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This paper described research to investigate Total Harmonic Distortion (THD) on a supposedly green building; Admission Building in Universitas Muhammadiyah Yogyakarta. Observation was done for seven days involving peak and non-peak hours including workdays and off days. Data sampling was recorded 24 hours with one-hour interval for primary parameter data including voltage, current, power factor and frequency on each phase in three phases system. Secondary data calculated to find voltage and current THD and finally to evaluate the loss of money due to power loss as the result of harmonic and unbalance load. Investigation indicated that the building has not met the IEEE 512-2014 standard for Total Harmonic Distortion. National electricity company, PLN (Perusahaan Listrik Negara) as Government Company, has made regulation about tariff and standard. Electricity tariff in Indonesia has been divided into categories based on user, commercial, social, or housing. Based on this tariff, loss of cost was calculated. Cost due to electricity loss in the building was not high since the building has good electricity installation as green building. Total Harmonic distortion reduction was recommended using single tune order 5 filter.

In this study, the external load resistance of a magnetically coupled two-degree-of-freedom bistable energy harvester (2-DOF MCBEH) was optimized to maximize the harvested power output, considering the third-harmonic distortion in forced response. First, the nonlinear dynamic analysis was performed to investigate the characteristics of the large-amplitude interwell motions of the 2-DOF MCBEH. From the analysis results, it was found that the third-harmonic distortion occurs in the interwell motion of the 2-DOF MCBEH system due to the nonlinear magnetic coupling between the beams. Thus, in this study, the third-harmonic distortion was considered in the optimization process of the external load resistance of the 2-DOF MCBEH, which is different from the process of conventional impedance matching techniques suitable for linear systems. The optimal load resistances were estimated for harmonic and swept-sine excitations by using the proposed method, and all the results of the power outputs were in excellent agreements with the numerically optimized results. Furthermore, the associated power outputs were compared with the power outputs obtained by using the conventional impedance matching technique. The results of the power outputs are discussed in terms of the improvement in energy harvesting performance. ; Published version ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIT) (No. NRF-2019R1C1C1009732). This work was also supported by the BK21+ Program of the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education (MOE).

An analytical model has been developed for calculating magnetic field in a multiphase synchronous electric machine with fractional toothed windings. For this, a harmonic analysis of the distribution functions of the magnetic field of excitation and the magnetic field of the armature reaction was carried out, taking into account the presence of higher harmonic components in the function of the magnetomotive force of permanent magnets, variable magnetic conductivity of the air gap, polyharmonic mode of operation of a multiphase electric machine and a non-sinusoidal law of variation of spatial winding functions. As a result of the analysis, the substantiation is given that in the investigated electric machine a nine-phase winding can extract with the greatest efficiency the harmonic components of the first and third order of a rotating magnetic field to create flux linkage and induce an electromotive force (as well as create a magnetomotive force with prevailing spatial harmonics of the first and third order). In the investigated electric machine, the amplitudes of the working harmonics of the induction of the modulated magnetic field of the armature reaction can be increased due to the modulation of the inoperative harmonics of the magnetomotive force of the armature response by the stator teeth to the first and third order. To check the developed provisions, a magnetostatic vector model of the magnetic field of the investigated electric machine was created. The simulation results confirmed the high efficiency of the developed analytical model for calculating the magnetic field in a synchronous electric machine with fractional toothed windings. The use of such a model will make it possible to reveal most reliably the influence of the geometricparameters of the magnetic circuit and the multiphase winding circuit on the nature of the change in the functions of the magnetic field in the air gap with the lowest time costs in the process of optimizing an electric machine.

Summary: Seasonality in suicide rates has long been reported. Spring peaks in suicide deaths have been positively correlated with the proportion of the workforce engaged in agriculture. Some studies have indicated that suicides using violent methods are more likely to show seasonality. Recent research has suggested that seasonal patterns have diminished. This study examined deaths in male farmers, an occupational group which might be expected to be more vulnerable to seasonal influences because of the nature of their work and the relatively high proportion of farmers using violent methods for suicide. Data on suicides between 1982 and 1999 by males in England and Wales aged 15 years and over were provided by the Office for National Statistics. Seasonal patterns of suicide in farmers and nonfarmers were examined by nonparametric tests and harmonic analysis. No significant seasonal variation was found for farmers. For nonfarmers, although a chi-square test showed significant variation in monthly distribution, this was not found when a harmonic analysis was applied. There was no significant difference in the variation of violent suicides throughout the year. This study reinforces recent findings that seasonal variation in suicide appears to be diminishing, even in an occupational group where this might be expected.

In the last two decades there is very sharp rise in the power generation from the solar system. This is due to the increasing solar cell efficiency, decreasing PV system costs, increasing government support, and many other factors collectively help in reduce the barriers of growth for PV systems to expand their participation to the total world energy sector. The drawbacks of the inverters which are currently used in grid connected PV system are well known. As the penetration of PV system is increasing day by day this problem is becoming more significant. This paper provide a solution in the control of inverter by regulating the active power and reactive power. The proposed control scheme helps in providing grid support by PV system as well as reducing the harmonics contents in the power hence improving power quality. The design, modeling, and analysis of a grid tied PV system was performed in the MATLAB software simulation environment. Results indicate that in the presence of grid disturbances the proposed inverter can react dynamically to help restore the power system back to its normal state. A harmonic analysis was also performed indicating the inverter under study met the applicable power quality standards for distributed energy resources. Javeed Ahmad Khan "Modelling and Analysis of Grid Connected PV System under Different Penetration Level of PV" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: https://www.ijtsrd.com/papers/ijtsrd12952.pdf

This work presents a stability analysis of microwave power amplifiers (PAs) driven by binary pulse trains, as in the case of class-S PAs. First, using a simplified digital PA test bench in class-D configuration, different qualitative behaviors are obtained when varying the pulsewidth, including subharmonic and incommensurable oscillations. The mechanisms affecting the stability properties are studied with a harmonic balance-based formulation, by means of pole-zero identification and bifurcation detection. A sufficiently high number of harmonic components must be considered, together with the Krylov decomposition for an efficient computation of the inverse of the Jacobian matrix. It is demonstrated that, when varying the pulsewidth, the distinct pairs of complex-conjugate poles may shift to the right-hand side of the complex plane and, therefore, lead to different kinds of unstable behavior. This phenomenon is related to the dependence of the critical poles on the average value of the input signal. Boundaries of the various types of unstable behavior are traced in the plane defined by the pulse repetition rate and pulsewidth, using bifurcation detection techniques. All the predicted phenomena have been confirmed experimentally. In a second step, the algorithms derived from the simple class-D circuit are transferred to study the stability of a more complex tri-band class-S amplifier. It has been analyzed versus the input bitrate, obtaining a fully stable behavior that has been validated experimentally. ; This work has been supported by the Spanish Government under contract TEC2014-60283-C3-1-R, the European Regional Development Fund (ERDF/FEDER) and the Parliament of Cantabria (12.JP02.64069).

The disadvantage of the geometry of thin-walled parts, in terms of processing, is the low ability to resist static and dynamic loads. It is caused by the elastic deformation of elements with a low stiffness. Modelling approaches for the evaluation of deflections during machining are presented. Mathematical models of deflections, cutting forces and harmonic response are proposed. The processes of material removal and deflection of a thin-walled sample at the critical points are modelled. A frequency analysis was performed, consisting of a modal analysis of natural frequencies and a harmonic response analysis. As a result, a graph of the deflections amplitude from the frequency of driven harmonic oscillations is generated. The analysis of the obtained values was performed. As a result, the resonance frequency and maximum amplitude of oscillations for the operating parameters are determined.

Correlations of two flow harmonics vn and vm via three-and four-particle cumulants are measured in 13 TeV pp, 5.02 TeV p+Pb, and 2.76 TeV peripheral Pb+Pb collisions with the ATLAS detector at the LHC. The goal is to understand the multi-particle nature of the long-range collective phenomenon in these collision systems. The large non-flow background from dijet production present in the standard cumulant method is suppressed using a method of subevent cumulants involving two, three and four subevents separated in pseudorapidity. The results show a negative correlation between v2 and v3 and a positive correlation between v2 and v4 for all collision systems and over the full multiplicity range. However, the magnitudes of the correlations are found to depend on the event multiplicity, the choice of transverse momentum range and collision system. The relative correlation strength, obtained by normalisation of the cumulants with the (v2n) from a two-particle correlation analysis, is similar in the three collision systems and depends weakly on the event multiplicity and transverse momentum. These results based on the subevent methods provide strong evidence of a similar long-range multi-particle collectivity in pp, p+Pb and peripheral Pb+Pb collisions. ; We acknowledge the support of ANPCyT, Argentina; YerPhI, Ar-menia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azer-baijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF and Benoziyo Center, Is-rael; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portu-gal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Feder-ation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slove-nia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individ-ual groups and members have received support from BCKDF, the Canada Council, CANARIE, CRC, Compute Canada, FQRNT, and the Ontario Innovation Trust, Canada; EPLANET, ERC, ERDF, FP7, Hori-zon 2020 and Marie Skłodowska-Curie Actions, European Union; Investissements d'Avenir Labex and Idex, ANR, Région Auvergne and Fondation Partager le Savoir, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF; BSF, GIF and Minerva, Israel; BRF, Norway; CERCA Programme Generalitat de Catalunya, Generalitat Valenciana, Spain; the Royal Society and Leverhulme Trust, United Kingdom.

Electric motor systems are the largest consumers of industrial electrical energy. As Variable Speed Drives continue to dominate various industrial processes, there is need for stakeholders to fully understand and quantify the converter-fed motor losses over a wide range of operating conditions. Such knowledge is crucial for both manufacturers and end-users in performing energy-efficiency optimizations for motor-drive applications. Although there is an increase in legislative activities, particularly in Europe, toward classification and improvement of energy efficiency of electric motor-drive systems, the available standards for quantifying the various losses are still in their early stages of development. None of these standards have yet passed through all the required phases for them to be considered full international standards, owing to a lack of consensus on many technical issues. Therefore, the need for researchers to provide feedback to the relevant standards committees cannot be over-emphasized. One of the most challenging issues in estimating the efficiency of converter-fed motors is the accurate determination of additional harmonic losses due to the PWM voltages and currents. Although the recently introduced IEC 60034-2-3 Technical Specification has proposed a method of determining these losses through experimental testing, the approach is still undergoing validation. Moreover, it only considers the rated motor frequency and voltage whereas induction motor drives are usually operated over a wide range of speed and torque. The main emphasis of the work presented in this dissertation was to develop a thorough understanding of various converter-fed induction motor losses, and hence efficiency, when fed from a 2-level Voltage Source Inverter. In particular, the dissertation provides a healthy questioning of some concepts in the proposed IEC method, with a view to providing useful feedback for improving the standard. Comparisons are also drawn between the related standards to identify areas for improvement. This study further attempts to explain some conflicting reports cited in literature regarding the nature of additional harmonic losses. The experimental results obtained by testing three induction motors demonstrate some of the technical issues associated with the determination of additional harmonic losses. To mitigate the adverse effect of varying technical skill and competence levels on efficiency test results, an automated testing procedure was developed and implemented on the 110kW test rig in the UCT Machines Lab. The test rig, which boasts of a Genesis 7i high-speed Data Acquisition System, also provides an energy-efficient platform for investigating the steadystate and dynamic characteristics of converter-fed motors. By utilizing the capability of the Data Acquisition System to segregate the fundamental and harmonic components of measured input electrical power, it was found that a PWM power supply can be used in place of a conventional Variac to estimate the sinusoidal supply efficiency of an induction motor. This is a welcome development for both laboratory and field efficiency testing applications.

The article discusses the problem of cyclicality of the price index of goods and services (CPI), recognizing that it is worthwhile to conduct research to better understand this phenomenon, since the behavior of prices is crucial to the functioning of the economy. To determine the cyclical nature of the CPI the author uses harmonic analysis, which allowed him to determine the strength and length variations in this ratio. The study covers the period of 2003–2012. The CPI calculated "month to the same month of the previous year" shows fairly stronger periodic fluctuations than the calculated "month to previous month".

In a motor vehicle, the term power train describes the main components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive (drive wheels, continuous track as in military tanks or caterpillar tractors, propeller, etc.). Sometimes "power train" is used to refer to simply the engine and transmission, including the other components only if they are integral to the transmission. This project aim is to explain how components function and then represent their behavior through mathematical models based on the physics of their operation. Then, the components can be combined together as a complete power train system and the resulting model should provide an important tool to contribute to vehicle design. The design process was done in SOLIDWORKS 2015 and it includes parts such as flywheel, clutch and gearbox. Assembly model was imported into ANSYS WORKBENCH 14.5 to analyze on structural parts. It includes static, model and harmonic analyses are performed on power train. Then we concluded that which material is suitable for the design of Power train depends on the analysis results.

In this paper, a new technique is presented for the analysis of the transient dynamics of microwave oscillators. The technique makes use of a nonlinear admittance function that can be identified in commercial Harmonic Balance software. This function is included in a time-frequency domain equation governing the transient dynamics. The equation provides the growth rate function of the first harmonic amplitude, which allows an exhaustive analysis of the transient speed from the neighborhood of the dc solution to the oscillation establishment, with no need for a numerical integration, as in time domain or envelope-transient methods. The technique has been applied to predict the length of the transient towards the oscillating state of a FET oscillator at 5 GHz. ; This work has been supported by the Spanish Ministry of Economy and Competitiveness under project TEC2014-60283-C3-1-R and the Parliament of Cantabria (12.JP02.64069). The authors would like to thank S. Pana, University of Cantabria, for her assistance with the manufacturing process.

The study aims to determine the competitiveness of Türkiye's UAV exports in a dynamic framework. The analysis used data from the first 20 countries with the largest share in the production and trade of products designated as UAVs by the Harmonic System six-digit and by the European Commission for 2012-2021. Within the scope of the study, it is determined that some countries have high competitiveness in 4 product groups examined with five different foreign trade indexes. It is concluded that Türkiye has strategic and dynamic superiority in two of the four product groups.