• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.758-765
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• 1999

The estimation of reasonable amount of domestic cold water and hot water supplies in apartment houses is very important for the economical design of domestic cold water and hot water supply system which include pumps, boilers, heat exchangers, and various water reservoirs. To suggest the model of predicting reasonable amount of domestic cold water and hot water supplies, residents and actual domestic cold water and hot water consumption have been investigated for 740 apartment houses in Seoul and Bun-Dang, Kyunggi-Do. The model is suggested as a function of exclusive area of the apartment house and results of the model show generally good agreement with published data.

• Journal of Korea Water Resources Association
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• v.40 no.7
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• pp.555-570
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• 2007

The effects of climatic changes owing to urbanization on annual water balance have been studied. In this study, 56 meteorological stations including Seoul metropolis in South Korea have been selected, and the area of study site is $314\;km^2$. The meteorological station is centrally located in the study area with a 10 km radius. Land use status of study area was examined to estimate the urbanization extent, so that annual actual evapotranspiration could be estimated. Annual runoff was estimated by annual water balance approach using the estimated annual actual evapotranspiration and measured annual precipitation. Annual actual evapotranspiration was estimated by applying experimental equation suggested by Zhang et al, (2001) which was evaluated from 250 watersheds all over the world. Study results show that reference evapotranspiration is tending upwards due to urbanization; therefore, it seems that climatic change due to urbanization may increase the amount of annual actual evapotranspiration. However, the increase of residential area due to urbanization in study area may decrease the amount of annual actual evapotranspiration. The study results indicate that urbanization effect on annual trend of precipitation was not significant. In urban area, annual runoff is directly affected by annual precipitation, and compared with annual precipitation, annual variation of actual evapotranspiration was not significant even though it was estimated by using annual precipitation. It seems that the effect of urbanization on annual actual evapotranspiration does not influence on annual runoff significantly, and that urbanization effect on annual runoff Is not significant.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.147-150
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• 2000

Manual and predictive defrosting method is used in current refrigerators, which have several problems in terms of energy consumption and efficiency. fuming the defrosting system on by the amount of frost remains to be an important problem which has to be improved by refrigerator manufacturers. The sensing of the amount of frost by FDS(Frost Detecting Sensor) and its proper mounting point are investigated in the paper. Also the realization of actual defrosting system through experiments of operation, energy consumption and sensing mechanism is presented.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.57-64
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• 2009

This study has analysed actual overbreak, shotcrete rebound and the ratio between the actual quantity of shotcrete to designed shotcrete measured during a NATM tunnel construction. The measured shotcrete rebound was about 7.2% in average which was about half the allowable rebound (15%), showing shotcrete spraying was performed well. Based on the measurement of excavated tunnel shape, average overbreak was about 28.5cm after tunnel excavation by drill and blasting method. This was about 260% of allowable overbreak. In addition, due to the rebound and overbreak actual amount of shotcrete used in the tunnelling work was about 116.5 % of the designed value. According to the field measurement the ratio of actual shotcrete to designed value showed some relation with standard support pattern, but the size of overbreak did not show the correlation with standard support pattern. Hence current design specifications stating the size of overbreak based entirely on standard support pattern should perhaps be reestablished. The insight into the design guideline regarding overbreak and shotcrete.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.227-231
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• 2015

The focus of this study is on the accuracy in quantity estimates made by BIM for materials needed during construction. BIM-Revit Architecture 2014 is utilized to establish the information for an actual case to conduct estimates for the amount of reinforced concrete and formwork needed. The actual case is with a total construction area of 5,438 square meters and a total floor area of 31,623 square meters. The building commenced in December 2012 and the major structure has been completed in 2014. It is a RC structure with 4 stories underground, 12 stories above and 3 roof floors. The result shows that both of the quantity estimates of reinforced concrete and formwork are higher than that of actual use in the case. The estimate of reinforced concrete is higher than that of actual use by 2.18%, while the estimate of formwork is higher than that of the actual use by 13.04%. The results indicate that the estimate of reinforced concrete made by BIM has high accuracy, but the accuracy of the formwork estimate still needs improvement.

• Transactions of Materials Processing
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• v.8 no.2
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• pp.208-215
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• 1999

To increase rolling yields by minimizing trimming losses of hot-rolled plate, optimization logic for the edger model has been developed. The logic to determine optimum edging amount model has been formulated on the basis of actual production rolling data. In case of broadside rolling, the fish tail shape at the sides of plate was better for reducing the crop loss and this could be achieved when the edging amount of broadside rolling was increased. At a given broadside rolling ratio, methodology to determine optimum edging amount for the finish rolling which could minimize the width deviation of plate were systematically derived. Therefore, for a given broadside rolling condition and the permissible tolerance in width deviation of plate, it was possible to optimize the edging amount in finish rolling to maximize rolling yields. The application of optimization logic in this study increased rolling yields from approximately 10% to 30% at various longitudinal eding raitos.

• International Journal of Highway Engineering
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• v.19 no.4
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• pp.9-18
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• 2017

PURPOSES : This study evaluates the reasonableness of the recommended amount of deicing chemicals based on historical data for snow removal. The result can be used to aid decision-making for the reservation of cost-effective de-icing chemicals. METHODS : First, the recommended amount of de-icing chemical to use and historical usage data were evaluated to identify specific usage characteristics for each region. Road maintenance length and snow-removal working days were analyzed over the past five winter seasons. Next, differences in the recommended amount of chemical to use and actual use were compared using the Kolmogorov-Smirnov test. Last, the two types of data were analyzed using a chi-square test to verify if the two distributions of variation pattern are statistically significant. We found that there are significant differences between the data from each region during the past five winter seasons. RESULTS : The results showed that the equation for calculating the amount of de-icing chemical to use appears to be revised. CONCLUSIONS : The results imply that the equation for calculating the amount of de-icing chemical to apply as a national standard is very important when the public agency makes decisions related to snow-removal.

• KIEAE Journal
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• v.13 no.1
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• pp.9-15
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• 2013

This study aims to analyze, by forming an experimental area of artificial soil green area that is of equal scale and analyzing the characteristics of runoff water in accordance with the cross-section configuration, applied the benefits in an actual multi-housing case study complex. In examining the measurement test results of the runoff water infiltration amount and surface runoff amount of a low-profile type green area(Dish type) and a general type green area(Mound type), Dish type was seen to have 1.5-times higher runoff water infiltration amount than Mound type during heavy rainfalls and showed about a 50% reduction with respect to the surface runoff amount. In other words, artificial soil green area offers the benefit of reduction of surface runoff amount and suggests, in actuality even with a change to the cross-sectional configuration of artificial soil green area alone at the time of construction of multi-housings, the possibility of benefits and reduction of costs spent on existing rainwater management facilities.

• Proceedings of the Society of Korea Industrial and System Engineering Conference
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• 2002.05a
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• pp.163-170
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• 2002

In the form of B2C transaction, making an on-line order by using the website increases rapidly. An off-line order at the whole sale outlets is geometrically increasing. However, it is so true that both types of market are showing a tendency to become computerization. As to apply this type of computerized B2B transaction to this kind of large scale wholesale outlets, the most important fact to be considered is that there must have no data error. In addition to this, an accurate counting of actual stock is a precondition to decide a suitable amount of production and a timely delivery of goods. In this study, reducing elements of the risk that may create a difference In between actual stock and that in the computer, the integrated B2B ordering system is designed by taking actual cases an example in order to manage the information for a sale, which is conducted by various system in the large scale wholesale outlets such as E-mart, Carefour or the same kinds.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1165-1172
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• 2008

A considerable amount of research has focused on the dimensionality of service quality construct. To achieve and maintain their comprehensiveness and profitability, restaurant managers should manage and aim to continuously improve the level of service quality offered to their customers. This paper is focused on service quality in the Korean native cattle and imported beef restaurant industry in the Korea. So, this paper has adapted DINESERV scale so that restaurant managers can use it to determine how customers perceive the service quality in Korean native cattle beef restaurant and imported beef restaurant. The purpose of this research is to test the difference in importance and actual performance of 5 dimensions between the restaurants that sell the beef of Korean native cattle and imported cattle. The t-value is used to test difference of the importance and actual performance for DINESERV's 5 dimensions of the 2 restaurant types. But, there is no difference between Korean native cattle and imported beef restaurant.