• 대한기계학회논문집B
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• 제25권10호
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• pp.1408-1416
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• 2001

Mean flow fields in the near wake of a square cylinder have been studied experimentally using a Particle Image Velocimetry (PIV). Ensemble-averaged velocity fields are successfully measured fur the square cylinder wake including the reverse flow region which arises many difficulties in accurate measurement by using conventional techniques, Experiments are performed at two free stream velocities of U$\_$$\infty$/ = 1.27m/s and 3.03m/s. The corresponding Reynolds numbers based on the free-stream velocity and cylinder diameter are 1600 and 3900, respectively. The intensity of free-stream turbulence is less than 1%, the blockage ratio (D/H) is 6.6% and the aspect ratio (W/D) is 40. The effect of Reynolds number on the near wake of a square cylinder has been investigated by the global mean velocity and instantaneous velocity fields. The most striking feature is that the length of the recirculating region increases with increasing Reynolds number, which turns out totally reverse trend compared with those observed in the circular cylinder wake at the same range of Reynolds number. Fer the case of higher Reynolds number, the mean velocity data agree well with those of relevant existing data obtained at much higher Reynolds numbers, which reflects the general aspect of sharp-edged bluff body wake.

• 동의생리병리학회지
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• 제20권3호
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• pp.516-521
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• 2006

The following conclusions are drawn from Hyungsang medicinal review on th globs hystericus through Donguibogam and other literatures. The globs hystericus appears in the throat and the epigastric region. It is a subjective sensation as if a plum pit is stick in the throat and is compressed, usually ac companied by stuffiness in chest, depression, nausea, and hiccup. But the throat is not marked with redness and swelling. Because Gi stagnation due to seven emotions is the main cause, the globs hystericus is usually followed by Seven Gi injuries, Pain and depressive syndrome due to disorder of Gi, palpitation due to fright, continuous violent palpitation, Gi phlegm, precordial pain with palpitation, epigastric pain due to seven emotions, cough and dyspnea due to disorder of Gi, and six kinds of stagnations. When head and body or chest and abdomen is compared to heaven and earth, the blockage of Gi between heaven and earth is common to the persons with the following charcteristics in Hyungsang; Dam type rather than Bankwang type, Gi type and Shin type rather than deer type and fish type, Taeum and Yangmyeong meridian types out of six meridian types, manly women, womanly man, too long or short neck, and signs of stagnation between the eyebrows. The globus hystericus needs, distinguishing from aphonia, acute tonsilitis, goiter, and pectorial pain with stuffiness. The affected area of aphonia and acute tonsilitis is the throat but they are not cause by the disturbance of seven emotions. Goiter can be distinguished by the changes in the appearance of neck. Even though the symptoms are similar, globus hystericus is caused by the stagnation of Gi, but the pectorial pain with stuffiness, by the insufficiency of the Heart blood. The general prescriptions are Chilgitang, Sachiltang, Gamisachiltang, Gamiijintang, and Sinihwan.

• Journal of Audiology & Otology
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• 제24권1호
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• pp.10-16
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• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• 대한청각학회지
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• 제24권1호
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• pp.10-16
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• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• BMB Reports
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• 제56권5호
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• pp.314-319
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• 2023

Sepsis is a life-threatening multi-organ dysfunction with high mortality caused by the body's improper response to microbial infection. No new effective therapy has emerged that can adequately treat patients with sepsis. We previously demonstrated that interferon-β (IFN-β) protects against sepsis via sirtuin 1-(SIRT1)-mediated immunosuppression. Another study also reported its significant protective effect against acute respiratory distress syndrome, a complication of severe sepsis, in human patients. However, the IFN-β effect cannot solely be explained by SIRT1-mediated immunosuppression, since sepsis induces immunosuppression in patients. Here, we show that IFN-β, in combination with nicotinamide riboside (NR), alleviates sepsis by blocking endothelial damage via SIRT1 activation. IFN-β plus NR protected against cecal ligation puncture-(CLP)-induced sepsis in wild-type mice, but not in endothelial cell-specific Sirt1 knockout (EC-Sirt1 KO) mice. IFN-β upregulated SIRT1 protein expression in endothelial cells in a protein synthesis-independent manner. IFN-β plus NR reduced the CLP-induced increase in in vivo endothelial permeability in wild-type, but not EC-Sirt1 KO mice. IFN-β plus NR suppressed lipopolysaccharide-induced up-regulation of heparinase 1, but the effect was abolished by Sirt1 knockdown in endothelial cells. Our results suggest that IFN-β plus NR protects against endothelial damage during sepsis via activation of the SIRT1/heparinase 1 pathway.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.85-92
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• 2002

When the United Nation classified as Korea is the one of the water deficit country. The consensus was made that the water is the one of the precious national resources. Government increases their R/D budget trying to get more clean water bodies. For instances, 'Sustainable Water Resources Development' project is the one of major title in '21 Century Frontier Research project and there are several small research projects are undergoing by the Ministry of Agriculture and KARICO. However, when the environmental preservation issue has been get more emphasis, construction of the Surface Dam met the blockage from the environmentalists due to the problem of the their water buried area. Since the most fitting site for surface dam had been used in the past, some engineer move their focus on modification of the existing Dam's height to enlarge its capacity or dredging the bottom of the reservoir recently However dredging evoke water quality problem in return by accumulated materials at the bottom. Last year the Dong Gang Dam plan has been canceled by environmental problem in water buried area of the reservoir. With the point of this view, ground water gets more focus for the one of the useful alternative for clean water bodies. Underground dam technique which had widely applied once in the early nineteen eighties by the KARICO and attenuated due to engineering insufficiency. The technique is newly studied with the advanced engineering technique. Still groundwater usage rate in Korea is much lower comparing with the advanced countries and has many rooms to develop. Wells, under ground dam and radial collector wells are typical facilities up to now. There is little application in Korea for the Recharge Dam, which had been widely used in the advanced countries. The Recharge Dam is technique to conjunct surface water and groundwater body together, This technique had developed to increase groundwater recharge at the beginning This research is the result of the study on the possibility of the development of the new technology, Groundwater Reservoir' which was modified from Recharge Dam. Groundwater Reservoir is like a deep artificial lakes trenched in hard rock aquifer to get groundwater. The advantage of the Groundwater Reservoir is followings 1) It can be developed at the plains area, not in the deep valley 2) Huge water body can be developed without dam 3) Small buried area comparing surface water dam makes the least environmental effect. 4) Trenching cost can be substitute by the income of the selling rock debris 5) Outfit of the reservoir can be modified to match with the site prospect 6) Rock debris can be used as constructing materials 7) It can be used as groundwater recharge system when the heavy rains comes 8) The reservoir looks like scenery lake with huge clean water bodies.

• 동양고전연구
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• 제73호
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• pp.281-302
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• 2018

순자철학에서 마음의 역할은 매우 중요하다. 순자에게 도란 정치의 영원하고 항구적인 법칙인데, 그 도는 마음이 주재한다. 그런데 마음은 사유 활동과 사물에 대한 인식 기관이다. 그럼에도 불구하고 마음은 조절되지 않으면 안 되는 욕구를 지닌 몸이다. 또 한편으로 마음은 인식 측면에서 저장과 비움, 움직임과 고요함, 하나에 또 하나의 두 갈래의 중층적 양상을 지닌다. 그런 마음의 꾀인 심술(心術)에는 여러 가지 가림의 폐단이 있다. 이런 점에서 마음을 닦고 기르기가 요구된다. 순자는 치기양심(治氣養心), 몸 차원의 기를 다스리고 사유 기능의 마음을 기르는 수양을 제안하는데, 맹자가 도덕심 함양을 위한 욕심 줄이기나 호연지기 기르기를 중시했다면, 순자는 신체기관을 거느리고 공적인 인식을 위해 마음 기르기를 요청하였다. 순자의 생각에 마음에는 인식 측면에서 마치 그릇의 물이 만드는 수경(水鏡)과 같은 면모가 있다. 그래서 물에 내재하는 찌꺼기를 가라앉히지 않으면 사물의 이미지를 제대로 반영할 수 없다. 이런 맥락에서 마음의 폐단을 제거하야야 하며, 그런 차원에서 수양 또한 필요하다. 궁극적으로 국가의 안정을 위한 이치를 밝히고 떳떳한 도리를 회복하기 위해 마음은 중층적(重層的)이어서는 안 되며, 이에 수양의 문제가 대두된다. 이 논문은, 이런 문제의식에서, 순자철학에 나타난 마음의 의의, 그 중층적 양태, 그리고 수양의 필요성에 대하여 접근한다.