전자상거래 비즈니스 전략에 관한 연구

황진호,서병삼,한계섭 동아대학교 정보기술연구소 2002 情報技術硏究所論文誌 Vol.10 No.1

Company's growth is the development(or growth) of the connected industry and is closely affected by its development. The lower the entrance barrier of the relevant industry is , the easier this phenomenon comes. Because the change and the evolution is more speedy in the related industry, and the rivalry between the companies deepens rapidly, the industry that the entrance barrier is low has to change continuously for survival with its company's growth policy. In this article, with considered the natural-history paradigm on the development of the online transaction environment that has already been made a research, we divide the development stage of the internet business company and study the impulsive method with its result.

하수슬러지의 산과 초음파 처리에 따른 ECP(exocellular polymers)의 거동이 탈수성과 침강성에 미치는 영향

황선진,정규호,황규대 대한상하수도학회 2002 상하수도학회지 Vol.16 No.6

The effects on dewaterability and settlability of wastewater sludge according to acid and ultrasonic pretreatment which was expected to change ECP (exocellular polymers) compounds in the sludge and bulk solution was investigated. Though ECP which attached to the sludge could stimulate coagulation of sludge particles by bridging effect, but ECP in the bulk solution deteriorated dewaterability and settlability of the sludge on the contrary. That is as the pH of the solution was decreased to 3 gradually by acid treatment, proportionally ECP in the bulk solution was attached to the sludge flocs and resulted in improvement of dewaterability and settlability of the sludge. In case of ultrasonic pretreatment, with proportional to the intensity and duration of ultrasonic application, ECP was detached and extracted from sludge flocs and these phenomena deteriorated dewaterability and settlability. Also because of the increasement of minute sludge particles according to ultrasonic, dewaterability became so much the worse.

쌍방향 Compunication Local Network 구축과 활용

최계호,김용현,이형민,김정숙,황용하 대구산업정보대학 2001 논문집 Vol.15 No.-

Since we are in the transitory era from the age of industrialization to the age of information, it is necessary to accomplish an effective localization of the information. Accordingly, the college tries to construct the bi-directional Communication Local Network so that we can provide the local design companies with technical information and that we can achieve the characterization of the college and its differentiation from the local colleges, which will help us produce the better professionals and eventually provide us the foothold that will make the college a heralding force of the national development and the localization of the information. With the CLN research center, the college can play a key role in providing the necessary information and technologies for the design-related companies in Kyeongsangbuk Province and become a corner stone for the localization of the information and the information-oriented nation.

순시 공진 전압 합성형 DC-DC 컨버터에 관한 연구

이상호,이봉섭,정도영,황계호,남승식,노채균 嶺南大學校 工業技術硏究所 1998 工業技術硏究所論文集 Vol.26 No.2

This paper describes a DC-DC converter connected two unit inverters, a half-bridge high frequency resonant inverters, at the input with parallel. It estimated characteristics such as the average power, the average output voltage etc, for the design of the device with the normalized parameter values. Also, This paper confirms a rightfulness of circuit analysis by comparing a simulation and experimental results of proposal converter. The proposed paper certified that the theoretical waveforms are equal to the experimental waveforms. In the future, it is expected that proposal converter can be applicated for the system of fixed DCvoltage source.

ZVS를 이용한 풀 브릿지 단일 전력단 고주파 공진 AC-DC 컨버터의 특성해석

남승식,황계호,오경섭,원재선,조규판,김동희 嶺南大學校 工業技術硏究所 2003 工業技術硏究所論文集 Vol.31 No.2

This paper proposes a single-stage high frequency resonant AC-DC converter using zero voltage switching with high input power factor. The proposed high frequency resonant converter ingegrates a half bridge boost rectifier as power factor corrector(PFC) and half resonant converter into a single stage. The input stage of the half bridge boost converter is working in discontinuous conduction mode(DCM) with constant duty cycle and variable switching frequency. Therefore, high power factor is achieved naturally. The results of simulation using the Pspice have demonstrated the feasibility of the proposed AC-DC converter. The proposed converter will be able to be practically used as power supply.

자갈함량과 질소시비량이 고랭지 배추재배시 침투수에 의한 질소용탈 및 생육에 미치는 영향

박철수,이계준,정영상,주진호,황선웅 한국환경농학회 2005 한국환경농학회지 Vol.24 No.1

고랭지 배추재배지의 성토재로 사용되고 있는 석비레는 모래와 자갈함량이 높아 토양침식과 양분용탈의 주 요인이 되고 있어 본 연구는 자갈함량에 따른 배추수량과 질소의 용탈양상을 구명하고자 pot 시험을 수행하였다. 시험 결과, 배추의 생체수량은 자갈의 함량이 증가할수록 감소하는 경향이었고, 특히 질소시비량 240 kg/ha 구에서는 현저한 수량감소를 보였다. 질소시비량 60 kg/ha 구에서는 자갈함량 30%, 질소시비량 120 kg/ha 구에서는 자갈함량 50%를 변환점으로 하여 배추수량이 급격히 감소하였다. 배추의 생육장해는 질소시비량이 240 kg/ha인 구에서는 대부분 위조현상이 나타났으며 결구 초기인 8월 초순에는 자갈함량이 50% 이상이 되면 질소시비량을 ha당 120 kg만 시용해도 50% 이상이 위조현상을 보였다. 침출수의 암모늄태 질소는 자갈함량과 질소시비량이 많을수록 침출수의 농도가 높아지는 경향을 보였는데, 특히 배추의 고사가 발생한 30% 이상의 자갈함량과 질소시비량 240 kg/ha인 처리구의 농도는 139-339 mg/L이었다. 침출수의 질소용탈량은 자갈함량에 따라 정의 상관관계를 보였고, 자갈함량이 10% 증가될 때마다 pot당 0.14g씩 증가하여 자갈함량이 10%일 때에 비하여 자갈함량이 30%가 되면 약 3.8배 증가하였다. 배추재배 시험 후 토양의 화학성은 NH₄-H 농도와 pH는 처리간에 일정한 경향을 보이지 않았고, NO₃-N 농도는 자갈함량 30%까지는 증가하다가 50%부터는 감소하는 경향을 보였다. 사양토에서 자갈의 함량이 30%일 때 질소비료 240 kg/ha, 자갈함량이 50%일 때 질소비료 120 kg/ha을 시용하면 배추의 생육장해를 가져올 수 있다. 따라서 이러한 토양에 시비를 하게 되면 염류장해와 위조현상을 초래하므로 토양유실이 심한 고랭지는 특수환경을 고려한 시비기준이 설정되어야 할 것으로 판단된다. Continuous monocropping of Chinese cabbage in Gangwon highland increased gravel and sand contents due to surface soil erosion. Nutrient leaching and Chinese cabbage growth were investigated with different treatments of gravel contents and nitrogen application levels by using 0.5 m²Wagner pots. Gravel contents were 0, 10, 30, 50, 70, and 90%(w/w), nitrogen application levels were 60, 120, and 240 kg/ha, and manure compost application rate was 15 ton per hectare, respectively. Wagner pots were filled with loamy sand soil mixed with 5 cm-sized gravels. Fresh weight of Chinese cabbage was decreased as gravel contents in soil increased, and particularly severely decreased at 240 kg-N/ha. Yields of Chinese cabbage were remark-ably decreased at the rate of 60 kg-N/ha with 30% gravel content and 120 kg-N/ha with 50% gravel content. Most of Chinese cabbages were severely wilted by heavy N application at the rate of 240 kg-N/ha in the middle of growth stages regardless of gravel contents, while about 50% of Chinese cabbage showed wilting symptom in the treatment of more than 50% of gravel contents and 120 kg-N/ha. N content in leachate in-creased as gravel content and N application increased. The relationship between gravel content and N con-tents showed linear regression: N in leachate = 0.014(gravel content) -0.039 (r = 0.961). Particularly, NH₄-N contents in leachates with more than 30% gravel content and 240 kg-N/ha ranged from 139~339 mg/L. Chinese cabbage growth in loamy sand soil containing 30%, and 50% gravel contents could be adversely affected by N application at the rate of 240, and 120 kg-N/ha, respectively.

일산화탄소 및 고압산소의 폭로가 흰쥐의 제2형 폐포세포와 사구체에 미치는 영향에 관한 연구

백두진,정호삼,이계훈,황세진,전영호,전영희 한양대학교 의과대학 1997 한양의대 학술지 Vol.17 No.2

The present study was performed to investigate the ultrastructural changes of the type Ⅱ pneumocyte in the lung and that of the glomerulus in the kidney after carbon monoxide(CO) or hyperbaric oxygen (HBO) exposure. The male Sprague-Dawley rats, weighing about 200gm, were used as experimental animals. The animals were divided into CO exposure group, air exposure after CO exposure group, HBO exposure group and HBO exposure after CO exposure group. After single CO and HBO exposure (3790ppm), the specimen of lung and kidney were obtained. According to routine method, EM preparations were made and observed with electron microscope. The results obtained were as follows ; 1. Slight disruption of the mitochondrial membrane was observed in alveolar type Ⅱ pneumocyte, after single CO exposure. 2. In all experimental groups except CO exposure group, decrease in number and atropy of rough endoplasmic reticulum, disruption of double membrane and crista of mitochondria and vacuolar degeneration of lamellar bodies in alveolar type Ⅱ pneumocytes were observed. 3. In all experimental groups, fusion of the pedicles of podocytes, and obliterations of the endothelial fenestrations were observed. These results suggested that CO and HBO exposure may induced the ultrastructural damages in the alveolar type Ⅱ pneumocyte and the glomerulus.

비접촉 전원장치에 적용한 직 · 병렬 공진형 DC/DC 컨버터의 특성해석

황계호(Gye-Ho Hwang),이영식(Yeung-Sik Lee),방덕제(Deok-Je Bang),문인호(In-Ho Moon),남승식(Seung-Sik Nam),배영호(Young-Ho Bae),김동희(Dong-Hee Kim) 대한전기학회 2005 대한전기학회 학술대회 논문집 Vol.2005 No.7

Stocker 시스템에 적용한 고효율 비접촉 전원시스템 개발

황계호(Gye-Ho Hwang),김원곤(Won-Gon Kim),윤종보(Jong-Bo Yun),문인호(In-Ho Moon),이봉섭(Bong-Seob Lee),민병재(Byung-Jae Min),김동희(Dong-Hee Kim) 한국조명·전기설비학회 2010 조명·전기설비학회논문지 Vol.24 No.2

최근, LCD(Liquid Crystal Display) 산업에서 클린룸의 규모가 커짐에 따라 Stocker 시스템의 사이즈가 커지고 길이가 장거리화 되고 있다. 이에 제조업체는 생산수율을 높이기 위해 Stocker 시스템의 전체 택타임을 줄이기 위한 방안으로 Stocker 시스템의 속도 증가와 고유가 시대에 여러 장비들에 대한 에너지 절약을 통한 공장 운영비용이 최소화되도록 요구하고 있다. 따라서 본 논문은 차세대 Stocker 시스템의 에너지 절감과 이송 속도증가에 따른 고효율 비접촉 전원시스템(CPS, Contactless Power Supply)의 최적설계를 제안하고, 에너지 절감을 위한 비접촉 전원시스템의 시제품을 제작하여 부하인 크레인의 여러 운전 패턴에 따른 비접촉 전원시스템의 실증시험과 입/출력 특성, 효율 개선에 따른 최적화로 개발된 비접촉 전원시스템의 에너지 절감 효과에 대하여 서술하였다. Recently, As increasing cleanroom size, Stocker system is trending the large size and long distance for LCD material transfer system. In order to rise a rate of production, the manufacturer are on the decrease of total tact time with Stocker system. And the manufacturer are requested to high speed of next generation Stocker system. Also manufacturers for the high oil prices through energy-saving conservation to minimize plant operating costs are required. Therefore, this paper propose optimal design of high efficiency Contactless Power Supply(CPS) system about high speed and energy savings of next generation Stocker system. This paper proposes CPS system is applied in the long distance and straight section with Stocker system for energy savings. The test results of input/output characteristic and efficiency of CPS system on operating pattern of Stocker system were analyzed, and proved the applicability on commercial use.

가스 제품에 적용한 제어 시뮬레이션에 관한 연구

황계호(Gye-Ho Hwang),김은영(Eun-Young Kim),김홍용(Hong-Yong Kim),김경신(Kyoung-Shin Kim),김윤(Youn Kim),황나희(Na-Hee Hwang),이봉섭(Bong-Seob Lee) 한국조명·전기설비학회 2021 한국조명·전기설비학회 학술대회논문집 Vol.2021 No.5