• 아태비즈니스연구
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• 제13권3호
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• pp.281-291
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• 2022

Purpose - We study whether the bullwhip effect is prevalent among Korean firms and how the characteristics of it differ from the ones in other countries. Design/methodology/approach - We obtained quarterly financial and operational information on KOSPI-listed firms in manufacturing, wholesale, and retail industries from 2013 to 2019. We explore the variation of the bullwhip effect across firms and validate hypotheses. Findings - First, we find that for the KOSPI-listed firms, the bullwhip effect is more prevalent compared with the production smoothing. We provide additional findings by using sub-samples of manufacturing firms, wholesaling and retailing firms, big-sized firms, small- and medium-sized firms, domestic-sales intensive firms, and export intensive firms. Second, we show that in general, the bullwhip effect of Korean firms increases with the days in inventory or the demand seasonality ratio. However, the persistence of demand shock does not affect the bullwhip effect of Korean firms. Research implications or Originality - We compare our results with those in other studies that use information on the U.S. and Chinese firms. Our findings show that factors explaining the bullwhip effect across Korean firms have similarities and differences compared with firms in the U.S. and Chinese firms.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.47-51
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• 2013

Existing buildings now represent the greatest opportunity to improve building energy efficiency. Building performance analysis is becoming increasingly important because decision makers can have a better visualization of their building's performance and quickly make the solution for improving building energy efficiency and reducing environmental impacts. Nowadays, building information models (BIMs) have been widely created during the design phase of new buildings, and it can be easily imported to third party software to conduct various analyses. However, a BIM is not always available for all existing buildings. Even if a BIM is available during the design and construction phases, it is very challenging to keep updating it while a building is aged. A manual process to create or update a BIM is very time consuming and labor intensive. A laser scanning technology has been a popular tool to create as-is BIM. However it still needs labor-intensive manual processes to create a BIM out of point clouds. This paper introduces automatic as-is simplified BIM creation from point clouds for energy simulations. A framework of decision support system that can assist decision makers on retrofits for existing buildings is introduced as well. A case study on a residential house was tested in this study to validate the proposed framework, and the technical feasibility of the developed system was positively demonstrated.

• 대한안전경영과학회지
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• 제26권2호
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• pp.87-92
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• 2024

This study aims to compare six observational methods for assessing arm- and hand-intensive tasks, based on literature review. The comparison was conducted in viewpoints of body regions, force/external load, motion repetition, other factors including static posture, coupling, duration/break, pace, temperature, precision task, and final risk or exposure level. The number of risk factors assessed was more, and assessment procedure was more complex than the observational methods for assessing whole-body postural loads such as Ovako Working Posture Analysis System(OWAS), Rapid Upper Limb Assessment(RULA), and Rapid Entire Body Assessment(REBA). Due to these, the intra- and inter-reliabilities were not high. A past study showed that while Hand Arm Risk Assessment Method(HARM) identified the smallest proportion of the work tasks as high risk, Strain Index(SI) and Quick Exposure Check(QEC) hand/wrist were the most rigorous with classifying most work tasks as high risk. This study showed that depending on the observational technique compared, the evaluation factors, risk or exposure level, and evaluation results were different, making it necessary to select a technique appropriate for the characteristics of the work being assessed.

• 한국멀티미디어학회논문지
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• 제6권7호
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• pp.1266-1276
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• 2003

인터넷 환경에서는 일반 정보에 비해 수십 배 또는 수백 배가 큰 음성과 영상을 포함한 멀티미디어 정보가 전송된다. 네트워크 관리를 위한 분석 유형들은 실시간 분석, 기본분석과 심화분석으로 구성되며, 심화분석은 특정 object들에 대해 일정기간 주기 적으로 경향정보를 수집하여 네트워크 상태를 분석하는데 유용하다. 심화분석 용 경향정보 수집을 위해 SNMP 적용 시 관리자의 폴링에 대해 에이전트가 매번 응답해야 하기 때문에 네트워크 부하 증가, 응답시간 지연, 데이터 수집의 정확성 감소를 초래한다. 본 논문에서는 기존 SNMP PDU에 시간변수를 추가하여 심화분석 시에 관리자와 에이전트간 불필요한 트래픽 발생을 최소화하고, 보다 정확하게 경향정보를 수집할 수 있는 효율적인 방안을 제안하고 구현하였다. 시험 분석 결과 기존 SNMP와 호환성을 유지하면서 네트워크 트래픽 부하가 감소하였으며, 정보수집의 정확도가 증가하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7359-7366
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• 2013

Objective: To assess the effects of perioperative comprehensive supportive care interventions on outcome of Chinese esophageal cancer patients in a prospective study. Methods: 60 patients with primary esophageal carcinoma were randomized into an intervention group (IG, n=31) and a control group (CG, n=29). The Chinese version of symptom checklist-90 (SCL-90) was adopted to assess their psychological status. The interventions, including health education, psychological support, stress management, coping strategies and behavior training, were carried out in 3 phases (preoperative, postoperative I and postoperative II), and psychological effects were thereafter evaluated accordingly before surgery, and 1 week, 4 weeks and 24 weeks post-surgery. Medical costs were estimated at discharge. Survival of patients was estimated each year post-surgery. General health status and satisfaction-with-hospital were surveyed by a follow-up questionnaire 4 years post-surgery. Results: All the subjects demonstrated higher scores in the preoperative phase than the normal range of Chinese population concerning 7 psychological domains including somatization, obsessive-compulsive, depression, anxiety, hostility, phobic anxiety and paranoid ideation. Although no significant difference was observed between the two groups at admission, the scores of IG, which tended to decrease at a faster rate, were generally lower than those of CG at weeks 1, 4 and 24 post-surgery. The length of hospital stay and medical costs of IG were significantly less than those of CG and satisfaction-with-hospital was better. However, there was no significant difference in 4-year survival or health status between two groups. Conclusions: Appropriate perioperative comprehensive supportive care interventions help to improve the psychological state of Chinese patients with esophageal carcinoma, to reduce health care costs and to promote satisfaction of patients and their families with hospital.

• 한국물환경학회지
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• 제25권1호
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• pp.102-111
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• 2009

Turbid storm runoff from intensive highland agriculture area has emerged as the major problem of water quality deterioration in the upstream region of the Han River. High slope of the upland combined with high rate of fertilization and intensive plowing causes high rate of soil erosion, and subsequently high suspended sediment and phosphorus content in the runoff water. The variations of water quality during rain spells were surveyed for two years (2005 and 2006) in the Jawoon Stream that is one of hot spots of intensive horticulture discharging turbid storm runoff. SS and TP showed large increase according to the increase of flow rate, whereas TN and BOD showed less fluctuations. Mean EMCs of SS and TP measured for nine rain events were as high as $207mgSS{\cdot}L^{-1}$ and $0.27mgP{\cdot}L^{-1}$, respectively. The export coefficient of SS and TP per area of cultivated field were calculated as $11,912kgSS{\cdot}yr^{-1}{\cdot}km^{-2}$ and $785kgP{\cdot}yr^{-1}{\cdot}km^{-2}$, repectively, which are significantly higher than reports of other area. It can be concluded that SS and TP in the runoffs were high enough to impose major threat to aquatic habitats, and the highland agriculture should be the main target of water quality management or habitat conservation in the study area.

• 디지털융복합연구
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• 제18권9호
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• pp.229-237
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• 2020

본 연구의 목적은 중환자실 간호사의 도덕적 민감성과 셀프리더십, 피로도 및 표준주의지침 수행도의 상관관계를 파악하고 표준주의지침 수행도에 미치는 영향요인을 탐색하기 위함이다. 연구대상은 전국 의료기관의 중환자실 네트워크를 활용하여 15개 종합병원 중환자실 간호사 153명을 대상으로 하였으며, 자료수집은 2019년 3월 5일부터 2019년 3월 10일까지 시행하였다. 자료분석은 Descriptive statistics, Pearson's correlation coefficient, Stepwise multiple regression analysis를 이용하였다. 연구결과, 본 연구대상자의 표준주의지침 수행도에 셀프리더십(r=.17, p=.042)이 통계적으로 유의한 양의 상관관계를 보였다. 연구대상자의 표준주의지침 수행도에 영향을 주는 요인을 확인하기 위하여 단계적 회귀분석을 수행한 결과, 셀프리더십(β=.17, p=.042)이 유의한 요인으로 나타났으며, 설명력은 통계적으로 유의하였다(R²=.03, F=4.21, p=.042). 따라서 최근 간호사의 높은 수준의 표준주의지침 수행도를 유지하게 된 시점에 각 병원은 간호사들의 셀프리더십 역량 강화를 위한 노력이 필요하다.

• 대한임상독성학회지
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• 제3권2호
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• pp.86-92
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• 2005

Purpose: The main cause of death due to acute organophosphate (OP) poisoning is believed acute respiratory failure caused by cholinergic reactions. Recently, advances in respiratory and intensive care make it possible to maintain the respiratory function of patients with OP poisoning, but the mortality rates remain high. The present study clarified the hemodynamics of patients with acute lethal OP poisoning. The purpose of this study was to analyse the outcomes and predictors of mortality in patients with acute OP poisoning requiring intensive care. Methods: We reviewed medical and intensive care records of patients with acute OP poisoning admitted to emergency department and ICU between March 1998 and Aug 2005. We collected patient information regarding poisoning, clinical, and demographic features. Results: During the study period, 67 subjects treated with intensive care and ventilator management in addition to gastric decontamination standard therapy with atropine and 2-PAM. Of 67 patients, 13 died. Kaplan-Meier survival analysis demonstrated a steep decline in the cumulative survival to $86.6\%$ during the first week. Mean arterial pressure < 60 mmHg within the first 24 hours was recognized as a poor prognostic indicators among mechanical ventilated patients. Conclusion: Most OP poisoning-related deaths occurred within the first week of poisoning. Mean arterial pressure lower than 60 mmHg might be the best predictor of poor outcome. We speculated that the refractory hypotension is the leading cause of death in patients with lethal OP poisoning that receiving mechanical ventilation and maximal supportive care.

• 실천공학교육논문지
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• 제13권2호
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• pp.243-249
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• 2021

대학 자체로 선정한 대학 고유의 핵심 6개 역량들 중에서 측정된 부족한 사항들을 강화시켜 교육 목표에 도달하기 위해, 학생 융합적 사고 역량과 자기 계발 역량을 최대화하는 집중 이수형 과목 형태로 공학 관련 전공 콜라주 과목을 신설하였다. 학부/학과간 공유형 교육과정으로 진행하였고, 2020학년 1,2학기 각각에서 2개 이수 집단(전기전자제어공학부 전자공학전공; 26명, 광공학과; 28명) 54명을 대상으로 공통된20개 문항들의 설문 결과를 종합, 분석하였다. 그 결과 응답자75% 이상이 장소와 시간에 자유로운 온라인 학습에 긍정적이었고, 녹화된 동영상 학습 시간내 추가적인 상호작용 활동들과 팀티칭(team teaching) 방식을 보강한 집중 이수 형태는 학습 효과를 극대화할 수 있다고 판단한다.

• 한국경영과학회지
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• 제18권3호
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• pp.129-149
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• 1993

The high level of activity in the development and maintenance of computer software makes the scheduling of software projects an importnat factor in reducing operating costs and increasing competitiveness. Software activity is labor intensive. Scheduling management of hours of software work is complicated by ther interdependencies between the segments of work, and the uncertainties of the work itself. This paper discusses issues of scheduling in software engineering management, and presents a modular decomposition model for software project scheduling, taking advantage of the facility for decomposition of a software project into relatively independent work segment modules. Modular decomposition makes it possible to treat scheduling as clustering and sequencing in the context of integer programming. A heuristic algorithm for the model is presented with some computational experiments.