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.

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.

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.

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.

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.

연약지반상 교대의 측방이동에 대한 대책공법

홍원표,이재호,송영석 중앙대학교 기술과학연구소 2003 기술과학연구소 논문집 Vol.33 No.-

한 도로교량의 교대를 시공한 후 상부거더가 교대 흉백으로 밀려들어가는 현상이 발생 되었다. 이 교량교대를 대상으로 기초연약지반의 특성을 분석하고, 사면안정해석을 실시하여 교대의 측방이동 여부를 판정하여 보았다. 판정결과 교대의 측방이동은 계속적으로 발생될 것으로 예측되어, 합리적인 대책공법을 고찰한다. 여러 가지 대책공법을 분류 · 분석 한 후 본 현장에 적합한 대책공법으로서 성토지지말뚝공법으로 분류되는 파일슬래브 공법이 선정된다. 본 공법은 교대 배면에 말쪽을 설치하여 성토하중을 지지층으로 전달함으로써 연약지반의 측방유동을 억제하는 공법이다. 또한 대책공법 적용 후 교대의 안정성을 확인할 수 있는 현장계측시스템을 도입한다. After construction of bridge abutment of a bridge for roads, steel box girder of bridge was moved into the parapet wall of abutment. Based on analysis of geotechnical characteristics and slope stability, the judgement of lateral movement of bridge abutment on soft ground is performed. As a result of judgement. various countermeasures are analyzed to prevent against the lateral movement of bridge abutment. The pill slab method among the various countermeasures is based on embankment pile which is installed in soft ground to decrease the overburden due to embankments Also, field instrumentation system is installed to observe reinforced effect of the countermeasures and stability of bridge abutment.

씨름선수들의 경력과 체급이 경쟁상태불안에 미치는 영향

홍장표,이재학,이승도 龍仁大學校 體育科學硏究所 1998 體育科學硏究論叢 Vol.8 No.1

The purpose of this study is to analyze effects of athletic careers and weight grades on cognitive competitive state anxiety and physical competitive state anxiety. The study employed 250 university Ssirum athletes who participated in the 28th National Ssirum Championship for federation chairman's flag and the 35th National Ssirum Championship for Presidential Flag. Two hundred twenty response forms out of 250 subjects using CSAI-2 by Martens (1990) were analyzed. Descriptive statistics for mean and standard deviation for weight grades and athletic careers and one way ANOVA for differences among grades and among careers at α= .05. The conclusions are followings. First, athletic careers influenced on cognitive competitive state anxiety, physical competitive state anxiety, and state confidence, Second, weight grades did not influence on cognitive competitive state anxiety, physical competitive state anxiety, and state confidence.

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.

유도선수들의 스포츠자신감 수준이 귀인형태에 미치는 영향

홍재표,차정훈,전승훈 한국스포츠리서치 2005 한국 스포츠 리서치 Vol.16 No.2

The present study was designed to examine the effect of sport-confidence on attributional perceptions across male and female fencers. Judo athletes reported their sport-confidence, attribution perceptions on Sport-Confidence Inventory. CDSⅡ(Causal Dimension Scale Ⅱ) According to the previous research findings related to the theme of the study, it was hypothesized that the independent variables of trait sport-confidence. state sport-confidence influence the dependent variable of attributional perceptions. and the relationships between the two kinds of variables were examined using two-way ANCOVA. The implications of the study are as follows : Firstly. Trait sport-confidence and state sport-confidence of judo athletes significantly affected the locus of contorl dimension. Secondly. Trait sport-confidence and state sport-confidence of judo athletes significantly affected the stability dimension. Thirdly, Trait sport-confidence and state sport-confidence of judo athletes significantly affected the contro lability dimension.