Interest in sports predictions as well as the public availability of large amounts of structured and unstructured data are increasing every day. As sporting events are not completely independent ...events, but characterized by the influence of the human factor, the adequate selection of the analysis process is very important. In this paper, seven different classification machine learning algorithms are used and validated with two validation methods: Train&Test and cross-validation. Validation methods were analyzed and critically reviewed. The obtained results are analyzed and compared. Analyzing the results of the used machine learning algorithms, the best average prediction results were obtained by using the nearest neighbors algorithm and the worst prediction results were obtained by using decision trees. The cross-validation method obtained better results than the Train&Test validation method. The prediction results of the Train&Test validation method by using disjoint datasets and up-to-date data were also compared. Better results were obtained by using up-to-date data. In addition, directions for future research are also explained.
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This paper proposes an approach to schedule and allocate regulating reserve in systems with a large share of generation from wind power plants (WPPs). The method for scheduling regulating power is ...based on the correction of day-ahead schedules planned by the known variations of the load- and wind-power from the previous hour. The correction term incorporates the tendency of changes for previous hours. In this way, more of the regulating power can be reserved during sudden changes in the intensity of the wind. Hence, available existing operational data are required, instead of historical data. The method for allocation of regulating power to regulating units is based on minimization of the transmission losses with optional correction according to economic criteria. The qualitative analysis of the relevant economic features is introduced, as well as the possibilities for applying advanced information and communications technology. The methods discussed were tested for the standard test network RTS 96 and for the Croatian transmission network. Test results showed considerable reduction of the unnecessary positive and negative regulating reserve with increased safety compared to the classic method. Furthermore, optimal allocation of regulating reserve reduced transmission losses for all the cases discussed. Reductions were more significant when the layouts of WPPs and regulating capacities were more geographically dispersed.
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Disruptions in the global market are influencing value and supply chains reminding businesses and industries that variability and diversity of supply chains may be essential for surviving and ...sustainability. Operations management of any business has to address these challenges in order to avoid any serious interruptions in supply of materials in production industries by seeking substitute inputs. At the same time, the technological development offers new materials with similar quality properties, making thereby the substitute material search more difficult in terms of selecting appropriate materials with a level of quality which is similar enough. Another aspect in shifting can be found in more social-related reasons addressing changes in the value chains like traceability, low carbonization, and a more customer-oriented approach, because of moving towards green digital business. In this sense the intention of this work was to propose an algorithm for customizing the process of identifying appropriate materials in production by relying on existing algorithms i.e., the Ashby mapping, big data, applying algorithms of data analysis based on exclusion criteria embracing transformation paradigms, for enabling customization of the material selection process. The proposed algorithm was applied on two case examples, demonstrating that diversity of materials plays an important role in addressing customization requests from customers. Consequently, understanding and implementing a customer-centric approach in various phases of the product life cycle contributes to a better response by businesses faced with issuing customized offerings.
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Many intentionally vulnerable web applications are circulating on the Internet that serve as a legal test ground for practicing SQL injection attacks. For demonstration purposes the attacks will ...target an Acunetix test web application created using PHP programming language and MySQL relational database. In the practical part, the execution of the attack itself largely depends on the database management system, so the displayed syntax is intended only for the MySQL database management system. Example of an automated attack will be executed on SQLmap in a Linux Kali virtualized environment. Security guidelines with a purpose of protecting databases are also discussed.
Monitoring, protection and control of the electrical power system require the design and implementation of specific applications that are based on analytical methods for the processing of ...synchronized measurements. Therefore, it is necessary to select the adequate type of mathematical analysis that best suits the requirements of a particular application. This paper describes analytical methods used for the processing of synchronized measured electrical quantities for detection and analysis of the variety of oscillations. The oscillatory phenomena of active power and frequency as a case study of one disturbance in the power system are analyzed. The results of processing the actual synchronized measurements for that case study are presented afterwards. Different data processing methods (spectral analysis methods) are compared, and finally, a recommendation for appropriate methods for processing synchronized measurements in application for recognition, processing and alarming of oscillations of active power is given.
This paper analyses how the type of winding affects the current distribution and power losses in armature winding. Using finite element method, four different types of winding used in large ...asynchronous motors are analyzed: form-wound concentric, with and without transposition, and form-wound barrel, with and without transposition, for the stationary state. In two cases, the calculation shows clear differences between maximum currents in strands, a shift in their phases, and a resulting increase of AC resistance. In two other cases, minor deviations, smaller phase shift and smaller increase of AC resistance, are detected. It indicates that in certain types of armature winding of large motors the strands transposition leads to significant positive effects in terms of motor power, while in other cases it leads to unnecessary complications making the manufacture of large asynchronous machines more difficult, with relatively small positive effect on the motor power losses.
The System Integrity Protection Scheme (SIPS) is a specialized protection scheme which differs to a great extent from the common protection, especially in its main intention. It is designed for ...integrity protection, failure prevention and mitigation of disturbance consequences in the whole power system (PS) or modern distribution system (MDS) with a significant power of distributed generation (DG). The input parameters for establishing SIPS in PS are synchronized phasor measurements obtained from the Phasor Measurement Units (PMUs), as a globally acknowledged Smart Grid technology. The realization requires that SIPS is added to the existing Wide Area Monitoring, Protection and Control (WAMPAC), based on synchronized measurements. This paper proposes an algorithm that anticipates optimal PMU placement and then uses angular stability protection based on traditional iEDs supported by synchronized measurements. By using such approach, the system avoids possible blackouts due to the combined operation of the traditional protection and WAMPAC. The proposed SIPS system is tested on specific area in the Croatian transmission system integrating hydro power and wind energy converting power plants. Due to the increased power of renewable energy sources (RES), the proposed algorithm is applicable to modern distribution systems.
Analyses of alternating electrical circuits in electrical engineering are usually based on assumption that currents and voltages are sinusoidal values. Such assumption allows analysis of electrical ...networks by symbolic mathematical calculation. It also allows the application of vector diagrams in representing relationship of the analyzed electrical values. In practice, periodic non sinusoidal values are sometimes found. For solving such values symbolic mathematical calculation and vector diagrams cannot be used. In this paper is shown how such non sinusoidal periodic values can be separated, by applying Fourier series, into infinite series which contains a constant term and infinitely many harmonic components. That way allows all the acquired knowledge and methods for solving sinusoidal periodic values to still be used.Original Abstract: Analize izmjenicnih strujnih krugova u elektrotehnici su najcesce bazirane na pretpostavci da su struje i naponi sinusoidalne velicine. Takva pretpostavka omogucuje analizu elektricnih mreza simbolickim matematickim racunom te primjenu vektorskih dijagrama u prikazivanju odnosa analiziranih elektricnih velicina. U praksi se ponekad susrecu periodicke nesinusoidalne velicine za cije rjesavanje se ne mogu koristiti simbolicki matematicki racun i vektorski dijagrami. U ovom je radu prikazano kako se takve nesinusoidalne periodicke velicine mogu primjenom Fourierovog reda rastaviti na beskonacni red koji sadrzi konstantan clan i beskonacno mnogo harmonickih komponenata. Na taj nacin omoguceno je da se sva usvojena znanja i metode rjesavanja sinusoidalnih periodickih velicina mogu i dalje koristiti.
The development and usage of ICT technologies are increasing every day. Nowadays, ICT technologies are being used in almost every industry and lately, especially rapidly in sports. Information ...related to sports events and sports participants are recorded in a database, which thus enables computer analysis. This paper presents an information system Basketball Coach Assistant. The paper presents a current version of the information system and describes the possibilities of the information system, starting with the architecture up to the individual parts of the
information system. The paper also explains a display of a custom menu and user-defined player efficiency index.
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