• 제목/요약/키워드: single variable

검색결과 1,306건 처리시간 0.039초

가변형 단일 궤도를 이용한 장애물 극복방법에 관한 연구 (Study of a Variable Single-tracked Crawler for Overcoming Obstacles)

  • 김지홍;이창구
    • 제어로봇시스템학회논문지
    • /
    • 제16권4호
    • /
    • pp.391-395
    • /
    • 2010
  • In our paper, we propose an asymmetric single-tracked wheel system, and describe its structure and the method for maintaining the length of a transformable track system. And the method is reducing the gap of lengths. Therefore, we propose an efficient structure for transforming and explain motions with kinematics. Our transformable shape single-tracked mobile system has an advantage to overcome an obstacle or stairs by the variable arms in the single unity track system. But we will make the variable shape of tracked system get a drive that has a force to stand against a wall. In this case, we can consider this system to a rigid body and have a notice that this single tracked system is able to get vary shape with the variable arm angle. Considering forces balance along x-axis and y-axis, and moments balance around the center of the mass we have. If this rigid body is standing against a wall and doesn't put in motion, the force of flat ground and the rigid body sets an equal by a friction. In the same way, the force of a wall and the rigid sets an equal by a friction.

Efficient estimation and variable selection for partially linear single-index-coefficient regression models

  • Kim, Young-Ju
    • Communications for Statistical Applications and Methods
    • /
    • 제26권1호
    • /
    • pp.69-78
    • /
    • 2019
  • A structured model with both single-index and varying coefficients is a powerful tool in modeling high dimensional data. It has been widely used because the single-index can overcome the curse of dimensionality and varying coefficients can allow nonlinear interaction effects in the model. For high dimensional index vectors, variable selection becomes an important question in the model building process. In this paper, we propose an efficient estimation and a variable selection method based on a smoothing spline approach in a partially linear single-index-coefficient regression model. We also propose an efficient algorithm for simultaneously estimating the coefficient functions in a data-adaptive lower-dimensional approximation space and selecting significant variables in the index with the adaptive LASSO penalty. The empirical performance of the proposed method is illustrated with simulated and real data examples.

Single-Phase Self-Excited Induction Generator with Static VAR Compensator Voltage Regulation for Simple and Low Cost Stand-Alone Renewable Energy Utilizations Part I : Analytical Study

  • Ahmed, Tarek;Noro, Osamu;Soshin, Koji;Sato, Shinji;Hiraki, Eiji;Nakaoka, Mutsuo
    • KIEE International Transactions on Power Engineering
    • /
    • 제3A권1호
    • /
    • pp.17-26
    • /
    • 2003
  • In this paper, the comparative steady-state operating performance analysis algorithms of the stand-alone single-phase self-excited induction generator (SEIG) is presented on the basis of the two nodal admittance approaches using the per-unit frequency in addition to a new state variable de-fined by the per-unit slip frequency. The main significant features of the proposed operating circuit analysis with the per-unit slip frequency as a state variable are that the fast effective solution could be achieved with the simple mathematical computation effort. The operating performance results in the simulation of the single-phase SEIG evaluated by using the per-unit slip frequency state variable are compared with those obtained by using the per-unit frequency state variable. The comparative operating performance results provide the close agreements between two steady-state analysis performance algorithms based on the electro-mechanical equivalent circuit of the single-phase SEIG. In addition to these, the single-phase static VAR compensator; SVC composed of the thyristor controlled reactor; TCR in parallel with the fixed excitation capacitor; FC and the thyristor switched capacitor; TSC is ap-plied to regulate the generated terminal voltage of the single-phase SEIG loaded by a variable inductive passive load. The fixed gain PI controller is employed to adjust the equivalent variable excitation capacitor capacitance of the single-phase SVC.

Variable Step Size Maximum Power Point Tracker Using a Single Variable for Stand-alone Battery Storage PV Systems

  • Ahmed, Emad M.;Shoyama, Masahito
    • Journal of Power Electronics
    • /
    • 제11권2호
    • /
    • pp.218-227
    • /
    • 2011
  • The subject of variable step size maximum power point tracking (MPPT) algorithms has been addressed in the literature. However, most of the addressed algorithms tune the variable step size according to two variables: the photovoltaic (PV) array voltage ($V_{PV}$) and the PV array current ($I_{PV}$). Therefore, both the PV array current and voltage have to be measured. Recently, maximum power point trackers that arc based on a single variable ($I_{PV}$ or $V_{PV}$) have received a great deal of attention due to their simplicity and ease of implementation, when compared to other tracking techniques. In this paper, two methods have been proposed to design a variable step size MPPT algorithm using only a single current sensor for stand-alone battery storage PV systems. These methods utilize only the relationship between the PV array measured current and the converter duty cycle (D) to automatically adapt the step change in the duty cycle to reach the maximum power point (MPP) of the PV array. Detailed analyses and flowcharts of the proposed methods are included. Moreover, a comparison has been made between the proposed methods to investigate their performance in the transient and steady states. Finally, experimental results with field programmable gate arrays (FPGAs) are presented to verify the performance of the proposed methods.

단일변수 변환 행렬을 이용한 GRM 상수 생성 방법 (The method to produce GRM coefficient using single transform matrix)

  • 이철우;김영건
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 추계종합학술대회 논문집
    • /
    • pp.807-810
    • /
    • 1998
  • This paper propose the method to produce GRM(Generalized Reed-Muller)expansion. The general method to obtain GRM expansion coefficient for p valued n variable is derivation of single variable transform matrix and expand it n times using Kronecker product. In this case the size of matrix increases depending on the augmentation of variables. In this paper we propose the simple algorithm to produce GRM coefficient using a single variable transform matrix.

  • PDF

수정된 재생사이클 가스터빈의 설계 및 부분부하 성능해석 (Analysis of Design and Part Load Performance of a Modified Regenerative Cycle Gas Turbine)

  • 황성훈;김동섭
    • 유체기계공업학회:학술대회논문집
    • /
    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
    • /
    • pp.467-472
    • /
    • 2005
  • Characteristics of a Modified regenerative cycle gas turbine has been investigated. In the cycle, the turbine expansion is divided into two parts and the regenerator locates between them. Two types of mechanical design are assumed: two-shaft and single-shaft. In particular, optimal pressure ratio division between the high and low pressure turbines is evaluated for the single shaft configuration. The part load analyses have been carried out with the aid of off-design models. In addition to the general fuel only control, a variable speed control is assumed as the part load operating strategy of the single shaft configuration. Obvious advantage with the alternative cycle is observed in the variable speed operation of the single shaft design.

  • PDF

단상 영구자석 동기전동기의 속도 가변형 비례공진 전류제어에 관한 연구 (A Study on Speed Variable Proportional Resonant Current Controller of Single-Phase PMSM)

  • 이원석;황선환;박종원
    • 전기전자학회논문지
    • /
    • 제24권4호
    • /
    • pp.954-960
    • /
    • 2020
  • 본 논문은 단상 영구자석 동기전동기의 속도 가변형 비례공진 전류제어 기법을 제안한다. 단상 영구자석 동기전동기는 전자기적 특성상 고정자 전류와 역기전력의 위상차에 따른 부토크 및 영토크가 발생하며 센서리스 운전 시 낮은 고정자 저항과 인덕턴스로 인해 과전류 제한이 필요하다. 이러한 조건하에서 전류제어를 위해 3상 교류 전동기에 사용되는 벡터 제어를 이용할 경우, 좌표변환, 역좌표변환 및 가상의 dq축 성분을 생성하는 과정이 필요하다. 하지만, 단상 영구자석 동기전동기의 자기적 특성을 고려하여 제안한 속도 가변형 비례공진 전류제어 기법은 3상 교류 전동기에 사용되는 좌표변환 과정이 필요하지 않다. 본 논문에서는 가변 비례공진 전류제어 기법을 이용하여 안정적인 기동 성능을 확인하며 일정 속도 도달 시 위치 센서 없이 단상 영구자석 동기전동기의 수학적 모델 기반 센서리스 제어로 제안한 전류제어 기법의 효용성을 다수의 실험을 통해 검증하였다.

OC 곡선에 기초한 규준형 샘플링 검사 규격 (Revised KS Standards for Acceptance Sampling By Attribute and By Variable Based On OC Curve)

  • 최성운
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2008년도 추계학술대회
    • /
    • pp.505-515
    • /
    • 2008
  • This paper introduces six single and sequential acceptance sampling plans based on OC( Operating Characteristic) curve. Revised KS standards for acceptance sampling by attribute and by variable such as KSA 3102 : 1996, 3103 : 2005, KSA ISO 14560 : 2006, 8422 : 2001, 8423 : 2001 are presented.

  • PDF

전환규칙을 적용한 조정형 샘플링 검사의 종류 (Revised KS Standards for Acceptance Sampling By Attribute and By Variable Based On Switching Rule)

  • 최성운
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2008년도 추계학술대회
    • /
    • pp.517-526
    • /
    • 2008
  • This paper introduces fourteen single, double, multiple and sequential acceptance sampling plans based on switching rule. Revised KS standards for acceptance sampling by attribute and by variable such as KSA ISO 2859-0, 1:2001 2859-2:2001, 8422:2001, 3951:2006, 8423:2001, MIL-STD-105E:1989, 414:1968 and ANSI/ASQ Z1.4, Z1.9:2003 are presented.

  • PDF

상태변수피이드백에 의한 선형다변수제어시스템의 분할식설계에 관한 연구 (The Decoupling And Design Of Linear Multivariable Control Systems By State Variable Feedback)

  • 황창선
    • 전기의세계
    • /
    • 제23권2호
    • /
    • pp.46-54
    • /
    • 1974
  • The purposes of this paper are to deal with the design of m-input, m-output linear systems by the state variable feedback, and to extend the design capability of the state variable feedback design. The design requirements are decoupling and the exact realigation of desired transfer functions. Some methods are proposed to insert series compensators in the fixed plant in the cases when series compensators are needed to meet the input-output transfer matrix specification. The method for adding series compensators to the input channels of the fixed plant is shown by examples to lead both to the loss of the ability to decouple the augmented plant by the state variable feedback, and to the loss of desired zeroes. A method which avoids these two hazards is developed in which series compensators are put on the output channels of the fixed plant: it is proved that the augmented plant is F-invariant. By treating each subsystem individually, the designer can apply some of the previous developed knowledge of the state variable design of single-input, single-output systems.

  • PDF