• Title/Summary/Keyword: JOA

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Investigating the Practice of the Use Case Modeling in the Object-Oriented Systems Development (객체지향 시스템 개발에서의 유스 케이스 활용성에 관한 연구)

  • Jeong Seung Ryul;Lim Joa Sang
    • Journal of Information Technology Applications and Management
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    • v.12 no.1
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    • pp.21-34
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    • 2005
  • Object-oriented paradigm has required the fundamental changes in the developers' practice and orientation. However. the relevant literature has not still provided the solid practical methodology but created some myths regarding Use Case modeling. In this study. we attempt to 'demythologize' some key aspects of Use Case Modeling by describing what we have observed in our research and practice. In order to identify the developers' perceptions. the survey methodology was utilized. By discussing the differences between what must be done and what has been done. this study provides rich insights into the better understanding of the Use Case modeling and the successful development of object-oriented systems.

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Design of Lane Keeping Steering Assist Controller Using Vehicle Lateral Disturbance Estimation under Cross Wind (횡풍하의 차량 외란 추정을 이용한 차선 유지 조향 보조 제어기 설계)

  • Lim, Hyeongho;Joa, Eunhyek;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.12 no.3
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    • pp.13-19
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    • 2020
  • This paper presents steering controller for unintended lane departure avoidance under crosswind using vehicle lateral disturbance estimation. Vehicles exposed to crosswind are more likely to deviate from lane, which can lead to accidents. To prevent this, a lateral disturbance estimator and steering controller for compensating disturbance have been proposed. The disturbance affecting lateral motion of the vehicle is estimated using Kalman filter, which is on the basis of the 2-DOF bicycle model and Electric Power Steering (EPS) module. A sliding mode controller is designed to avoid unintended the lane departure using the estimated disturbance. The controller is based on the 2-DOF bicycle model and the vision-based error dynamic model. A torque controller is used to provide appropriate assist torque to driver. The performance of proposed estimator and controller is evaluated via computer simulation using Matlab/Simulink.

A Field Study on the Maintainability of Mission Critical Object-Oriented Systems (기간계 객체지향 시스템의 유지보수성에 관한 현장연구)

  • Lim Joa Sang;Jeong Seung Ryul
    • Journal of Information Technology Applications and Management
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    • v.11 no.3
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    • pp.147-159
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    • 2004
  • Empirical evidence on the maintainability of object-oriented systems is far from conclusive, partly due to lack of representativeness of the subjects and systems used in the study. The present research empirically examined this issue with the systems that are mission-critical. currently operational and maintained by professionals. It was found that the 00 group appeared to consume less time while maintaining more amount of software artifacts than the NOO counterpart. This economical utilization of time appeared evident regardless of software development life cycle. This was due to the usefulness of UML for impact analysis which contributed to effective comprehension and communication. Insufficient design specifications led to ambiguity and costly defects in transferring design solutions to development. Also. the encapsulation of 00 seemed to reduce mental loads at maintenance tasks and improved code reuse. However, the number of files to manage increased and thus. dependency management is required for the 00 systems.

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A Study on Feasibility of Hexagonal Phase ZnS:$Mn^{2+}$ Phosphor for Low-voltage Display Applications

  • Shin, Sang-Hoon;Lee, Sang-Hyuk;You, Yong-Chan;Jung, Joa-Young;Park, Chang-Won;Chang, Dong-Sik
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.815-818
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    • 2002
  • Mn doped hexagonal phase of ZnS has been studied as a yellow-orange phosphor for the application to fluorescent displays operated at low voltages. It was found that luminescence from $Mn^{2+}$ was increased as the Mn concentration was increased up to1.2 mol% of host lattice. This study has been attempted by adding trivalent ions such as $Al^{3+}$ or $Bi^{3+}$ to ZnS:Mn as an agent to do the efficient incorporation of Mn ions into ZnS:Mn lattice, resulting in a significant improvement in the phosphor performance, especially at low voltages.

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Imprecise Alert Reduction Algorithm Using Vulnerability Assessment Data (취약성 분석 데이터를 이용한 부정확한 경고 축약 알고리즘)

  • Yang, Jin-Seok;Kim, Tae-Gyoun;Hong, Soon-Joa;Chung, Tai-Myung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.11a
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    • pp.1031-1034
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    • 2005
  • 침입탐지시스템과 같은 기존의 보안 시스템의 가장 큰 단점 중에 하나는 많은 경고로 인하여 정확한 공격 탐지 분석이 매우 힘들다는데 있다. 이는 관리자의 지식과 경험으로 극복될 수 있지만 관리자의 지식과 경험이 많다 할지라도 관리 네트워크의 범위가 클수록 경고 메시지 분석에 대한 어려움이 존재한다. 또한 관리자에게 보고하는 많은 경고 중에 정확하지 않은 경고가 다수 포함되어 있기 때문에 필요하지 않은 경고까지 분석해야하는 부담을 갖는다. 본 논문에서 제시하는 알고리즘은 보안 시스템의 경고와 취약성 분석 데이터의 상관관계를 분석하여 취약성이 존재하지 않는 공격에 대한 경고 메시지를 필터링한다.

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The Implementation of a Structural Health Monitoring System of Bridge based on Sensor Network (센서 네트워크를 이용한 교량 안전진단 시스템 구현)

  • Park, Chong-Myung;Heo, Nan-Sook;Kim, Dong-Gook;Seo, Dong-Mahn;Lee, Joa-Hyoung;Kim, Yoon;Jung, In-Bum
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.05a
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    • pp.1409-1412
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    • 2005
  • 무선 센서 네트워크는 교량 안전진단(Structural Health Monitoring, SHM)을 위한 효율성, 신뢰성 등의 특징들을 제공한다. 그러나 현재 교량 안전진단은 아날로그 센서를 이용하여 데이터를 수집하고, 유선망을 사용하여 관리프로그램으로 전송하고 있다. 본 논문에서는 무선망에서 동작하는 센서 네트워크를 이용하여 교량 및 노면을 모니터링하기 위한 안전진단 시스템을 구현하였다.

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Phytochemical Compounds from the Underground Parts of Gardenia jasminoides var. radicans Makino (꽃치자 지하부의 식물화학적 성분)

  • Moon, Hyung-In;Oh, Joa-Sub;Kim, Jong-Sik;Chen, Pei-Chun;Zee, Ok-Pyo
    • Korean Journal of Pharmacognosy
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    • v.33 no.1 s.128
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    • pp.1-4
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    • 2002
  • The phytochemical study of the underground parts of Gardenia jasminoides var. radicans Makino (Rubiaceae) led to the isolation of five coumarins. On the basis of spectroscopic evidences, the structures of these compounds were charaterized as ferulic acid(l), 5,8-di-(3-methyl-2,3-dihydroxybutyloxylpsoralen)(2), skimmin(3), uracil(4), $3-0-{\alpha}-D-glucopyranosyl-(1{\rightarrow}4)-{\beta}-D-glucopyranosyloxypeucedanin$ hydrates(5), respectively.

Effects of Hydrophilic Surface Treatment on SUS Substrates by Using Dielectric Barrier Discharge

  • Joa, Sang-Beom;Kang, In-Je;Yang, Jong-Keun;Lee, Heon-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.458-458
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    • 2012
  • Fuel Cell is used stacking metal or polymer substrate. This hydro property of substrate surface is very important. Usually, surface property is hydrophilic. The surface oxidation of SUS is investigated through plasma treatments with an atmospheric-pressure dielectric barrier discharge (DBD) for increasing hydrophilic property. The plasma process makes an experiment under various operating conditions of the DBD, which operating conditions are treatment time, plasma gas mixture ratio, the plasma source supply frequency. Two kinds of SUS substrate, SUS-304 and SUS 316L, were used. Discharge frequency has a crucial impact on equipment performance and gas treatment. After the plasma treatment of a SUS plate, highly improved wettability was noted. But, when high oxygen supply, the substrate damaged seriously.

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Study on Improvement of Diamond Deposition on Al2O3 Ceramic Substrates by a DC Arc Plasmatron

  • Kang, In-Je;Joa, Sang-Beom;Chun, Se-Min;Lee, Heon-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.457-457
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    • 2012
  • We presented plasma processing using a DC Arc Plasmatron for diamond deposition on Al2O3 ceramic substrates. Plasma surface treatments were conducted to improve deposition condition before processing for diamond deposition. The Al2O3 ceramic substrates deposited, $5{\times}15mm^2$, were investigated by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD). Properties of diamond (111), (220) and (311) peaks were shown in XRD. We identified nanocrystalline diamond films on substrates. The results showed that deposition rate was approximately $2.2{\mu}m/h$ after plasma surface treatments. Comparing the above result with a common processing, deposition rate was improved. Also, the surface condition was improved more than a common processing for diamond deposition on Al2O3 ceramic substrates.

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The Design of Computer Interfaces Adaptive to Human Emotion: Current Issues and Research Directions

  • Lim, Joa-Sang;Whang, Min-Cheol
    • Science of Emotion and Sensibility
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    • v.1 no.2
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    • pp.121-131
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    • 1998
  • 컴퓨터 기술이 급속도로 발전함에도 불구하고 사용자의 감성에 반응하는 컴퓨터는 아직 등장하지 않고 있다. 그 결과 사용자는 컴퓨터 작업 과정에서 발생할 수 있는 부정적 감성에 무방비로 노출되어 있으며, 이는 컴퓨터 작업의 효과적 수행을 저해하게 될 것이다. 본 논문은 사용자의 감성이 컴퓨터 작업에 미치는 영향을 고찰하였으며, 이를 통해 감성 컴퓨터의 개념적 구조를 제안하였다. 본 연구에서 제안한 감성 컴퓨터란 사용자 감성의 변화를 포착하고, 부정적 변화에 대응하도록 설계된다. 또한 본 연구에서는 감성 컴퓨터의 구축에 필요한 세 가지 요소, 즉 감성의 측정 및 평가, 신호 처리, 사용자 인터페이스를 중심으로 향후 연구 과제를 도출하였다. 아직 감성 컴퓨터에 대한 연구가 초기 단계인 점을 감안하면, 이에 관한 체계적인 연구가 시급한 실정이다.

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