DEMS(Diethoxymethylsilane) precursor를 이용한 PECVD 저유전물질 박막증착연구

강민구,김대희,김영철,서화일,Kang, Min-Goo,Kim, Dae-Hee,Kim, Yeong-Cheol,Seo, Hwa-Il 한국반도체디스플레이기술학회 2008 반도체디스플레이기술학회지 Vol.7 No.4

We studied deposition of low-k SiOCH dielectric film by PECVD. DEMS(diethoxymethlysilane) precursor, which has two ethoxy groups along with one methyl group attached to the silicon atoms, was used as precursor. The SiOCH film was deposited as a function of oxygen flow rates ranging from 0 to 100sccm. The deposition rate($\AA$/min) of SiOCH film was increased due to the increase of oxygen radical as a function of $O_2$ flow rates. The dielectric constant was decreased from 3.0 to 2.77, as the film was annealed at $450^{\circ}C$ for 30 min. So, it could account that the dielectric constant changes sensitively with $O_2$ flow rates. Also, the leakage current of the annealed film exhibited stable curve than that of asdeposited. These results were caused by the increase of Si-O-Si group and decrease of Si-CH group and OH group within the film by annealing.

WEPP 모형을 이용한 밭포장과 밭유역의 토양 유실량 추정

강민구,박승우,손정호,강문성,Kang, Min-Goo,Park, Seung-Woo,Son, Jung-Ho,Kang, Moon-Seong 한국농공학회 2004 한국농공학회논문집 Vol.46 No.1

The paper presents the results from the applications of the Water Erosion Prediction Project (WEPP) model to a single plot, and also a small watershed in the Mid Korean Peninsula which is comprised of hillslopes and channels along the water courses. Field monitoring was carried out to obtain total runoff, peak runoff and sediment yield data from research sites. For the plot of 0.63 ha in size, cultivated with com, the relative error of the simulated total runoff, peak runoff rates, and sediment yields using WEPP ranged from -16.6 to 22%, from -15.6 to 6.0%, and from 23.9 to 356.4% compared to the observed data, respectively. The relative errors for the upland watershed of 5.1 ha ranged from -0.7 to 11.1 % for the total runoff, from -6.6 to 35.0 % for the sediment yields. The simulation results seem to justify that WEPP is applicable to the Korean dry croplands if the parameters are correctly defined. The results from WEPP applications showed that the major source areas contributing sediment yield most are downstream parts of the watershed where runoff concentrated. It was suggested that cultural practice be managed in such a way that the soil surface could be fully covered by crop during rainy season to minimize sediment yield. And also, best management practices were recommended based on WEPP simulations.

저수지 취수시설의 공기관을 통한 공기연행에 대한 실험적 연구

강민구,박영진,김지성,Kang, Min Goo,Park, Young Jin,Kim, Ji Seong 대한토목학회 2013 대한토목학회논문집 Vol.33 No.1

본 연구에서는 저수지 취수탑에 연결된 방류관의 게이트 직하류에서 발생하는 공기연행현상에 영향을 미치는 인자들을 수리모형실험을 통해서 파악하였다. 또한 측정자료의 $\frac{Q_a}{Q_w}$와 $Fr_g-1$ 관계를 이용하여 공기관의 연행공기량 추정식을 개발하였다. 측정된 자료는 게이트 하류 흐름에 따라 구분되었으며, 개발된 실험식은 만관 흐름인 경우에 $\frac{Q_a}{Q_w}=0.0304(Fr_g-1)^{1.0622}$, 자유수면 흐름인 경우에 $\frac{Q_a}{Q_w}=0.0271(Fr_g-1)^{1.8205}$이었다. 측정 자료와 기존 연구결과들의 비교를 통해서 측정 자료가 기존 실험식의 추정 결과와 유사한 분포를 나타내고 측정 자료의 신뢰성이 확보된 것으로 파악되었다. 또한 공기관 부근에서 발생하는 공기연행현상은 게이트 하류에서 발생하는 사류 특성으로부터 영향을 받는 것으로 나타났다. 최종적으로 하류 만관 흐름 조건에 대한 실험식은 공기관 설계에 적용이 가능한 것으로 사료된다. In this study, factors that affect the air entrainment within a closed conduit by air drawn in through an air vent are investigated using a hydraulic scale model, which represents a gated circular conduit system connected to the intake tower of an irrigation reservoir. In addition, using data obtained during the hydraulic experiments, experimental equations are developed to estimate the amount of air drawn in through the air vent. In case of pressurized flow conditions downstream of hydraulic jumps, the relationships between $\frac{Q_a}{Q_w}$ and $Fr_g-1$ of the data form a experimental equation, $\frac{Q_a}{Q_w}=0.0304(Fr_g-1)^{1.0622}$; in case of free surface flow conditions, $\frac{Q_a}{Q_w}=0.0271(Fr_g-1)^{1.8205}$. Comparing two data sets observed under the two flow regimes with the results of previous researchers, patterns of the data sets are similar to the results estimated using the equations presented previously, and this indicates that the quality of the data obtained during the hydraulic experiments is ensured. In addition, it is revealed that air entrainment phenomena in the regions close to air vents are affected by the characteristics of supercritical flows downstream of gates. Finally, it is concluded that the equation developed for pressurized flow conditions can be applied to design of air vents.

메가픽셀급 초광각 렌즈의 왜곡영상 보정과 화질분석

강민구,이재선,이우섭,Kang, Min-Goo,Lee, Jae-Son,Lee, Ou-Seob 한국정보통신학회 2013 한국정보통신학회논문지 Vol.17 No.3

본 논문에서는 렌즈화각 150도 이상의 메가 픽셀급 렌즈가 획득한 영상이 통형 왜곡을 보정하는 광각렌즈 모듈의 설계를 제안한다. 이로서 초광각 렌즈에서 획득된 영상은 WDR(Wide dynimic range) 2메가급 CMOS 이미지 센서데이터를 통해 초광각 영상의 왜곡영상을 보정하는 2 메가급 카메라 모듈의 왜곡영상의 화질을 개선한다. In this paper, the lens module of mega pixel type was designed for barrel distortion calibration due to the barrel distortion of ultra wide angle. And the performance of this camera module was improved with the images from wide dynamic range 2 megapixel CMOS image sensor.

국내 농업용수로 시스템에 적합한 유량측정법

강민구,김진택,Kang, Min-Goo,Kim, Jin-Taek 한국관개배수위원회 2009 한국관개배수논문집 Vol.16 No.1

논 지구의 배수로 부정류 흐름 모의를 위한 모델링 시스템

강민구,Kang, Min Goo 한국농공학회 2014 한국농공학회논문집 Vol.56 No.2

A modeling system is constructed by integrating an one-dimensional unsteady flow simulation model and a hydrologic model to simulate flood flows in drainage channel networks of paddy field districts. The modeling system's applicability is validated by simulating flood discharges from a paddy field district, which consists of nine paddy fields and one drainage channel. The simulation results are in good agreement with the observed. Particularly, in the verification stage, the relative errors of peak flows and peak depths between the observed and simulated hydrographs range 8.96 to 10.26 % and -10.26 to 2.97 %, respectively. The modeling system's capability is compared with that of a water balance equation-based model; it is revealed that the modeling system's accuracy is superior to the other model. In addition, the simulations of flood discharges from large-sized paddy fields through drainage channels show that the flood discharge patterns are affected by drainage outlet management for paddy fields and physical characteristics of the drainage channels. Finally, it is concluded that to efficiently design drainage channel networks, it is necessary to analyze the results from simulating flood discharges of the drainage channel networks according to their physical characteristics and connectivities.

관개지구의 관행 물관리를 고려한 저수지 용수공급량 추정

강민구,오승태,김진택,Kang, Min Goo,Oh, Seung Tae,Kim, Jin Taek 한국농공학회 2014 한국농공학회논문집 Vol.56 No.5

The DIROM (Daily Irrigation Reservoir Operation Model) was modified to estimate amounts of water release from reservoirs, considering customary irrigation water management practices, such as water supply for puddling and transplanting paddy rice from seeding beds and mid-season drainage. The applicability of the modified model was investigated by simulating amounts of water release from three study reservoirs: Hwamae, Ogi, and Doya Reservoirs. In terms of annual amounts of water release, the relative errors between the observed and simulated values in 2012 and 2013 ranged -26.20 % to 10.28 % and 4.90 % to 30.06 %, respectively; in case of reservoir water levels, the RMSE values ranged 0.45 m to 1.34 m and 0.40 m to 1.27 m, respectively. Also, it was revealed that the model provided better simulation results for monthly water releases than the original model. In addition, the model presented better performance in simulating 10-day amounts of water release from April to June. However, the model had still significant errors in the simulation results from July to September because the reservoirs were practically operated to adapt to water management circumstances. Finally, it is concluded that the modified DIROM can estimate the amounts of water release from reservoirs, reflecting irrigation water management customs in paddy-field districts. To achieve higher prediction accuracy of the model, it is necessary to incorporate practical reservoir operation rules into the model.

광대역무선채널에서 다중반송파 적응변조시스템의 궤환정보 감소알고리듬

강민구,임승주,천현수,강창언,Min-Goo, Kang,Soong-Ju, Im,Hyun-Su, Cheon,Chang-Ean, Kang 통신위성우주산업연구회 2001 Joint Conference on Satellite Communications Vol.2001 No.-

본 논문에서는 다중 반송파 적응 변조기술을 적용한 무선 데이터 전송 시스템에서 궤환정보를 감소하는 알고리듬을 제안하고, 성능을 분석한다. 일반적인 직교 주파수 분할 다중화 (OFDM :orthogonal frequency division multiplexing) 방식은 모든 부반송파를 통해 전송되는 신호의 정보량을 같게 설정한다. 하지만 제안된 다중 반송파 적응 변조 시스템은 채널의 상태 또는 주어진 에러 확률에 따라 부반송파를 통해 전송되는 신호의 정보량을 다르게 함으로서 원하는 품질의 전송상태를 유지하면서도 데이터의 전송률을 최대화할 수 있다. 또한 데이터의 전송률과 전송 상태를 고정하면서 최소의 소비전력으로 전송할 수 있다. In this thesis a wireless data transmission system has been proposed and analysed that uses the multi-carrier technique with the adaptive modulation scheme. In general, the OFDM(Orthogonal Frequency Division Multiplexing) system is assigning a same amount of information to all sub-carriers in a wireless data transmission. In the proposed system, the different amount of information is assigned to each sub-carrier depending on the state of channel and the target probability of error of system. With the proposed scheme, the transmission rate can be maximized with the fixed power and the required power to transmit the information can be minimized with the target probability of error of system.

IPv6기반의 UFID(지형지물유일식별자)통신시스템 설계

강민구,Kang, Min-Goo 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.3

본 논문에서는 국가 통합 지리정보시스템(GIS)용 데이터 모델과 인터넷 주소정보를 지리정보로 결합하여 인터넷상에서 원하는 위치정보를 찾을 수 있는 지형지물유일식별자(UFID, Unique Feature Identification)와 발생지리정보체계(GIS)를 연결하는 UFID의 개념을 무선통신에 활용하기 위한 새로운 IPv6기반의 인터넷 주소체계 구축과 관리방안을 연구한다. 본 연구의 결과로 전국의 1,500,000여개의 건물에 대한지형지물을 표시하기 위해 IPv6의 주소관리체계는 6바이트의 코드구성으로, UFID에 의한 지형지물식별체계에서 IPv6의 128비트로 URI(Uniform Resource Identifier)식별체계를 제안하였으며, 권역/광역/기초/건물위치/건물정보의 식별체 계법과 DNS관리방안과 UFID사용 환경을 고려한 UFID 통신시스템 설계방안을 제안한다. In this paper, the design of URL structures and managements for UFID(Unique feature Identification) based wireless communications is presented with the combination of GIS and URL address informations. As a result of IPv6 based UFID wireless communications, new methods for URI(Uniform Resource Identifier) informations and UFID communication systems are proposed with a 6byte coded 128-bit IPv6 DNS system for the presentation of 1,500,000 korean buildings.

영향요인을 고려한 댐 용수공급능력 추정 회귀모형

강민구,이광만,Kang, Min Goo,Lee, Gwang Man 한국수자원학회 2012 한국수자원학회논문집 Vol.45 No.11

본 연구에서는 댐 용수공급능력에 영향을 미치는 요인들을 요인분석 통계기법을 사용하여 추출하였으며, 그 결과를 이용하여 댐 용수공급능력 추정을 위한 다중회귀모형을 개발하였다. 21개 다목적댐과 12개 생공용수전용댐을 대상으로 하였으며, 다목적댐과 생공용수전용댐으로 구분하여 요인분석을 수행하였다. 댐 용수공급능력에 영향을 미치는 변수로 유역면적, 유입량, 유효저수량, 생공용수량 등급, 농업용수량 등급, 하천유지유량 등급, 하천관리 등급, 평균강우량 등급을 선정하였다. 변수들의 상관계수 행렬점검, Bartlett의 구형성 점검, KMO 표본적합도 점검을 실시하여 변수들의 요인분석에 대한 적합성을 확인하였다. 변수들은 다목적댐의 경우 3개 요인, 생공용수전용댐의 경우 2개 요인으로 분류되었으며, 요인들을 Varimax법을 사용하여 회전시켰다. 요인분석 결과는 댐 용수공급능력에 영향을 미치는 변수들이 합리적으로 선정되었고, 이들이 요인으로 적절하게 분류되었음을 보여주었다. 요인점수를 설명변수로 사용하여 연간용수공급량을 추정할 수 있는 다중회귀모형을 개발하였으며, 개발된 모형의 정확성을 평가하고 적용방법을 제시하였다. 결론적으로 댐 용수공급능력에 영향을 미치는 것으로 파악된 변수 및 요인은 댐 계획 및 설계에 유용하게 활용될 수 있을 것으로 사료된다. In this study, factors that influence water supply capacities of dams are extracted using factor analysis, and multiple regression equations for estimating water supply capacities of dams are developed using the analysis results. Twenty-one multi-purpose dams and twelve Municipal and Industrial (M&I) water supply dams are selected for case studies, and eight variables influencing water supply capacities of dams, namely: watershed area, inflow, effective reservoir storage, grade on amount of M&I water supply, grade on amount of agricultural water supply, grade on amount of in-stream flow supply, grade on river administration, and grade on average rainfall, are determined. Two case studies for multi-purpose dams and M&I water supply dams are performed, employing factor analysis, respectively. For the two cases, preliminary tests, such as reviewing matrix of correlation coefficient, Bartlett's test of sphericity, and Kaiser-Meyer-Olkin (KMO) test, are conducted to evaluate the suitability of the variables for factor analysis. In case of multi-purpose dams, variables are grouped into three factors; M&I water supply dams, two factors. The factors are rotated using Varimax method, and then factor loading of each variable is computed. The results show that the variables influencing water supply capacities of dams are reasonably selected and appropriately grouped into factors. In addition, multiple regression equations for predicting the amounts of annual water supply of dams are established using the factor scores as explanatory variables, it is identified that the models' accuracies are high, and their applications to determining effective storage capacity of a dam during dam planning and design steps are presented. Consequently, it is thought that the variables and factors are useful for dam planning and dam design.