• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.109-112
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• 2008

In this work, a mathematical heat transfer model of a walking-beam type reheating furnace that can predict the formation and growth of the scale layer, which is produced due to oxidative reaction between the furnace oxidizing atmosphere and the steel surface in the reheating furnace, has been developed. The model can also predict the heat flux distribution within the furnace and the temperature distribution in the slab and scale throughout the reheating furnace process by considering the heat exchange between the slab and its surroundings in the furnace, including radiant heat transfer among the slabs, the skids, the hot gases and the furnace wall as well as the gas convection heat transfer in the furnace. Using the model developed in this work, the effects of the scale layer on the heat transfer characteristics and temperature behavior of the slab is investigated. A comparison is also made between the predictions of the present model and the data from an in situ measurement in the furnace, and a reasonable agreement is founded.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.3
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• pp.148-158
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• 2003

In this study, a user oriented CFD program for optimum design of a regenerative combustion furnace, REBURN was developed. For user's convenience, user friendly Graphic User Interface was made and the renumbering interface program was developed in order to directly input any generated mesh system from ICEM CFD/FEA. Also an automatic processing system for switching mode was developed. The program was verified through compahng with commercial CFD code about regenerative combustion furnace. Then, numerical simulation of real walking beam furnace used in real industry was performed and the parametric analysis was studied about the arrangement mode. As a results, the uniform temperature was appeared in the cross mode.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.321-324
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• 2005

The main purpose of the present study has been placed on investigating the effects of controlled rolling and cooling on the microstructures and mechanical properties of C-Si-Mn-V steels for cold forming. The steels were manufactured in vacuum induction melting(VIM) furnace and casted to 1.1ton Ingots and the ingots were forged to $\Box150$ billet. The forged billets were reheated in walking beam furnace and rolled to coil, the stocks were rolled by Controlled Rolling and Cooling Technology (CRCT), so rolled at low temperature by water spraying applied in rolling stage and acceleratly cooled before coiling. Rolled coils were cold drawed to the degree of $27\%$ of area reduction without heat treatment. Microstructual observation, tensile test, compression test and charpy impact tests were conducted. The mechanical properties of the steels were changed by area reduction of cold drawing and it is founded that there are optimum level of cold drawing to minimize compression stress for these steels. From the result of this study, it is conformed that mechanical properties and microstructure of C-Si-Mn-V steels for cold forming were enhanced by accelerated cooling and founded optimum level of cold drawing.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.45-49
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• 2011

The aim of study intends to investigate effect of weight of fire-protective clothing for physical balance and agility after maximum physical activity and to provide the base data for the safety of firefighter. For evaluation of static and dynamic-balance, the closed-eyes foot balance and the beam-walking were performed respectively. For evaluation of static and dynamic-agility, the whole body reaction and the side-step were carried out. This study demonstrates that after maximum physical activity, the weight of fire-protective clothing effects on physical static-balance and dynamic-agility and suggests that it could be useful for actual safety field studies of firefighters.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.1
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• pp.1-12
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• 2010

Objectives : Cool Pharmacopuncture for static blood is a famous pharmacopuncture treatment that treated disease caused by static blood. Hyolhae(Sp10) is also a famous point of acupuncture that treated that. This study was designed to evaluate the effects of Cool Pharmacopuncture for static blood into Hyolhae(Sp10) on BAX and BCL-2 expression in the experimental traumatic brain injury(TBI) rats. Methods : Male rats were divided into 3 groups. I was no treatment after TBI. II was treatment with needle-prick acupuncture after TBI. III was treatment with Cool Pharmacopuncture for static blood into Hyolhae(Sp10) after TBI. The author carried out neurological motor behavioral test, histological assessment test. Neurological motor behavior tests consist of rotarod test, beam-walking test and postural reflex test. In the histological assessment test, BAX and BCL-2 expression, hematoxylin & eosin staining were experimented. Results : In neurological motor behavior tests, motor and cognitive function recovery was significantly increased in the II, III as compared with I (p<0.05). Especially III was significantly increased as compared with II (p<0.05). BAX expression was significantly decresed in order of the III, II, I after 7 and 14 days later. BCL-2 expression was investigated in the III, II as compared with I. Especially Most incresed expression was experimented in the III. Conclusions : According to the above results, Cool Pharmacopuncture for static blood can inhibit apoptosis of cells after TBI in rats by contol of BAX and BCL expression.

• The Journal of Korean Physical Therapy
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• v.13 no.2
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• pp.281-292
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• 2001

This study was performed to investigate the effect of therapeutic exercise on brain-derived neurotrophic factor manifestation after global brain ischemia in rats. Nine rats with global ischemia were divided at random into two group. In the control group, three rats remained in cage. But, in the end, two rats were alive. In the therapeutic exercise group, six rats remained. The five rats of this group was swam for 30 minutes everyday for a week. The brain-derived neurotrophic factor expression was identified from immunohistochemistry. The results of this study were as follows : 1. In the control group, a little expression of brain-derived neurotrophic factor was observed at cortex and hippocampus layer, but cell body and axon was observed obscurely. 2. In the experimental group, a much expression of brain-derived neurotrophic factor was observed at cortex and hippocampus layer, and cell body and axon was observed clearly. In the neurological examination(beam-walking test). experimental group was obtained higher 1.4 points than control group. BDNF expression was increased by swimming for 30 minutes everyday for a week. Therefore, therapeutic exercise contribute to brain plasticity after brain ischemia.

• The Journal of Internal Korean Medicine
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• v.32 no.1
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• pp.43-55
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• 2011

Objectives : Sokmyeung-tang(SMT) has been used for treatment of CVA in traditional oriental medicine, so this study was designed to evaluate the effect of SMT's protection on brain cell damage against the oxidative stress that was affected by CVA, We also investigated the effect of motor function improvement and neurotrophic factor in ischemic cerebral damaged rats. Methods : We measured cell viability after administrating SMT, chemicals(Paraquat, SNP, rotenone, and $H_2O_2$) which cause oxidative stress, and both SMT and chemicals. We carried out neurobehavioral evaluation(Rotarod test, Beam-walking test, postural reflex test) and observed BDNF (brain-derived neurotrophic factor) expression by injecting SMT into ischemic cerebral damaged rat. Results : Through this study, we observed the following three results. First, brain cell death caused by paraquat, rotenone, and $H_2O_2$ significantly decreased with the treatment of SMT. Second, neuronal movement function in ischemic cerebral damaged rats was significantly improved by the treatment of SMT. Third, BDNF in ischemic cerebral damaged rats increased with the treatment of SMT. Conclusions : SMT protects brain cells from damage induced by oxidative stress (Paraquat, rotenone, $H_2O_2$). SMT also improves neuronal movement function and increases BDNF in ischemic cerebral damaged rats.

• The Journal of the Korea Contents Association
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• v.9 no.1
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• pp.348-358
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• 2009

Diffuse axonal injury(DAI) is a common form of traumatic brain injury and thought to be a major contributor to cognitive dysfunction. Physical activity has been shown to beneficial effects on physical health and influences in hippocampus which is an important location for memory and learning. The purpose of this study was to investigate the effect of motor training on motor performance and axonal regeneration in hippocampus through the immunoreactivity of GAP-43 after diffuse axonal injury in the rats. The experimental groups were applied motor training(beam-walking, rotarod, and Morris water maze) but control groups were not. The time performing the motor tasks and GAP-43 immunohistochemistry were used for the result of axonal recovery. There were meaningful differences between experimental groups and control groups on motor performance and GAP-43 immunohistochemistry. The control groups showed increasing tendency with the lapse of time, but experimental groups showed higher. Therefore, Motor training after DAI improve motor outcomes which are associated with dynamically altered immunoreactivity of GAP-43 in axonal injury regions, particularly hippocampus, and that is related with axonal regeneration.

• The Journal of the Korea Contents Association
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• v.8 no.9
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• pp.194-203
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• 2008

CIMT(Constraint Induced Movement Therapy) is to improve the function and use of damaged upper limbs by not only confinement of unaffected limbs' exercise but also inducement of affected limbs' one. The purpose of the study is to verify the effect of CIMT by means of motor behaviour test and immunohistochemistry, using animal models. This study was analyzed using 40 male Sprague-Dawley rats as the experimental groups and 40 ones as the control groups. The rats were divided into two random groups : one group as an experimental group which was operated on under anesthesia and removed somatomotor regions with CIMT and the other as the control group without CIMT.Postural Reflex Test, Beam Walking Test, Limb Placement Test and Immunohistochemistry were run on the day 1, 3 , 7 and day 14 following surgery to each 10 rat. As a result, this study demonstrates that CIMT might be an effect method to verify the plasticity of central nervous system as motor behaviour test made all high scores (p<.05) and BDNF was high too in experimental groups.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.11-18
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• 2020

The present study was aimed to explore the neuroprotective role of imatinib in global ischemia-reperfusion-induced cerebral injury along with possible mechanisms. Global ischemia was induced in mice by bilateral carotid artery occlusion for 20 min, which was followed by reperfusion for 24 h by restoring the blood flow to the brain. The extent of cerebral injury was assessed after 24 h of global ischemia by measuring the locomotor activity (actophotometer test), motor coordination (inclined beam walking test), neurological severity score, learning and memory (object recognition test) and cerebral infarction (triphenyl tetrazolium chloride stain). Ischemia-reperfusion injury produced significant cerebral infarction, impaired the behavioral parameters and decreased the expression of connexin 43 and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in the brain. A single dose administration of imatinib (20 and 40 mg/kg) attenuated ischemia-reperfusion-induced behavioral deficits and the extent of cerebral infarction along with the restoration of connexin 43 and p-STAT3 levels. However, administration of AG490, a selective Janus-activated kinase 2 (JAK2)/STAT3 inhibitor, abolished the neuroprotective actions of imatinib and decreased the expression of connexin 43 and p-STAT3. It is concluded that imatinib has the potential of attenuating global ischemia-reperfusion-induced cerebral injury, which may be possibly attributed to activation of JAK2/STAT3 signaling pathway along with the increase in the expression of connexin 43.