Low-order partial-fraction (PF) fitting of optical dielectric functions from tabulated frequency data is investigated. Two rational function identification techniques are examined, viz., the ...Sanathanan-Koerner iteration and vector fitting, and it is found that these methods generate PF models of similar quality and both provide excellent starting solutions for further improvement by nonlinear optimizers. High-quality, wide-band PF models are obtained for several metals frequently encountered in plasmonic applications. These models are stable and well-suited for the finite-difference time-domain (FDTD) simulation of light interaction with nanostructures. An efficient FDTD updating scheme for PF media is also demonstrated.
The accuracy of the first-order multiplicative (Ott-Clemmow) and additive (van der Waerden) modified saddle point integration methods for the Sommerfeld problem of a vertical Hertzian dipole over a ...lossy half-space is investigated using two theoretically equivalent formulations with either a positive or a negative image term extracted. It is demonstrated that whereas the additive method leads to the same asymptotic field representation irrespective of the sign of the image, the multiplicative variant yields distinct results in these two cases, both of which differ from the unique result of the additive method. It is further found that the positive-image Ott-Clemmow method yields the well-known Norton formula, but the negative-image variant is inaccurate and predicts a zero field in the on-surface transmitter-receiver configuration. It is also demonstrated that the first-order multiplicative method yields an incomplete representation of the first order in the inverse distance.
The aim of this study was the assessment of progressive low-dose sodium bicarbonate (NaHCO
) supplementation on the anaerobic indices in two bouts of Wingate tests (WT) separated by ...wrestling-specific performance test and assessing the gender differences in response. Fifty-one (18 F) wrestlers completed a randomized trial of either a NaHCO
(up to 100 mg·kg
) or a placebo for 10 days. Before and after treatment, athletes completed an exercise protocol that comprised, in sequence, the first WT
, dummy throw test (DT), and second WT
. The number of completed throws increased significantly in males from 19.3 ± 2.6 NaHCO
to 21.7 ± 2.9 NaHCO
. ΔWT
-WT
improved particularly in the midsection of 30-s WT on NaHCO
. However, no significant differences were found in peak power (PP), power drop (PD) and average power (AP) (analyzed separately for each WT), and ΔWT
-WT
in PP and PD. Interaction with gender was significant for AP, PP and PD, every second of WT
and WT
, as well as DT test. In conclusion, our study suggests that the response to NaHCO
may be gender-specific and progressive low-dose NaHCO
supplementation allows the advantageous strengthening of wrestling-specific performance in males. It can also lead to maintenance of high anaerobic power mainly in the midsection of the 30-s Wingate test.
The problem of a vertical Hertzian dipole radiating in the presence of a lossy conducting halfspace, first formally solved by Sommerfeld in 1909, is revisited. Using rigorous operator theory concepts ...and the characteristic Green function procedure, alternative field representations are developed and their merits discussed. A closed-form asymptotic expression for the surface field is also derived and the role of the Zenneck and surface plasmon (SP) waves is elucidated. Numerical results are presented to validate the theory, including examples from radio to THz frequencies.
A robust and efficient method is presented for the computation of the electromagnetic modes supported by planar multilayer waveguides that may comprise lossy, active, plasmonic, and uniaxial media, ...including graphene sheets. Pole-free and numerically stable dispersion functions (DFs) are developed for various shielding configurations using the <inline-formula> <tex-math notation="LaTeX">S </tex-math></inline-formula>-matrix formulation. The modal propagation constants are computed by the Cauchy integration method on the four-sheeted Riemann surface, using the derivative of the DF for greater reliability. Since analytical derivatives of the S-parameters are difficult to obtain, automatic differentiation is employed, implemented by operator overloading in modern Fortran. The method is validated using various benchmark problems found in the literature.
The flame of eternity Michalski, Krzysztof; Benjamin Paloff
2007., 20111205, 2011, 2012-01-01
eBook
The Flame of Eternity provides a reexamination and new interpretation of Nietzsche's philosophy and the central role that the concepts of eternity and time, as he understood them, played in it. ...According to Krzysztof Michalski, Nietzsche's reflections on human life are inextricably linked to time, which in turn cannot be conceived of without eternity.
Large-scale failures of electric power systems (blackouts) have been the subject of intensive research in most countries for several years. This research aims primarily at seeking solutions to ...improve the reliability of the operation of power systems and the development of effective strategies to protect critical infrastructure from the effects of energy shortages and power cuts. In contrast, systematic research on crisis management and civil protection under conditions of prolonged blackout has been undertaken in Europe only recently, and these extremely important aspects of energy security have been delayed by the COVID-19 crisis. The ability of the Polish crisis management system to cope with the consequences of long-term, large-scale shortages and interruptions in the supply of electricity, as well as the consequences of possible failures in this field, has not been systematically examined to date. This issue is of growing strategic importance, not only from the point of view of security and defence policy, but also economic cooperation in Central and Eastern Europe. Poland’s infrastructural security must be considered in a broad regional and supra-regional context. A long-term lack of electricity in a large area of Poland would undermine the stability of the entire national security system, destabilising the region and supranational security systems. Apart from objective reasons, intentional attacks on the links of such a chain cannot be ruled out. Poland is the leader of this region, a frontline country in the NATO-Russia conflict, as well as a liaison state that provides the Baltic states—being EU and NATO members—with a land connection to Western Europe. In view of the growing risk of blackout, the importance of the problem and the existence of a cognitive gap in this field, we evaluated the Polish crisis management system in terms of its ability to respond to the effects of a sudden, long-term, large-scale blackout. Methodologically, we adopted a systems approach to security management. In order to estimate the consequences of a blackout, we used analogue forecasting tools and scenario analysis. By analysing previous crisis situations caused by blackouts and local conditions of vulnerability to such events, we formulated basic preparedness requirements that a modern crisis management system should meet in the face of the growing risk of blackouts. A review of strategic documents and crisis planning processes in public administration allowed us to identify deficits and weaknesses in the Polish crisis management system. On this basis we formulated recommendations whose implementation shall improve the ability of the national security system to face such challenges in the future.
Cross-training is a high-intensity functional training (HIFT) with multiple workout modalities. Despite the increasing number of studies in HIFT, there is still no validated test to measure its ...specific performance. It would also be advisable to determine whether selected cross-training workouts can implement a stimulus corresponding to maximize aerobic work. For these reasons, the purpose of our study was to evaluate the repeatability and reliability of Fight Gone Bad (FGB) workout and to assess its relationship with aerobic fitness. Twenty-one cross-training participants (9 females) finished the study protocol which included three two-day measurement sessions separated by 10 days. During each session, participants had their body composition measured, and they performed two exercise tests. The first test was an incremental cycling test to measure aerobic fitness, and the second was a cross-training specific FGB workout performed the next day. Reliability and repeatability were calculated from the three measurements. The total FGB Score (FGB
) showed excellent reliability (ICC 0.9, SEM 6%). Moreover, FGB
was strongly correlated with aerobic fitness (i.e., time to exhaustion (T
, R
= 0.72), maximal workload (W
, R
= 0.69), time to gas exchange threshold (T
, R
= 0.68), and peak oxygen uptake (VO
, R
= 0.59). We also found that agreement between standardized FGB and standardized aerobic performance indices such as T
, VO
, W
, maximum heart rate, T
, and workload at gas exchange threshold was high by the Bland-Altman method. In conclusion, FGB is a reliable test that can be used in order to measure changes in cross-training performance caused by an intervention. Moreover, FGB is strongly correlated to aerobic fitness.
In the above paper <xref ref-type="bibr" rid="ref1">1 , <xref rid="deqn32" ref-type="disp-formula">(32) was misprinted and should be corrected as follows:
The approximate solutions of King and Norton-the latter as extended by Bannister-for the problem of a vertical Hertzian dipole radiating over a lossy ground are compared and their equivalence is ...established.
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