SUSTAIN를 이용하여 상업지구, 위락시설지구의 유출 특성 비교 분석

최동호 ( Dongho Choi ),백상수 ( Sangsoo Baek ),정재운 ( Jaewoon Jung ),김성균 ( Sungkyun Kim ),윤광식 ( Kwangsik Yoon ),박하나 ( Hana Park ) 한국농공학회 2013 한국농공학회 학술대회초록집 Vol.2013 No.-

도시화와 함께 도로, 주거지역, 상업지역 등 불투수면이 증가하고 있으며, 불투수면의 증가는 강우시 유출량 증가와 더불어 배출되는 비점오염원을 증가를 야기 시켰다. 비점 오염관련 전문가들은 부족한 예산, 제한된 자원, 불완전한 정보에 의해 도시개발에 따른 비점오염원의 영향평가 및 비점오염원의 저감 방안 수립에 현실적인 제한을 받고 있으며, 이에 따라 도시개발에 따른 비점 오염원의 적절한 관리를 위해 모델의 사용은 정책결정을 위한 매우 중요한 정보를 생산하게 된다. SUSTAIN은 GIS기반으로, 유역에서의 강우 유출 및 오염물질 이송, 해석, 최적관리기법(습지, 침투도랑, 저류지, 옥상녹화)을 도입 시 오염물질의 저감 예측, BMP 위치 및 규모 선정, 목표수질과 유량을 달성하기 위한 효과적인 비용을 산정 할 수 있다. 본 연구에서는 SUSTAIN모델이 우리나라의 도시환경에 실제로 적용 할 수 있는지를 평가하기 위해 BMP를 설치하지 않은 상태로 모델을 구동하였다. 적용지구인 상업지구 저밀도지역(광주광역시 서구 치평동 상무지구 내 먹자골목)은 불투수면적 85%, 투수면적 15%이며, 분류식 하수관거를 사용하고 있다. 위락시설지역인 어린이대공원(광주광역시 북구 운암동)은 중 불투수면적이 약 37%, 투수면적이 약 63%를 차지하고 있고, 분류식 하수관거를 사용하고 있다. 2008년부터 2012년도까지 상업지구 저밀도 지역 12회, 위락시설지역 10회, 총 22회의 강우사상에 모델을 적용하였으며. 모델 적용 평가 방법으로 R², RMSE, NSE가 사용하였다. 상업지구 저밀도지역의 강우사상의 R², RMSE, NSE의 평균 값은 각각 0.65, 10.23, 0.50 가 나타났고, 위락시설지구 어린이대공원은 강우사상의 R², RMSE, NSE의 평균값은 0.70, 7.79, 0.60로 나타났다. 이 결과는 Ramanrayanan et al(1997)가 제안한 모델평가에서 R²가 0.5 이상이고, NSE가 0.4이상 일 때 모델이 자연 현상을 잘 모의한 것이라는 기준에 충족한 것으로 나타나 SUSTAIN 모델이 우리나라에서 적용하고, 사용할 수 있는 것으로 보인다.

Development and performance test of a micromachined unipolar charger for measurements of submicron aerosol particles having a log-normal size distribution

Park, Dongho,Kim, Yong-Ho,Lee, Sang-Goo,Kim, Chul,Hwang, Jungho,Kim, Yong-Jun Elsevier 2010 Journal of aerosol science Vol.41 No.5

<P><B>Abstract</B></P><P>We designed and evaluated a chip-type unipolar charger based on a micro-electro-mechanical systems (MEMS) process for a compact, portable, inexpensive, and easy-to-deploy instrument to measure real-time aerosol particle size distribution with reasonable accuracy. The charger was evaluated using two parameters: particle loss and charging characteristics which were the product of penetration (<I>p</I>) and average number of charges (<I>n<SUB>p</SUB></I>). Particle losses were below 16.6%, and <I>p</I>·<I>n<SUB>p</SUB></I> was approximately proportional to dp2. After evaluation, the number concentrations and the geometric mean diameters of NaCl aerosol particles were estimated using a method presented in <ce:cross-ref refid='bib13'>Park, An, and Hwang (2007a)</ce:cross-ref> and were compared to scanning mobility particle sizer (SMPS) data. To simulate the charger, a commercial computational fluid dynamics (CFD) software, FLUENT (6.3 version), with external user defined function (UDF) code, was used to solve the electric field, flow field, average particle charge, and particle trajectories. The measured data of particle loss, average particle charge, number concentration, and geometric mean diameter were in good agreement with the results calculated by FLUENT.</P>

Optimization of Controllable Factors in the Aluminum Silicon Eutectic Paste and Rear Silicon Nitride Mono-Passivation Layer of PERC Solar Cells

Park, Sungeun,Park, Hyomin,Kim, Dongseop,Yang, JungYup,Lee, Dongho,Kim, Young-Su,Kim, Hyun-Jong,Suh, Dongchul,Min, Byoung Koun,Kim, Kyung Nam,Park, Se Jin,Kim, Donghwan,Lee, Hae-Seok,Nam, Junggyu,Kang Springer-Verlag 2018 METALS AND MATERIALS International Vol.24 No.3

<P>Passivated emitter and rear contact (PERC) is a promising technology owing to high efficiency can be achieved with p-type wafer and their easily applicable to existing lines. In case of using p-type mono wafer, 0.5-1% efficiency increase is expected with PERC technologies compared to existing Al BSF solar cells, while for multi-wafer solar cells it is 0.5-0.8%. We addressed the optimization of PERC solar cells using the Al paste. The paste was prepared from the aluminum-silicon alloy with eutectic composition to avoid the formation of voids that degrade the open-circuit voltage. The glass frit of the paste was changed to improve adhesion. Scanning electron microscopy revealed voids and local back surface field between the aluminum electrode and silicon base. We confirmed the conditions on the SiNx passivation layer for achieving higher efficiency and better adhesion for long-term stability. The cell characteristics were compared across cells containing different pastes. PERC solar cells with the Al/Si eutectic paste exhibited the efficiency of 19.6%.</P>

Dual Stage Trolley Control System for Anti-swing Control of Mobile Harbor Crane

Dongho Kim,Youngjin Park,Youn-sik Park,Sangwon Kwon,Eunho Kim 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

A work efficiency and safety of Mobile Harbor crane in the open sea condition are considered as serious problem because Mobile Harbor have 6 degree of freedom motion caused by external disturbance such as wave and wind. It is the core technology to suppress the sway and surge motion of containers during loading and unloading operation in this Mobile Harbor project. KAIST Mobile Harbor center proposed and implemented the dual stage control system to resolve this problem. In this paper, we proposed the anti-swing controller using this dual stage control system. To establish the system model, system parameters are characterized by system identification process with respect to the 1/20 scale D4 crane model and the LQR controller for anti-swing was designed based on decoupled of X- and Y-axis and linearized crane model. The performance of the designed anti-swing LQR controller is verified by experiments of 1/20 scale Mobile Harbor crane mounted on a shaky motion platform even though the mode of motion of container was excited.

Terminal tracking control of mobile harbor crane subject to actuator saturation

Dongho Kim,Youngjin Park,Youn-sik Park 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

In this paper, the tracking control of mobile harbor crane at the terminal time with considering actuator saturation is proposed for accurate position control. During loading/unloading operation of mobile harbor crane in open-sea condition, it is difficult to control the container position on the desired position due to an unwanted swing motion and a continuous movement of container ship caused by external disturbances such as wave and wind. Several researches have been already studied to develop to suppress the swing motion of ship-board crane system but the tracking problem to moving target is emerging newly in ocean engineering. The tracking control system of ship-board crane should be designed although this system has complex dynamics, various external disturbances, and the limited power of actuators. In the proposed control system, constrained model predictive control(MPC) with changing input and output constraints in real-time is applied for the only terminal tracking control. The numerical simulations are performed to verify the overall terminal tracking control performances of the proposed constrained MPC.

Rapid and Accurate Measurement of Ideality Factor and Parasitic Resistances of Thin Film Solar Cells

Park, Sungeun,Kim, Soo Min,Park, Se Jin,Bae, Soohyun,Park, Hyomin,Nam, Jung gyu,Lee, Dongho,Yang, Jung Yup,Kim, Dong Seop,Mo, Chanbin,Kim, Young-Su,Kim, Jihyun,Lee, Hae-Seok,Kang, Yoonmook The Electrochemical Society 2018 ECS journal of solid state science and technology Vol.7 No.6

<P>The sunshade method for the measurement of the ideality factor and resistances of solar cells is commonly used in silicon solar cells. However, the method is rarely employed for thin-film solar cells. In this paper, the sunshade method is applied to CIGS solar cells, and it is shown that the three major assumptions of the method remain valid for CIGS solar cells. The extracted parameters are compared to those calculated using other common methods, and the ideality factors and R-s values are quickly determined and found to be nearly the same as those extracted through illuminated I-V fitting and dark I-V fitting. (C) 2018 The Electrochemical Society.</P>

Paralysis of the gastrocnemius medial head differentially affects gait patterns and muscle activity during level and stair ascent locomotion

Park, Dongho,Seong, Yeon-Jae,Woo, Hanseung,Yoo, Beomki,Shim, Dain,Kim, Eun Sang,Rha, Dong-wook Elsevier 2019 GAIT AND POSTURE Vol.72 No.-

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>Prior studies have analyzed the activity of the gastrocnemius (GCM) medial and lateral heads as a single unit because it is technically challenging to separately analyze the function of each component <I>in vivo</I>. However, functional variation between the medial and lateral heads is expected due to their anatomical differences.</P> <P><B>Research question</B></P> <P>What is the independent function of the medial GCM? How does paralysis of the GCM medial head affect gait kinematics?.</P> <P><B>Methods</B></P> <P>Twelve healthy adults (two males and ten females; age: 28.2 [±7.72] years) that were scheduled to undergo neurolysis of the tibial nerve branch supplying the medial head of the GCM for aesthetic calf reduction participated in the study. Gait analysis was performed using a computerized opto-electric gait analysis system to measure kinematic data. Surface electromyography (EMG) was recorded simultaneously during the gait analysis. Surface electrodes were placed on seven muscles. Pre-procedure and 1-week and 3-month post-procedure data were compared using a linear mixed model.</P> <P><B>Results</B></P> <P>During level walking, decreased activity of the GCM medial head did not significantly change gait kinematics. However, a significant increase in GCM lateral head and hamstring activities occurred after a branch nerve block to the GCM medial head. During stair ascent, in contrast to level walking, changes in EMG activity only occurred in the GCM medial head, and post-procedure ankle dorsiflexion angles at the end of the terminal-stance phase significantly increased. Ankle plantarflexion angles during the push-off phase were also decreased when compared with pre-procedure values.</P> <P><B>Significance</B></P> <P>The human body response to dysfunction of the GCM medial head depended on the type of locomotion.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Decreased medial GCM activity did not significantly change kinematics during gait. </LI> <LI> Lateral GCM activity significantly increased after nerve block during gait. </LI> <LI> There was a kinematic change during stair ascent. </LI> <LI> There was no compensatory hyperactivities in the lateral GCM during stair ascent. </LI> </UL> </P>

LASER FLASH PHOTOLYSIS STUDY ON THE PHOTOCYCLIZATION OF N-(O-HALOBENZYL) IMIDAZOLE

Park, Yong-Tae,Hwang, Young-Sun,Song, Woong Song,Kim, Dongho Korean Society of Photoscience 1996 Journal of Photosciences Vol.3 No.2

In connection with our interest on the photochemical properties of heteroaryl halides, which are currently the subject of heterocyclic ring formation and haloarene degradation, we have studied the photochemistry of the haloarene linked to N-heteroarene compounds. Imidazo[5,1-a]isoindole was synthesized from N-(ochlorobenzyl)imidazole or N-(o-bromobenzyl) imidazole in acidic aqueous solution or acetonitrile via the intramolgcular photocyclization (Table 1). This type of reaction provides the synthetic methods for 5- and 6-membered polyheteroatomic heterocyclic ring compounds. However, the reaction mechanism for the intramolecular photocyclization of haloarene tethered heteroarenes has not yet been established. Grimshaw et al. suggested a mechanism for homolyric carbonhalogen bond fission assisted by radical complexation to explain their results in the photocyclization of 5-(2-chlorophenyl)-1,3-diphenylpyrazole. They also reported the detection of acyclohexadienyl intermediate involved in the above reaction. Park et al. reported several transient 'intermediates involved in the laser flash photolysis of N-(o-halobenzyl) pyridinium and N-benzyl-2-halopyridinium salts. Thus we performed the laser flash photolysis study on the photocyclization reaction of N-(o-chlorobenzyl) imidazole to identify the intermediate species involved in the reaction. Here, we report on the preliminary results in the photocyclization reaction of N-(o-halobenzyl)imidazole through the detection of reaction intermediates.

Feasibility Test of Tracking Control to Moving Target in Dual-state Trolley Control System

Dongho Kim,Youngjin Park,Youn-sik Park 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

In this paper, the performance of tracking control algorithm to apply to the mobile harbor(MH) crane trolley control system is verified with 1/20 scale experiment. MH is a novel maritime cargo transfer system which is recently proposed by KAIST. A relative motion between MH and container ship is caused by external disturbances such as wave and wind because loading/unloading operation of MH system is performed in open-sea condition. It is necessary to control the position of containers to the target position in this condition accurately. Using dual-stage trolley control system of MH which is proposed to control the position of trolley independently, the receding horizon controller is designed to track the moving target position. Through the 1/20 scale model experiments as the frequency of reference signal is changing, the feasibility of tracking control of MH crane system is checked.

A Tilted Combined Beam Antenna for 5G Communications Using a 28-GHz Band

Park, Jang-Soon,Ko, Jun-Bong,Kwon, Heon-Kook,Kang, Byung-Su,Park, Bonghyuk,Kim, Dongho IEEE 2016 IEEE antennas and wireless propagation letters Vol.15 No.-

<P>A novel combined beam antenna for 5G communications using a 28-GHz frequency band is proposed, which provides a tilted radiation on an elevation plane. Instead of applying a conventional array technique to produce a scanned beam, two different radiating elements have been combined in order to obtain a relatively wide beam but high gain in a tilted target direction. There are two main radiators; one is a group of microstrip patches, and the other is a waveguide aperture. The patches produce two split strong beams on the azimuth plane. The aperture further increases antenna gain on the elevation plane. Finally, by optimizing the constructive interference between the patches and the aperture, we can obtain relatively high antenna gain even with a wide beam spreading across an azimuthal plane. All experiments show good agreement with the simulation results, which proves the validity of our approach.</P>