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Doing a Research on 『East and West Medicine Research Society Monthly View』 (『동서의학연구회월보(東西醫學硏究會月報)』 연구)

  • Jung, Ji Hun
    • The Journal of Korean Medical History
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    • v.15 no.1
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    • pp.199-212
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    • 2002
  • "East and West Medicine Research Society Monthly View" was published 7 times to revive and develope the Eastern medicine that was in downward trend with an "review the old and learn the new" attitude to unite the East and West medicine. This magazine was lead by the East and West Medicine Research Society and therefore an academic magazine. Its contents mostly consist of lecture type serials. This is because the purpose of the magazine was to reeducate physicians of the Chinese school or to educate the people who had purpose on medicine. The contents of "East and West Medicine Research Society Monthly View" has many serials on various subjects such as Eastern Medicine, Western Medicine, East and West Medicine, and SaSang medicine. Puting in articles about hygiene to put in many writings about living health shows the effort in trying to treat epidemics with Korean Medicine.

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Smouldering Combustion of Cellulose Insulation and Its Transition to Flaming Combustion (석면 대체용 셀룰로오스 단열재의 연소전이에 관한 연구)

  • Kim, Hong;Kim, Ki-Hwan
    • Journal of the Korean Society of Safety
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    • v.7 no.3
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    • pp.14-21
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    • 1992
  • The smouldering combustion of cellulose insulation treated with boric acid-borax-alum as combustion retardants are examined by Candle type combustibility tester. This sequence was examined quantitatively for longitudinal cylinder bed of cellulose insulation. Two configuration are possible, downward and upward smoulder spread ; both were investigated exprimentally. The smoulder spread velocity of cellulose insulation was 2.5cm/s -5.0cm/s in smoulder region. As results of critical oxygen content measurement, the effectiveness of alum as third combustion retardant are acceptable for flaming retardant effect. The phenomena of combustion transition are governed by quantity of commbustible gas generation In heating zone of cellulose insulation. The critial oxygen content are decreased with the increase of gas flow rate.

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Characteristics Analysis and Test of a Voice-Coil-Type LOA Considering the Push/pull Effects (Push/Pull Effect를 고려한 보이스코일형 LOA의 특성해석 및 시험)

  • Jang, S.M.;Jeong, S.S.;Park, H.C.;Moon, S.J.;Park, C.I.;Chung, T.Y.
    • Proceedings of the KIEE Conference
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    • 1998.07a
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    • pp.275-277
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    • 1998
  • The effect of the coil flux, so called "push/pull effect", is to shift the airgap flux density variation due to the magnet alone by a certain amount. Thrust therefore is shift downward or upward. The push/pull effect was presented through the FEM analysis and static tests. We compared with the thrust obtained through the FEM analysis and static tests.

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FLUID-GRANULE MIXED FLOIW DOWNSTREAM OF SCOUR HOLE AT OUTLET OF HYDRAULIC STRUCTURE

  • Kim, Jin-Hong;Shim, Myung-Pil;Kim, Kyung-Sub
    • Water Engineering Research
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    • v.3 no.3
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    • pp.155-162
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    • 2002
  • This study presents the theoretical approach for volume concentration, velocity profile, and granular discharge on the fluid-granule mixed flow downstream of the scour hole at the outlet of the hydraulic structure. Concept of dilatant model was applied for the stress-strain relationships of fluid-granule mixed flow since the flow downstream of the scour hole corresponds to debris flow, where momentum transfers through particle collisions. Mathematical formulations were derived using momentum equation and stress-strain relation of the fluid-granule mixture. Velocity profile under the assumption of uniform concentration over flowing layer showed the downward convex type. Deposition angle of downstream hump was found to be a function of an upstream slope angle, a dynamic friction angle and a volume concentration irrespective of flow itself, Granular discharge and the overflow depth were obtained with given values of inflow rates. Experimental results showed relatively good agreements with theoretical ones.

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EXPERIMENTAL STUDY OF CRITICAL HEAT FLUX WITH ALUMINA-WATER NANOFLUIDS IN DOWNWARD-FACING CHANNELS FOR IN-VESSEL RETENTION APPLICATIONS

  • Dewitt, G.;Mckrell, T.;Buongiorno, J.;Hu, L.W.;Park, R.J.
    • Nuclear Engineering and Technology
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    • v.45 no.3
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    • pp.335-346
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    • 2013
  • The Critical Heat Flux (CHF) of water with dispersed alumina nanoparticles was measured for the geometry and flow conditions relevant to the In-Vessel Retention (IVR) situation which can occur during core melting sequences in certain advanced Light Water Reactors (LWRs). CHF measurements were conducted in a flow boiling loop featuring a test section designed to be thermal-hydraulically similar to the vessel/insulation gap in the Westinghouse AP1000 plant. The effects of orientation angle, pressure, mass flux, fluid type, boiling time, surface material, and surface state were investigated. Results for water-based nanofluids with alumina nanoparticles (0.001% by volume) on stainless steel surface indicate an average 70% CHF enhancement with a range of 17% to 108% depending on the specific flow conditions expected for IVR. Experiments also indicate that only about thirty minutes of boiling time (which drives nanoparticle deposition) are needed to obtain substantial CHF enhancement with nanofluids.

A study on the unfolding length of Z-bending machining using thin plate (박판을 이용한 Z-굽힘 가공의 전개 길이에 관한 연구)

  • Park, Yong-Sun;Choi, Kye-Kwang
    • Design & Manufacturing
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    • v.15 no.3
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    • pp.19-25
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    • 2021
  • The bending process of a press die is to bend a flat blank to the required angle. There are V-bending, U-bending, Z-bending, O-bending etc. for bending processing, and the basic principle of calculating the unfolding length of die processing is used as the neutral plane length. Since the constant of the length value of the neutral surface is different depending on the type of bending, it is impossible to accurately calculate it. In particular, Z-bending processing is performed twice, and it is set on the upper and lower surfaces of the blank, and bending processing occurs at the same time as the upward and downward bending, and the elongation of the material occurs and the material increases. It is not possible to check with the calculated value, and it occurs in many cases where the mold is modified after start-up. This study aims to minimize die modification by developing a formula to calculate the development length of Z-bend.

Experimental Study on Flow Change at Downstream of Stepped Drop Structure (계단형 낙차공 하류 흐름변화에 대한 실험연구)

  • Yeo, Hong-Koo;Kang, Joon-Gu;Choi, Nam-Jeong;Kim, Sung-Jung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1889-1893
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    • 2008
  • 본 연구에서는 완경사 계단형 낙차공에서 하류수심 변화에 따른 도수 형태의 변화와 WTF 흐름 특성에 대한 분석을 수행하였다. 일정한 유량에서 하류수위를 증가시키면 도수 형태가 달라지는데 특히 계단 끝단에서 완전도수, 잠김도수(B점프), downward curved jet, upward curved jet, wave type flow(WTF)가 차례로 나타났다. 잠김도수에서는 표면 롤러 현상이 관찰되었고 curved jet에서는 큰 유속 감세 없이 파가 하류까지 전달되었다. WTF에서는 사류흐름이 바닥 recirculation 구역의 영향으로 변형되면서 wave 형태의 도수를 발생시켰다. 하류수위를 점점 증가 시키면 도수의 발생 위치가 계단 위쪽으로 이동하며 잠김도수와 WTF가 번갈아가며 발생하였다. 하류수위가 높아질수록 도수의 규모는 작아졌으며 표면 롤러도 미약해지는 경향을 보였다. 세 가지 유량조건에 따른 WTF의 규모를 비교한 결과 유량이 증가할수록 WTF의 크기가 증가하였으며 무차원화한 WTF의 형상은 거의 비슷한 것으로 나타났다. 계단형 낙차공은 기존낙차공에서 발생하는 도수와 달리 WTF가 발생되므로 이에 대한 분석이 필요하다. WTF가 발생하는 구간의 수위는 하류수위보다 높아지기 때문에 하천 설계 시 하천 접합부의 조건(구수부지설치, 제방설치 등)에 따라 wave의 높이가 설계의 중요 인자로 고려되어야 할 것이다. WTF는 지금까지의 계단형 낙차공 설계 시 고려되지 못한 부분으로서 차후에 계단형 구조물 또는 계단식 변형 구조물 설계 시 주요 자료로 활용 될 것이다.

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The relationship between malocclusion and menarcheal age, and its secular trend for Korean women

  • Choi, Yoon-Jeong;Chung, Choo-Ryung;Kim, Kyung-Ho
    • The korean journal of orthodontics
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    • v.42 no.1
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    • pp.11-16
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    • 2012
  • Objective: This study aimed to evaluate the mean age of menarche, its secular trend in Korean women, and the relationship between malocclusion and the rate of skeletal maturation, as defined by menarcheal age. Methods: We retrospectively collected data on menarcheal age from 931 Korean women born during 1961 - 1997. Subjects were divided by the malocclusion type and birth-year decade into 3 and 4 groups, respectively. The mean menarcheal age for each group was determined, and one-way ANOVA was performed for intergroup comparison (p = 0.05). Two-way ANOVA was also performed to compare all the 12 subgroups (p = 0.05). Results: The mean age of menarche was 12.82 years for Korean women born during 1961 - 1997. A distinct downward secular trend of menarcheal age was noticed (p < 0.05). For the birth-year decade 1961 - 1970, the Class III malocclusion group showed earlier onset of menarche than the other malocclusion groups (p < 0.05), but the other birth-year groups did not show any significant difference in the type of malocclusion (p > 0.05). Conclusions: A positive secular trend towards earlier menarche exists among Korean women. Malocclusion does not show any significant relationship with the rate of skeletal maturation, as defined by menarcheal age.

Correction of post-traumatic anterior open bite by injection of botulinum toxin type A into the anterior belly of the digastric muscle: case report

  • Seok, Hyun;Park, Yong-Tae;Kim, Seong-Gon;Park, Young-Wook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.39 no.4
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    • pp.188-192
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    • 2013
  • Post-traumatic anterior open bite can occur as a result of broken balance among the masticatory muscles. The superior hyoid muscle group retracts the mandible downward and contributes to the anterior open bite. Denervation of the digastric muscle by injection of botulinum toxin type A (BTX-A) can reduce the power of the digastric muscle and help to resolve the post-traumatic anterior open bite. A patient with a bilateral angle fracture had an anterior open bite even after undergoing three operations under general anesthesia and rubber traction. Although the open bite showed some improvement by the repeated operation, the occlusion was still unstable six weeks after the initial treatment. To eliminate the residual anterior open bite, BTX-A was injected into the anterior belly of the digastric muscle. Following injection of BTX-A, the anterior open bite showed immediate improvement. Complication and relapse were not observed during follow-up. Long-standing post-traumatic open bite could be successfully corrected by injection of BTX-A into the anterior belly of the digastric muscle without complication.

Development of new electrical leakage detection system for waste landfil (위생매립지 누출검지 및 누출위치 파악을 위한 전극배치시스템 개발)

  • Han, Sang-Jae;Shin, Hyun-Young;Jung, Jae-Hyun;Kim, Soo-Sam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.242-250
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    • 2008
  • Lining systems are used for two purpose in landfills : as covers to minimize leachate generation and surface water contamination by providing a barrier from precipitation and other percolating waters, and as containment liners to contain leachate and minimize its downward migration into underlying groundwater. So identifying leaks in landfill liners is an essential part of waste management. There are many leakage detection systems to monitor and seek leakage location, such as two electrode method, electrode grid method, diffusion hoses, capacitance sensors and tracers sensing cables. However, most of them can be applied in the new landfill construction sites because sensors must be installed prior to work. This paper presents a new type of leakage detection system, so called fence type electrode arrangement system, to monitor leakage and to seek leakage location in working landfill as well as new landfill. This system is based on the measurement of an electrical current flowing through leakage point. Series of laboratory tests are performed to investigate an availability of this system and this paper present some of these results.

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