ERROR ESTIMATES FOR THE FULLY DISCRETE STABILIZED GAUGE-UZAWA METHOD -PART I: THE NAVIER-STOKES EQUATIONS

Pyo, Jae-Hong The Kangwon-Kyungki Mathematical Society 2013 한국수학논문집 Vol.21 No.2

The stabilized Gauge-Uzawa method (SGUM), which is a second order projection type algorithm to solve the time-dependent Navier-Stokes equations, has been newly constructed in 2013 Pyo's paper. The accuracy of SGUM has been proved only for time discrete scheme in the same paper, but it is crucial to study for fully discrete scheme, because the numerical errors depend on discretizations for both space and time, and because discrete spaces between velocity and pressure can not be chosen arbitrary. In this paper, we find out properties of the fully discrete SGUM and estimate its errors and stability to solve the evolution Navier-Stokes equations. The main difficulty in this estimation arises from losing some cancellation laws due to failing divergence free condition of the discrete velocity function. This result will be extended to Boussinesq equations in the continuous research (part II) and is essential in the study of part II.

비정질 인듐갈룸ᅳ아연-산화물 박막트랜지스터 기반의 AMOLED 화소 회로

이재표(Jae-Pyo Lee),유경민(Kyeong-Min Yu),장진녕(JinNyoung Jang),홍문표(MunPyo Hong),배병성(Byung Seong Bae) 호서대학교 공업기술연구소 2013 공업기술연구 논문집 Vol.32 No.2

본 논문은 비정질 인둠ᅳ갈f ᅳ아연-산화물 박막트랜지스터 (a-IGZO TFT)를 이용하여 능동형 유기발광다이오드 (AMOLED)용 문턱전압(Vth )을 보상하는 화소 회로를 제안하였다. 산화물 TFT는 n-채널 TFT로써, 우리는 n-채널 TFT 특성으로 회로를 최적화하였다. 제안된 화소 회로는 회로 시뮬레이션 뿐만 아니라 회로 분석을 이용하여 확인되었다. 제안된 화소 회로는 AMOLED에서 구동 TFT의 문턱전압 변화를 보상할 수 있다. 제안된 화소 회로를 이용함으로써, 문턱전압 보상은 달성되었다. rhis paper proposes a tnresnold voltage compensation pixel circuit for active-matrix organic light-emitting diode (AM OLED) using amorphous indium-gaUiimi-zinc-oxide thin-film transistors (a-IGZO TFTs), Oxide TFT is an n-channel TFT; therefore, we optimized the circuit for the n-channel TFT characteristics. The proposed pixel circuit was verified using circuit analysis as well as circuit simulations. The proposed circuit could compensate for the threshold voltage variations o f drive TFT in AM OLED. Using the proposed pixel circuit, threshold voltage compensation was achieved.

L.A. Olympic 男子 Hand ball 競技에 關한 考察

洪盛杓,柳在忠 忠南大學校體育科學硏究所 1984 體育科學硏究誌 Vol.2 No.1

The purpose of this study is provide fundamental information selection of handball player and training program for improvement of korean male handball players' athletic performance in Seoul Asian Game and Seoul Olympic Game which will be held in 1986 and 1988. For this study, all male handball game in LA. Olympic Game which was held in U.S.A. during 1984. 7.31-1984. 8.11 was surveyed.. Following conclusions were abtained : 1. To raise the National Handball Players average age over 3 years, business team have to be organized, and then the National Team have not to be composed only players of college. 2. Standing Height, and Body Weight of players would have to be increased over 190 ㎝ in height, 90kg in weight, and 46% in body weight ratio. 3. To gain a good rank, the ratio of gained and losed point have to be closely 6:4. And the game contents which was made of 60 % of attack, 20% of fast break, and 20% of penalty throw is desirable. 4. Defence tactics which can reduce the ratio of losed point by attack and offence tactics by fast break have to be developed. 5. Positive and Active play for Ten minutes after beginning is very need because of the remarkable difference of ratio of gained and losed point after beginning first or second half.

마이크로스트립 어레이 안테나에 관한 연구

洪在杓 慶一大學校 1993 論文集 Vol.9 No.1

In recent effforts to improve radiation characteristics and wider bandwidth of the antenna, extensive researches are being reported on directly coupled rectangular microstrip patch antenna by microstrip line and gap coupled rectangular microstrip antenna. The increasing use of the microstrip array antenna technology requries H-plane analysis methods capable of calculating the return loss, radiation pattern, the resonant frequency, and the equivalent circuit of the antenna, etc. In this paper, H-plane microstrip array antenna directly coupled to nonradiating edges is presented and analyzed for broadening bandwidth. The radiation admittance derived from the slitted parallel-plate wave-guide filled with a homogeneous dielectric and the conventional transmission line model are used in representing the equivalent circuit of the array antenna. The dimensions of the array antenna configuration with a broader bandwidth are determined from computer simulation by changing several parameters : patch length, feed point. For the array antenna which contains the optimum values of these parameters, the return loss and bandwidth are theoretically computed.

빔 구조물의 손상평가를 위한 임피던스 기술의 응용

홍동표,홍용,왕고평,김병진,김영문,이재정,김재열 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

This paper presents a primary study for a new method of enhancing measurement using impedance analysis method, which is widely used for structure health monitoring. Many of skyscrapers, bridges, tunnels, which have been built up several years, and nearly reached their operating life due to aging crack, material deterioration, and so on. therefore, the health monitoring technique has obtained considerable attention. The goal of this research is to show basic information to evaluate structural health condition using piezoelectric sensors. The piezoelectric materials have various merits. It is easy to shape various forms and can be embedded on the materials more conveniently. Moreover, the excitation frequency can be changed and the piezoelectric sensors cost less. All these features make the piezoelectric-based system applicable to structural healthy monitoring. This work presents a study for the development of a practical and quantitative technique for assessment of the structural health condition by piezoelectric impedance-based technique associated with longitudinal wave propagation. To estimate the damage condition numerically, we suggest the evaluation method Cov (Covariance) and CC (Correlation Coefficient) in this paper.

중증 만성정신질환자 수의 추산 : Through Two Community Surveys 두 지역사회 조사를 중심으로

홍진표,김윤,배재남,정유진,강영호,양병국,김용익,김병후,이철,조맹제 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.2

국내 중증 만성정신질환자 수를 추정하기 위하여 일 농촌 및 대도시 지역의 지역의료보험 및 의료보호 대상자 중 1993년 1년간 의료기관에서 정신증 상병(ICD-9 code 상 290-299) 및 알콜 남용/중독, 성격장애 및 정신박약 진단하에 치료를 받은 적이 있는 사람에 대해 설문조사를 실시하였다. 연구자들이 개발한 진단도구를 이용하여 진단을 평가하고, Strauss-Carpenter scale 등을 이용하여 기능 장애를 평가하고 유병기간 등을 조사하였다. 결과를 요약하면 다음과 같다. 1) 진단평가상 정신분열병군(61.1%)이 가장 많았으며, 정동장애군(23.7%), 알콜장애군(11.2%), 기질성 정신장애군(4.0%)의 순서이었다. 2) 직업활동정도는 진단군별로 차이가 많았다. 지난 1년간 직업활동이 6개월 미만이거나 전혀 없는 환자 비율이 정신분열병군은 67.2%, 알콜장애군 52.0%, 정동장애20.8%의 순으로 정신분열병군이 가장 불량하였다. 3) 사회활동도 진단군별로 차이가 많아서 지난 1년간 의도적, 사회활동이 없는 비율이 정신분열병군이 가장 높았고(72.3%), 알콜장애군(32.0%), 정동장애군(20.7%)의 순이었다. 4) 국내 의료보험 및 사회복지시설 이용 자료 등을 토대로 본 조사 결과를 적용한 결과 국내중증 만성 정신질환자의 수는 약 8만 7천명으로 추산되었다. Objectives: The purpose of this study was to estimate the number of serious and persistent mentally ill patients in Korea. Methods : Study populations were recruited from medical insurance data of two district areas ; one rural and the other urban areas. Subject were all mentally ill who had ever visited any hospital in 1993 and were diagnosed as having psychosis, personality disorder and drug abuse. We conducted a home visiting survey applying semi-structured diagnostic interview, assessing the level of social adjustment with Strauss-Carpenter Scale, and past psychiatric history by the trained researchers, in October and November,1994. Results : According to diagnostic assessment schizophrenic patients constituted the major portion(61.1%) of study subjects. The distribution of occupational functions and social contacts was variable according to diagnosis. Most schizophrenic patients were unemployed or worked less than 6 months in the previous year(67.2%), and showed poor social contact(72.3%). But affective disorder patients were relatively independent in job maintenance and social relationship. Alcoholic patients lay between those of schizophrenic and affective disorder groups. It was estimated that about 87,000 adult Koreans were suffering from chronic mental disorders which seriously interfere with their daily life. Conclusions : Serious and persistent mentally ill patients were common in Korea. Community support program should be provided for them.

자가 Fibrin Glue와 연골세포를 이용한 연골조직 공학 기법에 관한 연구

홍성표,범진식,박재경,김진영,이두형 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.3

Neomorphogenesis of cartilage using chondrocyte-polymer constructs is a potential source for development of cartilage reconstruction. Current tissue engineering techniques of neocartilage rely on in vivo implantation of polymer-chondrocyte constructs. The purpose of this study was to find a way to bioengineer cartilage in vitro by entrapping chondrocytes in a molded autologous fibrin glue. Chondrocytes isolated from the cartilage of rabbit joints were combined with fibrinogen extracted by a single cryoprecipitation of autologous plasma, and they were then polymerized with thrombin to create a fibrin glue with a final cell density of 2.5x10?? cells/ml. The collagen for a control study was used as a polymer. The polymer-chondrocyte constructs were cultured for 4 weeks and the fibrin-chondrocyte constructs molded in the shape of a human ear were cultured for 6 weeks in vitro. Morphometric, histochemical, and histomorphometric analysis including glycosaminoglycan quantitation confirmed the following results: 1) Highly-concentrated autologous fibrinogen was easily extracted by a single cryoprecipition of autologous olasma. 2) The fibrin-chondrocyte constructs demonstrated the presence of actively proliferating chondrocytes with the production of cartilaginous matrix(collagen and glycosaminoglycan) at 1 week after culture, as well as gross and histologic evidence similar to those of normal cartilage at 3∼4 weeks after culture. 3) The collagen-chondrocyte constructs demonstrated lower degrees of hardness and transparency, as well as a lower density of cells and glycosaminoglycan during the culture period. 4) Neocartilage generated from fibrin-chondrocyte constructs in the shape of a human ear nearly retained their original configuration and size without degeneration for 6 weeks of culture in vitro. This study demonstrated a novel method for bioengineering the molded cartilage in vitro using autologous fibrin glue as a matrix scaffold. The generated cartilage showed gross and histologic evidence similar to those of normal cartilage, retaining the original gross dimension. With further refinement, this may be a new application of tissue engineering for the reconstruction of cartilage.

데스크탑 마이크로 성형시스템의 가진성형에 따른 동특성 연구

홍동표,고유곤,홍용,김현식,이재완 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

In this study, a desktop forming system which enables hydro dynamic bearing forming was developed. It consists of power train system, frequency forming system, manufactured Die-set, and controller of desktop forming system. The desktop micro forming system is focused on a higher load capacity and a shorter forming time than conventional system. Therefore it was designed for power train capability and load condition of Ball Screw. Moreover, a Piezo actuator was installed to make accurate machining possible, however, the Piezo actuator generate noise and vibration. Thus we performed the analysis of dynamic characteristics through the experiment about developed system in order to reduce such problems and discuss the alternative methods.

ADPCM 통신을 위한 ISDN 기본율 접속구조

홍진표,허재헌,권원현 안양대학교 자연과학연구소 1995 自然科學硏究 Vol.2 No.-

비저지 시스템을 강력하게 추진하려는 전송설비와 통신망에 저속 코딩 기술이 출현하고 있다. 본 논문에서는 하나의 국제 표준 ISDN 기본율 접속을 통한 ADPCM 음성전송을 위하여 스위치 액세스 구조를 제안하였다. 제안한 구조에서는 2개, 3개 또는 4개의 음성 터미날과 데이타 터미날이 접속을 통하여 동시에 동작될 수 있다. 다양한 기술적 내용을 논의하였으며 제안한 기본율 접속구조, 기본율 S와 T 접속 비트 프레밍 요구와 Q.931 호 제어와 새로운 구조에 필요한 회선할당 절차를 논의하였다. 연구결과 기존 ISDN 스위치에서 제안한 구조로 갱신하는데 비교적 간단한 하드웨어 추가로 될 수 있고 표준 ISDN S와 T접속은 그대로 유지된다. This paper proposes a switch access architecture for Adaptive Differential Pulse Code Modulation voice transimssion over a single international standard Inetegrated Services Digital Network, Basic Rate Interface. In this proposed architecture, data terminals with two voice terminals, three voice terminals, or four voice terminals can be operated simultaneously through the interface. Various technical topics are dicussed : the proposed Basic Rate Interface architecture. BRI S and T interface bit framing requirements and the Q.931 call control and channel assignment procedures required for the new architecture. The study results show that relatively simple additional hardware could be used to upgrade an existing ISDN switch to this proposed architecture and the standard ISDN S and T interfaces remain intact.

리비아 대수로공사 지역의 지반특성

홍원표,남정만,김시현,이재호 중앙대학교 기술과학연구소 1996 기술과학연구소 논문집 Vol.26 No.-

리비아 사막지역의 지반특성을 연구하기 위하여 리비아 1단계 대수로공사가 실시된 지역의 지반특성을 검토하였다. 본 연구에서는 Sarir 취수원에서 Ajdabiya 저수조를 경유하여 Sirt 저수조까지의 대수로 공사지역을 따라 실시된 실내시험과 현장시험결과를 포함하고 있다. 이 지역은 내륙지역(Sarir 취수원에서 Ajdabiya 저수조까지)과 해안지역(Ajdabiya 저수조에서 Sirt 저수조까지)으로 구분하여 연구된다. 본 연구결과, 지표면 부근에 있는 모암(Cap rock)은 주로 Caliche나 석회사암(Calcarenite) 성분을 많이 띠고 있고, 이들의 깊이에 따른 강도변화는 발견할 수 없었다. 또한 모래에 대한 Ncl도 깊이에 대한 변화를 발견할 수 없었으나 이들을 종류별로 분류하였을 경우, N치가 약간 증가하는 추세를 보였다. 끝으로 해안지역의 점토에서는 지표면부근에서 조금 과압밀된 경향을 볼 수 있었으며, 내륙지역의 점토에서는 대단히 높은 팽윤포텐셜이 관찰되었다. To study geotechnical properties on Sahara desert of Libya, geotechnical characteristics in the region of the Great Man-made River Project were reviewed. A series of field and laboratory tests were carried out along the route of the conveyance lines from Sarir well field to Sirt end reservoir through Ajdabiya holding reservoir. In the view of geotechnical aspect, the research subject area can be divided into two areas ; one is the inland area(from Ajdabiya holding reservoir to Sirt reservoir). The results of this study showed that the cap rocks nearby ground surface were generally composed of caliche or calcarenite and variation of its strength according to depth could not find. Also, N value in sand did not show a trend of variation with depth however, the N value in the classified soil reveals tendency to increased. The clay of ground surface in the coastal area was slightly overconsolidated due to the desiccation of the surface soils. The clay in the inland area had high swelling potential.