공공발주처의 공사감독 업무영역과 비용 분석

조성수,Cho Seong-Soo 한국건설관리학회 2003 건설관리 : 한국건설관리학회 학회지 Vol.4 No.3

건설프로젝트에 있어서 공사감독은 공정관리, 품질관리 안전관리, 원가관리에 중요한 영향을 미친다. 그러므로 건설공사의 초기단계에서부터 감독의 지속적인 관리활동이 필요하다. 그러나 국내 공공 건설공사에서 감독의 업무량과 비용에 대한 평가가 미비한 실정이다. 또한 공사 감독이 초기단계에서부터 지속적인 관리활동이 가능한지에 대해서도 회의적인 시각이 상존하고 있다. 본 연구에서는 우리나라 공공발주처에서 시행하는 공사의 감독 업무와 외국에서의 공사감독의 관리활동을 비교$\cdot$분석하였다. 또한 국내 건설공사에서 감독에 소요되는 비용과 감독을 대체한 감리원을 활용하였을 때의 비용을 평가하였다. 이를 통하여 향후 감독업무의 개선이 가능하고 비용적 측면에서 인건비 등 공사 간접비의 절감을 기할 수 있겠다. In the construction project, construction supervisor influences greatly the construction managements such as process management, quality management, safety management, and cost management. Therefore, from the first stage of the project, the managing activities of the supervisor are consistently needed. But the assesment of supervisor's work and cost has not been made enough in the public construction project. And there have been doubts as to whether a supervisor can take a consistent managing activity from the early stage of the project. Accordingly, the works between Korean supervisor and foreign supervisor in their public corporations are analyzed and compared in this paper. And the evaluation is made each of the cost for supervisor and the cost for engineer as a substitute of supervisor in construction project. This study is believed to contribute to improving the supervisor's work and reducing the personnel expenses and construction indirect cost.

배전선로의 분산 전원 상시 연계용량 기준 상향 타당성 연구

조성수,심준보,임현옥,김현진,김성만,주상도,송종협,Cho, Sung-Soo,Sim, JunBo,Lim, Hyeon-Ok,Kim, HyeonJin,Kim, Seong-Man,Ju, Sang-Do,Song, JongHyup 한국전력공사 2019 KEPCO Journal on electric power and energy Vol.5 No.4

정부의 재생e 3020 이행계획 및 제 8차 전력수급 기본계획과 함께 국내 분산 전원 연계 사업이 활발하게 진행되고 있다. 특히 2016년 10월 시행된 1 MW이하의 분산 전원 접속 보장 제도의 시행 이후, 배전 계통의 분산 전원 연계 신청이 급증함에 따라 송배전 설비부족으로 분산 전원 접속 지연이 일어나는 문제와, 이로 인해 국내 분산 전원의 70 %가 연계되어 있는 배전 계통의 신증설 투자비가 증가하는 문제가 이슈로 부각되고 있다. 현재 배전 계통의 분산 전원 수용력(hosting capacity) 확보 방법은 물리적인 배전 설비 추가 확충 이외에는 대안이 없는 것이 현실인데, 이러한 방식은 아래와 같은 어려움이 따른다. 첫째, 분산 전원의 대다수를 차지하는 태양광은 일조량이 풍부하고 지가가 저렴한 야외, 산악지역에 보급되므로 배전선로 경과지 확보가 점점 어려워지고 있다. 이로 인해 지중 구간이 증가하여 공사비가 증가하며, 태양광 야외 지역 위치로 공사 거리, 기간이 증가하게 된다. 둘째, 지자체의 공사 인허가 비협조 사례가 증가하여 이로 인해 공사가 지연되어 민원이 야기된다. 셋째, 배전선로 공사 자체에 1년 이상의 공사기간이 소요되므로 분산 전원을 적기에 접속시킬 수가 없으며, 넷째, 접속 신청은 지속 증가하므로 이에 따라 배전 설비 확충 비용 또한 지속 증가 할 수 밖에 없다. 이렇게 물리적 설비확충으로 발생하는 문제에 대응하여 접속 대기를 최소화하면서도 공사(투자비)를 최소화 할 수 있는 방안은 설비이용률을 극대화하는 것이며, 본 연구는 이러한 고민에서 시작되었다. 그러므로 본 논문에서는 현재 배전 계통의 분산 전원 연계 현황, 태양광 최대 출력 실적, 최소 부하, 선로 특성의 분석을 통해 배전선로의 분산 전원 상시연계용량 기준을 상향하기 위한 타당성을 검토하였으며, 배전선로의 분산 전원 상시연계용량 기준을 위한 상향(안)을 제시하였다. With Korean Government's Renewable energy 3020 plan and 8th Basic plan for long-term power supply, renewable energy industries in Korea are active and catching attention from many relevant industry's relations. Especially with Interconnection guarantee policy established in Oct, 2016, DERs interconnection delay due to lack of allowable distribution hosting capacity is happening and reduction of reinforcement cost for distribution system where 70 % of DERs in South Korea are installed became one of important issues of KEPCO. Therefore, KEPCO needed to extract reasonable solutions to increase feasible hosting capacity of distribution feeders in order to reduce reinforcement cost under the condition of no matter in distribution system operation. This paper proposes feasible hosting capacity of distribution feeders that can be adopted and the status of DER installation in distribution system, PV output data, minimum load in distribution feeders as well as capacity of distribution lines have been investigated and analyzed in proof of the proposal.

온도-엔탈피 관계를 이용한 응고과정의 유한요소 해석

조성수,하성규,Cho, Seong Soo,Ha, Sung Kyu 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.10

A finite element method is developed for calculating the temperature and enthalpy distribution and accordingly the solid, liquid and mushy zone in a three-dimensional body subjected to any heat boundary conditions. The method concurrently consider both temperature and enthalpy for consideration of the latent heat effect, differently from other methods of using a special energy balance equation for solving a mushy zone. The developed brick element has eight nodes with one degree of freedom at each node. The numerical method and procedure are verified using the results of one and two dimensional analytic solutions and by other researchers. It is shown that the present method presents a consistent and stable results in either abrupt or ranged phase change problems. Moreover, the numerical results by the present method are hardly effected by the calculation time steps which otherwise are difficult to determine in most phase change problems. Finally, as a three-dimensional application, a T-shaped body of a phase change is presented and the temperature and enthalpy variation along the time are solved.

성인 혈전성 미세혈관병증에 관한 임상적고찰

조성수(Seong Soo Cho),박용일(Yong Il Park),박근용(Keun Yong Park),박성배(Sung Bae Park),김현철(Hyun Chul Kim),석준(Jun Suk) 대한내과학회 1995 대한내과학회지 Vol.48 No.1

N/A Objectives: Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are rare clinical entities characterized by platelet thrombi occluding the microvasculature. These two entities have been linked to similar precipitating factors, leading many to favor the notion that they actually represent different clinical manifestations of same disease that is currently referred to as thrombotic microangiopathy. In the early reports, the mortality from thrombotic microangiopathy was nearly 100%. Since the advent of plasma therapy patient's survival has been improved greatly. Methods: From January 1989 to August 1993, 12 adult patients with thrombotic microangiopathy were evaluated with respect to etiology, clinical and laboratory data at the time of admission and response to therapy. Results: They ranged in age from 22 to 59 years old (mean age 36.3 years) with female preponderance (Female: male=5: 1) In three patients, thrombotic microangiopahy was associated diarrhea, whereas in nine, it was associated with another disease (2 with lupus erythematosus, 2 with cancer, 2 with cyclosporine A, each 1 with pregnancy, poststreptococcal glomerulonephritis and mitomycin). Five cases had prodromal illness characterized by abdominal pain or bloody diarrhea, six had seizure. Mean laboratory values at presentation were follows, Hb 5.7 g/dl, PLT 48,750/mm³, WBC 20,728/mm³, RUN 117 mg/dl, creatinine 7.8 mg/dl, bilirubin 3.2 mg/dl, AST 447.0 U/L, ALT 338.0 U/L, LDH 670.5 U/L, uric acid 10.9 mg/dl, all cases had proteinuria and eight cases with microscopic hematuria. Eight (67%) patients were treated with plasma manipulation, i.e, plasma infusion, plasma pheresis, or both; seven (58%) patients received blood transfusions in forms of whole blood or packed red cells because of severe anemia, Other forms of treatment were steroids (9 patients) and intravenous infusion of r-globulin (2 patients). Eight (67%) patients required hemodialysis during the acute phase of the disease. Of the 12 patients, six (50%) had recovered a normal renal function, one had persistant renal failure. Five (42%) patients died due to either underlying disease or CNS insufficiency. Conclusion: Early diagnosis and introduction of plasmapheresis and plasma infusion seems to increase the survival rate.

An Investigation of the nominal rating current for breakers in distribution system due to the increased capacity of power transformer

조성수(Seong-Soo Cho),한상옥(Sang-Ok Han) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.7(초록집)

극박 방향성 규소강판과 상용 방향성 규소강판의 철손특성 비교

조성수(Seong-Soo Cho),김상범(Sang-Beom Kim),소준영(Joon-Young Soh),채우규,한상옥(Sang-Ok Han) 대한전기학회 2009 대한전기학회 학술대회 논문집 Vol.2009 No.7

Thin-gauged 3% Si-Fe sheets having a high magnetic induction of over 1.9 T have been developed for the purpose of applications where operation frequency is higher than power frequency. In order to clarify requirements of iron loss characteristics for the applications, iron loss characteristics of the newly developed strip were investigated by iron loss separation method and were compared with those of commercially produced 0.3 ㎜-thick electrical sheets. In case of relatively high excitation induction(1.7 T) and low frequency(60 ㎐), reducing hysteresis loss is effective to decrease total iron loss. In case of relatively low excitation induction(1.0 T) and high frequency(1 ㎑), reducing eddy-current loss is effective by decreasing thickness and grain size to improve total iron loss.

주변압기 용량증설에 따른 배전계통의 차단기 정격차단전류 검토

조성수(Seong-Soo Cho),한상옥(Sang-Ok Han) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.7

성인 미세변화형 신증후군의 치료에서 Cyclosporine 의 효과

조성수(Seong Soo Cho),이준호(Jun Ho Lee),이수형(Soo Hyeong Lee),박성배(Sung Bae Park),김현철(Hyun Chul Kim) 대한내과학회 1994 대한내과학회지 Vol.46 No.3

N/A We studied the effects of cyclosporine in 18, steroid dependent or relapsing patients with adult minimal change nephrotic syndrome. The 5 mg/kg/day of cyclosporine was given two divided oral doses with or without prednisolone and mean duration of cyclosporine administration was 7.1 months. Cyclosporine induced complete remission in 13 patients, partial remission in 2 patients and failed in 3 patients, namely overall response rate was 83.3%. There was no correlation between the previous response to steroid therapy and efficacy of cyclosporine. Urinary excretion of protein decreased significantly at 1 months of treatment (p<0.05). There was no significant changes in blood pressure and blood chemistry including BUN, creatinine, potassium, magnesium and uric acid during cyclosporine treatment. Tolerance to the treatment was excellent. Minor side effect such as tremor, hypertrichosis, hypertension and GI trouble were reported in small number of patients, but these were not serious enough to interrupt the study. Relapse occurred in seven out of 8 patient (87.5%) within a mean duration of 4.3±4.0 weeks after withdrawal of cyclosporine. In conclusion, cyclosporine may be a good alternative to steroid in the treatment of minimal change nephrotic syndrome, particulary in steroid dependent and frequent relapser. However prolonged administration of cyclosporine is needed to achieve continued remission because of high incidence of relaspses on withdrawal of cyclosporine.

고자속밀도와 저손실 특성을 갖는 중주파수대 철심재료 개발 및 응용

조성수(Seong-Soo Cho),한상옥(Sang-Ok Han) 대한전기학회 2009 전기학회논문지 P Vol.58 No.2

Thin-gauged 3% silicon steel sheets having a highly grain-oriented texture have been developed as a core material for applications of middle-frequency (400 ㎐ ~ 10 ㎑) devices. The newly developed sheets with a tension coating showed an excellent reduction in iron loss at 400 ㎐ (iron loss at 1.0 T and 400 ㎐ = 4.677 W/kg, iron loss at 1.5 T and 400 ㎐ = 9.742 W/kg) due to high magnetic induction, B10(measured induction at 1000 A/m), of over 1.9 T. In cases of frequencies below 400 ㎐, magnetic induction, B10, of the sample plays a major role to reduce its iron loss as excitation induction increases, whereas, in case of frequency of 1 ㎑, thickness dependence becomes dominant due to a lower iron loss at relatively thinner sample. The sheets with a high magnetic induction, therefore, are favorable for high excitation induction (over 1.0 T) and low excitation frequency (below 400 ㎐) applications, whereas the sheets that can reduce eddy current loss by reducing thickness or domain wall width are advantageous for low excitation induction (below 1.0 T) and high excitation frequency (around 1 ㎑) applications.

극박 규소강판의 장력코팅 효과 및 주파수 특성 비교

조성수(Seong-Soo Cho),송일근(Il-Keun Song) 대한전기학회 2009 대한전기학회 학술대회 논문집 Vol.2009 No.11

Thin-gauged 3% Si-Fe sheets having a high magnetic induction of over 1.9 T have been developed for the purpose of applications where operation frequency is higher than power frequency. In order to additionally reduce iron loss, tension coating without forsterite base coating was applied on surfaces of the thin grain-oriented sheets. Reduction in total loss due to the tension coating results from combination of hysteresis loss and anomalous loss, but the latter plays a major role in the loss reduction. In case of relatively high excitation induction(1.7 T) and low frequency(60 ㎐), reducing hysteresis loss is effective to decrease total iron loss. In case of relatively low excitation induction(1.0 T) and high frequency(1 ㎑), reducing eddy-current loss is effective by decreasing thickness and grain size to improve total iron loss.