• International Journal of Reliability and Applications
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• v.2 no.3
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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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• v.10 no.3
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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.

• IE interfaces
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• v.15 no.1
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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.

• Journal of Korean Society for Quality Management
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• v.31 no.3
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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.

• Transactions of The Korea Fluid Power Systems Society
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• v.3 no.3
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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.

• Korean Journal of Culture and Social Issue
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• v.14 no.1
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• pp.101-123
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• 2008

We investigated the implicit representations of success/failure associated with mother in male and female college students. In study 1, participants were presented 'mother' or 'basket' as a context prime and 'success' or 'failure' related words as second primes for 100ms, and were asked to make lexical decisions about 'accept' or 'reject' related words and non-words after 150 ms (SOA 250ms). Results revealed that lexical decision times on the mother condition were more rapid than the ones on the basket condition, and lexical decision times on the acceptance condition were more rapid than the ones on the rejection condition, and female participants showed shorter times than male students did. In study 2, we divided participants into four groups by gender and attachment style, Results showed that the interaction between success/failure and acceptance/rejection was statistically significant, that is, quickest lexical decision times on the success-acceptance condition, and slowed times on failure-acceptance, failure-rejection, and success-rejection condition in order. On the other hand, no significant differences between high and low attachment group were found in males, but significant three-way interactions were found in females. In highly attached females, lexical decision times in success-acceptance condition were not differed from ones in success-rejection condition, and slowed times in failure-rejection condition. Low attached females showed very rapid times in success-acceptance condition, but very slow times in success-rejection condition. The results were discussed in terms of self-positivity and success/failure scheme depending on gender and attachment styles.

• Knowledge Management Research
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• v.12 no.4
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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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• v.21 no.1
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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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• v.20 no.5
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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.

• Knowledge Management Research
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• v.15 no.3
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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.