• Title/Summary/Keyword: 윙

Search Result 49, Processing Time 0.03 seconds

A Study on the Unsteady Flow Characteristics of a Delta Wing by 3-D Stereo PIV (3-D Stereo PIV에 의한 비정상 델타윙 유동특성에 대한 연구)

  • Kim, Beom-Seok;Lee, Hyun;Kim, Jeong-Hwan;Lee, Young-Ho
    • Proceedings of the KSME Conference
    • /
    • 2004.04a
    • /
    • pp.1672-1677
    • /
    • 2004
  • Leading edge extension(LEX) in a highly swept shape applied to a delta wing features the modem air-fighters. The LEX vortices generated upon the upper surface of the wing at high angle of attack enhance the lift force of the delta wing by way of increased negative suction pressure over the surfaces. The present 3-D stereo PIV includes the Identification of 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criterion and so on. A delta wing model with or without LEX was immersed in a circulating water channel. Two high-resolution, high-speed digital cameras($1280pixel{\times}1024pixel$) were used to allow the time-resolved animation work. The present dynamic stereo PIV represents the complicated vortex behavior, especially, in terms of time-dependent characteristics of the vortices at given measuring sections. Quantities such as three velocity vector components, vorticity and other flow information can be easily visualized via the 3D time-resolved post-processing to make the easy understanding of the LEX effect or vortex emerging and collapse which are important phenomena occurring in the field of delta wing aerodynamics.

  • PDF

An Analysis of Research Trends in Computational Thinking using Text Mining Technique (텍스트 마이닝 기법을 활용한 컴퓨팅 사고력 연구 동향 분석)

  • Lee, Jaeho;Jang, Junhyung
    • Journal of The Korean Association of Information Education
    • /
    • v.23 no.6
    • /
    • pp.543-550
    • /
    • 2019
  • In 2006, Janet Wing defined computational thinking and operated SW education as a formal curriculum in the UK in 2013. This study collected related research papers by using computational thinking, which has recently increased in importance, and analyzed it using text mining. In the first, CONCOR analysis was conducted with the keyword of computational thinking. In the second, text mining of the components of computational thinking was selected by the repr23esentative academic journals at domestic and foreign. As a result of the two-time analysis, first, abstraction, algorithm, data processing, problem decomposition, and pattern recognition were the core of the study of computational thinking component. Second, research on convergence education centered on computational thinking and science and mathematics subjects was actively conducted. Third, research on computational thinking has been expanding since 2010. Research and development of the classification and definition of computational thinking and components and applying them to education sites should be conducted steadily.

The effect of taping intervention applied to the diaphragm on the performance of anaerobic exercise in 30 seconds: pilot study (횡격막에 적용된 테이핑 처치가 30초간의 무산소 운동수행력에 미치는 영향: pilot study)

  • Choi, Hyun-Seok;Cho, Il-Young
    • Journal of Digital Policy
    • /
    • v.1 no.1
    • /
    • pp.7-13
    • /
    • 2022
  • The purpose of this study was to investigated the effect of taping intervention applied to the diaphragm on the anaerobic performance in 30 seconds. 18 healthy college students were randomly divided into experimental group(KT=9) and control group(Sham=9). In both groups, pre and post measurement was performed by wingate test, and post measurement was performed with taping application after a week rest. The statistics between two groups on the rate of change pre and post were analyzed through Mann-Whitney U test. Statistically, it showed that only the average power(AP) of control group was significantly different. This means that diaphragmatic taping did not affect the performance of anaerobic exercise for 30 seconds. However, considering the increase in aerobic metabolism during long-term anaerobic exercise longer than 30 seconds, further studies on anaerobic exercise performance within various time ranges are needed.

Comparison of Chemical Composition in Different Portions of Domestic Broiler Meat (국내 유통 닭고기의 부분육별 화학적 특성 조사)

  • 채현석;조수현;박범영;유영모;김진형;안종남;이종문;김용곤;윤상기
    • Korean Journal of Poultry Science
    • /
    • v.29 no.1
    • /
    • pp.51-57
    • /
    • 2002
  • This study was conducted to investigate the chemical composition in different portions of domestic broiler meat. The broilers were obtained from slaughtering house, where the scale of slaughtering was more than 50,000 heads per day. The carcasses were separated by cutting into 7 portions such as wing, drumstick, drummette, breast, skin, thigh, and tenderloin. Moisture contents of drummette and thigh were 73.37% and 73.19%, whereas those of drumstick and wing were 75.65% and 75.76%, respectively. The portions of breast parts contained 4.20% higher protein, but 4.17% lower fat than those of leg parts. Overall mineral contents were relatively high for thigh when compared with breast. The content of Fe was higher by 1.8 folds(7.3ppm) in thigh than that in tenderloin(4.0ppm) and the content of Zn was higher in drummette than that in tenderloin. For amino acid compositions, the tenderloin contained more glutamic acid and methionine than the other portion meats. The portions of drumstick(3.97mg/g) and thigh (3.24mg/g) were higher in collagen contents than the other Parts. Wing portion had the lowest collagen content of 2.64mg/g, which was due to the removal of its skin.

General Steady-State Shape Factors in Analyzing Slug Test Results to Evaluate In-situ Hydraulic Conductivity of Vertical Cutoff Wall (순간변위시험(slug test)시 연직차수벽의 현장투수계수를 산정하기 위한 형상계수 연구)

  • Lim, Jee-Hee;Lee, Dong-Seop;Nguyen, Thebao;Choi, Hang-Seok
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.10
    • /
    • pp.105-116
    • /
    • 2011
  • No analytical solution exists for evaluating in-situ hydraulic conductivity of vertical cutoff walls by analyzing slug test results. Recently, an analytical solution to interpret slug tests has been proposed for a partially penetrated well in an aquifer. However, this analytical solution cannot be directly applied to the cutoff wall because the solution has been developed exclusively for an infinite aquifer instead of a narrow cutoff wall. To consider the cutoff wall boundary conditions, the analytical solution has been modified in this study to take into account the narrow boundaries by introducing the imaginary well theory. Two boundary conditions are considered according to the existence of filter cakes: constant head boundary and no flux boundary. Generalized steady-state shape factors are presented for each geometric condition, which can be used for evaluating the in-situ hydraulic conductivity of cutoff walls. The constant head boundary condition provides higher shape factors and no flux boundary condition provides lower shape factors than the infinite aquifer, which enables to adjust the in-situ hydraulic conductivity of the cutoff wall. The hydraulic conductivities calculated from the analytical solution in this paper give about 1.2~1.7 times higher than those from the Bouwer and Rice method, one of the semi-empirical formulas. Considering the compressibility of the backfill material, the analytical solution developed in this study was proved to correspond to the case of incompressible backfill materials.

A Study on the Advance Effect of Hitting Sense in Shooting Game -Center for 'the Beetlewing' and '1945 Plus'- (슈팅게임에서의 타격감 향상 효과에 관한 연구 -'비틀윙'과 '1945플러스'를 중심으로-)

  • 김남훈;김태완
    • Journal of Korea Multimedia Society
    • /
    • v.7 no.2
    • /
    • pp.223-230
    • /
    • 2004
  • A shooting game is all game genres that hit targets through shooting. It include a lot of genres from a flying shot of game room to a personal shooting action game. In this point, a shooting game was regarded it as the origin of all game and it was developed from the early days of game. At present we can meet it in an electronic game room or personal computer, and mobile phone etc.. The popularity of shooting game caused to take aim by simple system, interface, and speedy play. Also it was enticed everyone to enjoy it easily. A shooting games is worked from old like ways until recently and a process of playing game is intuitive than another game. Therefore it popular with a PC player as well as persons of all levels. Beginners can train this game easily through direction such as control way of object, advent way of enemy aircraft and scroll way of background. But as an usability of working and controlling game, beginners of game development can pass over a shooting sense that shout and hit basically. And after design, they will feel that cannot convey realistic effect and thrill etc.. At a result, hitting sense happens to graphic elements and sound. Therefore a measure of effect on these elements is started from analysis of good shooting game. This study was to focus on the advance effect of hitting sense in shooting game through analysis centered for 'the Beetlewing' and '1945 Plus'.

  • PDF

Change of fracture mode of orthodontic resin bracket wings under water immersion and thermocycling (침수 및 열순환에 따른 레진브라켓 wing의 파절강도 변화)

  • Son, Ji-Hyeong;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
    • /
    • v.30 no.4 s.81
    • /
    • pp.475-481
    • /
    • 2000
  • The purpose of this study was to evaluate the effect of oral environment on the strength of resin bracket wings by comparing fracture mode according to water immersion and thermocycling. Seventy-five resin brackets(Spirit MB, Ormco, California) were divided into three groups and treated for six months as follows; (1) untreated, (2) water immersion in distilled water at $37^{\circ}C$, (3) water immersion in distilled water at $37^{\circ}C$ with total 2,100 times of thermocycling taken 350 times each month. Fracture mode of the wing was tested on universal testing machine. In addition to resin brackets, 25 metal brackets were used as controls. Through the statistical analyses, following results were obtained. 1. Resin bracket wings showed significantly lower fracture strength than metal brackets(p<0.001). 2. Water immersion and water immersion with thermocycling groups showed significantly lower fracture strength than open air condition group(p<0.001). 3. Water immersion with thermocycling group showed significantly lower fracture strength than water immersion group(p<0.001). The above results suggest that the mechanical property of resin bracket wing nay be influenced by oral environment and further research is needed to improve the strength of the wing in the resin bracket.

  • PDF

Surface roughness analysis of ceramic bracket slots using atomic force microscope (원자현미경을 이용한 세라믹 브라켓 슬롯의 표면조도에 대한 연구)

  • Park, Ki-Ho;Yoon, Hyun-Joo;Kim, Su-Jung;Lee, Gi-Ja;Park, Hun-Kuk;Park, Young-Guk
    • The korean journal of orthodontics
    • /
    • v.40 no.5
    • /
    • pp.294-303
    • /
    • 2010
  • Objective: This study was designed to measure the surface roughness at the slot floor of various ceramic brackets. Methods: One kind of stainless steel bracket ($Succes^{(R)}$), two kinds of monocrystalline brackets (Inspire $Ice^{(R)}$, $Perfect^{(R)}$) and two kinds of polycrystalline brackets (Crystalline $V^{(R)}$, $Invu^{(R)}$) were examined. Atomic force microscopy (AFM) was used to measure the surface roughness of each bracket. Data acquisition and processing were performed using $SPIP^{TM}$. Results: The differences in values of Sa, Sq, and Sz in $Invu^{(R)}$ and Inspire $Ice^{(R)}$ were not statistically different from the control group $Succes^{(R)}$. The values of Sa, Sq, and Sz of $Perfect^{(R)}$ and Crystalline $V^{(R)}$ were greater than those of $Succes^{(R)}$. Differences of all the Sa, Sq, and Sz values between $Perfect^{(R)}$ and Crystalline $V^{(R)}$ were not statistically significant. Conclusions: It is concluded that the slot surfaces of $Succes^{(R)}$, Inspire $Ice^{(R)}$, and $Invu^{(R)}$ were smooth compared to those of Crystalline $V^{(R)}$ and $Perfect^{(R)}$.

Study on the Performer's Transference and Mental Borderline in a Performance (공연에서 나타나는 '전이'와 배우의 '심리적 경계'에 관한 연구)

  • Kim, Jong-Gu
    • (The) Research of the performance art and culture
    • /
    • no.25
    • /
    • pp.57-89
    • /
    • 2012
  • The performers preparing for a performance usually experience the process of mental transference, contacting with text (drama) for the first time. It is movement from their everyday life to space in the play, when they try to break the wall between cast and themselves. The transference happens actually at the physical space, such as a dressing room, wing, (place just before appearing at a stage), and a stage (place to contact with audience). Performers keep moving among each psychological and physical space repeatedly, until the performance finishes totally. The transference means moving to each space to another, and the mental borderline means the point of mental change the performers experience during the process of transference. The mental borderline can be guessed to exist through mental aspects the performers feel when they move from each space to another. The most typical example, that shows performer's mental borderline well, is stage fright shown as tension, or anxiety among the variety of aspects. According to a research, the most performers experience that kind of mental aspect just before appearing at a stage. The study on it is already referred by my article.' A Study on Korean Performer's Stage Fright. This study aims at examining the relationship among psychological and physical space the performers experience, mental borderline when transferring and penetrating those spaces, and performer's mental change First, the concept of mental borderline is to be understood totally with preceded research. And the space the performers experience and mental borderline at transference are to be reorganized. Secondly, the area of transference in the process of performance is to be reclassified into physical and mental space. Third, analyzing the actual case of performers experiencing the mental borderline, the diversified use should be searched to make use of mental borderline as a positive element. The psychological symptoms, performers experience in the performance, can have positive consequence beside negative one. The tension occurring at the area of borderline is positive, and it can be the actual borderline for the performers. It will be researched how the performers change at the mental borderline, the state of mind is maintained, and they perform in an overall performance, through the study on the relationship between the transference and the mental borderline. And the stress and concentration caused by stage fright, and shyness will be confirmed, and the positive element of a stage, which is used as various defense mechanism.