• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.3
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• pp.191-198
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• 2014

Using results of groundwater flow system modeling for a hypothetical deep geological repository site, a distribution of groundwater flow rates at the disposal depth was analyzed and a method of applying this distribution to a safety assessment for a disposal of radioactive wastes was suggested. The distribution of groundwater flow rates was produced by hydraulic heads simulated from regional and local scale groundwater flow models for the hypothetical disposal site. The flow rates at the locations where deposition holes would be located were estimated. These rates were normalized by the maximum of the flow rates in order to probabilistically illustrate a possibility of canister failures at the deposition holes. From the normalized distribution, probabilistic expectations for mass discharges of radionuclides released from the canisters assumed to be failed were calculated and compared with those deterministically estimated under the assumption that the canisters at the same deposition holes were definitely failed. The suggested method can be contributed to constructing a methodology for safety assessment of a geological repository by reflecting natural conditions of a disposal site in more detail.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.425-435
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• 2017

Structural analysis is used not only for large enterprises, but also for small and medium sized ones, as a necessary procedure for strengthening the certification process for product delivery and shortening the time in the process from concept design to detailed design. Open-source solvers that can be used atlow cost differ from commercial solvers. If there is a problem with the input data, such as with the grid, errors or failures can occur in the calculation step. In this paper, we propose a pre- and post-processor that can be easily applied to the analysis of mechanical structural problems by using the existing structural analysis open source solver (Caculix, Code_Aster). In particular, we propose algorithms for analyzing different types of data using open source solvers in order to extract and generate accurate information,such as 3D models, grids and simulation conditions, and develop and apply information analysis. In addition, to improve the accuracy of open source solvers and to prevent errors, we created a grid that matches the solver characteristics and developed an automatic healing function for the grid model. Finally, to verify the accuracy of the system, the verification and utilization results are compared with the software used.

• Cartoon and Animation Studies
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• s.13
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• pp.163-179
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• 2008

It is no longer an issue that there is a big audience for Korean movies. More than 120 Korean movies are made each year. Many win prizes at film festivals around the world. But the number of animation movies made in Korea is decreasing even though the government tried to revitalize the animation industry in the mid-1990s. The problem is that all Korean animation movies were box-office failures, even though "Mary's Story" and "Oseam" were awarded prizes in world-famous animation festivals. Korean animation movies also face hurdles because of different cultural tastes of Korean audiences and problems with distribution. But there is a tremendous amount of potential and possibilities for Korean animation movies to be box-office blockbusters and artistic successes. There are ways to develop and revitalize the Korean animation industry and make it of the most important businesses and cultural influences in Korean society.

• Journal of Intelligence and Information Systems
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• v.11 no.3
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• pp.103-115
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• 2005

For today's enterprises to survive in the current rapidly changing business environments, it is imperative to make quick and successful decisions to various challenges. In making important business decisions, if enterprises utilize business rules and knowledge, properly and promptly, they may effectively reduce the chance of failures. However, in most of today's information systems, these rules and knowledge are not managed in centralized and systemic manner. They disperse over entire enterprises' information systems, and sometimes reside in the heads or memos of enterprises' employees. BRE (Business Rule Engines) is a solution that systematically and centrally manages these business knowledge and rules of an enterprise. With BREs, any business user is able to store, edit, retrieve and utilize business rules and knowledge in centralized repository, without IT development skills. And with BRE, enterprises could improve business intelligence and attain strategic advantages over other enterprises. However, since there is no clear criteria for BRE introductions, it is not easy to decide whether or not to introduce the expensive BRE solution to an enterprise. In this research we propose a decision model for BRE introduction. Using this model, business analysts considering BRE introduction, readily make decisions on BRE introduction.

• Journal of Forest and Environmental Science
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• v.23 no.1
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• pp.35-49
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• 2007

This study analyzed on the developmental process of forest policy direction in Korea and present status of forest desolation in North Korea of the pre and post division of the Korean peninsular with historical point of view and indicates future tasks to take. Forests in Korea were destroyed in the early of 1900s while Korean peninsular was under Japanese colonial rule. In 1945, Korea was divided into two parts, which developed its own forest policy under the different political system. South Korea was at Korean war in 1950 and accomplished the greening movement from 1970s to 1980s. After 1990s, the country has aimed to sustainable forest management. North Korea has focused on forestation until 1960. However, the result has been doubtful with North Korean economic depression, and these days North Korea faces forest desolation due to failures of forest management. Therefore, necessary is that recovery measures for forest desolation in North Korea, cooperation and interchange between North and South Korea and plans of forest management in case of unification.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.128-139
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• 2017

Railway is one of the public transportation systems along with shipping and aviation. With the recent introduction of high speed train, its proportion is increasing rapidly, which results in the higher risk of catastrophic failures. The wheel bearing to support the train is one of the important components requiring higher reliability and safety in this aspect. Recently, many studies have been made under the name of prognostics and health management (PHM), for the purpose of fault diagnosis and failure prognosis of the bearing under operation. Among them, the most important step is to extract a feature that represents the fault status properly and is useful for accurate remaining life prediction. However, the conventional features have shown some limitations that make them less useful since they fluctuate over time even after the signal de-noising or do not show a distinct pattern of degradation which lack the monotonic trend over the cycles. In this study, a new method for feature extraction is proposed based on the observation of relative frequency energy shifting over the cycles, which is then converted into the feature using the information entropy. In order to demonstrate the method, traditional and new features are generated and compared using the bearing data named FEMTO which was provided by the FEMTO-ST institute for IEEE 2012 PHM Data Challenge competition.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.3
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• pp.246-252
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• 2016

Since thermal power plant (TPP) equipment is operated under very high pressure and temperature, failures of the equipment give rise to severe losses of life and property. To prevent the losses, fault detection method is, therefore, absolutely necessary to identify abnormal operating conditions of the equipment in advance. In this paper, we present Mahalanobis distance (MD) based fault detection method for steam boiler tube in TPP. In the MD-based method, it is supposed that abnormal data samples are far away from normal samples. Using multivariate samples collected from normal target system, mean vector and covariance matrix are calculated and threshold value of MD is decided. In a test phase, after calculating the MDs between the mean vector and test samples, alarm signals occur if the MDs exceed the predefined threshold. To demonstrate the performance, a failure case due to boiler tube leakage in 200MW TPP is employed. The experimental results show that the presented method can perform early detection of boiler tube leakage successfully.

• Journal of Applied Reliability
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• v.15 no.2
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• pp.90-100
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• 2015

Reliability growth rate (or reliability growth curve slope) have the two cases of trend as a constant or changing one during the reliability growth testing. The changing case is very common situation. The reasons of reliability growth rate changing are that the failures to follow the NHPP (None-Homogeneous Poisson Process), and the solutions implemented during test to break out other problems or not to take out all of the root cause permanently. If the changing were big, the "Goodness of Fit (GOF)" of reliability growth curve to test data would be very low and then reduce the accuracy of assessing result with test data. In this research, we are using Duane model and AMSAA model for assessing test data and projecting the reliability level of complex and repairable system as like construction equipment and vehicle. In case of no changing in reliability growth rate, it is reasonable for reliability engineer to implement the original Duane model (1964) and Crow-AMSAA model (1975) for the assessment and projection activity. However, in case of reliability growth rate changing, it is necessary to find the method to increase the "GOF" of reliability growth curves to test data. To increase GOF of reliability growth curves, it is necessary to find the proper parameter calculation method of interesting reliability growth models that are applicable to the situation of reliability growth rate changing. Since the Duane and AMSAA models have a characteristic to get more strong influence from the initial test (or failure) data than the latest one, the both models have a limitation to contain the latest test data information that is more important and better to assess test data in view of accuracy, especially when the reliability growth rate changing. The main objective of this research is to find the parameter calculation method to reflect the latest test data in the case of reliability growth rate changing. According to my experience in vehicle and construction equipment developments over 18 years, over the 90% in the total development cases are with such changing during the developing test. The objective of this research was to develop the newly assessing method and the process for GOF level increasing in case of reliability growth rate changing that would contribute to achieve more accurate assessing and projecting result. We also developed the new evaluation method for GOF that are applicable to the both models as Duane and AMSAA, so it is possible to compare it between models and check the effectiveness of new parameter calculation methods in any interesting situation. These research results can reduce the decision error for development process and business control with the accurately assessing and projecting result.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.2
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• pp.79-88
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• 2017

In this paper, the wind tunnel test for the measurement of aerodynamic characteristics of transmission conductors with asymmetric sections is described. A single conductor model and bundled conductor models with ice accreted shapes are tested both in steady and turbulent flow, and the aerodynamic coefficients are acquired. Transmission conductor galloping is a kind of wind-induced vibration which is characterized by primarily vertical oscillation with a very low frequency and a high amplitude. It is well known that transmission conductor galloping is generally caused by moderately strong, steady winds when a transmission conductor has an asymmetric cross-section shaped by accreted ice. Galloping should be considered from the design stage of overhead lines because it can cause severe wear and fatigue damage to attachments as well as transmission conductors. It is reported that there have been normally 20 events of galloping per year in Korea, which may be followed by serious consequences in the electric power system. Therefore, this research is performed to measure aerodynamic characteristics of ice accreted transmission conductors to understand and control transmission conductor galloping so that it would help to prevent unexpected failures and reduce the maintenance costs caused by galloping.

• Child Health Nursing Research
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• v.7 no.4
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• pp.434-450
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• 2001

This study is designed to understand the meaning and nature of raising children with cerebral palsy. It researches the experience of mothers of schoolchildren with cerebral palsy by the research method of hermeneutic phenomenology. The study was conducted from November 10, 1999 to December 20, 2000. When children with cerebral palsy usually show symptoms in the early stage of cerebral palsy, mothers do not take children to a doctor for diagnosis. And, most of mothers have a difficult time to accept the reality; they usually respond to the initial diagnosis with shock, reproach, and deny. When mothers start recognizing the reality, they consider that their children have cerebral palsy due to the their mismanagement during pregnancy, delivery, nursing, and initial treatment. They shelter their children from view and feel guilty that they cannot afford to try folk remedies for their children. As time passes, mothers face conflicts between families in diverse ways. Families put the blame on genetic effects. Mothers-in-law give their daughters-in-law a hard time, husbands shift the responsibility of raising children onto their wives, and trouble arises between families-in-law and mothers native families. When children grow up, it is physically difficult for mothers to take care their children. In addition, they suffer from all the troubles in family due to childrens handicap. Mothers try the diverse methods of bringing up children. However, they start getting tired of raising children as they experience failures and financial difficulties. Mothers feel collapsed recalling the ways of raising children. They feel anxiety, miserable, lonely, and worrying when they think how children would attend school, make friends, and live in the future. In this stage, mothers do their best to raise their children with hope. They tend to compare their children with others without handicap and spend money and time in attempting all the treatments. When mothers and children join the society at school, they find that the society does not understand disabled people, teachers show inconsiderate attitude, friends avoid them, and children hardly follow classes. Such experiences make mothers feel angry and frustrated. However, when children adapt to school, mothers see the possibility that children could accomplish schoolwork. They appreciate teachers help and others consideration. Mothers place appropriate expectations on their children and help them to prepare for the future. I would make following suggestions based on the results. 1. As a primary basic course of rehabilitation nursing intervention, solution-centered nursing intervention system should be developed. The intervention needs to be based on the understanding of mothers, who raise children with cerebral palsy, through in-depth interview. 2. Advance researches on the development of individual nursing intervention should be conducted. Individual nursing intervention needs to prevent and release actual pain focusing on mothers raising children with cerebral palsy. 3. Integrated curriculum that help children with cerebral palsy lead a normal school life with ordinary children should be developed. 4. Basic research on using of facilities and effective application of service volunteer to help children with cerebral palsy in school needs to be conducted.