• 한국태양에너지학회 논문집
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• 제36권4호
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• pp.1-9
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• 2016

The purpose of this study was to compare heat shading performance of various blind types in summer. 4 types of blinds were employed and the results are summarized as follows: 1) There were significant differences in indoor thermal environment and heat shading performance between different heat shading devices, and functional blinds demonstrated relatively superior heat shading performance. 2) Indoor long wave radiation influx measures were lowest for the coating roll blind (Blind B), followed by the coating venetian blind (Blind C), the venetian blind (Blind A), the roll blind, and not having any blinds at all. 3) Such examination results carry implications to reduce cooling load and enhance the indoor environment.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.1140-1151
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• 2023

Fully Ceramic Microencapsulated (FCM) fuel is emerging advanced fuel material for the future nuclear reactors. The fuel pellet in the FCM fuel is composed of matrix and a large number of TRistructural-ISOtopic (TRISO) fuel particles which are randomly dispersed in the SiC matrix. The minimum layer thickness in a TRISO fuel particle is on the order of 10^-5 m, and the length of the FCM pellet is on the order of 10^-2 m. Hence, the heat transfer in the FCM pellet is a multi-scale phenomenon. In this study, three multi-scale heat conduction models including the Multi-region Layered (ML) model, Multi-region Non-layered (MN) model and Homogeneous model for FCM pellet were constructed. In the ML model, the random distributed TRISO fuel particles and coating layers are completely built. While the TRISO fuel particles with coating layers are homogenized in the MN model and the whole fuel pellet is taken as the homogenous material in the Homogeneous model. Taking the results by the ML model as the benchmark, the abilities of the MN model and Homogenous model to predict the maximum and average temperature were discussed. It was found that the MN model and the Homogenous model greatly underestimate the temperature of TRISO fuel particles. The reason is mainly that the conventional equivalent thermal conductivity (ETC) models do not take the internal heat source into account and are not suitable for the TRISO fuel particle. Then the improved ETCs considering internal heat source were derived. With the improved ETCs, the MN model is able to capture the peak temperature as well as the average temperature at a wide range of the linear powers (165 W/cm~ 415 W/cm) and the packing fractions (20%-50%). With the improved ETCs, the Homogenous model is better to predict the average temperature at different linear powers and packing fractions, and able to predict the peak temperature at high packing fractions (45%-50%).

• 동의생리병리학회지
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• 제16권4호
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• pp.630-636
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• 2002

After The Yellow Emperor's Canon of Internal Medicine, The text researches of pathologic change to the liver disease concluded the next, 1, The category of liver-disease(肝病) include the Symptoms of abnormality due to vital energy and blood motion, emotion and intention, muscular and reproductive function, and legions around descending liver channel. 2. In the theory that Liver-Yang energy(肝陽氣) is always overproducing, Liver-Yin blood(肝陰血) is always lacking, pathologic characteristics for liver disease is functional change of malfunction of the use of body(體用失調), So nourishing the liver and kidney is used for the principal aspects of a disease. regulating and calm the liver is used for the secondary aspects of a disease as the treatment plan, 3. If malfunctioning of the functions of dispersion and discharge(疏泄), Iiver-energy(肝氣) is becoming degected, So overproduct and overflow of ascent and exhalation of liver-yang(肝陽) is becoming blood are ascending following energy. complete usage of Yin-blood(陰血) is responsible for some kinds of mass formed by blood stasis in the early stage of pathogenesis of liver disease syndrome of the energy system as the progession of disease extravasated blood is forming. the pathologic characteristics is appeared loss of control of the vital energy and blood(體用失調) at the liver disease. 4. Sthenia-syndrome of liver(肝實證) and liver-heat syndrome(肝熱證) is appered that overproducing and overflow of dispersion(疏泄太過) and discharge is responsible for overfunctioning of liver disease or some kinds of heat syndrome such as liver fire(肝火), Sthenia of liver-yang(肝陽上亢), the syndromes of sthenic liver heat(肝實熱) are appered. deficiency of the liver(肝虛證) and cold syndrome of liver(肝寒證) is classified pathologic characteristics of cold and heat, deficiency and excess that regression of sensory, motor, mental due to lack of dispersion and discharge(疏泄不及), or intruding of the cold miasma, are degected. 5. The liver is close relation of physiologic function and internal organ such as spleen, stomach, lung, heart, kidney, gall bladder by the meridian channels, because of property of wind Zang, rapid progession is classified by phthologic charateristics.

• 대한한방내과학회지
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• 제11권1호
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• pp.1-13
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• 1990

We objerved the following results from The Yellow Emperior's Canon of Internal medicine through the investigation of literature about fever. 1. Fever is divieded two type asthenic fever sthenic heat and It accused two type of excess of Yang-exoganous heat, deficiency of Yin-internal fever 2. The cause of fever is divieded three type, exoganous cause, internal cause non-exoganouse and internal cause Among the cause of fever Exoganous cause is almost affected by cold-evil Internal cause is affected by deficiency of Yin and seven emotion caused by having sex after intoxigation or over-exertion, and non-exoganous and internal cause bring about the difference of a personal life and food and drink 3. The sympton produced by fever is appeared differently through-pulse and meridian and they are indication of Diagnosis 4. The theory of treatment about fever are as follows Drinking cold-water Practising acupuncture Trerating hot-evil by cold Dispel cold by warm Treating cold-evil by heat Promote vital energy circulation by cold Treating warm-evil by cold Promating circulation by cold Treating cold-evil by warm Promoting circulation by heat.

• KIEAE Journal
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• 제17권4호
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• pp.41-48
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• 2017

Purpose : Currently, 25% of the domestic energy consumption structure is used as building energy, and more than 18% of this energy is consumed in the residential. Accordingly, various efforts and policies that can save energy of the building is being performed. The various researchers are conducting research to diagnose the thermal performance of existing buildings. This study is to apply in the field of precision thermal insulation performance diagnostic method for thermal performance analysis of existing detached house in Seoul, Gangreung, Gyeongju, Pohang. And this paper is analyzed quantitatively measure the existing detached house energy performance. Method: Research methodology analyzed the thermal performance over the Heat Flow Meter method by applying the measurement process and method by applying the criteria of ISO 9869-1 & ASTR method. In this study, the surface heat transfer coefficient was calibrated by applying indoor surface heat transfer resistance with reference to ISO 6946 standard. The measurement error rate between the HFM diagnosis method and the ASTR diagnosis method was reduced and the measurement reliability was obtained through measurement method error verification. Result : As a result of the study, the thermal performance vulnerable parts of the building were quantitatively analyzed, and presented for methods which can be improved capable of efficient energy use buildings.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.395-401
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• 2008

Since metallic foam will increase the performance of heat exchanger, it have caused many researcher's attention recently. Our research base on the model that metallic foams applied to heat exchanger. In this case, there is three kind of heat transfer mechanisms, heat conduction in fibers, heat transfer by conduction in fluid phase, and internal heat change between solid and fluid phases. In this paper we study both the hydraulic and thermal aspect performance. Pressure drop along air flow direction will be presented. As thermal aspect, we first discuss the acceptance of applying thermal equilibrium among the two phases. then to calculate the dimensionless temperature profile, the heat transfer coefficient and Nu number in 14 metallic foams(7 Aluminium foams, 7 FeCrAlY foams). All these discussion is based on the same velocity u=2 m/s.

• 조명전기설비학회논문지
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• 제26권5호
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• pp.1-12
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• 2012

In order to reduce energy consumption and greenhouse gas emission in building domain, thermal insulation of building is being enhanced. In a well insulated and tightened environment, internal heat gain caused by solar radiation, luminaires, electronic appliances and metabolism can be more important to thermal condition of building. This paper presents mathematical/physical models of quasi-adiabtic room and lighting fixtures using heat balance equation and thermal-electric analogy to quantify and modelize the heat gain due to luminaires. Experimental results are used to identify thermal parameters of theoretical models. And simulation results of models using Matlab/Simulink are conducted to verify the models and to investigate the thermal effect of lighting fixtures into quasi-adiabatic room.

• 한국지열·수열에너지학회논문집
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• 제8권1호
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• pp.13-20
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• 2012

This is an experimental study on the performance characteristics of effective heat pump in the cooling mode using a single-stage compression $CO_2$ cycle with an IHX(internal heat exchanger). The performance of a single-stage compression with IHX was investigated according to charge amount and operating condition. Moreover, the performance characteristic of cooling operating was analyzed with the length of IHX. As a result, the optimum refrigerant charge amount was 2.2 kg. The optimal system COP for compressor frequency of 30, 40, 50, and 60 Hz was 3.493, 3.228, 2.978, and 2.659, respectively. Since the system with IHX can maintain large cooling capacity regardless of operating condition, the system performance doesn't reduce considerably under unfavorable condition. When the compressor frequency was 40 Hz, the COP for a system with IHX length of 3 m and 5 m was 3.361 and 3.51, respectively. By using the IHX into a $CO_2$ cooling system, the performance and reliability improves simultaneously.

• 설비공학논문집
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• 제26권12호
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• pp.565-571
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• 2014

Nowadays, to make buildings light weight and aesthetically pleasing, curtain wall structure are commonly used. Therefore, window to wall ratio is increasing, which has caused cooling and heating load in crease in buildings as well. This phenomenon has negative impact from energy point of view. This paper analyzes window and wall convective heat gain when the slat reflectance of external and internal blinds are changed for the better understanding of the fundamentals behind the phenomena. It was observed that, if slat reflectance is increased, window transmitted solar increases and convection heat rate is clearly affected. Among six surfaces including four walls, ceiling and floor, maximum convection heat rate occurs on the south wall in summer. On the other hand, ceiling and floor showed the lowest convection heat gain, since they are shared by adjacent floors.

• 한국태양에너지학회 논문집
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• 제22권1호
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• pp.23-30
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• 2002

본 연구는 축방향 내부 핀을 가진 열사이폰의 작동유체의 체적변화에 대한 응축 및 비등열전달 성능에 관한 연구이다. 열사이폰 내부의 작동유체는 증류수를 사용하였다. 열사이폰의 총체적에 대한 작동유체의 양을 변화시키면서 실험데이터를 산출하였다. 열사이폰의 응축부에 대한 열유속과 응축열전달계수를 구하였으며, 실험결과를 이론모델과 비교분석하였다. 실험결과로부터 열사이폰의 열전달 성능은 작동유체의 체적변화에 크게 의존하였다. 축방향내부 핀을 가진 열사이폰의 열전달 성능은 평튜브로 제작한 열 사이폰보다 크게 향상되었다. 이와 같은 열사이폰을 태양열 분야의 열교환기에 응용할 경우, 고성능화와 소형화할 수 있다. 그리고 산업현장에서 실제적으로 적용하기 위해 총열전달계수를 산출하였다.