• Title/Summary/Keyword: Pilot point

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Design and Implementation of High-availability System (임무컴퓨터를 위한 고가용 시스템의 설계 및 구현)

  • Jeong, Jae-Yeop;Lee, Cheol-Hoon
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.529-533
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    • 2008
  • Mission Computer performs important role both managing a whole system and dealing with a specific mission in avionics system. In general, the fault of SPOF(Single Point Of Failure) in unity system can lead to failure of whole system. It can cause a failure of a mission and also can threaten to the life of the pilot. So, in this paper, we design the HA(High-availability) system so that dealing with the failure. And we use HA software like Heartbeat, Fake, DRBD and Bonding to managing HA system.

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A Qualitative Approach to eIT Project Management (e-비즈니스 IT 프로젝트 관리의 정성적 접근 모형의 개발)

  • Jeong, Gi-Ho
    • Journal of Information Technology Services
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    • v.1 no.1
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    • pp.45-55
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    • 2002
  • This paper suggests a new approach to IT project management based on a regular project meeting results to consider the recent project environment. The greater part of recent IT projects are related to e-business transformation. Transforming to e-business is a new problem very different from those they have been worked, in several point of views. Under e-business era, therefore any IT project is being implemented in more complex, dynamic and uncertain environment than traditional. That is, project leaders must consider more factors to control projects including resources, quality, risks, and technologies, and human resources. The project organizations and software corporations thus need to develop and establish new concepts or methodologies to manage e-business projects. In this point of view, an entropy model in this study is introduced for estimating and managing the uncertainty in project control using multi-attributes of project meeting. This paper proposes a new frame work based on entropy model using project meeting results to consider eIT project environment with a small pilot study.

Least Square Channel Estimation Scheme of OFDM System using Fuzzy Inference Method (퍼지 추론법을 적용한 OFDM 시스템의 LS(Least Square) 채널추정 기법)

  • Kim, Nam;Choi, Jung-Hun
    • The Journal of the Korea Contents Association
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    • v.9 no.5
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    • pp.84-90
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    • 2009
  • In this paper, the new channel estimation was proposed that have the low complexity and high performance using Fuzzy inference method uses recently from various field for estimation about uncertainty in channel estimation of OFDM. Proposed method is channel estimation performance improve, calculation and interpolation for statistics character of channel using the pilot before LS channel estimation by Fuzzy inference method. Simulation result in QPSK proposed channel estimation method shows the enhancement of 5.5dB compared to the LS channel estimation and the deterioration of 1.3dB compared to the MMSE channel estimation in mean square error point $10^{-3}$. symbol error rate shows similarity performance the MMSE $10^{-1.96}$, proposed channel estimation $10^{-1.93}$ and enhancement of $10^{-0.35}$ compared to the LS channel estimation in signal to noise ratio point 20dB.

A Battery Charger Using Photovoltaic Energy Harvesting with MPPT Control (빛 에너지 하베스팅을 이용한 MPPT 제어 기능을 갖는 배터리 충전기)

  • Yoon, Eun-Jung;Yang, Min-Jae;Yu, Chong-Gun
    • Journal of IKEEE
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    • v.19 no.2
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    • pp.201-209
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    • 2015
  • This paper describes a battery charger using photovoltaic energy harvesting with MPPT control. The proposed circuit harvests maximum power from a PV(photovoltaic) cell by employing MPPT(Maximum Power Point Tracking) control and charges an external battery with the harvested energy. The charging state of the battery is controlled according to the signals from a battery management circuit. The MPPT control is implemented using linear relationship between the open-circuit voltage of a PV cell and its MPP voltage such that a pilot PV cell can track the MPP of a main PV cell in real time. The proposed circuit is designed in a $0.35{\mu}m$ CMOS process technology and its functionality has been verified through extensive simulations. The maximum efficiency of the designed entire system is 86.2% and the chip area including pads is $1.35mm{\times}1.2mm$.

Characteristics of Hydaulic Conductivity in Middle-Jeju watershed (제주도 중제주유역의 수리전도도 특성)

  • Kim, Min-Chul;Yang, Sung-Kee;Lee, Jun-Ho;Yang, Won-Seok
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.386-386
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    • 2017
  • 지하수 해석을 위해 3차원 수치해석 모형이 적용되고 있으나, 다양한 매개변수를 명확히 적용하기에는 한계가 있다. 특히, 수리전도도는 지층의 투수성정도를 나타내는 계수로 지하수 분석에 매우 중요한 매개변수이다. 신뢰성의 확보를 위해 양수시험을 통해 산출된 결과를 이용하고 있으나 소수관정의 시험결과를 유역의 대푯값으로 적용하기에 불확실도가 매우 높고, 수위변화가 독특한 지역의 정확한 수리특성을 적용하기에 한계가 있다. 이 연구에서는 수리전도도 특성을 해석하기 위하여 3차원 수치해석모형을 적용하였으며, 모델보정 방법 중 Regularization(정규화)라고 불리는 Pilot point 기법을 사용하였다. 제주도와 같이 수리전도도 값이 지역별로 차이가 크고 동일 유역 내에도 다른 지질구조를 보이는 등 동일 매질에서 동일 투수성을 보이지 않는 다양함으로 실측값들을 적용하기에 어려운 곳에서 정규화라는 보정방법은 최적화된 방법이다. 지하수위는 중제주유역 내 위치한 12개소 수위관측정의 2016년 연평균수위를 적용하였다. 미계측지역은 제주도 등수위선자료를 이용하여 DEM을 구축하였으며, 임의지점 17개소를 선정하여 대표수위로 적용하였다. 중제주유역의 평균 수리전도도는 82.90 m/day로 분석되었으며, 유역의 동측 하류부는 최대 1,745 m/day로 비교적 큰 결과가 산출되었다. 유역의 중앙에 위치하는 OR관측정을 기준으로 동 서지역의 지하수위를 검토한 결과 서측은 지형구배에 따라 지하수위가 형성하고 있으나, 동측의 경우 상 하류의 표고차가 30m이상 발생되지만 지하수위는 유사한 형태를 보이고 있다. 지하수 흐름에 해석되는 Darcy의 방정식은 수리전도도와 동수경사는 반비례관계를 나타내며, 이 이론에 의해 상 하류 지하수위가 유사하게 형성되는 동측지역은 국부적으로 수리전도도가 높게 형성되는 것으로 확인되었다. 실무에서는 유역경계에 따라 평균화된 매개변수가 적용되므로 명확한 지하수 해석이 어렵고, 수리전도도와 같이 지역적 편차가 심한 매개변수는 다양한 연구를 통해 적용성검토가 수행되어야 한다.

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Quantification of uncertainty in hydrogeological characteristics using parameter estimation method (매개변수 보정법을 활용한 수리지질특성의 불확실성 정량화)

  • Tae Beom Kim;Chaeryung Oh;Dongwon Park;Chihyung Lee
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.401-401
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    • 2023
  • 터널이나 폐기물저장소와 같은 지하 구조물 또는 지표에서부터 상당한 깊이로 설계되거나 건설되는 구조물을 계획하거나 건축할 때 구조물의 안전성에 영향을 주는 수많은 요인 중에 간과할 수 없는 것이 바로 지하수이다. 뿐만 아니라 지상 혹은 지하에서 오염이 발생하여 오염물질이 지중환경으로 유입되는 경우, 지하수 거동은 오염물의 이송·확산에 지대한 요인으로 작용한다. 최근에는 지구온난화와 같은 유례없는 기후변화를 경험하고 있고, 따라서 수자원으로써 지하수의 역할이 더욱 중요해지고 있다. 지하수의 저류와 거동은 지하매질의 특성에 지배되고 있지만, 지표 아래 자리잡고 있는 매질의 특성을 정확히 파악하기란 매우 힘들고, 따라서 지하수 거동을 해석함에 항상 불확실성이 존재한다. 전통적으로 지하매질의 특성을 이해하기 위해 다양한 지구물리탐사를 수행하여 왔고, 더욱 직접적인 관찰을 위해 시추를 수행하여, 시료를 수집·관찰하고, 시추공에서의 다양한 현장수리실험을 통해 수리특성을 알고자 하였다. 하지만 그동안의 다양한 노력에도 불구하고, 지하매질 및 지하수 거동에 대한 불확실성은 여전히 줄어들지 않고, 오히려 증가하고 있다. 따라서, 본 연구에서는 지하수 거동을 결정짓는 지하매질의 수리특성에 대한 불확실성을 정량화하기 위한 도구로써, 매개변수 보정법의 하나인 Pilot Point Method(PPM)을 소개하고자 한다. 우물 또는 관측정을 통해 관측되는 지하수의 수위는 지하매질의 특성을 반영하고 있으며, 인간이 가장 쉽게 취득할 수 있는 지하 정보에 해당한다. 지하수 수위를 이용하여 수치모형의 매개변수를 보정하게 되며, 이 때 PPM이 적용된다. Pilot points의 공간적인 분포에 따라 다양한 보정 결과가 산출될 수 있으며, 다양한 결과들을 통해 변동계수를 산정한 후 수리특성의 불확실성이 높은 지역을 나타낼 수 있다. 본 연구를 통해 얻은 결과는 물리탐사 또는 시추 작업을 위한 위치 선정의 기초자료로 활용될 수 있다.

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Development of An Evaluation System for the Interim Check of Integrated Rural Village Development Project (농촌마을종합개발사업 중간 점검을 위한 평가지표 적용사례)

  • Han, Kyung-Soo;Kim, Ki-Hyun;Jun, Teak-Ki;Um, Dae-Ho;Choi, Youn-Sang
    • Journal of Korean Society of Rural Planning
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    • v.13 no.2
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    • pp.121-132
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    • 2007
  • In this study, We developed an evaluation system for the interim check of Integrated Rural Village Development Project and analyzed its applicability to an actual evaluation process through a pilot evaluation on regions selected. The evaluation system consists of documentary assessments(30%) and field inspections(70%). The documentary assessments are quantitative assessments on check-lists reports by self-evaluation prepared by local governments. The field inspections are qualitative assessments by evaluation teams. Sixteen evaluation indices were developed for documentary assessments and seven criteria were designed for field inspections. For a pilot evaluation, one region in each province excluding Jeju Do, eight regions was selected and the field inspections due to circumstances was proceeded in two regions. The results of documentary assessments indicate that most of regions are evaluated low in project performance attributable to the delay in security for sites. In the field inspections, it appears that most of the regions evaluated high at the documentary assessments got a high point from them. They also show that coordination of action plans, rather than quantitative achievements, is a base determining success of the projects.

The Effects of Gabapentin in Treatment of Burning Mouth Syndrome: Retrospective Pilot Study

  • Heo, Jun-Young;Ok, Soo-Min;Jeong, Sung-Hee;Kim, Kyung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.39 no.3
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    • pp.96-99
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    • 2014
  • Purpose: The objective of this retrospective pilot study was to evaluate the effectiveness of Gabapentin in patients with primary burning mouth syndrome (BMS). Methods: Ten subjects were diagnosed with primary BMS (8 women and 2 men). The mean age was 60.1 years. They had clinical examination to exclude local factors such as the presence of Candida species, xerostomia, lichen planus, etc. They also underwent hematological examination to exclude secondary BMS due to systemic disorders. Pain was assessed by patients on an 11-point numerical rating score system (0 to 10). Gabapentin was administered at a starting dose of 300 mg/day, slowly titrated up to maximum of 1,800 mg/day. All patients were treated for 4 weeks. Results: One half of the patients (n=5) obtained reduction in pain over the treatment period. Four patients reported no reduction in pain symptoms. One patient reported that symptoms were worsening. The average pain score before the treatment was 6.3 and after the treatment was 5.25. No significant relationship was detected between pretreatment and posttreatment pain score. Only one patient noted mild side effect (dizziness). Conclusions: This retrospective pilot study provides no preliminary evidence that Gabapentin has effect in the management of BMS. However, further research (well-designed, randomized, and controlled trial with large sample) would be needed to investigate the efficacy of Gabapentin in treatment of BMS.

An Empirical Study on the Improvement of Marine Traffic System at the Pyeong-taek Adjacent Areas (평택항 접근수역의 해상교통시스템 개선에 관한 실증적 연구)

  • Yoon, Byoung-Won;Park, Jin-Soo;Park, Young-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.5
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    • pp.507-514
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    • 2015
  • This study focused on the investigating of the improving measure of marine traffic system around Pyung-Taek Pilotage area. First, we analyzed the marine traffic environment on the study area based on the expert point of view of pilot and shipmasters. Then suggested the following countermeasures to improve the traffic safety according to the analytic results of the hazardous items on the Jangan-Seo and Ippa pilot embarking/disembarking area. We suggested to establish Mokdeok-do TSS and TSS in Ando area, and to adjust the width of Jangan-seo TSS to improve the congestion on the TSSs. Also suggest to put lightbuoys along the outer limit of the TSS. In addition, recommend to establish traffic safety specific area on the Jangan-seo/Ippa-do water, and to suggest expand the anchorage area of Ippa and Jangan-seo anchorage. It is anticipated to improve the traffic safety on the study area through the marine traffic system improvements.

The Study of Infertility Stress of Female Participating in Korean Medicine Pilot Program for Subfertility (난임한방진료시범사업에 참가한 여성의 스트레스 양상에 대한 연구)

  • Ahn, In-Suk;Kim, Dong-Il
    • The Journal of Korean Obstetrics and Gynecology
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    • v.30 no.1
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    • pp.56-67
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    • 2017
  • Objectives: The purpose of this study is to elucidate infertility women's experience in psychological stress and to suggest effective infertility stress management methods. Methods: Twenty five infertility women who participate in Korean Medicine Pilot Project for Infertility completed questionnaires and Infertility Stress Scale, also, we have interviewed. Results: The Mean degree of stress of the infertile women was 2.24 point with Infertility Stress Scale. In focused interview, the infertility stress was considered to be within the aspects of intra and interpersonal. In regards to intrapersonal aspect, infertility women described the grief with lowered self-esteem and anxiety with obsession for fertility. As for the interpersonal aspect, infertility women were distressed by the relationship with spouse and in-laws, as well as friend and the public. Conclusions: Doctors in infertility clinic need to consider infertility stress of their patients and conduct effective intervention.