• Title/Summary/Keyword: surface inclination

Search Result 275, Processing Time 0.031 seconds

The Effect of Pelvic Inclination on Voice Production in sitting (앉은 자세에서 골반 경사도가 음성에 미치는 영향)

  • Choe, Jeong Hui
    • The Journal of the Convergence on Culture Technology
    • /
    • v.1 no.2
    • /
    • pp.91-95
    • /
    • 2015
  • The purpose of this study was to evaluate the difference voice production, according to the pelvic inclination while in the sitting position. Measure the sound produced(pitch) in three positions with the Praat program. position: anterior tilt position, posterior tilt position, neutral position(seat surface tilted 15 degrees). We found that the mean values of pitch were statistically significant different according to three types of sitting positions (p<0.05). The following result was observed: anterior tilt position > posterior tilt position > neutral position. There was significant difference in the neutral position. This finding suggests that the seat surface inclinations have an effect on speech production. Especially, neutral position may be an effective posture that may help increases the speech production.

Experimental Study of the Ultrasonic Vibration Effects on CHF Occurring on Inclined Flat Surfaces (초음파 진동이 경사진 평판에서의 CHF에 미치는 영향에 대한 실험연구)

  • 정지환;김대훈;권영철
    • Journal of Energy Engineering
    • /
    • v.12 no.2
    • /
    • pp.139-144
    • /
    • 2003
  • Augmentation of CHF by ultrasonic vibration in water pool is experimentally investigated under pool boiling condition. The experiments are carried out using copper coated plates and distilled water. Measurements of CHF on flat plate heated surface were made with and without ultrasonic wave and with variations in inclined angle of the surface and water subcooling. Experimental apparatus consists of a bath, power supply, test section, ultrasonic generator, and data acquisition system. The measurements show that ultrasonic wave enhances CHF and its extent is dependent upon inclination angle as well as water subcooling. The rate of increase in CHF increases with an increase in water subcooling while it decreases with an increase in inclination angle. Visual observation shows that the cause of CHF augmentation is closely related with the dynamic behavior of bubble generation and departure in acoustic field.

Investigation of mechanical behaviour of non-persistent jointed blocks under uniaxial compression

  • Asadizadeh, Mostafa;Moosavi, Mahdi;Hossaini, Mohammad Farouq
    • Geomechanics and Engineering
    • /
    • v.14 no.1
    • /
    • pp.29-42
    • /
    • 2018
  • This paper presents the results of an empirical study in which square rock-like blocks containing two parallel pre-existing rough non-persistent joints were subjected to uniaxial compression load. The main purpose of this study was to investigate uniaxial compressive strength and deformation modulus of jointed specimens. Response Surface Method (RSM) was utilized to design experiments and investigate the effect of four joint parameters, namely joint roughness coefficient (JRC), bridge length (L), bridge angle (${\gamma}$), and joint inclination (${\theta}$). The interaction of these parameters on the uniaxial compressive strength (UCS) and deformation modulus of the blocks was investigated as well. The results indicated that an increase in joint roughness coefficient, bridge length and bridge angle increased compressive strength and deformation modulus. Moreover, increasing joint inclination decreased the two mechanical properties. The concept of 'interlocking cracks' which are mixed mode (shear-tensile cracks) was introduced. This type of cracks can happen in higher level of JRC. Initiation and propagation of this type of cracks reduces mechanical properties of sample before reaching its peak strength. The results of the Response Surface Methodology showed that the mutual interaction of the joint parameters had a significant influence on the compressive strength and deformation modulus.

Performance Improvement of the Horizontal Control System for a Tractor Implement Using Sensor Signal from the Front Axle

  • Ro, Young-Min;Moon, Jun-Hee;Kim, Kyeong Uk
    • Journal of Biosystems Engineering
    • /
    • v.41 no.2
    • /
    • pp.67-74
    • /
    • 2016
  • Purpose: Many tractors have adopted the horizontal control system designed to maintain the three-point mounted implements in horizontal position when they are tilted sideways. The control system rotates the implement in the opposite direction to the inclination of rear axle of the tractor. However, the current control system was found to have poor performance in accuracy and response. A new control system was therefore developed to improve the performance. Methods: The new control system was designed to get the response of the implement to be started earlier by using the tilt information from the front axle of the tractor. By this approach, the rotation of the implement can be adjusted as required to make it horizontal at the expected time, even though the response is slow. The optimal values of the control parameters for the new system were determined by computer simulation and validated by a performance test conducted with an obstacle of 120 mm height on a flat concrete surface. The performance of the control system was evaluated by the root mean square error (RMSE) of the rotation angle of the implement with respect to the actual inclination of the rear axle. Results: The new control system reduced the RMSE of the current control system by 44.6% indicating a high performance improvement. The inclination of the front axle was easily obtained from a sensor mounted on the front axle of the tractor and used as input to the new control system. Conclusions: The method of getting the response of the implement to be started earlier by utilizing the inclination information of the front axle can be applied to improve the performance of the current control system at least cost.

Analysis of Load Capacity and Deformation Behavior of Suction Pile Installed in Sand (모래지반에 근입된 석션파일의 인발저항력 및 변위거동 분석)

  • Kim, You-Seok;Jang, Yeon-Soo
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.11
    • /
    • pp.27-37
    • /
    • 2011
  • A series of centrifuge model tests to investigate the suction pile pullout loading capacity in sand have been performed. The main parameters that affect the pullout loading capacity of a suction pile include the mooring line inclination angle and the padeye position of the suction pile. With respect to the padeye position, the maximum pullout loading capacity is obtained when the padeye position is near 75% of the pile length from the top. The direction of the pile rotation changes when the padeye position reaches somewhere near 50~75% for all mooring line inclination angles. The translation displacement of suction pile to develop the time of maximum pullout loading capacity decreased as the mooring line inclination angle increased. In addition, the vertical displacements of the center of a suction piles for all cases appeared to develop toward the ground surface.

A Convergent Investigation on Flow Analysis by Type of Turbine Blade of Fluid Clutch (유체클러치 터빈 날개의 유형별 유동해석에 대한 융합연구)

  • Oh, Bum-Suk;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
    • /
    • v.11 no.3
    • /
    • pp.195-200
    • /
    • 2020
  • In this study, the flow analyses were performed on the fluid clutch turbine blade shapes of models 1, 2 and 3, with eight turbine blades tilted at 45 °, 40 °, and 35 ° angles on the propulsion shaft, respectively. The larger the angle of inclination on the propulsion shaft, the higher the flow pressure among the flow models after the back of the turbine blades. On the other hand, the smaller the angle of inclination on the propulsion shaft of the turbine wing, the lower the flow rate. It can be seen that the smaller inclination angle of the turbine blade surface on the propulsion shaft, i.e., the wing shape close to perpendicular to the flow of fluid, is more suitable for efficiently connecting and disconnecting the fluid clutch. By applying the flow analysis by type of turbine blade of fluid clutch,the study result at this paper is considered to be favorable as the convergent research material which can apply the aesthetic design.

Three Dimensional Finite Element Inverse Analysis of Rectangular Cup and S-Rail Forming Processes using a Direct Mesh Mapping Method (직접 격자 사상법을 이용한 직사각컵 및 S-Rail 성형공정의 3차원 유한요소 역해석)

  • Kim S. H.;Huh H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2001.10a
    • /
    • pp.81-84
    • /
    • 2001
  • An inverse finite element approach is employed for more capability to design the optimum blank shape from the desired final shape with small amount of computation time and effort. In some drawing or stamping simulation with inverse method, it is difficult to apply inverse scheme due to the large aspect ratio or steep vertical angle of inclination. The reason is that initial guesses are hard to make out with present method for those cases. In this paper, a direct mesh marring scheme to generate initial guess on the sliding constraint surface described by finite element patches is suggested for one step inverse analysis to calculate initial blank shape. Radial type mapping is adopted for the simulation of rectangular cup drawing process with large aspect ratio and parallel type mapping for the simulation of S-Rail forming process with steep vertical angle of inclination.

  • PDF

AUTOMATIC LEVELING CONTROL SYSTEM FOR COMBINE

  • Lee, S. S.;K. S. Oh;H. Hwang;Park, D. Y.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 2000.11c
    • /
    • pp.684-689
    • /
    • 2000
  • In harvesting rice and barley using combine, the inclination of the body caused by the irregular surface condition of the field and the soil sinking from the unbalanced weight during the grain collection used to make harvesting operation difficult and even impossible. To overcome such a problem, automatic leveling control system for a combine has been developed and tested. The system was composed of the sensor for measuring left and right inclination of the combine chassis and the hydraulic control system. The adaptability of the control system was investigated by analyzing system response in time domain. And the limit angle of the leveling control was set up to be +/- 7$^{\circ}$. The proposed control and hydraulic power system was implemented to the prototype combine. The prototype combine was designed and built as a separable structure with chassis and track. This paper shows results of the leveling performance tested in the laboratory and the grain field.

  • PDF

A Study on the Analysis of Solar Radiation on Inclined Surfaces for the Installation of PV Systems (PV시스템 설치를 위한 경사면 태양광에너지 분석에 관한 연구)

  • Jo, Dok-Ki;Kang, Young-Heack
    • Journal of the Korean Solar Energy Society
    • /
    • v.27 no.1
    • /
    • pp.11-17
    • /
    • 2007
  • The amount of incident rays over inclination according to direction has been widely utilized as important data in installing photovoltaic systems. This is because the performance of the photovoltaic systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized photovoltaic systems will be provided for designers and employees working in the photovoltaic module related industries.

VARIATION OF LOCAL POOL BOILING HEAT TRANSFER COEFFICIENT ON 3-DEGREE INCLINED TUBE SURFACE

  • Kang, Myeong-Gie
    • Nuclear Engineering and Technology
    • /
    • v.45 no.7
    • /
    • pp.911-920
    • /
    • 2013
  • Experimental studies on both subcooled and saturated pool boiling of water were performed to obtain local heat transfer coefficients on a $3^{\circ}$ inclined tube of 50.8 mm diameter at atmospheric pressure. The local values were determined at every $45^{\circ}$ from the very bottom to the uppermost of the tube periphery. The maximum and minimum local coefficients were observed at the azimuthal angles of $0^{\circ}$ and $180^{\circ}$, respectively, in saturated water. The locations of the maxima and the minima were dependent on the inclination angle of the tube as well as the degree of subcooling. The major heat transfer mechanisms were considered to be liquid agitation generated by the sliding bubbles and the creation of big size bubbles through bubble coalescence. As a way of quantifying the heat transfer coefficients, an empirical correlation was suggested.