• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.7
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• pp.1833-1839
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• 1994

Experiments have been carried out to investigate the burning characteristics of waste tires in high temperature environments. The burning of waste tire chips consists of four stages ; evaporation of volatile matters, ignition, burning of volatile matters, and burning of solid carbon. Burning time of waste tire chips depends on the gas temperature and the initial weight of the chip. However, the environments. In the ceramic matrix burner with a ceramic radiation shield, the burning time of the waste tire chips becomes shorter than that without the shield. This is due to the increase in heat transfer to the tire chips by radiation.

• Fashion & Textile Research Journal
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• v.13 no.6
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• pp.959-965
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• 2011

The purpose of this study was to evaluate the effect of wearing induced micro current brassiere on the physiological responses of women. Four women participated to wear a different brassiere condition: with and without micro current chips. Subjects were carried out after wearing the induced micro current brassiere for 120minutes. Eardrum temperature, skin temperature, blood pressure, heart rate, thermal perception, humid perception, and comfort perception were obtained. The results were as follows. The brassiere with micro current chips showed better performance on weight loss than the brassiere without micro current chips. Participants in a higher level of BMI were more likely to lose greater weight. Mean skin temperatures decreased with micro current chips. Participants felt more comfortable for walking in micro current brassiere than in brassiere without micro current chips.

• Journal of the Korean Society of Safety
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• v.27 no.6
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• pp.26-30
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• 2012

It is difficult to determine the junction temperature because LED lightings are manufactured using several chips with low power. This paper reports on the finite element method of the determination of junction temperature in the GaN-based LEDs. The calculated junction temperature of the LED chip using FEM was compared with the experimentally measured data. As the results of this study, the junction temperature of LED chips with via holes is lower than that of LED chips without via hole. Therefore, the research of via hole is necessary to decrease junction temperature of LED chips.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.3
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• pp.28-39
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• 1994

We experimented on memory multichip modules to increase the packing density of memory devices and to improve their electrical characteristics. A 128K$\times$8bit SRAM module was made of four 32K$\times$8bit SRAM memory chips. The memory multichip module was constructed on a low-cost double sided PCB(printed circuit boared) substrate. In the process of fabricating a multichip module. we focused on the improvement of its electrical characteristics. volume, and weight by employing bare memory chips. The characteristics of the bare chip module was compared with that of the module with four packaged chips. We conducted circuit routing with a PCAD program, and found the followings: the routed area for the module with bare memory chips reduced to a quarter of that area for module with packaged memory chips. 1/8 in volume, 1/5 in weight. Signal transmission delay times calculated by using transmission line model was reduced from 0.8 nsec to 0.4 nsec only on the module board, but the coupling coefficinet was not changed. Thus, we realized that the electrical characteristics of multichip packages on PCB board be improved greatly when using bare memory chips.

• Journal of Energy Engineering
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• v.5 no.2
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• pp.193-197
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• 1996

A study was conducted on the oxidation behavior of U-0.75 wt% Ti chips (Depleted Uranium, DU chips) using an XRD and a thermogravimetric analyzer in the temperature range from 250 to 500$^{\circ}C$ in air. At the temperature lower than 400$^{\circ}C$, DU chips were converted to UO$_2$, U$_3$O$\_$7/, and U$_3$O$\_$8/ whereas at the temperature higher than 400$^{\circ}C$, DU chips were completely converted to U$_3$O$\_$8/, the most stable form of uranium oxide. The activation energy for the oxidation of DU chips is found, 44.9 kJ/mol and the oxidation rate in terms of weight gain (%) can be expressed as; dW/dt8.4${\times}$10$^2$e(equation omitted) wt%/min (250$\leq$T($^{\circ}C$) $\leq$ 500) where W=weight gain (%), t=time and T=temperature.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.117-123
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• 2015

The need for drop simulations for board-leveled flip chips in micro-system packaging has been increasing. There have been many studies on flip chips with various solder ball compositions. However, studies on flip chips with Sn-1.0Ag-0.5Cu and Sn-3.0Ag-0.5Cu have rarely been attempted because of the unknown material properties. According to recent studies, drop simulations with these solder ball compositions have proven feasible. In this study, predictions of the impact lifetime by drop simulations are performed considering Cu and Cu/Ni UBMs using LS-DYNA to alter the design parameters of the flip chips, such as thickness of the flip chip and size of the solder ball. It was found that a smaller chip thickness, larger solder ball diameter, and using the Cu/Ni UBM can improve the drop lifetime of solder balls.

• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.196-205
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• 2015

The aim of this study was to evaluate the fuel characteristics of thermally treated wood chips of the Larix kaempferi C. As torrefaction temperature was increased ($200^{\circ}C$ to $300^{\circ}C$), the carbon content, calorific value, and mass loss of torrefied wood chips increased significantly. The torrefied wood chips were shown to have hydrophobic properties even when only treated by mild torrefaction. The energy required to grind torrefied wood chips was reduced by the torrefaction process. Different sizes of wood chips were used in this study; however, this produced almost no difference in the fuel characteristics of processed Larix kaempferi C, except in the distribution of ground wood particles. Similar results were observed when the wood chips were torrefied for different lengths of time (15 min to 60 min) at a constant temperature. Torrefaction was shown to have positive effects on the fuel characteristics of Larix kaempferi C, including improved energy density, storage, and grindability.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1317-1326
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• 2015

This study investigated the metabolizable energy (ME) intake, net energy of production (NEp), heat production (HP), efficiencies of ME use for energy, lipid and protein retention as well as the performance of broiler chickens fed diets based on cassava chips or pellets with or without supplementation with an enzyme product containing xylanase, amylase, protease and phytase. The two products, cassava chips and pellets, were analysed for nutrient composition prior to feed formulation. The cassava chips and pellets contained 2.2% and 2.1% crude protein; 1.2% and 1.5% crude fat; and 75.1% and 67.8% starch, respectively. Lysine and methionine were 0.077%, 0.075%, and 0.017%, 0.020% protein material, respectively, while calculated ME was 12.6 and 11.7 MJ/kg, respectively. Feed intake to day 21 was lower (p<0.01) on the diet containing cassava chips compared to diets with cassava pellets. Enzyme supplementation increased (p<0.01) feed intake on all diets. Live weight at day 21 was significantly (p<0.01) reduced on the diet based on cassava chips compared to pellets, but an improvement (p<0.01) was noticed with the enzyme supplementation. Metabolizable energy intake was reduced (p<0.01) by both cassava chips and pellets, but was increased (p<0.01) on all diets by enzyme supplementation. The NEp was higher (p<0.01) in the maize-based diets than the diets containing cassava. Enzyme supplementation improved (p<0.01) NEp in all the diets. Heat production was highest (p<0.01) on diets containing cassava pellets than on cassava chips. It is possible to use cassava pellets in diets for broiler chickens at a level close to 50% of the diet to reduce cost of production, and the nutritive value of such diets can be improved through supplementation of enzyme products containing carbohydrases, protease, and phytase.

• Journal of the Korean Wood Science and Technology
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• v.19 no.2
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• pp.56-64
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• 1991

The destructed chips(Pinus rigida Mill) were sulfonated under different conditions and defiberated. The yields and strengths of pulp, fatty acid and resin acid in sulfonated chips were determined. The results of this work were as follows: 1) A sulfonation caused a yield reduction to 97.9~88.2% at single stage. and to 94.9~88.2% at two stage pretreatment. The pulp yields were rapidly draped with increasing cooking temperature from $130^{\circ}C$ to $150^{\circ}C$ 2) Pulp strengths were improved with iacreasing cooking temperature. A sulfonation with 5% $Na_2SO_3$/NaOH(8/2) at single stage and 2% NaOH-5% $Na_2SO_3$ at two stage were most effective and gave the best combination of strength properteis. 3) Fatty acid esters in chips were mostly consisted of palmitic and olleic acid. During a sulfonation the former increased extensively, and the latter was lost with increase of cooking times. The amount of pimaric type in the chips was relatively decreased by the pretreatnent and abietic-type increased. But the changes between two resin acid types were insignificant. 4) The effciency of pitch removal was dependant upon cooking liquor pH. To remove sufficiently the resinous substance, the chips must be sulfonated at over pH 12. Therefore, taking account of pitch removel, two stage sulfonation is considered suitable as reinforcement pulp for newsprint manufacture from pitch pine chips : 2% NaOH($60^{\circ}C$ 1 hr) at first stage and 5% $Na_2SO_3$ ($130^{\circ}C$, 1hr) at secund stage.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.206-210
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• 2001

Six Holstein$\times$indigenous multiparous dairy cows, $60{\pm}8$ days in milk, were used in a double $3{\times}3$ Latin square design to investigate the efficiency of milk production. The dairy cows were randomly allocated to total mixed rations (TMR) containing ground corn, ground corn plus cassava chips 50:50 and cassava chips as main sources of total non-fiber carbohydrates. Ether extract and calculated energy intakes for dairy cows fed TMR containing cassava chips were lower (p<0.05) than those fed TMR containing ground corn and ground corn plus cassava chips 50:50. There were no differences (p>0.05) in daily DM intake (3.51, 3.41 and 3.29% BW), in 4% fat corrected milk (19.66, 20.59 and 20.23%), in milk protein (3.37, 3.27 and 3.33%), and in solids-not-fat (9.03, 8.90 and 8.99%) but there were differences in cost of diets per kg of 4% fat corrected milk (40.75, 34.33 and 28.17%; p<0.01) for dairy cows fed TMR containing ground corn, ground corn plus cassava chips 50:50, and cassava chips. It can be concluded that the efficiency of milk production (4% fat corrected milk per dry matter intake) for dairy cows fed TMR containing cassava was greater than for those fed TMR containing corn.