• 제목/요약/키워드: Two branches

검색결과 539건 처리시간 0.033초

주덕트의 단면적 변화가 분지덕트의 유량분배에 미치는 영향 (Effect of a Variation of a Main Duct Area on Flow Distribution of Each Branch)

  • 이재호;김범준;조대진;윤석주
    • 설비공학논문집
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    • 제17권4호
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    • pp.386-395
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    • 2005
  • With the development of a living standard, the importance of indoor air conditioning system in all kinds of buildings and vehicles has increased. A lot of researches on energy losses in a duct and various kinds of flow pattern in branches or junctions have been carried out over many years, because the primary object of a duct system used in HVAC is to provide equal flow rate in the interior of each room by minimizing pressure drop. In this study, to get equal flow distribution in each branch, a blockage is applied to the rectangular duct system. The flow analysis for flow distribution of a rectangular duct with two branches was performed by CFD. By using SIMPLE algorithm and finite volume method, flow analysis is performed in the case of 3-D, incompressible, turbulent flow. Also, the standard $k-{\varepsilon}$ model and wall function method were used for analysis of turbulent fluid flow. The distribution diagrams of static pressure, velocity vector, turbulent energy and kinetic energy in accordance with variation of Reynolds number and blockages location in a rectangular duct show that flow distribution at duct outlets is improved by a blockage. In this rectangular duct system, mean velocity and flow rate distribution in two branch outlets are nearly constant regardless of variation of Reynolds number, and a flow pattern of the internal duct has a same tendency as well.

반사 손실 합성법을 이용한 GSM900/DCS1800/PCS1900 내장형 안테나 설계 (Internal Antenna Design for GSM900/DCS1800/PCS1900 Using an Overlap of Return Loss)

  • 장병찬;김채영
    • 한국전자파학회논문지
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    • 제18권5호
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    • pp.503-510
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    • 2007
  • 본 논문은 GSM900, DCS1800, PCS1900 대역을 동시에 만족시킬 수 있는 삼중 대역 안테나 설계에 관한 연구이다. 제안된 구조는 소형화와 견고성을 위해 유전체 위에 2개의 금속 가지를 접어서 만든 형태이다. 금속 가지의 길이를 조정하여 반사 손실을 합성시켜서 광대역을 구현하였다. 안테나의 반사 손실은 모의 실험을 통해 구하였으며, 이를 측정값과 비교하였다. 모의 실험은 상용 툴인 Ansoft사의 HFSS 9를 사용하였고, 수치 비교 결과, 원하는 주파수 대역에서 -10 [dB] 이하의 반사 손실을 얻었다. 또한, 안테나의 이득과 복사 패턴을 원거리장 측정 시스템을 사용하여 전파 무반사실에서 측정하였다. 측정 결과 최대 이득은 3.0 [dBi], 평균 이득은 -1.0 [dBi] 이상의 양호한 특성을 보였으며, 대역 내 2개의 주파수의 복사 패턴은 서로 유사하였다.

감각 유리견갑피판술 (Sensory Bearing Scapular Free Flap)

  • 정덕환
    • Archives of Reconstructive Microsurgery
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    • 제7권1호
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    • pp.20-27
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    • 1998
  • Among many kinds of introduced free flaps, scapular freeflap is one of the most popularly using modalities in fasciocutaneous defect coverage with minimal donor defect and easier procedure and constant vascular patterns of the donor. Many surgeons who had experience of this flap pointed out deficit of the reliable sensation of the transplanted flap is the main shortcoming of the scapular free flap. If we can subjugate that point, scapular free flap is the most excellent procedure in such a cases as heel pad reconstruction and hand reconstruction which are relatively important to have skin with protective sensation. Author performed anatomical literature review, 10 cadaveric dissections and 12 clinical dissections. In surgical anatomical aspect, the upper six dorsal rami of the thoracic nerves have medial branches which pierce Longissimus thoracis and Multifidus muscle with small cutaneous twigs which pierce Latissimus dorsi and Trapezius muscle. Among that cutaneous twigs, several twigs distribute to the skin of the back from midline to lateral aspect which territory is identical to scapular free flap. We analysed clinical experiences of that sensory bearing scapular free flap surgical anatomy and one year follow-up studies with several results. 1) Two to three cutaneous twigs which pierced from the Trapezius muscle over the scapular free flap region. 2) Each twigs has two to four nerve fascicles with small artery. 3) The nerve distributed to the ordinary scapular free flap and large enough size and pedicle length to neurorrhapy with various recipient site nerves. 4) The inconvenience of this procedure is the vascular pedicle and nerve pedicle have opposite directions, vascular pedicle of that comes from lateral direction from subscapular vessels, but nerve pedicle comes from medial direction from trapezius muscle. Author can found constant cutaneous nerve branches which come from piercing the Trapezius. This nerves are helpful for protective sensation in transplanted scapular free flap. We can't had enough follow-up and evaluation of the nerve function of this procedure, we need continuous research works to application of this procedure. The in conveniences come from directional differences of pedicle can solve with longer harvest neural pedicle and change direction of the neural pedicle.

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홍화의 작물학적 특성에 의한 품종군 분류 (Classification of Safflower(Carthamus tinctorius L.) Collections by Agronomic Characteristics)

  • 방경환;김영국;박희운;성낙술;조준형;박상일;김홍식
    • 한국약용작물학회지
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    • 제9권4호
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    • pp.301-309
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    • 2001
  • 홍화 수집종들의 작물학적 특성을 통하여 유전적 다양성 및 유연관계를 밝히고, 품종군을 분류하여 품종육성의 기초자료로 이용코자 시험한 결과를 요약하면 다음과 같다. 개화일수는 $74{\sim}88$일 분포로 평균 83일이었고, 80일 이하의 조숙성을 가진 수집종은 21개 이었으며, 1차분지수와 2차분지수는 각각 $3.8{\sim}14.8$개와 $0{\sim}26.9$개의 범위로 분포하였고, 다분지형의 특성을 가진 품종은 IT201434, IT202723 등 이었으며, 생육특성 중 2차 분지수의 변이가 켰다. 수량구성 요소로서 두상화수는 $5.0{\sim}40.7$개, 두상화당 종실수는 $25{\sim}68$개, 100립중 및 주당 종실중은 각각 $2.9{\sim}5.4g,\;3{\sim}47.5g$의 범위로 분포하였고, 종실중 > 두상화수 > 두상화당 종실수 순으로 변이가 큰 경향이었다. 수집종들은 작물학적 특성에 따라 11개군으로 분류되었으며, I군은 25%, II군은 33%, III군은 14%, IV군은 8%, VI군은 3%, IX군은 2%, X군은 1%, ?군은 1%가 속하였으며, III군은 모두 국내재래종 이었다. 분류된 군중 X군은 출아소요일수가 짧고, 개화소요일수가 길었으나 수량 구성 요소인 두상화수, 주당 종실중 및 두상화당 종실수가 가장 우세한 군으로 분류되었다. 수량구성요소인 두상화수와 주당 종실중은 경직경, 제1차분지수, 제2차분지수, 엽수 및 엽장과 높은 정의 상관을 보였다.

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검정콩 기계조파시 파종시기와 밀도가 생육 및 수량에 미치는 영향 (Effects of Planting Date and Density by Drill Seeder on Growth and Yield of Black Soybeans)

  • 주정일;김칠현;문창식;함수상;인민식;정길웅
    • 한국작물학회지
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    • 제41권2호
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    • pp.215-222
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    • 1996
  • 경장이 뚜렷이 다른 검정콩 2계통에 대하여 트렉터 부착 세조파기를 이용한 조파시 재배시기 및 파종밀도 차이가 생육 및 수량특성에 미치는 영향을 검토코자 하였다. 공시품종은 중경종인 검정콩 001와 단경종인 수원 157호이었고, 파종은 5월 21일과 6월 19일에 트렉터 부착 세조파기를 이용하여 조파하였다. 파종밀도는 m$^2$당 8.3본(60$\times$20cm), 11.0본(60$\times$15cm), 16. 7본(60$\times$l0cm), 22. 0본(60$\times$7.5cm), 33.0본(60$\times$5cm)등 5처리를 두었다. 1. 수량 구성요소와 수량에서 중경종인 검정콩001는 적만파간 파종밀도 반응이 비슷한 경향이었으나 단경종인 수원157호는 적만파간 파종밀도 반응이 다르게 나타났다. 2. 생육, 수량구성요소 및 수량에서 파종기와 품종, 파종기와 파종밀도와의 상호작용은 대부분의 형질에서 유의성이 인정되었으나 품종과 파종밀도와의 상호작용은 유의성이 없었다. 3. 도복과 수량에서 검정콩001는 만파적응성이 $\lrcorner$높았고, 수원157호는 적파적응성이 높았다. 4. 재배시기와 파종밀도 차이에 따른 변이가 높은 형질은 경장, 분지수, 개체당 입수, 수량 등이였고 변이가 낮은 형질은 주경절수, 협당립수, 100립중 등이었다.

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Studies on the Fruiting Phase of Rape Under the Different Cultural Conditions

  • Kae, B.M.
    • 한국작물학회지
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    • 제12권
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    • pp.77-87
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    • 1972
  • The fruiting phase of rape under transplanting and direct-sowing conditions has been studied at Mokpo during the 2 years period from 1970 to 1971. Two varieties, Yudal and Miyuki were used in this study. The planting space and sowing time were also incorporated into this study. The results could be summarized as follows: 1. The plant tape of rape was nearly umbrella-shaped of all, but has changed to the laid elliptical-shaped, broadly ovate and spindle-shaped under different varieties and cultural conditions in the plant diagram(Fig. 2). 2. The length of the primary branches for each nodes had a tendency to the symmetric apical curve with the apex at the upper 10-12th node in the transplanting. but to the upper bias apical curve with the apex at the upper 5-7th node in the dense-sowing(Fig.3). 3. The ear of main stem was longer, more pods, heavier 1, 000 grains and more grain yield than ear of primary branches of all, Especially, as for that, the rate of yield constitution per plant in the direct-sowing was higher than in the transplanting(Fig. 4, 5, 6, 7, 8, 9). 4. The ear-length of the primary branches for each nodes had a tendency to the relatively slowly apical curve with the apex at the upper 3-4th node in the transplanting, but to the lower bias apical curve with the apex at the upper 2nd node in the dense-sowing. Especially, the possibility of growth at the lower ears was few in the early variety (Fig. 4). 5. The number of pod per ear on the primary branches for each nodes had a .tendency to the curve of ear-length with the apex at the upper 5-8thnode in the transplanting and at the upper 4-5th node in the dense-sowing (Fig. 5). Accordingly, a high positive correlation was found between the ear-length and number of pod per ear (Table 2) 6. In the transplanting, the high rate of effective ear was from the upper nods to the 12th node, but below the 16-17th nodes was ineffective. However, in the early dense-sowing the high rate of effective was to the 7th node. but below the 10th nodes was. ineffective. Especially, in the early variety has difficult to secure of poi-numbers for ineffective of the lower nodes(Fig. 6.). 7. The density of pod setting of the ear of main stem was the longest of all ears, and the lower nods were, the shorter it became. That had a tendency to the evidently apical growth. However. in the early variety, it was lengthened according to growth of ear-length(Fig.7). 8. The pod-length of the medium nodes was longer than the upper and lower, and the possitive correlation between pod-length and number of grain per poi was very high(Table 2.). 9. In the grain yield per node of primary branches, the most yielding node of transplanting was the upper 9th node, of dense-sowing 4-5th node(Fig 8.), and the possitive correlation between grain yield per node and ear-length or number of pod per ear was very high(Table 2). 10. The grain yield of ear of main stem was higher than that of primary branches in the percentage of dependence for grain yield per plant. The limint node of 50% of dependence to cumulative grain yield per plant was the upper 7-8th node in tranplanting, in the early dense-sowing 4-5th node, and in tke late dense-sowing-3th node(Fig. 9). 11. In the weight of 1, 000 grains the lower nodes were, the lighter it becames in dense-sowing. Therefore, this was also lighter than in the transplanting to the (Fig. 10.). 12. The oil content of grain at the medium nodes was low in the early variety, but at the ear of main stem and upper 1st node it was extremely high(Fig. 11.).

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Developmental Morphology of Osmundea crispa (Ceramiales, Rhodophyta) from California

  • Nam Ki Wan;Choi Han Gil
    • Fisheries and Aquatic Sciences
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    • 제2권1호
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    • pp.25-31
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    • 1999
  • Developmental morphology of the red alga, Osmundea crispa (Hollenberg) Nam from California was studied on the basis of liquid-preserved and herbarium specimens. Vegetative axial segment of the species produces two pericentral cells and one trichoblast. Spermatangial filaments (branches) are derived from apical and epidermal cells in pocket-shaped apical pit with an ostiole-like upper opening. Procarp-bearing segment of female trichoblast produces five pericentral cells, of which the fifth functions as supporting cell of carpogonial branch. Tetrasporangial production occurs in random epidermal cells in apical pit of branchlets, and two presporangial cover cells show parallel arrangement to stichidial axis. As this vegetative and reproductive development is included in the generic delineation of Osmundea Stackhouse, O. crispa among the known Osmundea species is characterized by habit forming compact cushion-like clump with angular to terete thallus. It is also distinguished from O. hybrida (AP. de Candolle) Nam without the compressed thallus by the number of pericentral cells in procarp-bearing segment and shape of spermatangial pit. Taxonomic implication of the shape of spermatangial pit is also included.

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On the origin of the extended horizontal branch and the Sandage period-shift effect in the two metal-poor globular clusters NGC2419 and M15

  • Jang, Sohee;Joo, Seok-Joo;Na, Chongsam;Lee, Young-Wook
    • 천문학회보
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    • 제38권2호
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    • pp.62.2-62.2
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    • 2013
  • Recent spectroscopic observations have provided evidence for complex chemical evolution by supernovae and/or asymptotic giant branch (AGB) stars in the two metal-poor globular clusters (GCs) NGC2419 and M15. In particular, the horizontal branches (HBs) of these metal-poor GCs are very extended in the Hertzsprung-Russell diagram. The origin of these peculiar features, as well as that for the Sandage period-shift effect observed in these clusters, are yet to be understood. Here we show, by constructing population models including the Nitrogen enhanced subpopulation, that the second generation populations in these clusters would be enhanced not only in Helium, but also in Nitrogen. This working hypothesis can simultaneously explain the observed extended feature on the HB and the period-shift of RR Lyrae variables.

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Semi-trusted Collaborative Framework for Multi-party Computation

  • Wong, Kok-Seng;Kim, Myung-Ho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제4권3호
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    • pp.411-427
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    • 2010
  • Data sharing is an essential process for collaborative works particularly in the banking, finance and healthcare industries. These industries require many collaborative works with their internal and external parties such as branches, clients, and service providers. When data are shared among collaborators, security and privacy concerns becoming crucial issues and cannot be avoided. Privacy is an important issue that is frequently discussed during the development of collaborative systems. It is closely related with the security issues because each of them can affect the other. The tradeoff between privacy and security is an interesting topic that we are going to address in this paper. In view of the practical problems in the existing approaches, we propose a collaborative framework which can be used to facilitate concurrent operations, single point failure problem, and overcome constraints for two-party computation. Two secure computation protocols will be discussed to demonstrate our collaborative framework.

후 경골 정맥의 정맥류에 의해 발생된 족근관 증후군(2예보고) (Tarsal Tunnel Syndrome secondary to the Varicosis of Posterior Tibial Vein (Two Cases Report))

  • 이진영;김갑래;반태서
    • 대한족부족관절학회지
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    • 제12권2호
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    • pp.216-219
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    • 2008
  • Tarsal tunnel syndrome is a complex of symptoms resulting from the compression of the posterior tibial nerve or its branches. Many studies have done on etiologic agents. We reported two cases of tarsal tunnel syndrome secondary to the varicosis of posterior tibial vein. Symptoms were relieved after excision of the varicosis, neurolysis and reposition of posterior tibial nerve.

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