• 대한산업공학회지
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• 제6권1호
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• pp.23-26
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• 1980

When the number of stockable item types is too large in certain large scale inventory operations, it is important to classify and screen out the items that need not be stocked; and for the low demand or high cost items, it may be preferable to use one-for-one-ordering policy. In this paper, the problem is formulated in somewhat easier terms, and a criterion is developed that can be used in deciding what items not to stock.

• 품질경영학회지
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• 제21권1호
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• pp.11-21
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• 1993

In this paper, we survey the current status of measurement labor in Korean Industry. At the same time we try to predit the demand and supply of measurement labor to suggest policy measures for equilibrium in measurement labor market. We use a general production function for the prediction which include a set of general homethetic production function.

• 가정과삶의질연구
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• 제27권3호
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• pp.79-91
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• 2009

The purpose of this study is to understand the reduction of energy consumption and demand level for education relating to the reduction of energy consumption by middle school students. First, the perception of the reduction of energy consumption had a significant relationship with sex and grade. Second, the demand level for education relating to the reduction of energy consumption showed a significant relationship with only sex. Third, regression analysis on the influence of perception of the reduction of energy consumption showed a correlation between theperception of a reduction of energy consumption and the demand level for education relating to a reduction of energy consumption. The research suggests that students want an education that reduces energy consumption at school implemented during experience-centered and activity-centered discretionary activities, rather than duringtheory-centered curricular activities. It also suggests that overcoming limitations of space, that is, implementation of such education at various places besides school, and the application of teaching and teaming methods which use the internet and image media are more effective for education for the reduction of energy consumption.

• 한국산업정보학회논문지
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• 제4권4호
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• pp.32-39
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• 1999

주문형 비디오 시스템에서 가변 비트율로 압축된 데이타들은 압축 대상이 되는 데이타의 내용 변화와 압축 기법의 특성으로 인해 단위 시간 당 처리해야 할 데이타 크기가 일정하지 않다. 그러나, 대부분의 주문형 비디오 서버들은 가변 비트율로 압축된 데이타를 실시간에 처리하기 위해 가변 데이타 크기의 최대값으로 시스템 자원을 예약하기 때문에 자원의 활용률이 떨어진다. 본 논문에서는 주문형 비디오 서버에서 시스템 자원의 활용률을 향상시켜 더 많은 사용자를 수용할 수 있는 버퍼 관리 기법을 제안한다. 제안된 버퍼 관리 기법은 데이타에 대한 캐슁 기법과 함께 가변 비트율로 압축된 데이타를 예약할 때 선반입 기법을 적용함으로써 비디오 데이타의 가변성을 줄이고 디스크 대역폭과 서버 버퍼에 대한 활용률을 극대화하였다. 본 논문에서 제안한 버퍼 관리 기법의 효율성은 모의 실험을 통해 확인하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권2호
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• pp.62-70
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• 2012

Rainfall, on Jeju Island varies regionally in relation to Mt. Halla with higher rainfall within southern area and lower in western area, and its variability is expected to expand according to the climate change scenario. Non-parametric trend analysis for rainfall, using both historic (1971-2010) and simulated (2011-2100) data assuming the A1B emissions scenario, shows regionally increasing trends with time. In perspective of agricultural land use, area for market garden including various crop types with high water demand is increasing over the Island, especially in the western area with lower rainfall compared to southern area. On the other hand, area for fruit including mandarin and kiwi with low water demand is widely distributed over southern and northern part having higher rainfall. These regional disparity of water demand/supply may be more affected by extreme events such as drought and heavy rainfall that has not yet been considered. Therefore, it is necessary to make policies for water resource management considering both demand and supply in different regions with climate change impacts over Jeju Island.

• 한국초등과학교육학회지:초등과학교육
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• 제37권3호
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• pp.285-295
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• 2018

The purpose of this study is comparing cognitive development of elementary $4^{th}$ graders and cognitive demand of activities in lesson 'The mirror and the shadow.' Also, the researchers tried to reveal how cognitive development of elementary $4^{th}$ graders and cognitive demand of textbook activities affects the achievement of students. To study students' cognitive development, the researchers use GALT(Group Assessment of Logical Thinking). Piaget's scientific thinking is used to evaluate cognitive demand of textbook activities. With several experts in science education the researchers discussed which scientific thinking is contained in each activities. The results were followed as : (1) The third of activities are significantly affected by students' cognitive development. (2) The another third of activities are influenced by not only students' cognitive development but also other factors experimental instrument. (3) The environmental factors had meaningful impact on the other third of activities.

• 전기학회논문지
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• 제60권6호
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• pp.1091-1096
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• 2011

Currently, the concern about the environment is the issue all over the world, and in particular, carbon emissions of the power plants will not be able to disregard from the respect of generation cost. This paper proposes DR (demand response) as a method of reducing carbon emissions and therefore, carbon emissions cost. There are a number of studies considering DR, and in this paper, the effect of DR is focused on the side of carbon emission reduction effect considering Time-Of-Use (TOU) program, which is one of the most important economic methods in DSM. Demand-price elasticity matrix is used in this paper to model and analyze DR effect. Carbon emissions is calculated by using the carbon emission coefficient provided by IPCC (Intergovernmental Panel on Climate Change), and generator's input-output characteristic coefficients are also used to estimate carbon emission cost as well as the amount of carbon emissions. Case study is conducted on the RBTS IEEE with six buses. For the TOU program, it is assumed that parameters of time period partition consist of three time periods (peak, flat, off-peak time period).

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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• pp.1116-1123
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• 2006

The methodological framework proposed in this paper addresses the strength of the applied Bass model by Mahajan and Muller(1996) that it reflects the substitution of next generations among products. Also this paper is to estimate and analyze the forecast of demand for products that do not exist in the marketplace. We forecast the sales of digital TV using estimated market share and data obtained by the face to face Interview. In this research, we use two methods to analyze the demand for Digital TV that are the forecasting the Demand for the Substitution and binary logit analysis. The logit analysis is to estimate the decisive factor of purchasing digital TV. The decisive factors are composed of purchasing plan, region, gender, TV price, contents, coverage, income, age, and TV program. We apply the model to South Korea's market for digital TV. The results show that (1) Income, region and TV price play a prominent part which is the decisive factor of purchasing digital TV. (2) We forecaste the demand of digital TV that will be demanded about 18 millions TVs in 2015

• Structural Engineering and Mechanics
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• 제58권2호
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• pp.327-345
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• 2016

Many experimental and analytical studies have been conducted with beam-column subassemblages composed of a two-span beam to investigate the progressive collapse resistance of RC frames. Most study results reveal a strength-decreased transition phase in the nonlinear static load-deflection curve, which may induce dynamic snap-through response and increase the chord rotation demand for effective catenary action (ECA). In this study, the nonlinear static response is idealized as a piecewise linear curve and analytical pseudo-static response is derived for each linearized region to investigate the rotation demands for the ECA of the two-span RC beams. With analytical parameters determined from several published test results, numerical analysis results indicate that the rotation demand of 0.20 rad recommended in the design guidelines does not always guarantee the ECA. A higher rotation demand may be induced for the two-span beams designed with smaller span-to-depth ratios and it is better to use their peak arch resistance (PAR) as the collapse strength. A tensile reinforcement ratio not greater than 1.0% and a span-to-depth ratio not less than 7.0 are suggested for the two-span RC beams bridging the removed column if the ECA is expected for the collapse resistance. Also, complementary pseudo-static analysis is advised to verify the ECA under realistic dynamic column loss even though the static PAR is recovered in the nonlinear static response. A practical empirical formula is provided to estimate an approximate rotation demand for the ECA.

• 제어로봇시스템학회논문지
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• 제12권7호
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• pp.631-636
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• 2006

In this paper, an algorithm of time series function forecasting using GMDH(group method of data handling) algorithm that gives more weight to the recent data is proposed. Traditional methods of GMDH forecasting gives same weights to the old and recent data, but by the point of view that the recent data is more important than the old data to forecast the future, an algorithm that makes the recent data contribute more to training is proposed for more accurate forecasting. The average error rate of electric power demand forecasting by the traditional GMDH algorithm which does not use data weighting algorithm is 0.9862 %, but as the result of applying the data weighting GMDH algorithm proposed in this paper to electric power forecasting demand the average error rate by the algorithm which uses data weighting algorithm and chooses the best data weighting rate is 0.688 %. Accordingly in forecasting the electric power demand by GMDH the proposed method can acquire the reduced error rate of 30.2 % compared to the traditional method.