• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.739-745
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• 2011

This study was performed to investigate the enrichment of resveratrol content in harvested grapes using the modulation of cell metabolism with ultra-violet (UV) irradiation. Resveratrol, a phytoalexin, is produced by stilbene synthase (STSY) from malonyl-CoA and ${\rho}$-coumaroyl-CoA. Its biosynthesis has been reported to be induced by UV and other environmental factors. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed that STSY Promoter 1 in grapes was very highly expressed by treatment with UV. Grapes were harvested and treated for post-harvest induction of STSY gene expression with UV, and then their resveratrol content was analyzed. UV treatment for 5 minutes provided the best condition for the induction of STSY gene expression. When harvested Gerbong and MBA grapes were treated with a prototype UV radiator, their resveratrol content was enriched upto 5 times compared with untreated grapes. These results suggest that a post-harvest UV treatment can be applied to enrich resveratrol content in grapes and add value to them.

• Journal of Digital Contents Society
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• v.12 no.4
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• pp.601-609
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• 2011

In developing countries, economically under-privileged are mostly consisted of women, therefore supporting those women signify supporting the local society and the family. Advancement of women's economic status not only contributes to her family but also to the local society, nation, and to the global world as a whole. This paper is a research on local informatization and successful model in e-business for Indonesia, which established interactive research model networking with Korea-Indonesia Research Institution and policy-makers for two years and susggested practical research model through visiting Pekalongan. Through activated interaction between women enterprises and policy makers from Korea and Indonesia, the research paper seeks to create research based network and provide opportunities of information access and business matching to local informatized and e-business enterprises. In research adopted regions, city development project has been accomplished in human, business and environmental field since 2005, and have selected Pekalongan region where infra is settled to certain extent. With the information about Indonesia's city development project, investigation on Pekalongan's current geographical, humanistic status quo, the paper aims to and create Indonesian female e-business professionals, e-business user, e-business producers and provide successful model on Pekalongan's local informatization and e-business.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.77-77
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• 2013

최근의 산업활동에서는 신규 원료 개발과 생산 효율성을 높이기 위하여 분체 공정이 증가하고 있는데, 미세 분진의 취급으로 분진운의 형성과 착화가 용이해지므로 분진폭발이나 화재 위험성이 증가하고 있다. 분진을 안전하게 사용하고 저장, 취급하기 위해서는 착화 전의 위험성 지표로서 최저발화온도(MIT ; Minimum Ignition Temperature)를 사전에 파악해 두는 것이 중요하다. 분진농도의 발화온도는 장치 내의 발화위험성이나 분진 취급 공정의 사고예방대책 관리를 위한 실용적 관점에서 중요하게 활용되는 폭발특성값이다. 또한 분진의 발화온도는 분진농도에 의존하며 농도변화에 따른 가장 낮은 온도를 MIT라고 한다. 본 연구에서는 화재폭발사고 빈도가 줄지 않고 있는 Mg 및 Mg-Al합금(60:40 wt%, 50:50 wt%, 40:60 wt%)을 대상으로 조성비율에 따른 최저발화온도를 실험적으로 조사하였다. Mg 및 Mg-Al(60:40 wt%), Mg-Al(50:50 wt%), Mg-Al(40:60 wt%) 시료의 평균입경은 142, 160, 151, $152{\mu}m$이다. MIT실험장치는 IEC 61241-2-1(Methods for Determining the Minimum Ignition Temperatures of Dust, 1994)에 준거하여 제작하여 사용하였다. 실험장치는 가열로, 분진운 시료홀더, 온도조절장치, 압축공기 제어장치 등으로 구성되어 있다. 구체적인 실험방법은 시험분진를 분진홀더에 장착하고 0.5 bar의 압축공기를 0.3 sec 동안 사용하여 일정 온도로 가열된 로의 내부로 분진운을 부유시킬 때에 분진운이 발화하여 가열로 하단부의 개방구에까지 화염이 전파하는지를 디지털비데오카메라로 기록, 평가하여 발화 유무를 판정하였다. Mg합금에 대한 MIT를 측정한 결과 $740^{\circ}C$가 얻어졌으며, Mg-Al(60:40 wt%)의 MIT는 $820^{\circ}C$로 조사되었다. 그러나 Mg-Al(50:50 wt%) 및 Mg-Al(40:60 wt%)에 대해서는 최대 가열로의 설정온도를 $890^{\circ}C$까지로 하여 농도를 변화시키면서 조사하였으나 발화가 일어나지 않았다. 문헌에 따르면 Mg입자 표면의 산화피막은 다공성으로 일정 온도에서 산화반응이 시간에 따라 직선적으로 증가하는데 반하여, Al의 산화피막은 보호 작용을 하여 일정 온도에서 산화반응속도가 표면과 내부의 농도 기울기에 의한 확산속도에 의존한다고 보고하고 있다. 본 연구결과를 토대로 Mg-Al합금의 발화특성을 고찰해 보면, Mg-Al합금에서 자기 전파성이 작은 Al성분의 증가는 착화지연이 증가하여 연소성이 감소하여 최저발화온도의 증가로 이어지는 것으로 추정되었다. 또한 발화온도는 주어진 조건의 온도장에서 분진이 존재하는 시간 길이에 따라 변화하므로, 발화온도를 실험적으로 측정하는 경우에는 측정장치나 방법에 따라 달라지므로 사업장의 현장에 발화온도를 적용하는 경우에는 장치 내의 분진의 존재시간을 고려할 필요가 있다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.120-120
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• 2010

에너지 절약적 차원에서 한 대의 실외기에 다수의 실내기가 접속되는 개별공조형 멀티 열펌프에 관한 연구 및 개발과 보급이 증대되고 있다. 본 연구에서는 복수의 실내기를 갖고 가변속 압축기를 채용한 지열원 물대공기 멀티열펌프시스템을 학교 현장에 설치하여 제조사의 운전 제어 알고리즘에 따라 일일 냉난방 실증 성능 특성을 분석하였다. 2008년 9월 30일의 냉방부하가 낮은 일자에 대하여 시간에 따른 부하 변동에 따라 압축기의 용량가변으로 실내기 냉방용량은 정격용량 대비 17.1%에서 111.3%의 범위에서 변이되었으나, 열펌프 유닛의 일일 최대 COP는 6.2를 나타냈으며, 일일 평균 열펌프 유닛 COP는 4.5로 열펌프 유닛 인증 기준 이상의 성능을 나타냈다. 2008년 11월 10일 대비 2008년 12월 15일에는 시스템 가동 중의 평균 외기온도가 $9.6^{\circ}C$ 감소하였으나, 각 재실공간의 용도별 부분 부하특성으로 11월 10일 보다 난방 부하량이 작게 나타났다. 하지만, 12월 15일에는 부하량이 매우 작아서 11월 10일보다 잦은 압축기 가변에 따른 손실로 일일 평균 COP가 낮게 나타났다. 2009년 1월 12일에는 정격 용량대비 94%의 부하율로 11월 10일과 12월 15일 대비 4배 이상의 부하량으로 압축기 용량 가변율이 작아서 난방용량과 COP 변화율이 작게 나타났다. 2009년 1월 12일에는 지중순환수의 실외열교환기 유입온도가 2008년 12월 15일보다 감소하고, 시스템의 난방용량 증가로 상대적으로 응축기와 증발기 크기가 감소한 효과로 히트펌프 유닛 COP가 감소하였으나, 본 지열원 열펌프 제조사에서 생산하고 있는 본 지열원 시스템과 동일한 압축기 등을 채용한 동일 용량의 공기열원 열펌프의 1월 12일 외기온도 $-10^{\circ}C$에서의 열펌프 유닛 COP 대비 70% 우수한 성능을 나타냈다. 본 지열원 히트펌프의 2008년 11월 10일의 일일 평균 히트펌프 유닛 COP는 외기온도가 낮고 일일 부하량이 크게 나타난 1월 12일의 일일 평균 히트펌프 유닛 COP 대비 37% 높게 나타났으나, 지중순환펌프의 정속운전으로 시스템 요구 지중순환수 유량 증가에 따른 성능 향상보다 소비전력 증가 영향이 커서 1월 12일의 시스템 COP 보다 33.3% 작은 값을 나타냈다. 본 연구의 용량 가변형 압축기를 채용한 지열원 멀티 히트펌프 유닛을 지열원 냉난방 시스템의 히트펌프 유닛으로 사용할 경우 시스템 최적화를 통한 시스템 COP 향상과 연간에너지 절감을 이루기 위해서는 히트펌프의 용량 변화 시에 지중순환펌프의 순환 유량 최적화를 위한 효율적 운전 제어 알고리즘 개발이 요구된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.482-489
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• 2020

This study conducted a prototype development and evaluation by performing die-casting mold design, mold manufacturing, and injection condition optimization based on flow and solidification analysis to meet the needs of the coupling parts produced by die casting. Through flow analysis, the injection conditions suitable for 100% filling in the cavity were found to be a molten metal temperature of 670 ℃, injection speed of 1.164 m/s, and filling pressure of 6.324~18.77 MPa. In addition, solidification close to 100 % occurred in all four cavities when the solidification rate was 69.47 %. A defect inspection on the surface and inside the product revealed defects, such as poor molding and pores. In addition, the dimensions of the injected product were within the target tolerance and showed good results. Through the feedback of the results of flow and solidification analysis, it was possible to optimize the mold design, and the injection optimization conditions were confirmed to be a total cycle time of approximately 6.5 seconds. Good quality carrier parts with an average surface hardness of approximately 45 mm from the gate measured at 97.48(Hv) could be produced.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.1
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• pp.1-12
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• 2020

As one of the essential resources in the agricultural process, soil moisture has been carefully managed by predicting future changes and deficits. In recent years, statistics and machine learning based approach to predict soil moisture has been preferred in academia for its generalizability and ease of use in the field. However, little is known that machine learning based soil moisture prediction is applicable in the situation of South Korea. In this sense, this paper aims to examine 1) whether publicly available weather data generated in South Korea has sufficient quality to predict soil moisture, 2) which machine learning algorithm would perform best in the situation of South Korea, and 3) whether a single machine learning model could be generally applicable in various regions. We used various machine learning methods such as Support Vector Machines (SVM), Random Forest (RF), Extremely Randomized Trees (ET), Gradient Boosting Machines (GBM), and Deep Feedforward Network (DFN) to predict future soil moisture in Andong, Boseong, Cheolwon, Suncheon region with open source weather data. As a result, GBM model showed the lowest prediction error in every data set we used (R squared: 0.96, RMSE: 1.8). Furthermore, GBM showed the lowest variance of prediction error between regions which indicates it has the highest generalizability.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.7
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• pp.58-65
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• 2019

Polymer concrete is expected to be widely used as a building material because it has a shorter hardening time and excellent compression, tensile, bending, bond strength, frictional resistance and abrasion loss compared to general concrete. The polymer concrete has excellent vibration damping performance and research on the use of various reinforcing materials is being conducted. However, in order to completely replace the general concrete and the general anti-vibration reinforcement, such polymer concrete requires an overall review of vibration reduction performance considering physical properties, dynamic properties, productivity and field applicability. In this study, the physical and dynamic properties of polymer concrete by epoxy mixing ratio were compared with those of general concrete. It was appeared that compression, tensile, bending and bond strengths of polymer concrete by epoxy mixing were significantly higher than those of general concrete. Especially, the tensile strength was more than 4 ~ 6.5 times. Based on the basic physical properties of polymer concrete, the damping ratio, which is a dynamic characteristic according to the epoxy mixing ratio, was derived through analytical models and experiments. As a result, the dynamic stiffness of polymer concrete was 20% higher than that of general concrete and the loss rate was about 3 times higher.

• Journal of the Korean Institute of Gas
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• v.22 no.3
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• pp.74-83
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• 2018

Anyone who wants to install local ventilation system must obtain a permission from the Ministry of Employment and Labor even if he has permission from the Ministry of Environment. This is because not only the Atmospheric Environmental Protection Act, but also the manufacturing industry's hazardous risk prevention plan under Article 48 Clause 2 of the Industrial Safety and Health Act is to be submitted by 15 days before the construction. Under the current Environmental Protection Act, the Ministry of Environment regulates only the emission of pollutants from local exhaust ventilation systems into the atmosphere and the contents of workers' safety and health within industrial sites are managed by the Ministry of Employment and Labor. Even with the approval of the Ministry of Environment, the number of unsuccessful cases by the Ministry of Employment and Labor has increased, causing a growing discontent among the sites due to production delays and additional costs of improvement. In addition, local exhaust systems that are at greater risk of fire explosion have increased the risk of severe industrial accidents due to fire explosion. This is due to insufficient design of air volume, control speed, return speed, duct size, and risk of fire explosion. This is because the criteria and procedures for approval of local exhaust ventilation systems are similar, but the Industrial Safety and Health Act adds additional screening items for safety and safety of workers and fire and explosion. In this study, the Environment Ministry and the Employment and Labor Ministry seek to find a reasonable way to operate the system by comparing local exhaust ventilation system installation approval standards.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.3
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• pp.63-76
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• 2016

The purpose of this study was to develop index about the sixth industrial entrepreneurs to establish the spirit and measuring the sixth industrial entrepreneurship for groups successfully led to the sixth industry of agriculture, which is actively being conducted in recent years aimed at rural stimulate the economy. Enlighten the value of rural resources, production, processing, in a sixth industry establishment that has a characteristic of fusion distribution and tourism in addition to the elements of the entrepreneurship that has been emphasized in the traditional establishment, the more diverse entrepreneurship element has been requested. In this study, to derive the traditional entrepreneurship of the components and the sixth industry entrepreneurship component through literature research, through interviews with experts of the sixth industry, an important element of the entrepreneurship that is required in the field It was derived. Based on the derived results, set the index of the sixth industry entrepreneurship, it was conducted a questionnaire survey of sixth industry workers. Through analysis of the navigation factors, to evaluate the measurement and indicators of relevance, factors that have been set through the results literature study and interviews of exploratory factor analysis it was found that has been rationally constructed. The results of this study, education and consulting for the activation of the sixth industry, would be able to take advantage of, such as in the planning of education programs for whom decide to go back to the countryside(Agro migration). In addition, to diagnose the entrepreneurship of a conventional sixth industry progress mainly, it is expected to be able to help you to proceed with the custom capability development that meets the individual needs.

• Journal of Korean Library and Information Science Society
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• v.50 no.4
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• pp.539-559
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• 2019

One of the fundamental roles of libraries is to provide users with efficient and easy retrieval of materials. Various discussions have been made at domestic and abroad to improve the accessibility of materials by category, user, and collection, and at the center of this is the issue of improving classification and cataloging systems. However, there are few studies in this area dealing with the data accessibility of the DLS catalog, which is a central tool for accessing domestic school library materials. This study started from the appeal of school library users to the difficulty of searching and accessing books, especially literature. This study is an exploratory study that attempts to derive problems by finding the causes of there difficulties from various aspects. To this study, we surveyed and analyzed the current status of school library collections, the data registration of the school library support system DLS, the subject accessibility of catalog records produced through this, and the recognition and opinions of school library professionals. As a result, school library collections were highly concentrated in the literature field, and it was found that there was not enough catalog bibliographic records to provide efficient access to these collections. In addition, it was found to be somewhat lacking through the DLS search function to compensate for this. Surveys of school librarians and librarians have also identified this problem, and a rich topic index and search keyword assignments have been drawn to the majority of opinions as a way to improve access to materials in school library catalogs. As a continuous discussion on this subject, the plan for improving access to school library materials will be more concrete through future user studies and new challenges for bookshelf classification.