• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.265-274
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• 2024

The current research focuses on the development of a numerical approach to forecast strongly subcooled flow boiling of FC-72 as the refrigerant in various vertical minichannel shapes for high-heat-flux cooling applications. The simulations are carried out using the Volume of Fluid method with the Lee phase change model, which revealed some inherent flaws in multiphase flows that are primarily due to an insufficient interpretation of shearlift force on bubbles and conjugate heat transfer against the walls. A user-defined function (UDF) is used to provide specific information about this noticeable effect. The influence of shape and the inlet mass fluxes on the flow patterns, heat transfer, and pressure drop characteristics are discussed. The computational results are validated with experimental measurements, where excellent agreements are found that prove the efficiency of the present numerical model. The findings demonstrate that the heat transfer coefficient decreases as the mass flux increases and that the constriction design improves the thermal performance by 24.68% and 10.45% compared to the straight and expansion shapes, respectively. The periodic constriction sections ensure good mixing between the core and near-wall layers. In addition, a slight pressure drop penalty versus the thermal transfer benefits for the two configurations proposed is reported.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.137-146
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• 2007

Objectives : Investigation of the anitstress effects of Lycii Radicis Cortex. Methods : Behavior was measured in PAT and FST after applying stress to rats. Also, TH expression-degree in the regions of VTA and LC was measured, respectively. Results : The memory was improved in the LH 50mg/kg treated group in the passive avoidance test(P<0.01). The duration of immobility in the forced swimming test was significantly decreased in the LR 50mg/kg and 400mg/kg treated groups(P<0.0l). Stress-induced TH increases were meaningfully suppressed in the LR 100mg/kg and 400mg/kg treated group(P<0.001). Conclusion : Lycii Radicis Cortes has the effect of memory improving and antidepressant.

• International Journal of Railway
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• v.5 no.4
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• pp.163-166
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• 2012

Many different types of floating slab track have been developed and installed around the world to reduce vibrations and noise originating in the surrounding environment. The main objective of this study is to examine the influence of slab length on behavior of floating slab track based on rail-slab-isolator interaction. The floating slab track is modeled by the connection between rail, slab, isolator, and slab mat in the transition zone. All elements were assembled in a simplified two-dimensional (2D) finite element model (FEM). The maximum length of FST is then investigated based on the maximum additional rail stress criterion as described in UIC 774-3R since no fully accepted design criteria for the slab length in FST systems currently exist.

• Speech Sciences
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• v.10 no.4
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• pp.229-239
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• 2003

The purposes of this study are; to investigate the swallowing mechanism of stroke patients with different consistencies through the modified barium swallowing(MBS); and to establish preliminary data on the differences in swallowing durations. 4 different kinds of consistency-water, nectar, pudding, and crackers-were given to 6 stroke patients and their swallowing durations recorded through the fluoroscopy were measured in 1/100 second units. The results show that first swallowing time(FST), the oral preparatory duration(OPD), and the pharyngeal response duration(PRD) were delayed in swallowing thicker consistencies. However, water exhibited delayed oral and pharyngeal phase relative to its consistency and 50% of subjects showed oral loss of water. The relationship between consistencies and swallowing durations and the clinical issues on the stroke population were discussed.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.24 no.2
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• pp.69-74
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• 2018

Background: The purpose of this study was to investigate the effect of a complex exercise program for elderly people who had experienced a fall on their balance ability and proprioception when their visual sense was blocked. Methods: The subjects were 24 elderly people with experienced fall. They were equally and randomly divided into a blind group and a general group. The subjects performed the complex exercise program for 30 minutes, twice a day, five days a week for 4 weeks a total of 20 times. Outcome measures were the 10-meter walking test (10MWT), Berg balance scale (BBS), Fukuda stepping test(FST), proprioception test (PT). Results: After the intervention, the blind group showed improvements in 10MWT, BBS, FST, PT. The general group showed improvements in 10MWT and PT. Conclusions: The complex exercise program for elderly people helped enhance their balance ability and proprioception.

• International Journal of Computer Science & Network Security
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• v.23 no.3
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• pp.203-207
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• 2023

A frequency reconfigurable antenna based on graphene and used for multi-band wireless communications is presented in this article. The proposed antenna, which consists of two radiating rectangular loops with a graphene extension, is analyzed for Global Positioning System (GPS) and Iridium applications. Its operating frequency is tuned through the implementation of a layer of graphene and thereby adjusting the applied gate bias. Furthermore, the results show a novel use of graphene for microwave frequencies while achieving a frequency reconfiguration with an improvement of the impedance matching and the gain. The results also prove the importance of graphene, with its exceptional properties, for a promising future in nano-electronics.

• Korean Journal of Plant Resources
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• v.25 no.6
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• pp.657-663
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• 2012

Muscle strength and endurance activities of Korean ginseng (Panax ginseng C. A. Meyer; KG) were compared with those of wild simulated cultivation ginseng (WCG) in mice. Fifty male ICR mice were divided into five groups: A (vehicle); B (WCG 100 mg/kg); C (WCG 500 mg/kg); D (KG 100 mg/kg); E (KG 500 mg/kg). Subsequently, the mice were subjected to the forced swimming test (FST) and treadmill test at the $4^{th}$ and $7^{th}$ weeks. The glycogen content in the muscle and blood analysis (levels of glucose, triglyceride (TG), IGF-1) were also performed immediately after the last FST and treadmill test at the $7^{th}$ week. Immobility times in FST were shorter in WCG- than KG-treated groups, and the results of the treadmill tests were also significant except for KG-treated at 100 mg/kg. The glycogen content was increased in both groups with a peak at 500 mg/kg of WCG groups. Serum concentrations of TG and glucose were decreased by administration of KG and WCG and all treated groups showed increase in the level of IGF-1 in serum. These results suggest that KG and WCG supplementations are effective in escalating the muscle strength and endurance.

• Herbal Formula Science
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• v.12 no.2
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• pp.77-93
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• 2004

Depression is a sort of mental disorder which is very common. To treat depression, many drugs such as TCA, MAOI are developed and used. But they have a lot of side effects, so it needs to develop drugs without side effects or with less side effects. Herbal medicines have been used to treat diseases not only physical but also mental and have less side effects. therefore, it has been thoght the need to develop herbal medicine with antidepressant effect. The purpose of this study was to reseach antidepressant effect and influence on monoamines of chunwangboshimdan thought to have antidepressant according to ancient medical book- donguibogam- and recent reports. We used 'forced swimming test(FST)' to know antidepressant effect of chunwangboshimdan and HPLC to check the influence on monoamines and their metabolites(norepinephrine, dopamine, DOPAC, HVA, serotonin, 5-HIAA) of chunwangboshimdan after divided into cerebral cortex, striatum, hypothalamus and hippocampus. The results were obtained as follows: In the study of antidepressant effect by 'forced swimming test(FST)'method, chunwang boshimdan had a significant antidepressant effect. In the study of influence on monoamines by HPLC, chunwangboshimdan mainly increased dopamine among monoamines and their metabolites(norepinephrine, dopamine, DOPAC, HVA, serotonin, 5-HIAA) significantly in 4 parts of rat's brain above-mentioned. Calculated by turnover ratio formulae of monoamine, chunwangboshimdan has more results than Imipramine. These results suggest that chunwangboshimdan has antidepressant effect that is related with the increase of monoamines by suppressing their metabolism as its mechanism.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.321-329
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• 2013

Rodents exposed to a 15-min pretest swim in the forced swimming test (FST) exhibit prolonged immobility in a subsequent 5-min test swim, and antidepressant treatment before the test swim reduces immobility. At present, neuronal circuits recruited by antidepressant before the test swim remain unclear, and also less is known about whether antidepressants with different mechanisms of action could influence neural circuits differentially. To reveal the neural circuits associated with antidepressant effect in the FST, we injected desipramine or citalopram 0.5 h, 19 h, and 23 h after the pretest swim and observed changes in c-Fos expression in rats before the test swim, namely 24 h after the pretest swim. Desipramine treatment alone in the absence of pretest swim was without effect, whereas citalopram treatment alone significantly increased the number of c-Fos-like immunoreactive cells in the central nucleus of the amygdala and bed nucleus of the stria terminalis, where this pattern of increase appears to be maintained after the pretest swim. Both desipramine and citalopram treatment after the pretest swim significantly increased the number of c-Fos-like immunoreactive cells in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim. These results suggest that citalopram may affect c-Fos expression in the central nucleus of the amygdala and bed nucleus of the stria terminalis distinctively and raise the possibility that upregulation of c-Fos in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim may be one of the probable common mechanisms underlying antidepressant effect in the FST.

• Journal of Acupuncture Research
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• v.24 no.6
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• pp.29-36
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• 2007

Electroacupuncture(EA) is known to affect various autonomic functions such as blood pressure regulation, immune modulation and the improvement of disorders concerning autonomic functions. The aim of the present study was to establish whether EA has an immune-enhancing effect. ICR mice weighing 20 to 25g were divided into four groups: Group I(n=6), blank; Group II(n=6), control; Group III(Zusanli, n=6), low frequency-EA(10Hz of electrical stimulation), and Group IV(Zusanli, n=6), high frequency-EA (100Hz of electrical stimulation). For this study, we investigated expressions of spleen heat shock protein (HSP)70, HSP90 and secretions of cytokines. A Forced Swimming Test(FST) was performed as a model of activity test in mice. After three days of the FST, 10Hz EA($114.8{\pm}7.27s$) and 100Hz EA($147.5{\pm}1.29s$) immobility time significantly decreased compared with the control group($157.2{\pm}1.48s$). After seven days, 10Hz EA($124{\pm}1s$) and 100Hz EA($141{\pm}4.24s$) also significantly decreased immobility time compared with the control group($168{\pm}7.93s$). 10Hz EA and 100Hz EA increased the expression of HSP70 but did not change that of HSP90. 100Hz EA increased secretions of IL-6 and IL-12 compared with the control group however, 10Hz EA failed to change those of IL-6 and IL-12. The present results suggest that EA may be useful for down-regulated immune diseases.