• Title/Summary/Keyword: Kinematic Parameter

Search Result 154, Processing Time 0.022 seconds

A Study on a Quantitative Method in Estimating Forest Effects for Streamflow Regulation (II) - Mainly Dealing with Application of Coefficient for Slope Roughness - (삼림이수기능(森林理水機能)의 정량적(定量的) 평가방법(平價方法)에 관한 연구(硏究)(II) - 조도계수(粗度係數)의 응용(應用)을 중심(中心)으로 -)

  • Lee, Heon Ho
    • Journal of Korean Society of Forest Science
    • /
    • v.81 no.4
    • /
    • pp.337-345
    • /
    • 1992
  • In this research, a kinematic wave model was applied for the runoff analysis, Regulation of streamflow was estimated by the calibration of roughness coefficient as a parameter. The data analyzed were obtained from Ananomiya and Shirasaka experimental basins at Tokyo University Forest in Aichi. Estimation methods and characteristics of roughness coefficient as a evaluation method of hydrological function of forest are summarized as follows ; 1. Roughness coefficient($N_s$) indicates the resistance of hillslope to the flowing water of surface runoff. There exists an hypothesis that resistance of hillslope to flowing water increase with the growth forest and development of the $A_o$ layer. 2. Roughness coefficient($N_s$) was estimated by the parameter when the stream direct runoff was calculated by using the kinematic wave. 3. Secular change of '$N_s$' in ananomiya has a curve which has an upper limit and increases exponentially near the limit. The curve quickly increased from 1935 to 1945 when results of afforestation for erosion control were thought to be effective. On the other hand, slight increase of '$N_s$' in Shirasaka indicates that there was not such a big change in the surface of soil layer. 4. The increase of '$N_s$' was related with decrease of direct runoff and increase of base flow. It was recognized that the rate of direct runoff decreased with the improvement of forest physiognomy and the rate of base flow was increased. But absolute value of water runoff per one storm decreased in chronological order.

  • PDF

Association study analysis of phospholipase C zeta gene polymorphism forsperm motility and kinematic characteristics in liquid semen of Boar (Phospholipase C zeta 유전자의 유전적다형성과 돼지 액상정액의 운동학적 특성과의 연관성 분석)

  • Jeong, Yong-dae;Jeong, Jin-Young;Sa, Soo-Jin;Kim, Ki-Hyun;Cho, Eun-Seok;Yu, Dong-Jo;Park, Sungk-won;Jang, Hyun-Jun;Woo, Jae-Seok;Choi, Jung-Woo
    • Journal of Embryo Transfer
    • /
    • v.31 no.3
    • /
    • pp.293-297
    • /
    • 2016
  • For evaluating the boar semen quality, sperm motility is an important parameter because the movement of sperm indicates active metabolism, membrane integrity and fertilizing capacity. Phospholipase C zeta (PLCz) is important enzyme in spermatogenesis, but the effect has not been confirmed in pigs yet. Therefore, this study was aimed to analyze their association with sperm motility and kinematic characteristics. DNA samples from 124 Duroc pigs with records of sperm motility and kinematic characteristics [total motile spermatozoa (MOT), curvilinear velocity (VCL), straight-line velocity (VSL), the ratio between VSL and VCL (LIN), amplitude of lateral head displacement (ALH)] were subjected. A SNP in non-coding region of PLCz g.158 A > C was associated with MOT (p < 0.05), VCL (p < 0.01), LIN (p < 0.01) and ALH (p < 0.05) in Duroc population. Therefore, we suggest that the intron region of the porcine PLCz gene may be used as a molecular marker for Duroc boar semen quality, although its functional effect was not defined yet. Whether the association is due to the candidate gene or not require further verification. Thus, it will be of interest to continue association studies in the regions surrounding those genes.

Kinematic Analysis of Lower Extremities during Stairs and Ramp Climbing with Older Adults (노인의 계단과 경사로 오르기 동안 하지의 운동학적 분석)

  • Han, Jin-Tae;HwangBo, Gak
    • Korean Journal of Applied Biomechanics
    • /
    • v.19 no.3
    • /
    • pp.435-448
    • /
    • 2009
  • The purpose of this study was to investigate the kinemaitc gait parameter of lower extremities with different gait conditions(level walking, stairs, ramp) in old adults. Fourteen healthy older adults participated in this study and kinematic data were measured using 3D motion analysis system(Vicon, Oxford Metrics, England). Statistical analysis was used one-way ANOVA to know the difference of lower extremities angle at each gait phase with a different gait conditions. In sagittal plane, pelvic anterior tilt increased in stairs and ramp climbing and hip and knee flexion increased in stairs climbing but ankle dorsiflexion increased in ramp climbing. In frontal plane, pelvic was up in stairs and hip abduction and adduction more changed in stairs climbing than level walking. Knee varus and ankle inversion increased in stair climbing. In horizontal plane, pelvic internal rotation increased in stairs and ramp climbing and knee internal rotation increased in stairs climbing but ankle external rotation increased in stairs climbing. This results was shown that the stairs and ramp climbing changed the kinematic gait parameters of lower extremities in healthy old adults.

A Study on the Handling Performances of a Large-Sized Bus with the Change of Rear Suspension Geometry (후륜 현가장치 지오메트리 변화에 따른 대형 버스의 조종 안정성 연구)

  • 서권희;국종영;천인범
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.9 no.4
    • /
    • pp.176-183
    • /
    • 2001
  • It is difficult to find out the kinematic characteristics of a vehicle suspension without the usage of CAE software. The application of CAE software into suspension kinematics and dynamics yields the more precise knowledge on the chassis design. In this study, the influence of the suspension geometry on the handling performances of a large-sized bus is investigated using the DADS software. The front and rear suspension of a large-sized bus are a rigid axle suspension with the four control links. The elastokinematic analysis is performed to evaluate the roll characteristics of the front and rear suspension. The elastokinematic responses are evaluated in terms of the roll center height and roll steer for various geometric parameters. The roll center height is mainly dependent on the vertical displacement of a panhard rod and the vertical displacements of lower control links affect the roll steer of a rear suspension. The parameter study with the change of rear suspension geometry is conducted to investigate the vehicle handling performances. This parameter study shows that the vertical displacement and orientation of a panhard rod influence the handling performances of a large-sized bus significantly.

  • PDF

Optimal fiber volume fraction prediction of layered composite using frequency constraints- A hybrid FEM approach

  • Anil, K. Lalepalli;Panda, Subrata K.;Sharma, Nitin;Hirwani, Chetan K.;Topal, Umut
    • Computers and Concrete
    • /
    • v.25 no.4
    • /
    • pp.303-310
    • /
    • 2020
  • In this research, a hybrid mathematical model is derived using the higher-order polynomial kinematic model in association with soft computing technique for the prediction of best fiber volume fractions and the minimal mass of the layered composite structure. The optimal values are predicted further by taking the frequency parameter as the constraint and the projected values utilized for the computation of the eigenvalue and deflections. The optimal mass of the total layered composite and the corresponding optimal volume fractions are evaluated using the particle swarm optimization by constraining the arbitrary frequency value as mass/volume minimization functions. The degree of accuracy of the optimal model has been proven through the comparison study with published well-known research data. Further, the predicted values of volume fractions are incurred for the evaluation of the eigenvalue and the deflection data of the composite structure. To obtain the structural responses i.e. vibrational frequency and the central deflections the proposed higher-order polynomial FE model adopted. Finally, a series of numerical experimentations are carried out using the optimal fibre volume fraction for the prediction of the optimal frequencies and deflections including associated structural parameter.

Efficient determination of combined hardening parameters for structural steel materials

  • Han, Sang Whan;Hyun, Jungho;Cho, EunSeon;Lee, Kihak
    • Steel and Composite Structures
    • /
    • v.42 no.5
    • /
    • pp.657-669
    • /
    • 2022
  • Structural materials can experience large plastic deformation under extreme cyclic loading that is caused by events like earthquakes. To evaluate the seismic safety of a structure, accurate numerical material models should be used. For a steel structure, the cyclic strain hardening behavior of structural steel should be correctly modeled. In this study, a combined hardening model, consisting of one isotropic hardening model and three nonlinear kinematic hardening models, was used. To determine the values of the combined hardening model parameters efficiently and accurately, the improved opposition-based particle swarm optimization (iOPSO) model was adopted. Low-cycle fatigue tests were conducted for three steel grades commonly used in Korea and their modeling parameters were determined using iOPSO, which was first developed in Korea. To avoid expensive and complex low cycle fatigue (LCF) tests for determining the combined hardening model parameter values for structural steel, empirical equations were proposed for each of the combined hardening model parameters based on the LCF test data of 21 steel grades collected from this study. In these equations, only the properties obtained from the monotonic tensile tests are required as input variables.

A study of sea level measurement using GPS buoy (GPS 부의를 이용한 해수면 관측에 관한 연구)

  • Park, Un-Yong;Oh, Chang-Soo;Lee, Dong-Rak;Hong, Jung-Soo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2007.04a
    • /
    • pp.85-88
    • /
    • 2007
  • Sea level fluctuation present a direct influence to those who live near the coast. The importance of monitoring sea level is evident. Therefore, various techniques have been employed for sea level measurements such as the coastal water level gauges, satellite altimetry and GPS buoy. Especially, GPS buoys have been used to measure water levels, atmospheric parameter and other physical conditions in sea, tide correction, the altimeter range calibration, ocean environment. In this paper, we will mainly concentrate on the kinematic technique for GPS buoy to measure the sea level. A test was carried out to test the method proposed in this paper, which made use of a GPS buoy equipped to monitor the sea level in Busan. We have executed to analysis about applications of GPS buoy.

  • PDF

FL Deadzone Compensation of a Mobile robot (이동로봇의 퍼지 데드존 보상)

  • Jang, Jun Oh
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.4
    • /
    • pp.191-202
    • /
    • 2013
  • A control structure that makes possible the integration of a kinematic controller and a fuzzy logic (FL) deadzone compensator for mobile robots is presented. A tuning algorithm is given for the fuzzy logic parameters, so that the deadzone compensation scheme becomes adaptive, guaranteeing small tracking errors and bounded parameter estimates. Formal nonlinear stability proofs are given to show that the tracking error is small. The fuzzy logic deadzone compensator is implemented on a mobile robot to show its efficacy.

Transient response of 2D functionally graded beam structure

  • Eltaher, Mohamed A.;Akbas, Seref D.
    • Structural Engineering and Mechanics
    • /
    • v.75 no.3
    • /
    • pp.357-367
    • /
    • 2020
  • The objective of this article is investigation of dynamic response of thick multilayer functionally graded (FG) beam under generalized dynamic forces. The plane stress problem is exploited to describe the constitutive equation of thick FG beam to get realistic and accurate response. Applied dynamic forces are assumed to be sinusoidal harmonic, sinusoidal pulse or triangle in time domain and point load. Equations of motion of deep FG beam are derived based on the Hamilton principle from kinematic relations and constitutive equations of plane stress problem. The numerical finite element procedure is adopted to discretize the space domain of structure and transform partial differential equations of motion to ordinary differential equations in time domain. Numerical time integration method is used to solve the system of equations in time domain and find the time responses. Numerical parametric studies are performed to illustrate effects of force type, graduation parameter, geometrical and stacking sequence of layers on the time response of deep multilayer FG beams.

Development of a coupled tendom driven robot hand

  • Choi, H.R.;Lee, Y.T.;Kim, J.H.;Chung, W.K.;Youm, Y.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1993.10b
    • /
    • pp.185-190
    • /
    • 1993
  • The POSTECH Hand adopting coupled tendon driven technique with planar two fingers is developed. The hand is designed to emulate principal motions of the human hand which has two and three joints respectively. Its kinematic parameters are determined through a parameter optimizing technique to aim at improving the isotropy of fingertip motions with new criterion functions of design. For the control of the hand, tension and torque control algorithms are developed. Based on the virtual stiffness concept, we develop the stiffness control method of a grasped object with redundant finger mechnism and investigate experimentally.

  • PDF