• The Korean Journal of Nuclear Medicine
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• v.21 no.2
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• pp.183-190
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• 1987

In Raynaud's phenomenon, the authors measured finger blood flow after ice water exposure by analyzing the time activity curve of radionuclide angiography on both hands. The results were as follows: 1) The digital blood flow did not decrease after ice water exposure in normal subjects. 2) In the patients with Raynaud's phenomenon, there were two groups: the one had decreased digital blood flow after cold exposure, and the other had paradoxically increased digital blood flow after cold exposure. 3) There was no difference in the digital blood flow of hand in room temperature between the normal and the patients with reduced digital blood flow after cold exposure, but the digital blood flow of the hand in room temperature was markedly reduced in the patients with paradoxically increased flow after cold exposure. 4) In the static image the difference was not significant in comparision with the dynamic study, because it represents pooling of the blood in the vein rather than flow. 5) After the treatment with nifedipine, the digital blood flow increased. In conclusion, the radionuclide angiography was useful in measuring the digital blood flow in Raynaud's phenomenon, and further studies with various drugs is expected.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.223-228
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• 1999

The storage effects of satsuma mandarin(Citrus unshiu Marc. var. miyagawa) by humidity control during storage; 90% relative humidity (RH) and 85% RH at $3^{circ}C$, and room temperature were investigated. After 98 days' storage, weight losses were 3.40% for 90% RH, 6.92% for 85% RH, and 11.87% for room temperature storage. Decay ratio was increased rapidly from 3.87% on 98 days' to 48.75% on 126 days' storage for 90% RH. Soluble solids and flesh ratio were declined gradually, but the differences were not significantly. Firmness of fruits was continuously reduced during storage, especially on room temperature storage by the softening of the fruits. Acid content and vitamin C were gradually reduced during storage. Coloration was continuously progressed on room temperature, compared to cold storage. In order to keep freshness of the fruits, optimum storage period of early variety of Satuma mandarin was regarded for 100 days at $3^{circ}C$, 85% RH on the basis of sensory evaluation and chemical compositions.

• Analytical Science and Technology
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• v.13 no.4
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• pp.412-422
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• 2000

The polymeric FAB materials of air shower used in clean room of wafer industry have been outgassed with the dynamic headspace (ca.$100^{\circ}C$) for half an hour, and analyzed using GC-MS. The air in the clean room running air shower was sampled using sorbent tube method, and the organic compounds adsorbed in the sorbent tube were extracted using Soxhlet extraction method, and analyzed using GC-MS. The analytical results from FAB materials of air shower (electric over current relay, acryl plate. polycarbonate window, filter, fan housing, steel galvanized cold plate and canvas buffer) indicated that most of chemicals were originated from polymer fragments of FAB materials. Their analytical results have been compared with those from the air of clean room running air shower. These comparative results could lead to identify whether the sources of trace organic contaminants in clean room air are originated from the polymeric FAB material of air shower.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.6
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• pp.628-633
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• 2012

It was found that the pure hydrogen-air pre-mixture was self-ignited at a high compression ratio without any assisting method in room temperature, thus refuting the preconception that compression ignition of hydrogen engine was impossible. Therefore, in order to analyze the correlation of compression ignition condition at cold start with hydrogen HCCI engine clearly, the possibility of compression igniting compression ratio is investigated with the change of equivalence ratio and engine speed, experimentally. As the results, it is confirmed that the possibility of compression-igniting compression ratio at cold start was decreased by increasing equivalence ratio due to decreasing auto-ignition temperature. In addition, it is grasped that the possibility of compression-igniting compression ratio at cold start is decreased around 14.9% by increasing engine speed at same supply energy.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.322-326
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• 1999

In this study, cold-rolling and appropriate annealing was adopted for the grain refining of Cu-26.65Zn-4. 05Al-0.31Ti(wt%) shape memory alloy. For the cold deformation of this alloy the ducti1e $\alpha$-phase must be contained. After heat treatment at $550^{\circ}C$ the $(\alpha+$\beta)$-dual phase with 40vol.% $\alpha$-phase was obtained which could be rolled at room temperature. This alloy was cold rolled into a final thickness of 1.0mm with total reduction degrees of 70% and 90%. The rolled sheets were betanized at $800^{\circ}C$ for various times, then quenched into ice water. The grain size of co]d rolled samples were $60~80\mu\textrm{m}$ which is much smaller comparing with the hot-rolled samples. And the 90% rolled sample showed smaller grain size than the case of the 70% rolled one. The small grain size had influence on the phase transformation temperatures and stabilization of the austenitic phases.

• Korean Journal of Materials Research
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• v.15 no.10
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• pp.632-638
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• 2005

To investigate the effect of Mo and Cu contents on tensile strength of cold drawn stainless steel 304H wires, metallographical and mechanical tests were performed for the wire specimens drawn to different drawing strains at room temperature. It was confirmed that the contents of Mo ana Cu have little influence on the tensile strength of drawn specimens, even though the strain induced martensite transformation decreased with increasing the contents of Mo and Cu. These results were explained by the strengthening of the formed martensite itself due to the solid solution effect of interstitial solutes, carbon and nitrogen. The contents of these elements were slightly higher in the specimens containing additionally added Mo and Cu.

• Journal of Preventive Medicine and Public Health
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• v.20 no.2 s.22
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• pp.215-220
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• 1987

Under the extreme change of the environment, animals react physiologically to adapt to the stress and secrete catecholamines. Cold exposure is a kind of the environmental stress. Author tried to determine the amount of catecholamines in rat urine as a parameter of physiological response to cold stress. Urinary catecholamine was measured by using HPLC with fluorescence detector, cation exchange column prepacked with Bio·Rex 70 and ammonium pentaborate as catecholamine eluent. The amount of dopaminc in normal state rat urine was 42.0 ng, but under the low temperature of $5^{\circ}C$, the dopamine amount was increased to 221.25 ng/5 ml. Above findings are suggesting that catecholamine secretion, especially dopamine, increases in the stressful condition such as cold exposure.

• Transactions of Materials Processing
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• v.8 no.6
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• pp.541-553
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• 1999

Cold forging is a special type of forging process in which metal is forced to flow plastically under compressive force into a variety of shapes in room temperature. Gear blank, which is produced by cold forging, is concerned with the production method of transmission gear. Based on the results of simulation of the current four-stage process, the gear blank forging process for improving the conventional process sequence is designed. The rigid plastic finite element analysis for improving the conventional process. The new process consists of three stage operations with one annealing treatment after first operation. Based on the results of simulation of the proposed process, a required equipment could be selected. The new designed process appears to be more economical in producing the gear blank.

• Transactions of Materials Processing
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• v.10 no.1
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• pp.67-74
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• 2001

The cold forging process to produce a long-neck flange is investigated by using model material test. The two stage process with optimum design condition is examined using plasticine, which is suitable to model steel at room temperature. The similarity theory is employed to estimate the forging load of each sequence by strict application of similarity condition between steel(AISI 1015) and plasticine material The model test results are compared with the simulation results and shows good agreement. The proper forging process with least forming energy can be resulted in $25^{\circ}$ of extrusion semi-die angle.

• Journal of the Korean Society of Radiology
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• v.7 no.1
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• pp.99-106
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• 2013

The purpose of this study was to after induced delayed onset muscle soreness, the purpose of this study is to present the effective way on skin temperature changes and cold pain for 14 subjects during to applied with only Cold-jet stream and Cold-jet stream with infra red. 14 healthy men and women who delayed onset muscle soreness eccentric contractions induced by exercise and then the biceps alone was applied to the Cold-jet stream. We measured the time that skin temperature fall from room temperature to $10^{\circ}C$(first period), the time rewarmed from $10^{\circ}C$ to $20^{\circ}C$(second period), the time fall again to $10^{\circ}C$(third period) and the time rewarmed again to $20^{\circ}C$(fourth period). Cold-jet stream with infrared combination therapy was performed with the same method. Results of this study were 1st and 2nd experimental cooling experiments in the to fall to $10^{\circ}C$ Cold-jet stream with infrared combination therapy than in the Cold-jet stream was longer(p<.05). At second period, It took longer in Cold-jet stream with infrared rewarmed than Cold-jet stream to rewarm skin(p<.05). Cold-jet stream with infrared combination therapy than Cold-jet stream had less incidence of cold pain(p<.05). Thickness of biceps brachii were found significant difference related measurment each group was consistent. In this study, Cold-jet stream with infrared combination therapy more effective than Cold-jet stream in reduced cold pain and lowering skin temperature. This work was supported by education capacity building project fund of Taegu Science University, 2012.