• 대한인간공학회지
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• 제30권1호
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• pp.117-125
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• 2011

While human error happens repeatedly in the semiconductor industry in Korea, which has brought a tremendous loss from manpower, welfare etc., there are limitations to human error prevention activities. When a semiconductor company introduces new machines and facilities from Japan or Germany, the companies often do not consider human factors in the design. Also, semiconductor companies are so occupied with promoting increased productivity, their attention to human errors has been pushed aside. Negative aspects of technical exchange associated with safety management are one aspect of the industry's nature. A semiconductor company recently began acknowledging on the back of TQM(Total Quality Management) that human error has a decisive effect on the safety. There are a number of uncontrollable and hard to handle event sets because the nature of these events with a human error may often be threatened or very intensive. It is strongly required that systemic studies should be performed to grasp the whole picture of a current situation for hazard factors. This study aims to examine the human error approach through the case of human error prevention field activities in a semiconductor industry compared with the activities and experience in nuclear power plants.

• ETRI Journal
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• 제29권5호
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• pp.569-595
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• 2007

Particularly in wireless communications, link errors severely affect the quality of the services due to the high error probability and the specific error characteristics (burst errors) in the radio access part of the network. In this work, we show that thorough analysis and appropriate modeling of radio-link error behavior are essential to evaluate and optimize higher layer protocols and services. They are also the basis for finding network-aware cross-layer processing algorithms which are capable of exploiting the specific properties of the link error statistics, such as predictability. This document presents the analysis of the radio link errors based on measurements in live Universal Mobile Telecommunication System (UMTS) radio access networks as well as new link error models originating from that analysis. It is shown that the knowledge of the specific link error characteristics leads to significant improvements in the quality of streamed video by applying the proposed novel network- and content-aware cross-layer scheduling algorithms. Although based on live UMTS network experience, many of the conclusions in this work are of general validity and are not limited to UMTS only.

• 아태비즈니스연구
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• 제13권4호
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• pp.163-175
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• 2022

Purpose - This study introduces a methodology for finding the optimal tracking error of active stock funds. Tracking error is commonly used in risk budgeting techniques as a concept of cost for alpha creation. Design/methodology/approach - This study uses a post-optimal smart beta portfolio that maximizes alpha under the given tracking error constraint. Findings - As a result of the analysis, the smart beta strategy that maximized alpha under the constraint of 0.15% daily tracking error shows the highest IR. This means the maximum theoretically achievable efficiency. In this regard, a fixed-effect panel regression analysis is conducted to evaluate the active efficiency of domestic stock funds. In addition to control variables based on previous studies, the effect of tracking error on alpha is analyzed. The alpha used in this model is calculated using the smart beta portfolio according to the size of the constraint of the tracking error as a benchmark. Contrary to theoretical estimates, in Korea, the alpha performance is maximized under a daily tracking error of 0.1%. This indicates that the active efficiency of domestic equity funds is lower than the theoretical maximum. Research implications or Originality - Based on this study, it is expected that it can be used for active risk management of pension funds and performance evaluation of active strategies.

• 대한인간공학회지
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• 제31권1호
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• pp.261-269
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• 2012

Objective: The aim of this study is to develop an analysis method to extract plausible types of errors when using a smart mobile in nuclear power plants. Background: Smart mobiles such as a smart-phone and a tablet computer(smart-pad) are to be introduced to the various industries. Nuclear power plant like APR1400 already adopted many up-to-date digital devices within its main control room. With this trend, various types of smart mobiles will be inevitably introduced to the nuclear field in the near future. However nuclear power plants(NPPs) should be managed considering a big risk as a result of the trend not only economically but also socially compared to the other industrial systems. It is formally required to make sure to reasonably prevent the all hazards due to the introduction of new technologies and devices before the application to the specific tasks in nuclear power plants. Method: We define interaction segments(IS) as a main architect of interaction description, and enumerate all plausible error segments(ES) for a part of design evaluation of digital devices. Results: We identify various types of interaction errors which are coped with reasonably by interaction design using smart mobiles. Conclusion: According to the application result of the proposed method, we conclude that the proposed method can be utilized to specify the requirements to the human error hazards in digital devices, and to conduct a human factors review during the design of digital devices. Application: The proposed method can be applied to predict the human errors of the tasks related to the digital devices; therefore we can ensure the safety to apply the digital devices to be introduced to NPPs.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1797-1802
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• 2005

In this study, we were developed an accuracy of the proposed two dimensional statical inclinometer what used a position sensitive detector(PSD) by an error analysis. The inclinometer consists of a laser source, a mass, an optic-fiber, and a PSD. The gravity direction on a base platform of the inclinometer is changed by an unknown inclination angle. And a laser spot is moved from the origin to another position of a PSD following a variation of an optical path by the gravity. These processes enable the inclinometer to estimate the inclination angle from distance information of the moving spot. A design methodology on the basis of a sensitivity analysis was applied to improve the measurement performance such as a full measuring range and a resolution. But it still has error factors, so we analyze the uncertainty of the inclinometer to evaluate the systematic errors from alignments, assembly error and so on. The experimental performance evaluation about the design objectives as a measuring range and a resolution was performed. And the validity and the feasibility of the design process were certified by an experimental process. Systematic errors eliminated to improve the accuracy of the inclinometer by the corrected measuring model from the calibration process between the inclination angle and the PSD position instead of the nominal measuring model. The ANOVA(analysis of variance) confirmed the effect of eliminating the systematic errors in the inclinometer. From these methodologies, the proposed inclinometer was able to measure with a high resolution(35.14sec) and a wide range(from $-15^{\circ}\;to\;15^{\circ}$

• 한국통신학회논문지
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• 제23권4호
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• pp.1100-1112
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• 1998

본 연구에서 망동기 시스템의 동기 기준 클럭과 시스템 클럭간에 발생하는 위상 오차를 최소화하기 위한 새로운 위상 오차 검출방식이 제안되었고 이 방식을 디지털 처리 위상 동기 루프(digital processing phase locked loop:DP-PLL) 시스템에 적용하였다. 두 클럭간에 발생하는 위상 오차는 지연된 n-탭 상승 에지 클럭으로 구성한 위상 오차 검출기에 의해 위상 오차 변이 (PEV:Phase Error Variation)로 출력된다. 위상 오차 변이는 5ns해상도로 검출되며 검출된 위상 오차 변이는 알고리즘에 의해 최적의 D/A변환기 계수를 추적하면서 위상 동기를 유지한다. 실험결과 위상 검출기는 빠르고 정확한 위상 추적 특성을 갖고 있으며 루프제어 알고리즘은 우수한 지터 억압 특성을 나타내었다.

• 전기전자학회논문지
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• 제28권1호
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• pp.116-122
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• 2024

AMBA AHB-Lite 버스는 저전력 및 경제성 측면에서 SoC에 널리 사용되는 온칩 버스 프로토콜이다. 하지만 이 프로토콜은 종단간 데이터 무결성을 위한 에러 검출 및 정정이 불가능하다. 이로 인해 자동차와 같이 열악한 환경에서 동작하는 경우에 데이터 변질과 시스템 불안정을 일으킬 수 있다. 이러한 문제를 해결하기 위해 본 논문에서는 AMBA AHB-Lite 버스에 SEC-DED(Single Error Correction-Double Error Detection)를 적용하는 방법을 제안한다. 이는 전송 중 발생하는 데이터 에러를 실시간으로 감지하고 정정하여 종단간 데이터 무결성을 강화한다. 시뮬레이션 결과, 에러가 일어나도 실시간으로 이를 감지하고 정정하여 차량용 온칩 버스에서 종단간 데이터 무결성을 강화하는 것을 확인하였다.

• 대한전자공학회논문지TC
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• 제41권10호
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• pp.45-52
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• 2004

본 논문에서는 에러 예측회로를 사용하여 연집에러 입력시 성능저하를 보완한 경판정 비터비 디코더를 제안하였다. 비터비 디코더는 최대유사복호 알고리즘을 사용하므로 랜덤에러 입력시 정정능력이 뛰어나다. 반면에 연집에러 입력시 에러 정정능력이 매우 떨어지는 단점이 있다. 제안하는 에러 예측회로는 비터비 디코더의 연집에러에 대한 에러 정정특성을 향상시키는 기능으로 비터비 디코더에 에러가 입력됨에 따라 path metric값이 증가하는 것을 이용한다. Path metric의 최대값 증가량을 이용하여 연집에러 구간을 예측, 연집에러 구간에 대한 확률 값을 줄여준다. 제안된 알고리즘을 OFDM방식의 IEEE802.11a WLAN에 적용한 비터비 디코더는 AWGN채널에서는 기존의 비터비 디코더와 동일한 성능을 유지하며, 무선 채널 환경인 다중경로 페이딩 채널에서 발생할 수 있는 연집에러에 대하여 15% 개선된 성능을 보였다.

• 한국BIM학회 논문집
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• 제6권2호
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• pp.47-57
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• 2016

Recently, the introduction and spread of BIM technology has been actively promoted at the domestic level and abroad. However, the BIM adoption and diffusion rate in the whole construction industry has been slower than expected, this is because they applied to construction projects in a way that does not meet the basic objective of BIM adoption. The objective of this paper is to derive a BIM adoption strategy that can provide benefits and efficiency from the design phase, by analyzing issues related to design errors identified in two real world projects based on the 2D to BIM conversion process. Types of issues, type distribution, and degree of BIM contribution to find issues were analyzed in a quantitative way, and then a BIM adoption strategy was derived. As a result, this paper identified that there obviously exists a limit in the 2D to BIM conversion process by repeating the problems that occur in the traditional 2D design process. Therefore, the authors of this paper insist that the design firms should adopt BIM-based design processes, fully, to get financial benefits as well as to improve the design quality.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.286-289
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• 2003

턴키공사는 설계를 도급자가 하기 때문에 설계오류로 인한 공사금액의 증액은 없다. 따라서 설계오류로 인한 공사비의 증가는 도급자의 원가율을 상승시키는 결과를 초래하고 그로인한 도급자의 채산성은 감소할 수 밖에 없는 실정이다. 또한 설계오류는 설계변경의 기간만큼 공정을 지연시키고 오류를 인식하지 못하는 경우 심각한 품질문제를 야기 시킬 수 있다. 본 연구에서는 턴키공사의 설계오류 원인을 조사하여 설계오류를 감소시킬 수 있는 방안을 제시함으로써 설계오류로 인한 원가율 상승과 공정지연, 품질저하의 문제점을 해소하고자 한다.