward the viewing angle direction. Computational simulations using LightTools$^{TM}$ were also carried out and turned out to be in strong agreement with experimental data. Finally, we could check the feasibility of fabricating low-cost, large area, high performance optical films for commercialization.

Semantic Grid Management System based on the Ontology of Application Software (응용 프로그램 온톨로지 기반 시맨틱 그리드 관리 시스템)

  • Kim, Min-Sung;Yi, Gwan-Su
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.3
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    • pp.65-75
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    • 2008
  • Grid Computing has enabled enormous amount of computational jobs by connecting distributed computing resources. This technology has developed and widely used in various fields. Previous researches usually focused on how to efficiently manage and use the grid resources. However, there was not enough tries to understand and manage information of application softwares in a well-defined structure. Therefore users in application domain need to how about grid deeply to identify and describe the resource requirements matching for each jobs. We introduce a semantic grid management system based on application ontology to overcome this problem. We design and implement the ontology to store various information of the applications. With the ontology, this system can infer the resource requirements from input parameters and input data of the application software and automatically assign appropriate resources by matching the requirement. Also it can transform the information to other forms which grid middlewares can handle. We apply the system to construct an analysis environment of bioinformatics and compare it with other grid systems to explain usefulness of the system.

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Application of SDAHL-74 Watershed Model to a Long Term Runoff Analysis in the Mountainous Watershed (산지유역에 대한 USDAHL-74 유역수문모형의 장기유출 해석적용)

  • 권순국;고덕구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.29 no.2
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    • pp.53-63
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    • 1987
  • Due to their wide range of application, deterministic comprehensive hydrologic models using digital computers have been developed in all countries of the world and researches are being undertaken for their appropriate applications. The aim of this study has been to demonstrate the practical implementation of a physically based distributed hydrologic model, the USDAHL-74 model and to investigate its ability to simulate the long term estimate of water balance quantities in a Korean mountainous watershed. Application of the model to Dochuk watershed indicates the following results. 1.Since the USDAHL-74 model includes all the major components of the hydrologic cycle in agricultural watersheds, thus is comprehnsive, the model seems to have a wide range of application from the fact that simulation results obtained are not only runoff volumes m various time units but their spatial variation as well as even soil moisture within the watershed. 2.An approximate calibration to determine the parameter values in the model using various data obtained from D0chuk shed shows that the simulation error of yearly runoff volume is only 0.6 % and a correlation coefficient between observed daily runoff volume and simulated one is 0.91 in all calibrated period.3.As a verification test of the model, runoff volumes are simulated using 1986 year data without changing the parameter values determined by 1985 year data. The tests show that the USDAHL-74 model is a flexible tool and that realistic production to simulate the long term estimate of runoff in Korean mountainous watershed could be obtained using only a short period of calibration.4. Despite of the encouraging results, there still remain minor problems concerning the practical application of the model to improve the result of simulations. Some of these are the small descrepancies between observed and simulated daily runoff volume appeared in the vicinity of peaks and the recession of1 the daily hydrographs and the model performance for the frozen ground and melting process in the model. 5. Alough the use of parameter with physical significance and the ability to improve calibrations on the basis of physical reasoning represents advantages in the simulation for ungaged watersheds, further researches are needed to use the USDAHL-74 mode to simulate runoff in ungaged watersheds.

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ECG Data Compression Using Adaptive Fractal Interpolation (적응 프랙탈 보간을 이용한 심전도 데이터 압축)

  • 전영일;윤영로
    • Journal of Biomedical Engineering Research
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    • v.17 no.1
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    • pp.121-128
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    • 1996
  • This paper presents the ECG data compression method referred the adaptive fractal interpolation algorithm. In the previous piecewise fractal interpolation(PFI) algorithm, the size of range is fixed So, the reconstruction error of the PFI algorithm is nonuniformly distributed in the part of the original ECG signal. In order to improve this problem, the adaptive fractal interpolation(AEI) algorithm uses the variable range. If the predetermined tolerance was not satisfied, the range would be subdivided into two equal size blocks. large ranges are used for encoding the smooth waveform to yield high compression efficiency, and the smaller ranges are U for encoding rapidly varying parts of the signal to preserve the signal quality. The suggested algorithm was evaluated using MIT/BIH arrhythmia database. The AEI algorithm was found to yield a relatively low reconstruction error for a given compression ratio than the PFI algorithm. In applications where a PRD of about 7.13% was acceptable, the ASI algorithm yielded compression ratio as high as 10.51, without any entropy coding of the parameters of the fractal code.

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Digital Image Watermarking Algorithm using Integer Block Transform (정수 블록 변환을 이용한 디지털 이미지 워터마킹 알고리즘)

  • Oh Kwan-Jung;Ho Yo-Sung
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.5 s.311
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    • pp.57-67
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    • 2006
  • Intellectual property rights are gathering strength theses days. Because digital contents are easily reproduced and distributed by advanced computers and networks. Digital watermarking is one of the best solutions for this problem. Generally, frequency-domain watermarking algorithms are preferred since they are more robust than spatial-domain algorithms. However, coefficients in the frequency domain are floating-point numbers. Thus, it is not easy to manipulate those floating-point coefficients and frequency-domain watermarking algorithms have some limitations in their applications. In order to overcome this difficulty, we employ an integer transform in this paper. In addition, our proposed algerian can extract the watermark from both the spatial and frequency domains. We embed the watermark into a specific bit-plane of mid-frequency coefficients. This is equivalent to the differential energy watermarking (DEW) in the spatial domain. Our simulation results show that the proposed algorithm is imperceptible, good for the watermark payload, and robustness against various attacks. Moreover, it is more efficient than any other algorithm working in only one domain.

Analysis and Design of Mat Foundation for High -Ribe Buildings (초고층 건물의 전면기초(MAT 기초) 해석 및 설계)

  • Hong, Won-Gi;Hwang, Dae-Jin;Gwon, Jang-Hyeok
    • Geotechnical Engineering
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    • v.11 no.2
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    • pp.51-70
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    • 1995
  • Types of foundation of high rise buildings are primarily determined by loads transmitted from super structure, soil bearing capacity and available construction technology, The use of deep foundation of the buildings considered in this study due to the fact that rock of enough bearing capacity is not found down until 90~l00m. When a concentration of high soil pressure must be distributed over the entire building area, when small soft soil areas must be bridged, and when compressible strata are located at a shallow depth, mat foundation may be useful in order to have settlement and differential settlement of variable soils be minimized. The concept of mat foundation will also demonstrate some difficulties of applications if the load bearing demand directly carried down to the load -bearing strata exceeds the load -bearing capacity. This paper introduces both the analysis and design of mat type foundation for high rise buildings as well as the method-ology of modelling of the soil foundation, especially, engineered to redistribute the stress exceeding the soil bearing capacity. This process will result in the wide spread of stresses over the entire building foundation.

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Investigation of Thermal Management Parameters of Metal Hydride Based Hydrogen Storage System (금속수소화물 기반 수소저장시스템의 열관리 인자 조사)

  • PARK, CHU SIK;KIM, JONG WON;BAE, KI KWANG;JEONG, SEONG UK;KANG, KYOUNG SOO
    • Journal of Hydrogen and New Energy
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    • v.29 no.3
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    • pp.251-259
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    • 2018
  • Metal hydride based hydrogen storage under moderate temperature and pressure gives the safety advantage over the gas and liquid storage methods. Still solid-state hydrogen storage including metal hydride is below the DOE target level for automotive applications, but it can be adapted to stationary or miliary application reasonably. In order to develop a modular solid state hydrogen storage system that can be applied to a distributed power supply system composed of renewable energy - water electrolysis - fuel cell, the heat transfer and hydrogen storage characteristics of the metal hydride necessary for the module system design were investigated using AB5 type metal hydride, LCN2 ($La_{0.9}Ce_{0.1}Ni_5$). The planetary high energy mill (PHEM) treatment of LCN2 confirmed the initial hydrogen storage activation and hydrogen storage capacity through surface modification of LCN2 material. Expanded natural graphite (ENG) addition to LCN2, and compression molding at 500 atm improved the thermal conductivity of the solid hydrogen storage material.

MPLS and Video Stream broadcast multicast transport optimization through convergence (MPLS와 멀티캐스트 융합을 통한 Video Stream 방송 전송 최적화)

  • Hwang, Seong-Kyu;Han, Seung-Jo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1330-1336
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    • 2014
  • QoS techniques and transmitted in real-time communication with the advancement of technology a variety of applications and services are available these days, mobile devices bogeuphwa LTE technology to the development of multimedia services with high quality can be realized. In order to satisfy this condition simply with a router with an increased bandwidth expansion by considering the increase in the routing table of the network scalability problems included. Burst traffic data to be distributed according to the environment is to be centered. To do this, the destination -based routing method to transmit the current paper -based (Source routing) routing settings are required. In this paper, published by the IETF, IP switching system based on standardized protocol Label Switching Multi-Protocol Label Switching (MPLS) network by using the existing Best Effect is difficult to guarantee QoS for multimedia transmission in MPLS network environment using optimized QoS guarantees to transmit the multicast.