• 제목/요약/키워드: linear parameters

검색결과 3,833건 처리시간 0.028초

선형저수지 모형의 매개변수연구 (A study on Parameters of Linear reservoir models)

  • 고재웅;서영제
    • 물과 미래
    • /
    • 제20권3호
    • /
    • pp.229-235
    • /
    • 1987
  • The purpose of this study is to estimate the parameters of linear reservoir models in order to derive the Instantaneous unit hydrograph from a given small experimental watershed. The linear reservoir model is a conceptual model, consisting of cascade or parallel equal linear reservoirs, preceded by a linear channel which involved Nash, SLR(single linear reservoir) and 2-PLR(two-parallel linear Reservoir) model. the Nash model have two parameters N and K, single linear reseroir has one parameter $K_I$ and two-parallel linear reservoirs have two parameters $K_1,\;K_2$; where N denote the number of reservoirs and K is the storage coefficient of each reservoirs.

  • PDF

선형 저수지 유형의 parameter 연구

  • 서영재;고재웅
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 1987년도 제29회 수공학연구발표회논문초록집
    • /
    • pp.151-158
    • /
    • 1987
  • The purpose of thes study is to estimate the parameters of linear reservoir models in order to derive the instantaneous unit hydrograph from a given small experimental watershed. The linear reservoir model is a conceptual model, consisting of cascade or parallel equal linear reservoirs, preceded by a linear channel which involved NASH, SLR(single linear reservoir)and 2-PLR(two-parallel linear reservoir)model. The NASH model have two parameters N and K, single linear reservoir has one parameter K1 and two-parallel linear reservoirs have two parameters K1, K2;where N denote the number of reservoirs and K is the storage coefficient of each reservoirs.

  • PDF

Noninformative priors for linear function of parameters in the lognormal distribution

  • Lee, Woo Dong;Kim, Dal Ho;Kang, Sang Gil
    • Journal of the Korean Data and Information Science Society
    • /
    • 제27권4호
    • /
    • pp.1091-1100
    • /
    • 2016
  • This paper considers the noninformative priors for the linear function of parameters in the lognormal distribution. The lognormal distribution is applied in the various areas, such as occupational health research, environmental science, monetary units, etc. The linear function of parameters in the lognormal distribution includes the expectation, median and mode of the lognormal distribution. Thus we derive the probability matching priors and the reference priors for the linear function of parameters. Then we reveal that the derived reference priors do not satisfy a first order matching criterion. Under the general priors including the derived noninformative priors, we check the proper condition of the posterior distribution. Some numerical study under the developed priors is performed and real examples are illustrated.

리니어 컴프레서를 위한 파라미터 추정 및 제어 (Parameter Identification and Control for Linear Compressors)

  • 김규식
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
    • /
    • pp.243-245
    • /
    • 2006
  • A closed-loop sensorless stroke control system for a linear compressor has been designed. The motor parameters are identified as a function of the piston position and the motor current. They are stored in ROM table and used later for the accurate estimation of piston position. Also it was attempted to approximate the identified motor parameters to the 2nd-order surface functions. Some experimental results are given in order to show the feasibility of the proposed control schemes for linear compressors.

  • PDF

방사선 투과 각도에 따른 족부 방사선 지표의 변화: Phantom Foot을 이용한 연구 (Change of Radiologic Index of Foot according to Radiation Projection Angle: A Study Using Phantom Foot)

  • 김어진;서상교;이동연
    • 대한족부족관절학회지
    • /
    • 제19권4호
    • /
    • pp.165-170
    • /
    • 2015
  • Purpose: The purpose of this study is to analyze the measurement differences of simple radiographs according to radiation projection angle using a phantom and to propose methods for objective analysis of simple radiographs. Materials and Methods: We took simple radiographs with different projection angles using a C-arm image intensifier and measured five parameters of the foot on the simple radiographic images. Five parameters include lateral tibiocalcaneal angle, lateral talocalcaneal angle, naviculocuboid overlap, lateral talo-first metatarsal angle, and lateral calcaneo-first metatarsal angle. Intraobserver and interobserver reliability were verified, and then intraclass correlations of parameters were analyzed. Results: Radiographic parameters of the foot showed high intraobserver and interobserver reliability. Lateral tibiocalcaneal angle has a strong negative linear relationship with rotation and a moderate negative linear relationship with tilt. Lateral talocalcaneal angle has a moderate positive linear relationship with rotation and a strong positive linear relationship with tilt. Naviculocuboid overlap has a strong positive linear relationship with rotation and a moderate positive linear relationship with tilt. Lateral talo-first metatarsal angle does not have a linear relationship with rotation and a moderate negative linear relationship with tilt. Lateral calcaneo-first metatarsal angle has a moderate positive linear relationship with rotation and tilt. Conclusion: More precise evaluation of the foot with a simple radiograph can be performed by understanding the changes of radiographic parameters according to radiation projection angle.

유역특성에 따른 탱크모형 매개변수의 변화 (An Evaluatiou of Parameter Variations for a Linear Reservoir (TANK) Model with Watershed Characteristics)

  • 김현영;박승우
    • 한국농공학회지
    • /
    • 제28권2호
    • /
    • pp.42-52
    • /
    • 1986
  • This study involves the estimation of optimal ranges of parameters for a linear watershed model. A well-known TANK model was chosen and a linear combination of four tanks assumed. The model was used to simulate daily streamflow for six watersheds of different sizes and by a trial-and-error approach a set of optimal parameters defined. The parameters were related to watershed sizes and land use conditions. Optimal parameters for ungaged conditions were defined from the relationships; daily streamflow simulated and compared to the observed date. The simulated results were in a general agreement with the data.

  • PDF

Nonlinear dynamic analysis of spiral stiffened cylindrical shells rested on elastic foundation

  • Foroutan, Kamran;Shaterzadeh, Alireza;Ahmadi, Habib
    • Steel and Composite Structures
    • /
    • 제32권4호
    • /
    • pp.509-519
    • /
    • 2019
  • In this paper, an analytical approach for the free vibration analysis of spiral stiffened functionally graded (SSFG) cylindrical shells is investigated. The SSFG shell is resting on linear and non-linear elastic foundation with damping force. The elastic foundation for the linear model is according to Winkler and Pasternak parameters and for the non-linear model, one cubic term is added. The material constitutive of the stiffeners is continuously changed through the thickness. Using the Galerkin method based on the von $K\acute{a}rm\acute{a}n$ equations and the smeared stiffeners technique, the non-linear vibration problem has been solved. The effects of different geometrical and material parameters on the free vibration response of SSFG cylindrical shells are adopted. The results show that the angles of stiffeners and elastic foundation parameters strongly effect on the natural frequencies of the SSFG cylindrical shell.

OPTIMAL RESTRICTIONS ON REGRESSION PARAMETERS FOR LINEAR MIXTURE MODEL

  • Park, Sung-Hyun;Ahn, Jung-Yeon
    • 한국품질경영학회:학술대회논문집
    • /
    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
    • /
    • pp.239-250
    • /
    • 1998
  • A method of finding optimal linear restriction on regression parameters in linear model for mixture experiments in the sense of minimizing integrated mean squared error is studied. We use the formulation of optimal restrictions on regression parameters for estimating responses proposed by Park(1981) by transforming mixture components to mathematically independent variables.

  • PDF

리니어 컴프레서의 제어성능 향상 (Control Performance Improvement for Linear Compressors)

  • 김규식
    • 전기학회논문지
    • /
    • 제56권3호
    • /
    • pp.594-599
    • /
    • 2007
  • A dosed-loop sensorless stroke control system for a linear compressor has been designed. The motor parameters are identified as a function of the piston position and the motor current. They are stored in ROM table and used later for the accurate estimation of piston position. Also it was attempted to approximate the identified motor parameters to the 2nd-order surface functions. The 2nd-order surface functions are divided into 2 or 4 sub-sections for more precise identification of motor parameters. Some experimental results are given in order to show the feasibility of the proposed control schemes for linear compressors.

Joint parameter identification of a cantilever beam using sub-structure synthesis and multi-linear regression

  • Ingole, Sanjay B.;Chatterjee, Animesh
    • Structural Engineering and Mechanics
    • /
    • 제45권4호
    • /
    • pp.423-437
    • /
    • 2013
  • Complex structures are usually assembled from several substructures with joints connecting them together. These joints have significant effects on the dynamic behavior of the assembled structure and must be accurately modeled. In structural analysis, these joints are often simplified by assuming ideal boundary conditions. However, the dynamic behavior predicted on the basis of the simplified model may have significant errors. This has prompted the researchers to include the effect of joint stiffness in the structural model and to estimate the stiffness parameters using inverse dynamics. In the present work, structural joints have been modeled as a pair of translational and rotational springs and frequency equation of the overall system has been developed using sub-structure synthesis. It is shown that using first few natural frequencies of the system, one can obtain a set of over-determined system of equations involving the unknown stiffness parameters. Method of multi-linear regression is then applied to obtain the best estimate of the unknown stiffness parameters. The estimation procedure has been developed for a two parameter joint stiffness matrix.