Weldalite 049 합금에서 탄도충격에 의해 형성된 단열성 전단밴드의 미세조직

박우진,이성학,이창길,신광선 대한금속재료학회(대한금속학회) 1996 대한금속·재료학회지 Vol.34 No.9

The microstructural development of the adiabatic shear band formed by ballistic impact studied in a Weldalite 049 alloy. The microstructure of the adiabatic shear band was examined by optical and transmission electron microscopy, revealing the existence of fine, equiaxed grains within the adiabatic shear band. This microstructure was considered to be formed in an extremely short time by the combined effects of the highly localized shear deformation and a high temperature rise occurred with the shear band. Dynamic recrystallization is suggested as a possible mechanism to explain the microstructural development of the adiabatic shear band. Although thermal effects were apparent, no evidence was found to support the melting of the alloy.

연장된 E-plane 프로브를 이용한 밀리미터파 도파관 변환기

박우진,최원석,이국주,권준범,정진호,Park, Woojin,Choe, Wonseok,Lee, Kookjoo,Kwon, Junbeom,Jeong, Jinho 한국인터넷방송통신학회 2018 한국인터넷방송통신학회 논문지 Vol.18 No.1

논문은 밀리미터파 통신 및 레이더 응용을 위한 저손실 광대역 도파관 변환기를 제안한다. 기존 E-plane 프로브 변환기는 밀리미터파 대역에서 도파관 크기를 고려하여 매우 얇고 유연한 기판을 사용한다. 하지만, 이러한 기판은 휘어지기 쉬우며 이는 성능을 크게 저하시킨다. 이러한 문제점을 해결하기 위하여 변환기 프로브가 도파관 벽면 틈에 삽입되어 고정되는 연장된 E-plane 프로브 구조를 제안하고, 두께가 $127{\mu}m$이고 유전율 2.2인 기판을 사용하여 제작하였다. W-대역 (75-110 GHz)에서 측정된 백투백(back-to-back) 변환기의 삽입 손실은 3cm 길이 도파관을 포함하여 1.35 dB (${\pm}0.35dB$)이며, 반사 손실은 13.8 dB 이상으로 아주 우수한 특성을 보였다. 따라서, 제안된 변환기는 밀리미터파 초고속 흉신 또는 고감도 레이다에 효과적으로 활용될 수 있다. In this paper, a low-loss wideband waveguide transducer is proposed for millimeter-wave communication and radar applications. A conventional E-plane probe transducer is generally designed using thin and flexible substrate at millimeter-wave frequencies, considering the very small waveguide size. However, it results in serious performance degradation caused by the bending of the substrate. In order to alleviate this problem and provide a reliable performance, we propose an extended E-plane probe transducer where the probe substrate is extended to and fix ed in the slit area formed in the waveguide wall. It is fabricated using $127{\mu}m$-thick substrate with dielectric constant of 2.2. The measurement in the back-to-hack configuration shows the excellent insertion loss of 1.35 dB (${\pm}0.35dB$) including the loss of 3 cm-long thru waveguide and return loss better than 13.8 dB over entire W-band (75-110 GHz). Therefore, it can be effectively applied for millimeter-wave high-speed communications and high-sensitivity radars.

지역난방용 중온수 열원 유기랭킨사이클 성능 특성

박우진,유호선,Park, Woo-Jin,Yoo, Hoseon 한국플랜트학회 2016 플랜트 저널 Vol.12 No.1

최근 늘어가는 에너지 수요를 화석연료에만 의존 할 수 없게 되면서 대체 에너지의 중요성이 대두되고 있으며, 이러한 상황에서 유기랭킨 사이클(Organic Rankine Cycle, 이하 ORC)등 산업체 폐열, 태양열, 지열, 해수 온도차 등의 저등급 에너지를 효과적으로 활용하기 위한 많은 연구가 진행되고 있다. 본 연구에서는 지역난방 축열시 회수수를 혼합하지 않고 ORC를 이용하여 하부사이클을 구성하여 성능해석 상용프로그램으로 작동유체 및 운전특성을 예측하였다. 지역난방수 운전조건인 열원 온도 $120^{\circ}C$, 열원 유량 $163m^3/h$(회수수 유량을 고려한 값)로 하고 이 온도에 적합한 다수의 작동유체를 선정하여 성능해석을 수행하였으며, 최고의 성능이 나타난 R245fa의 경우 269.2kW출력과 6.37%효율을 얻을 수 있었다. 또한 ORC 시스템의 응축기 압력변화에 따라 지역난방 회수수 온도가 $57.3{\sim}85^{\circ}C$범위에 형성됨으로서 보일러 입구온도상승에 따른 연료 절감 효과가 예상되었다. It is becoming increasingly important to make use of alternative energy source. because It is not able to rely on only fossil fuel for the recent increasing demand of energy consumption. With this situation, lots of studies for utilizing low grade energy such as industrial waste heat, solar energy, and geothermal energy have been conducted. The aim of this study is to predict the operation characteristics of working fluid by using performance analysis program (ThermoFlex) through the system analysis which is not mixing district return water but using ORC(Organic Rankine Cycle, hereinafter ORC) as a downstream cycle when accumulating district heating (hereinafter DH). In this study, We conducted the performance analysis for the case which has the district heating water temperature($120^{\circ}C$) and Flow rate of $163m^3/h$ (including District Heating return water flow), and examined several working fluid which is proper to this temperature. The case using R245fa (which is the best-case) showed 269.2kW power output, 6.37% efficiency. Additionally, Cut down on fuel was expected because of the boiler inlet temperature increase by being Formed $57.3{\sim}85^{\circ}C$ in a temperature of district heating return water, depending on a pressure change of a condenser in ORC system.

수치지형도를 이용한 연속지적도의 지도 일반화 기법 연구

박우진,이재은,유기윤 대한공간정보학회 2011 Spatial Information Research Vol.19 No.1

Recently, demand for the use of cadastral map is increasing in both public and private area. To use cadastral map in web or mobile environment, construction of the multi- representation database(MRDB) that is the compressed into multiple scale from the original map data is recommended. In this study, the map generalization methodology for the cadastral map by applying overlay with topographic map and polygon generalization technique is suggested. This process is composed of three steps, re-constructing the network data of topographic map, polygon merging of parcel lines according to network degree, and applying line simplification techniques. Proposed methodologies are applied to the cadastral map in Suwon area. The result map was generalized into 1:5,000, 1:20,000, 1:100,000 scale, and data compression ratio was shown in 15% 8% 1% level respectively.

철근 콘크리트 연속 유공 깊은 보의 전단내력에 관한 해석적 연구

박우진,이종권,이리형 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

The purpose of this report is investigation of shear behaviors of the deep beam through non-lineal Finite Element Method based on experimental results of continuous deep with opening. Optimum condition for analysis was selected by means of adopting various material property as variables, and additional models including different position of opening selected as variables was simulated. Also experimental result was calibrated by two formula suggested by AIJ and CIRIA, considering effect of opening in the continuous deep beams. As a result of calibration, it is possibly estimated that shear strength formula suggested by AIJ(the Architectural Institute of Japan) can be also adopted as formula for continuous beam. It is expected that results of this research which evaluated shear behavior of the continuous deep beam through non-lineal Finite Element Method can be applied data for reinforcement in the vicinity of opening in the continuous deep beams.

토지·건물정보의 융복합 및 활용을 통한 통합정보시스템 프로토타입 개발

박우진,정동훈,박정희,Park, Woo-Jin,Jeong, Dong-Hoon,Park, Jung-Hee 한국국토정보공사 공간정보연구원 2016 지적과 국토정보 Vol.46 No.2

토지정보와 건물정보는 부동산, 도시행정 분야에 있어서 가장 핵심이 되는 공간정보이지만 융복합 및 통합적인 활용이 용이하지 않아 통합정보서비스가 제공되기 어려웠다. 본 연구에서는 토지정보와 건물정보에 대한 통합정보시스템의 필요성과 정보 융합의 방법론, 통합시스템의 구축 방안을 제시하였으며 프로토타입 시스템을 개발하여 통합정보에 대한 활용 가능성을 제시하고자 하였다. 이를 위해 토지정보와 건물정보에 대한 관리 현황을 분석하였으며, 이를 바탕으로 토지 및 건물에 대한 다양한 공간정보와 속성정보 간의 매칭 및 융합 프로세스를 적용하였다. 융합된 토지 건물정보 DB를 기반으로 한 통합정보시스템과 기능을 설계함으로써 프로토타입 시스템을 구현하였다. 마지막으로, LX가 시스템을 운영하면서 부동산 및 도시행정 분야에 제공할 수 있는 정보서비스 사례들을 제시하였다. Land information and building information have highest utilization and importance in real estate and city administration area. However, providing integrated information service was difficult because conflation and integrative utilization was not easy. In this study, necessity of integrated information system, direction of integration, method of conflation and design of integrated system for land and building information are presented. In addition, the prototype system is developed and possibility of application of integrated information is proposed. For this purpose, current situation of management of land and building information was analyzed. Based on the analysis, matching and conflation processes among spatial and attribute data were applied to land and building information. Using integrated land building information DB, integrated information system and functions were designed and the prototype system was constructed. At last, information service examples in real estate and city administration area were suggested through system operation by LX.

유한요소해석에 의한 장지간 바닥판의 정적파괴형태 예측

박우진,황훈희 한국구조물진단유지관리공학회 2012 한국구조물진단유지관리공학회 논문집 Vol.16 No.4

An analytical model is presented to predict the static behavior of the long-span prestressed concrete bridge deck(the long-span PSC deck). The finite element analysis is performed and the results are compared with that of the previous experimental test. The load-deflection relationship curves by FEM are in good agreement with the results reported in the previous study. The failure mode of all test specimens is predicted by the punching shear in this study. It is also observed in the previous experimental test. The main objective of this paper is presenting supportive method to predict static behavior of the long-span PSC deck slab. It is not simulating the punching shear behavior graphically. 횡방향으로 프리스트레스가 도입된 장지간 PSC 바닥판의 정적 거동을 예측하기 위한 유한요소해석 모델을 구성하고, 해석결과를 선행연구에 의한 실험결과와 비교하였다. 유한요소해석에 의하여 서로 다른 콘크리트 강도와 프리스트레스 크기를 변수로 갖는 각각의 실험체에 대한 하중-처짐 관계 곡선을 비교적 근접하게 추정할 수 있었다. 또한, 변형률 분포와 변수에 따른 극한강도 변화로부터 펀칭전단에 의한 파괴형태와 손상범위 등을 간접적으로 예측할 수 있었다. 이 연구에서 활용된 유한요소해석 모델은 펀칭전단파괴에 의한 펀칭콘의 분리를 사실적으로 재현하기 위한 목적이 아니며, 실험연구를 위한 보조적 수단으로서 정적거동예측과 실험결과의 보완 등에 효과적으로 활용될 수 있을 것으로 판단된다.

Differentiation of Ganglioside Isomers by MALDI Tandem Mass Spectrometry with Alkali Earth Metal Additives

박우진,이동건,차상원 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.9

Gangliosides, acidic glycosphingolipids with one or more sialic acid residues, are challenging to analyze with matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) because loss of sialic acid residues is significant during ionization process, especially in the positive-ion mode. Recently, we showed that 5-methoxysalicylic acid (MSA) could be a matrix of choice for ganglioside analysis in the positive-ion mode. In this study, we investigated whether GD1a and GD1b, structural isomers with two sialic acid residues, are distinguishable by MALDI MS or tandem MS (MS/MS) with MSA and a proper salt additive. Our results showed that characteristic fragment ions of GD1a and GD1b were successfully observed by the positive-ion mode MALDI MS/MS and these diagnostic ions were more reliably detected with increased intensities when an alkali earth metal additive such as CaCl2 was employed instead of an alkali metal additive such as NaCl.

수치지형도를 이용한 연속지적도의 지도 일반화 기법 연구

박우진,이재은,유기윤,Park, Woo-Jin,Lee, Jae-Eun,Yu, Ki-Yun 한국공간정보학회 2011 한국공간정보학회지 Vol.19 No.1

최근, 지적도 이용에 대한 요구사항이 공공기관과 민간부문에서 높아지고 있는 추세이다. 지적도를 웹 환경 또는 모바일 환경에서 활용하기 위해서는 원 지도자료를 임의 단계의 축척 별로 압축해 놓은 다축척 공간표현 데이터베이스로 구축되어야 할 필요가 있다. 본 연구에서는 기존의 연속지적도를 다축척 공간표현 데이터베이스로 구축하는데 있어서 지형도와의 중첩과 폴리곤 지도 일반화 기법을 적용하는 방안에 대해서 제안하였다. 이 과정은 크게 지형도 네트워크 데이터 재구조화, 네트워크 위계에 따른 필지경계선 병합, 선형 단순화 기법 적용의 세 단계로 이루어져 있다. 본 연구에서 제안된 일반화 기법을 수원지역의 연속지적도에 적용한 결과, 1:5,000, 1:20,000, 1:100,000 세 축척의 연속지적도로 각각 일반화 되었으며, 데이터 압축률은 각각 15%, 8%, 1% 수준으로 나타났다. Recently, demand for the use of cadastral map is increasing in both public and private area. To use cadastral map in web or mobile environment, construction of the multi-representation database(MRDB) that is the compressed into multiple scale from the original map data is recommended. In this study, the map generalization methodology for the cadastral map by applying overlay with topographic map and polygon generalization technique is suggested. This process is composed of three steps, re-constructing the network data of topographic map, polygon merging of parcel lines according to network degree, and applying line simplification techniques. Proposed methodologies are applied to the cadastral map in Suwon area. The result map was generalized into 1:5,000, 1:20,000, 1:100,000 scale, and data compression ratio was shown in 15% 8% 1% level respectively.

10 mm 이상의 상부요관결석 치료에서 후복막강경요관절석술의 역할: LithoclastⓇ를 이용한 경성요관경하배석술과의 비교

박우진,권준오,오태희 대한비뇨의학회 2009 Investigative and Clinical Urology Vol.50 No.4

Purpose: We evaluated the outcome of laparoscopic retroperitoneal ureterolithotomy (LRU) and compared the results with the rigid ureteroscopic removal of stones with the LithoclastⓇ (rigid URS) for the management of large upper ureteral stones (≥10 mm). Materials and Methods: Between July 2002 and March 2008, rigid URS and LRU were performed in 37 and 24 patients, respectively. We evaluated the outcomes of each procedure and compared the success rate according to the location (above and below the L3 level by the third intervertebral disc of the lumbar spine) and size of the stones (10-15 mm and ≥15 mm in diameter). Results: The overall success rate for rigid URS and LRU were 70.3% (26/37) and 91.7% (22/24), respectively (p=0.059). For rigid URS, the success rate was 50.0% (8/16) and 85.7% (18/21) for stones above and below the L3 level (p=0.030), respectively, and 85.7% (23/28) and 33.3% (3/9) for stones 10-15 mm and ≥15 mm in diameter, respectively (p=0.011). For LRU, the success rate was 92.3% (12/13) and 90.9% (10/11) for stones above and below the L3 level, respectively (p=0.902), and 50.0% (1/2) and 95.5% (21/22) for stones 10-15 mm and ≥15 mm in diameter, respectively. Conclusions: LRU demonstrated a high success rate regardless of the location and size of the stones. The outcomes with rigid URS were more varied. These results suggest that LRU is a feasible alternative for large upper ureteral stones that are 15 mm or more in size or located above the intervertebral disc between the third and fourth lumbar vertebrae. Purpose: We evaluated the outcome of laparoscopic retroperitoneal ureterolithotomy (LRU) and compared the results with the rigid ureteroscopic removal of stones with the LithoclastⓇ (rigid URS) for the management of large upper ureteral stones (≥10 mm). Materials and Methods: Between July 2002 and March 2008, rigid URS and LRU were performed in 37 and 24 patients, respectively. We evaluated the outcomes of each procedure and compared the success rate according to the location (above and below the L3 level by the third intervertebral disc of the lumbar spine) and size of the stones (10-15 mm and ≥15 mm in diameter). Results: The overall success rate for rigid URS and LRU were 70.3% (26/37) and 91.7% (22/24), respectively (p=0.059). For rigid URS, the success rate was 50.0% (8/16) and 85.7% (18/21) for stones above and below the L3 level (p=0.030), respectively, and 85.7% (23/28) and 33.3% (3/9) for stones 10-15 mm and ≥15 mm in diameter, respectively (p=0.011). For LRU, the success rate was 92.3% (12/13) and 90.9% (10/11) for stones above and below the L3 level, respectively (p=0.902), and 50.0% (1/2) and 95.5% (21/22) for stones 10-15 mm and ≥15 mm in diameter, respectively. Conclusions: LRU demonstrated a high success rate regardless of the location and size of the stones. The outcomes with rigid URS were more varied. These results suggest that LRU is a feasible alternative for large upper ureteral stones that are 15 mm or more in size or located above the intervertebral disc between the third and fourth lumbar vertebrae.