• 제목/요약/키워드: Residuals

검색결과 625건 처리시간 0.026초

On the Cointegrating Relationship between Stock Prices and Earnings

  • Nam, Doo-Woo
    • 산학경영연구
    • /
    • 제20권2호
    • /
    • pp.1-13
    • /
    • 2007
  • The purpose of this study is to investigate a simple present value model Involving earnings (i.e., the earnings discount model) that presumes a relationship between stock prices and earnings. The model suggests a simple linear equilibrium relationship between stock prices and earnings. The tests for cointegration render strong support for the cointegration hypothesis between stock prices (Pt) and earnings (Xt) even at the one-percent significance level. The tests are based on residuals from a cointegrating regression of Pt on Pt+l + Xt. This suggests that there is a stable long-nu equilibrium relationship between stock prices and earnings. The results of the tests lead to the acceptance of the present value model of stock prices involving earnings.

  • PDF

수치지도 좌표계 전환에 관한 연구 (Development of Coordinate Transformation Tool for Existing Digital Map)

  • 윤홍식;조재명;송동섭;김명호;조흥묵
    • 한국측량학회:학술대회논문집
    • /
    • 한국측량학회 2003년도 추계학술발표회 논문집
    • /
    • pp.373-378
    • /
    • 2003
  • This study deals with development of transformation tool for transformation of digital map coordinates systems using by the best fit transformation parameters which are determined between the local geodetic datum and geocentric datum (ITRF2000) in Korea and distortion modelling derived from collocation method. We used 107 control points as a common points. For analyzing the derived parameters, another 83 common points are tested. Finally, the best fit parameters are determined from Molodensky-Badekas model after considering the RMSE, maximum value, minimum values, and 95% confidence interval of residuals. after transformation of best fit parameters and distortion modelling, we could develop transformation tools with advenced accuracy. so it is possible to perform on transformation of digital map with scale 1:5,000. and we tested accuracy eveluation through analysis between transformation results and field results of GPS observation.

  • PDF

3 계 슬라이딩 모드 관측기 기반 로봇 고장 진단 (Third Order Sliding Mode Observer based Robust Fault Diagnosis for Robot Manipulators)

  • 반 미엔;강희준;서영수
    • 제어로봇시스템학회논문지
    • /
    • 제18권7호
    • /
    • pp.669-672
    • /
    • 2012
  • This paper investigates an algorithm for robust fault diagnosis in robot manipulators. The TOSM (Third Order Sliding Mode observer) provides both theoretically exact observation and unknown fault identification without filtration. The EOI (Equivalent Output Injections) of the TOSM observers can be used as residuals for the problem of fault diagnosis and to identify the unknown faults. The obtained fault information can be used for fault detection, isolation as well as fault accommodation to the self-correcting failure system. The computer simulation results for a PUMA 560 robot are shown to verify the effectiveness of the proposed strategy.

Nonlinear section model for analysis of RC circular tower structures weakened by openings

  • Lechman, Marek;Stachurski, Andrzej
    • Structural Engineering and Mechanics
    • /
    • 제20권2호
    • /
    • pp.161-172
    • /
    • 2005
  • This paper presents the section model for analysis of RC circular tower structures based on nonlinear material laws. The governing equations for normal strains due to the bending moment and the normal force are derived in the case when openings are located symmetrically in respect to the bending direction. In this approach the additional reinforcement at openings is also taken into account. The mathematical model is expressed in the form of a set of nonlinear equations which are solved by means of the minimization of the sums of the second powers of the residuals. For minimization the BFGS quasi-Newton and/or Hooke-Jeeves local minimizers suitably modified are applied to take into account the box constraints on variables. The model is verified on the set of data encountered in engineering practice. The numerical examples illustrate the effects of the loading eccentricity and size of the opening on the strains and stresses in concrete and steel in the cross-sections under consideration. Calculated results indicate that the additional reinforcement at the openings increases the resistance capacity of the section by several percent.

확장형 미지입력 관측기를 이용한 위성 반작용 휠의 고장 검출 (Fault Detection of a Spacecraft's Reaction Wheels by Extended Unknown Input Observer)

  • 진재현;용기력
    • 제어로봇시스템학회논문지
    • /
    • 제17권11호
    • /
    • pp.1138-1144
    • /
    • 2011
  • This article deals with the problem of fault detection of a spacecraft's actuators. The authors introduce an extended unknown input observer for nonlinear systems. This is an extended form of unknown input observers which are used for linear systems. Since faults are not available, those are considered as unknown inputs. Unknown input observers can estimate states without full information of inputs if some conditions are satisfied. The authors suggest a continuous-time extended UIO (eUIO) and prove the convergence of state estimation errors. Since the dynamic equation of a spacecraft is nonlinear, an extended UIO can be applied. Three eUIOs are designed to monitor three reaction wheels. The moving averages of each eUIO's residuals are selected for decision logic. The proposed method is verified by numerical simulations.

Nanoscale Fluoropolymer Pattern Fabrication by Capillary Force Lithography for Selective Deposition of Copper

  • 백장미;이린;성명모
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
    • /
    • pp.369-369
    • /
    • 2012
  • The present work deals with selective deposition of copper on fluoropolymers patterned silicon (111) surfaces. The pattern of fluoropolymer was fabricated by nanoimprint lithography (NIL) and plasma reactive ion etching (RIE) was used to remove the residuals layers. Copper was electrochemically deposited in bare Si regions which were not covered with fluoropolymers. The patterns of fluoropolymers and copper have been investigated by scanning electron microscopy (SEM). In this work, we used two deposition methods. One is galvanic displacement method and another is electrodeposition. Selective deposition works in both cases and it shows applicability to other materials. By optimization of the deposition conditions can be achieved therefore this process represents a simple approach for a direct high resolution patterning of silicon surfaces.

  • PDF

Effects of Error Path Delay on Stability of the Filtered-x/Constrained Filtered-x LMS Algorithm

  • Na, Hee-Seung
    • The Journal of the Acoustical Society of Korea
    • /
    • 제17권3E호
    • /
    • pp.43-46
    • /
    • 1998
  • Many of the active noise control system utilize a form of the least mean square(LMS) algorithm. This paper discusses the dependence of the convergence rate on the acoustic error path in the popular algorithm which is conventional "filtered-x LMS" and introduces new algorithm "constrained filtered-x LMS". The proposed method increase the convergence region regardless of the time-delay in the acoustic error path. In the algorithms, coefficients of the controller are adapted using the residuals of constrained structure which are defined in such a way that the control process become stationary. Advantages of constrained filtered-x LMS algorithm is illustrated by convergence analysis in the mean sense.

  • PDF

엔트로피 극대화 통행배분모형의 효율적 해법 개발 (Development of an Efficient Solution Method for the Wilson's Trip Distribution Model)

  • 노정현
    • 대한교통학회지
    • /
    • 제9권2호
    • /
    • pp.121-126
    • /
    • 1991
  • Wilson made an importent contribution to develop a trip distribution model with the general form of gravity model which is an entropy maximization program. Also Wilson suggested a technique which is called the "iterative balancing method" for soving the model. This te-chnique however is not stable to find solution because it is a heuristic method and sometimes does not converge to the correct solution. In this paper a new solution method using a numerical method for solving the non-linear simultaneous equation system is developed and evaluated in both computers VAX 8700 and PC/AT 286 The result of this method and Wilson's method are compared with each other. Wilson's method resulted in inferior solutions measured by the final norm of residuals.

  • PDF

A Comparision on CERES & Robust-CERES

  • 오광식;도수희;김대학
    • 한국데이터정보과학회:학술대회논문집
    • /
    • 한국데이터정보과학회 2003년도 추계학술대회
    • /
    • pp.93-100
    • /
    • 2003
  • It is necessary to check the curvature of selected covariates in regression diagnostics. There are various graphical methods using residual plots based on least squares fitting. The sensitivity of LS fitting to outliers can distort their residuals, making the identification of the unknown function difficult to impossible. In this paper, we compare combining conditional expectation and residual plots(CERES Plots) between least square fit and robust fits using Huber M-estimator. Robust CERES will be far less distorted than their LS counterparts in the presence of outliers and hence, will be more useful in identifying the unknown function.

  • PDF

Control of postharvest fungal spoilage of kiwifruit with TiO$_2$ photocatalytic ozonation.

  • Hur, Jae-Seoun;Oh, Soon-Ok;Kim, Minjin;Jung, Jae-Sung;Koh, Young-Jin
    • 한국식물병리학회:학술대회논문집
    • /
    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
    • /
    • pp.87.3-88
    • /
    • 2003
  • TiO$_2$photocatalytic ozonation was attempted to disinfect fungal pathogens causing postharvest spoilage of kiwifruits and to decompose fungicide residuals on kiwifruits. TiO$_2$Photocatalytic ozonation process synergistically degraded organic compound and inhibited conidial germination of the fungal pathogen compared to single treatment of ozonation or photocatalysis. The efficient control of fungal spoilage and degradation of residual fungicide on kiwifruits indicate that TiO$_2$photocatalytic ozonation is a very attractive method for postharvest disease control of kiwifruits as an alternative to fungicides application.

  • PDF