• Title/Summary/Keyword: Inclination Angle

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Dynamic Characteristic Analysis of Trapezoidal Cantilever Plates Undergoing Translational Acceleration (가속을 받는 사다리꼴 외팔 평판의 동특성 해석)

  • 임홍석;유홍희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.268-273
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    • 2002
  • A modeling method for the dynamic characteristic analysis of a translationally accelerated trapezoidal cantilever plate is presented in this paper. The equations of motion for the plate are derived and transformed into a dimensionless form. The effects of the inclination angles and the acceleration on the vibration characteristics of the plate are investigated. Incidentally, natural frequency loci veering and associated mode shape variations are observed and discussed

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Disk Galaxy Warp Formation via Close Encounters

  • Kim, Jeong-Hwan;Peirani, Sebastien;Yun, Ki-Yun;Bae, Hyun-Jin;Yoon, Suk-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.58.1-58.1
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    • 2011
  • We present our N-body simulation study on the disk galaxy warp formation via close encounters. Using a publicly available code Gadget2, we investigate morphological and kinematical structures of disk galaxies while the galaxies are undergoing fly-by encounters with adjacent dark matter halos. In this study, we find that warps can be excited by impulsive encounters and sustained for a few billion years. Most of the warps from the simulation show inclination angles that are comparable to the observations. The creation of warps, their inclination and their lifetimes are governed primarily by the following three parameters: the impact parameter (the minimum distance between two halos), the mass ratio between two galaxies, and the incoming angle of the intruder. We discuss pros and cons about our alternative scenario in comparison with existing explanations.

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An Experimental Study on the Natural Convection from the Isothermal Square Beam with an Adiabatic Wall (단열벽(斷熱壁)에 부착(附着)된 등온사각(等溫四角)비임에서의 자연대류(自然對流) 열전달(熱傳達))

  • Lee, C.J.;Park, J.L.;Kwon, S.S.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.17 no.1
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    • pp.65-73
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    • 1988
  • Steady laminar natural convection heat transfer from an isothermal square beam with adiabatic wall has been studied for various inclination angles of the wall and Rayleigh numbers by using Mach-Zehnder Interferometer in air. The different temperature and fluid fields were obtained as the inclination angle changes showing the effects of the ascending heated fluid and the adiabatic wall. The maximum total mean Nusselt number was found at ${\theta}=45^{\circ}$.

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Development of Cooling System for Electronic Devices using Oscillating Capillary Tube Heat Pipe (진동세관형 히트파이프를 이용한 전자기기 냉각에 대한 연구)

  • Kim Jong-Soo;Ha Soo-Jung
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.4
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    • pp.436-442
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    • 2005
  • Rapid development of electronic technology requires small size, high density packaging and high power of electronic devices. In this paper, characteristics on oscillating heat pipe according to operating conditions (environment temperature, charging ratio of working fluid, inclination) based on experimental study was investigated From the experimental results $25^{\circ}C$(environment temperature) R-141b (working fluid) $40\%$ (charging ratio) was best performace at others of inclination angle and the top heating mode of OCHP performed $80\%$ efficiency of the bottom heating mode.

Deburring experiment in drilling hole on the inclined exit surface (경사진 출구면에 발생한 버의 제거를 위한 디버링 공구의 효율적 운용)

  • Kim B.K.;Lee K.U.;Park J.W.;Hong S.I.;Ko S.L.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.773-776
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    • 2005
  • An Experiment was carried out to study deburring in frilling hole on the Inclined exit surface. Two different deburring tools, exit surface angles, materials and cutting conditions were selected to check their performance using CNC machining center. In deburring operation, there are not only flat exit surfaces but also inclined exit surfaces which is described as inclination angle. Inclination of exit surface causes a quite different burr formation when comparing with flat surface. Deburring characteristics are analyzed according to the deburring tools and cutting conditions. Several strategies for a effective deburring on inclined exit surface were proposed.

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Natural Convection in the Annulus between Concentric Inclined Cylinders (경사진 동심원통 사이의 환상공간에서 자연대류 열전달)

  • Kim, Chan-Won;Kwon, Sun-Sok
    • Solar Energy
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    • v.7 no.1
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    • pp.53-60
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    • 1987
  • Natural convection in the annulus between concentric inclined cylinders has been studied by the numerical analysis. Governing equations are numerically solved by means of successive over-relaxation methods for a range in orientation from horizontal to vertical. It is found that flow patterns can also be observed the co-axial double spiral. As the angle of inclination is increased, the center of the eddy is shifted into the lower part of annulus and flow structure is apparently changed. In the present study, the maximum local Nusselt numbers for the inner and outer walls at the vertical cylinder increase more than those at the horizontal cylinder by 71%, 42% respectively. Consequently the effect of inclination on the heat transfer is considerably large.

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Discrepancies in Soft Tissue Profile of Patients for Orthognathic Surgery between Preoperative Lateral Facial Photograph, Lateral Cephalogram and Supine Position on Operation Table

  • Jung, Young-Eun;Yang, Hoon-Joo;Hwang, Soon-Jung
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.34 no.3
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    • pp.180-185
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    • 2012
  • Purpose: An accurate preoperative analysis of the patient is essential in orthognathic surgery in order to acquire superior results. In profile, the location of the chin's position may change according to the neck's inclination. This may ultimately affect the amount of surgical movement. During acquisition of cephalometric radiographs, or in supine position, there is a discrepancy in the neck's inclination. This means that there are also various discrepancies between the actual profile and the various preoperative profile images. In the clinical situation, the decision in performing genioplasty usually lies in the analysis of the patient's profile on the operating table at the final stages of orthognathic surgery. This study aims to analyze the different preoperative profile images and to compare their discrepancies. Methods: Fifty eight patients undergoing orthognathic surgery were chosen. These patients were divided into three groups according to angle's classification of malocclusion, as class I, II or III. The right profile of these patients in centric occlusion was taken in natural head position (NHP). This was set as the 'actual profile image.' Another right profile image was taken on the operating table after insertion of the nasotracheal intubation and with muscle relaxants in effect. This was also taken in centric occlusion. The angle (denoted 'A') between the soft tissue glabella-pognion and the true vertical plane was found in the above-mentioned profile images and in the cephalometric radiographs. The differences of these values were analyzed. Results: There were differences in Angle 'A' in all of the preoperative images. These values were however, not statistically significant. Conclusion: In order to gain an esthetic profile during orthognathic surgery, the NHP is shown to be the most reliable position. Images reproducing such head positions should be used in the treatment planning process.

THE BEAM POINTING OF COMMUNICATIN SATELLITE IN GEOSYNCHRONOUS INCLINED ORBIT (궤도경사각을 가진 통신위성의 빔 포인팅에 대한 연구)

  • 김방엽;최규홍
    • Journal of Astronomy and Space Sciences
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    • v.12 no.1
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    • pp.112-122
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    • 1995
  • We assume that the KOREASAT fails the entry of the geostationary orbit due to the error at the apogee kick motor firing. A simulation is done for the satellite that has a geosynochronous orbit with a non-zero degree inclination angle due to the failure at the apogee kick motor firing caused by the unbalance of the fuel storage and the spin of the thrust vector, etc. We analyzed the evolution of the orbit using the perturbation theory and calculated the changes of the eccentricity and the inclination. WHen a communication satellite has the figure eight trajectory, the beam point also traces the satellite. In this paper, We develope an algorithm to attack the above problem by stabilizing the beam point using the adjustment of the roll angle of the satellite. The spin action on the polarization plane that occurs when a satellite passes the ascending node and descending node affects the efficiency of the communication a lot, so we did another simulation for the better yaw angle adjustment for the KOREASAT to reduce the spin actino on the polarization plane.

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A SOFT TISSUE ANALYSIS ON FACIAL ESTHETICS OF KOREAN YOUNG ADULTS (한국인 성인의 악안면 연조직의 심미적 안모형태 분석에 관한 연구)

  • Baek, Seung-Hak;Yang, Won-Sik
    • The korean journal of orthodontics
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    • v.21 no.1 s.33
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    • pp.131-170
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    • 1991
  • This study was designed to analyze morphological characteristics of Korean young adults, norms and standard deviation of variables, sexual differences, correlationship between each area of face and correlationship between hard tissue and soft tissue. The primary sample consisted of 45 males and 57 females who were early and middle twenties and had acceptable profile, no history of previous orthodontic treatment, absence of remarkably large overjet and overbite, full complement of permanent teeth, Class I skeletal and dental relationships and good vertical facial proportions. Their cephalograms were analyzed morphologically with a computer morphometrics. Then the final sample - 25 males and 38 females - were selected within 1 S.D. of E-line, ANB, P/A facial height ratio, Interincisal angle, L1 to A-Pog, ODI and APDI. The results of the study were as follows: 1 In the form and proportion of facial skeleton there were no significant differences between males and females, but in the size males were larger than females. 2. The dental protrusion patterns had no significant sexual difference and no significant correlationship between protrusion of upper lip and inclination of upper incisor. But mentolabial angle had positively correlated with interincisal angle and negatively with inclination of upper and lower incisor. 3. In the relationship between nose and soft-tissue profile, males were larger than females in nasal length, height and angular measurements. 4. In analysis of soft-tissue profile, males were larger than females in the length and thickness. In the angular measurements and proportion of soft-tissue profile, there were no significant differences between males and females.

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A Study on the Improvement of the Condensation Heat Transfer Performance of the Helical Grooved and Plain Thermosyphons (나선 그루브와 평관형 열사이폰의 응축열전달 성능 향상에 관한 연구)

  • Han, K.I.;Park, J.U.;Cho, D.H.
    • Journal of Power System Engineering
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    • v.10 no.2
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    • pp.47-53
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    • 2006
  • This study concerns the performance of condensation heat transfer in plain and grooved thermosyphons. Distilled water, methanol, ethanol have been used as the working fluids. In the present work, a copper tube of the length of 1200mm and 14.28mm of inside diameter is used as the container of the thermosyphon. Each of the evaporator and the condenser section has a length of 550mm, while the remaining part of the thermosyphon tube is adiabatic section. A study was carried out with the characteristics of heat transfer of the thermosyphon 50, 60, 70, 80, 90 helical grooves in which boiling and condensation occur. The liquid filling as the ratio of working fluid volume to total volume of thermosyphon, the kinds of working fluid, the inclination angle, grooves and operating temperature have been used as the experimental parameters. The experimental results show that the number of grooves, the amount of the working fluid, the kind of working fluid, angle of inclination angle are very important factors for the operation of thermosyphon. The maximum heat transfer was obtained when the liquid fill was about 20 to 25 % of the thermosyphon volume. The relatively high rates of heat transfer have been achieved in the thermosyphon with grooves. The helical grooved thermosyphon having 70 to 80 grooves in water, 60 to 70 grooves in methanol and 70 to 80 grooves in ethanol shows the best heat transfer coefficient in both condensation.

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