방사선조사에 의한 한국산어류의 품질보존에 관한 연구 : Ⅰ. 민어 , 참조기 및 물가자미의 감마선 조사 후의 보존특성 Ⅰ. Radurization of croaker , yellow corvenia and roundnose flounder

이민철,정종락,김수일 한국수산학회 1976 한국수산과학회지 Vol.9 No.2

민어 (croaker-Nibea imbricata, Matsubara), 참조기 (yellow corvenia-Pseudosciaena manchurica, Jordan and Thompson) 그리고 물가자미(roundnose flounder-Xystrias grigorjewi, Herzenstein) 어육을 0.5 Mrad이하의 감마선량에 조사하여 냉장기간중의 선도 유지기간 연장을 가져오는 최적 조사선량을 구하였다. 조사된 어육을 0˚와 5℃에 35일간 저장하는 동안에 일어나는 관능학적 변화를 미생물학적, 화학적 변화와 비교 검토하였다. 0℃ 저장을 위한 민어와 참조기의 최적선량은 0.1 Mrad였으며 5℃ 저장에서는 0.2 Mrad였다. 물가자미는 방사선 조사에 대단히 민감하여 0˚와 5℃ 다같이 0.1 Mrad였다. 각각의 최적선량에 조사 처리하므로써 민어의 경우 0℃에서는 선도 유지기간이 비 조사구의 2주간에서 5주간(3-4배)으로 연장되었으며 5℃에서는 역시 1주간 이내에서 4주간(4-5배)으로 연장이 가능하였다. 참조기는 0℃에서는 3∼4배로, 5℃에서는 4-5배로 그리고 물가자미는 0℃에서 4-5배, 5℃에서 6-7배로 각각 연장되었다. Optimum doses The optimum dose that may be defined as the dose below the maximum permissible dose, yet would bring about a significant storage life extension at refrigerated temperatures, varied with species of fish as well as with the postirradiation storage temperatures. Thus the dose of 0.1 Mrad was considered to be optimum for the croaker and yellow corvenia at 0℃, while at 5℃ the dose of 0.2 Mrad would be suitable for both species. The roundnose flounder was more radiosensitive and even at the dose of 0.1 Mrad a slight irradiation odor was detected immediately after the radiation treatment. Such degree of irradiation odor disappeared upon stoage, therefore, the dose of 0.1 Mrad was considered to be optimum for the roundnose flounder at both 0˚and 5℃. Storage life extension The croaker meats irradiated at 0.1 Mrad could be held at 0℃ as long as 5 weeks in good acceptable conditions, while the unirradiated control became unacceptable within 2 weeks-3-4 for extension of storage life at 0℃. At the storage temperature of 5℃, the storage life of 0.2 Mrad irradiated samples was extended from less than one week to 4 weeks-4-5 fold extension. The storage life extension of 0.1 Mrad irradiated yellow corvenia at 0℃ was from less than 2 weeks for the unirradiated to 4 weeks-approximately 2-3 folds and that of 0.2 Mrad irradiated samples stored at 5℃ was from 5 days to 3 weeks 4-5 folds. The roundnose flounder meats irradiated at 0.1 Mrad could be held at 0℃ for 3-4 weeks as compared to less than 1 week for the unirradiated and at 5℃ the storage life could be extended from less than 3 days to up to 2 weeks. Thus the storage life extension by 4-5 folds and by 6-7 folds was possible at 0˚and 5℃ storage, respectively. Postirradiation storage microbiology and biochemistry In general 10 fold reduction of initial microflora was realized as a result of irradiating fish samples at 0.1 Mrad. The extent of microflora reduction increased with increasing doses applied, but not proportionately dependent. The microbial growth in the irradiated was severely retarded during the subsequent storage period, lagging far behind that of the unirradiated control samples except in the late storage phase, when the levels of microflora of the irradiated either approached to or rose above the levels of the unirradiated. The microbiological changes caused by irradiation was reflected in the pronounced suppression of TVB and TMA accumulation during the storage period. This suggests that irradiation treatment brought about both quantitative and qualitative changes in microflora initially present and it is reasonable to suggest that the microflora removed by irradiation in fact represent most of the flora capable of producing TVB and TMA in normal fish spoilage process.

국방규격 개선사업의 성과평가모형 개발 및 적용방안 연구

이민철,김영현,안영준,김준수 한국품질경영학회 2023 품질경영학회지 Vol.51 No.2

Purpose: The purpose of this study is to identify key performance evaluation items and factors that are effective and practical for project management of defense standard standard improvement projects, and to develop a quantitative performance evaluation model. Methods: For the development of a performance evaluation model for defense standard improvement projects, we analyzed past major project performance and derived evaluation items and factors. To increase the objectivity and efficiency of project evaluation, we developed an evaluation index that enables relative evaluation of evaluation targets, and calculated the main importance of evaluation items using the Analytic Hierarchy Process (AHP) method based on the main opinions of expert groups. Results: The study resulted in the identification of main performance items for defense standard improvement projects, which were classified into defense standard conformity review performance and defense standard improvement performance items. We also simplified the evaluation model by integrating various evaluation items into similar evaluation factors. Additionally, we developed a quantitative evaluation index that enables relative evaluation of the targets and verified the objectivity and validity of the suggested performance evaluation model by reevaluating it using performance data from past commissioned professional institutions Conclusion: Developing a quantitative evaluation model for defense standard improvement projects is expected to provide a means of measuring the effectiveness of the project, and to be used as a tool to determine the appropriateness and effectiveness of medium and long-term project plans.

Effects of Majorana bound states on dissipation and charging in a quantum resistor-capacitor circuit

이민철 한국물리학회 2019 Current Applied Physics Vol.19 No.3

We investigate the effects of Majorana bound states on the ac response of a quantum resistor-capacitor circuit which is composed of a topological superconducting wire whose two ends are tunnel-coupled to a lead and a spinless quantum dot, respectively. The Majorana states formed at the two ends of the wire are found to suppress completely or enhance greatly the dissipation, depending on the strength of the overlap between two Majorana modes and/or the dot level. We compare the relaxation resistance and the quantum capacitance of the system with those of non-Majorana counterparts to find that the effects of the Majorana state on the ac response are genuine and cannot be reproduced in ordinary fermionic systems.

레이다처리장치 시험장비의 데이터 처리방안

이민철,김용민 한국군사과학기술학회 2018 한국군사과학기술학회지 Vol.21 No.6

To develop and check a Radar Processor Unit, checking the function and performance of the requirement is very important factor in developing Radar. General methods for verifying the Radar is simulation test, environment linkage test and field operation test, firstly, in case of requirement analysis phase, verify Radar algorithm and design by using mathematical method based simulation test method, and secondly, in case of unit test and integrated test phase, Test Equipment is set to simulate radar environment in the lab to verify radar function and performance. Lastly, field operation test phase is carried out to confirm the function and performance after it is mounted on the actual equipment. To successfully develop Radar Processor Unit, using the method of field operation test method after sufficient test cases are tested in radar environmental interlocking method in order to save cost and testing period and because of this reason, development of the Radar Processor Unit Test Equipment is becoming very important factor. In this paper, we introduce the concept of test equipment development and important factors in test equipment, which are target simulation, data processing and device interlocking.

Thermal and mechanical properties of TPU and Glassfiber/Silane coupling agent on silica/PP composite for filter module part

이민철,김영곤,김영선,심상은 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

Filter module systems can be used for waste water treatment, recovery of fibers, filtration of metallic salt solutions and so on. Suport tray materials are wood, metal and rubber. These elements are showing a lot of disadventages as for example corrosion resistance and bad sealing. However Polypropylene turned out to be the best material due to pricepower- performance.Thermoplastic polyurethane(TPU) was employed as filter membrane. Their parts were also thoroughly investigated in terms of tensile properties, flexural perperties, durability against dynamic mechanical movement, thermal stability and so on.

단위학교 교육정보화 정책의 의사결정 유형 분석

이민철,김홍래,Lee, Min-Cheol,Kim, Hong-Rae 한국정보교육학회 2010 정보교육학회논문지 Vol.14 No.2

According to the school autonomy plan on April 15, 2008, schools have a responsibility for ICT in education policy. Because of this plan, A guideline for governmental action for ICT education was repealed, on the contrary, responsibilities for ICT education in school level has increased. The radical exchange of education policy has a big impact on decision-making about ICT in education policy in school level. Consequently, the digital divide is generated between students, teachers and schools. So, this paper is intended as an investigation of decision-making types and awareness of teachers about ICT in education policy in elementary school. And this paper presents new ideas for decision-making of ICT policy in elementary schools. 2008년 4월 15일 학교 자율화 계획에 따라, ICT 교육에 대한 국가 수준의 지침은 폐지되었으며, 오히려 학교 수준에서 ICT교육에 대한 책임이 더욱 커지게 되었다. 이와 같은 교육정책의 급격한 변화는 단위학교 수준에서 ICT 교육 정책에 대한 의사결정에 큰 영향을 미치게 되었다. 그 결과로서 학생, 교사, 학교 간의 디지털 격차가 발생하게 될 가능성이 높아졌다. 따라서 본 연구는 단위학교 수준에서 ICT 교육정책에 대한 의사결정 유형과 인식에 대하여 조사하였다. 그리고 초등학교에서 ICT 교육정책 의사결정을 위한 새로운 의견을 제시하였다

새로운 분할법에 의한 평면 및 곡면의 삼각형 요소망 자동생성 ( Triangular Mesh Generation on Planes or Surfaces by a New Looping Method )

이민철,전만수 대한기계학회 1998 대한기계학회 춘추학술대회 Vol.- No.-

공공조달 참여와 기업성장: 기업연령의 조절효과를 중심으로

이민철,정태현 기술경영경제학회 2021 Journal of Technology Innovation Vol.29 No.3

The importance of industrial policy and innovation policy perspectives on public procurement has recently been highlighted. In particular, there have been discussions and studies on whether public procurement directly affects the growth and innovation of SMEs. As an extension of this study, this study analyzes whether the age of a firm moderating the effect of public procurement on growth among the characteristics of firms participating in public procurement. The analysis data was constructed by matching the financial data of about 1,247 firms designated as excellent products by the Public Procurement Service(PPS) from 2006 to 2017 and the public procurement sales. As a result of analysis through the panel regression model, firms with a greater degree of public procurement showed a higher growth rate, and this relationship was stronger with younger firms. This result not only contributes to the existing academic discussion on the effectiveness of public procurement, but also has significance in the establishment of public procurement policy. 공공조달에 대한 산업정책과 혁신정책 관점의 중요성이 최근 부각되고 있다. 특히, 공공조달이 중소기업의 성장과 혁신에 직접 영향을 끼치는지에 대한 논의와 연구가 있어 왔다. 이러한 연구의 연장선상에서, 본 연구는 공공조달에 참여하는 기업의 특성 중 기업의 연령이 성장에 대한 공공조달의 효과를 조절하는지를 분석한다. 분석 자료는 2006년부터 2017년까지 조달청 우수제품으로 지정된 약 1,247개 기업의 재무적 성과와 공공조달 매출 성과를 연계하여 구축하였다. 패널회귀모형을 통해 분석한 결과, 공공조달 참여 정도가 큰 기업일수록 높은 성장률을 보였을 뿐만 아니라, 이 관계는 젊은 기업일수록 더 강하게 나타났다. 이 결과는 공공조달의 효과에 대한 기존 학술적 논의에 기여할 뿐만 아니라 공공조달 정책 수립에 있어서도 의의를 가진다.

Estrogen과 Progesteron이 Ureaplasma urealyticum의 증식과 세포 부착성에 미치는 영향

이민철,장명웅 고신대학교(의대) 고신대학교 의과대학 학술지 1989 고신대학교 의과대학 학술지 Vol.5 No.1

Many investigators have suggested that hormonal status are closely related with colonization rates of Ureaplasma urealyticum(U.urealyticum) in female genital tract, but some investigators do not agree with this view. The present study was undertaken to test the significance of estrogen and progesterone acting as either stimulant or inhibitor on growth and adherence of U.urealyticum to FL cell in minimum essential medium,(MEM) and ureaplasma standard liquid medium 10-B media. U.urealyticum T960 strain and human amniotic fibroblast(FL) cells were used in this study. U.urealyticum was cultured in a 10-B medium formulated by Shepard and Lunceford. FL cells were cultured in complete MEM supplemented by in dose of 10% fetal calf serum and suitable antibiotics. Estrogen was supplemented with 0.06ng, 0.6ng, 6.0ng or 60.0ng per ml and progesterone in dose of 0.1ng, 1.0ng, 10.0ng, or 100.0ng per ml in 10-B or MEM media or FL cell culture system. U.urealyticum was inoculated into 10ml of new 10-B or MEM media containing different concentrations or estrogen or progesterone, and incubated at 37℃ for 30 hours. At every 6 hour interval, the bacterial number in the culture fluid was calculated by color changing unit(CCU). The CCU of culture fluid was determined by making serial ten-fold dilutions up to 10¹² in duplicates with 10-B media. The highest dilution at which one of the two media changed from yellow to red was considered to contain 50% color changing unit. The 90ml of FL cell suspension(10⁶) were divided into 9 portions, and were added different concentration of estrogen and progesterone in each portion, then a 0.1 ml of U.urealyticum culture fluid was added in it. After, each portion was divided into 1 ml and placed in 24 well culture plate, then incubated at 37℃ for 72 hours. Bacterial number in the culture supernatant and adhered to cell were calculated same as mentioned above. The results of this study are summarized as follows 1. Growth of U.urealyticum in 10-B media was not influenced by 0.06ng or 0.6ng per ml of estrogen by 0.1ng or 1.0ng per ml of progesterone. However, it was inhibited by high concentrations of estrogen and by progesterone. 2. Growth of U.urealyticum in MEM media was not affected by 0.06ng per ml of estrogen, but it was inhibited by high concentrations of estrogen and progesterone. 3. Growth of U.urealyticum in supernatant of FL cell culture systen was not influenced by 0.06ng per ml of estrogen, while its survival times were prolonged by high concentrations of estrogen. On the other hand, adhesion of U.urealyticum to FL cells and persistancy of the organism was increased and prolonged by high concentrations of estrogen. 4. Growth of U.urealyticum in supernatant of FL cell culture system was not increased, but its survival times were prolonged by progesterone. On the oter hand, adhered U.urealyticum to FL cells were increased and its survival times were prolonged by progesterone. Overall, we can suggest that the growth of U. urealyticum was inhibited by high concentrations of estrogen and progesterone in 10-B or MEM media. On the other hand, in FL cell culture system, the adherence of U. urealyticum to FL cells were increased and its survival times were prolonged by administration of estrogen and progesterone. We can also suggest that hormonal status is closely related with colonization of U. urealyticum in female genital tract.

가방 착용 방법에 따른 보행 시 다리관절 각도, 콥스 각, 족압 비율의 변화

이민철,이수현,장상훈,Lee, Jonathan,Lee, Su-Hyun,Jang, Sang-Hun 대한물리치료과학회 2018 대한물리치료과학회지 Vol.25 No.2

Purpose: This study was conducted to analyze the effect of bag type on gait kinematic factors. The purpose of this study was to compare the Cobb's angle, leg angle and foot pressure difference according to bag type among 20 university students. Methods: The bag type was applied with two kinds of bags: not wearing a bag, backpack, and an eco bag. The bag weight was 10% of subjects weight in during experiment and only bag weight was 0.5kg. Results: Knee joint angle is increased when wearing backpack or an eco bag than not wearing bag. Cobb's angle increased when wearing backpack and wearing eco back. The difference in right and left foot pressure increased when wearing eco bag than not wearing bag and wearing backpack. Conclusion: Therefore, wearing a heavy backpack or an eco bag when walking for a long time may cause scoliosis and change the walking form.