• Journal of Korean Society for Quality Management
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• v.33 no.4
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• pp.75-87
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• 2005

Generally speaking, weapon system is defined as a combination of primary system and support system which are evaluated by capability and operational availability respectively. Recently comparison of total life cycle cost shows that logistic support system is proved to be more important than primary system. However, until now systematic approach to support system development has not been applied in the area of developing support system. We need to construct a universal metric for effectiveness of logistic support system and to cut out whatever activities or support elements which do not contribute to the metric. This paper describes a new approach based on system engineering approach to logistic support system and also classifies five factors of failure, stock-out frequency, administrative delay time, active repair time and logistic delay time that have influence on operational availability of logistic support system.

• Journal of the Korean Data and Information Science Society
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• v.25 no.4
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• pp.941-949
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• 2014

Unit level logistic regression model with mixed effects has been used for estimating small area proportions, which treats the spatial effects as random effects and assumes linearity between the logistic link and the covariates. However, when the functional form of the relationship between the logistic link and the covariates is not linear, it may lead to biased estimators of the small area proportions. In this paper, we relax the linearity assumption and propose two types of kernel-based logistic regression models for estimating small area proportions. We also demonstrate the efficiency of our propose models using simulated data and real data.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.2
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• pp.1-10
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• 2013

In this paper, make a study decision problem called an optimal release policies after testing a software system in development phase and transfer it to the user. In the course of correcting or modifying the software, finite failure non-homogeneous Poisson process model, presented and was proposed release policies of the life distribution, half-logistic and log-logistic distributions model which used to an area of reliability because of various shape and scale parameter. In this paper, discuss optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement. In a numerical example, the parameter estimation using maximum likelihood estimation of failure time data make out, and software optimal release time was estimated.

• Journal of the Korean Data and Information Science Society
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• v.15 no.2
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• pp.367-378
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• 2004

Recently logistic regression is popular in a variety of fields so that a number of statistical packages are developed for analyzing the logistic regression. This paper briefly considers the several types of logistic regression models used depending on different types of data. In addition, when four statistical packages (MINTAB, SAS, SPSS and STATA) are used to apply logistic regression models to the real fields respectively, their scope and characteristics are investigated.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.113-119
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• 2015

This study is to examine the workers' awareness of the safety in logistic centers. For that purpose, the exploratory factor analysis of workers' safety awareness in logistic centers was performed at first, and the 6 variables extracted from the factor analysis were then used to investigate the difference in intergroup awareness of the safety environment in the logistic centers. We administered a survey to 147 workers attending the logistic centers and collected data from them. The results of the study showed that the intergroup awareness of the safety environment turned out to be statistically different from each other in terms of working environment, safe behavior, work risk, safety knowledge and effort, risk justification and compromising attitudes. Experiences in industrial accidents influenced awareness of working environment, work risk and risk justification. The group who experienced accidents is more likely to feel risky and unsatisfied with working place, and their awareness toward risk justification was high as well. It was also observed that there exists awareness difference between manager group and worker group. The group who manages the working place showed more positive awareness of working environment, safe behavior, work risk, safety knowledge and effort, risk justification and compromising attitudes than the worker group. On the contrary, the worker group showed high recognition in risk of working place, and felt that they are willing to compromise on safety for increasing production. The scale of the logistic center produced negative influence on awareness of safety. The group in small logistic center showed the highest awareness in safety, whereas the group in large logistic center with more than 100 workers showed the highest awareness in risk. They are more likely to deviate from correct and safe work procedures due to over-familiarity with the job, as well. The findings suggest that there is a need for the safety management and education to change the workers' understanding and attitudes towards safety.

• The Korean Journal of Applied Statistics
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• v.14 no.1
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• pp.71-80
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• 2001

Logistic regression model is one of the most popular linear models for a binary response variable and used for the estimation of probability function. In many practical situations, the probability function can be expressed by a bell shaped curve and such a function can be estimated by a second order logistic regression model. However, when the probability curve is asymmetric, the estimation results using a second order logistic regression model may not be precise because a second order logistic regression model is a symmetric function. In addition, even if a second order logistic regression model is used, the interpretation for the effect of second order term may not be easy. In this paper, in order to alleviate such problems, an estimation method for asymmetric probabiity curve based on a first order logistic regression model and iterative bi-section method is proposed and its performance is compared with that of a second order logistic regression model by a simulation study.

• The Journal of Society for e-Business Studies
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• v.14 no.4
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• pp.315-332
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• 2009

In logistic environments, a process, in that it manages the flow of materials among partners, involves more than one organization. In this regard, a logistic process, as a combined process consisting of multiple sub processes, needs to be managed with controling interaction among partners. In achieving systematic management of a logistic process, traditional Business Process Management (BPM) cannot be used for the entire flow, since it lacks the ability to manage interactions among partners. Particularly in logistic environments where RFID technologies are used, how to deal with the connection between RFID event and logistic flow has not been properly addressed. To overcome this limitation, this paper proposes a new method of managing multi-organizational logistic processes based on RFID events. We define inter-workflow pattern, and suggest ECA(Event-Condition-Action) rules for auto triggering of logistic processes. To adjust the rules to RFID events, we invent RFID-based ECA rules using complex event. A prototype system has been developed for the purpose of demonstrating the effectiveness of our approach.

• Journal of Biosystems Engineering
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• v.29 no.5 s.106
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• pp.441-450
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• 2004

This study was performed to estimate mid and long term demands of a tractor, a rice transplanter, a combine and a grain dryer by using logistic curve function and Markov chain model. Field survey was done to decide some parameters far logistic curve function and Markov chain model. Ceiling values of tractor and combine fer logistic curve function analysis were 209,280 and 85,607 respectively. Based on logistic curve function analysis, total number of tractors increased slightly during the period analysed. New demand for combine was found to be zero. Markov chain analysis was carried out with 2 scenarios. With the scenario 1(rice price $10\%$ down and current supporting policy by government), new demand for tractor was decreased gradually up to 700 unit in the year 2012. For combine, new demand was zero. Regardless of scenarios, the replacement demand was increased slightly after 2003. After then, the replacement demand is decreased after the certain time. Two analysis of logistic owe function and Markov chain model showed the similar trend in increase and decrease for total number of tractors and combines. However, the difference in numbers of tractors and combines between the results from 2 analysis got bigger as the time passed.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.2001-2005
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• 2006

우리나라는 매년 집중호우로 인한 산사태로 인해 인적, 물질적 피해를 일으킨다. 반복적인 산사태의 피해를 방지 하기위해서는 산사태 예측 시스템이 필요하다. 본 연구에서는 안성시를 대상으로 GIS와 RS 자료를 활용하여 산사태 위험지를 분석하고자 Logistic 회귀분석 방법과 AHP 기법을 이용하였다. Logistic 회귀분석과 AHP 기법에는 6개의 인자(경사, 경사향, 고도, 토양배수, 토심, 토지이용)를 사용하여, 7등급으로 산사태 위험도를 분류하였다. Logistic 회귀분석 방법과 AHP 기법을 이용한 산사태 위험지도를 표본 자료와 비교하면 산사태가 발생한 표본에서 산사태 위험성이 높은(1-2등급)지역이 Logistic 회귀분석에서는 46.1% AHP 기법은 48.7%로 분류되어 AHP 기법이 분류도가 높다고 분석 되었다. 하지만 Logistic 회귀분석과 AHP 기법은 서로 분석 과정의 차이를 가지고 있기 때문에 Logistic 회귀분석과 AHP기법을 적용한 결과에 동일 가중치를 부여한 후 7개 등급으로 재분류(reclass)하여 산사태 위험지역을 추출 할 수 있는 방법론을 제시하였다. 그 결과 산사태가 발생한 표본에서 1-2등급지역이 58.9%로 분석되어 분류정확도를 높일 수 있었다.

• Journal of Korea Port Economic Association
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• v.24 no.1
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• pp.85-102
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• 2008

The purpose of this study is to analyze the effects of Logistic Information System on performance by efficiency of internal operation and organizational innovation. The results of this study as follows : The characteristic variable evaluation model that extended from the performance(user's value, perceived usefulness) of Logistic Information System were verified meaningfully. In this study, the efficiency of internal operation and organizational innovation were very important factor, to analyze the effects of Logistic Information System on performance. This study expect that Logistic Information System will achieve their Logistic Information System competitiveness through continuous quality measurement and improvement to increase the performance.