• 제목/요약/키워드: E/Y ratio

검색결과 4,725건 처리시간 0.031초

비원형 Effervescent Type 이유체노즐의 Discharge Coefficient에 관한 실험적 연구 (An Experimental Study of Discharge Coefficient with Non-Circular Effervescent Type Twin-fluid Nozzle)

  • 이상지;박형선;홍정구
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2017년도 제48회 춘계학술대회논문집
    • /
    • pp.682-685
    • /
    • 2017
  • 본 연구는 비원형 Effervescent Type 이유체 노즐의 분사 특성을 조사하기 위한 실험적 연구를 수행하였다. 이를 위해 거의 동일한 노즐 출구 면적으로 가공한 2종류의 비원형 노즐 (E1, E2)과 1종류의 원형 노즐 (C)을 대상으로 비교 실험을 진행하였다. 이때 노즐에 장착된 Aerorator는 노즐 출구 면적과의 Aspect Ratio를 맞추기 위해 지름이 다른 3종류를 사용하였다. 따라서 각 노즐마다 3가지의 Aspect Ratio에 따라 3번의 실험을 진행하였으며, 전체 총 9종의 실험이 진행되었다. 실험은 Liquid의 유량을 고정시킨 후, 유입되는 Air의 양을 제어하며 진행하였으며, 노즐 내부 압력과 액적의 크기 (SMD)를 측정하고 노즐에서 분사 이미지를 촬영하였다. 이를 통해 3종의 노즐의 유량 계수를 압력 분무방정식과 Jedelsky 방정식을 비교 계산하였고, Jedelsky 방정식이 약 4배 정도 더 큰 값을 갖는 것을 확인하였다. 노즐에서 분사되는 SMD는 원형보다 비원형에서 더 작은 값을 갖는 것으로 나타났으며, 이는 유량 계수 값의 차이 의해 야기된 것으로 예상된다.

  • PDF

Adaptive Diversity of Echinochloa Species to Osmotic Stress

  • Park, Seon-Ju;Yu, Hye-Jin;Yook, Min-Jung;Kim, Do-Soon
    • Weed & Turfgrass Science
    • /
    • 제5권4호
    • /
    • pp.181-186
    • /
    • 2016
  • Three Echinochloa species inhabit various crop fields with different soil moisture conditions. Therefore, a growthpouch test was conducted to investigate adaptive diversity of six Echinochloa species, three from Korea and three from USA, toosmotic stress by assessing shoot and root growths. Echinochloa crus-galli var. praticola showed the greatest tolerance to osmoticstress in both root ($GR_{50}=1316.3g\;PEG\;L^{-1}$) and shoot ($GR_{50}=212.2g\;PEG\;L^{-1}$) growths, while Korean E. oryzicola was mostsensitive to osmotic stress in both root ($GR_{50}=116g\;PEG\;L^{-1}$) and shoot ($GR_{50}=126.2g\;PEG\;L^{-1}$) growths. Root to shoot (R/S) ratioof Echinochloa crus-galli var. praticola increased with increasing osmotic stress, while that of Korean E. oryzicola decreased, suggestingthat R/S ratio is closely related to osmotic stress tolerance in Echinochloa species. Our results clearly demonstrate that E. crus-galli var.praticola maintains high R/S ratio even under high osmotic stress, which enables this species to well adapt to dry upland condition. Incontrast, while E. oryzicola fails to maintain sufficiently high R/S ratio, resulting in poor adaptability to dry upland condition.

톱다리개미허리노린재의 집합페로몬에 의한 노린재류의 난기생봉 Ooencyrtus nezarae의 유인과 발생소장 (Seasonal Occurrence and Attraction of Egg Parasitoid of Bugs, Ooencyrtus nezarae, to Aggregation Pheromone of Bean Bug, Riptortus clavatus)

  • 허완;박정규
    • 한국응용곤충학회지
    • /
    • 제44권2호
    • /
    • pp.131-137
    • /
    • 2005
  • 경남진주의 콩포장과 대학 캠퍼스에서 톱다리개미허리노린재의 집합페로몬을 사용하여 난기 생봉인 Ooencyrtus nerarae(Hymenoptera: Encyrtidae)의 발생소장을 조사하였다. 2003년과 2004년에 대학 캠퍼스에 설치된 트랩에 유살된 암컷의 수는 수컷 유살수의 317.5배와 103.4배이었고, 2004년 콩포장에서는 12.6배이었다. 콩포장에서 O. nezarae의 암컷은 8월 하순부터 유살되기 시작하여 9월 20일 전후에 가장 많이 유살되었다. 2003년과 2004년에 대학 캠퍼스에서는 8월 중하순부터 밀도가 증가하여 9월 상중순에 최성기를 나타내었다. 두 조사지역에서 모두 10월 이후에는 거의 발생하지 않았다. 톱다리개미허리노린재의 집합페로몬 세 성분, 즉 (E)-2-hexenyl (Z)-3-hexenoate(E2HZ3H)와 (E)-2-hexenyl (E)-2-hexenoate(E2HE2H) 및 myristyl isobutyrate(MI) 중에서 E2HZ3H 만이 O. nerarae에 대해 유인력을 나타내었다. E2HZ3H:E2HE2H:MI를 7:36:7로 배합한 것보다는 20:20:10이나 16.7:16.7:16.7으로 배합한 트랩에 더 많은 수가 유인되었는데, 이는 배합된 E2HZ3H의 량 때문인 것으로 추정된다.

Characterization of Acetylcholinesterase from Korean Electric Ray and Comparison with Torpedo Californica

  • Ahn, So-Soung;Sheen, Yhun-Yhong
    • Archives of Pharmacal Research
    • /
    • 제18권5호
    • /
    • pp.308-313
    • /
    • 1995
  • This study has been undertaken to examine the acetylcholinesterase (AChE) of electric organ from korean electtric ray(Narke japonica). Korean electric ray was caughted at Chungmu sea and transported to the laboratory, where electric organs were removed and stored at $-70^{\circ}C$ until used. Acelycholinesterase(AChE) of electric organ was purified by affinity column that was prepared with dicaproyl-methylpyridinium linked to Sepharose 4B. Upon purification, the specific activities in Ellman unit were increased by 52 and 39 times for high salt soluble AChE (HSSE, 870.86 $\DeltaOD/min/geam$ of tissue) and detergent soluble AChE(DSE, 105.42 .$\DeltaOD/min/geam$ of tissue), respectively. Each subunit of AChE separated by SDS polyacrylamide gel electrophoresis(SDS-PAGE)was transferred to immonilon P by western boltting and detected by mAbs raised against each subunit of AChE from electric organ og Torpedo califomica. Collagenic tails of AChE from Torpedo califomica, likewise 103Kd protein of AChE from Narke japonica was detected by monoclonal antibody specific to 103Kd of AChE from Torpedo califomica. However, molar ratio of three subunits of AChE from Narke japonica is different from that of Torpedo calicormica. Furthermore, catalytic subunit of AChE from Narke japonica was not identified by monoclnal antibody specific to catalytic subunit of AChE from Torpedo californica. These results showed differences in molecular structure of AChE from Narke japonica and AChE from Torpedo califormica eventhough they showed same enzymatic activities.

  • PDF

비균질 사질토 지반에서 단일 휨성말뚝의 수평거동에 대한 말뚝 두부 구속효과 연구 (Effect of Pile Head Constraint on Lateral Behavior of Single Flexible Pile in Non-homogeneous Sand)

  • 김병탁;김영수;정성관
    • 한국지반공학회논문집
    • /
    • 제15권5호
    • /
    • pp.65-80
    • /
    • 1999
  • 본 논문은 2개 층으로 이루어진 비균질 낙동강 사질토 지반에서 수평하중을 받은 단일 휨성말뚝의 수평거동에 대한 모형실험 결과들을 고찰하였다. 본 연구의 목적은 말뚝의 수평거동 특성에 대한 말뚝두부 구속조건(Free & Fix), 말뚝 근입길이에 대한 하부지반의 두께비(H/L), 그리고 상하부지반의 지반반력계수비$(E_{h1}/E_{h2)$의 영향에 관하여 실험적인 연구를 수행하고 이러한 영향들을 정량화 할 수 있는 실험결과를 얻었다. 모형실험 결과들에 의하면, 비균질 지반에서 수평거동은$(E_{h1}/E_{h2)$에도 의존하는 것으로 나타났다. 수평변위 측면에서의 균질지반에 대한 비균질 지반의 수평변위비$(y_{H/L}/y_{H/L}=0,\; y_{H/L}/y_{H/L}=1.0)$와 말뚝 근입길이에 대한 하부지반의 두께비(H/L)의 관계는 지수 함수식으로 표현되는 실험식을 제안하였다. 또한, 본 연구에서는 최대 휨모멘트 측면에서의 H/L 과 $MBM_{fixed-head}/MBM_{free-head}$관계는 모형실험 결과들로부터 직선함수의 실험식을 제안하였다.

  • PDF

신비탕 및 가미신비탕이 Allergy 천식 모델 흰쥐의 BALF내 면역세포 및 혈청 IgE에 미치는 영향에 관한 연구 (The Effects of Shinbi-tang and Gamishinbi-tang on Immune Cell and Serum OA-specific IgE in BALF in Rat Asthma Model)

  • 김승수;정희재;정승기;이형구
    • 대한한의학회지
    • /
    • 제23권2호
    • /
    • pp.198-210
    • /
    • 2002
  • Background : Asthma is a chronic inflammatory disorder under immunological influence. Shinbi-tang and Gamishinbi-tang are herbal decoctions used for treating asthma in traditional herbal medicine. Objective : To evaluate the effects of Shinbi-tang and Gamishinbi-tang on immune cell & serum OA-specific IgE in broncho-alveolar lavage fluid (BALF) in rat asthma model. Material and Methods : Rats were sensitized with ovalbumin (OA); at day 1 sensitized group and Shinbi-tang and Gamishinbi-tang groups were systemically immunized by subcutaneous injection of 1mg OA and 300mg of Al(OH)$_3$ in a total volume of 2ml. At the same time, 1 ml of 0.9% saline containing 6 x 10$^{9}$ B. pertussis bacilli was injected by i.p. 14 days after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerosol containing 2%(wt/vol) OA. A day after local immunization, HAL fluid was collected from the rats. Rats were orally administered with each of Shinbi-tang and Gamishinbi-tang extract for 14 days from the day after local immunization. Lymphocyte, CD4+ T cell CD8+ T cell counts, CD4+/CD8+ ratio in BALF, change of serum OA-specific IgE level, CD4+ T cell CD8+ T cell percentages in the peripheral blood were measured and evaluated. Results : Shinbi-tang and Gamishinbi-tang showed an alleviating effect on asthmatic responses of rats. Shinbi-tang decreased total cell, lymphocyte, CD4+ T cell in BALF, serum OA-specific IgE level as compared with the control group. Gamishinbi-tang decreased total cell, lymphocyte, CD4+ T cell, and CD4+/CD8+ ratio in HALF as compared with the control group. CD4+/CD8+ ratio in HALF from Shinbi-tang group and serum OA-specific IgE level from Gamishinbi-tang group didn't show any significant variation from control group. CD8+ T cell in HALF, CD3+CD4+ T cell and CD3+CD8+ T cell percentages in peripheral blood showed no significant variation among groups. Conclusion : Shinbi-tang and Gamishinbi-tang alleviated asthmatic hypen-eactivity of the rat immune system through CD4+ T cell and serum IgE. Further the study of immune system modulating mechanism is expected.

  • PDF

Theoretical Calculation and Experimental Verification of the Hf/Al Concentration Ratio in Nano-mixed $Hf_xAl_yO_z$ Films Prepared by Atomic Layer Deposition

  • Kil, Deok-Sin;Yeom, Seung-Jin;Hong, Kwon;Roh, Jae-Sung;Sohn, Hyun-Cheol;Kim, Jin-Woong;Park, Sung-Wook
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제5권2호
    • /
    • pp.120-126
    • /
    • 2005
  • We have proposed a characteristic method to estimate real composition when multi component oxide films are deposited by ALD. Final atomic concentration ratio was theoretically calculated from the film densities and growth rates for $HfO_2$ and $Al_2O_3$ using ALD processed HfxAhOz mms.W e have transformed initial source feeding ratio during deposition to fins] atomic ratio in $Hf_xAl_yO_z$ films through thickness factors ($R_{HFO_2}$ ami $R_{Al_2O_3}$) ami concentration factor(C) defined in our experiments. Initial source feeding ratio could be transformed into the thickness ratio by each thickness factor. Final atomic ratio was calculated from thickness ratio by concentration factor. It has been successfully confirmed that the predicted atomic ratio was in good agreement with the actual measured value by ICP-MS analysis.

균질 지반과 비균질 지반에서 강관 모형말뚝의 수평거동 특성에 관한 모형실험 (Model Tests on the Characteristics of Lateral Behavior of Steel Pipe Pile in Homogeneous and Nonhomogeneous Soil Conditions)

  • 김병탁;김영수
    • 한국지반공학회지:지반
    • /
    • 제14권6호
    • /
    • pp.153-166
    • /
    • 1998
  • 본 논문은 균질 및 비균질 낙동강 사질토 지반에서 수평 및 경사하중을 받은 강관 말뚝의 수평거동에 대한 모형실험 결과들을 고찰하였다. 비균질 지반은 상부와 하부층의 2개층으로 이루졌다. 본 연구의 목적은 말뚝의 수평거동에 대한 경사하중$(Q_\beta)$, 말뚝 근입길이에 대한 하부지반의 높이비 (H/S), 그리고 상.하부지반의 지반반력계수비$(E_{h1}E_{h2})$의 영향에 관하여 실험적인 연구를 수행하고 이러한 영향들을 정량화 할 수 있는 실험결과를 얻었다. 모형실험 결과들에 의하면, 비균질 지반에서 수평거동은 다른 인자들보다 $E_{h1}E_{h2}$에 더 의존하는 것으로 나타났다. 균질지반에 대한 비균질 지반의 수평변위비$(y_{H/L}/y_{H/L=0}$)와 말뚝 근입길이에 대한 하부지반의 높이비(H/L)의 관계는 지수 함수식으로 회귀분석 되었다. 경사하중을 받는 경우의 휨 모멘트-깊이 관계는 수평하중을 받는 말뚝의 경우와 상이하게 나타났으며, 상대밀도 90%에서는 최대 휨모멘트 발생깊이는 수평하중을 받는 경우보다 약 70% 깊어졌다.

  • PDF

인천 지역 준설토의 비선형 압밀특성 연구 (Characterization of Non-linear Consolidation of Dredged Soil from Incheon Area)

  • 옥영석;안용훈;이철호;최항석
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2008년도 추계 학술발표회
    • /
    • pp.1693-1706
    • /
    • 2008
  • It is of importance to determine the zero effective stress void ratio($e_{00}$), which is the void ratio at effective stress equal to zero, and the relationships of void ratio-effective stress and of void ratio-hydraulic conductivity for characterizing non-liner finite strain consolidation behavior for ultra-soft dredged materials. The zero effective stress void ratio means a transitional status from sedimentation to self-weight consolidation of very soft soil deposits, and acts as a starting point for self-weight consolidation in the non-linear finite strain numerical analysis such as PSDDF. In this paper, a new method for determining the zero effective stress void ratio has been introduced with the aid of measuring electrical resistivity of the specimen. A correlation between the zero effective stress void ratio and the initial slurry void ratio has been proposed, which can be used in PSDDF analysis as an input parameter. Combining all of the accessible experimental data, the consolidation characteristics of a dredged soil from the Incheon area has been studied in detail.

  • PDF

인체 무게 중심 분할에 따른 500m 숏트트랙 스피드 스케이팅 출발 기술 분석 (Analysis of the 500M Short track speed skating starting motion according to the center of gravity position ratio)

  • 백진호;정남주;한기훈;이용구;윤동섭;이용식
    • 한국운동역학회지
    • /
    • 제13권3호
    • /
    • pp.199-215
    • /
    • 2003
  • The purpose of this study was to attempt new starting motion and supply present starting motion in the 500M short track speed skating according to the center of gravity position. The center of gravity position ratio was divided starting motion into five(type A : front 80%-back 20%, type B front 70%-back 30%, type C : front 50%-back 50%, type D : front 30%-back 70%, type E : front 20%-back 80%). The three dimension motion analysis with DLT(direct linear transformation) method was executed using two video cameras. The following conclusion was that It was appear that reaction and execution time in starting motion was the most short in type B. It was characteristic that step of skaters was shorten and center of gravity position ratio was not effect to change of the step in each event. It was appear that the displacement of type D and type E were longer than that type A and type B during the starting motion. It was appear that skill types of center of gravity position ratio to the front were lower than that to the back and contract a posture. Observing the above, it was conclusion that skill type B of center of gravity position ratio to the tent was more effect than that to the back. But it is important that these skill type was most used to the competition and estimate the result.