• 제목/요약/키워드: Modelling and evaluation

검색결과 272건 처리시간 0.031초

객체지향 시스템 모델링 차원 : 이론 및 탐색적 평가 (A Study on the Dimensions of Object-oriented Systems Modeling : Theory and an Exploratory Evaluation)

  • 안준모
    • 정보기술과데이타베이스저널
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    • 제8권1호
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    • pp.41-65
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    • 2001
  • This study proposes evaluation dimensions of object-oriented systems modelling tools and activities available in object-oriented systems development practices. The dimensions ale developed based on previous research in cognitive psychology, information systems modeling study, and object-oriented systems analysis arid design areas. The proposed dimension is composed of two dimensions. The one dimension includes abstraction levels of modelling and the other includes process and representation in modeling activities. Experts on object-oriented modeling were selected to evaluate the practical validity of the proposed dimensions and applications of major object-oriented modeling tools during systems development project. Most of the tools were observed to be used for representing objects rather than for modeling the process of related objects. The proposed modeling dimension will be evaluated for acquiring general validity in future empirical research.

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Study of nonlinear hysteretic modelling and performance evaluation for piezoelectric actuators based on activation functions

  • Xingyang Xie;Yuguo Cui;Yang Yu
    • Smart Structures and Systems
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    • 제33권2호
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    • pp.133-143
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    • 2024
  • Piezoelectric (PZT) actuators have been widely used in precision positioning fields for their excellent displacement resolution. However, due to the inherent characteristics of piezoelectric actuators, hysteresis has been proven to greatly reduce positioning performance. In this paper, five mathematical hysteretic models based on activation function are proposed to characterize the nonlinear hysteresis characteristics of piezoelectric actuators. Then the performance of the proposed models is verified by particle swarm optimization (PSO) algorithm and the experiment data. Thirdly, the fitting performance of the proposed models is compared with the classical Bouc-Wen model. Finally, the performance of the five proposed models in modelling hysteresis nonlinearity of piezoelectric drivers is compared, in terms of RMSE, MAPE, SAPE and operation efficiency, and relevant suggestions are given.

라그랑지안 입자추적법에 의한 유출유 확산모델링 (The Application of Lagrangian Particle-Tracking Method to Modelling of Oil-Spill Dispersion)

  • 정연철
    • 해양환경안전학회지
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    • 제3권1호
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    • pp.73-83
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    • 1997
  • To predict the oil-spill dispersion in marine waters, the oil-spill dispersion model based on Lagrangian particle-tracking method was developed and applied to Kwangyang and Jinju Bay. The tidal current movements to be required as input data of the oil-spill dispersion model were obtained by a two-dimensional numerical tidal model. Evaluation of tidal current movements using mean tide was successful. Modelling results were compared with the field data obtained at spill site. There were some descrepancies between modeling results and field data. However, the general pattern of modelling results was similar to that of field data. Provided the real-time tidal currents and more accurate wind data are supported, more favorable results can be obtained.

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Modelling Growth and Yield for Intensively Managed Forests

  • Burkhart, Harold E.
    • Journal of Forest and Environmental Science
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    • 제24권3호
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    • pp.119-126
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    • 2008
  • Growth and yield prediction methods, ranging from whole-stand models to individual-tree models, have been developed for forest types managed for wood production. The resultant models are used for a host of purposes including inventory updating, management planning, evaluation of silvicultural alternatives, and harvest scheduling. Because of the large investment in developing growth and yield models for improved genotypes and silvicultural practices for loblolly pine (Pinus taeda) in the Southern United States, this region serves to illustrate approaches for modelling intensively managed forests. Analytical methods and computing power generally do not restrict development of reliable growth and yield models. However, long-term empirical observations on stand development, which are time consuming and expensive to obtain, often limit modelling efforts. Given that growth and yield models are used to project present volumes and to evaluate alternative treatment effects, data of both the inventory type and the experimental type are needed. Data for developing stand simulators for loblolly pine plantations have been obtained from a combination of permanent plots in operational forest stands and silvicultural experiments; these data collection efforts are described and summarized. Modelling is essential for integrating and synthesizing diverse information, identifying knowledge gaps, and making informed decisions. The questions being posed today are more complex than in the past, thus further accentuating the need for comprehensive models for stand development.

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기록치 오차와 유역모형의 검정(II) - 모니터링 검정방법 - (Errors in Recorded Information and Calibration of a Catchment Modelling System(II) - Monitoring Calibration Approach -)

  • Choi, Kyung Sook
    • 한국농공학회지
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    • 제45권5호
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    • pp.117-125
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    • 2003
  • Since the recorded information used for operation of a catchment modelling system contain errors that influence the calibration of catchment modelling system control parameter values, the accurate estimation of these parameters is difficult. Despite these influences, existing traditional calibration approaches focus only on achieving the best "curve fitting" between simulated and recorded data, and not on generic evaluation of control parameter values. This paper introduces an Early Stopping Technique which is aimed at avoiding the procedure of curve-fitting through monitoring improvements in the objective function used for assessing the optimal parameter set. Application of this approach to the calibration of SWMM (Storm Water Management Model) on the Centennial Park catchment in Sydney, Australia is outlined. outlined.

원음장 재생을 위한 OSS 등화기의 모델링에 관한 컴퓨터시뮬레이션 (Computer Simulation on the Modelling of OSS Equalizer for the Reproduction of Original Sound Field)

  • 임정빈;김천덕
    • 한국항해학회지
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    • 제16권4호
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    • pp.55-63
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    • 1992
  • This computer simulation is the basic research for realize a real-time hardware of the reproduction system in original sound field with two loudspeakers based on the OSS(Ortho Stereophonic System) method which was proposed by Hamada of Japan in 1983. Through the computer simulation, presumed the system function of OSS equalizer using HRTF(Head Related Transfer Function), constructed the model of OSS equalizer and , evaluated the modelling OSS equalizer by evaluation formula. The obtained results are summarized as follows : 1) By the modelling OSS equalize operate as inverse filter of HRTF, an input signal reproduced effectively. 2) Known that the real-time hardware of OSS equalizer can be made by the fast convolution between the impulse response of OSS equalizer and input speech signal. 3) Since the system function of OSS equalizer presumed from HRTF, the study on the measuring of HRTF have to proceed.

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초음파 이미지를 이용한 CFRP 복합적층판의 적층결함 평가 (On Evaluation of Stacking Fault in CERP Composite Plates of Using Ultrasonic Images)

  • 임광희;나승우;심재기;양인영
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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    • pp.121-124
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    • 2003
  • This paper shows shear wave behavior of CFRP(carton fiber reinforced plastics) composite laminates as a polar grid form to evaluate vibration pattern of ultrasonic transducers, which gives measured modelling fundamental contents of nondestructive evaluation. This modelling decomposes the transmission of a linearly polarized wave into orthogonal components through each ply of a laminate. It is found that a high probability shows between the model and measurement system in characterizing lay up of CFRP composite laminates. Also evaluating quantitatively the defects in CFRP laminates who found to be possible of normalized frequency obtained from 2D-FFT technique based on C-scan method. Thus, the technique is proven to be one of the useful means to evaluate any internal defect in CFRP composite laminates.

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제품사용성 평가를 위한 인체모델의 개발

  • 강동석;정의승
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.797-806
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    • 1995
  • An ergonomic evaluation model which can properly evaluate the design of a product or workplaces was developed to evaluate a new product in the early stage of design. Although several evaluation models have been developed and are in use in the field of ergonomics, they lack an integrated framework and analysis techniques. In this research, an ergonomic evaluation model was developed according to the framework which accommodates desirable components of the model. The framework represents the integration of four components: man model, workplace modeller, ergonomic evaluation functions and knowledge bases, which interact with a common object-oriented database. Components were developed individually and integrated with the workplace modeller. The generation and manipulation of man models, workplace modelling, and ergonomic evaluation features such as reach and visibility were implemented. The developed evaluation model has demonstrated distinct advantages of the flexibility to adapt another features for the ergonomic evaluation model and the better usability for users.

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AI-Enabled Business Models and Innovations: A Systematic Literature Review

  • Taoer Yang;Aqsa;Rafaqat Kazmi;Karthik Rajashekaran
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권6호
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    • pp.1518-1539
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    • 2024
  • Artificial intelligence-enabled business models aim to improve decision-making, operational efficiency, innovation, and productivity. The presented systematic literature review is conducted to highlight elucidating the utilization of artificial intelligence (AI) methods and techniques within AI-enabled businesses, the significance and functions of AI-enabled organizational models and frameworks, and the design parameters employed in academic research studies within the AI-enabled business domain. We reviewed 39 empirical studies that were published between 2010 and 2023. The studies that were chosen are classified based on the artificial intelligence business technique, empirical research design, and SLR search protocol criteria. According to the findings, machine learning and artificial intelligence were reported as popular methods used for business process modelling in 19% of the studies. Healthcare was the most experimented business domain used for empirical evaluation in 28% of the primary research. The most common reason for using artificial intelligence in businesses was to improve business intelligence. 51% of main studies claimed to have been carried out as experiments. 53% of the research followed experimental guidelines and were repeatable. For the design of business process modelling, eighteen AI mythology were discovered, as well as seven types of AI modelling goals and principles for organisations. For AI-enabled business models, safety, security, and privacy are key concerns in society. The growth of AI is influencing novel forms of business.