6,424 research outputs found

    Data-based mechanistic modelling, forecasting, and control.

    Get PDF
    This article briefly reviews the main aspects of the generic data based mechanistic (DBM) approach to modeling stochastic dynamic systems and shown how it is being applied to the analysis, forecasting, and control of environmental and agricultural systems. The advantages of this inductive approach to modeling lie in its wide range of applicability. It can be used to model linear, nonstationary, and nonlinear stochastic systems, and its exploitation of recursive estimation means that the modeling results are useful for both online and offline applications. To demonstrate the practical utility of the various methodological tools that underpin the DBM approach, the article also outlines several typical, practical examples in the area of environmental and agricultural systems analysis, where DBM models have formed the basis for simulation model reduction, control system design, and forecastin

    European exchange trading funds trading with locally weighted support vector regression

    Get PDF
    In this paper, two different Locally Weighted Support Vector Regression (wSVR) algorithms are generated and applied to the task of forecasting and trading five European Exchange Traded Funds. The trading application covers the recent European Monetary Union debt crisis. The performance of the proposed models is benchmarked against traditional Support Vector Regression (SVR) models. The Radial Basis Function, the Wavelet and the Mahalanobis kernel are explored and tested as SVR kernels. Finally, a novel statistical SVR input selection procedure is introduced based on a principal component analysis and the Hansen, Lunde, and Nason (2011) model confidence test. The results demonstrate the superiority of the wSVR models over the traditional SVRs and of the v-SVR over the Δ-SVR algorithms. We note that the performance of all models varies and considerably deteriorates in the peak of the debt crisis. In terms of the kernels, our results do not confirm the belief that the Radial Basis Function is the optimum choice for financial series

    Is it time to withdraw from china?

    Get PDF
    This research cross-employs the Social Cognitive Theory (SCT) and three major labor theories comprised of Maslow’s theory, Alderfer’s theory and Herzberg’s theory with Multiple Criteria Decision Making (MCDM) consisting of Factor Analysis (FA), Analytical Network Process (“ANP”), Fuzzy Analytical Network Process (FANP) and Grey Relation Analysis (GRA) to evaluate the four types of innovative investment strategies in China after the Domino Effect of the China’s Labor Revolution. The most contributed conclusion is that the “change of original business at the raising compensation policy” (CBRCP) is the best choice for Taiwanese manufacturers operating in China because it is the highest scores of three assessed measurements in the CBRCP. This conclusion further indicates that manufacturing enterprises have little leverage, in the interim, but to increase employment compensation and benefits to satisfy the demands from the ongoing Chinese labor revolution even though it brings about an incremental expenditure in their manufacturing costs. Therefore, the next step beyond this research is to collect additional empirical macroeconomic data to develop a more comprehensive evaluation model that takes into consideration a more in-depth vertical measurement and horizontal assessment methodologies for developing added comprehensive and effective managerial strategies for surviving in this momentous, dynamically-changing and lower-profit Chinese manufacturing market.China labor revolution; Maslow theory; Alderfer theory and Herzberg theory; Multiple criteria decision making

    Wind Power Forecasting Methods Based on Deep Learning: A Survey

    Get PDF
    Accurate wind power forecasting in wind farm can effectively reduce the enormous impact on grid operation safety when high permeability intermittent power supply is connected to the power grid. Aiming to provide reference strategies for relevant researchers as well as practical applications, this paper attempts to provide the literature investigation and methods analysis of deep learning, enforcement learning and transfer learning in wind speed and wind power forecasting modeling. Usually, wind speed and wind power forecasting around a wind farm requires the calculation of the next moment of the definite state, which is usually achieved based on the state of the atmosphere that encompasses nearby atmospheric pressure, temperature, roughness, and obstacles. As an effective method of high-dimensional feature extraction, deep neural network can theoretically deal with arbitrary nonlinear transformation through proper structural design, such as adding noise to outputs, evolutionary learning used to optimize hidden layer weights, optimize the objective function so as to save information that can improve the output accuracy while filter out the irrelevant or less affected information for forecasting. The establishment of high-precision wind speed and wind power forecasting models is always a challenge due to the randomness, instantaneity and seasonal characteristics

    A novel Big Data analytics and intelligent technique to predict driver's intent

    Get PDF
    Modern age offers a great potential for automatically predicting the driver's intent through the increasing miniaturization of computing technologies, rapid advancements in communication technologies and continuous connectivity of heterogeneous smart objects. Inside the cabin and engine of modern cars, dedicated computer systems need to possess the ability to exploit the wealth of information generated by heterogeneous data sources with different contextual and conceptual representations. Processing and utilizing this diverse and voluminous data, involves many challenges concerning the design of the computational technique used to perform this task. In this paper, we investigate the various data sources available in the car and the surrounding environment, which can be utilized as inputs in order to predict driver's intent and behavior. As part of investigating these potential data sources, we conducted experiments on e-calendars for a large number of employees, and have reviewed a number of available geo referencing systems. Through the results of a statistical analysis and by computing location recognition accuracy results, we explored in detail the potential utilization of calendar location data to detect the driver's intentions. In order to exploit the numerous diverse data inputs available in modern vehicles, we investigate the suitability of different Computational Intelligence (CI) techniques, and propose a novel fuzzy computational modelling methodology. Finally, we outline the impact of applying advanced CI and Big Data analytics techniques in modern vehicles on the driver and society in general, and discuss ethical and legal issues arising from the deployment of intelligent self-learning cars

    Conditioning the Estimating Ultimate Recovery of Shale Wells to Reservoir and Completion Parameters

    Get PDF
    In the last years, gas production from shale has increased significantly in the United States. Therefore, many studies have been focused on shale formation in different areas such as fracturing, reservoir simulation, forecasting and so on. Forecasting production or estimating ultimate recovery (EUR) is considered to be one of the most important items in the production development planning. The certainty in EUR calculation is questionable because there are different parameters that impact production and consequently the EUR such as rock properties and well completion design.;Different methods to calculate EUR have been used in the industry. Traditionally, the decline curve analysis method by Arps (1945) was considered to be the best common tool for estimating ultimate recovery (EUR) and reserves. However, the Arps\u27 equations over estimate of reserves when they are applied to unconventional reservoirs (extremely low permeability formation). The reason is that Arps\u27 equations only work for Boundary Dominated Flow (BDF) decline. On the other hand, many research papers show that the production from the unconventional tight reservoirs is distinguished by an extended period of late transient flow, until reaching the boundary-dominated flow. To overcome these problems and improve the unconventional reservoir\u27s production forecast, researchers have developed new empirical methods which are being implemented in all flow regimes.;These new and traditional methods have been applied in this research to calculate the EUR for more than 200 shale wells. The results of EUR will be subjected to study and condition with rock properties, well characteristics and completion\u27s design parameters. The porosity, total organic carbon, net thickness and water saturation are the main rock properties that are considered in this research. Furthermore, the impact of different well design configurations (for instance, well trajectories, completion and hydraulic fracturing variable) on EUR will be inspected this study. In addition, it will be determined from this research whether reservoir or completion parameters have the most impact on EUR. This study will provide the natural gas professionals insight and clarification regarding the effects of rock properties and well design configurations on estimating the ultimate recovery for gas shale

    Activity-aware HVAC power demand forecasting

    Get PDF
    The forecasting of the thermal power demand is essential to support the development of advanced strategies for the management of local resources on the consumer side, such as heating ventilation and air conditioning (HVAC) equipment in buildings. In this paper, a novel hybrid methodology is presented for the short-term load forecasting of HVAC thermal power demand in smart buildings based on a data-driven approach. The methodology implements an estimation of the building's activity in order to improve the dynamics responsiveness and context awareness of the demand prediction system, thus improving its accuracy by taking into account the usage pattern of the building. A dedicated activity prediction model supported by a recurrent neural network is built considering this specific indicator, which is then integrated with a power demand model built with an adaptive neuro-fuzzy inference system. Since the power demand is not directly available, an estimation method is proposed, which permits the indirect monitoring of the aggregated power consumption of the terminal units. The presented methodology is validated experimentally in terms of accuracy and performance using real data from a research building, showing that the accuracy of the power prediction can be improved when using a specialized modeling structure to estimate the building's activity.Peer ReviewedPostprint (author's final draft

    Using fuzzy cognitive maps in modelling and representing weather lore for seasonal weather forecasting over east and Southern Africa

    Get PDF
    Published ArticleThe creation of scientific weather forecasts is troubled by many technological challenges while their utilization is dismal. Consequently, the majority of small-scale farmers in Africa continue to consult weather lore to reach various cropping decisions. Weather lore is a body of informal folklore associated with the prediction of the weather based on indigenous knowledge and human observation of the environment. As such, it tends to be more holistic and more localized to the farmers’ context. However, weather lore has limitations such as inability to offer forecasts beyond a season. Different types of weather lore exist and utilize almost all available human senses (feel, smell, sight and hear). Out of all the types of weather lore in existence, it is the visual or observed weather lore that is mostly used by indigenous societies to come up with weather predictions. Further, meteorologists continue to treat weather lore knowledge as superstition partly because there is no means to scientifically evaluate and validate it. The visualization and characterization of visual sky objects (such as moon, clouds, stars, rainbow, etc) in forecasting weather is a significant subject of research. In order to realize the integration of visual weather lore knowledge in modern weather forecasting systems, there is a need to represent and scientifically substantiate weather lore. This article is aimed at coming up with a method of organizing the weather lore from the visual perspective of humans. To achieve this objective, we used fuzzy cognitive mapping to model and represent causal relationships between weather lore concepts and weather outcomes. The results demonstrated that FCMs are efficient for matrix representation of selected weather outcome scenarios caused visual weather lore concepts. Based on these results the recommendation of this study is to use this approach as a preliminary processing task towards verifying weather lore
    • 

    corecore