• 대한간호학회지
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• 제16권2호
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• pp.63-69
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• 1986

The main purpose of this study was to find out variables relevant to self-care activities of physically disabled person. The subjects of this analysis were 1277 person which is between 15~64 years, the data came from the 1985 National Interview Survey on Disabled Person in Korea. For this analysis, Breakdown, Oneway and Discriminant Analysis were used. The finding of the analysis can be summarized as follows: First, the mean of self care activities was 2.57 (SD: 0.69, range: 1-3). The relevance for the self-care activities by several variables is as follows. 1. The relevance for the self-care activities by socioeconomic status is significant at age, education level, occupation of household members variables. Especially, in the case of high age, low education level, the self-care activities are shown low score. 2. The relevance by impairment characteristics is shown high significance at all input variables. When disabled person have double impairment. paralysis, late occurance age, and is due to diseases the self-care activities score is lowered. 3. The relevance by health care services variables. is not shown significant at all input variables. Second, the relevance for social activities by sev-eral variables was conducted by discriminant analysis. The relative importance of social activities discriminant function is 0.344 of eigenvalue. The-canonical correlation between the social activities discriminant function and 9 dummy variables is 0.51, total variance of dummy variables for social activities is shown 26 persent. The self-care activities variable represents the highest contribution of its associated variable to the function (canonical coefficient: -.56). The occurance age, the occupation of household members, the education level variables are shown comparatively high contribution to the function. To sum up, this analysis suggests that the self-care activities variable is the highest contributed to the social activities. In relation to self-care concept, this finding will be useful in rehabilitation nursing care.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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• pp.281-287
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• 1999

Decision class analysis (DCA) is viewed as a classification problem where a set of input data (situation-specific knowledge) and output data (a topological leveled influence diagram (ID)) is given. Situation-specific knowledge is usually given from a decision maker (DM) with the help of domain expert(s). But it is not easy for the DM to know the situation-specific knowledge of decision problem exactly. This paper presents a methodology fur sensitivity analysis of DCA under incomplete information. The purpose of sensitivity analysis in DCA is to identify the effects of incomplete situation-specific frames whose uncertainty affects the importance of each variable in the resulting model. For such a purpose, our suggested methodology consists of two procedures: generative procedure and adaptive procedure. An interactive procedure is also suggested based the sensitivity analysis to build a well-formed ID. These procedures are formally explained and illustrated with a raw material purchasing problem.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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• pp.281-287
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• 1999

Decision class analysis (DCA) is viewed as a classification problem where a set of input data (situation-specific knowledge) and output data(a topological leveled influence diagram (ID)) is given. Situation-specific knowledge is usually given from a decision maker (DM) with the help of domain expert(s). But it is not easy for the DM to know the situation-specific knowledge of decision problem exactly. This paper presents a methodology for sensitivity analysis of DCA under incomplete information. The purpose of sensitivity analysis in DCA is to identify the effects of incomplete situation-specific frames whose uncertainty affects the importance of each variable in the resulting model. For such a purpose, our suggested methodology consists of two procedures: generative procedure and adaptive procedure. An interactive procedure is also suggested based the sensitivity analysis to build a well-formed ID. These procedures are formally explained and illustrated with a raw material purchasing problem.

• 경영과정보연구
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• 제17권
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• pp.161-189
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• 2005

As the importance of intellectual assets has been brought into relief, this study aims at positively verifying where the intellectual workers' overall level of their knowledge conversion preference and their job character has reached, and how much the knowledge conversion preference, the job character and the fitness of both factors affects the job effectiveness respectively. For this purpose 3 types of research hypotheses were set up and the result of the verification of the hypotheses is summarized as follows: First, the verification of the relation between the knowledge conversion preference and the job effectiveness revealed that the workers who have the higher synthetic ability in knowledge conversion preference show the higher job satisfaction and job product. Secondly, the verification of the relation between the MPS representing the job character by measured index and the job satisfaction revealed that the absolute value of relative coefficient between the 4 factors excluding the public welfare factor and the MPS is 4, interpreted as medium correlation. Thirdly, the analysis on the degree of relation between the job product measured by the quality of job result and the input effort and the MPS showed that the absolute value of person relative coefficient is 5, interpreted not only as medium correlation but also very meaningful. Accordingly, the main purpose of this study was to give a guideline which can be utilized as an indicator for educating, training and placing the workers. As results, the main effect that the variable of knowledge conversion preference and job character chosen as the independent variable influences on the dependent variable of job satisfaction and job product is very meaningful except the public welfare factor.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.161-161
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• 2023

Bias correction of values is a necessary step in downscaling coarse and systematically biased global climate models for use in local climate change impact studies. In addition to univariate bias correction methods, many multivariate methods which correct multiple variables jointly - each with their own mathematical designs - have been developed recently. While some literature have focused on the inter-comparison of these multivariate bias correction methods, none have focused extensively on the effect of diverse configurations (i.e., different combinations of input variables to be corrected) of climate variables, particularly high-dimensional ones, on the ability of the different methods to remove biases in uni- and multivariate statistics. This study evaluates the impact of three configurations (inter-variable, inter-spatial, and full dimensional dependence configurations) on four state-of-the-art multivariate bias correction methods in a national-scale domain over South Korea using a gridded approach. An inter-comparison framework evaluating the performance of the different combinations of configurations and bias correction methods in adjusting various climate variable statistics was created. Precipitation, maximum, and minimum temperatures were corrected across 306 high-resolution (0.2°) grid cells and were evaluated. Results show improvements in most methods in correcting various statistics when implementing high-dimensional configurations. However, some instabilities were observed, likely tied to the mathematical designs of the methods, informing that some multivariate bias correction methods are incompatible with high-dimensional configurations highlighting the potential for further improvements in the field, as well as the importance of proper selection of the correction method specific to the needs of the user.

• 기술혁신학회지
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• 제19권3호
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• pp.658-685
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• 2016

기술경제이론에서는 연구개발을 통한 기술혁신이 경제성장의 핵심요소로 간주하고 있다. 본 연구는 사회학, 경영학에서 사용되고 있는 경로분석(path analysis)방법을 활용하여 연구개발 투입변수(GDP 대비 총 연구개발비 비중, 총 연구원수, 이공계 학사학위 비율)가 매개변수인 산출변수(과학기술논문수, 특허등록수)를 통해 경제적 성과변수인 GDP에 어떻게 영향을 미치는지 분석하였다. 연구개발 활동 변수 중 과학기술논문수(0.967), 총 연구원수(0.373), 총 연구개발비 비중(0.191), 특허등록수(0.049), 이공계 학사학위 비율(0.007) 순으로 GDP에 가장 큰 효과를 가지는 것으로 나타났다. 총 연구개발비 비중과 총 연구원수는 GDP에 직접효과보다 논문이나 특허를 매개로 하여 GDP에 미치는 간접효과가 더 크게 나타났다. 이는 연구개발비 규모나 GDP 대비 비중을 꾸준히 유지시킬 필요성과 고급인력양성의 중요성을 시사한다. 또한, 과학기술논문수는 GDP에 가장 큰 효과를 가지는 것으로 나타나, 연구개발로 창출된 새로운 지식 및 기술이 공유 확산됨으로써 새로운 성과와 가치로 이어진다는 것을 시사한다고 할 수 있다.

• 자원환경지질
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• 제52권2호
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• pp.199-212
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• 2019

머신러닝 기법을 활용한 분석에서 훈련 데이터의 샘플링 전략은 예측 정확도 뿐 만 아니라 일반화 능력에도 많은 영향을 미친다. 특히, 산사태 취약성 분석의 경우, 산사태 발생부에 대한 정보에 비해 산사태 미발생부에 대한 정보가 과도하게 많은 데이터 불균형 현상이 발생하며, 이에 따라 분석 모델의 훈련 데이터 설계 시 데이터 샘플링 과정이 필수적이다. 그러나 기존의 연구들은 대부분 산사태 미발생부 선택 시 발생부 데이터와 1:1의 비율을 갖도록 무작위로 선택하는 방법을 적용하였을 뿐, 특정한 선택 기준에 따라 분석을 수행하지 않았다. 따라서 본 연구에서는 훈련 데이터의 샘플링 전략이 모델의 예측 성능에 미치는 결과를 확인하기 위하여 산사태 발생부와 미발생부의 샘플링 전략기준에 따라 서로 다른 6개의 시나리오를 만들어 Random Forest 모델의 훈련에 사용하였다. 또한 Random Forest의 결과 중 하나인 변수 중요도를 각 산사태 유발인자들에 가중치로 곱하여 줌으로써 산사태 취약지수 값을 산정하였으며, 취약지수 값을 이용해 산사태 취약성도를 제작하고 각 결과 지도의 정확도를 비교 분석하였다. 분석 결과, 훈련데이터의 샘플링 방법에 상관없이 두 지역의 산사태 취약성 분석 결과는 모두 70~80%의 정확도를 보였다. 이를 통해 Random Forest 기법의 산사태 취약성 분석기법으로서의 적용 가능성을 확인하였으며, Random Forest 모델이 제공하는 입력변수의 중요도를 산사태 유발인자 가중치로 활용할 수 있음을 확인하였다. 또한 훈련 시나리오 간의 정확도를 비교한 결과, 특정한 기준에 의해 훈련 데이터를 설계하는 것이 기존의 랜덤 선택 방법보다 높은 예측 정확도를 기대할 수 있음을 확인하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1254-1263
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• 1993

Representing knowledge uncertainty , aggregating evidence confidences , and propagation uncertainties are three key elements that effect the ability of a rule-based expert system to represent domains with uncertainty . Fuzzy set theory provide a good mathematical tool for representing the vagueness associated with a variable when , as the condition of a rule , it only partially corresponds to the input data. However, the aggregation of ANDed and Ored confidences is not as simple as the intersection and union operators defined for fuzzy set membership. There is, in fact, a certain degree of compensation that occurs when an expert aggregates confidences associated with compound evidence . Further, expert often consider individual evidences to be varying importance , or weight , in their support for a conclusion. This paper presents a flexible approach for evaluating evidence and conclusion confidences. Evidences may be represented as fuzzy or nonfuzzy variables with as associat d degree of certainty . different weight can also be associated degree of certainty. Different weights can also be assigned to the individual condition in determining the confidence of compound evidence . Conclusion confidence is calculated using a modified approach combining the evidence confidence and a rule strength. The techniques developed offer a flexible framework for representing knowledge and propagating uncertainties. This framework has the potention to reflect human aggregation of uncertain information more accurately than simple minimum and maximum operator do.

• 한국항해항만학회지
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• 제34권9호
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• pp.719-726
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• 2010

As the competition among the container terminals in Korea has become increasingly fierce, every terminal is striving to increase its investments constantly and lower its operational costs in order to maintain the competitive edge and provide satisfactory services to terminal users. The unreasoning behavior, however, has induced that substantial waste and inefficiency exists in container terminal production. Therefore, it is of great importance for the terminal to know whether it has fully used its existing infrastructures and that output has been maximized given the input. From this perspective, data envelopment analysis (DEA) provides a more appropriate benchmark. This study applies three models of DEA to acquire a variety of analytical results about the operational efficiency to the Korean container terminals. According to efficiency value analysis, this study first finds the reason of inefficiency. It is followed by identification of the potential areas of improvement for inefficient terminals by applying slack variable method and giving the projection results. Finally, return to scale approach is used to assess whether each terminal is in a state of increasing, decreasing, or constant return to scale. The results of this study can provide terminal managers with insight into resource allocation and optimization of the operating performance.

• Journal of Korea Trade
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• 제25권8호
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• pp.25-44
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• 2021

Purpose - This research aims to provide empirical evidence that highlights the importance of imported intermediate goods in long-term economic growth. To this end, this paper develops an index that measures the productivity gains associated with a country's intermediate goods imports using highly disaggregated trade data. Design/methodology - The basic hypothesis is that countries sourcing higher-productivity (or higher-quality) inputs from developed economies derive a larger benefit from foreign R&D. To explore this hypothesis, standard cross-country growth regressions are performed using the highly disaggregated data from the United Nations (UN) Commodity Trade Statistics Database (COMTRADE). To address the endogeneity issue, I apply an instrumental variable (IV) approach. Findings - The results of this study demonstrate that the index predicts subsequent economic growth in middle- and low-income countries. This finding is consistent with previous studies that have argued that developing countries can achieve substantial productivity gains by importing intermediate inputs from developed countries. By contrast, there is no evidence of a significant association between the index and economic growth in high-income countries. Originality/value - This paper contributes to our understanding of the causal relationship between international trade and economic growth. From an economic policy perspective, the results suggest that developing countries with limited technology endowment can boost growth from input-tariff liberalization.