• Title/Summary/Keyword: System Improvements

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Performance Improvements of DFSA(Dynamic Frame Slotted Aloha) Algorithm through Estimation of Intial frame Size (초기 프레임 크기 예측을 통한 DFSA(Dynamic Frame Slotted Aloha) 알고리즘 성능 개선)

  • Lee, Kang-Won;Lee, Moon-Hyung;Lee, Hyun-Kyo;Lim, Kyoung-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.8
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    • pp.1517-1530
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    • 2017
  • Traditional anti-collision algorithms determine slot size of initial frame based on the information of number of collision slots, idle slots, and success slots. Since there is no information about collision at the beginning of tag information collection, traditional anti-collision algorithms can not determine the initial frame size. Considering that performance of anti-collision algorithm is very sensitive to initial slot size traditional anti-collision algorithms need some improvements. In this study two methods are proposed to determine slot size of initial frame efficiently, through which we can improve the performance of dynamic frame slotted aloha algorithm. To verify the performance of proposed algorithms, 2.4GHz RFID system is used. Throughput and delay time are derived through simulation, which is developed using JAVA. We have seen that proposed algorithm improves throughput by 9.6% and delay time by 9.8%.

A Study on the Design Verification by Using Finite Elements Method and Quality Improvement of Radar by Managing Change Points of 4M (유한요소 기법을 활용한 설계검증 및 4M 변경점 관리를 통한 레이더장비 품질 신뢰성 확보에 관한 연구)

  • Jo, Hee Jin;Pak, Se Jin;Lee, Nam Ho;Jung, Won Yong
    • Journal of Korean Society for Quality Management
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    • v.47 no.3
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    • pp.437-451
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    • 2019
  • Purpose: The purpose of this study is to improve the quality of the PGM system by improving the structure and production process of slip-ring rotary joint for radar. Methods: The improvement measures for each cause are established through failure analysis of broken items. Specifically, changing in the housing to improve the heating system. Changing the transportation method to prevent damage to equipment during transport. Changing work process of the attenuator ring to prevent damage. etc. Results: The results of this study are as follows; improving the heating system reduces heat generated by the attenuator by about 7 degrees and obtain additional temperature margins. Reduction of defect rate because of adding X-band rotary joint run-out measurement test, ESS of slip-ring rotary joint and Transportation improvement(reinforced flight boxes, tube protection, etc). Getting stable VSWR values by improving work process of attenuator overheating due to a bad bonding process. Conclusion: Through this study, improvements were made to slip-ring rotary joint that failed repeatedly for various reasons. As a result of the application of the improvements, the same fault does not occur until now, so we can see that the quality of PGM has improved.

Development of a system architecture for an advanced autonomous underwater vehicle, ORCA

  • Choi, Hyun-Taek;Lee, Pan-Mook
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1791-1796
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    • 2004
  • Recently, great improvements have been made in developing autonomous underwater vehicles (AUVs) using stateof- the-art technologies for various kinds of sophisticated underwater missions. To meet increasing demands posed on AUVs, a powerful on-board computer system and an accurate sensor system with an well-organized control system architecture are needed. In this paper, a new control system architecture is proposed for AUV, ORCA (Oceanic Reinforced Cruising Agent) which is being currently developed by Korea Research Institute of Ships and Ocean Engineering (KRISO). The proposed architecture uses a hybrid architecture that combines a hierarchical architecture and a behavior based control architecture with an evaluator for coordinating between the architectures. This paper also proposed a sensor fusion structure based on the definition of 4 categories of sensors called grouping and 5-step data processing procedure. The development of the AUV, ORCA involving the system architecture, vehicle layout, and hardware configuration of on-board system are described.

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A Study on Life Cycle Extension of T-50 Aircraft Hydraulic Control Valve (T-50 항공기 유압조절 밸브 수명연장 방안)

  • Nam, Yongseo;Kim, Taehwa;Baek, Seungji;Kim, Seunghyu;Song, Seokbon
    • Journal of Aerospace System Engineering
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    • v.4 no.2
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    • pp.16-20
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    • 2010
  • In General, the hydraulic system of T-50 Advanced Trainer is applied to flight control system, wheel & Brake system and fuel system for aircraft operation. The hydraulic system is operation with pressure of 3000psi. and many mechanical parts which is operated by hydraulic system has been stressed in incomplete environment same as heat and friction. for example, Oil leakage had occurred in the shutoff valve of FFP used in a certain period of time. After study, The crack progressed by fatigue due to the irregular hydraulic pressure and vibration has been identified as the reason of oil leakage. This paper presents life cycle extension plans of FFP shutoff valve by configuration improvements of shutoff valve and FFP hydraulic motor.

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Problems and Improvement of Privacy Impact Assessment (개인정보영향평가의 문제점과 개선방안)

  • Choi, Young-hee;Han, Keun-hee
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.26 no.4
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    • pp.973-983
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    • 2016
  • It's been almost 6 years since PIA was implemented based on legislation. So I analyzed problems of PIA from the perspective of ITSM 3 elements. I mainly took account of quality improvement of the report when I assessed systems processing personal informations. So, I propose in terms of logical validity improvement of assessment report. The improvements on 4 different outputs for each phase are many cases that I assessed systems processing personal informations. And I propose improvements on qualified assessors having capability of GRC and on process for managing the assessment system. To settle down PIA system as the reasonable and effective assessment system even after 2016, the statutory deadline for completion of PIA, assessors and appointed assessment firms and authorities should cooperate to complete the assessment system.

A Performance Evaluation of Zone Smoke Control Systems for Railway Underground Transit Passage by Smoke Control TAB (제연 TAB를 통한 철도 지하환승통로의 거실제연설비 성능평가)

  • Seol, Seok-Kyun;Kim, Joon-Hwan;Park, Min-Seok;Oh, Seung-Min;Ahn, Yong-Chul;Choi, Jun-Ho
    • Fire Science and Engineering
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    • v.31 no.1
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    • pp.1-9
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    • 2017
  • This study conducted Testing, Adjusting, and Balancing (TAB), which is a type of field performance evaluation experiment of a zone smoke-control system, at a railway underground transit passage installed with a zone smoke- control system to find problems and improvements for ensuring performance. TAB for the smoke control system was classified into several procedures, such as design data review, duct leakage test, field measurement of the airflow rate, velocity of the fan and duct, and a smoke test. Through the duct leakage test, the system leakage ratio was examined to prove the duct sealing. The iImprovement of the smoke control airflow problems due to the lack of fan static pressure loss was the secured performance. The performance of the smoke control fan was secured by improvements of the smoke control airflow rate problems caused by the loss of static pressure in the intake duct. The smoke test in the smoke control zone confirmed that the damper operating schedule subject was influenced by natural wind or train wind.

Suggestions of Improvements on the Current Academic Journal Evaluation System (학술지 평가제도 개선 방안)

  • Oh, Se-Hee
    • The Journal of the Korea Contents Association
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    • v.12 no.4
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    • pp.495-509
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    • 2012
  • Journals are the main indicator to evaluate the level of the studies of a country. The main purpose of this study is to suggest the improvements of the current journal evaluation system to enhance the level of journal quality. To accomplish the above purpose, the 631 researchers are surveyed by internet for their recognition. The major findings are as follows. Firstly, the current registration process need to be maintained, however, need to reinforce the conditions to level up the journal level and to extend the term for keeping the rate. Secondly, the professionalism and credibility of the appraisers need to be reinforced to increase the equity and rationality of the current evaluation system. Thirdly, the evaluation process for the newly entering journal need to be more strict than the current system. Fourthly, the Korean citation index or Kor-Factor need to be applied to evaluate the domestic journals. Lastly, the restriction policy is need to constrain the number of journals.

Improving the secondary school informatics teacher education system by comparing the teacher education programs of Korea and Japan (한일간 교사양성제도의 비교 및 현황 분석을 통한 중등 정보교사 양성제도 개선방안)

  • Kim, JaMee;Lee, WonGyu
    • The Journal of Korean Association of Computer Education
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    • v.19 no.3
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    • pp.35-53
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    • 2016
  • The quality of teachers is a necessary and sufficient condition for education to accomplish its goals. As informatics education will be taught as a required subject in middle schools starting in 2018, it is more important than anything else to secure high-quality teachers. Accordingly, this study was conducted to compare the informatics teacher education system of Korea with that of Japan in terms of qualifications, licensing and promotion, qualification criteria for teachers, qualifications for informatics teachers and licensing methods. As a result of the comparison three improvements were proposed as follows: The title of the specialized subject must be changed to 'Informatics,' graduate-level education and minor curriculum training courses must be reinforced to enhance the expertise of the teachers, and the qualification system must be changed in such a way as to promote the expertise of the teachers. The improvements proposed in this study will surely contribute to the quality of secondary school informatics teachers.

Operation status and improvement plan of bank's performance evaluation systems - focused on the balanced scorecard - (은행의 성과평가시스템 운영실태와 개선방안 - 균형성과표를 중심으로 -)

  • Lee, Kee Kuk;Chi, Sung Kwon;Lee, Dae Shik
    • Journal of Digital Convergence
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    • v.12 no.11
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    • pp.159-169
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    • 2014
  • I Bank, which is domestic one, has implemented a performance management system based on the balanced scorecards (BSC). The purpose of this study is to understand the status and seek improvements of the performance management system of the bank. To achieve the purpose, this paper makes study about the earlier researches and does empirical study based on the questionnaire survey analysis. After figuring out issues, this paper proposes improvements to operate the performance management system using BSC more properly. The Journal of Digital Policy & Management. This space is for the abstract of your study in English.

Stakeholder's Valuation of Public PMO System Using Laddering (래더링 기법을 이용한 전자정부사업관리 위탁(공공 PMO)제도의 이해관계자 별 가치체계)

  • Back, Hyung-Chung;Park, Chan-Hyuk;Jang, Seong-Yong;Kim, Ja-Hee
    • Journal of the Korea Society for Simulation
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    • v.24 no.4
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    • pp.127-136
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    • 2015
  • The e-government project management consignment system to allow the public PMO has been introduced to resolve the quality management issue and the business risk, pointed out by the reorganized Software Industry Promotion Act. The additional regulation improvements are demanded because the public PMO system cannot settle down due to the different opinions among related parties: owner, operator and PMO. Therefore, to make balanced regulation improvements, the in-depth studies are necessary to analyze the fundamental causes of the disagreement between the related parties. This study analyses the each related party's cognitive structure to perform public PMO successfully and the fundamental reasons that cause the different opinions by applying the cognitive psychological Means-end chain theory, the laddering technique and the HVM, Hierarchical Value Map. In addition, this study analyses the regulations required for the related parties to obtain the expected benefits.