• 제목/요약/키워드: feathering

검색결과 35건 처리시간 0.03초

An Overview of Feathers Formation, Moults and Down Production in Geese

  • Kozak, J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제24권6호
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    • pp.881-887
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    • 2011
  • Feathers are one of the integument appendages that form the outer covering, or plumage, on birds. The goslings hatch with a downy coat of feathers formed in embryonic development. They moult the natal plumage into juvenile feathers between 3-5 weeks of age and than moult that juvenile plumage into adult plumage between 8-11 weeks of age. Feather weight of an adult goose makes up about 6.2% of its total body weight. Heritability of the feather production ability is relatively low ($h^2$ = 0.35). Within species or genotype, the quantity and composition of the plumage are affected by genetics (age, body weight or body surface area, feathering rate, sex) and environmental factors (nutrition and production system, weather, microclimate). After slaughter some 90-220 g marketable feathers can be obtained per goose. The yield of feathers and down from each hand-harvesting amounts to between 80 to 120 g per goose, depending upon the frequency and degree of completeness of the harvesting.

십자형 복합재 유연보 장착 무베어링 로터 시스템 구조동역학 해석 (Structural Dynamic Analysis of Bearingless Rotor System with Cross-shaped Composite Flexbeam)

  • 김도형;임인규;이명규;이인
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 추계학술발표대회 논문집
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    • pp.108-111
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    • 2004
  • Structural dynamic characteristics and aeroelastic stability of a small-scale bearingless rotor system have been investigated. A flexbeam is one of the most important component of bearingless hub system. It must have sufficient torsional flexibility as well as baseline stiffness in order to produce feathering motion. In the present paper, a cross-shaped composite flexbeam has been proposed for a guarantee of torsional flexibility and flapwise and lagwise bending stiffness. One dimensional elastic beam model was used for the construction of a structural model. Equivalent isotropic sectional stiffness was used in the blade model, and the flexbeam was regarded as anisotropic; which has ten independent stiffness quantities. CAMRAD II has been used for the analysis of structural dynamic characteristics of the bearingless rotor system. Rotational natural frequencies and aeroelastic stability at hovering have been investigated. Analysis result shows that the cross-shaped flexbeam has the rotational natural frequency tuning capacity.

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바인더의 종류 및 배합비율이 잉크제트 인쇄특성에 미치는 영향 (Influence of the Type and Blending Ratio of Binders on Ink-jet Printing Properties)

  • 이희명;김창근;이용규
    • 펄프종이기술
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    • 제34권2호
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    • pp.22-31
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    • 2002
  • In this paper, PVA(polyvinylalcohol), oxidized starch and SBR latex were used as binders for ink-jet printing papers, and their effects of the type and blending ratio of binders on ink-jet printing properties were compared. In case of coating color using PVA mainly used for a binder in ink-jet printing, spreading of printed letters decreased and excellent images were manifested resulting from strong hydrophilic of PVA. However, increasing solids content of coating color was somewhat limited because of the interaction of PVA and functional groups in silica as well as high molecular weight of PVA. When oxidized starch and SBR latex were mixed with PVA at desirable ratio to solve these problems, runnability in coating process was improved and good printing properties were shown. Gloss was improved when latex was used along with PVA as a binder because of the thermoplastic property of the latex. From this result, possibilities of high solids content and high gloss ink-jet printing papers were investigated.

화상분석을 통한 전통 수록지의 서화 특성 비교 (Comparison of the Painting and Writing Properties of the Traditional Handmade Papers by Image Analysis)

  • 민춘기;조중연;이선호
    • 펄프종이기술
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    • 제32권4호
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    • pp.81-86
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    • 2000
  • Hanji is a traditional handmade paper, which has been famous for its excellent qualities in strength, whiteness, gloss, and smooth feel in painting and writing in ancient Far East for many years. Nowadays, however, its old fame has declined and it has been used only in limited extent such as in traditional Korean brush painting and writing. In this study, 9 kinds of commercial handmade papers made in Korea, China, and Japan were collected and their printing and writing properties were evaluated by image analysis. Chinese handmade paper showed the best result in absorption area of China ink, the roundness and feathering of China ink blots, followed by Hanji. Abrasion coefficient of the Chineses papers was higher than that of the others, which was regarded to contribute to the difference in touch feeling of the writing brush on the papers. It was shown that absorption rate and blot area of China ink were increased by Dochim. Hanji which has recently been made by so called \"traditional method\" showed no quality difference from the modified Hanji.ied Hanji.

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Inkjet Printing on the Grain Leather: Evaluation of Line Image Quality on the Grain Leather

  • Park, Heung-Sup;Park, Soo-Min
    • 한국염색가공학회지
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    • 제19권2호
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    • pp.24-31
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    • 2007
  • This paper addresses factors of line image quality on grain leather printed via inkjet printer. Lines were printed onto coated leather media, and line width, edge blurriness, and edge raggedness were evaluated for line image quality. Various factors influenced to wetting and capillary wicking were studied and found out that wicking through capillary between fibers causes significant feathering on leather surface similar with pulp capillary in copy Paper. Polyurethane and acrylic resin coating resulted good image qualify by reducing capillary wicking. The mixture of polyurethane and acrylic resin applied on grain leather satisfied with both image quality and surface hand. $AllWrite^{TM}$ ink brought best results of image quality, comparing with $VeraPrint^{TM}$ ink and $JetWrite^{TM}$ ink.

Elimination of SPFMV from Virus-infected Sweet Potato Plants through Apical Meristem Culture

  • Kim, Young-Seon;Jeong, Jae-Hun;Park, Jong-Suk;Eun, Jong-Seon
    • Plant Resources
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    • 제7권3호
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    • pp.200-205
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    • 2004
  • Sweet potato infected with a viral disease (SPFMV) showed irregular chlorotic patterns, so called feathering associated with faint or distinct ring spots that have purple-pigmented borders. SPFMV was eliminated from sweet potato plants using meristem tip culture. MS medium supplemented with BAP (2mg/L) and NAA (0.05 mg/L) was used for shoot proliferation and 1/2 MS medium for rooting of the plants. Highest percentage of regenerated plants (60%) was obtained from the optimum size (0.3-0.5mm) meristem tips. Of these, 60% plants were found negative for SPFMV by RT-PCR. Virus detection by RT-PCR was found to be a reliable method. Meristem-tip culture to produce SPFMV-free quality sweet potato and virus detection by RT-PCR is an efficient, time saving and reliable method for production of SPFMV-free tissue culture raised plants.

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슈퍼 커패시터를 장착한 풍력발전용 피치 시스템 개발 (The Development of Blade Pitch System Using Super Capacitor Storage)

  • Choi, Hee-young;Ryu, Ji-su;Lee, Sang-ho
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2012년도 전력전자학술대회 논문집
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    • pp.311-312
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    • 2012
  • Blade pitch control system monitors and adjusts angle of the blades and controls rotation speed of blades. This paper shows 2MW pitch system hardware and electric part. Blade pitch system consists of pitch drive, gear box, motor and energy storage. Fieldbus is base on CANopen protocol. Fail-Safe system moves the blades to a safety position in case of any fault condition. The super capacitor energy storage provides emergency back up to the Pitch servo driver during feathering the blades. This paper studied Blade pitch servo driver and a bi-directional DC-DC converter for fail-safe system.

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압전작동기 LIPCA로 구동하는 곤충 모방 날갯짓 기구 (Insect-mimicking Flapping Device Actuated by a Piezoceramic Actuator LIPCA)

  • 박훈철;모 사이푸딘;윤광준;구남서
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.719-722
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    • 2005
  • In this paper, we present out recent progress in the LIPCA (Lightweight Piezo-Composite Actuator) application for actuation of a flapping wing device. The flapping device uses linkage system that can amplify the actuation displacement of LIPCA. The feathering mechanism is also designed and implemented such that the wing can rotate during flapping. The natural flapping-frequency of the device was about 9 Hz, where the maximum flapping angle was achieved. The flapping test under 5 Hz to 15 Hz flapping frequency was performed to investigate the flapping performance by measuring the produced lift and thrust. Maximum lift and thrust were produced when the flapping device was actuated at about the natural flapping-frequency.

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Control Effectiveness Analysis of the hawkmoth Manduca sexta: a Multibody Dynamics Approach

  • Kim, Joong-Kwan;Han, Jae-Hung
    • International Journal of Aeronautical and Space Sciences
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    • 제14권2호
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    • pp.152-161
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    • 2013
  • This paper presents a control effectiveness analysis of the hawkmoth Manduca sexta. A multibody dynamic model of the insect that considers the time-varying inertia of two flapping wings is established, based on measurement data from the real hawkmoth. A six-degree-of-freedom (6-DOF) multibody flight dynamics simulation environment is used to analyze the effectiveness of the control variables defined in a wing kinematics function. The aerodynamics from complex wing flapping motions is estimated by a blade element approach, including translational and rotational force coefficients derived from relevant experimental studies. Control characteristics of flight dynamics with respect to the changes of three angular degrees of freedom (stroke positional, feathering, and deviation angle) of the wing kinematics are investigated. Results show that the symmetric (asymmetric) wing kinematics change of each wing only affects the longitudinal (lateral) flight forces and moments, which implies that the longitudinal and lateral flight controls are decoupled. However, there are coupling effects within each plane of motion. In the longitudinal plane, pitch and forward/backward motion controls are coupled; in the lateral plane, roll and side-translation motion controls are coupled.

한국의 조우관과 중국의 할관 비교 연구 -조우의 상징적 의미와 변천과정을 중심으로- (A Study of comparing Korean Jowoo-Guan(조우관) and Chinese Hal-Guan(할관) - Focusing on transition and symbolism of the plume in the cap -)

  • 신경섭
    • 복식
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    • 제50권4호
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    • pp.89-102
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    • 2000
  • The purpose of this study was to research Korean Jowoo-Guan and Chinese Hal-Guan and study transition and symbolism of the birds feather in the cap. The culture of ancient Korea was influenced by North Asia prior to the influence of the Chinese culture, One of the remarkable thing, as the cultural factor of North Asia is the birds worship thought. Korean Jowoo-Guan was derived from the birds worship thought. So in dealing with the plume of Korean Jowoo-Guan, we must recognize Worship to the bird and the symbolical meaning of the bird. The results of study was as follow. 1. Korean Jowoo-Guan was influenced worship to the sun, so it's wearing symbolized the governing class. As the Social development and governing class, the feathering cap was developed to a gold crown, and also the gold crown of Samguk times had been influenced style of North Asia culture. But afterwards the symbolical meaning of the bird was waning, only decorative meaning was remained. 2. Chinese Hal-Guan was warn in Joo-dynasty, but the symbolism of the plume in the cap was not similar to Korean Jowoo-Guan. Chinese Hal-Guan was symbolized bravery of superfluous soldier than Worship to the bird. But afterwards the symbolical meaning of bravery of superfluous soldier was waning, only decorative moaning was remained. 3. Though neighbor countries have mutually influenced and have similar cultural style, they have symbolism of themselves

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