• 제목/요약/키워드: L-shape

검색결과 1,855건 처리시간 0.029초

A Practice of Developing New Environment-friendly System by Composites

  • Kim, Yun-Hae;Yang, Dong-Hun;Jo, Young-Dae;An, Seung-Jun;Park, Se-Ho;Yoon, Sung-Won
    • 공학교육연구
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    • 제13권5호
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    • pp.8-14
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    • 2010
  • This study intends to study about the blade performance loss occurred due to the variation in the shape of an airfoil from attachment/non-attachment of an erosion shield for the hovercraft. The model in this study has used NACA44XXseries, has designed NACA44XX-series by using the Auto CAD, and it designed the shape that has attached an erosion shield to this model according to the thickness and length. By using these models, a grid was generated by GAMBIT and the lift coefficient ($C_l$) and the drag coefficient ($C_d$) were calculated FLUENT code for flow analysis. Through this, the $C_l$ and $C_d$ have calculated and compared the lift-to-drag ratio that an indicator of airfoil performance according to the shape and attachment/non-attachment of erosion shield.

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Development of a Polyvoltine Breed - $BL_{67}$ (Pg) of the Silkworm, Bombyx mori L. with Parthenogenetic Origin

  • Singh, Ravindra;Rao, D.Raghavendra;Gangopadhyay, Debnirmalya;Choudhary, Nazia;Kariappa, B.K.;Dandin, S.B.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제9권1호
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    • pp.41-46
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    • 2004
  • A breeding programme was initiated by utilizing a robust bivoltine breed CSR$_{18}$ and a polyvoltine breed Cambodge with the main objective of developing robust polyvoltine silkworm breeds/hybrids. At F$_1$ and F$_2$, parthenogenetic development was induced following warm water treatment of eggs at 46$^{\circ}C$ for 18 min followed by two backcrosses with Bl$_{67}$, an evolved polyvoltine breed. The newly developed breed was subjected for hybrid study using eight hybrid combinations in the laboratory at F$_{8}$ generation. F$_1$ hybrids between newly developed breed Bl$_{67}$ (Pg) and promising bivoltine breeds exhibited their superiority by expressing significant hybrid vigour for several economic characters like cocoon yield/10,000 larvae, cocoon weight, cocoon shell weight, cocoon shell ratio and denier. Study on cocoon shape variability revealed that cocoons of all the F$_1$ hybrids except BL$_{67}$ (Pg)${\times}$NB$_4$D$_2$ were found comparatively uniform in shape.pe.

대용량 인휠 모터용 중공축 냉각유로의 형상 최적화에 관한 연구 (A Study on Shape Optimization of Cooling Channel in Hollow Shaft for In-wheel Motor)

  • 임동현;김동현;김성철
    • 한국자동차공학회논문집
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    • 제21권6호
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    • pp.72-80
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    • 2013
  • For the proper cooling of in-wheel motor, the cooling channel should have the characteristics which are low pressure drop and adequate cooling oil supply to motor part. In this study, the flow performance of cooling channel for in-wheel motor was evaluated and the shape of the channel was optimized. First, the pressure drop and flow distribution characteristics of the initial channel model were evaluated using numerical analysis. Also, by the result of analysis and design modification, 4 design parameters of the channel were selected. Second, using the Taguchi optimal method, the cooling channel was optimized. In the method, nine models with different levels of the design parameters were generated and the flow characteristics of each models was estimated. Base on the result, the main effect of the design parameters was founded and optimized model was obtained. For the optimized model, the pressure drop and oil flow rate were about 0.196 bar and 0.207 L/min, respectively. The pressure drop decreased by about 0.3 bar and the oil flow rate to the motor part increased by about 0.2 L/min compared to the initial model.

휨 구조시스템의 구조디자인적 구성요소와 디자인 조합 수법 분석 (A Study on Design Methods and the Composition Elements in Flexure Structure Systems)

  • 이주나
    • 한국공간구조학회논문집
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    • 제16권1호
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    • pp.73-84
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    • 2016
  • This study analyzes the four composition elements : profile, anchorage and connection, material and member rigidity, stability, as the main composition design elements of flexure structure systems, in order to explore possibilities for more various structure designs in architectures with flexure structure system. It also examines typical design methods that use the mentioned four composition elements. At the results, this research presents an understanding of the differences between funicular shape and non-funicular shape and mechanical features of the shapes in the profile element, regarding to the ratio of rise height to span length(f/l). Also, the typical design methods are presented for the designable usages of the hinge joints and the fix joints, and for the applications of member rigidity expressed by the index of the ratio of member depth to span length(d/l). And it was presented that connection styles, addition of brace members, placement of shear walls are the main design methods in the stability element. This data would be useful to architectural designs concerning integrated design with structures.

Comparison of Two Nondestructive Methods of Leaf Area Estimation

  • Woo, Hyo-Jin;Park, Yong-Mok
    • Journal of Ecology and Environment
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    • 제32권1호
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    • pp.61-65
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    • 2009
  • We compared two nondestructive methods for leaf area estimation using leaves of 16 common plant species classified into six types depending on leaf shape. Relatively good linear relationships between actual leaf area (LA) and leaf length (L), width (W), or the product of length and width (LW) were found for ordinary leaves with lanceolate, oblanceolate, linear and sagitttate shapes with entire margins, serrate margins, mixed margins with a entire form and shallow lobes, and ordinary incised margins. LA was better correlated with LW than L or W, with $R^2$ > 0.91. However, for deeply incised lobes, LA estimation using LW showed low correlation coefficient values, indicating low accuracy. On the other hand, a method using photographic paper showed a good correlation between estimates of area based on the mass of a cut-out leaf image on a photographic sheet (PW) and actual leaf area for all types of leaf shape. Thus, the PW method for LA estimation can be applied to all shapes of leaf with high accuracy. The PW method takes a little more time and has a higher cost than leaf estimation methods using LW based on leaf dimensions. These results indicate that researchers should choose their nondestructive LA estimation method according to their research goals.

한국산 사초속 감둥사초절의 분류학적 연구 (A taxonomic study on section Atratae of Carex L. in Korea (Cyperaceae))

  • 오용자;이창숙;유경진
    • 식물분류학회지
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    • 제31권3호
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    • pp.223-251
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    • 2001
  • 한국산 사초속(Carex L.) 감둥사초절(section Atratae Kunth) 7분류군을 대상으로 외부형태학적 형질을 재검토하고, 광학현미경과 주사전자현미경을 이용하여 과낭, 수과와 잎의 표피형을 비교 분석하였다. 그 결과 얻어진 정량적 형질(줄기, 잎, 이삭, 비늘조각, 포, 과낭과 과낭부리, 수과의 길이와 너비)과 정성적 형질(이삭, 비늘조각, 과낭과 수과의 모양, 줄기와 잎의 횡단면, 비늘조각 윗 부분의 모양) 및 과낭과 수과의 표피세포모양, 잎의 표피구성요소(기본표피 세포의 모양, 세포벽 굴곡의 형태, 규소체의 수와 모양, 기공복합체의 크기와 빈도), 잎의 유두돌기와 가시돌기의 유무가 종을 식별하는데 유용하였다. 감둥사초절 7분류군은 줄기 정단부에 위치하는 이삭의 형태와 과낭부리의 모양, 수꽃이삭의 모양, 줄기의 길이에 따라 2그룹(group)으로 구분되었다. 제 1그룹은 감둥사초(C. atrata L.), 늪사초(C. buxbaumii Wahlenb.: 국명신칭), 덕진사초(C. gmelinii Hook. & Arn.), 해산사초 (C. hancokiana Maxim.)와 백두사초 (C. peiktusani Komarov)이며, 제 2그룹은 북사초(C. augustinowitzii Menish.)와 진들검정사초(C. meyeriana Kunth)이다. 또한 외부형태가 유사한 덕진사초, 해산사초와 백두사초는 비늘조각의 끝부분, 잎표피형, 수과와 과낭의 모양과 표피형에 차이가 있어 각 각을 구분할 수 있었다.

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배추흰나비 (Pieris rapae L.) 뇌간부(腦間部)의 신경세포(神經細胞)에 대한 미세구조(微細構造) (Ultrastructure of Nerve Cells in the Pars Intercerebralis of Cabbage Butterfly Pieris rapae L.)

  • 이봉희;김우갑
    • Applied Microscopy
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    • 제12권2호
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    • pp.55-68
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    • 1982
  • The study on the nerve cells in the pars intercerebralis(IP) of 5-day-old cabbage butterfly Pieris rapae L. was performed to observe their ultrastructures and classify them on the basis. of the differences in size, shape and relative distribution cf cell organelles. The brain-subesophageal ganglion complex was fixed in 1% paraformaldehyde-1% gluaraldehyde mixture and embedded in araldite mixture. The transverse thin sections of IP were stained with uranyl acetate and lead citrate and examined by Hitachi 500 and ]EM 100B electron microscope. Five distinct types. of nerve cells are recognized and are arbitrarily designated as Type I, Type II Type III, Type IV and Type V. Type I neurone: These neurones are neurosecretory cells. Several neurosecretory cells are. recognized in the pars intercerebralis. They are roughly round or peach-shaped cells measuring $13{\sim}25{\mu}m$ in diameter. The rounded nucleus shows about $5{\sim}10{\mu}m$ in diameter. The chromatin is predominantly diffused with only occasional dense patches. The perikaryon contains numerous. mitochondria, free polyribosomes and neurosecretory granules. The neurosecretory granules are relatively uniform in electron density, and each one is about $100{\sim}400{\mu}m$ in diameter and surrounded by a single membrane. The granules are also observed mostly as in groups. In one group of neurones the cisternae of endoplasmic reticulum are distended or in other group of neurones are not distended. Golgi saccules are slightly dilated at their lateral extremities and contains. frequenty dense rounded materials. Type II neurone: Thes have the largest soma in the pars intercerebralis about $30{\sim}35{\mu}m$ in diameter. They also show roughly polygonal in shape. The nucleus is elongated or sickle-shaped. The chromatin is mainly in the euchromatin form. The perikarya in these cells are well populated with populated with free ribosomes and contain numerous mitochondria and Golgi bodies. The cisternae of granular endoplasmic reticulum are also well distributed. Type III neurone: They are oval or spindle-shaped and also medium-sized. neurones approximately $15{\sim}17{\mu}m$ in length. The nucleus is oval or slightly elongated in shape and $8{\sim}9{\mu}m$ in length. The chromatin occurs in diffused form. The cytoplasm contains many filamentous or oval mitochondria. The perikaryon has also numerous free polyribosomes and cisternae of granular endoplasmic reticulum. Type VI neurone: They are roughly polygonal in shape probably due to the close approximation of the adjacent cells. The soma is about $7{\sim}8{\mu}m$ in diameter. The nucleus is round or oval in shape and $5.0{\sim}5.8{\mu}m$ in diameter. The necleus also occupies a large proprion of the cell body. The perikaryon is well populated with free ribosomes and contains several mitochondria and cistenae of granular endoplasmic reticulum. Type V neurone: These neurones are similar to Type VI neurones in various respects such as cell size and cell inclusion, but they differ from Type IV neurones in shape. The soma is oval or slightly elongated. The cell body contains several filamentous and oval mitochondria.

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고혈압 환자에서 혈압 조절 여부에 따른 신상(脤象) 및 삶의 질 비교 (A Comparison of Controlled and Uncontrolled Hypertension Groups Regarding Pulse Shape and Quality of Life)

  • 최인영;한창호;최동준;정승현;신길조;이원철
    • 대한한방내과학회지
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    • 제30권4호
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    • pp.880-892
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    • 2009
  • Objectives : This study is about a comparison of controlled and uncontrolled hypertension groups regarding pulse shape and quality of life. We aimed to find out if pulse shape would be able to help with hypertension treatment and care. Methods : We surveyed "controlled and uncontrolled hypertension patients" using SF-36, HTN QoL (measurement scale for the quality of life in hypertensive patients) and 3-D MAC pulse analyzer for pulse shape. Results : The uncontrolled hypertension group tended to have a sink pulse in the left cun. right guan & chi parts compared to the controlled hypertension group. Within the controlled hypertension group, patients who had a float pulse shape in both guan parts had a higher quality of life than patients who had a normal pulse shape. And the patients who had a normal pulse shape in both chi parts had a higher quality of life than patients with a slow or fast pulse shape. Within the uncontrolled hypertension grouP. the patients who had a normal pulse shape in right guan part had a higher quality of life than those with a choppy pulse shape. Nevertheless, these results were limited to only a few quality of life issues and were inconsistent in relation to specific pulse shapes. Conclusion : If we have more samples and better methods for collecting data, we will have better results, allowing us to improve our ability to predict and treat hypertension.

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신발류 치수체계 설정을 위안 노년 여성의 발 형태 유형화 (Classification of Foot Types for Shoes Size System of Elderly Women)

  • 박재경
    • 복식
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    • 제55권2호
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    • pp.33-44
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    • 2005
  • The purpose of this study Is to classify foot types of elderly women and young women and to suggest shoes size system by foot types for elderly women. The subjects were 321 elderly women and 181 young women. Their right feet were measured directly and indirectly by using scanner and digital camera. The anthropometric measurements were composed of 62 items. They were measured during the months of July and October in 2001 and November in 2002 The results and discussions of this study are as follows. First, in analyzing shape of the foot of elderly and young women, the shapes of foot were classified as N-type (high and narrow foot shape and wide toes), W-type (wider width for its length and severe alteration), L-type (low foot shape as oval). Second, the most characteristic foot type in elderly women was W-type. In this type, the width was wider for its length, the first metatarsophalangeal protrusion was severe and the toes were gathered at the center. On the other hand, young women belonged to N-type. Third, we suggested new size system of shoes for elderly women and the standard foot shape each type. The size system was based on foot length and foot types. Hopefully, understanding the shapes of foot and characteristics of each foot type will help to develop suitable shoes for elderly women.

Manifestation of Hybrid Vigour and Cocoon Shape Variability in Fl Hybrids of the Mulberry Silkworm, Bombyx mori L.

  • Singh, Ravindra;Rao, D.Raghavendra;Premalatha, V.;Mondal, Sipra;Kariappa, B.K.;Jayaswal, K.P.;Datta, R.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제2권2호
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    • pp.133-139
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    • 2001
  • Data from an experiment involving six polyvoltine and three bivoltine silkworm breeds have been analysed to know the level of hybrid rigour and cocoon shape variation in Fl hybrids among silkworm breeds with lows medium and high cocoon weight. Results indicated significantly positive heterosis for several quantitative characters with maximum total heterosis over mid parent value in hybrids between low and medium followed by low and low, medium and medium, low and high and high and low cocoon-weighed breeds, respectively. Study on cocoon shape measurement revelled that among Fl hybrids, cocoons of the three combinations such as GNP ${\times}$ CSR2, GNP ${\times}$ J2 and PM ${\times}$ NB4 D2 were comparatively uniform in their cocoon shape. Importance of this study to know the level of heterosis and cocoon shape variability in different silkworm crosses hale been discussed.

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