scholarly journals Comparative Analysis of Load Forecasting Models for Varying Time Horizons and Load Aggregation Levels

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7128
Author(s):  
Leonard Burg ◽  
Gonca Gürses-Tran ◽  
Reinhard Madlener ◽  
Antonello Monti
Keyword(s):  
Comparative Analysis ◽  
Prediction Models ◽  
Load Forecasting ◽  
Real Data ◽  
Computational Effort ◽  
Two Dimensions ◽  
Forecasting Models ◽  
Time Horizons ◽  
Selection Of

Power system operators are confronted with a multitude of new forecasting tasks to ensure a constant supply security despite the decreasing number of fully controllable energy producers. With this paper, we aim to facilitate the selection of suitable forecasting approaches for the load forecasting problem. First, we provide a classification of load forecasting cases in two dimensions: temporal and hierarchical. Then, we identify typical features and models for forecasting and compare their applicability in a structured manner depending on six previously defined cases. These models are compared against real data in terms of their computational effort and accuracy during development and testing. From this comparative analysis, we derive a generic guide for the selection of the best prediction models and features per case.

scholarly journals The Impact of the Selection of Exogenous Variables in the ANFIS Model on the Results of the Daily Load Forecast in the Power Company

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 345
Author(s):  
Janusz Sowinski
Keyword(s):  
Load Forecasting ◽  
Large Set ◽  
Exogenous Variables ◽  
Anfis Model ◽  
Load Forecast ◽  
Forecasting Models ◽  
Power Company ◽  
Ex Post ◽  
Daily Load ◽  
Selection Of

Forecasting of daily loads is crucial for the Distribution System Operators (DSO). Contemporary short-term load forecasting models (STLF) are very well recognized and described in numerous articles. One of such models is the Adaptive Neuro-Fuzzy Inference System (ANFIS), which requires a large set of historical data. A well-recognized issue both for the ANFIS and other daily load forecasting models is the selection of exogenous variables. This article attempts to verify the statement that an appropriate selection of exogenous variables of the ANFIS model affects the accuracy of the forecasts obtained ex post. This proposal seems to be a return to the roots of the Polish econometrics school and the use of the Hellwig method to select exogenous variables of the ANFIS model. In this context, it is also worth asking whether the use of the Hellwig method in conjunction with the ANFIS model makes it possible to investigate the significance of weather variables on the profile of the daily load in an energy company. The functioning of the ANFIS model was tested for some consumers exhibiting high load randomness located within the area under supervision of the examined power company. The load curves featuring seasonal variability and weekly similarity are suitable for forecasting with the ANFIS model. The Hellwig method has been used to select exogenous variables in the ANFIS model. The optimal set of variables has been determined on the basis of integral indicators of information capacity H. Including an additional variable, i.e., air temperature, has also been taken into consideration. Some results of ex post daily load forecast are presented.

Disease Classification Using ECG Signals Based on R-Peak Analysis With ABC and ANN

2019 ◽  
Vol 8 (2) ◽  
pp. 67-86 ◽  
Author(s):  
Suman Lata ◽  
Rakesh Kumar
Keyword(s):  
Feature Extraction ◽  
Comparative Analysis ◽  
Classification Accuracy ◽  
Disease Classification ◽  
Cardiac Diseases ◽  
Ecg Signals ◽  
Processing Steps ◽  
Ann Classification ◽  
Selection Of

ECG feature extraction has an important role in identifying a number of cardiac diseases. Lots of work has been done in this field but the most important challenges faced in previous work are the selection of proper R-peaks and R-R intervals due to the lack of appropriate pre-processing steps like decomposition, smoothing, filtering, etc., and the optimization of the features for proper classification. In this article, DWT-based pre-processing and ABC is used for optimization of features which helps to achieve better classification accuracy. It is utilized for initial diagnosis of abnormalities. The signals are taken from MIT-BIH arrhythmia database for the analysis. The aim of the research is to classification of six diseases; Normal, Atrial, Paced, PVC, LBBB, RBBB with an ABC optimization algorithm and an ANN classification algorithm on the basis of the extracted features. Various parameters, like, FAR, FRR, and accuracy are measured for the execution. Comparative analysis is shown of the proposed and the existing work to depict the effectiveness of the work.

scholarly journals Semantics and Ideography of Dostoevsky's Handwritten Text: from Handwriting to Meaning

2020 ◽  
Vol 7 (4) ◽  
pp. 222-291
Author(s):  
Nataliya Tarasova ◽  
Tatyana Panyukova
Keyword(s):  
Comparative Analysis ◽  
Scientific Work ◽  
Handwritten Text ◽  
Russian State ◽  
Art Collection ◽  
True Meaning ◽  
History Of ◽  
Storage Units ◽  
Selection Of

The paper analyzes the material from two workbooks (1864–1867) that belonged to Feodor Dostoevsky (Russian State Archive of Literature and Art. Collection 212, inventory 1, storage units 4 and 5). The research was conducted in three main areas: selection of information for the letter style alphabet; comparative analysis of sources (manuscripts and publications of handwritten text) for the purpose of identifying and correcting errors in its reading; a review of calligraphy and graphics of Feodor Dostoevsky. The alphabet of letter styles allows to establish typical and atypical letter styles in the handwriting of Feodor Dostoevsky. This made it possible to compile a classification of letters, describe their features, and use this information in the study of difficult-to-read and previously undecipherable records. The latter may contain valuable information that allows to clarify the facts in the creative history of the works of Feodor Dostoevsky, biographical information, chronology of the creative process, and so on. The second area of research includes the comparative analysis of manuscript sources and their published versions — is of particular value for ascertaining the original author's text and eliminating the inaccuracies of research interpretations that often appear in the process of manuscript publishing. There is a direct connection between these areas of analysis — the letter style alphabet is a tool that allows to read the handwritten text more accurately and correct the mistakes of the publishers. The third direction, dedicated to the study of calligraphy, expands the range of tasks related to the study of graphics in the writer's texts and allows to draw preliminary conclusions about the nature of its function in the handwritten text. The scientific novelty of the work consists in the systematization of data on the writer's handwriting in manuscripts of the specified period, on the features of his creative work, and in correcting the errors made by publishers of handwritten materials and restoring the true meaning of the author's notes. The practical value of the work consists in collecting information about the writer's handwriting, which is relevant for the textual analysis of his works, publication of his texts, and use of the collected information for subsequent scientific work.

scholarly journals Integration of Demand Response and Short-Term Forecasting for the Management of Prosumers’ Demand and Generation

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 11 ◽  
Author(s):  
María Carmen Ruiz-Abellón ◽  
Luis Alfredo Fernández-Jiménez ◽  
Antonio Guillamón ◽  
Alberto Falces ◽  
Ana García-Garre ◽  
...  
Keyword(s):  
Power Systems ◽  
Demand Response ◽  
Time Series Data ◽  
Load Forecasting ◽  
Real Data ◽  
Series Data ◽  
Renewable Generation ◽  
Short Term ◽  
Forecasting Models ◽  
Short Term Forecasting

The development of Short-Term Forecasting Techniques has a great importance for power system scheduling and managing. Therefore, many recent research papers have dealt with the proposal of new forecasting models searching for higher efficiency and accuracy. Several kinds of artificial intelligence (AI) techniques have provided good performance at predicting and their efficiency mainly depends on the characteristics of the time series data under study. Load forecasting has been widely studied in recent decades and models providing mean absolute percentage errors (MAPEs) below 5% have been proposed. On the other hand, short-term generation forecasting models for photovoltaic plants have been more recently developed and the MAPEs are in general still far from those achieved from load forecasting models. The aim of this paper is to propose a methodology that could help power systems or aggregators to make up for the lack of accuracy of the current forecasting methods when predicting renewable energy generation. The proposed methodology is carried out in three consecutive steps: (1) short-term forecasting of energy consumption and renewable generation; (2) classification of daily pattern for the renewable generation data using Dynamic Time Warping; (3) application of Demand Response strategies using Physically Based Load Models. Real data from a small town in Spain were used to illustrate the performance and efficiency of the proposed procedure.

scholarly journals Comparative analysis between prediction models in codes and test data for shear strength

2013 ◽  
Vol 6 (6) ◽  
pp. 875-902 ◽  
Author(s):  
F. P. Hirata ◽  
R. G. M. de Andrade ◽  
J. C. Della Bella
Keyword(s):  
Shear Strength ◽  
Reinforced Concrete ◽  
Comparative Analysis ◽  
Laboratory Tests ◽  
Prediction Models ◽  
Reinforcement Rate ◽  
Reinforced Concrete Beams ◽  
Shear Stresses ◽  
Academic Publications

Since the beginning of twentieth century, along with academic publications of Ritter and Mörsch, several studies have been done in order to understand shear strength in reinforced concrete elements. Approximately 1,200 laboratory tests results of reinforced concrete beams under shear stresses were used in a comparative analysis among values from prediction models of codes and laboratory tests results, enabling classification of the codes according to their applicability in several tests intervals. Although the Brazilian Code NBR 6118 (2007) showed good results in usual ranges of parameters, it presented unsatisfactory results on the following cases: low and medium shear transverse reinforcement rate.

Disease Classification Using ECG Signals Based on R-Peak Analysis With ABC and ANN

2022 ◽  
pp. 933-954
Author(s):  
Suman Lata ◽  
Rakesh Kumar
Keyword(s):  
Feature Extraction ◽  
Comparative Analysis ◽  
Classification Accuracy ◽  
Disease Classification ◽  
Cardiac Diseases ◽  
Ecg Signals ◽  
Processing Steps ◽  
Ann Classification ◽  
Selection Of

ECG feature extraction has an important role in identifying a number of cardiac diseases. Lots of work has been done in this field but the most important challenges faced in previous work are the selection of proper R-peaks and R-R intervals due to the lack of appropriate pre-processing steps like decomposition, smoothing, filtering, etc., and the optimization of the features for proper classification. In this article, DWT-based pre-processing and ABC is used for optimization of features which helps to achieve better classification accuracy. It is utilized for initial diagnosis of abnormalities. The signals are taken from MIT-BIH arrhythmia database for the analysis. The aim of the research is to classification of six diseases; Normal, Atrial, Paced, PVC, LBBB, RBBB with an ABC optimization algorithm and an ANN classification algorithm on the basis of the extracted features. Various parameters, like, FAR, FRR, and accuracy are measured for the execution. Comparative analysis is shown of the proposed and the existing work to depict the effectiveness of the work.

scholarly journals Chiller Load Forecasting Using Hyper-Gaussian Nets

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3479
Author(s):  
Manuel R. Arahal ◽  
Manuel G. Ortega ◽  
Manuel G. Satué
Keyword(s):  
Load Forecasting ◽  
Real Data ◽  
Local Models ◽  
Prediction Horizon ◽  
Expected Performance ◽  
Selection Of Variables ◽  
Auto Regressive ◽  
Forecasting System ◽  
Spatial Support ◽  
Selection Of

Energy load forecasting for optimization of chiller operation is a topic that has been receiving increasing attention in recent years. From an engineering perspective, the methodology for designing and deploying a forecasting system for chiller operation should take into account several issues regarding prediction horizon, available data, selection of variables, model selection and adaptation. In this paper these issues are parsed to develop a neural forecaster. The method combines previous ideas such as basis expansions and local models. In particular, hyper-gaussians are proposed to provide spatial support (in input space) to models that can use auto-regressive, exogenous and past errors as variables, constituting thus a particular case of NARMAX modelling. Tests using real data from different world locations are given showing the expected performance of the proposal with respect to the objectives and allowing a comparison with other approaches.

Use of photodynamic therapy for photodamage skin (review of literature)

2019 ◽  
Vol 1 (7) ◽  
pp. 19-23
Author(s):  
S. I. Surkichin ◽  
N. V. Gryazeva ◽  
L. S. Kholupova ◽  
N. V. Bochkova
Keyword(s):  
Photodynamic Therapy ◽  
Comparative Evaluation ◽  
Clinical Manifestations ◽  
Light Sources ◽  
Review Of Literature ◽  
Photosensitizing Agents ◽  
Selection Of

The article provides an overview of the use of photodynamic therapy for photodamage of the skin. The causes, pathogenesis and clinical manifestations of skin photodamage are considered. The definition, principle of action of photodynamic therapy, including the sources of light used, the classification of photosensitizers and their main characteristics are given. Analyzed studies that show the effectiveness and comparative evaluation in the selection of various light sources and photosensitizing agents for photodynamic therapy in patients with clinical manifestations of photodamage.

Philosophcal review of h. white̕s tropological theory in the context of the new philosophy of history

2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta
Keyword(s):  
Modern Science ◽  
Historical Knowledge ◽  
Text Organization ◽  
The Social ◽  
History Of ◽  
Actual Material ◽  
The Common ◽  
Historical Nature ◽  
Selection Of

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.

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