• Title/Summary/Keyword: Concept Weight

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Tilt Rotor-Wing Concept for Multi-Purpose VTOL UAV

  • Hwang, Soo-Jung;Kim, Yu-Shin;Lee, Myeong-Kyu
    • International Journal of Aeronautical and Space Sciences
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    • v.8 no.1
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    • pp.87-94
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    • 2007
  • Tilt rotor-wing concept to show enhanced performance in low speed mission is presented. Three types of stud wings on the existing tilt rotor configuration are suggested and their characteristics are compared. Aerodynamic analysis indicates that the stud wing concept gives significant performance improvement on the endurance and range in the low speed regime when compared with the tilt rotor. Penalties of the stud wing are discussed from the perspectives of conversion corridor, structural weight, configuration design, and cross wind stability. This study concludes that the advantage of the stud wing in general UAV mission performance is so significant as to surpass the penalties in other perspectives investigated.

Shape Optimal Design to Minimize the Weight of a Mask-Frame for OLED Vapor Deposition (OLED 증착용 마스크 프레임의 무게 최소화를 위한 형상최적설계)

  • Lee, Boo-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.4685-4693
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    • 2013
  • Present work deals with a shape optimal design to minimize the weight of the mask-frame used in the process of OLED vapor deposition by the fine metal mask. A design concept for an optimal shape of the frame to increase the stiffness and to reduce the weight is derived using the topology optimization, shape design variables of the frame by adopting slots being defined. An optimal shape is determined by solving the shape optimization problem to minimize the weight of the frame under constraints of the maximum displacement. Weight of the optimal design is 117.6 kg, which is reduced by 138.4 kg(54.1%) of that of the first design, 256 kg.

A Study on the Light-weight Roof Structure of Urban Hanok - Focused on the Cases in Jung-gu, Daegu - (경량식 상부구조를 가지는 도시한옥에 관한 연구 - 대구 중구를 중심으로 -)

  • Park, Jun-Hyun;Cho, Jae-Mo
    • Journal of architectural history
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    • v.22 no.6
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    • pp.23-34
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    • 2013
  • The purpose of this study is to look into the weight-lightening phenomenon of the roof structure of some Hanok(韓屋), the Korean traditional houses found from the survey on the distribution and actual state of urban traditional houses existing in the whole region of Jung-gu, Daegu, Korea. As a result of judging from the pre-test of building registers for the research area, approximately 5,000 wood structure houses were found. A field data survey based on these findings showed that there are 1,752 Hanok houses. And the further classification of the Korean traditional houses by roof structure type shows that about 35% of them underwent weight lightening. While this kind of light-weight Hanok is different from the concept of traditional Hanok, they also show the survival method of Hanok that reflects the economical and technological phases of that period. It is expected that deeper understanding on the urban traditional houses will be possible through carrying out in-depth researches on techniques of the light-weight roof structure of the urban traditional houses that are supposed to have functioned as dwellings as commercial products.

Detection and Management of Misbehaving Node in Tactical Ad-Hoc Networks (전술 Ad-hoc 네트워크에서의 비정상행위 노드 탐지 및 관리)

  • Jang, Beom-Geun;Lee, Soo-Jin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.3
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    • pp.333-343
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    • 2009
  • Tactical Information Communication Network(TICN) is a concept-type integrated Military Communication system that enables precise command control and decision making by unifying the diversified military communication network and conveying diverse range of battle field information on real-time, at right place at right time. TICN is designed to advance into high speed, large capacity, long distance wireless relay transmission. To support mobility in battlefield environments, the application of Ad-hoc networking technology to its wireless communication has been examined. Ad-hoc network is consist of mobile nodes and nodes in the network depends on the cooperation of other nodes for forwarding of packets. In this context, some non-cooperating nodes may delay forwarding of packets or drop the packets. This may hamper the network as a whole and disrupt communication between the cooperating nodes. To solve this problem, we present a solution with a Node Weight Management Server(NWMS), which manages each node's weight according to its behavior in local area. When the NWMS detects misbehaving node, it increases the node's weight. If the node's weight exceeds a predefined threshold then the NWMS broadcasts the node's information into network to isolate the misbehaving node from the network. These mechanisms show that they are highly effective and can reliably detect a multitude of misbehaving node.

A Study of Self-Concept and Body Image in High Risk Adolescents for Eating Disorders (식사장애 고위험 청소년의 자기개념과 신체상에 대한 연구)

  • Kang, Jae-Seong;Lee, Young-Ho;Han, Sung-Hee;Rhee, Min-Kyu
    • Korean Journal of Psychosomatic Medicine
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    • v.4 no.1
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    • pp.3-12
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    • 1996
  • Objects : This study was attempted to evaluate the body image and the self concept in high risk adolescents for eating disorders. Methods 589 middle school students were investigated with EAT(Eating Attitude Test) and BITE(Bulimic Investigatory Test Edinburgh) and Schematic Figures(Child/Adolescent Version) and Piers-Harris Self-Concept Scale. According to the score of EAT and BITE, three high risk groups(high EAT group, high BITE group, high EAT & BITE group) were identified. Three groups were examined in terms of sex, weight, self concept and body image. Each group was EAT group, BITE group, EAT & BITE group Results: The results of the study were as follows : 1) EAT & BITE group showed greatest body image distortion. 2) BITE group and EAT & BITE group showed lower score in self concept scale. 3) The majority of EAT group were boys, BITE group and EAT & BITE group were mostly girls. 4) All three high risk groups, especially Bin group, revealed overweight compared with normal control group. Conclusions : High BITE group and high EAT & BITE group could be considered as significantly high risk groups for eating disorders, showing overweight, severe body image distortion, and poor self concept. EAT score alone seemed not to discriminate high risk adolescents for eating disorders.

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Development of Variable Rate Granule Applicator for Environment-Friendly Precision Agriculture (I) - Concept Design of Variable Rate Pneumatic Granule Applicator and Manufacture of Prototype - (친환경 정밀농업을 위한 입제 변량살포기 개발 (I) - 송풍식 입제 변량살포기 개념설계와 시작기 제작 -)

  • Ryu K.H.;Kim Y.J.;Cho S.I.;Rhee J.Y.
    • Journal of Biosystems Engineering
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    • v.31 no.4 s.117
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    • pp.305-314
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    • 2006
  • Precision farming has been known as an environment friendly farming technology. This study was conducted to develop a variable-rate granule fertilizer applicator as an attempt for introducing the precision farming technologies to rice cultivation in Korea. In this paper, concept design process and manufacturing of prototype variable rate granule applicator was reported. For concept design, some design guide lines were selected. Based on the design guide line and some engineering knowledge, concept design was conducted. The designed prototype granule applicator was mounted at the rear of riding type cultivator for paddy field and had a 10m wide boom structure with pneumatic conveying and application system as well as 1GPS receiver, 1 granule hopper, 12 blow heads, 2 metering devices and 1 controller. The fertilizer applicator had 942 ka of weight, 740m of ground clearance and 1,117mm of center of gravity from the ground. The applicator was designed to be able to $34{\sim}428kg/ha$ of granule at $0.2{\sim}0.8m/s$ of fertilizer working speed.

Concept Analysis of Effective Breastfeeding (효과적인 모유수유 개념 분석)

  • Yang, Huyn-Joo;Seo, Ji-Min
    • Women's Health Nursing
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    • v.17 no.4
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    • pp.317-327
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    • 2011
  • Purpose: This study was conducted to analyze and clarify the concept of the effective breastfeeding. Methods: This study used Walker and Avant's process of concept analysis. Results: Effective breastfeeding is how to give infant adequate milk, which fulfills needs of mother and infant, from her breast so that they can be satisfied with the process and results. It included the effective breastfeeding properties as follows: feeding behaviors (positioning, latch on, and suckling), transferring a breast milk to an infant, mother-infant interaction, and satisfying their desires (satisfaction, comfort, mother's self-confidence, infant's adequate weight gain and defecation, adequate breastfeeding interval). The antecedent of effective breastfeeding were anatomical and functional normal breast, breastfeeding knowledge and steady-state of mother, and feeding desire, rooting reflex and normal oral cavity of infant. The consequences of effective breastfeeding were exclusive breastfeeding, infant and maternal health and wellbeing, and achievement of mother and infant attachment. Conclusion: The meaning of effective breastfeeding defined in this study will contribute to develop the effectiveness breastfeeding assessment tool and the nursing intervention for ineffective breastfeeding.

A Study of Wheel Guards for Reduction of High Frequency Road Noise (고주파수 소음 저감 휠가드 연구)

  • Kim, Hyungyung;Baik, Hongsun;Lee, Moonsuk;Kim, Donghyo;Kim, Dohyung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.3
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    • pp.12-18
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    • 2014
  • This paper describes about the development of new concept's rear wheel guards for the reduction of Road Noise in the passenger vehicle using test. The new wheel guards are proposed by various frequency chamber concept and different textile layers concept. Two wheel guards were verified by small cabin resonance test and vehicle test. Through new developing process without vehicle test, Result of road noise will be expected when new concepts and materials of wheel guard is applied into automotive vehicle. As a result of the application of Aimed Helmholtz and Multi-layers concept, this paper classifies the road noise, cost and weight are reduced by new concepts and the solutions are adopted into the 2 cars.

The Effects of Teaching Methods on Conceptual Change of Atmospheric Pressure in Middle School Students (수업방안이 중학생들의 대기압 개념 변화에 미치는 영향)

  • Kim, Jong-Hee;Bae, Ju-Hyeon;Lee, Yong-Seob;Kim, Sang-Dal
    • Journal of the Korean earth science society
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    • v.25 no.4
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    • pp.214-221
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    • 2004
  • The purpose of this study is to inquire into the effects of teaching methods in the class on the conceptual change of atmospheric pressure for middle school students. After analyzing the concept of atmospheric pressure in the middle school science textbooks on the present 7th Curriculum, classes were performed adopting classified Method A and Method 3. For Method A, the textbook is used to explain the concept in the view of weight. For Method B, the textbook is used to approach the concept in the views of molecular movement as well as of weight. This study consists of four classes in the third grade students of middle school in Busan, where they were divided into the Method A group and the Method B group. These study was carried out with pre-post on each of these classes on the learning achievement and on the conceptual change of atmospheric pressure. The results of this study were as follows: First, the effect on the learning achievement was displayed the average score of the Method B was showing a meaningful difference comparing to the Method A. Second, the effect on the conceptual change measured by verifying the score for the difference among the averages for each sub-scale three out of four conceptual factors,'the direction of atmospheric influence and the reason','the principle of atmospheric action' and 'the atmospheric changes by the temperature rise on the surface of the earth and the reason', showed meaningful improvement. But, the one left factor,'the distribution of atmospheric pressure by altitudes and the reason', displayed no meaningful difference. Third, The concept of atmospheric pressure is better defined as the pressure created by the movement of air particles, in the view of kinetic theory of gas, rather than explained by the notion of the weight of air.

The Effects of Teaching Methods in the Class on Conceptual Change of Atmospheric Pressure in Middle School Students (수업방안이 중학생들의 대기압 개념 변화에 미치는 영향)

  • Kim, Jong-Hee;Bae, Ju-Hyeon;Lee, Yong-Seop;Kim, Sang-Dal
    • 한국지구과학회:학술대회논문집
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    • 2004.02a
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    • pp.2-12
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    • 2004
  • The purpose for this study is to inquire into the effects of teaching methods in the class on the conceptual change of atmospheric pressure for middle school students. After analyzing the concept of atmospheric pressure in the middle school science textbooks on the present 7th Curriculum, classes were performed adopting classified Method A and Method B. For Method A, the textbook used that explains the concept in the view of weight. For Method B, the textbook used approaching to the concept in the views of molecular movement as well as of weight. This study consists of four classes in the third grade students of middle school in Busan, which were divided into the Method A group and the Method B group. The result of the study carried out pre-post each of these classes on the learning achievement and on the conceptual change of atmospheric pressure. The result of this study were as follows: First, the effect on the learning achievement was displayed the average score of the Method B was showing meaningful difference comparing to the Method A. Second, the effect on the conceptual change measured by verifying the score for the difference among the averages for each sub-scale three out of four conceptual factors, 'the direction of atmospheric influence and the reason', 'the principle of atmospheric action' and 'the atmospheric changes by the temperature rise on the surface of the earth and the reason', showed meaningful improvement. But, the one left factor, 'the distribution of atmospheric pressure by altitudes and the reason', displayed no meaningful difference. Third, The concept of atmospheric pressure is better defined as the pressure created by the movement of air particles, in the view of kinetic theory of gas, rather than explained by the notion of the weight of air.

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