• Magazine of the Korean Society of Agricultural Engineers
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• 제48권2호
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• pp.15-23
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• 2006

우리나라의 수량과 수질의 관리를 위해서는 상류와 하류의 유출 상황을 파악하는 것이 가장 중요하다. 어느 임의 지점의 유출량은 생활용수, 공업용수, 농업용수 등 유역 상류의 각종 용수의 수요가 반영돼 나타난 결과라고 할 수 있다. 이 중에서 농업용수의 변화는 생활용수, 공업용수에 비해 변화폭이 크고 다양하게 나타난다. 그러나 현재 사용되고 있는 대다수의 유출모형은 용수수요를 고려하지 못하고 있는 상태이다. 우리나라의 유역에서 논이 차지하는 비중은 전국토의 11% 정도에 이르며, 논의 저류능력을 고려할 때 농업용수가 유출에 미치는 영향은 매우 크다고 할 수 있다. 따라서 농업용수 수요량을 다양하고 쉽게 추정할 수 있는 프로그램을 개발, 이용하여 농업용수 수요량을 추정하여 유출 모의에 적용함으로써 보다 현상에 적합한 유출량을 생산하는 것이 중요하다. 따라서, 본고에서는 하천 상류와 하류의 유출량 모의를 위해 사용될 농업용수 수요량을 손쉽게 추정할 수 있도록 개발된 WARES(WAter Requirements Estimating System)에 대해 소개하고자 한다.

• Proceedings of the KSR Conference
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.838-843
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• 2006

In our modern society, such electric facilities as lighting, elevators, water supplies, drainages, waste water treatments and landscape lighting are being more enlarged, diversified and technology-intensive owing to outstanding technological development, while they require reliable and safe electricity. On the other hand, as more electric energy is consumed with more complicated systems operated, any accident from a personal electric system is likely to have wider spreading effects. In particular, the electric receivers and transformers installed for such public facilities as subway stations require highest safety, reliability and economy, but such requirements tend to be less considered than such financial requirements as budget conditions, much less their safety and reliability. In such a circumstance, this study was aimed at suggesting some standards for safe, reliable and economic subway electric systems in terms of their scale, location and uses. Specifically, this study put forwards the ways to optimize and standardize the electric systems including receivers and transformers for subway stations in order to make them safer, more reliable and economic.

• Korean Chemical Engineering Research
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• 제55권2호
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• pp.170-179
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• 2017

We investigated design requirements of feed water drain and hydrogen vent systems for the sodium-water reaction pressure relief system (SWRPRS) of the prototype generation IV sodium cooled fast reactor (PGSFR). We evaluated the areas of the gas vent pipe of the water dump tank and the length of the water drain pipe of the steam generator to rapid drain of the water steam inside the steam generator for the normal and refueling operations, respectively. We also calculated the diameter of the gas vent pipe of the sodium dump tank which met its design pressure.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 한국농공학회 2005년도 학술발표논문집
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• pp.679-685
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• 2005

In Korea, water management policy had been successfully conducted until late 1980's. During the period, fundamental needs of human-being, such as requirements of drinking and irrigation waters and flood protection for living, had been satisfied. However, most of recent water problems occurred after the late 1980's such as water quality management and new water resources development, have been unresolved and accumulated. Because, our water governing institutions have become ineffective as water management issue has been changed gradually from fundamental human needs such as water supply and/or flood protection to complex/integrated issues, for example, river restoration. To solve those water problems accumulated, we needs a new paradigm of water governing institution such as setting up national water management committee and river basin committee, in order to coordinate water-related ministries' policies and establish national water resources planning in an integrated format.

• 한국기계연구소 소보
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• 통권15호
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• pp.117-125
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• 1985

It is usual practice to ballast a sip to maintain requires operational safety at sea. However, excessive ballasting may reduce the operational economy of a ship. Therefore, The determination of the optimal location and quantity of ballast water is one of the important works at the preliminary design stage. To provide a convenient tool to ship designers the program for the determination of the optimal location and program the effect of the change of ballast water quantity in each tank on some characteristics of a ship, such as trim, initial stability and heel, is investigated and the minimum quantity of ballast water for each tank which satisfies the operational safety requirements is calculated.

• Magazine of the Korean Society of Agricultural Engineers
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• 제18권3호
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• pp.4195-4205
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• 1976

The purpose of this study is to evaluate the existing methods for calculating or estimating the consumptive use (Evaportranspiration) of any agricutural development project area. In determing the consumptive use water in the project area, there will require the best way for estimating irrigation requirement. Many methods for computing the evaportranspiration have been used, each of them with its merits and demerits at home and abroad. Some of these methods are listed as follows: 1.The Penman's formula 2.The B1aney-Criddle method 3.The Munson P.E. Index method 4.The Atmometer method 5.The Texas Water Rights Commission (TWRC) method 6.The Jensen-Haise method 7.The Christiasen method Therefore, the authors will introduce the more widely used method for calculating Consumptive Use by G.H. Hargreaves. The formula is expressed in the form Ep= K·d·T (1.0-0.01·Hn) Hn=1.0+0.4H+0.005H2. This method was adopted for the first time to determine the Irrigation requirements of Ogseo Comprehensive Agricultual Development project (Benefited area:100,500ha) in Korea. This method is presented in somewhat greater detail than the others. Formula is given for the computation of evaportranspiration (with various levels of data availability) Sampel computation of irrigation requirements for Ogseo irrigation project is included. The results and applied materials are summarized as follows. 1. In calculating the Hargreaves formula, the mean temperature relative, humidity, length of day, and percentage of sunshine from three stations of Iri, Jeonju, and Gunsan were used. 2. Monthly evaporation values were calculated by using the formula. 3. Meteological data from the three stations records for the ten years (1963∼1972) were used. 4. The annual irrigation requirements is 1,186mm per hectare, but the case to consider effective rainfall amount takes the annual irrigation demand being 700mm per hectare.

• Nutrition Research and Practice
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• 제11권4호
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• pp.300-306
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• 2017

BACKGROUND/OBJECTIVES: The doubly labeled water (DLW) method is considered the gold standard for the measurement of total energy expenditure (TEE), which serves to estimate energy requirements. This study evaluated the accuracy of predictive dietary reference intake (DRI) equations for determining the estimated energy requirements (EER) of Korean adults by using the DLW as a reference method. SUBJECTS/METHODS: Seventy-one participants (35 men and 36 women) aged between 20 and 49 years were included in the study. The subjects' EER, calculated by using the DRI equation ($EER_{DRI}$), was compared with their TEE measured by the DLW method ($TEE_{DLW}$). RESULTS: The DRI equations for EER underestimated TEE by -36.3 kcal/day (-1.3%) in men and -104.5 kcal/day (-4.9%) in women. The percentages of accurate predictions among subjects were 77.1% in men and 62.9% in women. There was a strong linear correlation between $EER_{DRI}$ and $TEE_{DLW}$ (r = 0.783, P < 0.001 in men and r = 0.810, P < 0.001 in women). CONCLUSIONS: The present study supports the use of DRI prediction equations to determine EER in Korean adults. More studies are needed to confirm our results and to assess the validity of these equations in other population groups, including children, adolescents, and older adults.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.629-636
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• 2000

In this study, we investigated the characteristics of labor of water management and maintenance, water requirement, water quality(T-N, T-P, COD) in the paddy plot irrigated by pipeline with two types of hydrants: automatic and manual. The automatic hydrant have been introduced to the paddy field to save water and reduce the labor for water management. The automatic hydrant is automatically opened and closed according to the water depth of a paddy plot. The automatic hydrant generally developed more troubles than the manual hydrant. The water requirements are 2.7mm/d for the automatic hydrant plot and 17.6mm/d for the manual hydrant plot. The concentrations of pollutants in the two plots are higher in the ponded water than in the irrigation water and are highest after fertilizer application.

• Journal of Korean Society of Water and Wastewater
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• 제29권2호
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• pp.223-231
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• 2015

District Metered Area (DMA) construction is one of the most cost effective alternatives for management of water loss (i.e., water leakage) and energy consumption (i.e., water pressure) in water distribution systems. Therefore, it's being implemented to numerous new and existing water distribution systems worldwide. However, due to the complexity of water distribution systems, especially large-scale and highly looped systems, it is still very difficult to define the optimal boundary of DMAs considering all the aspects of water distribution system management requirements. In this study, a DMA design methodology (or a DMA design model) was developed with Geographic Information Systems (GIS) and hydraulic distribution system model to determine the optimal DMA boundary.

• Journal of the Society of Naval Architects of Korea
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• 제47권2호
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• pp.258-264
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• 2010

Various kinds of ballast water treatment systems (BWTS) have been developed corresponding to reinforced IMO rules for marine environment. Some of them got the certificate of IMO and others are waiting for it. Selection of optimum BWTS is very important. Optimum BWTS means not only functional requirements but also economic efficiency. This paper presents economic analysis model for optimum BWTS according to ship type and size. In this study 10 kinds of BWTS whose initial installation cost and maintenance cost are known are analyzed based on present worth method. It is assumed that all BWTS satisfy minimum functional requirements and we need to consider different economical efficiency. Through the economic analysis we could select optimum BWTS.