• 한국초등과학교육학회지:초등과학교육
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• 제28권3호
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• pp.277-291
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• 2009

This study is intended to develop plant inquiry instruction using Rapid-cycling Brassica rapa (RcBr) whose life cycle is relatively short, and to apply it to the elementary science instruction of the 4th grader and examine their plant concept, science inquiry skills and science-related attitudes. The materials were consisted of laboratory manuals for the students as well as teachers' guide. By observing the life cycle of RcBr, students can experience the conceptual learning of the plant's life cycle. In addition, this study investigated the cause of change in science inquiry skills and science-related attitudes by interviewing 12 students. It has shown that plant inquiry instruction using RcBr has meaningful effects on students' understanding of the plant concept, improving students' science inquiry skills, and changing students' science-related attitudes. Students who showed improvement in science inquiry skills were able to answer questions regarding science knowledge correctly. And students whose science related attitudes were improved had a positive attitude on cultivating RcBr. Students told that RcBr was an interesting and good material to inquire plant. Because of its small size and its relatively short life cycle of RcBR, it should be a desirable plant material for the inquiry instruction which can give rise to useful and meaningful results for the elementary school students.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2845-2849
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• 2008

Long Term Asset Management(LTAM) means a plan developed by using LCM(Life Cycle Management) process for optimum life cycle management of significant plant assets at each plant across the fleet. As a part of development of LTAM Strategies on nuclear turbines, a method so as to determine the future failure rates for low pressure turbine facilities at a nuclear plant was studied and developed by using both plant specific and industry-wide performance data. INPO's EPIX data were analyzed and some failure rate evaluation values considering preventive maintenance practices were calculated by using EPRI's PM Basis software. As the result, failure rate functions applicable to a priori and a posteriori replacement of low pressure turbines at a nuclear plant were developed and utilized in an assessment of economics of LCM alternatives on the nuclear turbine facilities in the respects of 40-year and 60-year operation bases.

• 정보교육학회논문지
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• 제17권3호
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• pp.357-365
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• 2013

본 논문의 목적은 4학년 과학 식물의 한살이 단원의 교육용 어플리케이션을 현재 교육과정에 기반을 두고 설계 및 구현하여, 교사가 수업과 과제활동에 직접적으로 편리하게 활용하고, 4학년 학생들의 식물 학습에 실질적인 도움을 주고자 하는 것이다. 이 어플리케이션을 활용하여 교사는 식물의 한살이 단원에서 오프라인 수업과 모바일 학습을 결합한 블렌디드 학습을 구현할 수 있고, 이를 통하여 학생들은 학교에서 배운 내용을 언제, 어디서든 복습하고, 어플리케이션을 이용하여 과제활동을 수행할 수 있다. 이와 같은 학습 방법은 학생들의 학습 동기를 증가시키고, 학습의 재미를 더하여 식물의 한살이 단원의 학습효과를 향상시킬 수 있을 것으로 기대된다.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2006년도 정기총회 및 제13회 학술대회 논문 초록
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• pp.64-64
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• 2006

• 동력기계공학회지
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• 제14권6호
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• pp.29-34
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• 2010

As the steam temperature of fossil power plant boiler is increasing, the use of 9Cr-1Mo high alloy material is prevalent and it is needed to investigate the characteristics of low cycle fatigue for high alloy and austenite stainless steel that has used up to recently. As a result of test, in 9Cr-1Mo high alloy steel, the relation of strain and fatigue life is non-linear and the crack mode of low cycle fatigue is brittle but in the austenite stainless steel, that of strain and fatigue life is linear and the crack mode of low cycle fatigue is ductile. Comparing the fatigue life between high alloy and austenite stainless steel, there is no consistent characteristics as to strains. But the fatigue life of 9Cr-1Mo steel is longer by 25% than that of STS304 stainless steel in the relatively low, 0.3% strain. In the other strain, the fatigue life of two materials is similar.

• 한국CDE학회논문집
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• 제12권3호
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• pp.191-199
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• 2007

In order to construct a data warehouse of process plant equipment, a classification structure should be defined first, identifying not only the equipment categories but also attributes of an each equipment to represent the specifications of equipment. ISO 15926 Process Plants is an international standard dealing with the life-cycle data of process plant facilities. From the viewpoints of defining classification structure, Part 2 data model and Reference Data Library (RDL) of ISO 15926 are seen to respectively provide standard syntactic structure and semantic vocabulary, facilitating the exchange and sharing of plant equipment's life-cycle data. Therefore, the equipment data warehouse with an ISO 15926-based classification structure has the advantage of easy integration among different engineering systems. This paper introduces ISO 15926 and then discusses how to define a classification structure with ISO 15926 Part 2 data model and RDL. Finally, we describe the development result of an ISO 15926-based classification structure for a variety of equipment consisting in the reactor coolant system (RCS) of APR 1400 nuclear plant.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.379-381
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• 1995

Many generating stations in korea are 25 years or more old, and are nearing the end of their planned life. Financial conditions and Site, Environment problems have made approval for construction of new stations increasingly difficult, and extending the life of an existing older plant may be a palatable alternative. Therefore, To determine whether generator rewinds are necessary to achieve an extended life, and Methods are required to estimate the proable remaining life of existing winding, here, We are going to estimate insolation condition through Nondestructive diagonostic test and Aging history tests of generator Stator winding and winding conditions through deterioration characteristics due to Heat cycle.

• The Plant Pathology Journal
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• 제38권4호
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• pp.372-382
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• 2022

Soybean is an important source of protein and for a wide range of agricultural, food, and industrial applications. Soybean is being affected by Xanthomonas citri pv. glycines, a causal pathogen of bacterial pustule disease, result in a reduction in yield and quality. Diverse microbial communities of plants are involved in various plant stresses is known. Therefore, we designed to investigate the microbial community differentiation depending on the infection of X. citri pv. glycines. The microbial community's abundance, diversity, and similarity showed a difference between infected and non-infected soybean. Microbiota community analysis, excluding X. citri pv. glycines, revealed that Pseudomonas spp. would increase the population of the infected soybean. Results of DESeq analyses suggested that energy metabolism, secondary metabolite, and TCA cycle metabolism were actively diverse in the non-infected soybeans. Additionally, Streptomyces bacillaris S8, an endophyte microbiota member, was nominated as a key microbe in the healthy soybeans. Genome analysis of S. bacillaris S8 presented that salinomycin may be the critical antibacterial metabolite. Our findings on the composition of soybean microbiota communities and the key strain information will contribute to developing biological control strategies against X. citri pv. glycines.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.696-697
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• 2015

Cost, schedule, and quality are the three major performance indicators for any construction project. Under the globalized competition in the nuclear industry, researchers and practitioners have also explored a systemized and integrated management system for cost, schedule, and quality. In order to address this issue, the concept of earned value management system (EVMS) has been often utilized. However, implementing EVMS for a mega-project of nuclear power plant (NPP) construction requires extensive overhead efforts. Though previous studies proposed structures and methods for effective NPP EVMS, there has been no legitimate study for data collection strategy for practical implementation. In this context, the purpose of this paper is to develop an effective data collection strategy for NPP EVMS. Firstly, the barriers to practical NPP EVMS were identified based on literature review and expert interviews. Strategies for data collection were then developed based on different phases of project life cycle. This study focuses on the 'life-cycle integrated progress management system' for NPP construction from an owner's perspective Therefore, results of this study can be used as a guide for preparing request for proposals (RFP) of an NPP owner organization.

• 인간식물환경학회지
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• 제24권4호
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• pp.355-363
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• 2021

Background and objective: This study was conducted on Forsythia velutina, a special plant, in Gyeongsangnam-do Arboretum under the Gyeongsangnam-do Forest Environment Research Institute, which is located in the southern part of Korea. Methods: The research aimed to analyze the flowering characteristics of the plant by calculating the optimal temperature and humidity according to the flowering time and flowering period for 8 years from 2010 to 2017 in order to provide basic data for bioclimate studies of endemic plants. Results: It was observed that the Forsythia velutina showed a life cycle from mid-March and to mid-November. Average growth period was 243 (± 6.5) days. In testing the reliability of a single variable according to the meteorological factors, the Cronbach's Alpha was 0.701, which indicates that the findings were relatively reliable. The average date of flowering was March 16 (SD = 5.8) and the average date on which blossoms fall was March 29 (SD = 5.2). A substantial difference in flowering period was observed from year to year 11 to 23 days, with an average of 16 days (± 4.7). The temperature and humidity in February to March, which affect the flowering, were 2.9-5.5℃, and 66.5-73.0%, respectively, and showed differences every year. Conclusion: The correlation between flowering time and meteorological factors was positive, and the highest daily temperature and average daily temperature had the highest significance. When establishing basic data on plant species for the conservation of endemic plants, the changes in life cycle events and weather conditions are identified. It is believed that it will be helpful in establishing a conservation strategy for the plant species in the future.