• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.19-25
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• 2008

Nihombashi district, which is located in a heart of Tokyo Metropolitan area, has been flourished as a Japanese economic and cultural center since Tokyo was developed as a capital. Nihombashi district has still remained the Edo idea of stylishness since the government of Edo was established in 1603. During Edo period, population of Edo (former name of Tokyo) reached one million. Edo became one of big city around the world. Nihombashi district has been transformed as economical, financial and cultural center, along with modern transformation of Tokyo. During high economic growth (1955-1975), Nihombashi Bridge and River, which used to a symbol of Tokyo, have been covered with elevated highways. The river was polluted whereas the river does not have any relationship with people's daily activities. Since Japan has focused on environment concern in 80's, people and companies in Nihombashi district and Nihombashi River also requested to restore Nihombashi district and Nihombashi River. There are a lot of projects going on related to regenerate the river and the community, such as to remove highways covered with the river, restore river environment and run water navigation. This article mentioned to introduce the project of Nihombashi River and Nihombashi district that regenerate the community to capitalize history and geographic characteristics in Nihombashi district, to run water navigation through the river, and to review outcomes through various projects.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.151-151
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• 2021

The alarming climate change impacts are demanding the use of renewable energy sources like never before. Hydropower is one of the most cost-effective and environmental friendly energy technology recognized in the world. Big hydropower projects come up with the requirements of huge investment costs along with environmental impacts, whereas small hydropower(SHP) are considered a best solution for the economical source of energy. SHP, basically Run-of-River (RoR) type plants can be sustainable renewable energy sources and given the nature of perennial rivers flowing from steep gradient and rugged topography, feasibility of such plants is equally high in Nepal. The objective of this study is to determine the primary potential sites for the development of RoR type SHP sites using Geo-spatial Information System(GSIS). The use of GSIS enables precise survey of large area within a short period of time. This study has focused on the determination of locations by establishing defined criterions and methodologies and hence have located multiple locations rather than selecting one best location. The approach is applicable for the rapid initial screening of potential locations and results can facilitate detail feasibility study for the technical and economic analysis of SHP in the basin.

• 대한기계학회논문집A
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• 제34권2호
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• pp.237-243
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• 2010

본 논문은 자동차 변속기의 헬리컬기어 검사 장치에 대한 것이다. 기어 프로파일 전용 검사설비는 시간이 많이 소요되므로 생산라인용으로 적합하지 못하다. 본 논문에서 사용된 마스트기어를 이용하여 생산된 기어와 비교하여 방법은 보다 경제적이며 효율적이다. 본 논문에 사용된 3가지 기어검사 파라미터는 nick, 흔들림(run-out) 및 PCD (pitch circle diameter) 등이다. 기어검사장치의 측정정밀도에 영향을 미치는 요소들에 대해서도 또한 언급되었다. 이 장치는 현재 국내에서 전량 수입되는 기어 생산라인용 설비에 실제적으로 사용될 것이다.

• 품질경영학회지
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• 제31권2호
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• pp.117-130
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• 2003

This paper investigates the economic design of synthetic control charts. The synthetic control chart has been proven to be statistically superior to the $\bar{X}$-control chart, but its economic characteristics have not been known. We develop an economic model of the synthetic control chart, based on Duncan's model. The synthetic chart has one more decision variable, the lower control limit for the conforming run length. In addition to this, the significance level and the power of the synthetic chart are more complicated than those of the $\bar{X}$-chart. These features make the optimization problem more difficult. We propose an optimization algorithm by adapting the congruent gradient algorithm. We compare the optimal cost of the synthetic chart with that of (equation omitted)-control chart, under the same input parameter set of Duncan’s. For all cases investigated, the synthetic chart shows superior to the $\bar{X}$-chart. The synthetic control chart is easy to implement, and it has better characteristics than the $\bar{X}$-chart in economical sense as well as in statistical sense, so it will be a good alternative to the traditional control charts.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.38-39
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• 2006

KEPCO is executing a project in Cambodia consisting of two components, "Power Development Master Plan and Institutional Strengthening" and "Greater Mekong Sub-region (GMS) Power Project Preparation" upon request by the government of the Ministry of Industry, Mines and Energy of Cambodia, contracted on $29^{th}$ September 2005. This paper includes a basic design and review of economical efficiency for constructing the two (2) cross border 115 kV transmission lines, which run from the border of Vietnam and Laos to Cambodia, and four (4) 115kV substations. The main contents of the paper include the process of design and results of a review of line route selection, tower and hardware design regarding transmission line design, as well as the type of substation, and arrangement and specifications of equipment with expects to substation design. Also, long-term demand forecasting, and an economic analysis of the project area are included.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.99-101
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• 2006

As the same concept with GIB, GIL(Gas Insulated Line) has been established and run for the first time in New Jersey, America, in 1972. At the beginning, the installation condition of GIL was complicated and the construction cost was excessive, so it was not economical, but the construction cost was substantially reduced with the use of insulation material which is the mixture of $SF_6$ and $N_2$ Gas in Germany, in 1990s. And also comparing to cable, GIL has lots of advantages, such as being capable of the high voltage transmission, being applied to reclosing and lowering the strength of electromagnetic force, Due to these advantages, GIL is recently accepted in many countries.

• 한국환경과학회지
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• 제15권10호
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• pp.967-973
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• 2006

In this study used tank model and specific discharge to calculate low-flow of mountain basin and supply data that need in water resources plan. Low-flow is calculated byspecific discharge and area ratio method as resulted that calculate storage of low-flow by tank model was construed that showd all similar aspect. In judged to help in water resources plan establishment calculating low-flow using model to supplement uncertainty of observed data in that calculate of low-flow ungaged mountain area. It shows by economical and realistic plan until 12 years after development that run parallel and use economic performance analysis result valley flow and groundwater. But wide area water services and Chungju dam since 12 years onward was expose that is economic.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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• pp.203-206
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• 2005

Recently, it is not to much to say that the world of hospital architecture in Korea is in a time of transition that undergo big changes. Each hospital pursues their transformation not only for patiences' changing demands on medical services but to cope with rapid environmental changes that pouring like boundless competition, opening tendency and to get an advantage of competition to attract patiences with other hospitals. It is because national expectations and standards on medical services have risen and they are not satisfied with hospitals that run for doctors and medical care that served technically any more. With rising interests in health, it is emphasized not the functions of hospitals to prevent diseases but the purpose of treatment and securing other facilities according to rising economical incomes except medical facilities.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 제10회 하계 Workshop
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• pp.1-12
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• 2002

Desalination by reverse osmosis (RO), which first entered commercial use in the 1970s, was initially mainly used for treating brackish water. Technological progress led to the development of an RO membrane enabling single-pass seawater desalination. Toyobo succeeded in developing a single-pass seawater desalination RO module composed of hollow fiber type membranes made of cellulose triacetate in 1978, and then in 1979 began production of the first commercially available double-element module. This double-element module has many advantages suitable for seawater desalination. It has high chlorine tolerance and high salt rejection, derived from the properties of the membrane material, and it is highly resistant to fouling and scaling matters due to the unique flow pattern and fiber bundle configuration. These advantages help to explain why the Toyobo double-element module has been used so successfully at the many seawater desalination plants around the world. Since the 1980s, large plants capable of desalinating several tens of thousands of cubic meters a day have sprung up around the Mediterranean and In the Middle East. The Jeddah RO Phase I Plant, which has a capacity of 56, 800m$^3$/day, went into operation in 1989. In 1994, the same sized Phase II Plant came on stream, giving the plant a huge total capacity of 113, 600m$^3$/day. The plant constructor Mitsubishi Heavy Industries, Ltd. (MHI), and the RO membrane manufacturer Toyobo Co., Ltd. In 1998, the world's largest RO seawater desalination plant in operation, which has a capacity of 128, 000m$^3$/day and is run by Saudi Arabia's Saline Water Conversion Corporation (SWCC), went into operation at Yanbu. RO seawater desalination technology has thus already reached the stage of full-scale commercial use. In order to encourage its wider use, however, RO desalination needs to be made more economical by lowering construction and water treatment costs. Toyobo has therefore developed a new economical RO desalination system by a recovery ratio of 60% using a high-pressure module with a high product flow rate. In 2000, Toyobo high recovery membrane module was selected for the largest seawater desalination plant in Japan, which has a capacity of 50, 000m$^3$/day.

• Journal of Animal Science and Technology
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• 제48권2호
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• pp.315-324
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• 2006

This research was conducted to clarify the characteristics of electrochemical decolorization of effluent discharged from a biological animal wastewater treatment process and to finally establish parameters or mode for optimum operation of electrolysis system. Average color unit of wastewater was about 1,200 and DSA(Dimensionally Stable Anode) was used as electrode. Experiments were performed with two different operation conditions or modes, fixed voltage-free current(Run A) and free voltage-fixed current(Run B). Color removal rate was proportional to the electrode area and electrical conductivity, and an equation subject to them at a condition of fixed voltage was derived as follows; Ct=C0ekt, k=[{0.0121×ａ(dm2)× c(mS/cm)}+0.0288], [where, C0: initial color, Ct: color unit after treatment for t, k: reaction coefficient, t: time(min.), ａ: electrode area, c: conductivity]. From the study on the effects of current density on color removal, it was revealed that the removal efficiency of color was function of the current density, showing direct proportion. However, when considered energy consumption rate, maintenance of low current density was an economical way. Based on the obtained results, it was concluded that supplementation of electrolyte is not necessary for the removal of color from the effluent of secondary treatment process and operation with the mode of free voltage-fixed current, rather than operation with fixed voltage-free current mode, would be an efficient way to increase the removal performance and capacity per consumed energy.