• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.1
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• pp.14-18
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• 2016

A novel $Ce^{3+}$ doped $(Ce_xLu_{1-x})_3MgAl_3SiO_{12}$ phosphor was successfully synthesized by a conventional solid-state reaction. Heat-treatment temperature was controlled from 1250 to $1550^{\circ}C$ for 5 h. XRD and PL properties were analyzed for the optimum heat-treatment condition. Ce doping concentration was varied from 2.0 to 10.0 mol% for the optimum Ce doping concentration. The PL intensity, peak wavelength and FWHM were calculated with the Ce doping concentration, and evaluated for the application to LED packaging. Particle size and morphology were also characterized for synthesized phosphor sample at optimum heat-temperature and Ce doping concentration.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.874-878
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• 2013

Unlike Europe (particularly, Italy and Spain), where a number of studies have been conducted on the stressful effects of transport on rabbit welfare, few studies have been conducted on transportation of rabbits under hot, humid tropical conditions experienced in countries like Malaysia. We studied the effects of transportation in hot humid tropical conditions of Malaysia on physiometabolic changes in New Zealand white rabbits. Eighty experimental animals were divided into two groups of 40 bucks each and transported for either 3 or 1 h. Transportation caused a significant upsurge of aspartate aminotransferase, alanine aminotransferase and creatine kinase activities (p<0.001) though did not significantly affect lactate dehydrogenase (LDH) activity (p = 0.0706). Both transportation periods caused elevation in plasma glucose levels, lactic acidosis and dehydration as evidenced through elevated packed cell volume and plasma protein concentration. It was concluded that regardless of the duration, transport of rabbits under hot humid tropical conditions, resulted in heat distress since the rabbits showed hyperglycemia, hypercalcemia, lactacidemia, lymphocytopenia, dehydration and increase in blood enzyme activities.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.810-814
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• 2009

A experimental study of a high efficiency transport refrigeration system for sliced-raw fish transportation is presented in this paper. The refrigeration system, that is powered by the car engine, is equipped with heat storage for reverse cycle-hot gas defrost; the stored heat is used during defrost cycle of the system. The heat storage has size $400(L){\times}350(W){\times}250(H)\;mm$ and made of fin-tube heat exchanger. System performance and container operating conditions are experimentally investigated and analyzed under cooling and defrosting conditions with heat storage materials. The water is faster about 30% than paraffin in cooling-down time of heat storage materials with load and unload.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.778-784
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• 2012

In comparison with some other light sources, LED has merits such as increased life expectancy, fast response, pollution free, and high energy efficiency. Lately, due to development of LED with high brightness and capacity, LED has widely used in many industrial fields such as automotive, aviation, display, transportation and special lighting applications. Since the high heat generation of LED chips can cause a reduction in lifetime, degradation of luminous efficiency, and variation of color temperature, studies have been carried out on the optimization of LED packaging and heat sinks. In this study, experiments on measuring the heat generation rate of LED and the cooling performance of a heat sink were carried for analyzing the thermal characteristics of LED lighting system in free convection. From the results, dimensionless correlation on the cooling performance of heat sink in natural convection was proposed with Nusselt number and Rayleigh number as a guideline for designing cooling device of LED lightings.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.1
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• pp.26-36
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• 1997

Recently, the new refrigerating system, using non - fluorinated hydrocarbon refrigerants has to be developed for the agricultural fields. One of that kinds of systems is the cooling system using the water vapor and vacuum, in which the water evaporate at the low temperature under vacuum and absorb the large amount of the latent heat. If vapor with large amount of latent heat is removed from the system, the system is cooled accordingly. The characteristics of cooling under the vacuum was observed and measured using experimental apparatus, which is consisted of vacuum chamber, the ejectors, the pumps and the measurement apparatus. As the results of experiments, we know that the evaporation in the vacuum occurs vigorously when the materials to be cooled has more amounts of heat before cooling, and by which effects the materials can be cooled. The cooling vacuum system is more efficient than other methods when the agricultural products is chilled or dried.

• Proceedings of the Safety Management and Science Conference
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• 2012.11a
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• pp.245-252
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• 2012

Internal engine is the main power source of vehicle and is the main source of air pollution. To satisfy this getting rigorous emission regulation, it must be solved simultaneously the dilemma of reducing emission gas and increasing heat efficiency. Diesel engine is preferred compare with gasoline engine in aspect of energy consumption but it must be solved reducing the containing of NOx, CO and HC. In this study 1. Looking for alternative of performance improvement of Exhaust Gas Recirculation(EGR) which is emission gas reduction system, 2. Reducing malfunction of controlling emission gas 3. Made possible precision control.

• Journal of Dairy Science and Biotechnology
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• v.22 no.1
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• pp.27-35
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• 2004

The shelf lift of market milk should be determined based on the flavor which is influenced by environmental and sanitary conditions of dairy farm, milk processing plant, and storage and transportation facility as well as compositional quality, such as protein and fat, of the milk itself. The legal shelf life of market milk is often limited by microbiological quality, e.g. total bacterial count, coliform count, and food poisoning bacteria. The bacteria involved with milk spoilage and poisoning are originated from bacteria contaminating milk after pasteurization or spores surviving the heat treatment of pasteurization. The important factors which influence the shelf life of market milk are microbiological quality of raw milk, pasteurization condition, post-pasteurization contamination, and temperature during storage and transportation. The organoleptic quality and shelf life of market milk should be further improved by satisfying the consumer's taste, which depends on somatic cell count and bacterial count of milk, feed quality, foreign substance in milk, and physical treatment during processing and transportation.

• Steel and Composite Structures
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• v.15 no.4
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• pp.425-438
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• 2013

A new-styrofoam-concrete composite sandwich slab with function of heat insulation is designed. Four full-scale simply supported composite sandwich slabs with different shear connectors are tested. Parameters under study are the thickness of the concrete, the height of profiled steel sheeting, the influence of shear connectors including the steel bars and self-drilling screws. Experimental results showing that four specimens mainly failed in bending failure mode; the shear connectors can limit the longitudinal slippery between the steel profiled sheeting and the concrete effectively and thus guarantee the good composite action and cooperative behavior of two materials. The ultimate sagging bending resistance can be determined based on plastic theory. This new composite sandwich slab has high sagging bending resistance and good ductility. Additionally, these test results help the design and application of this new type of composite sandwich slab.

• Journal of the Korea Safety Management & Science
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• v.16 no.3
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• pp.185-194
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• 2014

Internal engine is the main power source of vehicle and is the main source of air pollution. To satisfy this getting rigorous emission regulation, it must be solved simultaneously the dilemma of reducing emission gas and increasing heat efficiency. Diesel engine is preferred compare with gasoline engine in aspect of energy consumption but it must be solved reducing the containing of NOx, CO and HC. In this study: 1. Looking for alternative of performance improvement of Exhaust Gas Recirculation(EGR) which is emission gas reduction system. 2. Reducing malfunction of controlling emission gas. 3. Made possible precision control.

• Journal of the Korean Society of Safety
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• v.32 no.5
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• pp.1-7
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• 2017

Forensic Engineering is the art and science of professionals qualified to serve as engineering experts in courts of law or in arbitration proceedings. Buses using compressed natural gas (CNG) trend to be extended in use internationally as optimal counterplan for reducing discharge gas of light oil due to high concern about environment. However, CNG buses is equipped with composite pressure vessels (CPVs); since the CPVs contain compressed natural gas, the risks in the case of accident is very high. In this study, the bursting test for the pressure vessel depending on the heat treatment conditions of the vessel in which the actual ruptured accident occurred, after the bursting test, the fracture pattern analysis had performed. The mechanical materials properties test using Instrumented Indentation Test had performed to confirm the mechanical properties for each heat treatment cases. Also, the fractography analysis and metallographic analysis had performed to find out the difference of each heat treatment case. By comparing normal vessel with abnormal vessel which have defect of heat treatment conditions in term of the bursting patterns and characteristics of containers using various forensic engineering methods, especially, it is possible to understand how important the heat treatment process is in the high pressure vessel unlike any product.