• Geomechanics and Engineering
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• 제24권3호
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• pp.281-293
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• 2021

Uncertainties in geomechanical input parameters which mainly related to inappropriate data acquisition and estimation due to lack of sufficient calibration information, have led wellbore instability not yet to be fully understood or addressed. This paper demonstrates a workflow of employing Quantitative Risk Assessment technique, considering these uncertainties in terms of rock properties, pore pressure and in-situ stresses to makes it possible to survey not just the likelihood of accomplishing a desired level of wellbore stability at a specific mud pressure, but also the influence of the uncertainty in each input parameter on the wellbore stability. This probabilistic methodology in conjunction with Monte Carlo numerical modeling techniques was applied to a case study of a well. The response surfaces analysis provides a measure of the effects of uncertainties in each input parameter on the predicted mud pressure from three widely used failure criteria, thereby provides a key measurement for data acquisition in the future wells to reduce the uncertainty. The results pointed out that the mud pressure is tremendously sensitive to UCS and SHmax which emphasize the significance of reliable determinations of these two parameters for safe drilling. On the other hand, the predicted safe mud window from Mogi-Coulomb is the widest while the Hoek-Brown is the narrowest and comparing the anticipated collapse failures from the failure criteria and breakouts observations from caliper data, indicates that Hoek-Brown overestimate the minimum mud weight to avoid breakouts while Mogi-Coulomb criterion give better forecast according to real observations.

• 한국전자거래학회지
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• 제16권3호
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• pp.93-112
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• 2011

최근 온라인 쇼핑 활동의 증가와 함께 소비자들은 온라인상에서의 제품에 대한 리뷰를 합리적인 구매 결정을 내리기 위한 중요한 정보로 활용하고 있다. 하지만 소비자들은 많은 양의 온라인 리뷰 중 그들의 구매 결정에 유익하게 활용될 리뷰를 선택하기가 쉽지 않다. 따라서 본 연구에서는 정교화 가능성 이론(elaboration likelihood model)을 바탕으로, 유익한 온라인 소비자 리뷰를 결정하는 요인이 무엇인지 알아보고, 구매하고자 하는 제품의 가격에 따라 유익한 리뷰를 결정짓는 요인이 어떻게 변화되는지를 분석하고자 한다. 본 분석을 위해 아마존 닷컴의 75,226개의 온라인 소비자 리뷰 데이터를 수집하고, 리뷰 메시지의 감정어 분석 (sentimental analysis)을 통해 메시지 내용에 대한 정량변수도 확보하였다. 다중회귀분석 결과, 리뷰 점수, 리뷰어에 대한 랭킹 정보를 포함하는 주변적 단서(peripheral cues)와 리뷰 메시지의 단어 수, 부정어 비율의 중심적 단서(central cues) 모두 리뷰의 유익성에 영향을 미치는 것으로 나타났다. 또한, 고가격 제품과 저가격 제품에서 유익한 리뷰를 결정하는 요인이 다르게 나타남을 확인하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권2호
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• pp.43-54
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• 2013

In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed.

• The Journal of Asian Finance, Economics and Business
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• 제7권8호
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• pp.635-644
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• 2020

The construction industry in developing countries like Vietnam, which incorporates small and medium construction enterprises, is typically more prone to disputes and contract dispute-related lawsuits. A dispute may occur at any time in the life cycle of the project. It is sometimes solved with the intermediation of a lawyer or directly by stakeholders. Understanding the causes of disputes in a construction project not only improves the efficiency of a company but also increases the success of projects. This study was carried out using a questionnaire survey at construction projects in Ho Chi Minh City. Sample data with 117 observations were analyzed to find the disputing factors in construction projects: diversity of working style among the parties; reluctance to work; and poor teamwork. Correlation coefficient on a rank of factors between design consultant and contractor; Design consultant and project owners are positively correlated. The Exploratory Factor Analysis (EFA) analysis identified six groups of factors in construction disputes: cooperation, technology, economics, productivity, information, and behavior. The findings are useful for enterprise practice and provide participants with an overview of sources of dispute. Thus, a more complete risk management plan can be formulated, which will accelerate project progress and improve the likelihood of success.

• 한국도서관정보학회지
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• 제32권3호
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• pp.1-29
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• 2001

이 연구는 비영리조직이용자 불평행동의 한 예로서 공공도서관 이용자의 불평행동에 대한 포괄적인 연구로 시도된 것이다. 이 연구에서는 불평에 대한 태도와 불평비용, 불평의 성공가능성, 서비스의 중요성, 외적귀인, 충성도 등의 불평행동의 선행요인이 이용중단, 항의, 부정적 구전, 제3자를 통한 불평 등의 각 불평행동 유형에 미치는 영향을 실증적으로 분석하였다. 특히 비영리조직의 특성과 관련하여 선행요인으로 "무료이용지각"이라는 새로운 변수를 검토하였다. 서비스에 불만족한 대구지역 공공도서관의 성인이용자 515명을 대상으로 한 설문조사를 바탕으로 결과를 분석하였다.

• Archives of Reconstructive Microsurgery
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• 제26권1호
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• pp.9-13
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• 2017

Purpose: Fingertip amputations are the most common type of upper limb amputations. Composite grafting is a simple and cost-effective technique. Although many factors have investigated the success of composite grafting, the success rate is not high. Therefore, this study was conducted to investigate whether the microscopic procedure process during composite grafts improves the success rate. Materials and Methods: Thirteen cases of unreplantable fingertip amputation underwent a microscopic resection procedure for composite graft in the operating room. The principle of the procedure was to remove the least devitalized tissue, maximize the clean tissue preservation and exact trimming of the acral vessel and to remove as many foreign bodies as possible. Results: All fingertips in the thirteen patients survived completely without additional procedures. Conclusion: Composite grafting allows for the preservation of length while avoiding the donor site morbidity of locoregional flaps. Most composite grafts are performed as quickly as possible in a gross environment. However, we take noticed the microscopic resection. This process is thought to increase the survival rate for the following reasons. First, the minimal resection will maximize the junction surface area and increase serum imbibition. Second, sophisticated trimming of injured distal vessels will increase the likelihood of inosculation. Third, accurate foreign body removal will reduce the probability of infection and make it possible to increase the concentration and efficiency in a microscopic environment. Although there is a need for more research into the mechanisms, we recommend using a composite graft under the microscopic environment.

• 한국산업정보학회논문지
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• 제14권3호
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• pp.76-97
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• 2009

전략경영의 중요이슈는 전략수립, 전략실행 및 성과측정에 이르는 일련의 전력경영과정을 하나의 관리적 이론으로 통합하는데 있다. 본 논문은 파워프로세스에 기초하여 전략경영 과정을 하나의 관리적 이론으로 통합하기 위한 이론과 실천적 방안을 제시하여 전략적 성공이나 지속가능 경쟁우위에 기여하고자 한다. 이를 위하여 본 논문에서는 파워프로세스의 원리와 특성을 논의하고 이를 기반으로 전략경영의 과정의 통합을 위한 학술적 및 실천적 방안을 제시하고 있다. 또한 본 논문에서는 경쟁우위를 위한 산업구조, 자원기반 및 게임이론 접근의 가정과 경쟁적 환경 및 상대적 우위에 대해서 논의하고, 파워프로세스의 성격과 특성을 규명하여 파워프로세스에 의한 경쟁우위 접근이 이들과의 상대적 위치를 규명하였다. 파워프로세스는 경쟁우위를 위한 전략수립과 관리적 개념을 통합할 수 있는 이론적 및 경영적 방안을 제공할 뿐만 아니라 전략성공에 크게 기여할 수 있다.

• 기술혁신학회지
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• 제21권4호
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• pp.1474-1492
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• 2018

본 연구는 중소기업에 대한 정부지원의 직접효과(과제성공)와 간접효과(매출성장)를 재무적으로 어려운 한계기업과 정상기업간의 차이에 초점을 두어 실증적으로 분석하였다. 한계기업이 기술개발 역량(과제성공)에도 문제가 있고 과제 후의 자립적 방식의 경제적 회생역량(매출성장)에도 문제가 있다면, 정부재원의 효율적, 효과적 운용과 정부R&D과제의 관리측면 효율성을 위해서도 이러한 기업을 지원에서 배제하는 것이 마땅할 것이다. 만약 그렇지 않다면, 정부R&D가 자본시장의 실패를 보완하여 가능성 있는 한계기업의 회생에 도움을 주는 긍정적 역할을 수행할 수도 있을 것이다. 본 연구는 중소벤처기업부의 2013년 및 2014년 총 7개 R&D지원사업에 참여한 7,575개 수혜기업을 분석대상으로 하였다. 로지스틱 회귀분석의 결과, 한계기업의 과제성공확률은 정상기업과 차이가 없었지만, 과제 후의 매출성장경향은 정상기업보다 작다는 점을 확인하였다. 한계기업에 한해서는 정부과제에 성공한 기업이 실패한 기업보다 매출성장 경향이 더 크다는 결과도 도출하였다.

• Nuclear Engineering and Technology
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• 제29권1호
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• pp.1-6
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• 1997

This paper presents a new dynamic approach for assessing feasibility associated with the implementation of accident management strategies by the operators. This approach includes the combined use of both the concept of reliability physics and a dynamic event tree generation scheme. The reliability physics is based on the concept of a comparison between two competing variables, i.e., the requirement and the achievement parameter, while the dynamic event tree generation scheme on the continuous generation of the possible event sequences at every branch point up to the desired solution. This approach is applied to a cavity flooding strategy in a reference plant, which is to supply water into the reactor cavity using emergency fire systems in the station blackout sequence. The MAAP code and Latin Hypercube sampling technique are used to determine the uncertainty of the requirement parameter. It has been demonstrated that this combined methodology may contribute to assessing the success likelihood of the operator actions required during accidents and therefore to developing the accident management procedures.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.631-637
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• 1994

For at least 14 years after the publication of minimum permissible exposure limits that would largely eradicate industrial deafness, statute legislation in Queensland remained unchanged and ineffective. Industrial deafness continued to occur. New legislation, introduced in 1989 and amended in 1993, and based on a duty of care responsibility incumbent on all, may remedy this situation. The new legislation is examined and comments are made about the values inherent in the new approach. It is concluded that public policy strategists may increase the likelihood of success of they ensure that the duty of care provisions (together with the general provisions of the Act) are backed up by innovative complementary economic, financial and marketing incentives.