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Analysis of Problems and Improvement of Environmental Impact Assessment in Social-Economic Items Based on 19 Major Large Scale Development Projects (주요개발사업의 환경영향평가서 분석을 통한 사회경제항목평가의 문제점과 개선방안)

  • Lee, Sang-Don
    • Journal of Environmental Impact Assessment
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    • v.13 no.4
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    • pp.165-185
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    • 2004
  • Assessment in Socio-economic items should be used to estimate social influence when policies and projects were introduced. To estimate current situation of socio-economic items 19 Environmental Impact Statement (EIS) of large scale projects were analyzed. The projects were selected based on magnitude of social impact when the projects were implemented. Environmental Impact Statement was categorized into line projects(road construction, railroad construction, stream development, etc), and surface projects(energy development, wetland reclamation, recreation and sport development, and housing and residential development, etc) thus being chosen for 19 projects in each categories. This report was based on the analysis of 7 items in socio-economic environmental items(i.e., population, residents, industry, public facilities, education, transport and historical monument). Most EIS did not follow the regulation suggested by Ministry of Environment, and only current circumstances were briefly described. Indifference of in-depth analysis of socioeconomic environmental items would influence the process of social and environment impact negatively in the midst of construction of National Projects such as Outer Circle Seoul Highways, Saemankeum Reclamation Projects, etc. This abrupt halt of construction was mostly based on a lack of public hearing or public participation. Socio-economic items are also very much lacking in quantitative method and strengthening socio-economic environmental items is needed via checklist or matrix that brings decision-makers better ideas objectively.

The Effect of Factors such as Changes in the Degree of Difficulty of Concepts Presented in the Chemistry I Textbook, Changes in Class Types, etc. on Academic Achievement by Level

  • Min Ju Koo;Dong-Seon Shin;Jong Keun Park
    • International Journal of Advanced Culture Technology
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    • v.11 no.2
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    • pp.210-220
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    • 2023
  • We analyzed and compared factors such as changes in the degree of difficulty of concepts presented in Chemistry I textbook, changes in class types (non-face-to-face, face-to-face), etc. on academic achievement by level (upper, middle, and lower). Students from A high school in Gyeongsangnam-do were selected for the subjects of the study. As a result of analyzing the change in the degree of difficulty of concepts, the total score of chemistry I combined by non-face-to-face and face-to-face classes during the second semester was lower than that of the first semester. As a result of analyzing the impact of factors such as changes in conceptual difficulty, changes in class types, etc. on academic achievement by level, students' grades at the 'lower level' by non-face-to-face classes were lower than those by face-to-face classes. In particular, at the lower level of the second semester, there was a large difference in grades between non-face-to-face and face-to-face classes. In the results of these studies, it was found that instructors' active feedback is important to identify difficulties in understanding learning contents for students with low levels of academic achievement and improve them at the same time.

CFRP - New Material for Telescope Manufacturing

  • Kim, Young-Soo;Kim, Jihun;Song, Je Heon
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.81.3-81.3
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    • 2015
  • Carbon Fiber Re-enforced Polymer (CFRP) has replaced steel, especially for mobile devices. As CFRP is stiff and light-weight, it has been applied to airplane, sport car, golf clubs, semiconductor transporter, satellites, etc. In the telescope, the plastic material was introduced to the supporting tubes or rods connecting the primary mirror assembly and the secondary mirror structure. Nowadays, even the mirror itself is produced by CFRP. In this poster, material properties and production of CFRP telescopes are presented, and pros and cons are discussed.

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Computer integrated simulation of geometric features in 3 axis coordinate measuring machines

  • Pahk, Heui-Jae;Burdekin, M.;Peggs, G.
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1991.10a
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    • pp.379-401
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    • 1991
  • A comprehensive computer software has been implemented in conjunction with the software for volumetric error generator, to assess simulation on specific measurement tasks. The simulation algorithms have been developed for major measurement tasks, such as step gauge, ring gauge, sphere gauge, and cylinder gauge simulations etc. Verification and practical applications of the developed module have shown its efficiency and validity.

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Effect of Applied Voltage Bias on Electrochemical Migration in Eutectic SnPb Solder Alloy

  • Lee, Shin-Bok;Jung, Ja-Young;Yoo, Young-Ran;Park, Young-Bae;Kim, Young-Sik;Joo, Young-Chang
    • Corrosion Science and Technology
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    • v.6 no.6
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    • pp.282-285
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    • 2007
  • Smaller size and higher integration of electronic systems make narrower interconnect pitch not only in chip-level but also in package-level. Moreover electronic systems are required to operate in harsher conditions, that is, higher current / voltage, elevated temperature / humidity, and complex chemical contaminants. Under these severe circumstances, electronic components respond to applied voltages by electrochemically ionization of metals and conducting filament forms between anode and cathode across a nonmetallic medium. This phenomenon is called as the electrochemical migration. Many kinds of metal (Cu, Ag, SnPb, Sn etc) using in electronic packages are failed by ECM. Eutectic SnPb which is used in various electronic packaging structures, that is, printed circuit boards, plastic-encapsulated packages, organic display panels, and tape chip carriers, chip-on-films etc. And the material for soldering (eutectic SnPb) using in electronic package easily makes insulation failure by ECM. In real PCB system, not only metals but also many chemical species are included. And these chemical species act as resources of contamination. Model test systems were developed to characterize the migration phenomena without contamination effect. The serpentine-shape pattern was developed for analyzing relationship of applied voltage bias and failure lifetime by the temperature / humidity biased(THB) test.

Screen of Green Manure Crops for Cultivation on Agricultural Land with Spring Season in the Central Regions of Korea

  • Cho, Hyeon-Suk;Seo, Myung-Chul;Kim, Jun-Hwan;Sang, Wan-gyu;Shin, Pyeong;Lee, Geon Hwi
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.6
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    • pp.689-696
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    • 2015
  • The green manure crops are returned to soil when the plants are still green. The green manure crops play a role in reducing chemical fertilizers, improvement of soil fertility, reduction of soil erosion, weed control, and landscapes effect. Typical green manure crops are barley green manure, hairy vetch, chines milk vetch and clovers. We sowed 49 species of green manure crops in upland soil to increase the usage of green manure crops. We searched the effectiveness of green manure yield, C/N ratio, soil mulching, and landscape effect. The green manure crops that have $5tonha^{-1}$ or more of green manure yield (fresh weight) were 6 gramineous crops, 4 leguminous crops, and 3 others. Green manures yield in a short growth period was higher in gramineous crops than leguminous crops. Among the green manure crops, 3 gramineous crops, 12 leguminous crops, and 3 others were under 25 in C/N ratio. Seven gramineous crops, 8 leguminous crops, and 5 others were over 50% of soil covering rate. Green manure crops that have beautiful flowers were in total 16 kinds, such as 4 gramineous crops, 6 leguminous crops, and 6 others. In result, based on green manure yield and C/N ratio, excellent species in the green manure crops were 4 species (triticale, 2 kinds of hairy vetch, and lupin). Green manure crops that were effective at soil mulching were 20 species, like hairy vetch, oats, sorghum, phacelia, buckwheat, etc. Buckwheat, crotalaria, mustard plant, phacelia, and etc. could be available for landscape crops.

An Analysis on the Satisfaction of Service Quality for Seasonal Arboretum Visitors using IPA (IPA를 이용한 계절별 국립수목원 이용객의 서비스 질 만족도 연구)

  • Lee, Hyo-jung;Kim, Jae-Hyun;Lim, Yun-jung;Chang, Chu-youn;Tae, Yoo-lee;Hong, Sung-Kwon
    • Journal of Korean Society of Forest Science
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    • v.100 no.4
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    • pp.650-663
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    • 2011
  • The purpose of this study was to investigate the satisfaction of service quality for seasonal visitors of Korea National Arboretum using Importance-performance analysis. Data were obtained from visitors of Korea National Arboretum on spring, summer, autumn. Results of analysis showed that all season visitor's satisfaction was high. The IPA was undertaken with total 24 variables about service quality of arboretum. Results of IPA was founded that summer visitors want to improve some services (information facilities, forest museum, conveniences, etc). Autumn visitors, on the other hand, thought that some services (kindness, active responsiveness, variety of plant, etc) are overinvested. As a results, there is differences between importance and satisfaction about seasonal service quality.

Blood and milk metabolites of Holstein dairy cattle for the development of objective indicators of a subacute ruminal acidosis

  • Hyun Sang Kim;Jun Sik Eom;Shin Ja Lee;Youyoung Choi;Seong Uk Jo;Sang Suk Lee;Eun Tae Kim;Sung Sill Lee
    • Animal Bioscience
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    • v.36 no.8
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    • pp.1199-1208
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    • 2023
  • Objective: The purpose of this study was to perform a comparative analysis of metabolite levels in serum and milk obtained from cows fed on different concentrate to forage feed ratios. Methods: Eight lactating Holstein cows were divided into two groups: a high forage ratio diet (HF; 80% Italian ryegrass and 20% concentrate of daily intake of dry matter) group and a high concentrate diet (HC; 20% Italian ryegrass and 80% concentrate) group. Blood was collected from the jugular vein, and milk was sampled using a milking machine. Metabolite levels in serum and milk were estimated using proton nuclear magnetic resonance and subjected to qualitative and quantitative analyses performed using Chenomx 8.4. For statistical analysis, Student's t-test and multivariate analysis were performed using Metaboanalyst 4.0. Results: In the principal component analysis, a clear distinction between the two groups regarding milk metabolites while serum metabolites were shown in similar. In serum, 95 metabolites were identified, and 13 metabolites (include leucine, lactulose, glucose, betaine, etc.) showed significant differences between the two groups. In milk, 122 metabolites were identified, and 20 metabolites (include urea, carnitine, acetate, butyrate, arabinitol, etc.) showed significant differences. Conclusion: Our results show that different concentrate to forage feed ratios impact the metabolite levels in the serum and milk of lactating Holstein cows. A higher number of metabolites in milk, including those associated with milk fat synthesis and the presence of Escherichia coli in the rumen, differed between the two groups compared to that in the serum. The results of this study provide a useful insight into the metabolites associated with different concentrate to forge feed ratios in cows and may aid in the search for potential biomarkers for subacute ruminal acidosis.

Consideration of Programs and Operations of Farms Providing Agro-Healing Service

  • Lee, Sang Mi;Jeong, Na Ra;Jeong, Seon Hee;Gim, Gyung Mee;Han, Kyung Sook;Chea, Young;Kim, Kwang Jin;Jang, Hyun Jin
    • Journal of People, Plants, and Environment
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    • v.22 no.1
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    • pp.1-14
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    • 2019
  • This study was designed to examine agro-healing services and programs provided and operated by farms in Korea. The results of the analysis of the agro-healing programs and operation of farms were as follows. The purpose of the operation of farms was to raise productivity by managing farms in a cooperative way through agricultural production, education and healing, and to raise income by processing and selling agricultural products. It was difficult to access farms by public transport and thus visitors had to use their own cars. The size of farms varied. The main resources utilized in the surveyed programs were plants, rural environments and landscapes, and agricultural products. The programs were conducted using resources that were commonly found in rural areas. Facilities on each farm were equipped with facilities (indoor and outdoor learning place, gardens, vegetable gardens, orchards, etc.) and convenience facilities (parking lots, drinking fountains, kiosks, etc.) to support program operation. However, facilities for the handicapped and accommodation facilities were insufficient. The programs operated on each farm utilized agricultural resources, farm produce, and rural resources and were classified into activities such as making, feeling, and growing. The average number of people who operated the family-centered program was 2-3, having qualifications such as welfare horticultural therapists, forest interpreters, experience instructors, and social workers. In addition, they had expertise in medicinal food, dietary life, and social welfare, and they also had essential expertise required to operate programs.

The effect of pre-service science teachers' experiences in nuclear physics research on their understanding of scientific inquiry process and career planning (핵물리 연구 참여 경험이 예비 과학교사의 과학 탐구과정의 본성에 대한 인식과 진로탐색에 미치는 영향)

  • Lee, In-Sun;Choi, Kyung-Hee;Hahn, In-Sik;Kim, Seon-Hwa;Lee, Hyun-Ju
    • Journal of The Korean Association For Science Education
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    • v.29 no.5
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    • pp.541-551
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    • 2009
  • This study aimed to investigate the effect of pre-service science teachers' experiences in nuclear physics research on their understanding of scientific inquiry process and career planning. The thirty-week URP (Undergraduate Research Participation) program was designed with the participation of six pre-service science teachers. Data sources included in-depth interviews with the individual teachers, group discussions, participant observations with field notes over the weeks, journals and lab logs, etc. Results indicated that the teachers perceived the complex and repetitive nature of the science research process, the importance of scientists' creativity and collaboration, etc. Their typical impressions of scientists has also more or less changed. In addition, the teachers had opportunities to confirm their aptitude in physics and to explore their career options in physics-related fields.