• The KSFM Journal of Fluid Machinery
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• v.13 no.4
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• pp.11-17
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• 2010

The developed control valves, installed on the hot water distribution manifolds for the floor heating system, consist of the balancing valves and the shut-off valves. The balancing valve was designed to improve the flow control performance and to reduce the noise emitted from the valve by modification of the general V port. The port of the shut-off valve was designed with two ceramic plates, working by rotating upper plate, to improve the duration and to reduce the noise. For the evaluation of the new valves, the flow rate was measured and noise level test was carried out. The test results showed that the error of the flow rate accuracy test for the flow balance of each manifold circuit was less than ${\pm}3%$ and the noise level was less than 35 dB(A).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4381-4387
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• 2015

Ship hull is a compound curved shape and most of shipyards have been using gas heating method for the surface forming of steel plate. This traditional forming process have problems such as difficulties in heat input control and poor working conditions due to loud noise and air contamination. Recently, researches on automatic hull forming system have been conducted using high frequency induction heating method which have good control ability and favorable working environment. In this study, the induction heating simulation system for curved surface forming of steel plate was developed and induction heating experiments were performed. Based on the results of this study, efficient induction heating coil design and optimal heating conditions for the automatic hull forming system can be obtained.

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.28-28
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• 2004

• Journal of the Korean Society of Tobacco Science
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• v.30 no.2
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• pp.94-102
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• 2008

In this paper, we describe our study on the characterization of tobacco leaves by their pyrolysis patterns. Two kinds of tobacco leaves were pyrolyzed and analyzed by Double-Shot Pyrolysis-Gas Chromatography/Mass Spectroscopy (Py-GC/MS) methods. Three grades of Korean flue-cured tobacco leafsuch as B1O, AB3O, CD3L and burley tobacco leaves such as B1T, AB3T, CD3W were pyrolyzed with six discrete but stepwise heating temperature ranges, those are from 100$^{\circ}C$ to 150$^{\circ}C$, 150$^{\circ}C$ to 200$^{\circ}C$, 200$^{\circ}C$ to 250$^{\circ}C$, 250$^{\circ}C$ to 300$^{\circ}C$, 300$^{\circ}C$ to 350$^{\circ}C$ and finally from 350$^{\circ}C$ to 400$^{\circ}C$. Using the resultant 52 pyrolytic components identified in the programs as components, principal component analysis (PCA) showed statistical classification between flue-cured and burley tobacco lamina. Among six pyrolysis temperature ranges, the best discrimination was achieved at the temperature range from 250$^{\circ}C$ to 300$^{\circ}C$ and from 300$^{\circ}C$ to 350$^{\circ}C$.

• KIEAE Journal
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• v.15 no.2
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• pp.103-107
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• 2015

Purpose: Since September 1st, 2013, subjects of the evaluation have been expanded, and the evaluation standard has been detailed to enable Building energy rating system for all buildings. Accordingly, the new evaluation program (ECO2) has been developed, and therefore, apartment applied after September 1st, 2013 were evaluated with the new evaluation program. Therefore, this research suggests the improvement plan to figure out reasons for the evaluation result calculation and to calculate the evaluation results close to the actual energy usage by analyzing and comparing primary energy consumption as a result of the new evaluation program (ECO2) and actual heating energy usage on the same building. Method: When comparing evaluation results of the new evaluation program (ECO2) and actual heating energy usage, the tendency was similar but different. Also when comparing seasonally, the tendency was similar, but the different between actual heating energy usage and primary energy consumption during winter is greater than during spring or fall, and when comparing seasonal electric usage, heating alternatives were used through increased electrical usage during winter compared to during spring or fall. Result: Therefore, when evaluating apartment with the new program (ECO2) in the future, evaluation items relevant to the use of heating alternatives should be added, and the modification factor should be added according to the region. Based on the evaluation results of the research and actual energy usage, the Modification factors of the central part and the southern part were calculated respectively as 0.5 and 0.8.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.7
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• pp.392-397
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• 2013

To fulfill the demands concerning energy efficiency for zero energy buildings, various technologies of architects and engineers are required. This study aims to estimate the thermal performance of heat source equipment in which part load characteristics are considered in an office building. Overestimation of heat source equipment was reviewed through literature survey, and heating and cooling loads depending on the capacity and division of the equipment were analyzed through a simulation program (DOE-2.1E). The conclusions gained from this study are as follows; 1) The more the division of equipment, the less the heating and cooling energy consumption. 2) When a large item of equipment is divided into two small items of equipment, the optimum application rate showed as 5:5 for chiller, and 7:3 for boiler, respectively.

• Journal of the Korean housing association
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• v.15 no.1
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• pp.51-62
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• 2004

Koreans had started moving to Yunhaju in Russia for escaping from the tyrannical rule and famine in 1860's in Korea. It had been veiled and nearly known about Korean's life there because of social and political situation of Russia until the Perestroyka. This study examined the dwellings of Korean Diaspora in Yunhaju through visiting their houses and having an interview. Results of research were as following: 1) Russian traditional houses which Koreans built was followed by Russian style basically and Koreans used the space slightly different way. Korean Diaspora have been adopted Russian life style with keeping their own traditional way of living. 2) Some Korean Diaspora still have been kept traditional heating system 'Ondol' in their houses until now in Yunhaju. Moreover over, it is known that people of Central Asia prefer to set 'Ondol' recently as a very specific and expensive heating system. 3) Korean's food style in Yunhaju is the one mixed with Russian, Korean, and Central Asian foods. This study could be a first step to supply for a basic information for studying of Korean Diaspora in Russia and it is needed to take more deep research in other areas in Russia.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.1
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• pp.81-88
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• 2005

There have been many studies on generation equipment and plant piping, but there is no significant study result on the heat transportation pipe. As such, this study established basic theory on the compensated method among buried pipe for regional heating, and further obtained the following results by applying the conditions of AGFW and NCHPP respectively in calculation of friction and maximum installation distance for the buried pipe. Friction coefficient according to the types and physical properties of soil, friction and maximum installation distance were compared to set the application value of friction coefficient according to the location of works. Calculation formula of clay load to be applied for calculation of friction was introduced to the formula of AGFW and the formula of NCHPP that has been used in Nowon district since 1997 to determine the difference and applicability. $120^{\circ}C$ and $95^{\circ}C$ were applied in temperature difference for expansion volume to compare the arm length at the curve pipe so thai it can be reflected in the design in the future. Maximum installation distance according to thickness of pipe was compared to present the necessity of unified specification so that same kinds of pipe materials can be used for same kinds of works.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.206-210
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• 2012

Ground source heat pump is a central heating and cooling system that pumps heat to or from the ground. Building Integrated Geothermal system used in this experiment is one of the Ground Source Heat Pump Systems which utilize energy pile. The purpose of this study is to evaluate heating performance of the system. The building is a low-energy experiment apartment in Yonsei University Songdo Campus and the subject is one of the energy reduced houses in this apartment. In the experiment, indoor temperature, outdoor temperature and the inlet and outlet temperature of ground heat exchanger and subject model, were measured. Then the heat pump's Coefficient of performance(COP) of the heat pump was calculated. As a result, the COP of heat pump is 4-5. Although the depth of the ground heat exchanger in this experiment is shallower than usual heat exchanger, the result of heating performance of this system was good as well.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.27-32
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• 2009

The measuring apparatus such as heat meter is legally obliged to be installed and used for heat rating with heat or flow rate in residential buildings in Korea. There are two kinds of apparatus to measure heat consumed at each households, i.e., heat meter and hot water flowmeter. Contrast to the most of buildings with hot water flowmeter well being used for rating, heat meters have been used only 42.6% in the buildings with central heating system. But there is a critical problem in the course of using hot water flowmeter for heat rating, yielding distorted and unfair result which is different from the real value of heat supplied. Experiments with several parameters were carried out in this study to analyze this phenomenon quantively and alternative methods were proposed for rational heat rating.