Review of Different Error Metrics: A Case of Solar Forecasting

Renewable energy systems (RES) are no longer confined to being used as a stand-alone entity in the modern era. These RES, especially solar panels are also used with the grid power systems to supply electricity. However, precise forecasting of solar irradiance is necessary to ensure that the grid operates in a balanced and planned manner. Various solar forecasting models (SFM) are presented in the literature to produce an accurate solar forecast. Nevertheless, each model has gone through the step of evaluation of its accuracy using some error measures. Many error measures are discussed in the literature for deterministic as well as probabilistic solar forecasting. But, each study has its own selected error measure which sometimes landed on a wrong interpretation of results if not selected appropriately. As a result, this paper offers a critical assessment of several common error metrics with the goal of discussing alternative error metrics and establishing a viable set of error metrics for deterministic and probabilistic solar forecasting. Based on highly cited research from the last three years (2019-2021), error measures for both types of forecasting are presented with their basic functionalities, advantages & limitations which equipped the reader to pick the required compatible metrics

Fault Classification System for Switchgear CBM from an Ultrasound Analysis Technique Using Extreme Learning Machine

Currently, the existing condition-based maintenance (CBM) diagnostic test practices for ultrasound require the tester to interpret test results manually. Different testers may give different opinions or interpretations of the detected ultrasound. It leads to wrong interpretation due to depending on tester experience. Furthermore, there is no commercially available product to standardize the interpretation of the ultrasound data. Therefore, the objective is the correct interpretation of an ultrasound, which is one of the CBM methods for medium switchgears, by using an artificial neural network (ANN), to give more accurate results when assessing their condition. Information and test results from various switchgears were gathered in order to develop the classification and severity of the corona, surface discharge, and arcing inside of the switchgear. The ultrasound data were segregated based on their defects found during maintenance. In total, 314 cases of normal, 160 cases of the corona, 149 cases of tracking, and 203 cases of arcing were collected. Noise from ultrasound data was removed before uploading it as a training process to the ANN engine, which used the extreme learning machine (ELM) model. The developed AI-based switchgear faults classification system was designed and incorporated with the feature of scalability and can be tested and replicated for other switchgear conditions. A customized graphical user interface (GUI), Ultrasound Analyzer System (UAS), was also developed, to enable users to obtain the switchgear condition or classification output via a graphical interface screen. Hence, accurate decision-making based on this analysis can be made to prioritize the urgency for the remedial works.

La distribución tradicional del agua del río Turia entre las acequias de la Huerta de Valencia: Un sistema de origen bajomedieval

The water of the Turia river has been traditionally distributed in the Huerta of Valencia among eight irrigation canals through a system of 138 filas, a measure of water capacity which nature is not clear. It is also unknown what is the historical origin of this system of water division and this is what we study in this article. Thomas F. Glick defended that it was a system of Andalusi origin, and proposed a reconstruction of the original system based on time shifts, but we try to demonstrate that this proposal cannot be correct, especially because it is based on a wrong interpretation of the nature of the row. Subsequently, we provide an alternative proposal on the origin of the distribution system in 138 filas that is based on the proportionality between the amount of water that each irrigation canal has and the amount of land irrigated by each hydraulic system, concluding that the distribution system of the Huerta de Valencia can only have been established shortly after the Christian conquest of the thirteenth century, when the Huerta was greatly expanded and rebuilt. Finally, we conclude that this is another evidence of the great changes that took place in irrigated cultivation spaces of Andalusi origin after the Christian conquests, contrary to what had been said so far.

The Tafsīr Bi Al-Ma’ṡūr and Bi Al-Ra’yī in The Commentary of Abū Ja’far Al- Ṭaḥāwī

This study aims to investigate the tafsīr bi al-ma’ṡūr and bi al-ra’yī in the commentary of Abū Ja’far al-Ṭaḥāwī and its application methods. This study employed analytical descriptive method by employing content analysis theory towards the commentary of Aḥkām Al-Qur’ān Al-Karīm. The results suggest that Al-Ṭaḥāwī incorporates the tafsīr bi al-ma’ṡūr and bi al-ra’yī in his commentary although the general style is still the tafsīr bi al-ma’ṡūr. Al- Ṭaḥāwī has his own method in implementing the tafsīr bi al-ma’ṡūr and bi al-ra’yī. Among his methods in tafsīr bi al-ma’ṡūr is to compromise amongst narrations if it is possible, select and scientifically criticize the narrations, no comment, and avoid rejected Isrāiliyyāt narrations and false hadiṡ, unlike the commentary of al-Ṭabari. It is possible due to the differences of character between these two commentaries. Meanwhile, his method in tafsīr bi al-ra’yī is to reconcile both reasons and narrations in balance and equally important, avoid reasons outside their domain, interpret mutasyābihāt with muḥkamāt, and avoid wrong interpretation. Therefore, al-Ṭaḥāwī’s commentaries have been based on correct principles.

Turning points in agriculture development in Ukraine: results of analysis on the base of purified data

Purpose. The purpose of the paper is to study agriculture development in independent Ukraine using methods for decomposition of data sets to obtain structural components according to their level of determination and to investigate main tendencies without random fluctuation. Methodology / approach. This research uses econometrics methods of regression and correlation dynamics, data filtering from random factors impact, comparison method to reconstruct trends in agriculture development. The accent is made on the differences between results of analysis on the base of uncleaned and purified data. The cleaning process was made by the Hodrick-Prescott method for data sets decomposition without loss of information into several functions that describe behavior of system formed under deterministic, periodical, and stochastic influence. The calculations and their visualization were held by means of GNU Octave. The research covered the period of 1996–2018 years in development of agriculture, forestry, and fisheries in Ukraine. Results. This paper emphasizes on the necessity to clean data before its analysis. Unlike the analysis based on the raw data the reconstruction of relationships between filtered data sets allows building models of agriculture dynamics more precisely. The article presents reconstructed main correlated dynamics that were formed by deterministic impacts in Ukraine agriculture. Besides, the crucial turning points in Ukraine agriculture development were revealed because of analysis of filtered data. It is shown how data cleaning raises analysis quality. Originality / scientific novelty. Reconstruction of economy regression models on the dynamic data sets can be followed by the risks of wrong interpretation of results. To have correct explanation of regularity it matters to eliminate from data sets the fluctuations formed by random impacts and to study relation of tendencies in connection with structural shifts in the development of the country. The advisability and the necessity to use such approaches are proved by this research that was held on the base of statistical data from World Bank official site. It is the first reconstruction of the long-term agriculture dynamics of Ukraine on the base of filtered correlated data sets of 1996–2018. The main advantages of this research are the revealed turning points in Ukraine agriculture development that can be used by other researchers in investigation of economy and economic history. Practical value / implications. To raise precision of analysis and avoid wrong interpretation of outcomes it should be taken into consideration all factors that impact on events and thus it is rational to verify data and clean them from random oscillations especially studying long-term tendencies in the development of such systems as economy branches or country entire. Moreover, it helps to reveal peaks of growth and recession points in business activity and make more coherent predictions on the future development. The article presented the effectiveness of filter methods applying and results of analysis that can be used in management and forecast of long-term development in Ukraine agriculture. Such methodic can be applied to the analysis of both individual industries and the economy as a whole.

Punctuation Relevance in Subtitle: The Foreign Audience Example

This study looked at punctuation mark and their relevance in written information although; the objective of the study is to discover the relevance of punctuation mark in subtitle: The Foreign audience example and to re-echo the need to have a well punctuated write-up in literary genres. The study sees language as a system of human communication. The problem of the study sets in from lots of poor and wrongly applied punctuations, as various forms of signs are seen to be used in some of the movies of the entertainment industry – Nollywood, which in turn, gives rise to wrong interpretation to the foreign audience of that language, and as such, the foreign learner of a particular language, the Igbo example will not enjoy the supposed information. The study adopted the framework of Vinay and Darbelnet principles and strategies as a guide to solving the problem as one of its principles – equivalence was used to relate the movie wrong punctuated subtitles to their supposed target language. The methodology of explication is equally adopted while the study concludes that punctuation errors are involved with wrong application of punctuation mark to written discourses on where it is not supposed to be since punctuation occurs only in written discourses and not spoken.

Application of CISG in Arbitration: A Combined Procedure or Parallel Procedure?

CISG and arbitration are connected with each other. They may work through a combined or parallel procedure. Globalization of trade desires uniformity in trade. For uniformity of trade, we require uniform law. The arbitration may not work to make it uniform, but choosing any uniform law (i.e. CISG), it may lead to deal a particular arbitration in the international standard. The international standard may be maintained while considering the uniform law. Choosing uniform law (i.e. CISG), it may minimize the risk of wrong interpretation and put the arbitral parties on “equal footing”. Parties may consider CISG as the applicable law in their arbitral agreements. As of 13 February 2021, 94 states signed the United Nations Convention on Contracts for the International Sale of Goods 1980 (CISG). The frontline trading states like the USA, Australia, Israel, Canada, China, Germany, France, Russia, and Japan are contracting states of CISG. This research emphasizes providing guidelines as to how parties may apply CISG into their arbitral agreements by maintaining the international standard.

Estimation and correction of instrument artefacts in dynamic impedance spectra

Dynamic impedance spectroscopy is one of the most powerful techniques in the qualitative and quantitative mechanistic studies of electrochemical systems, as it allows for time-resolved investigation and dissection of various physicochemical processes occurring at different time scales. However, due to high-frequency artefacts connected to the non-ideal behaviour of the instrumental setup, dynamic impedance spectra can lead to wrong interpretation and/or extraction of wrong kinetic parameters. These artefacts arise from the non-ideal behaviour of the voltage and current amplifier (I/E converters) and stray capacitance. In this paper, a method for the estimation and correction of high-frequency artefacts arising from non-ideal behaviour of instrumental setup will be discussed. Using resistors, $$[\hbox {Fe(CN)}_6]^{3-/4-}$$ [ Fe(CN) 6 ] 3 - / 4 - redox couple and nickel hexacyanoferrate nanoparticles, the effect of high-frequency artefacts will be investigated and the extraction of the impedance of the system from the measured dynamic impedance is proposed. It is shown that the correction allows acquiring proper dynamic impedance spectra at frequencies higher than the bandwidth of the potentiostat, and simultaneously acquire high precision cyclic voltammetry.