• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.85-86
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• 2012

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.920-924
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• 2011

ZnO crystals with belt and comb shapes were synthesized without any catalysts through a simple thermal oxidation of ZnS powder in alumina crucible under air atmosphere. X-ray diffraction (XRD) pattern revealed that the ZnO crystals had wurtzite structure of hexagonal phase. Energy dispersive x-ray (EDX) spectra showed that the ZnO was of high purity. In the cathodoluminescece spectra obtained for the ZnO crystals with belt and comb shapes, a strong ultraviolet emission centered at 380nm was observed, which indicates the ZnO crystal has high crystalline quality.

• Textile Coloration and Finishing
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• v.12 no.2
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• pp.79-88
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• 2000

Draw textured yarns have many differences with yarn quality as well as wearing, due to the bulkiness, thermal and physical properties according to the false twist texturing system. In order to improve such property, many studies have been accomplished for developing good textured yarns and their fabrics, but these have been essentially obtained by experimental data or mathematical analysis. This study surveyed various properties of DTY produced by false twist texturing system, namely pin and crossed-belt false twist insertion systems. And 6 yarn specimens of 2 group(pin twisting type, belt twisting type) were measured and analysed.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1016-1023
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• 2006

The water content of dewatered cake produced from belt press dewatering equipment was about 75 wt% which was some high to handle it, so the equipment contained a limit at the economical and environmental aspect. The thermal dewatering equipment built as an alternative to overcome several problems was set up at the sludge treatment field and estimated some feasibility as comparison with the dewatering performance of belt press. First, dewatering properties of waterworks sludge was analyzed by monthly. The sludge of a water shortage season contained a high organic content which led to be difficult to dewater the cake, the other side the sludge of rainwater season was ease to dewater because of low organic content. According to the results to analysis the water content of dewatered cake produced from two equipments on the base of the seasonal dewatering properties, the water content of dewatered cake produced from thermal dewatering for sludge of water shortage season was $41.6{\sim}48.3$ wt% and $71{\sim}84$ wt% from belt press. In the case of rainwater season, the water content of dewatered cake produced from thermal dewatering was $34{\sim}37.7$ wt% and $57{\sim}70$ wt% from belt press. It was understood that thereduction of water content of cake by thermal dewatering was larger than belt press. The economical aspect for two equipments was evaluated on considering the reduction of cake treatment amount as the decrease of water content of cake. When putting the cost index of thermal dewatering into 100, belt press was 121. This meant that thermal dewater was more economical than belt press by about 20% in the side of construction and operation. In conclusion, thermal dewatering equipment was estimated by producing the low water content dewatered cake as well as being operated with low coat.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.2
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• pp.79-86
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• 2011

Cold-air drainage and pooling occur in most mountain valleys at night. Local climates with cold-air pooling could affect phenology and distribution of crop plants. A high resolution infrared imaging radiometer was used to visualize the cold-air drainage and thermal belt formation over a small mountainous watershed (ca. $10{\times}5{\times}1$ km for the maximum length${\times}$width${\times}$depth). Thermal images on $640{\times}480$ pixels were scanned across the Akyang valley (south of Mt. Jiri National Park) by the radiometer installed at a local peak ('Hyongjebong', 1,117 m a.s.l.) at dawn of 17 May 2011, when the synoptic condition was favorable for the surface cooling and cold-air drainage. Major findings are: (1) Cold-air drainage and accumulation was clearly identified by the lowest brightness temperature mainly at the valley bottom. (2) So-called 'thermal belt' with higher brightness temperature was found partway up the valley sidewalls and showed up to $5^{\circ}C$ departure from the valley bottom temperature. (3) Digital thermography showed feasibility for validation of the high definition geospatial temperature models currently in use for the plot-specific agrometeorological service.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.973-978
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• 2007

In this paper, we make a study of a thermal deformation by FEM and test to define the deformation mode of the Vacuum-Cleaner's Nozzle-Cover. In FEM analysis, 3 different conditions were considered separately, such as (1) Compressive force by Belt tension, (2) Friction heat between Belt and Shaft and (3) Compressive force combined with heat. Throughout FEM analysis it was found that the deformation was caused by heat and it was proved through a simulation test with a real product.

• The Journal of the Petrological Society of Korea
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• v.4 no.2
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• pp.178-184
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• 1995

The K-Ar ages of biotites, obtained from thirteen pelitic schists in the Jeungpyeong-Deokpyeong area, central Ogcheon metamorphic belt, range from 89 Ma to 213 Ma except for one specimen. These K-Ar ages systematically decrease as the distance between the analyzed specimen and the Jurassic or Creataceous granite decreases. The K-Ar ages of b~otites adjacent to the Jurassic and Cretaceous granites are 166 Ma and 89 Ma, respectively. Thus, the biotite ages are interpreted to result from the partial or complete resetting by thermal activities in association with the intrusion of Mesozoic granites, following the regional-thermal metamorphism at Late Triassic to Early Jurassic times.

• Korean Journal of Materials Research
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• v.30 no.7
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• pp.338-342
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• 2020

Tin oxide (SnO₂) nanocrystals are synthesized by a thermal evaporation method using a mixture of SnO₂ and Mg powders. The synthesis process is performed in air at atmospheric pressure, which makes the process very simple. Nanocrystals with a belt shape start to form at 900 ℃ lower than the melting point of SnO₂. As the synthesis temperature increases to 1,100 ℃, the quantity of nanocrystals increases. The size of the nanocrystals did not change with increasing temperature. When SnO₂ powder without Mg powder is used as the source material, no nanocrystals are synthesized even at 1,100 ℃, indicating that Mg plays an important role in the formation of the SnO₂ nanocrystals at temperatures as low as 900 ℃. X-ray diffraction analysis shows that the SnO₂ nanocrystals have a rutile crystal structure. The belt-shaped SnO₂ nanocrystals have a width of 300~800 nm, a thickness of 50 nm, and a length of several tens of micrometers. A strong blue emission peak centered at 410 nm is observed in the cathodoluminescence spectra of the belt-shaped SnO₂ nanocrystals.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.118-121
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• 2003

PET는 의류용과 비의류용에서 다양화 된 소재로 많이 사용되고 있다. 그러나, 일반적으로 생산되는 regular 絲의 경우 경쟁력이 떨어지기에 고부가가치의 소재를 생산하기 위한 많은 연구가 현재 진행중이다. 최근 국내 원사 Maker에서는 고속생산 및 자동화에 따른 대량생산 System으로 제조원가 절감에 주력하는 한편 기존 공정에서 차별화 소재를 생산 할 수 있는 연구를 계속하고 있다. (중략)

• Elastomers and Composites
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• v.44 no.3
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• pp.299-307
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• 2009

The effects of reinforcing materials on durability and mechanical properties of V-rib belt were investigated. Cotton fiber and ZnO were used as a filler for CR, and cotton and aramid fiber were used for EPDM rubber compounds. These materials were prepared as a specimen and V-rib belt for heat resistant and mechanical test. High contents of ZnO give improved wear resistance, and higher contents of cotton fiber showed higher durability in high rotation speed but lower wear resistance for CR rubber compounds. Using the aramid and cotton fiber together in EPDM rubber compounds, thermal and wear resistance were improved simultaneously. The material containing EPDM matrix showed better durability and wear resistance than those of containing CR matrix comparing in the same cotton fiber contents.