Comparison of different optimization criteria for optimal sizing of hybrid active power filters parameters

Praise Worthy Prize granted a permission for Brunel University London to archive this article in BURA.Harmonic distortion in power systems has increased considerably due to the increasing use of nonlinear loads in industrial firms and elsewhere. This distortion can give rise to overheating in all sectors of the power system, leading to reduced efficiency, reliability, operational life and sometimes failure. This article seeks to propose a new methodology for the optimal sizing of hybrid active power filter (HPF) parameters in order to overcome the difficulties in hybrid power filters design when estimating the preliminary feasible values of the parameters. Sequential Quadratic Programming based on FORTRAN subroutines is used to find out the planned filter size in two different optimization criteria depending on design concerns. The first criterion is to minimize the total voltage harmonic distortion. The second one is to maximize the load power factor, while taking into account compliance with IEEE standard 519-1992 limits for the total voltage harmonic distortion and the power factor.The effectiveness of the proposed filter is discussed using four exemplary case

Hydraulic Analysis and Modelling Work of Tai Hang Tung Storage Scheme and its Associated Drainage System: final report, December 2010

Assessment OF Performance of Completed Drainage Works Against Designed Performance for Tai Hang Tung Storage Scheme (THTSS): final reportResearch & Development Report; no. RD 1052published_or_final_versio

A Canonical Author: The Case of Hesiod

This chapter presents a case study of the Lexicon’s treatment of a single author, Hesiod. Early Greek poetry in general, and that of Hesiod in particular, presents certain difficulties for the historical approach which do not arise for texts of later periods. The main body of the chapter is divided into three sections, treating different respects in which Liddell and Scott (LSJ), and the historical principle it adopts, may seem problematic for the modern reader of Hesiod. The first section considers the ways in which LSJ conflicts with current beliefs concerning the text and dating of Hesiod. The second outlines some respects in which the historical principle may be inadequate for dealing with early Greek hexameter in general, given more recent scholarship on the nature and semantics of formulaic verse. The third treats more idiosyncratic features of Hesiod’s poetry that are particularly noteworthy for the lexicographer. Throughout, the main focus is on the Theogony and the Works and Days

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Exciting Challenges - Rewarding Careers

Thank you for your interest in joining KTM Solutions. Here at KTM, we stand out among engineering companies as something new, fresh, and innovative. In a similar way, we seek to provide an experience for our employees that breaks the typical industry mold. Throughout my career as a mechanical engineer, I’ve greatly enjoyed a number of the assignments I’ve worked on. One of my most fulfilling assignments was the BRAVE 3000 program at the Boeing Military Airplane Company in Wichita, Kansas. Working on this project meant creativity, experimentation, and innovation. I was fortunate enough to work with a team of engineers who were considered the best in their class. We worked together, contributing to something bigger than our individual work. Our group had unparalleled support and encouragement from the top of the organization. It was exciting to work with a team and know that we were truly accomplishing something. It is my sincerest desire that each employee at KTM will encounter the same excitement, teamwork, and appreciation that I’ve had the privilege of experiencing. At KTM, you will find the satisfaction of working with a team of dedicated individuals who are respected and appreciated for the value they bring both to our company and to our clients. KTM Solutions is a place where each employee embarks on exciting challenges, experiences accomplishment through teamwork, and knows the satisfaction of succeeding together

Antiferromagnetic CuMnAs multi-level memory cell with microelectronic compatibility

Antiferromagnets offer a unique combination of properties including the radiation and magnetic field hardness, the absence of stray magnetic fields, and the spin-dynamics frequency scale in terahertz. Recent experiments have demonstrated that relativistic spin-orbit torques can provide the means for an efficient electric control of antiferromagnetic moments. Here we show that elementary-shape memory cells fabricated from a single-layer antiferromagnet CuMnAs deposited on a III–V or Si substrate have deterministic multi-level switching characteristics. They allow for counting and recording thousands of input pulses and responding to pulses of lengths downscaled to hundreds of picoseconds. To demonstrate the compatibility with common microelectronic circuitry, we implemented the antiferromagnetic bit cell in a standard printed circuit board managed and powered at ambient conditions by a computer via a USB interface. Our results open a path towards specialized embedded memory-logic applications and ultra-fast components based on antiferromagnets

Phase-rectified signal averaging method to predict perinatal outcome in infants with very preterm fetal growth restriction- a secondary analysis of TRUFFLE-trial

BACKGROUND: Phase-rectified signal averaging, an innovative signal processing technique, can be used to investigate quasi-periodic oscillations in noisy, nonstationary signals that are obtained from fetal heart rate. Phase-rectified signal averaging is currently the best method to predict survival after myocardial infarction in adult cardiology. Application of this method to fetal medicine has established significantly better identification than with short-term variation by computerized cardiotocography of growth-restricted fetuses. OBJECTIVE: The aim of this study was to determine the longitudinal progression of phase-rectified signal averaging indices in severely growth-restricted human fetuses and the prognostic accuracy of the technique in relation to perinatal and neurologic outcome. STUDY DESIGN: Raw data from cardiotocography monitoring of 279 human fetuses were obtained from 8 centers that took part in the multicenter European “TRUFFLE” trial on optimal timing of delivery in fetal growth restriction. Average acceleration and deceleration capacities were calculated by phase-rectified signal averaging to establish progression from 5 days to 1 day before delivery and were compared with short-term variation progression. The receiver operating characteristic curves of average acceleration and deceleration capacities and short-term variation were calculated and compared between techniques for short- and intermediate-term outcome. RESULTS: Average acceleration and deceleration capacities and short-term variation showed a progressive decrease in their diagnostic indices of fetal health from the first examination 5 days before delivery to 1 day before delivery. However, this decrease was significant 3 days before delivery for average acceleration and deceleration capacities, but 2 days before delivery for short-term variation. Compared with analysis of changes in short-term variation, analysis of (delta) average acceleration and deceleration capacities better predicted values of Apgar scores <7 and antenatal death (area under the curve for prediction of antenatal death: delta average acceleration capacity, 0.62 [confidence interval, 0.19–1.0]; delta short-term variation, 0.54 [confidence interval, 0.13–0.97]; P=.006; area under the curve for prediction Apgar <7: average deceleration capacity <24 hours before delivery, 0.64 [confidence interval, 0.52–0.76]; short-term variation <24 hours before delivery, 0.53 [confidence interval, 0.40–0.65]; P=.015). Neither phase-rectified signal averaging indices nor short-term variation showed predictive power for developmental disability at 2 years of age (Bayley developmental quotient, <95 or <85). CONCLUSIONS: The phase-rectified signal averaging method seems to be at least as good as short-term variation to monitor progressive deterioration of severely growth-restricted fetuses. Our findings suggest that for short-term outcomes such as Apgar score, phase-rectified signal averaging indices could be an even better test than short-term variation. Overall, our findings confirm the possible value of prospective trials based on phase-rectified signal averaging indices of autonomic nervous system of severely growth-restricted fetuses

Mantle thermal pulses below the Mid-Atlantic Ridge and temporal variations in the formation of oceanic lithosphere

A 20-Myr record of creation of oceanic lithosphere is exposed along a segment of the central Mid-Atlantic Ridge on an uplifted sliver of lithosphere. The degree of melting of the mantle that is upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of 3–4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the mantle is upwelling at an average rate of 25 mm yr-1, but this appears to vary through time. Slow-spreading lithosphere seems to form through dynamic pulses of mantle upwelling and melting, leading not only to along-axis segmentation but also to across-axis structural variability. Also, the central Mid-Atlantic Ridge appears to have become steadily hotter over the past 20 Myr, possibly owing to north–south mantle flow