Sn-1.7Bi-0.7Cu-0.6In 솔더의 특성 연구

박지호,이희열,전지헌,전주선,정재필,Park, Ji-Ho,Lee, Hee-Yul,Jhun, Ji-Heon,Cheon, Chu-Seon,Jung, Jae-Pil 대한용접접합학회 2008 대한용접·접합학회지 Vol.26 No.5

Characteristics of Sn-1.7%Bi-0.7%Cu-0.6%In (hereafter, SBIC) lead-free solder was investigated in this study. The results from SBIC were compared to other lead-free solders such as Sn-3.5%Ag-0.7%Cu (hereafter, SAC), Sn-0.7%Cu (hereafter, SC), and lead-bearing Sn-37%Pb (hereafter, SP) alloy. Tensile properties of bulk solder, wettability, spreading index, bridge and dross were evaluated. As experimental results, tensile strength and elongation of SBIC was 62.5MPa and 21.5%, respectively. The tensile strength was comparable to that of SP solder. The wetting time of SBIC was 1.2 sec at $250^{\circ}C$, and its wetting properties including wetting force were as good as the SAC alloy. However, wettability of the SC was not so good as the SBIC and SAC. The spreading index of SBIC at $250^{\circ}C$ was 71 %, and it was similar level to those of SAC and SC solders. Bridging was not found for all solders of SBIC, SAC and SC in the range from 240 to $260^{\circ}C$. In dross test at $250^{\circ}C$ for an hour, the amount of dross produced from SBIC was about 57% compared to that from SAC.

거대세포바이러스 조기항원 단백질에 대한 단세포군 항체 제조에 관한 연구

박지호,손영모,박규현,이원영,Park, Ji Ho,Sohn, Young Mo,Park, Kyu Hyun,Lee, Won Young 대한소아감염학회 1999 Pediatric Infection and Vaccine Vol.6 No.2

목 적 : human CMV가 생성하는 분자량 72,000 dalton의 immediate early protein(p72)과 반응하는 단세포군 항체를 국내에서 분리된 CMV 야생주로 직접 제작하여 진단에 사용해 보기 위한 것이다. 방 법 : 정상 인체 섬유아세포(Foreskin 유래)를 10% 우태아혈청이 함유된 Eagle' s minimal essential medium(MEM)에서 배양하여 사용하였으며 마우스 골수종세포는 P3X63 Ag8.653(ATCC, Mary land USA)을 $5{\times}10^5/ml$ 세포수를 유지하도록 배양하였다. 사용된 항원은 선천성 CMV 감염아의 소변으로부터 검출한 CMV(KJHJ90)를 대량 증식시켜 사용하였다. 생후 6~8주된 Balb/c마우스의 복강내에 CMV 항원을 1주일 간격으로 4회 주사한 후 면역시킨 마우스 비장에서 얻은 임파구와 형질세포종세포로 최적발육기의 P3X63-Ag8.653을 사용하여 융합하였다. 융합세포를 배양한 후 간접면역형광항체법을 이용하여 항체가가 높은 것을 골랐다. 결 과 : 생산된 28종의 단세포군항체 중 그림 1과 같이 LPC12와 LPC23클론이 AD169에 감염된 세포의 핵에 특히 강하게 반응하였다. 정제된 AD169를 SDS-PAGE한 후 Western blotting을 하여 생산된 단세포군항체가 반응하는 항원의 분자량을 확인하였으며 그 중 LPC12와 LPC23클론에서 생성된 단세포군항체는 약 72KDA의 항원과 특이적으로 가장 강하게 반응하였다. 결 론 : 본 연구에서 제작된 LPC12와 LPC23 클론에서 생성된 단세포군 항체를 이용하여 선천성 CMV감염으로 확인된 소아의 소변을 이용하여 CMV AD 169 주 유래 항체(P63-27)과 비교한 DEAFF 검사상 동일한 결과를 확인한 바 LPC12와 LPC 23 클론 항체는 AD 169(P63-27)과 같이 CMV 감염의 조기진단에 사용할 수 있을 것으로 사료된다. Purpose : The purpose of this study is to make and use monoclonal Ab which reacts with CMV major immediate early(${\alpha}$) protein(p72). Methods : Normal human fibroblast(Foreskin derived) was cultured in Eagle's minimal essential medium(MEM) containing 10% cowfetus serum and mouse chondroblast was cultured in P3X63 Ag8.653(ATCC. Maryland USA) to maintain $5{\times}10^5/ml$ cell counts. CMV(KJHJ90) from congenital CMV infected infant's urine was multiplied and used for Ab making. CMV Ag was injected 4 times, 1 week interval into the peritoneal space of 6~8 weeks old mice. And then lymphocyles and fibroblasts taken from spleen were obtained and conjugated. After the conjugated cell cultured, we chose the cell that had high Ab titer using indirect immunofluerescent method. Results : Among the 28 monoclonal antibodies obtained LPC12 and LPC23 reacted highly with nucleus of AD169 infected cell. Purified AD169 after SDS-PAGE, molecular weight of Ag, which reacted with purified monoclonal Ab, was obtained using Western blotting. Monoclonal Ab of LPC12 and LPC23 clone reacted most highly with 72 kd Ag. Conclusion : LPC12 and LPC23 clonal Ab with AD 169(P63-27) is useful on early diagnosis of CMV infection.

Special Report - 스마트TV 서비스 전망

박지호,Park, Ji-Ho 한국정보통신기술협회 2011 TTA저널 Vol.135 No.-

Cell Model 에 기반한 새로운 상태방정식에 관한 연구

박지호,홍무호,김화용 ( Ji Ho Park,Moo Ho Hong,Hwa Yong Kim ) 한국화학공학회 1996 화학공학의이론과응용 Vol.2 No.2

FlexRay 네트워크 시스템을 위한 FIBEX 자동 생성 알고리즘에 관한 연구

박지호,이석,이경창,Park, Ji-Ho,Lee, Suk,Lee, Kyung-Chang 대한임베디드공학회 2013 대한임베디드공학회논문지 Vol.8 No.2

As vehicles become more intelligent for safety and convenience of drivers, in-vehicle networking systems such as controller are network (CAN) have been widely used due to increasing number of electronic control unit (ECU). Recently, FlexRay was developed to replace CAN protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. However, it is difficult for vehicle network designers to calculate platform configuration registers (PCR) and determine a base cycle or slot length of FlexRay. To assist vehicle network designers for designing FlexRay cluster, this paper presents automatic field bus exchange format (FIBEX) generation algorithm from CANdb information, which is de-facto standard database format for CAN. To design this program, structures of FIBEX, CANdb and relationship among PCR variables are analyzed.

정상상태 전압제어를 위한 UPFC와 조상설비의 협조

박지호(Ji-Ho Park),이상덕(Sang-Duk Lee),정태영(Tae-Young Jyung),정기석(Ki-Seok Jeong),백영식(Young-Sik Baek),서규석(Gyu-Seok Seo) 대한전기학회 2011 전기학회논문지 Vol.60 No.5

This paper presents a new method of local voltage control to achieve coordinative control among UPFC(Unified Power Flow Controller) and conventional reactive compensation equipments , such as switched-shunt and ULTC(Under-Load Tap Changing) transformer. Reactive power control has various difficult aspects to control because of difficulty of system analysis. Recently, the progress of power electronics technologies has lead to commercial availability of several FACTS(Flexible AC Transmission System) devices. The UPFC(Unified Power Flow Controller) simultaneously allows the independent control of active and reactive power flows as well as control of the voltage profile. When conventional reactive power sources and UPFC are used to control system voltage , the UPFC reacts to the voltage deviation faster than the conventional reactive power sources. Keeping reactive power reserve in an UPFC during steady-state operation is always needed to provide reactive power requirements during emergencies. Therefore, coordination control among UPFC and conventional reactive power sources is needed. This paper describe the method to keep or control the voltage of power system of local area and to manege reactive power reserve using PSS/E with Python. The result of simulation shows that the proposed method can control the local bus voltage within the given voltage limit and manege reactive power reserve.

제철소 소내 전력계통의 부하차단 방안

박지호(Ji-Ho Park),서규석(Gyu-Seok Seo),정기석(Ki-Seok Jeong),이현철(Hyun-cheol Lee),백영식(Young-Sik Baek) 대한전기학회 2013 대한전기학회 학술대회 논문집 Vol.2013 No.7

연구발표 초록 ( 열역학 (Ⅱ) ) : 연속열역학을 이용한 Kentucky No . 9 Coal Liquid 의 해석

박지호 (학),김화용 (정) ( Ji Ho Park,Hwa Yong Kim ) 한국화학공학회 1991 추계학술발표회 Vol.- No.-

풍력 블레이드의 결빙에 의한 공력특성 및 성능 변화

박지호(Ji-Ho Park),명노신(Rho-Shin Myong) 한국항공우주학회 2014 韓國航空宇宙學會誌 Vol.42 No.2

추운 기후에서 운영되는 풍력터빈 시스템의 표면에 발생한 결빙으로 인하여 공기역학적 성능이 크게 저하될 수 있다. 이러한 결빙은 양력감소 및 항력증가를 야기하고, 발전효율에 부정적인 영향을 미치게 된다. 이로 인하여 풍력발전기의 성능저하 또는 과부하, 무게중심의 변화에 따른 과도진동, 결빙파편이 지상으로 떨어질 경우의 안전성 문제, 계기의 결빙으로 인한 계기 측정오차, 최악의 경우 풍력 시스템 정지 등의 문제가 발생한다. 본 연구에서는 결빙증식이 풍력 발전기의 공력특성에 미치는 영향을 CFD 기법을 이용해 분석하였다. 또한 결빙증식 결과를 바탕으로 BEM 기법을 적용시켜 삼차원 블레이드에 대한 공력성능을 계산하였다. 결빙의 두께는 상대적인 속도차이에 의해 블레이드 중심에서 끝단으로 갈수록 증가함을 알 수 있었고, 공기의 속도가 결빙증식에 미치는 주요 인자임을 확인하였다. A significant degradation in the aerodynamic performance of wind turbine system can occur by ice accretion on the surface of blades operated in cold climate. The ice accretion can result in performance loss, overloading due to delayed stall, excessive vibration associated with mass imbalance, ice shedding, instrumental measurement errors, and, in worst case, wind turbine system shutdown. In this study, the effects of ice accretions on the aerodynamic characteristics of wind turbine blade sections are investigated on the basis of modern CFD method. In addition, the computational results are used to predict the performance of three-dimensional wind turbine blade system through the blade element momentum method. It is shown that the thickness of ice accretion increases from the root to the tip and the effects of icing conditions such as relative wind velocity play significant role in the shape of ice accretion.

Robust Internal Model Control of Three-Phase Active Power Filter for Stable Operation in Electric Power Equipment

Ji-Ho Park(박지호),Dong-Wan Kim(김동완) 대한전기학회 2013 전기학회논문지 Vol.62 No.10

A new simple control method for active power filter, which can realize the complete compensation of harmonics is proposed. In the proposed scheme, a model-based digital current control strategy is presented. The proposed control system is designed and implemented in a form referred to as internal model control structure. This method provides a convenient way for parameterizing the controller in term of the nominal system model, including time-delays. As a result, the resulting controller parameters are directly set based on the power circuit parameters, which make tuning of the controllers straightforward task. In the proposed control algorithm, overshoots and oscillations due to the computation time delay is prevented by explicit incorporating of the delay in the controller transfer function. In addition, a new compensating current reference generator employing resonance model implemented by a DSP(Digital Signal Processor) is introduced. Resonance model has an infinite gain at resonant frequency, and it exhibits a band-pass filter. Consequently, the difference between the instantaneous load current and the output of this model is the current reference signal for the harmonic compensation.