2 kW급 브레이튼 냉동기용 열역학 사이클 및 극저온 터보 팽창기 설계

이진우,이창형,양형석,김석호,Lee, Jinwoo,Lee, Changhyeong,Yang, Hyeongseok,Kim, Seokho 한국전력공사 2016 KEPCO Journal on electric power and energy Vol.2 No.2

초전도 전력 케이블의 상용화 노력에 따라 점차 장선화 되면서, 단위 냉각 시스템당 냉각용량이 큰 대용량 냉동기의 필요성이 증가하고 있다. 국내에서는 극저온 냉동기에 대한 기술 부족으로 인해 현재 극저온 냉동기는 해외 선진사로부터 고가의 비용으로 수입되고 있다. 초전도 전력 케이블의 상용화를 위해서는 대용량 브레이튼 냉동기의 국내 개발이 시급하다. 대용량 브레이튼 냉동기의 구성은 복열식 열교환기, 압축기, 극저온 터보 팽창기로 구성되어 있으며, 냉동기 효율과 가장 직접적인 연관이 있는 것은 극저온 터보 팽창기이다. 극저온 터보 팽창기는 극저온에서 고속으로 회전하면서 고압의 헬륨 혹은 네온 가스를 팽창시켜 온도를 낮추는 역할을 한다. 본 논문에서는 역브레이튼 냉동 사이클을 설계하고, 이에 적합한 극저온 터보 팽창기를 설계하였다. The High Temperature Superconducting power cables (HTS power cables) become increasingly longer to commercialize the HTS power cable system. Accordingly, demands on refrigerators of large cooling capacity per a unit system have been increased. In Korea, it is currently imported from abroad with the high price due to insufficient domestic technologies. In order to commercialize the HTS power cables, it is necessary to develop the refrigerators with large cooling capacity. The Brayton refrigerators are composed of recuperative heat exchangers, compressors and cryogenic turbo expanders. The most directly considering the efficiency of the Brayton refrigerator, it depends on performance of the cryogenic turbo expander. Rotating at high speed in cryogenic temperature, the cryogenic turbo expanders lower temperature by expanding high pressure of a helium or neon gas. In this paper, the reverse Brayton cycle is designed and the cryogenic turbo expander is designed in accordance with the thermodynamic cycle.

지역거점 공공병원의 환경적 요인에 따른 생산성 분석

이진우,Lee, Jinwoo 한국병원경영학회 2017 병원경영학회지 Vol.22 No.3

The purpose of this study is to analyze the difference of productivity according to environmental factors among 25 Regional base public hospitals. Also this study is to propose a method to improve the productivity of Regional base public hospitals in the future by improving the public performance and stable management performance by studying the productivity variables affecting profitability. The survey period was based on the last three years, and 25 Regional base public hospitals were selected for the survey. The dependent variable is the total capital medical marginal profitability and the medical profit marginal profitability which are the indicators of profitability. The independent variable, productivity, is classified into three indicators: capital productivity, labor productivity, and value added productivity. The ANOVA analysis method was used to analyze the productivity difference according to the frequency factor and the environmental factors of the Regional base public hospitals. Finally, we conducted a hierarchical regression analysis to examine the productivity variables affecting profitability. The results of this study showed that there were differences in productivity due to environmental factors such as hospital size, competition in the local medical market, and differences in management performance. The difference in productivity and profitability depending on the environmental factors suggests that it is difficult for Regional base public hospitals in each regional base to perform a balanced public service. In order to overcome this, it is necessary to provide balanced medical services such as government financial support expansion, regional medical demand forecasting and facility infrastructure construction.

무인 지상 차량 네트워크에서 GPS 재밍에 강인한 위치기반 라우팅

이진우,정우성,김용주,고영배,함재현,최증원,Lee, Jinwoo,Jung, Woo-Sung,Kim, Yong-joo,Ko, Young-Bae,Ham, Jae-Hyun,Choi, Jeung-Won 한국군사과학기술학회 2015 한국군사과학기술학회지 Vol.18 No.4

UGVs(Unmanned Ground Vehicles) are robots that can substitute humans in reconnaissance operations of potentially dangerous and contaminated sites. Currently, there have been active research on utilizing UGVs in military environments. Much resrach has been focused on exploiting the weakness of topology-based routing and instead utilize location-based routing for the networking of UGVs. It is generally assumed that location-based routing methods can fully utilize the location information gained from GPS. However, this may not be possible in tactical environments due to enemy GPS jamming and LOS(Line of Sight) limitations. To solve this problem, we propose a location-based routing scheme utilizing low control message that can calibrate the location information using GPS information as well as location of neighboring UGV, movement direct and speed information. Also utilizing topology-based routing scheme to solve incorrect location information in GPS jamming region.

[특집4] 자동차용 고강도강판 소재 기술개발 및 성형기술 동향

이진우(Jinwoo Lee),이명규(Myoung-Gyu Lee) 한국자동차공학회 2014 오토저널 Vol.36 No.3

Finite element modeling of plastic deformation of AZ31B Mg alloy under a pulse electric current

Jinwoo Lee(이진우),Yong-Chan Her(허용찬),Daeyong Kim(김대용),Se Jong Kim(김세종),Young-Seon Lee(이영선) 한국자동차공학회 2015 한국자동차공학회 부문종합 학술대회 Vol.2015 No.5

연료분무 및 연소 1 : 연료 온도가 디젤 인젝터의 유량 및 분무 발달 과정에 미치는 영향에 관한 연구

이진우 ( Jinwoo Lee ),표순찬 ( Soonchan Pyo ),배충식 ( Choongsik Bae ) 한국액체미립화학회 2015 한국액체미립화학회 학술강연회 논문집 Vol.2015 No.-

The characteristics of fuel quantity, injection rate and macro spray pattern including flame development was investigated under various diesel fuel temperature. Real injection quantity showed decreasing tendency despite of the same signal of start of injection and injection duration as the fuel temperature decreased. Injection rate measurement verified that the real start of injection was delayed and the real injection duration was shortened with lower fuel temperature condition, which explains the reason why injection quantity decreased. Spray tip penetration with lower fuel temperature was longer than that with higher fuel temperature due to deteriorated atomization. From the combustion visualization, it was revealed that irregular flame pattern from each injector hole was shown with low flame intensity with low fuel temperature condition. To overcome combustion process under cold temperature condition, multiple injection strategy was applied with single and double pilot injections. Overall heat release rate was increased with multiple injection strategy with higher luminosity intensity. However, more careful application with multiple injections is need under cold ambient condition due to the concern of high HC emission. More results related with fuel temperature will be presented further during the conference.

차기 TMMR을 위한 개선된 무선랜 QoS 기법

이진우(Jinwoo Lee),이홍로(Hongro Lee),고영배(Young-Bae Ko) 한국통신학회 2014 한국통신학회 학술대회논문집 Vol.2014 No.1

Artificial Neural Network Based Failure Diagnosis of Temperature Sensor Embedded in Hot Plate

Jinwoo Lee(이진우),Daeil Kwon(권대일),Yoonki Sa(사윤기) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

임금지급의무에 붙은 부관의 유효요건 - 서울고등법원 2019. 11. 12. 선고 2018나2071008 판결 -

이진우(Lee, Jinwoo) 한국법학원 2020 저스티스 Vol.- No.181

대상판결은 사용자의 임금(기본급 중 일부)지급의무에 붙은 정지조건에 대하여, 헌법 제32조 제3항 및 근로기준법 제43조 제1항, 제2항이 임금에 관하여 일체의 조건을 부가하는 것을 금지하는 취지라고 할 수 없고, 해당 조건을 정당화할 수 있는 합리적인 이유가 있고 근로자가 자유로운 의사 하에 해당 조건을 승낙하였다면 그 조건은 유효하다고 판시함으로써 그 유효요건을 제시하였다. 임금채권은 법령상 특별한 보호가 주어지고 그 보호에는 일정한 범위가 존재하므로, 임금지급의무에 붙인 부관의 유효요건도 그에 연동하여 적절한 범위에서 설정되어야 할 필연성이 있다. 임금에 붙은 부관의 일반적인 유효요건은 임금항목의 성질(기본급성, 특정목적 지향성의 정도)에 상응하여, 구체적인 근로제공의 실태 및 근로자가 조건의 충족 여부를 컨트롤하거나 예상할 수 있는지까지 감안하여 해당 부관 내용의 합리성을 음미하고, 부관의 부가에 대한 근로자의 동의 수준을 차등적으로 설정 · 요구하여 종합판단 방식으로 운용함이 바람직하다. 대상판결은 (i) 기본급에 대하여 (ii) 정지조건을 붙였으며 (iii) 근로자가 조건의 성취 여부를 컨트롤할 수 없고 예상하기도 어려우며 (iv) 금액비중이 70%에 달하고 (v) 기본적인 생활자금이라는 기본급의 지급목적과 강북구로부터 보조금을 지급받는다는 조건의 내용 사이에 상관성은 없지만, 강북문화원의 재무구조상 강북구로부터 보조금을 받지 않으면 월 250만 원을 지급할 재원이 없고 근로자도 그러한 사정을 잘 알고 있었으며, 구체적인 근로제공의 실태를 보면 근로자는 건설업을 겸업하기도 하였고 스스로 자원봉사 개념이라고 인식하고 있었던 것으로 보아 지휘 · 감독이나 종속성의 정도가 약했던 것으로 보이는 사안에 대한 것이다. 종합적으로 보았을 때, 당해 정지조건의 유효요건으로서는 가장 강력한 (i) 조건의 부가를 정당화할 수 있는 합리적인 이유와 (ii) 개별 근로자의 자유의사에 기한 명확한 동의를 요구함이 타당하다. The Seoul High Court decision which is about the condition precedent attached to the employer’s obligation to pay wages held that it cannot be said that Article 32(3) of the Constitution and Article 43(1) and (2) of the Labor Standards Act prohibit the addition of any conditions regarding wages, and that the condition is valid, if there is a reasonable reason to justify the condition and the worker has freely agreed to the condition. Since the right to claim wages is given special protection in accordance with laws and regulations and there is a certain range of protection, it is inevitable that the valid requirements of the additional clauses attached to the wage payment obligations should be set to the appropriate extent in conjunction with it. The general validity requirements of the additional clauses attached to wages should correspond to the nature of the wage category (basic salary, orientation for specific purposes), taking into account the concrete factual circumstances of labor and whether the worker can control or predict if the conditions will be met. It is desirable to weigh all the elements comprehensively, while examining the rationality of the contents of the additional clauses and differentiating the level of consent of the worker for the addition of the clauses. The factual backgrounds of the decision were (i) a condition precedent was attached to (ii) the basic salary, (iii) the worker could not control nor predict whether the condition was fulfilled, (iv) the amount subject to the condition reached 70% of the wage, and (v) while there is no correlation between the purpose of basic wages, which is a basic living fund, and the condition of receiving subsidies from Gangbuk-gu, but due to the financial structure of the Gangbuk Cultural Center, there is no financial resource to pay 2.5 million won per month unless subsidies are received from Gangbuk-gu, and the worker was well aware of such circumstances. Also, considering the actual circumstances of labor, it seems that the level of command and supervision was relatively weak, as the worker was running his own construction business and perceived his job at the Gangbuk Cultural Center as a volunteer concept. Taken together, it is reasonable to apply the most rigid effectiveness requirements, which are (i) reasonable reasons to justify the addition of the condition and (ii) a clear consent of the individual worker based on the free will to the condition.

군 전술 네트워크를 위한 항재밍 ODMRP 기법

이진우(Jinwoo Lee),신대욱(Daewook Shin),고영배(Young-Bae Ko) 한국통신학회 2013 한국통신학회 학술대회논문집 Vol.2013 No.11