• International Journal of Reliability and Applications
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• 제2권3호
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• pp.199-207
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• 2001

The failure rate functions between successive failures are of concatenated form. We allow the parameters of failure rate function change after a certain failure and its fixing. We confine out attention to a model wherein the interfailure times are described by its failure rate function. We suggest an adaptive failure rate function with a change-point under the assumption that interfailure times are record value statistics from a Weibull distribution. The proposed model will be applied through a practical example of software failure data.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권3호
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• pp.403-412
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• 2018

Medium-scale tests were conducted to measure and observe the strength and failure behavior of freshwater ice rubble. A custom box measuring $3.05m{\times}0.94m{\times}0.94m$, with Plexiglas walls was built so that failure mechanisms could be observed. Ice rubble beams of nominal thickness 50 cm were produced by placing randomly sized ice pieces into the box filled with water at its freezing temperature. After the specified consolidation time, ranging between 0.2 and 70.5 h, the ice rubble beam was deformed by pushing a platen vertically downwards though the center of the beam until failure. For consolidation times less than 4 h, the ice beam failed progressively and tended to fail by shearing on macroscopic scale. At times greater than 4 h the beam failed by bending. The change in failure behaviour has been attributed to the degree of bonding between ice blocks.

• 산업공학
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• 제15권1호
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• pp.89-98
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• 2002

This paper considers the optimum replacement times of a steam generator in nuclear power plant with failure data. It is assumed that the failure pattern of units is given as a Weibull distribution and repair and periodic preventive maintenance are performed periodically. The maximum likelihood method is used to estimated the Weibull parameters of failure distribution from failure data. Relpacement, output-decresing and maintenance costs are considered to determine the optimal replacement times by simulation. Numerical examples are included with actual failure data and cost estimators.

• 품질경영학회지
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• 제31권3호
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• pp.185-192
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• 2003

In this paper, the properties on the optimal replacement policies for the general failure model are developed. In the general failure model, two types of system failures may occur : one is Type I failure (minor failure) which can be removed by a minimal repair and the other, Type II failure (catastrophic failure) which can be removed only by complete repair. It is assumed that, when the unit fails, Type I failure occurs with probability 1-p and Type II failure occurs with probability p, $0\leqp\leq1$. Under the model, the system is minimally repaired for each Type I failure, and it is repaired completely at the time of the Type II failure or at its age T, whichever occurs first. We further assume that the repair times are non-negligible. It is assumed that the minimal repair times in a renewal cycle consist of a strictly increasing geometric process. Under this model, we study the properties on the optimal replacement policy minimizing the long-run average cost per unit time.

• 유공압시스템학회논문집
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• 제3권3호
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• pp.8-13
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• 2006

It is very important for the manufacturers to predict the life of hydraulic system components according to the results of life tests. Since it takes too much time to test the hydraulic system components until failure, the no-failure test method is applied for the life test of them. If the shape parameter of Weibull distribution, the number of samples, the confidence level, and the assurance life are given, the no-failure test times of hydraulic system components can be calculated by given equation. Here, the procedures to obtain the no-failure test times of the hydraulic system components such as hydraulic motors and pumps, hydraulic cylinders, hydraulic valves, hydraulic accumulators, hydraulic hoses, and hydraulic filters are described briefly.

• 한국심리학회지 : 문화 및 사회문제
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• 제14권1호
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• pp.101-123
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• 2008

본 연구는 남녀 대학생을 대상으로, 어머니와 연합된 성공/실패에 대한 표상을 알아보기 위해 시도되었다. 이를 위해 연구 1에서는 어머니/바구니와 성공/실패를 이중점화자극으로 100ms 동안 제시하고 난 뒤, 150ms 후(SOA 250ms)에 수용/거부와 관련된 목표자극(probe)을 제시하고 어의판단에 걸리는 시간을 측정하였다. 그 결과, 어머니조건의 반응이 통제조건보다 빨랐으며, 수용에 대한 반응이 거부 반응보다 빨랐고, 여자집단의 반응이 남자보다 빨랐다. 연구 2에서는 남녀별로 애착 고집단과 저집단을 나누어, 어머니와 성공/실패를 이중점화시킨 뒤 수용/거부에 대한 어의판단 시간을 측정하였다. 그 결과, 성공/실패와 수용/거부 간에 상호작용이 나타나, 성공-수용에 대한 반응은 가장 빨랐고, 실패-수용, 실패-거부, 성공-거부의 순으로 반응이 느려졌다. 한편 남자집단에서는 애착고저 집단 간에 유의미한 차이가 없고 상호작용도 나타나지 않았지만, 여자집단에서는 3원 상호작용이 나타났다. 즉 여자 애착 고집단에서는 성공-수용, 성공-거부에 대한 반응차이가 크지 않았고, 실패-거부에 대한 반응이 매우 느렸으나, 여자 애착 저집단에서는 성공-수용은 매우 빠른데 비해 성공-거부는 매우 느렸다. 이러한 결과는 자기 긍정성 및 성별, 애착유형에 따라 다른 성공/실패 도식과 관련하여 논의되었다.

• 지식경영연구
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• 제12권4호
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• pp.121-132
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• 2011

Failure, the research object, means situations when goals and their results are different, which has developed presenting various aspects from ancient times and modern times. Failure is a complex concept which essentially requires judgement, and also a relative concept which can be changed depending on how you set up time base and standard. There are four stages for failure study to have been developed from studying failure through historical facts to the approach of organizational theory and it has been studied by looking at the failure of an organization according to different categories such as a developmental stage, a type of business, a period and a course. Compared with success science, failure study has not been studied sufficiently and also the level of its analysis is low. Thus, since lessons of failure tend to repeat themselves instead of being didactically accumulated, there need more studies on this. This thesis identified the main cause of the failure through various studies regarding failure which have been conducted at home and abroad. What the main cause of the failure that more than three studies mentioned have in common was that it occurred because organizations concentrated on the inside without communicating with external environment. The key point of failure study is to analyze failure, utilize it as assets, and create a frame of failure management. This thesis focused on delivering fragmentary knowledge on failure study, but case studies regarding this subject should be done in the future.

• Communications for Statistical Applications and Methods
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• 제21권1호
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• pp.93-103
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• 2014

This paper deals with the problem of predicting censored data in a half triangle distribution with an unknown parameter based on progressively Type-II censored samples. We derive maximum likelihood predictors and some approximate maximum likelihood predictors of censored failure times in a progressively Type-II censoring scheme. In addition, we construct the shortest-length predictive intervals for censored failure times. Finally, Monte Carlo simulations are used to assess the validity of the proposed methods.

• Journal of the Korean Data and Information Science Society
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• 제20권5호
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• pp.933-939
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• 2009

The bivariate data in clinical research fields often has two types of failure times, which are mark variable for the first failure time and the final failure time. This paper showed how to generate bootstrap data to get Bayesian estimation for the joint distribution of bivariate survival times. The observed data was generated by Frank's family and the fake date is simulated with the Gamma prior of survival time. The bootstrap data was obtained by combining the mimic data with the observed data and the simulated fake data from the observed data.

• 지식경영연구
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• 제15권3호
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• pp.1-12
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• 2014

It is tried to draw the failure traits of leadership by extracting leadership parts from previous failure studies and including some parts which mention failure leadership among leadership-related books. All of 5 patterns are drawn through total 13 types of study data. From 'insensitive to change' and authoritarianism which is mentioned 8 times in such 13 studies, to 'interpersonal problem', which is mentioned five times, traits which are mentioned at least five times are selected. There are drawn 5 traits including ${\Delta}$ authoritarianism ${\Delta}insensitive$ to change ${\Delta}lack$ of executive ability ${\Delta}populism$ and ${\Delta}interpersonal$ problem. As being examined in these 5 types of failure traits, the failure of leadership is ultimately happened because of communication heading for the inside without any communication(exchange) to the outside. That is, it is understood that authoritarian leaders don't perceive change correctly but make a wrong communication (populism) or break down communication. Additionally, the executive ability is to perform actually one's idea and to be achieved through incessant communication with members. Compared with other various studies to draw failure factors, these leadership traits have something in common. In the previous researches conducted the study of general failure factors, ${\Delta}adherence$ to preexisting business and resistance to change ${\Delta}unfeasible$ expansion strategy ${\Delta}blind$ faith in successful technology and innovation and ${\Delta}insufficiency$ to grasp competitor(consumer) are pointed out as the failure factors. It is deemed that these are happened because organizational management is headed for the inside without any communication (exchange) to the external environments. Matters unfolded through this paper until now are an attempt to apply the failure knowledge to a leadership part which is an individual field in business administration. It is considered that this study will be complemented through additional case study or quantitative analysis in the future.