• Korean Journal of Materials Research
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• v.8 no.6
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• pp.565-570
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• 1998

SiCp/6061AI 복합재료의 파괴인성을 평가하기 위하여 정적파괴인성에 대해서는 복수시험편법을, 동적파괴인성시험에 대해서는 stop block법을 실시하였다. 주균열은 예비균열의 선단에서 시험편두께방향 전역에 걸쳐서 일시에 발생하는 것이 아니고, 균열발생의 초기단계에서 국부적으로 형성된 균열이 시험편두께방향으로의 균열의 확장을 완료한 후 주균열로 이행해 간다. 정적 및 동적시험에서 컴플라이언스변화율법에 의해 검출된 균열발생점은 균열확장의 완료점과 거의 일치하고 있기 때문에 본 재료의 파괴인성 결정에 유효하다. 본 재료에서 동적파괴인성치는 정적파괴인성치보다 크게 나타났다. 이것은 동적충격시 입자파괴에 의한 에너지의 흡수.분산효과와 균열진전경로의 큰 편향에 기인한다고 생각된다.

• Journal of Korea Water Resources Association
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• v.45 no.5
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• pp.481-493
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• 2012

The Uncertainty of drought events can be regarded as supernatural phenomena so that the uncertainty of water supply system will be also uncontrollable. Decision making for water supply system operation must be dealt with in consideration of hydrologic uncertainty conditions. When ultimate small quantity of precipitation or streamflow lasts, water supply system might be impacted as well as stream pollution, aqua- ecosystem degradation, reservoir dry-up and river aesthetic waste etc. In case of being incapable of supplying water owing to continuation of severe drought, it can make the damage very serious beyond our prediction. This study analyzes comprehensively sustained drought impacts on the Han River Basin Water Supply System. Drought scenarios consisted of several sustained times and return periods for 5 sub-watersheds are generated using a stochastic hydrologic time series model. The developed drought scenarios are applied to assess water supply performance at the Paldang Dam. The results show that multi-year drought events reflecting spatial hydrologic diversity need to be examined in order to recognize variation of the unexpected drought impacts.

• Journal of the Society of Disaster Information
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• v.14 no.2
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• pp.203-210
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• 2018

Purpose: The purpose of this study is to build a model for the meta - evaluation of the national infrastructure system and to improve the evaluation system of the national infrastructure system using the model. Method: For the study, the disaster-related laws and regulations, the evaluation report of the national infrastructure system published by the government, the guideline for the establishment of the national infrastructure protection plan, the meta-evaluation previous research data, To analyze the actual state of the evaluation. Results: Among the indices of evaluation of the current national infrastructure system, the supplementary requirements were derived from seven indicators such as appropriateness of education and training plan and implementation of disaster response, evaluation and communication with stakeholders, and evaluation committee training time. Conclusion: It is expected that the improvement plan derived from this study can be used to improve the evaluation index of the national infrastructure system.

• Journal of Energy Engineering
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• v.22 no.4
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• pp.406-412
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• 2013

The certification scheme for best company has been implementing in order to stimulate the investment of private consulting company to reduce GHG emission. This study was conducted to set up the certification scheme, to suggest process, criterion, institute, committee which are necessary for the evaluation of certificate. Evaluation process for the introduction of the certification scheme is divided into 7 successive phases, (1) Certificate application(Applicant ${\rightarrow}$ Certification Institute), (2) Evaluation request(Certification Institute ${\rightarrow}$ Evaluation Institute), (3) Accept and document review(Evaluation Institute), (4) Site and document evaluation(Evaluation Institute ${\rightarrow}$ Evaluation committee), (5) Sending evaluation result(Evaluation Institute ${\rightarrow}$ Certification Institute), (6) Certification confirmation (Certification Institute), (7) Issue of certificate(Certification Institute ${\rightarrow}$ Applicant).

• Korean Journal of Construction Engineering and Management
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• v.6 no.5 s.27
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• pp.128-138
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• 2005

The success of mergers and acquisitions(M&A) have been evaluated by either measuring ex ante expectations for the specified time period(Window) or assessing long term-based post operating performance (ex post operating performance). In this study, utilizing cumulative abnormal return(CAR) method, M&As which are observed in both domestic and U.S. construction industries were analyzed then research outcomes are compared. Analysis results indicate that stockholders of public construction companies did not realize significant economic gains from M&As. In other words, there was no synergistic gains from the construction M&As. Also, no significant performance difference was observed between related and unrelated diversifications.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.348-352
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• 1984

Sesamolin and sesamin in the five domestic varieties and seven of imported sesame seed were analyzed by High Performance Liquid Chromatography to evaluate quality of sesame oil. Their stability against roasting, changes of content during storage of sesame oil and differences in carry-through ratio by extracting method were also analyzed. The results indicated that the HPLC method was simple, rapid and reliable in the evaluation of sesame oil quality.

• Clinical and Experimental Pediatrics
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• v.51 no.2
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• pp.188-203
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• 2008

Purpose : Asthma is one of the most common chronic childhood disease. Education of asthmatic children and their families about asthma and its management may improve disease control, reduce symptoms, and improve school performance. The aim of the study was to evaluate the effects of an intensive asthma education program in asthmatic children and their families on outcome measure of asthma management behavior scale, knowledge about asthma, self efficacy scale and quality of life. Methods : Fifteen asthmatic children and their families were invited the intensive asthma education program which including allergen avoidance, management of asthma, correct use of the inhalation devices and control of exercise-induced asthma (study group). Fifteen asthmatic children and their families those who did not participate this program were served as control group. Participants were asked to complete a written questionnaire before and 3-month after the program. Results : After completing the intensive education program, significant improvement of the childrens asthma management behavior scale (27.1 vs. 32.2, P=0.011), belief and knowledge about asthma (14.2 vs. 17.9, P<0.001), self efficacy (47.9 vs. 49.7, P=0.091) and quality of life (79.6 vs. 88.6, P<0.001) was noted in the study group by measuring questionnaires. There are increasing tendencies in parental asthma management behavior scale and knowledge about asthma. Conclusion : This intensive asthma education program is effective in improving asthma control, self efficacy and quality of life of asthmatic children. This should serve as a national model for family-based programs for asthmatic children and their families.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.130-140
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• 2014

Recently, some of the previous studies reported that tolclofos-methyl is still exist in ginseng cultivated soil, even though it is has been banned for ginseng. Therefore, the current study was aimed to examine the levels of absorption and translocation of tolclofos-methyl from ginseng cultivated soil to ginseng root and leaf stem for the period of 1 year. For this study, ginseng plants were transplanted in pots and treated with $5.0mg\;kg^{-1}$ of tolclofos-methyl (50% WP). At the end of each interval periods (every three months) the samples (soil, roots and leaf stems) were collected and analyzed the absorption and translocation levels of tolclofos-methyl using gas chromatography and mass spectrometry (GC-MS). The limit of quantitation of tolclofos-methyl was found to be $0.02mg\;kg^{-1}$ and 70.0~120.0% recovery was obtained with coefficient of variation of less than 10% regardless of sample types. In this study, a considerable amount of translocation of tolclofos-methyl residues were found in soil (4.28 to $0.06mg\;kg^{-1}$), root (7.09 to $1.54mg\;kg^{-1}$) and leaf stem (0.79 to $0.69mg\;kg^{-1}$). The results show that the tolclofos-methyl was absorbted and translocated from ginseng cultivated soil to ginseng root and ginseng leaf stem and found to be decreased time-coursely. Secondly, we were also analyzed soil, root and leaf stems samples from Hongcheon, Cheorwon, Punggi and Geumsan by GC-MS/MS (172 pesticides), LC-MS/MS (74 pesticides). In this study, 43 different pesticides were detected ($0.01{\sim}7.56mg\;kg^{-1}$) in soil, root and leaf stem. Further, tolclofos-methyl was detected 4 times separately in root sample alone which is less ($0.01{\sim}0.05mg\;kg^{-1}$) than their maximum residual limit (MRL) in ginseng. Consequently, the results from both studies indicate the residues of tolclofos-methyl found in ginseng cultivated soil and ginseng ensuring their safety level. Moreover, long-term evaluations are needed in order to protect the soil as well as ginseng free from tolclofos-methyl residues.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.424-433
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• 2017

Antioxidants are used in the manufacturing of commercial food packages made of polyolefin plastic such as polyethylene and polypropylene for the purpose to delay the oxidation reaction of the polymer due to oxygen or traces of ozone in the atmosphere. Additives in plastics may be migrated from the packaging materials into foods, thereby presenting a potential health risk to the consumer. Therefore, it is necessary to determine migration level of antioxidants from food packaging materials to foodstuffs in order to take proactive management. In this study, we have developed a method for the analysis of 10 antioxidants, which are butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), Cyanox 2246, 425 and 1790, Irgafos 168, and Irganox 1010, 1330, 3114 and 1076, migrated from the food packaging materials into four food simulants for aqueous, acidic, alcoholic and fatty foods. The antioxidants were determined by reversed-phase high-performance liquid chromatograph-ultraviolet detector with 276 nm after solid-phase extraction with a hydrophilic-lipophilic balance (HLB) cartridge or dilution with isopropanol. The analytical method showed a good linearity of coefficient ($R^2{\geq}0.99$), limits of detection (0.11~0.41 mg/L), and limits of quantification (0.34~1.24 mg/L). The recoveries of antioxidants spiked to four food simulants ranged from 71.3% to 109.4%. The migrated antioxidants in this study were within the safety levels that resulted from the safety assessment by the estimated daily intake to the tolerable daily intake.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1145-1152
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• 2016

A construction post evaluation is introduced to provide information that can be used for similar construction projects in the future through the evaluation of the efficiency of a public construction project and the verification of the appropriateness of the project results. However, it is not widely used due to a lack of awareness of the method. For this reason, the aim of this study is to provide a basic frame that can be utilized as a reference for a similar project in the future based on the construction post evaluation. More specifically, a more effective analysis method for the construction post evaluation is proposed and then an exemplary analysis is performed based on the method. The paper analyzes 293 cases stored in construction CALS. Construction cost growth rates of railway projects are tend to be greater than other project types like highway, expressway, and harbour. Then, construction schedule grwoth rates of expressway are greater than others. This is expected to provide useful information for a future project, and serve as a basic frame. Moreover, it is also meaningful that a project can be analyzed from different perspectives through the construction post evaluation.