• The Journal of Sustainable Design and Educational Environment Research
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• v.17 no.3
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• pp.1-8
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• 2018

We suggest improvement direction of energy-saving design based on analysis of current situation in school facilities. School facilities have large area among public buildings. While the number of students is decreasing, the number of school and energy consumption is increasing year after year. School facilities have excellent heat insulation property, but it requires further examination about excessive heat insulation plan. School facilities are using gas heat pump actively for cooling and heating, but has difference in use ratio of ground source heat pump by region. Thus School facilities requires active using of ground source heat pump and BIPV(Building Integrated Photovoltaic System).

• Progress in Superconductivity and Cryogenics
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• v.14 no.2
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• pp.32-35
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• 2012

The objective of the present work is to develop a precise instrument for measuring the thermal property of insulating material over a temperature range from 30 K to near room temperature by utilizing a cryocooler. The instrument consists of two thermal links, a test sample, heat sink, heat source and vacuum vessel. The cold head of the cryocooler as a heat sink is thermally anchored to the thermal link and used to bring the apparatus to a desired temperature in a vacuum chamber. An electric heater as a heat source is placed in the middle of test sample for generating uniform heat flux. The entire apparatus is covered by thermal shields and wrapped in multi-layer insulation to minimize thermal radiation in a vacuum chamber. For a supplied heat flux the temperature distribution in the insulating material is measured in steady and transient state. The thermal conductivity of insulating material is measured from temperature difference for a given heat flux. In addition, the specific heat of insulating material is obtained by solving one-dimensional heat diffusion equation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.113-114
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• 2017

Recently, Subway workers have died from lung cancer. According to the Epidemiological Survey of the Welfare Corporation Institute of Pulmonary Disease of the Welfare Corporation, the family members applied for industrial accidents. The radon concentration in the subway work area was found to exceed 10 times the recommended standard value of 148 becquerels (Bq/㎥) in domestic multipurpose facilities. In addition, as a result of the national indoor radon concentration survey conducted by the Ministry of Environment in 2010 and 2013, housing was found to be over 100 becquerels (Bq/㎥) in 41% of the surveyed subjects. In addition, it was found that in 2012, 16.3% of villages exceeded the radon standard value in the survey on natural radioactive materials containing groundwater.

• Korean Journal of Materials Research
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• v.26 no.10
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• pp.521-527
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• 2016

Geopolymers have many advantages over Portland cement, including energy efficiency, reduced greenhouse gas emissions, high strength at early age and improved thermal resistance. Alkali activated geopolymers made from waste materials such as fly ash or blast furnace slag are particularly advantageous because of their environmental sustainability and low cost. However, their durability and functionality remain subjects for further study. Geopolymer materials can be used in various applications such as fire and heat resistant fiber composites, sealants, concretes, ceramics, etc., depending on the chemical composition of the source materials and the activators. In this study, we investigated the thermal properties and microstructure of fly ash and blast furnace slag based geopolymers in order to develop eco-friendly construction materials with excellent energy efficiency, sound insulation properties and good heat resistance. With different curing times, specimens of various compositions were investigated in terms of compressive strength, X-ray diffraction, thermal property and microstructure. In addition, we investigated changes in X-ray diffraction and microstructure for geopolymers exposed to $1,000^{\circ}C$ heat.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.356-362
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• 2016

Light-weight concrete uses forming agents for reducing weight and high heat insulation property. However, the forming agents make problems of decreased volume and compressive strength of the concrete. This research aims to having weight-reduction and securing heat insulation property using recycled wasted form polyurethane without any forming agents. A small quantity of admixture used for constructability and avoiding material segregation. We picked admixtures from two different companies which shows evenly dispersed of wasted form polyurethane. This research conducts a study on the effect of mixing ratio of admixture on the light-weight concrete used wasted form polyurethane. As a result of the test, increased mixing ratio of the admixtures results reduced fluidity of concrete. On the other hand, percentage of moisture content and compressive strength are increased slightly. Combustibility performance and sound insulation performance are also secured, as well.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.4
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• pp.163-174
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• 2018

Consumer and property evaluation of wetsuit materials were conducted to obtain useful data for developing competitive products that meet consumer expectations and improving industrial competitiveness. Data were collected through online surveys of 213 domestic consumers who have experienced wearing wetsuit among marine leisure activities. Five types of commercial wet suit materials by brand and four types of commercial wet suit materials with the same quality by thickness were collected. Then, their physical properties, salt water resistance and thermal insulation rate were evaluated and compared. As a result, the most commonly used wetsuit material is 3 to 5 mm thick, and the basic jersey material is bonded on both sides. As a processing for imparting functionality, processing for improving warmth and reducing surface resistance are most frequently used. Consumers often feel uncomfortable when wearing a wetsuit, such as wearing comfort, weight, ease of movement, stretchability, and clothing pressure, which are different from those of casual wear. Also, mechanical strength and warmth were considered to be the most important criteria for selection of wetsuit material for purchase or rental. The mechanical properties of brand A and B were better than those of brand C, D, and E. Resilience and thermal shrinkage were better in brand C, D, and E. On the other hand, there was no significant difference in the physical properties due to the difference in thickness of the material at the same quality. Also, it was found that the thicker the material, the more stable it is in the heat. Brand A and B had superior salt water resistance than brand C, D, and E. In the thermal insulation test, brand A and B showed better insulation characteristics than brand C, D, and E, but the types of bonded fabric and surface finishing of materials were thought to have affected. In comparison of the thickness, the thicker the materials, the better the salt resistance and the thermal insulation.

• Composites Research
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• v.19 no.1
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• pp.9-14
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• 2006

Experimental investigation on heat transfer ratio was firstly performed with three types of sandwich panels such as the Carbon/Epoxy Skin-Aluminum Honeycomb and Balsa Core Sandwich Panel of 37mm thickness, the Carbon/Epoxy Aluminum Skin-Honeycomb Core Sandwich Panel of 57mm thickness (including insulator) and the Carbon/Epoxy Skin-Aluminum Honeycomb Core Sandwich Panel of 37mm thickness based on the KS F 2278:2003(Insulation test method of windows). In additional to this investigation, experimental tests were also done for evaluation of heat transportation ratio with the Aluminum Skin- Aluminium Honeycomb Sandwich Panels of 27mm and 35mm thickness, and Aluminum Skin-Foaming Aluminum Sandwich Panel of 27mm thickness by the KS F2277:2002 (Insulation measuring method of construction component-Calibration heat box method or protective heat box method). In this study, it was found that the larger net heat transfer cross sectional area between the skin and the sandwich core is given, the higher heat transportation ratio occurs. It was also found that the hybrid type insulation had better insulation characteristics compared to the non-hybrid type insulation.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.331-338
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• 2013

Under the paradigm of sustainable green growth at the national level, various researches and applications for energy saving in the construction field has been attempted. As a part of energy saving efforts, lightweight concrete was investigated for thermal insulation concrete with phase change material (PCM) which has high heat storage capacity. As a part of energy saving efforts, thermal insulation concrete was investigated and evaluated with lightweight aggregate impregnated by PCM which has high heat storage capacity. As a result, it is found that concrete with lightweight aggregate impregnated by PCM is effective to prevent its quality deterioration by reducing water absorption rate of lightweight aggregate. In addition, it has shown that concretes using lightweight aggregate and impregnated lightweight aggregate improve heat insulation property 33% and 40~43% compared with using normal aggregate, respectively. It is that the lightweight aggregate concrete with impregnated lightweight aggregate has 12~14% lower thermal conductivity than unimpregnated.

• Journal of the Korean Society of Costume
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• v.66 no.6
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• pp.110-121
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• 2016

The purpose of this study is to develop high value-added uniform design in response to climate change, and produce high sensitivity uniforms that conserve the energy of its wearers. The scope of the study encompassed entire production stage from the product planning stage to developing a prototype to collecting consumer ratings to securing intellectual property. The results of the study are as follows. First, the material was developed that maximizes insulation by replicating human body heat radiation and raising the temperature by 5 degree Celsius. Second, through Time to Market system, a luxurious synthetic wool material was developed, and warm effect was achieved. Third, pattern design engineering for easy movement and design development allowed the realization of uniform design that is compatible indoors and outdoors as well as respond to highly active climate change. Fourth, Fifth, the developed design was registered and intellectual property rights were obtained.

• Journal of the Korea Institute of Building Construction
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• v.2 no.2
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• pp.145-150
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• 2002

The hydration of cement paste occurs when the cement is miked with water. During the hydration, hydration heat causes the thermal stress depending on the site of concrete and the cement content. Especially in the high-strength concrete, we must give care to the concrete due to its large cement content. In this study conduction calorimeter and concrete insulation hydration heat meter were used to investigation the hydration heat characteristics of cement and concrete. To reduce hydration heat of high-strength concrete, several types of replacement of fly-ash and blast-furnace slag powder were used in this experiment. As a result of this study, it was found that hydration heat of high-strength concrete was reduced by replacement of fly-ash and blast-furnace slag powder. In case of high-strength concrete using blast-furnace slag powder, the max-heat arrival time was delayed but an effect of heat reduction was lower than a case of high-strength concrete using fly-ash, because it was considered that the heat-dependence property of blast-furnace slag powder was higher than that of fly-ash.