• Title/Summary/Keyword: Cold flow

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A Study of Ginger Herbal Pharmacopuncture for Practical Application (생강 약침의 임상적 활용을 위한 고찰)

  • Lee, Chae-Woo;Lee, Byung-Hoon;Youn, Hyoun-Min
    • Journal of Pharmacopuncture
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    • v.12 no.1
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    • pp.43-51
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    • 2009
  • Objective : The purpose of this study is to present the standard for practical application of ginger herbal pharmacopuncture Material and Methods : We refer to ancient literatures and the recent papers for ginger. Conclusions : The following results have been obtained 1. The effect of ginger(Zingiber officinale Roscoe) is to "release exterior", "balance nutrient & defensive qi", "resolve phlegm", "arrest coughing", "warm the lungs". So ginger herbal pharmacopuncture can be applied to treating fever, chilling sign, headchae, snuffle and gasping cough due to cold affection and treating the symptoms like sputum and asthma that be revealed by pulmonary disease. 2. The effect of ginger is to "warm spleen and stomach", "arrest vomiting" "promote normal flow of water". So ginger herbal pharmacopuncture can be applied to treating nausea, vomiting, abdominal distension and diarrhea due to phlegm & dampness and treating edema. 3. The effect of ginger is to eliminate blood stasis. So ginger herbal pharmacopuncture can be applied to treating contusion, blood stasis, sprain and gynecologic disease. 4. Ginger can treat myalgia and pain due to wind-damp and have anti-inflammatory effect in pharmacology. So ginger herbal pharmacopuncture can be applied to treating disease of joint, ligament and muscle. 5. Ginger can resolve phlegm and resuscitate. So ginger herbal pharmacopuncture can be applied to treating unconsciousness. But, treating incipient cardiovascular accident, it needs to call your special attention to the danger of blood pressure increase. 6. In pharmacology, ginger is effective for antitumor, antioxidant effects and activating immunocyte. So ginger herbal pharmacopuncture can be applied to treating broadly varieties of tumor and allergic disease.

The Classification of Spatial Patterns Considering Formation Parameters of Urban Climate - The case of Changwon city, South Korea - (도시기후 형성 요소를 고려한 공간유형 분류 -창원시를 대상으로 -)

  • Song, Bonggeun;Park, Kyunghun
    • Journal of Environmental Impact Assessment
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    • v.20 no.3
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    • pp.299-311
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    • 2011
  • The objective of this paper is to present a methodology for the classification of spatial patterns considering the parameters of urban form which play a significant role in the formation of the urban climate. The urban morphological parameters, i.e. building coverage, impervious pavement, vegetation, water, farmland and landuse types were used to classify the spatial patterns by a K-means cluster analysis. And the presented methodology was applied on Changwon city, South Korea. According to the results of cluster analysis, the total spatial patterns were classified as 24 patterns. First of all, The spatial patterns(A-1, A-2, A-3, B-1, B-2, B-3, C-1, C-2, C-3, D-1, D-2, D-3, E-1, E-2, E-3, F-1, F-2, F-3, G-1, G-2, G-3), which distributed in the rural area and the suburban area, can have the positive impacts of cold air generation and wind corridor on an urban climate environment, were distributed in the rural area. On the other hand, the spatial patterns of the downtown area including A-4, B-4, C-4 and D-4 are expected to have the negative impacts on urban climate owing to the of artificial heat emission or the wind flow obstruction. Finally, it will require the future research to analysis the climatic properties according to the same spatial patterns by the field survey.

Necessary Conditions for Optimal Ventilation of Small Negative Pressure Ventilating Piglet House with Corridor and Attic for Preheating (소규모 복도-더그매 예열 음압환기방식 무창자돈사의 최적 환기 요건에 관한 연구)

  • Lee, Seung-Joo;Chang, Dong-Il;Hwang, Seon-Ho;Gutierrez, Winson M.;Chang, Hong-Hee
    • Journal of Biosystems Engineering
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    • v.35 no.6
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    • pp.434-442
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    • 2010
  • This study was carried out to determine necessary conditions for optimal ventilation of small windowless piglet house (4.0 (W) $\times$ 11.0 (L) $\times$ 2.6(H) m) with corridor and attic for preheating using CFD (Computational Fluid Dynamics) simulation. The experimental weaning piglet house was consisted of a corridor, an attic, 4 rooms (3.0 (W) $\times$ 2.75(L) m), 3 fences (0.7(H) m), 5 air inlets and 2 exhaust fans (0.4 (D) m) and simulated using CFD code, FLUENT. The simulation results for the experimental weaning piglet house showed that each room was uniformly ventilated under all the experimental conditions and air velocities at 0.1 m above floor are less than 0.15 m/s for 0.75 m/s and 1.0 m/s of air inlet velocity but 0.61 m/s for 1.25 m/s. The simulation results are similar to the measured results. Considering the air flow pattern, ventilating efficiency, air velocity at 0.1 m above floor and cold stress of weaning piglets and so on, the optimum velocity of air inlet might be 1.0 m/s.

Development of a PTC Heater for Supplementary Heating in a Diesel Vehicle (디젤 차량의 보조 난방을 위한 PTC 히터 개발)

  • Shin, Yoon Hyuk;Kim, Sung Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.666-671
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    • 2014
  • Using positive temperature coefficient (PTC) heater as supplementary heating for diesel engine vehicles with low heat source is a good method to enhance the heating performance during cold start. In this study, the PTC elements were made by using screen printing process for forming ohmic contact layer, and prototype of PTC heater was designed and made for a diesel engine vehicle. In process of designing the PTC heater, the thermal flow analysis of PTC element modules was conducted for verifying the effect of the shapes of contact surface between each of the components (cooling fin, insulator, ceramic element). We also investigated the performance characteristic (heating capacity, energy efficiency, pressure drop) of the PTC heater through the experiments. Therefore, the experimental results indicated that prototype of PTC heater had satisfactory performance. This study will be basis for improving the manufacturing process and increasing the performance of the PTC element and heater.

Numerical study of a turbulent plane jet under the pressure gradient in the transverse direction (진행축에 수직방향 압력구배를 받는 난류 평면제트의 수치적 연구)

  • 최문창;최도형
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.5
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    • pp.1150-1157
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    • 1988
  • Two-dimensional turbulent plane jet which is under the pressure gradient in the transverse direction is studied numerically. Full Navier-Stokes equations are used to correctly account for the pressure variation in the transverse direction. Using the standard k-.epsilon. turbulence model as a closure relationship, a time marching procedure gives the velocity field. The temperature fields are obtained for two different cases : (1) Hot jet is issued into the cold still air, and (2) Hot jet is issued into the surrounding across which exists a temperature difference. The velocity and temperature fields along with other flow and heat-transfer characteristics for two different pressure gradients are presented. A simple formula that relates the jet trajectory to the pressure gradient is also proposed. The mass flux in the longitudinal direction and the jet halfwidth seem insensitive to the pressure gradient. However, the pressure gradient increases the heat flux in the longitudinal direction as well as in the transverse direction.

A Translation Study on the First Volume of "Uihakdokseogi (醫學讀書記)"(I) ("의학독서기(醫學讀書記).권상(卷上)"에 대(對)한 번역연구(飜譯硏究)(I))

  • Im, E-Bin;Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.21 no.1
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    • pp.183-203
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    • 2008
  • "Uihakdokseogi(醫學讀書記)" is a casual work which mentions Ujaekyeong(尤在涇)'s thoughts on various problems found through extensive studying or in practice. The book does not focus on a single topic, thus the spectrum of the work is broad and is filled with problems which would interest most medical professionals. The major contents of the first volume of "Uihakdokseogi(醫學讀書記)" include differences of view on health preservation, the Five Circuit Phases[五運] and Six Atmospheric Influences[六氣], diseases, and the "Naegyeong(內經)", mentions on errors in transcription , and the gap between certain contents in "Yeongchu(靈樞)" and "Somun(素問)". U[尤在涇] asserts that Eum and Yang(陰陽) in a human should be in harmony as is the Gi(氣) of the sky and earth[天地] is, and that one should live according to the Gi(氣) of the four seasons to live a healthy life. He does not vary largely from the context of other writers on the matter of the Five Circuit Phases [五運] and Six Atmospheric Influences[六氣], and focuses on the concepts of predominant Gi[主氣], guest Gi[客氣], corresponding years[天符] , correlating years[歲會], and Taeeul corresponding years[太乙天符]. He mentions causes, symptoms, and treatments of various diseases such as cough due to asthenia of the viscera, stagnation of Yang(陽), stagnation of Eum(陰), abscess of the stomach, hard abscess of the intestines, upper emaciation, edema of the limbs, inability to raise the limbs, broken thigh, turbid fluid, inversion of Gi(氣) flow, sudden onset of fainting with cold extremities, diarrhea due to disorder of Gi(氣), and malaria. U[尤在涇] also points out faults of "Classic of Acupuncture and Moxibustion[甲乙經]" in the understanding of "Naegyeong(內經)".

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Probabilistic Approach for Fighter Inlet Hammershock Design Pressure (전투기 흡입구 해머쇼크 설계압력에 대한 확률론적 접근법)

  • Bae, Hyo-gil;Lee, Hoon Sik;Kim, Yun-mi;Jeong, In Myon;Lee, SangHyo;Cho, Dae-yeong
    • Journal of Aerospace System Engineering
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    • v.13 no.5
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    • pp.72-78
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    • 2019
  • Inlet hammershock is the critical loads condition for designing the inlet duct structure of a fighter. The sudden flow reduction in engine compressor causes inlet hammershock with high pressure. The traditional method was used to combine extreme conditions (maximum speed, sea level altitude, and cold day) to analyze this compression wave inlet hammershock pressure. However, after the 90s there have been papers that presented the probabilistic approach for the inlet hammershock to achieve the appropriate design pressure. This study shows how to analyze the inlet hammershock pressure by making practical use of the Republic of Korea Air Force real flight usage data under probabilistic approach and then analyze approximately 30% decreased inlet hammershock pressure compared with the traditional valve.

Spray Characteristics of Swirl-coaxial Injector According to the Recess Length and Injection Pressure Variation (리세스 길이 및 분사압력 변이에 따른 스월 동축형 인젝터의 분무특성)

  • Bae, Seong Hun;Kwon, Oh Chae;Kim, Jeong Soo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.20 no.4
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    • pp.68-76
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    • 2016
  • This research is carried out for the performance evaluation of the injector that is one of the critical components of bipropellant-rocket-engine. Spray characteristics are investigated in detail according to the recess length and injection pressure on the swirl-coaxial-injector using gaseous methane and liquid oxygen as propellants. A visualization is conducted by the Schlieren photography that is composed of a light source, concave mirrors, knife, and high-speed-camera. A hollow-cone-shape is identified in the liquid spray that is spread only by inner injector and the spray angle is decreased due to the diminution of swirl strength in accordance with the increase of the length of injector orifice. When the injector sprays the liquid through the inner injector with the aid of gas through the outer injector, the spray angle in external mixing region tends to increase with rise of the recess length, while in internal mixing region, it is decreased. It is also confirmed that the same tendency of the spray angle with recess length appears irrespective of the injection pressure of liquid spray.

Spray Characteristics of Liquid Jets in Acoustically-Forced Crossflows (음향가진된 횡단류 유동장 내 액체제트의 분무특성)

  • Song, Yoonho;Hwang, Donghyun;Ahn, Kyubok
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.2
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    • pp.1-10
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    • 2018
  • This study investigated the acoustic forcing effects on the liquid column breakup length and the trajectory of liquid jets in crossflows. Cold-flow tests with a single hole circular nozzle injector were carried out by changing the injection pressure and acoustic forcing amplitude. Additionally, spray images were obtained at 12 phase angles to investigate the influence of the phage angle. The results revealed that the liquid column breakup lengths generally decreased under the acoustic forcing conditions, in comparison to those under the non-acoustic forcing conditions. However, they were not affected by the variation in the phase angles. On the contrary, it was found that the acoustic forcing hardly influenced the liquid column trajectories.

Pressure Control of Staged Combustion Liquid Rocket Engine (다단연소사이클 액체 로켓엔진의 압력제어에 대한 연구)

  • Hwang, Changhwan;Lee, Kwangjin;Woo, Seongphil;Im, Ji-Hyuk;Jeon, Junsu;Lee, Jungho;Yoo, Byungil;Han, Yeoungmin
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.4
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    • pp.18-23
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    • 2018
  • For the control of pre-burner combustion pressure, the open angle of the TTR (Throttle for Thrust Regulation) valve was varied from $143^{\circ}$ to $185^{\circ}$ while testing cold flow, ignition, and combustion. The major performance variables of rocket engines and hydraulic performance of the TTR valve regarding the open angle were verified. However, the controllability of pre-burner combustion pressure was not verified due to the limitations of the test. Comprehensive research will be done after addressing these problems.