• Title/Summary/Keyword: Wings

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Controlled Flight of Tailless Insect-Like Flapping-Wing Flying-Robot (꼬리날개 없는 곤충모방 날갯짓 비행로봇의 제어비행)

  • Phan, Hoang Vu;Kang, Taesam;Park, HoonCheol
    • The Journal of Korea Robotics Society
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    • v.11 no.4
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    • pp.256-261
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    • 2016
  • An insect-like flapping-wing flying-robot should be able to produce flight forces and control moments at the same time only by flapping wings, because there is no control surface at tail just like an insect. In this paper, design principles for the flapping mechanism and control moment generator are briefly explained, characteristics measured force and moment generations of the robot are presented, and finally controlled flight of the flying robot is demonstrated. The present insect-like robot comprises a lightweight flapping mechanism that can produce a flapping angle larger than $180^{\circ}$ and a control moment generator that produces pitch, roll, and yaw moments by adjusting location of the trailing edges at the wing roots. The measured force and moment data show that the control input angles less than $9^{\circ}$ would not significantly reduce the vertical force generation. It is also observed that the pitch, roll, and yaw control moments are produced only by the corresponding control input. The simple PID control theory is used for the controlled flight of the flying robot, controlling pitch, roll, and yaw motions. The flying robot successfully demonstrated controlled flight for about 40 seconds.

Development of Compression Garments for Breast Augmentation Patients (유방 확대수술 환자용 압박의류 개발)

  • Yi, Kyong-Hwa;Choi, Hyun-Ok
    • Journal of the Korean Society of Clothing and Textiles
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    • v.44 no.1
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    • pp.1-12
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    • 2020
  • It is essential to apply compression bands or pressure garments that can stabilize the breast implants and breast shape as well as help shape the breast to the desired shape immediately after breast augmentation surgery. It is necessary to study the compression garment which is able to properly cover a deformed breast due to the operation and shape it as a beautiful breast. The subjects of the study were 6 women who experienced breast augmentation surgery with an under bust size of 70 or 75, cup size of C cup with a hemispherical and conical shape. We analyzed the dissatisfaction and satisfaction factors through the evaluation of the 4 types of commercial compression garments and developed the new functional post-operative bra which can be worn immediately after the operation according to the breast characteristics of breast augmentation patients. We have developed new bra patterns; a front opening type garment with wings and a band type garment both sides that allow the band to be pressed from the front center. The comparative wearing evaluation indicated that the superiority of the new compression garments also provided a higher the satisfaction of the newly developed bra (front adjustable style) than a commercial band.

Static Aeroelastic Response of Wing-Structures Accounting for In-Plane Cross-Section Deformation

  • Varello, Alberto;Lamberti, Alessandro;Carrera, Erasmo
    • International Journal of Aeronautical and Space Sciences
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    • v.14 no.4
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    • pp.310-323
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    • 2013
  • In this paper, the aeroelastic static response of flexible wings with arbitrary cross-section geometry via a coupled CUF-XFLR5 approach is presented. Refined structural one-dimensional (1D) models, with a variable order of expansion for the displacement field, are developed on the basis of the Carrera Unified Formulation (CUF), taking into account cross-sectional deformability. A three-dimensional (3D) Panel Method is employed for the aerodynamic analysis, providing more accuracy with respect to the Vortex Lattice Method (VLM). A straight wing with an airfoil cross-section is modeled as a clamped beam, by means of the finite element method (FEM). Numerical results present the variation of wing aerodynamic parameters, and the equilibrium aeroelastic response is evaluated in terms of displacements and in-plane cross-section deformation. Aeroelastic coupled analyses are based on an iterative procedure, as well as a linear coupling approach for different free stream velocities. A convergent trend of displacements and aerodynamic coefficients is achieved as the structural model accuracy increases. Comparisons with 3D finite element solutions prove that an accurate description of the in-plane cross-section deformation is provided by the proposed 1D CUF model, through a significant reduction in computational cost.

A Case of Thymoma Mimicking Parathyroid Adenoma (부갑상선 선종으로 오인된 흉선종 환자 1예)

  • Park, Sangheon;Hwang, Soo Min;Park, Min Woo;Jung, Kwang-Yoon
    • Korean Journal of Head & Neck Oncology
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    • v.29 no.2
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    • pp.68-70
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    • 2013
  • Thymoma is the most common anterior mediastinal mass in adult, and arises from thymic epithelial cells which includes consists various proportions of epithelial and lymphocytic aspect. Thymic epithelial cell arises from the ventral wings of the third and fourth branchial pouches in the embryo, and these cells are considered tumorous condition of thymoma. Surgical resection is main treatment of thymoma. And adjuvant chemotherapy or radiation is considered due to postoperative pathologic diagnosis. We experienced a tumor which located from left anterior neck along superior mediastinum on chest radiograph incidentally and diagnosed parathyroid adenoma clinically. After surgical removal, final pathologic report was thymoma. Here, we present the case with a review of the related literatures.

Analysis of Pheasant Carcass and Sensory Characteristics of Pheasant meat Products (꿩의 도체분석 및 꿩고기 가공제품의 관능 특성)

  • 전홍남;최성희;오홍록
    • Food Science of Animal Resources
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    • v.18 no.4
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    • pp.307-315
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    • 1998
  • To develop processed meat products of pheasant, cut-up parts of pheasant carcass was analyzed, and eight different pheasant meat products were prepared and evaluated for sensory qualities. The average live weight of pheasant was 1,089.2g, and the ratio of carcass to live weight was 75.6%. The cut-up part ratios of breast, leg, neck, back and wings to carcass weight were 33.4%, 22.5%, 5.0%, 4% and 9.5%, respectively. The chemical compositions of breast and leg meat were shown to be moisture of 73.72% and 75.58%, protein of 25.31% and 22.69%, fat of 0.28% and 0.83%, and ash of 0.84% and 0.90%, respectively. Sensory evaluation of eight different meat products of pheasant revealed that all products of pheasant meat, except frankfurt sausage, received equal or better taste score compared with products of chicken or pork, and flavor score except pressed ham and salad. Color, binding ability and particle perception scores of pheasant meat products were equal or superior to those of respective meat products of chicken or pork. The present results suggest that pheasant meat has a potential to be utilized for various value-added products and that the meat bun is the most promising product of pheasant meat. A reinforcement of color, binding ability and particle perception of meat products of other species could also be expected by addition of pheasant meat to them.

A Study on the Drilling Performance of the Assembly Machine for the an Aircraft's Main Wings (항공기 주익 조립 장비의 드릴링 성능에 관한 연구)

  • Hong, Seong-Min;Park, Dae-Hun;Han, Sung-Gil;Song, Chul-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.17 no.1
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    • pp.8-15
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    • 2018
  • Recently, the manufacturing market for low-cost airlines has led to an increase in aircraft demand. Most processes in the production of these aircrafts are manual such as drilling, sealing, and swaging. A drilling and riveting machine is a numerical-control based equipment that automatically performs drilling, sealing, and swaging operations. The accuracy of the drilled holes and the exit burr length has a significant impact on the quality of the aircraft wing during assembly. This study was conducted to identify the conditions necessary to maintain a uniform quality by controlling the rotation speed of the spindle, which directly affects the hole diameter and the quality of the exit burr.

Unsteady Lift Measurements of the Dragonfly-type Wing (잠자리 유형 날개의 비정상 양력 측정)

  • Kim, Song-Hak;Jang, Jo-Won
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.14 no.2
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    • pp.1-8
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    • 2006
  • Unsteady lift measurements were carried out in order to investigate the effects of phase difference and reduced frequency of a dragonfly-type model with two pairs of wing. A load-cell was employed to measure the lift generated by a plunging motion of the dragonfly-type model with the incidence angles of 0$^{circ}$. Experimental conditions are as follows: phase differences between fore- and hind-wings are 0$^{circ}$, 90$^{circ}$, 180$^{circ}$, and 270$^{circ}$, and reduced frequencies are 0.075, 0.15 and 0.225, respectively. The freestream velocity was 143 m/sec and corresponding chord Reynolds number was $3.4{\times}10^3$. The variation of phase-averaged lift coefficients during one cycle of the wing motion is presented. Results show that the total value of the positive lift coefficient during one cycle of the wing motion is the largest at the phase difference of 90$^{circ}$, and that the maximum lift coefficient and lift coefficient per unit of time increases with reduced frequency.

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Economy Development in Northeastern Asia and Scheme of International S&T Exchange and Cooperation (동북아 지역 경제발전과 국제 과학기술 교류협력 방안)

  • Soh, Dea-Wha;Zhu, Shiwen
    • Journal of the Speleological Society of Korea
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    • no.74
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    • pp.73-77
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    • 2006
  • Science and technology is the power of impelling the economic and social development. Promoting the international sci-tech communication and cooperation is one of the important ways of Pulling the economic development of Northeast Asia area. Sci-tech communication and cooperation between the government and the folk are two wings of international sci-tech communication and cooperation. Both are supplemented mutually and indispensable. In order to promote the economic and social development of Northeast Asia area and further strength, some suggestions are put forward, i.e. fully exerting university the main roles in the sci-tech communication and cooperation of Northeast Asia area and fully exerting Liaoning province the important roles in the sci-tech communication and cooperation of Northeast Asia area.

Comparison of Cut Meat Yield from Two Different Breeds of Broilers in Korea

  • Lee, Hyun-Jung;Lee, Se-Hyung;Yang, Chang-Ho;Lee, Jae-Cheong;Jo, Cheo-Run
    • Korean Journal of Poultry Science
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    • v.39 no.3
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    • pp.163-166
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    • 2012
  • This study was carried out to compare the cut meat yields of Cobb and Avian and their profits at productive aspect. Two different breeds, Cobb (34,086,758 birds) and Avian (4,087,600 birds) produced from January 2009 to August 2009 were used. The whole chickens were divided into cut meats including tenderloins, breast fillets, whole wings, boneless thighs, and drumsticks. The growth performance and cut meat yield of Cobb and Avian were measured to investigate possible profit difference. Cobb was superior in the aspect of production performance to Avian with significant differences in survival rate and slaughtering age. As the weight gained, the yields of Cobb increased in breast fillets and boneless thighs as well as lean meat percentage. Significantly higher yield (%) of breast fillets was produced by Cobb at size 14 when compared with Avian. However, there was no significant difference in expected market prices for both cut meat and whole chicken meat between the two breeds in all sizes.

Ferroelectric Liquid Crystals from Bent-Core Molecules with Vinyl End Groups

  • Kwon, Soon-Sik;Kim, Tae-Sung;Lee, Chong-Kwang;Shin, Sung-Tae;Oh, Lee-Tack;Choi, E-Joon;Kim, Sea-Yun;Chien, Liang Chy
    • Bulletin of the Korean Chemical Society
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    • v.24 no.3
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    • pp.274-278
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    • 2003
  • New banana-shaped achiral compounds, 1,3-phenylene bis [4-{4-(alkenyloxy) phenyliminomethyl}benzoate]s were synthesized by varying the length of alkenyl group; their ferroelectric properties are described. The smectic mesophases, including a switchable chiral smectic C $(Sm\;C^*)$ phase, were characterized by differential scanning calorimetry, polarizing optical microscopy and triangular wave method. The presence of vinyl groups at the terminals of linear side wings in the banana-shaped achiral molecules containing Schiff's base mesogen induced a decrease in melting temperature and formation of the switchable $(Sm\;C^*)$ phase in the melt. The smectic phases having the octenyloxy group such as $(CH_2)_6CH=CH_2$ showed ferroelctric switching, and their values of spontaneous polarization on reversal of an applied electric field were 120 nC/cm² (X=H) and 225 nC/ cm² (X=F), respectively. We could obtain ferroelectric phases by controlling the number of carbon atom in alkenyloxy chain of a bent-core molecule.