• 한국신뢰성학회지:신뢰성응용연구
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• 제18권1호
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• pp.66-71
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• 2018

Purpose: Performance recovered from SCR through cleaning was studied, measuring differential pressure, NOx reduction efficiency, fuel consumption and engine power before and after cleaning. Ideal cleaning intervals are proposed based on SCR mileage and differential pressure. SCR endurance and reliability improvements through cleaning were studied through physicochemical testing of SCR durability at 43,000km 50,000km, and 110,000km respectively. Methods: Engine power, fuel consumption and exhaust gas were measured using engine full load tests and ND-13 MODE by installing the SCR before cleaned at total engine mileages of 400,000 km, 300,000km and 200,000km. The same tests were performed after cleaning the SCR catalytic converter. Endurance and reliability of the SCR cleaning was studied through the same test by SCR catalyst after each 43,000km 50,000km, 110,000km, durability test on SCR cleaning. Conclusion: We confirmed the low-performance of the SCR due to clogging is restored by SCR cleaning technology. The NOx reduction efficiency was restored to 82%, 86% and 88% from 69%, 72% and 79%. As well as the NOx reduction efficiency, it was confirmed that the engine power, fuel consumption and back pressure was restored to fresh SCR levels. As a result of the durability and reliability achieved through SCR cleaning, we confined the appearance and reduction efficiency through visual inspection and ND-13 MODE are similar to new SCR catalysts. Finally, it was judged that there was no change in performance even when driving the SCR without cleaning throughout the 100,000 km mileage warranty.

• 한국정보통신학회논문지
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• 제20권12호
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• pp.2379-2386
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• 2016

본 연구는 최근 급성장하고 있는 모바일 쇼핑시장에서 향후 전략적 마케팅시사점을 얻고자 대학생들을 대상으로 IPA매트릭스를 활용하여 분석하였다. 모바일 쇼핑몰 선택속성에 대한 IPA분석결과는 다음과 같다. 첫째, 21개 속성 중 '제공되는 제품의 신뢰성(6.09)'이 중요도가 가장 높게 나타났으며, '대금결제의 편리성(5.29)'이 수행도가 가장 높게 나타났다. 둘째, 유지 강화가 필요한 영역(Doing great, Keep it up)에는 '대금결제의 편리성', '제공되는 제품의 신뢰성' 등 11개 속성 등이 포함되었다. 셋째, 불만족 영역(Focus here)으로서 시정노력이 필요한 속성으로는 '교환이나 반품처리 및 A/S 등을 위한 대기시간 단축'이 해당되었다. 넷째, 중요도와 수행도 모두 낮은 영역(Low Priority)에는 '푸시/알림이 구매에 도움' 등 3개 속성이 해당되었다. 다섯째, 과잉노력지양 영역(Overdone)에는 '제품종류가 다양' 등 4개 속성이 해당되었다.

• International Journal of Reliability and Applications
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• 제2권3호
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• pp.161-187
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• 2001

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms reliability, failure rate, product life, and durability are explained. From the customer's standpoint, the concept of product quality is classified in five factors, according to related technology: performance, reliability, conformance to specifications, customer perception, and fundamentals advantage. The correlation of the five factors for a first-class product is discussed, Since the market share of a company is determined as the competition result of its product value, defined as product quality and price, the market share increase is derived mathematically from the increment of product value. The market share increase, $\Delta$S, can be calculated from the present market share, S, and the oriented relative value increment of new product, R, to the current product in the same company for the same market target: $\Delta$S : $\Delta$(1-S). R/(1+S.R). Finally, the importance of separating warranty cost from the profit equation for the durables is explained.

• 무역상무연구
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• 제26권
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• pp.203-223
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• 2005

Many international transactions involve the use of security devices, commonly referred to as "guarantees", "bonds", or "standby credits", designed to protect one of the parties from a breach by its counter-party. These security mechanisms may be provided by banks, insurance companies, specialized surety companies, or other financial service firms. Although some legal systems distinguish between "guarantees", "bonds", and "indemnities", these terms are often used as synonyms in the everyday language of international traders. It may therefore be necessary to examine the particular characteristics and nature of the guarantee obligation in order to properly classify the guarantee. Two main categories of guarantee are demand and suretyship. Under a demand guarantee, the guarantor must pay on first demand by the beneficiary. The beneficiary only has to demand payment under the guarantee - there is no need to prove that the principal has actually defaulted on a contractual obligation. Under a suretyship or conditional guarantee, the obligation of the guarantor is triggered by the actual default or contractual breach of the principal, as evidenced in a document such as a court judgement or arbitral award against the principal. Guarantees have been widely used in the international business transactions. Main uses of guarantees are as follows : Performance Bonds/Guarantees, Bid(or Tender) Bonds/Guarantees, Advance Payment or Repayment Bonds/Guarantees, Retention Bonds/Guarantees, Maintenance(or Warranty) Bonds/Guarantees etc.

• 한국정보통신학회논문지
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• 제15권6호
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• pp.1381-1385
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• 2011

최근 출시되는 고사양의 Hand-phone에 적용되어진 Camera Module은 대부분 Auto Focusing기능이 탑재되어 있으며 Camera Module의 화소 수가 높아지면서 좀 더 정밀하고 안정적인 AF구동제품이 소비자에 의해 요구되고 있다. 본 논문은 현재 출시되고 있는 Camera Module적용 VCM(Actuator)의 문제점인 Auto Focusing시 Lens 초점위치 및 Module 자세에 따른 해상도편차 발생으로 해상도 보증 및 안정된 Actuator 구동을 위해 개선된 구조의 변경구조 VCM을 제안한다.

• 한국자동차공학회논문집
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• 제22권3호
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• pp.203-209
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• 2014

The rear center-hinge bracket is designed for supporting and folding the rear-seat backrest. This bracket needs to be strong enough to be able to rigidly hold the rear-seat backrest and to withstand luggage loads from the car trunk that are generated when a vehicle is driving on the roads. Particularly, current accident studies report that many serious occupant injuries occurred when the rear-seat back easily folded inward toward the car interior, driven by the luggage loads in the trunk. Given this fact, the robust design of the rear center-hinge bracket that mainly supports the rear backrest has become more important for providing customer safety and preventing high warranty and durability problems. However, none of the studies have emphasized its significant role and considered its robust optimization. Therefore, this paper presents how the hinge-bracket design is optimized based on an application of the finite-element method coupled with the parameter design using Taguchi's design experiment. Finally, Taguchi method's application optimizes a robust center-hinge bracket that shows more rigid performance although it has lighter weight and thinner thickness.

• 한국건축시공학회지
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• 제13권2호
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• pp.112-121
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• 2013

Korean overseas construction has been on the rise, and exceeded the 2011 goal of $50 billion by securing $59.1 billion in orders. However, these orders were heavily concentrated in the Middle East (50%) and plant construction contracts (75%). This study suggests that, to maintain growth in foreign markets, Korea construction companies should enter into the high value-added investment development business and aggressively seek ways to diversify their regions of activity and construction types. To secure the entry of Korean construction companies into lucrative markets and better understand the competitive factors facing Korean construction concerns, a survey of the literature and focus group discussions targeting relevant experts were carried out. From those efforts, a list of 44 competitive factors crucial to entering and competing in the international investment development business was developed. Survey responses were analyzed by applying IPA. The results revealed that while Korean concerns compete well in engineering/technical capabilities, maintaining a cooperative relationship with contractors, and warranty/after sales service capabilities, their ability to obtain business information on the target country, to form private/public cooperative systems, and to build international human networks require immediate improvement.

• 디지털콘텐츠학회 논문지
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• 제11권3호
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• pp.331-339
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• 2010

네트워크 보안에서의 효율성은 침입차단 성능과 시스템 performance로 대표된다. 네트워크 보안의 성능 향상을 위해서는 네트워크 인프라스트럭쳐에서의 기능적인 효율성을 우선 확보해야 한다. 그동안 네트워크 보안 효율성 제고 달성에 관한 많은 방법론들이 연구되었다. 이 같은 연구의 목적은 인프라스트럭쳐에서의 효율성 메커니즘 구현을 통해 빠른 응답시간내에 보다 우수한 침입차단을 실현하는 것이다. 이를 위해서 네트워크 보안 도메인 효율성 구조를 설계하고 구조별 효율성 측정방법을 연구함으로써 인프라스트럭쳐상에서의 보안방법론 모델을 제안하였다. 본 연구에서 제안한 방법론을 통해 체계적인 도메인 설계와 측정방법을 실시할 경우 운용인프라스트럭쳐 시스템상에서 보안 효율성 확보가 가능함이 입증되었다.

• 농업과학연구
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• 제47권2호
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• pp.315-326
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• 2020

In this study, a real-time crop recognition system was developed for an unmanned farm machine for upland farming. The crop recognition system was developed based on a stereo camera, and an image processing framework was proposed that consists of disparity matching, localization of crop area, and estimation of crop height with coordinate transformations. The performance was evaluated by attaching the crop recognition system to a tractor for five representative crops (cabbage, potato, sesame, radish, and soybean). The test condition was set at 3 levels of distances to the crop (100, 150, and 200 cm) and 5 levels of camera height (42, 44, 46, 48, and 50 cm). The mean relative error (MRE) was used to compare the height between the measured and estimated results. As a result, the MRE of Chinese cabbage was the lowest at 1.70%, and the MRE of soybean was the highest at 4.97%. It is considered that the MRE of the crop which has more similar distribution lower. the results showed that all crop height was estimated with less than 5% MRE. The developed crop recognition system can be applied to various agricultural machinery which enhances the accuracy of crop detection and its performance in various illumination conditions.

• 통상정보연구
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• 제18권2호
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• pp.131-150
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• 2016

최근 글로벌 무역 공급체인관리는 글로벌 비즈니스에서 국제표준인증이 파트너십을 형성하는데 중요한 요인으로 등장이 되고 있다. 글로벌 기업들은 생산과 판매를 전 세계지역에 동시에 진행하기 때문에 글로벌 파트너를 결정하는데 국제표준인증 활용이 기업의 성과에 중요한 영향을 미친다. 우리나라 수출입 제조 기업들은 국제표준인증 인증을 획득하여 글로벌 파트너십을 구축하는 노력을 기울이고 있다. 따라서 본 연구에서는 국제표준인증 활용의 전략적 수준과 운영적 수준, 파트너십 프로세스의 신뢰, 몰입, 협력 요인이 기업의 사업성과에 미치는 구조적 관계를 규명하였다. 이를 위해서 우리나라 수출입 제조기업 147개 기업을 대상으로 설문조사를 진행하였고, 구조방정식모형(Structural equation model)으로 실증분석을 실시하였다. 본 연구의 가설검증 결과 다음과 같은 연구결과를 도출하였다. 첫째, 국제표준인증 전략적 수준은 신뢰, 몰입에 긍정적인 영향을 미쳤다. 둘째, 국제표준인증 운영적 수준은 신뢰, 협력에 긍정적인 영향을 미쳤다. 셋째, 파트너십 프로세스의 신뢰는 몰입에 긍정적인 영향을 미쳤고, 몰입은 협력에 긍정적인 영향을 미쳤다. 넷째, 파트너십 프로세스의 협력은 기업의 사업성과에 긍정적인 영향을 미쳤다. 본 연구의 시사점은 기업들이 파트너십을 구축할 때 국제표준인증 활용 수준 정도에 따라 비즈니스 성과에 영향을 미친다. 기업의 사업성과를 향상시키기 위해서는 신뢰, 몰입, 협력의 파트너십 프로세스가 글로벌 무역 공급체인망 구축과 파트너십을 유지하는 주요한 요인으로 연구결과가 도출되었다.