• 한국포장학회지
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• 제7권1호
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• pp.16-20
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• 2001

In order to optimize designing process of corrugated fiberboard boxes for agricultural products, first of all, compression strength of each liner were experimentally evaluated on the various conditions of relative humidity and analyzed by liner regression analysis. At the 66 percents of relative humidity, IK(imported kraft liner) liner board lost little of its compression strength compared to others. At the relative humidity 93 percents, KA liner board lost its compression strength only 40 percents while SK liner board lost up to 56 percents. From the result of prediction modeling of ring crush strength in various humidity conditions, R square values were ranged from 0.59 to 0.97. At 56 percents of RH or below, R square values were relatively low, but at 66 percents of RH or higher, the values were 0.85 or higher. The significance values were lower than 0.001 at every RH condition. Level of significance of experimented values was about 80 percents of predicted values and R square values were between 0.89 to 0.95.

• 한국항만경제학회지
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• 제33권1호
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• pp.89-110
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• 2017

국제 해운시장에서는 규칙적이고 반복적으로 이루어지는 정기선 서비스의 특수성을 인정하여 정기선사 간의 과당 경쟁을 방지하고 항로의 질서 유지와 안정화를 위해 국제 카르텔인 해운동맹의 결성을 인정하였다. 하지만 선박대형화와 복합운송의 발달 그리고 비동맹선사의 세력확대로 인하여 해운동맹은 와해되기 시작하였으며 결국 폐지되기에 이르렀다. 정기선 시장에서 중요한 역할을 담당했던 해운동맹이 폐지되면서 정기선 시장의 경쟁구도는 변화를 겪기 시작하였다. 따라서 해운동맹의 폐지가 정기선 시장에 미친 영향에 대한 연구가 필요하게 되었으며 해운동맹의 폐지로 인하여 영향을 받은 요소를 선정하여 상관분석과 다중 회귀분석을 통하여 영향을 분석하였다. 분석 결과, 해운동맹의 폐지로 인하여 각 선사들은 선복량 증가로 운임 경쟁이 심화되었고 결국 비용구조가 유리한 선사는 수익을 창출하고 그렇지 못한 선사는 적자를 기록하게 되었다.

• 한국항해항만학회지
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• 제27권2호
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• pp.163-170
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• 2003

본 연구는 한중정기항로에서 국적선사 활성화 방안에 관한 실증연구이다. 본 연구를 위하여 한중항로의 국적정기선사, 중국적 정기선사, 3국적 정기선사 등의 종사자에 실문지 500매를 배포하여 290매 회수하였으며, 한중정기항로 국적선사 활성화 요인과 물동량 증대효과의 관련성을 검증하기 위하여 먼저, 설문문항의 신뢰성(Reliability)은 크론바하 알파(Cronbach's Alpha)에 의한 내적 일관성 검사법을 통하여 검정하였고, 독립변수의 구성타당성(Construct Validity)을 검정하기 위해서 변수들이 선형결합이라는 가정 하에 요인을 추출하는 주성분 법(Principal Components)을 이용한 요인분석(Factor Analysis)을 실시하였다. 그리고 연구가설을 검증하기 위하여 다변량 회귀분석(Multiple Regression Analysis)을 실시하였다.

• Journal of Korea Trade
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• 제27권1호
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• pp.79-100
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• 2023

Purpose - The purpose of this study is to analyze the market power of the Korea Container Shipping Market (Intra Asia, Korea-Europe, and Korea-U.S.) to verify the existence of collusion empirically, and to answer whether the joint actions of liner market participants in Korea have formed market dominance for each route. Precisely, it will be verified through the Lerner index as to whether the regional market of Asia is a monopoly, oligopoly, or perfect competition. Design/methodology - This study used a Lerner index adjusted with elasticity presented in the New Imperial Organization (NEIO) studies. NEIO refers to a series of empirical studies that estimate parameters to judge market power from industrial data. This study uses B-L empirical models by Bresnahan (1982) and Lau (1982). In addition, NEIO research data statistically contain self-regression and stability problems as price and time series data. A dynamic model following Steen and Salvanes' Error Correction Model was used to solve this problem. Findings - The empirical results are as follows. First, λ, representing market power, is nearly zero in all three markets. Second, the Korean shipping market shows low demand elasticity on average. Nevertheless, the markup is low, a characteristic that is difficult to see in other industries. Third, the Korean shipping market generally remains close to perfect competition from 2014 to 2022, but extreme market power appears in a specific period, such as COVID-19. Fourth, there was no market power in the Intra Asia market from 2008 to 2014. Originality/value - Doubts about perfect competition in the liner market continued, but there were few empirical cases. This paper confirmed that the Korea liner market is a perfect competition market. This paper is the first to implement dynamics using ECM and recursive regression to demonstrate market power in the Korean liner market by dividing the shipping market into Deep Sea and Intra Asia separately. It is also the first to prove the most controversial problems in the current shipping industry numerically and academically.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.339-343
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• 2005

Boolean networks(BN) construction is one of the commonly used methods for building gene networks from time series microarray data. However, BN has two major drawbacks. First, it requires heavy computing times. Second, the binary transformation of the microarray data may cause a loss of information. This paper propose two methods using liner regression to construct gene regulatory networks. The first proposed method uses regression based BN variable selection method, which reduces the computing time significantly in the BN construction. The second method is the regression based network method that can flexibly incorporate the interaction of the genes using continuous gene expression data. We construct the network structure from the simulated data to compare the computing times between Boolean networks and the proposed method. The regression based network method is evaluated using a microarray data of cell cycle in Caulobacter crescentus.

• 한국항만경제학회지
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• 제31권4호
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• pp.189-207
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• 2015

본 연구의 목적은 네트워크 이론 관점에서 정기선 운항에 따른 해운네트워크 분석을 통한 세계 주요 항만의 중심성을 분석해 보고 항만경쟁력으로 대변되는 항만물동량에 미치는 영향에 대해 알아봄으로써 선사 중심의 항만경쟁력 평가 및 항만당국 및 항만운영자의 컨테이너항만 경쟁력 향상방안과 개발정책에 필요한 근거를 마련하는데 있다. 항만의 네트워크 중심성을 파악하기 위해 이용된 데이터는 Containerization Yearbook과 online의 2007년부터 2011년까지 6년간의 정기선사 서비스 및 항만 데이터를 활용하였으며 분석방법으로는 그래프 이론의 한 부문인 사회 네트워크 분석(SNA: Social Network Analysis)을 이용하였다. 또한 이를 통해 도출된 주요 항만의 중심성과 항만경쟁력에 영향을 미치는 요인을 선행연구를 통해 도출하여 항만물동량과의 패널 회귀분석을 실시하였다. 연구결과, 세계 주요항만의 중심성을 분석하여 시간에 흐름에 따른 항만 네트워크 내 역할에 대해 파악되었고, 고정효과모형(Fixed effect model)으로 선택된 패널회귀분석을 통해 거시경제변수인 GDP, 선석의 변화율 및 항만 중심성 중 위세 중심성(Eigenvector Centrality)이 정(+)의 영향을 미치는 변수로 분석되었다.

• 한국콘텐츠학회논문지
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• 제21권7호
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• pp.609-618
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• 2021

본 연구의 목적은 자녀를 두고 있는 어머니의 분노와 우울이 유아문제행동에 미치는 영향을 확인하는데 있다. 자료수집은 2019년 5월 1일부터 7월 1일까지이며, 대전, 부산, 울산에 소재한 3곳의 유아교육기관에 영유아 자녀를 위탁한 어머니 244명이었다. 수집된 자료는 SPSS/WIN 24.0을 사용하여 기술통계, t-test, ANOVA, Pearson correlation coefficient, multiple liner regression analysis를 이용하였다. 본 연구 결과 유아문제행동은 어머니의 분노(r=.261, p<.001), 우울(r=.435, p<.001)과 통계적으로 유의한 정적 상관관계가 있는 것으로 나타났다. 다중회귀분석결과 유아문제행동에 유의하게 영향을 미치는 요인은 어머니의 우울(𝛽=16.57, p<.001)로 총 설명력은 19.2%이었다. 따라서 어머니의 정서적 지지와 함께 우울영향 요인 감소를 지원하는 부모교육프로그램 개발 필요성에 대한 시사점을 제공하였다.

• 한국항해항만학회지
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• 제30권7호
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• pp.579-583
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• 2006

The purpose of this paper is to study a relationship between alliance success factors and performances of strategic alliance. In order to achieve the purpose of this research, factor analysis, reliability and validity and regression method are used. In conclusion, alliance success factors can be divided as mutual complementarity and information sharing factor, sharing and mutual agreement of vision and goal factor, performance management factor and culture and organization factor. According to regression results, all of four factors affects significantly dependent variables. Among them, mutual complementarity and information sharing mostly affects each dependent variable.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.566-573
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• 1999

This paper is the result of sensitivity analysis of derailment with respect to the selected suspension elements for the rail vehicle. Derailment phenominon has been explained by the derailment quotient. Thus, the sensitivity of derailment is suggested by a response surface model(RSM) which is a functional relationship between derailment quotient and characteristics of suspension elements. To summarize generation of RSM, we can introduce the procedure of sensitivity analysis as follows. First, to form a RSM, a experiment is performed by a dynamic analysis code, VAMPIRE according to a kind of the design of experiments(DOE). Second, RSM is constructed to a 1$\^$st/ order polynomial and then main effect fators are screened through the stepwise regression. Finally, we can see the sensitivity level through the RSM which only consists of the main effect factors and is expressed by the liner, interaction and quadratic effect terms.

• 한국직업건강간호학회지
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• 제25권3호
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• pp.199-207
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• 2016

Purpose: The purpose of this study was to identify the obesity stress, weight bias and health care on Body Mass Index (BMI) in soldiers of non-combat area and to provide data for improving the quality of their life. Methods: This research involved 165 soldiers working in non-combat area. Data collection was conducted from November 1 to 20, 2015. Statistical analysis of the collected data were t-test and ANOVA, $Scheff{\acute{e}}$ method post hoc analysis, Pearson's correlation coefficients, and multiple liner regression using IBM SPSS 22.0. Results: The mean score of obesity stress was moderate ($19.05{\pm}5.28$). The mean score of weight bias was 69.03 and health care was 2.41 points. There are a positive correlation between obesity stress and BMI (r=.19, p<.05). Weight bias (r=-.19, p<.01) and health care (r=-.26, p<.01) among the subjects had negative correlations with BMI. In a multiple liner regression, obesity stress (${\beta}=.18$, p<.05), health care (${\beta}=-.18$, p<.05) were associated with BMI. Conclusion: Based on the findings that obesity stress and health care influence BMI, there is a need to control stress and to properly set proper guidelines on health care for soldiers.