• 한국안전학회지
• /
• 제39권1호
• /
• pp.104-113
• /
• 2024

Unlike in general manufacturing process, safety management in laboratory-based research area is complicated because the latter generally involves trying untested methods or handling unusual substances in small amounts. Laboratory accidents in South Korea have recently shown an increasing trend. Unfortunately, statistics on such accidents are not officially published by any domestic public agencies. In this study, multivariate analysis was performed on the relationships between variables to develop effective strategies for preventing laboratory accidents. A Cross-Tabulation Analysis of accident-related factors in 179 accident cases revealed that the laboratory type, accident type, and unsafe-act type are all statistically significant, whereas the unsafe condition and management factors differ with the statistical criteria. Furthermore, the results of a Multiple-Correspondence Analysis showed that accidents can be divided largely into three groups having different accident causes and injury types; this confirms the necessity of different strategies to prevent accidents of each type. The findings also reveal differences between the distribution of accident types mentioned in the accident case collection books and actual reported cases. This suggests that an official statistical system administered by a public institution would be necessary for effective prevention of laboratory accidents.

• Journal of the Korean Data and Information Science Society
• /
• 제26권4호
• /
• pp.841-856
• /
• 2015

본 연구에서 국내 13개 업종과 16개 행정구역을 대상으로 전자상거래 구매동기와 관련된 다섯 개의 양적평가속성 (거래과정단순화, 구매비용절감, 공급자와 직접접촉, 업무추진속도향상, 기타)에 대해, 유사한 속성을 지닌 업종/행정구역들을 유사성 있는 군집끼리 분류 및 세분화하고 다차원 공간상에 시각적으로 배치시켰다. 정보화통계조사 (국가통계포털, www.kosis.kr)의 일환으로 전자상거래 경험이 있는 사업체를 대상으로 자료를 조사하였다. 구매동기 평가속성을 중심으로 유사성이 강한 업종과 행정구역을 분류한 결과 각각 4개와 2개로 유형화가 가능함을 알 수 있었다. 더 나아가 다차원 척도법을 사용하여 각 군집에 속한 업종 및 행정구역의 포지셔닝을 실시한 결과, 구매과정단순화, 구매비용절감 및 공급자와 직접접촉 속성에 대해서, 업종의 도 소매업, 기타 및 제조업이, 행정구역의 서울과 경기가 우위에, 제주는 가장 열세한 위치에 놓여있다. 반면에 업무추진속도향상과 기타속성에 대해서, 업종의 기타와 단체수리 기타 개인서비스업이, 행정구역의 충북과 경남이 각각 우위에 있으며, 도 소매업, 숙박 음식점업과 대구 및 경기는 열등한 점수를 갖는 것을 알 수 있다.

• 한국문헌정보학회지
• /
• 제40권2호
• /
• pp.333-355
• /
• 2006

이 연구에서는 지적 구조 분석을 위해서 계량서지적 자료를 시각적으로 표현하는 다양한 네트워크 형성 방식에 대해서 사례와 함께 각각의 특성을 살펴보았다. 기준값 절단 방식, 최근접이웃 그래프, 최소비용 신장트리, 패스파인더 네트워크의 네 가지 네트워크 형성 방식 중에서 전체 구조와 세부 구조의 표현 능력이 모두 뛰어난 패스파인더 네트워크 알고리즘이 최근 가장 활발히 응용되고 있다. 최근접이웃 그래프는 아직까지 계량서지적 분석에 응용된 사례는 없으나 간단한 알고리즘과 클러스터링 능력 등과 같은 지적 구조 규명에 도움이 될 수 있는 몇 가지 장점을 갖추고 있는 것으로 확인되었다. 다차원척도나 군집분석과 달리 네트워크를 이용한 시각화에서는 입력자료의 전처리에 따라서 생성된 지적 구조의 차이가 큰 것으로 나타났다. 이 연구에서 고찰한 여러 네트워크 형성 방식을 적절히 활용함으로써 국내의 지적 구조 규명 연구를 활성화할 수 있을 것이라 기대된다.

• Asia pacific journal of information systems
• /
• 제9권3호
• /
• pp.159-175
• /
• 1999

For the past decade, although there have been many studies which examined factors influencing the extent of EDI systems implementation, it is very hard to find out studies which directly investigated what the effectiveness of EDI systems are, and which factors contribute to the successful implementation of EDI systems. In this regard, this research aims to explore for the factors which constitute the effectiveness of EDI systems as perceived, based on a survey from 202 companies. The major steps of the current research are as follows. First, in order to identify important factors constituting the effectiveness of EDI systems, previous research related to the effectiveness of EDI systems was reviewed and analyzed. Second, individual items which can be considered as candidates to represent the effectiveness of EDI systems were derived from this previous research review, and a survey questionnaire was developed using those derived items. Based on the developed survey questionnaire, a pretest was administered at several domestic business firms with experiences of EDI systems. Third, survey questionnaires were distributed to and collected from the 202 companies which experienced EDI implementation. Accordingly, this research derived out five factors constituting the effectiveness of EDI systems from the result of a multivariate data analysis: strategic advantage, time reduction in business process, accuracy improvement, cost reduction, and improvement of business process quality. It was also interesting to find that the factors of EDI effectiveness are divided into three levels, similarly to three levels of the Anthony's hierarchical model of organization(Anthony, 1965): strategic, managerial, and operational levels. Furthermore, from the levels of derived factors, we developed a conceptual model which explains the possible causal relations of those factors in a hierarchical manner.

• 한국조경학회지
• /
• 제29권2호
• /
• pp.22-31
• /
• 2001

The purpose of this paper is to investigate in resources of natural recreation forest(RNRF) developed both publicly and privately in order to answer the research question: what are the differences in RNRF development between public and private developers. After reviewing the literature, the developer´s decision-making and motivation of investment, and the planning process of natural recreation forest, We constructed the conceptual framework and have formulated the hypothesis of this research. We had obtained data through a questionnaire, which surveyed of 625 visitors at 9 of the 72 natural recreation forests in Korea in 1999, We have analyzed the data using the mean difference test and logistic regression method. We found that 1) the overall quality of resource elements in RNRF has been development excellent except for the sociocultural element of recreational resources, and public recreation forest have been of higher quality than that fo private development, 20 in bivariate analysis, all the variables on quality of RNRF by public developers have turned out to be better than those of private ones, 3) in multivariate analysis, such variable as valley and water, forest and wildness area, wild life, and landscape have been statistically significant at one percent level, 4) the higher the value of valley and water, the higher the probability of public development, while the higher the value of other variables excluding water and valley, the more likelihood the recreational forest is developed by a private developer, and 5) forest and wildness area has been turned out to be the most important independent variable in contributing to the value of dependent variable. The research results suggest that 1) the differences in the quality of resource elements in RNRF developed by public and private body be considered in the planning and design process in order to develop diverse activities to make use of the resource potential, and 2) considering the resource characteristics of private natural recreation forest and the motivation of private developers, private natural recreation forest will possibly be more dynamic and dynamic attractive areas. It is recommended that the difference in the degree of visitor´s satisfaction between public and private development be examined.

• 제어로봇시스템학회논문지
• /
• 제22권4호
• /
• pp.276-280
• /
• 2016

Due to the increasing interest in safety and consistent product quality over a past few decades, demand for effective quality monitoring and safe operation in the modern industry has propelled research into statistical based fault detection and diagnosis methods. This paper describes the application of Hotelling $T^2$ index based Principal Component Analysis (PCA) method for fault detection and diagnosis in industrial processes. Multivariate statistical process control techniques are now widely used for performance monitoring and fault detection. Conventional methods such as PCA are suitable only for steady state processes. These conventional projection methods causes false alarms or missing data for the systems with transient values of processes. These issues significantly compromise the reliability of the monitoring systems. In this paper, a reliable method is used to overcome false alarms occur due to varying process conditions and missing data problems in transient states. This monitoring method is implemented and validated experimentally along with matlab. Experimental results proved the credibility of this fault detection method for both the steady state and transient operations.

• 한국산학기술학회논문지
• /
• 제20권8호
• /
• pp.216-223
• /
• 2019

생산 공정에서 발생되는 공정 이상을 적시에 감지하는 것은 생산 공정의 안전하고 일관된 조업 및 운영에 필수적인 요소 중 하나로서 반드시 필요하다. 예측되지 못하거나 적절하게 감지되지 못한 공정 이상은 전체 생산 공정과 공정에서 생산되는 최종 제품의 품질에 심각한 영향을 줄 수 있기 때문이다. 또한 이러한 상황은 공정 기능 불량과 고장으로 이어지게 된다. 이러한 공정 이상을 신뢰성 있게 적시에 검출하기 위해 본 연구에서는 새로운 단일 클래스 분류에 기반한 공정 이상 감지 기법을 제안한다. 본 연구의 제안된 방법은 잡음 필터링, 특징 선택, 비선형 표현 및 특이치 검출의 네단계로 구성된다. 본 연구에서는 시뮬레이션 공정의 측정치를 활용하여 제안된 방법의 성능을 평가하였다. 그 결과 제안된 공정 이상 탐지 기법이 신뢰할 수 있는 모니터링 결과를 산출하였으며 기존 비교 대상 방법들보다 평균 25.4% 향상된 성능을 보여 주었다. 또한 적합한 특징 선택을 통하여 보다 향상된 이상 감지 성능을 얻을 수 있었다.

• 대한간호학회지
• /
• 제49권3호
• /
• pp.329-339
• /
• 2019

Purpose: The purpose of this study was to investigate the frequency, patterns, and factors of reversals in decisions about life-sustaining treatment (LST) among older patients with terminal-stage chronic cardiopulmonary disease. Methods: This was a retrospective correlational descriptive study based on medical chart review. De-identified patient electronic medical record data were collected from 124 deceased older patients with terminal-stage cardiopulmonary disease who had made reversals of LST decisions in an academic tertiary hospital in 2015. Data were extracted about the reversed LST decisions, LST treatments applied before death, and patients' demographic and clinical factors. Multivariate logistic regression analysis was used to identify the factors associated with the reversal to higher intensity of LST treatment. Results: The use of inotropic agents was the most frequently reversed LST treatment, followed by cardiopulmonary resuscitation, intubation, ventilator therapy, and hemodialysis. Inconsistency between the last LST decisions and actual treatments occurred most often in hemodialysis. One-third of the reversals in LST decisions were made toward higher intensity of LST treatment. Patients who had lung diseases (vs. heart diseases); were single, divorced, or bereaved (vs. married); and had an acquaintance as a primary decision maker (vs. the patients themselves) were significantly more likely to reverse the LST decisions to higher intensity of LST treatment. Conclusion: This study demonstrated the complex and turmoil situation of the LST decision-making process among older patients with terminal-stage cardiopulmonary disease and suggests the importance of support for patients and families in their LST decision-making process.

• Journal of Korean Neurosurgical Society
• /
• 제64권4호
• /
• pp.524-533
• /
• 2021

Objective : When treating high-positioned anterior communicating artery (ACoA) aneurysms, pterional-transsylvian and interhemispheric approaches are both viable options, yet comparative studies of these two surgical approaches are rare. Accordingly, this retrospective study investigated the surgical results of both approaches. Methods : Twenty-four patients underwent a pterional approach (n=11) or interhemispheric approach (n=13), including a unilateral low anterior interhemispheric approach or bifrontal interhemispheric approach, for high-positioned ACoA aneurysms with an aneurysm dome height >15 mm and aneurysm neck height >10 mm both measured from the level of the anterior clinoid process. The clinical and radiological data were reviewed to investigate the surgical results and risk factors of incomplete clipping. Results : The pterional patient group showed a significantly higher incidence of incomplete clipping than the interhemispheric patient group (p=0.031). Four patients (36.4%) who underwent a pterional approach showed a postclipping aneurysm remnant, whereas all the patients who experienced an interhemispheric approach showed complete clipping. In one case, the aneurysm remnant was obliterated by coiling, while follow-up of the other three cases showed the remnants remained limited to the aneurysm base. A multivariate analysis revealed that a pterional approach for a large aneurysm with a diameter >8 mm presented a statistically significant risk factor for incomplete clipping. Conclusion : For high-positioned ACoA aneurysms with a dome height >15 mm and neck height >10 mm above the level of the anterior clinoid process, a large aneurysm with a diameter >8 mm can be clipped more completely via an interhemispheric approach than via a pterional approach.

• Journal of Preventive Medicine and Public Health
• /
• 제54권6호
• /
• pp.385-394
• /
• 2021

Objectives: This study aimed to explore the status of regional variations in acute ischemic stroke (AIS) treatment and investigate the association between the presence of a thrombectomy-capable stroke center (TSC) and the case fatality rate (CFR) of AIS within hospital service areas (HSAs). Methods: This observational cross-sectional study analyzed acute stroke quality assessment program data from 262 hospitals between 2013 and 2016. TSCs were defined according to the criteria of the Joint Commission. In total, 64 HSAs were identified based on the addresses of hospitals. We analyzed the effects of structure factors, process factors, and the presence of a TSC on the CFR of AIS using multivariate logistic regression. Results: Among 262 hospitals, 31 hospitals met the definition of a TSC. Of the 64 HSAs, only 20 had a TSC. At hospitals, the presence of a stroke unit, the presence of stroke specialists, and the rate of endovascular thrombectomy (EVT) treatment were associated with reductions in the CFR. In HSAs, the rate of EVT treatment (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.97 to 0.99) and the presence of a TSC (OR, 0.93; 95% CI, 0.88 to 0.99) significantly reduced the CFR of AIS. Conclusions: The presence of a TSC within an HSA, corresponding to structure and process factors related to the quality of care, contributed significantly to lowering the CFR of AIS. The CFR also declined as the rate of treatment increased. This study highlights the importance of TSCs in the development of an acute stroke care system in Korea.