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We evaluate the triple correlation of eigenvalues of the Laplacian on generic flat tori in an averaged sense. As two consequences we show that (a) the limit inferior (resp. limit superior) of the triple correlation is almost surely at most (resp. at least) Poissonian, and that (b) almost all flat tori contain infinitely many gaps in their spectrum that are at least 2:006 times longer than the average gap. The significance of the constant 2:006 lies in the fact that there exist sequences with Poissonian pair correlation and with consecutive spacings bounded uniformly from above by 2, as we also prove in this paper. Thus our result goes beyond what can be deduced solely from the Poissonian behavior of the pair correlation. [ABSTRACT FROM AUTHOR]

Using the experimental data in nuclear computing to verify the calculation methods and tools based on numerical and statistical methods has many benefits such as illustrating the quality, ensuring the capabilities, and validating computer codes. Simulation by computer tools is also applicable in the safety analysis of research reactors. In this research, the computer tool (MCNPX 2.7.0: 2011) was verified against the experimental data of neutron flux and spectrum on the sample position of the Tehran Research Reactor (TRR) neutron imaging system by the neutron activation method. To determine the benchmark specifications, the simulation of the system was done at the first step by considering a well-defined facility geometric, material specification and reactor core configuration, fuel elements, and radiation facility (beam tubes and collimator, reactor core, and neutron imaging components). Then the flux and neutron spectrum at the sample position were calculated. In the second step, a set of In (bare and covered by cd) and Au foils and a set of Au, Ni, Ti, and Zr, were placed and exposed almost in front of the reactor E beam tube. The neutron energy spectrum was unfolded by calculating the saturation activity of each foil by SAND-II code, and the neutron flux was calculated. A comparison of the results obtained in two steps shows a relatively good and acceptable agreement (Max. 30% deviation) between the flux and the shape of the flux profile obtained from calculations and experimental data. [ABSTRACT FROM AUTHOR]

Modern cloud native applications are generally built with a microservice architecture. To tackle various performance problems among a large number of services and machines, an end‐to‐end tracing tool is always equipped in these systems to track the execution path of every single request. However, it is nontrivial to conduct root cause analysis of anomalies with such a large volume of tracing data. This paper proposes a novel system named TraceRank to identify and locate abnormal services causing performance problems with dis‐aggregated end‐to‐end traces. TraceRank mainly includes an anomaly detection module and a root cause analysis module. The root cause analysis procedure is triggered when an anomaly is detected. To fully leverage the information provided by the tracing data, both the spectrum analysis and the PageRank‐based random walk methods are introduced to pinpoint abnormal services. The experiments in TrainTicket and Bookinfo microservice benchmarks and a real‐world system show that TraceRank can locate root causes with 90% in Precision and 86% in Recall. TraceRank has up to 10% improvement compared with several state‐of‐the‐art approaches in both Precision and Recall. Finally, TraceRank has good scalability and a low overhead to adapt to large‐scale microservice systems. [ABSTRACT FROM AUTHOR]

Magnetic nondestructive evaluation (NDE) for ferromagnetic steel using spectrum analysis of induced voltage at a pickup coil and magnetic flux density has been studied. A voltage induced at the pickup coil was measured, and the corresponding magnetic flux density was calculated. Then, their frequency spectrums were obtained through a Fourier analysis. For deformed specimen, higher harmonic components decrease as compared with undeformed specimen. The wave distortion factor for the induced voltage and the magnetic flux density were defined and evaluated. Those values decrease with increasing reduction ratio of the specimen; this means the waveforms of induced voltage and magnetic flux density for a less deformed specimen has a large distortion in those waves. Those changes reflect a nonlinearity of the magnetization curves of the specimen. The results in this study indicate a potential of magnetic NDE using spectrum analysis of measurement wave forms. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mathematics, Mechanics & Computer Science is the property of Al-Farabi Kazakh National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A detailed analysis of the bremsstrahlung spectrum at nonrelativistic electron scattering on argon and xenon is carried out. It is shown that the approximate formulas widely used for the description of bremsstrahlung spectra lead to predictions that significantly differ from the exact results. In the limit when the photon frequency tends to zero, a rigorous proof of the relationship between the spectrum of the bremsstrahlung with a transport cross section of electron scattering on an atom is given. This proof does not require any assumptions about the dependence of the scattering phases on energy. For electron energies lower than the luminescence threshold, it is shown that the predictions for a number of radiated photons obtained by the exact formula are in good agreement with the available experimental data. [ABSTRACT FROM AUTHOR]

The contribution of this research work focuses on understanding the biological behavior of time-varying electric fields, specifically in the eyeball, by proposing sensitive frequency ranges, specifically for primary open-angle glaucoma POAG and RP retinitis pigmentosa. These ranges were obtained from the analysis of the frequency spectrum of the signals used by other authors in transcorneal electrical stimulation TES therapies. This analysis was performed using an algorithm proposed in this work. The frequency spectra of the signals used in the TES were also compared with the frequency response of the cellular behavior evoked by genestein drug, in order to compare the frequency characteristics of the signals applied in the TES and the biological response of the drug. which causes the same effect in POAG. [ABSTRACT FROM AUTHOR]

This paper describes the design and execution of a wavemaker system (piston type) in the Dokuz Eylül University Hydraulic Laboratory flume to perform hydraulic model tests using regular and irregular waves. In this study, we will focus on generating the irregular waves from the target JONSWAP spectrum using an adjusted random phase method; also, the control software of the wavemaker is described. An identical numerical channel wave to the physical flume was modeled to compare and observe the irregular wave profile using Flow 3D, one of the advanced computational fluid dynamics (CFD) software. The paddle movement was validated by comparing the experimentally converted irregular wave surface elevations to the wave spectrum to the numerical models of several waves. [ABSTRACT FROM AUTHOR]

The effectiveness of the conventional friction pendulum isolator (FPI) is limited in complex geographical environments and unpredictable earthquake events due to its complex frictional properties and the requirement for a unified setup target. With a view to addressing the aforementioned issues, in conjunction with an adaptive variable friction pendulum isolator (AVFPI), a simple and practical mechanical model is proposed. After applying the mechanical model with a friction-dependent influence model, an improved response spectrum analysis procedure (IRS) is proposed for variable friction pendulum isolation systems. Notably, the proposed procedure allows for the consideration of the effects of variations in velocity, temperature, and pressure on the friction characteristics without the necessity for nonlinear response history analysis (NRHA). The procedure commences with obtaining a numerical model of friction dependency through friction material examinations, then proceeds to verifying the reliability of both the friction dependency and mechanical model through prototype tests of AVFPIs. The following study presents a proposed correction method that depends on random vibration theory to establish a functional relationship between the pseudo-velocity spectrum and the velocity spectrum. Additionally, an association is established between the peak velocity and the generation of frictional heat. Finally, the procedure is evaluated based on the results of an NRHA that takes friction dependence into account through a numerically variable friction pendulum isolation system. The results of the study indicate that the IRS provides a more accurate and secure assessment of the isolator displacement at various temperatures than the response spectrum method, which does not account for the influence of frictional dependency. The failure to consider the influence of friction dependency in high-temperature environments produces an underestimation of isolator slip displacement and a subsequent increase in failure rates. The Polytetrafluoroethylene (PTFE) friction materials that are currently in widespread use exhibit a strong correlation with friction dependence and, as a consequence, cause relatively large displacements at temperatures that are both low and high. The results of this study present an opportunity to expand how response spectrum analysis techniques can be applied to friction pendulum isolation systems. • A simplified mechanical hysteresis model for adaptive variable friction pendulum isolators is proposed. • A new friction material was tested and the velocity, pressure stress and temperature dependence expressions were obtained for the new friction material. • An expression for the friction coefficient of an adaptive variable friction pendulum isolator that takes into account the effects of velocity, pressure stress, and temperature dependence during nonlinear response history analysis is presented. • An improved method for analysing the response spectrum of variable friction pendulum isolation systems is proposed. Notably, the proposed procedure allows the consideration of the effects of velocity, temperature and pressure variations on the friction characteristics without the necessity to proceed to a nonlinear response history analysis (NRHA). • In the improved method of response spectrum analysis of variable friction pendulum isolation system, based on the correction method of stochastic vibration theory, the functional relationship between the pseudo velocity spectrum and the velocity spectrum is established, and a simplified calculation method for calculating frictional heat by peak velocity response is proposed. [ABSTRACT FROM AUTHOR]

The article discusses the principles of construction of electron-optical converters of spectra and scales of images, the description of their structures and methods of theoretical research. It is noted that electron-optical converters are used to visualize images from the infrared or ultraviolet regions of the light spectrum invisible to ordinary vision, and electron microscopes are used to transfer images from invisible micron or submicron sizes to the area of sizes convenient for visual studies. The paper also notes possible ways to improve these devices. [ABSTRACT FROM AUTHOR]

In this article, we introduce the notion of biorthgonoal nonuniform multiresolution analysis on the spectrum Λ=0,r/N+2ℤ, where N ≥ 1 is an integer and r is an odd integer with 1 ≤ r ≤ 2N − 1 such that r and N are relatively prime. We first establish the necessary and sufficient conditions for the translates of a single function to form the Riesz bases for their closed linear span. We provide the complete characterization for the biorthogonality of the translates of scaling functions of two nonuniform multiresolution analysis and the associated biorthogonal wavelet families. Furthermore, under the mild assumptions on the scaling functions and the corresponding wavelets associated with nonuniform multiresolution analysis, we show that the wavelets can generate Reisz bases. [ABSTRACT FROM AUTHOR]

Background: Hypoxia is associated with abnormal cell apoptosis in trophoblast cells, which causes fetal growth restriction and related placental pathologies. Few effective methods for the prevention and treatment of placenta-related diseases exist. Natural products and functional foods have always been a rich source of potential anti-apoptotic drugs. Nobiletin (NOB), a hexamethoxyflavonoid derived from the citrus pomace, shows an anti-apoptotic activity, which is a non-toxic constituent of dietary phytochemicals approved by the Food and Drug Administration. However, their effects on hypoxia-induced human trophoblast cells have not been fully studied. Objective: The aim of this study was to investigate the protective effects of NOB on hypoxia-induced apoptosis of human trophoblast JEG-3 and BeWo cells, and their underlying mechanisms. Design: First, the protective effect of NOB on hypoxia-induced apoptosis of JEG-3 and BeWo cells was studied. Cell viability and membrane integrity were determined by CCK-8 assay and lactate dehydrogenase activity, respectively. Real Time Quantitative PCR (RT-qPCR) and Western blot analysis were used to detect the mRNA and protein levels of HIF1α. Propidium iodide (PI)-labeled flow cytometry was used to detect cell cycle distribution. Cell apoptosis was detected by flow cytometry with Annexin V-FITC and PI double staining, and the expression of apoptosis marker protein cl-PARP was detected by Western blot analysis. Then, the molecular mechanism of NOB against apoptosis was investigated. Computer molecular docking and dynamics were used to simulate the interaction between NOB and p53 protein, and this interaction was verified in vitro by Ultraviolet and visible spectrum (UV-visible spectroscopy), fluorescence spectroscopy and circular dichroism. Furthermore, the changes in the expression of p53 signaling pathway genes and proteins were detected by RT-qPCR and Western blot analysis, respectively. Results: Hypoxia treatment resulted in a decreased cell viability and cell membrane integrity in JEG-3 and BeWo cell lines, and an increased expression of HIF1α, cell cycle arrest in the G1 phase, and massive cell apoptosis, which were alleviated after NOB treatment. Molecular docking and dynamics simulations found that NOB spontaneously bonded to human p53 protein, leading to the change of protein conformation. The intermolecular interaction between NOB and human p53 protein was further confirmed by UV-visible spectroscopy, fluorescence spectroscopy and circular dichroism. After the treatment of 100 μM NOB, a down-regulation of mRNA and protein levels of p53 and p21 and an up-regulation of BCL2/BAX mRNA and protein ratio were observed in JEG-3 cells; however, there was also a down-regulation of mRNA and protein levels observed for p53 and p21 in BeWo cells after the treatment of NOB. The BCL2/BAX ratio of BeWo cells did not change after the treatment of 100 µM NOB. Conclusion: NOB attenuated hypoxia-induced apoptosis in JEG-3 and BeWo cell lines and might be a potential functional ingredient to prevent pregnancy-related diseases caused by hypoxia-induced apoptosis. These findings would also suggest the exploration and utilization of citrus resources, and the development of citrus industry. [ABSTRACT FROM AUTHOR]

The polarity of light and dark in the treatment of the Newtonian spectrum and the inverse spectrum is studied further and the validity of heterogeneity of light and darkness in relation to Goethe's views is examined. In order to clarify the reality of the "darkness rays", the experimentum crucis is re-evaluated. It is shown that the commonly accepted analysis contains assumptions in the choice of the spectrum and background, which mask the inherent dynamic of the spectrum. The relation between colour and wavelength is re-examined with respect to the immutability and specific refrangibility of colour. It is then shown that both these properties are approximations that apply under the specific conditions that have later become standardized in spectroscopy, leading to a consensus regarding the relation of wavelength to colours of one particular spectrum. This consensus has resulted in the study of colour diverging into spectroscopy and colour physiology. As an alternative, the basis of the dichotomy postulated by Müller is studied, leading to the realization that the resolution of this dichotomy was begun by Goethe with the idea of turbidity. A further study shows that turbidity resolves the apparent incompatibility of light and dark. [ABSTRACT FROM AUTHOR]

We shed some light on the Pythagorean relation for operator established in [7] and we study its relationship with the maximal numerical range. We then get some information of maximal numerical ranges of selfadjoint operators. This allows us to show, contrary to the closure of the numerical range, the non-comtinuity in the sens of Hausdorff of the maximal numerical range. [ABSTRACT FROM AUTHOR]

Floristic diversity is specific for an ecological area and plays an important role in every ecosystem. The present study deals with floristic composition and life form analysis of vascular plants, which grow in Gargi college campus and are compared with Raunkiaer's life form spectrum. The whole campus area was surveyed during 2018 to 2019 for the record of plant specimens. Plant species growing wild as well as cultivated have been listed belonging to vascular plants (angiosperm, gymnosperm and pteridophyte). A total of 199 plant species of 172 genera and 69 families were recorded, including 2 pteridophytes, 7 gymnosperms and 190 angiosperms (23% monocots and 77% dicots). Fabaceae was found as the most dominant family in the flora of the project area that contributed 17 species, followed by Apocynaceae (10 species), Asteraceae, Euphorbiaceae, Moraceae and Poaceae (9 species), Asparagaceae and Malvaceae (8 species), Arecaceae (7 species) while rest of the families shared 1-6 species. It was recorded that herbs were dominating fraction in the floristic composition that contributed 38%, followed by trees (32%), shrubs (16%), climbers (5%) and shrub to trees (4%), whereas rest of 4 categories were in the range of 3- 0.005%. Phanerophytes were the most abundant life form that constituted 55.28% of the total flora, followed therophytes by (29.15%), chamaephytes (6.53%), geophytes (5.03%) hemicryptophytes (3.02%), and hydrophytes (1.01%). [ABSTRACT FROM AUTHOR]

We introduce new concepts of functional analysis: Hausdorff spectrum and Hausdorff limit or H-limit of Hausdorff spectrum of locally convex spaces with point of view using sheaves theory. Particular cases of regular H-limit are projective and inductive limits of separated lo- cally convex spaces. The class of H-spaces contains Fréchet spaces and is stable under the operations of forming countable inductive and pro- jective limits, closed subspaces and factor-spaces. Besides, for H-space the strengthened variant of the Closed Graph Theorem holds true. The space of germs of holomorphic functions on connected bounded subset will be provided with the topology (in general not separated) of uni- form convergence on the compact subsets and with the locally convex topology of the H-limit. We also present an essentially new approach to the study of sheaves based on the notion of Hausdorff spectra associated with the presheaf. [ABSTRACT FROM AUTHOR]

After introduction of rotavirus vaccine, other pathogens might become leading causes of hospitalizations for severe diarrhea among children <5 years of age. Our study in 33 hospitals in 7 countries found acute gastroenteritis accounted for most (84%) reported hospitalizations of children with diarrhea. Bloody and persistent diarrhea each accounted for <1%. [ABSTRACT FROM AUTHOR]

An improved analytical model (G-factor model) for the Rayleigh–Brillouin scattering (RBS) spectrum of gases is proposed and discussed based on RBS spectra of nitrogen. Three analytical models (G3, V3, and G-factor models) were compared with the spontaneous RBS experimental data and coherent RBS simulation data based on Pan's S7 model. The results show that the proposed model has a larger scope of application as compared to the G3 model, and offers less multivalued solutions compared to the V3 model. In addition, this analytical model provides a better representation of the profiles than the Tenti S6 model. This novel analytical model has fewer parameters and more stable fitting results. It maintains a high fitting accuracy and has a larger scope of application compared to the other analytical models. [ABSTRACT FROM AUTHOR]

The energetic electron spectra of Saturn's radiation belts are studied using Cassini's 13 years of measurements by the Magnetosphere Imaging Instrument/Low Energy Magnetospheric Measurement System detector. We find that between L shells (L) of 10 and 4.5 the differential flux spectrum of 0.3‐ to 1.6‐MeV electrons evolves from a single power law to two power law functions separated at an energy cutoff (Ec). We show that inside L∼8, Ec has an L shell dependence that tracks consistently the energy of corotation drift cancelation (or resonance) ECDR, that is, the energy at which magnetic electron drifts and azimuthal corotation cancel, and is not associated with the absorbing effects of Saturn's moons. Ec also deviates from what conservation of the first adiabatic invariant would dictate. Our results verify that electrons around ECDR can be transported radially very efficiently by variable convective flows, such as those related to the noon‐midnight electric field in Saturn's magnetosphere. Plain Language Summary: The electron radiation belt of Saturn is a region that reaches out several planetary radii outward of the main rings and contains significant intensities of relativistic electrons. It can be rather dynamic in terms of particle intensity and spatial extent. How these electrons are supplied is still debated, as several viable physical processes have been proposed. Using Cassini's 13 years of observations, we verified that a special class of energetic electrons, whose westward magnetic drift cancels out with the eastward corotation imposed by the planet, could be transported and accelerated very effectively. At the energy where this drift cancelation occurs, the intensities of energetic electrons show a sharp change in intensity, as would be expected if this transport process dominates over others mechanisms which invoke interactions of electrons with high‐frequency waves. The same acceleration process may be readily applicable to Jupiter, as its electron radiation belts are exposed to a qualitatively similar environment as of Saturn's. This implication would be crucial for establishing realistic, physical electron radiation belt models for the outer planets. Key Points: Electron spectra around 1 MeV are described with two power law functions separated at a cutoff energyThe L shell dependence of the cutoff energy tracks consistently that of corotation drift cancelation (or resonance)Transport and acceleration of ∼1‐MeV electrons is affected by variable convective flows [ABSTRACT FROM AUTHOR]

Abstract A (1 , ≤ ℓ) -identifying code in digraph D is a dominating subset C of vertices of D , such that all distinct subsets of vertices of D with cardinality at most ℓ have distinct closed in-neighborhoods within C. As far as we know, it is the very first time that the spectral graph theory has been applied to the identifying codes. We give a new method to obtain an upper bound on ℓ for digraphs. The results obtained here can also be applied to graphs. [ABSTRACT FROM AUTHOR]

A bounded operator T in a Banach space X is said to satisfy the descent spectrum equality, if the descent spectrum of T as an operator on X coincides with the descent spectrum of T as an element of the algebra B (X) of all bounded linear operators on X. In this paper, we give some conditions under which the equality σ desc (T) = σ desc (T , B (X)) holds for a single operator T. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the operator ... on the sequence space c0 where b0, b1, b2 are nonrzero and the nonzero diagonals are the entries of an oscillatory sequence. [ABSTRACT FROM AUTHOR]

Abstract Electromagnetic spectrum for wireless communications is fully allocated by regulatory authorities, but this does not mean that it is fully utilized. Demand for greater capacity and new services requires new regulatory and technical models for spectrum sharing. This paper develops a regulatory model denoted the dynamic policy license. The dynamic policy license combines the assurances to licensees that come from holding a fixed license while maintaining regulatory flexibility. A dynamic policy license is similar to a traditional spectrum license that specifies a bandwidth, power, center frequency, location, and other parameters. However, one or more of these parameters is subject to change by the regulator over time. The allowed changes are restricted by the license to provide assurances and predictability to the licensee. The opportunities and challenges that this presents to both regulators and licensees is described. For instance, the dynamic policy license can be a regulatory tool for more aggressive spectrum sharing. Highlights • Electromagnetic spectrum is fully allocated but not fully utilized. • To meet increasing demand, new regulatory and technical sharing models are needed. • This paper develops a regulatory model called the dynamic policy license. • It provides licensing flexibility for the regulator and certainty for the licensee. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the operator ... on the sequence space c0 where the non-zero diagonals are the entries of an oscillatory sequence. [ABSTRACT FROM AUTHOR]

The approximation of the eigenvalues and eigenfunctions of an elliptic operator is a key computational task in many areas of applied mathematics and computational physics. An important case, especially in quantum physics, is the computation of the spectrum of a Schrödinger operator with a disordered potential. Unlike plane waves or Bloch waves that arise as Schrödinger eigenfunctions for periodic and other ordered potentials, for many forms of disordered potentials the eigenfunctions remain essentially localized in a very small subset of the initial domain. A celebrated example is Anderson localization, for which, in a continuous version, the potential is a piecewise constant function on a uniform grid whose values are sampled independently from a uniform random distribution. We present here a new method for approximating the eigenvalues and the subregions which support such localized eigenfunctions. This approach is based on the recent theoretical tools of the localization landscape and effective potential. The approach is deterministic in the sense that the approximations are calculated based on the examination of a particular realization of a random potential, and predict quantities that depend sensitively on the particular realization, rather than furnishing statistical or probabilistic results about the spectrum associated to a family of potentials with a certain distribution. These methods, which have only been partially justified theoretically, enable the calculation of the locations and shapes of the approximate supports of the eigenfunctions, the approximate values of many of the eigenvalues, and of the eigenvalue counting function and density of states, all at the cost of solving a single source problem for the same elliptic operator. We study the effectiveness and limitations of the approach through extensive computations in one and two dimensions, using a variety of piecewise constant potentials with values sampled from various different correlated or uncorrelated random distributions. [ABSTRACT FROM AUTHOR]

Theory of the spectrum of localized two-level quasi-particle renormalized due to interaction with polarization phonons at cryogenic temperature is developed using the generalized method of Feynman-Pines diagram technique. Using the procedure of partial summing of infinite ranges of the main diagrams, mass operator is obtained as a compact branched chain fraction, which effectively takes into account multi-phonon processes. It is shown that multi-phonon processes and interlevel interaction of quasiparticle and phonons cardinally change the renormalized spectrum of the system depending on the difference of energies of two states, which either resonates with phonon energy or does not. The spectrum of non-resonant system contains renormalized energies of the main states and two similar infinite series of groups of phonon satellite levels. The spectrum of a resonant system contains a renormalized ground state and infinite series of satellite groups. [ABSTRACT FROM AUTHOR]

Discharge phenomena can occur when metals are exposed to microwave radiation. The mechanism of the discharge can be effectively studied by using spectral analysis. In this study, a reactor that can withstand long-term high pressure was used in combination with a spectrometer to investigate the effects of pressure and other parameters on the microwave metal discharge plasma. It was observed that the increase of radiation power, pressure, and metal wire diameter can have positive effects on the intensity of spectral lines. If other experimental conditions remain unchanged, the spectral lines and discharge intensity exhibit dynamic changes because the wire melts and changes its shape under the high local temperature associated with discharge. Because factors like radiation power and pressure can enhance the intensity of the plasma significantly, they can be reasonably utilized to accelerate the chemical reactions or improve the degradation rate of pollutants, e.g. in microwave wet oxidation applications. [ABSTRACT FROM AUTHOR]

We establish a new method for obtaining nonconvex spectral enclosures for operators associated with second‐order differential equations z¨(t)+Dz˙(t)+A0z(t)=0 in a Hilbert space. In particular, we succeed in establishing the existence of a spectral gap, which is the first result of this kind since the seminal results of Krein and Langer for oscillations of damped systems. While the latter and other spectral bounds are confined to dampings D that are symmetric and dominated by A0, we allow for accretive D of equal strength as A0. To achieve these results, we prove new abstract spectral inclusion results that are much more powerful than classical numerical range bounds. Two different applications, small transverse oscillations of a horizontal pipe carrying a steady‐state flow of an ideal incompressible fluid and wave equations with strong (viscoelastic and frictional) damping, illustrate that our new bounds are explicit. [ABSTRACT FROM AUTHOR]

Stochastic acceleration of cosmic rays in second order Fermi processes is usually considered too slow to reach ultra-high energies, except in specific cases. In this paper we present the energy spectrum obtained from second order Fermi acceleration in highly turbulent magnetic fields as e.g. found in the outskirts of AGN jets in situations where it can be sufficiently fast to accelerate particles to the highest observed energies. We parametrize the resulting non-power-law spectra and show that these can describe the cosmic ray energy spectrum and mass-composition data at the highest energies if propagation effects are taken into account. [ABSTRACT FROM AUTHOR]

Karoubi's density theorem was first proved in Benayat's thesis and then cited and used in several books and articles. As K-theory is a special case of hermitian "L-theory, a natural question is whether such a theorem is still true in the latter theory. The purpose of this article is to show that it is indeed the case. [ABSTRACT FROM AUTHOR]

The spectra of the generalized difference operator B(r, s) in various sequence spaces have been investigated by many authors. Nevertheless, to the best of our knowledge, no contribution has appeared so far to study the problem in the common sequence spaces and and . In this paper, we fill this gap by analysing the spectrum of the operator B(r, s) on and h. Also, we explore some ideas of how to study the problem for a general form of the operator, namely, the operator . [ABSTRACT FROM AUTHOR]

Abstract: Spectra of comet 2P/Encke obtained on November 15 and 22, 2003, in wavelength ranges of λ = 410-580 and 560-720 nm with the Universal Astronomical Grating Spectrograph (UAGS) mounted at the 1-m Zeiss-1000 telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences is analyzed. The spectral resolution is 0.5 nm. In the cometary coma, the emission bands of C2, CN, CH, and NH2 molecules were detected. The normalized spectral gradient of the reflectivity is (11.95 ± 3.45) and (7.90 ± 2.81)% per 100 nm in wavelength bands of 450-567 and 565-676 nm, respectively. The values of the parameter Afρ are (77 ± 9), (81 ± 9), and (79 ± 9) cm for the BC, GC, and RC continuum filters, respectively, which is indicative of a very low dust content in comet Encke. With the Haser model, we determined the production rate of gas molecules at (1.12 × 1025) and (3.82 × 1024) mol/s for C2 (Δν = 0) and NH2 (0,10,0) molecules, respectively. [ABSTRACT FROM AUTHOR]

We study the impact of spectrum auction design on the prices paid by telecommunications operators for two decades across 85 countries. Our empirical strategy combines information about competition in the local market, the level of adoption and a wide range of socio-economic indicators and process specific variables. Using a micro dataset of almost every mobile spectrum auction performed so far—both regional and national—we show that auction design affects final prices paid. Two designs (SMRA with augmented switching and CCA with core pricing) result in auctions with systematically higher normalized returns. Further, we document that spectrum ownership appears to affect prices paid in subsequent auctions. We discuss the mechanisms of cost minimization and foreclosure faced by operators in different regulatory environments. Our findings have implications for policy-makers and regulators. [ABSTRACT FROM AUTHOR]

The records from 161 identical broadband seismic stations located in different regions of the world after the strong earthquakes off Sumatra Island on December 26, 2004 with magnitude M = 9.1, in Chile on February 27, 2010 with M = 8.8, and the Tohoku earthquake in Japan on March 11, 2011 with M = 9.0 are studied. Oscillations with a period of ~11 h are analyzed. They are observed as pulsations in the free radial oscillations of the Earth lasting more than one week. The stations located a few hundred kilometers apart from each other demonstrate identical records. As the distance between the stations becomes larger, the structure of the records becomes different. At interstation distances of about 3800 km, the records at the stations have opposite phases, and at distances of ~7600 km, the phases coincide. This is reflected in the spatial structure of the areas of the positive and negative phases of the oscillations on the Earth’s surface. This structure recurs at the same time instant after the three considered earthquakes, which indicates that this effect is independent of the properties of the sources. The spatial positions of the areas of positive and negative phases are also not correlated to the geological conditions in the vicinity of the stations which are located both in the subduction zone and within the platform. The structure of the pulsations and their spatial distribution differ from the variations of the Earth’s tides. [ABSTRACT FROM AUTHOR]

The 2001 Mw 7 . 7 Bhuj mainshock seismic sequence in the Kachchh area, occurring during 2001 to 2012, has been analyzed using mono-fractal and multi-fractal dimension spectrum analysis technique. This region was characterized by frequent moderate shocks of M w ≥ 5 . 0 for more than a decade since the occurrence of 2001 Bhuj earthquake. The present study is therefore important for precursory analysis using this sequence. The selected long-sequence has been investigated first time for completeness magnitude Mc 3.0 using the maximum curvature method. Multi-fractal Dq spectrum ( D q ∼ q ) analysis was carried out using effective window-length of 200 earthquakes with a moving window of 20 events overlapped by 180 events. The robustness of the analysis has been tested by considering the magnitude completeness correction term of 0.2 to Mc 3.0 as Mc 3.2 and we have tested the error in the calculus of D q for each magnitude threshold. On the other hand, the stability of the analysis has been investigated down to the minimum magnitude of M w ≥ 2 . 6 in the sequence. The analysis shows the multi-fractal dimension spectrum D q decreases with increasing of clustering of events with time before a moderate magnitude earthquake in the sequence, which alternatively accounts for non-randomness in the spatial distribution of epicenters and its self-organized criticality. Similar behavior is ubiquitous elsewhere around the globe, and warns for proximity of a damaging seismic event in an area. OS: Please confirm math roman or italics in abs. [ABSTRACT FROM AUTHOR]

To reduce cost, increase resolution, and reduce errors due to changing light intensity of the VIS SPEC, a new technique is proposed which applies the Kalman algorithm along with a simple hardware setup and implementation. In real time, the SPEC automatically corrects spectral data errors resulting from an unstable light source by adding a photodiode sensor to monitor the changes in light source intensity. The Kalman algorithm is applied on the data to correct the errors. The light intensity instability is one of the sources of error considered in this work. The change in light intensity is due to the remaining lifetime, working time and physical mechanism of the halogen lamp, and/or battery and regulator stability. Coefficients and parameters for the processing are determined from MATLAB simulations based on two real types of datasets, which are mono-changing and multi-changing datasets, collected from the prototype SPEC. From the saved datasets, and based on the Kalman algorithm and other computer algorithms such as divide-and-conquer algorithm and greedy technique, the simulation program implements the search for process noise covariance, the correction function and its correction coefficients. These components, which will be implemented in the processor of the SPEC, Kalman algorithm and the light-source-monitoring sensor are essential to build the Kalman corrector. Through experimental results, the corrector can reduce the total error in the spectra on the order of 10 times; for certain typical local spectral data, it can reduce the error by up to 60 times. The experimental results prove that accuracy of the SPEC increases considerably by using the proposed Kalman corrector in the case of changes in light source intensity. The proposed Kalman technique can be applied to other applications to correct the errors due to slow changes in certain system components. [ABSTRACT FROM AUTHOR]

Tm 3+ and Dy 3+ co-doped Ba m Sr 1−m MoO 4 polycrystals were synthesized by a low temperature combustion method. The X-ray diffraction patterns showed that the phosphors were mainly composed of the SrMoO 4 phase. From scanning electron microscopy detection, the Ba 0.05 Sr 0.84 MoO 4 :0.05Tm 3+ 0.06Dy 3+ phosphor showed ellipsoid particles with an average diameter of approximately 0.5 µm. When excited by proper ultraviolet light, the co-doped Ba 0.05 Sr 0.95 MoO 4 samples showed a blue emission band located at 454 nm attributed to the 1 D 2 → 3 F 4 transition of the Tm 3+ ions and an yellow band located at 573 nm attributed to the 4 F 9/2 → 6 H 1/2 transition of Dy 3+ ions. White-light emission was achieved with 5 mol% Tm 3+ and 6 mol% Dy 3+ co-doped in the Ba 0.05 Sr 0.84 MoO 4 crystal with chromaticity coordinates of x=0.323 and y=0.354, and a color temperature of Tc =5910 K upon excited of 354 nm. [ABSTRACT FROM AUTHOR]

In this paper we study the spectra of uniform hypertrees by using the generalized weighted incident matrix. We show that λ is a nonzero eigenvalue of the hypertree H corresponding to an eigenvector with all elements nonzero if and only if λ is a root of the polynomial φ ( H ) = ∑ i = 0 m ( − 1 ) i | M i | x ( m − i ) r , where | M i | is the number of matchings of order i in H . [ABSTRACT FROM AUTHOR]

We investigate anomalous localized resonance on the circular coated structure and cloaking due to it in the context of elastostatic systems. The structure consists of the circular core with constant Lame parameters and the circular shell with negative Lamé parameters proportional to those of the core. We show that there is a nonzero number k0 determined by Lamé parameters such that two nonempty eigenvalue sequences of the Neumann--Poincare operator associated with the structure converge to k0 and --k0, respectively, and derive precise asymptotics of the convergence. We then show by qualitative estimates based on asymptotics of eigenvalues that cloaking by anomalous localized resonance takes place if and only if the dipole-type source lies inside critical radii determined by radii of the core and the shell. The critical radii corresponding to k0 and --k0 are different. [ABSTRACT FROM AUTHOR]

This paper studies the variation of spectra of closed subspaces (i.e., linear relations) in Banach spaces under some perturbations. A concept of commutativity for subspaces in Banach spaces is introduced and its properties are studied. It is shown that boundedness of the inverse of a closed subspace is preserved under relatively bounded and small gap perturbations and perturbation about spectral condition, separately. By using these results, upper semi-continuity of spectra of closed subspaces is obtained and an error estimate of spectra of closed subspaces is given under bounded perturbation. In the special case that the space is a Hilbert space, invariance of self-adjointness of subspaces under relatively bounded and small gap perturbations and the variation of spectrum of a self-adjoint subspace under bounded and Hermitian perturbation are discussed. The results obtained in the present paper generalize the corresponding results for closed operators to closed subspaces and some of which weaken certain assumptions of the related existing results. [ABSTRACT FROM AUTHOR]

The WRC-15 was the peak of African participation and contributions in the ITU-R with the first African to chair a WRC. However, there have been different elements within the international radio regulations that did have a restrictive influence on the African international spectrum policy during WRC-15. In particular, the discussion within ITU-R Region 1 highlighted different requirements between the African countries and other countries in Region 1 and also within the African continent per se with some of the African countries’ proposals not progressing. Moreover, a majority of the African countries opposed global IMT identification in the lower UHF band (470–694 MHz) although most of them have limited broadcasting needs. Having said that, the examination of the interaction between the international spectrum management regime and Africa's international spectrum policy has revealed some elements of restriction. Firstly, the a priori planning concept could be considered as a restriction over any change to the spectrum use in the UHF band. Secondly, it seems that harmonisation within Region 1 is mostly interpreted as the harmonisation of Africa with Europe considering that the current ITU-R three regions system does not reflect in practice regional spectrum use. Thirdly, IMT identification is not necessary for Africa, which has already the potential to act alone independently of the other Region 1 countries and not necessarily in alignment with the RR. Fourthly, reaching a unified position is quite difficult for the African continent considering the different interests of the African sub-regional groups with large countries influencing such a position. Overall, our main message is that it is not a condition anymore for the African countries to look at the ITU-R for the way to go. [ABSTRACT FROM AUTHOR]

In this article, we give a complete description of the eigenvalues and the corresponding eigenvectors of the distance matrix and the distance signless Laplacian matrix of corona of two graphsand(denoted by), whenis connected transmission regular andis regular. Further, whenis connected transmission regular, we give a complete description of the eigenvalues and the eigenvectors of the distance Laplacian matrix offor any graph. As an application, we find families of distance, distance Laplacian and distance signless Laplacian cospectral nonisomorphic graphs. [ABSTRACT FROM AUTHOR]

A novel method to determine the junction temperature of GaN type blue light LED based on the spectral parameters is proposed. In this method, the relationships among LED junction temperature, centroid wavelength and FWHM are obtained in the lab, and then the junction temperature of operating LED of the same type can be derived from this relationship. A comparative analysis of the junction temperatures which are measured with the centroid wavelength-FWHM method and with the forward voltage method is performed. The standard deviation between these two methods is found to be about 2.3C. Therefore, the combination of centroid wavelength and FWHM can be used to determine the junction temperature of GaN-based blue LED. [ABSTRACT FROM AUTHOR]

Spectrum decision is the capability of Secondary Users to choose the best accessible spectrum band to satisfy a user's Quality of Service (QoS) requirements. Spectrum decision comprises three primary functions; spectrum characterization, spectrum selection and dynamic reconfiguration of cognitive radio. The study of dynamic reconfiguration of transceiver parameters in spectrum decision making has been motivated because of its importance to the realization of efficient spectrum utilization and management in distributed mobile cognitive radio networks. Spectrum decision making in a distributed cognitive radio network is crucial, so as to ensure that an appropriate frequency and channel bandwidth are selected to meet the QoS requirements of different types of applications and to maintain the spectrum quality. In attempting to address the issue of dynamic reconfiguration of transceiver parameters in decision making for cognitive radio networks, different approaches can be found in the literature. However, due to some of the challenges associated with these approaches such as high computational complexity, ambiguity, non-repeatability and non-deplorability of these classical approaches, researchers are still trying to explore other techniques that will be less ambiguous, more efficient, more understandable and easier to deploy in a highly dynamic environment like distributed cognitive radio networks. Hence, this paper reviews the existing approaches, identifies the challenges and proposes a biologically inspired optimal foraging approach to address the decision making problem and other problems relating to the existing approaches. [ABSTRACT FROM AUTHOR]

We study spectral properties of the Neumann–Poincaré operator on planar domains with corners with particular emphasis on existence of continuous spectrum and pure point spectrum. We show that the rate of resonance at continuous spectrum is different from that at eigenvalues, and then derive a method to distinguish continuous spectrum from eigenvalues. We perform computational experiments using the method to see whether continuous spectrum and pure point spectrum appear on domains with corners. For the computations we use a modification of the Nyström method which makes it possible to construct high-order convergent discretizations of the Neumann–Poincaré operator on domains with corners. The results of experiments show that all three possible spectra, absolutely continuous spectrum, singularly continuous spectrum, and pure point spectrum, may appear depending on domains. We also prove rigorously two properties of spectrum which are suggested by numerical experiments: symmetry of spectrum (including continuous spectrum), and existence of eigenvalues on rectangles of high aspect ratio. [ABSTRACT FROM AUTHOR]

The impact of the spectral composition of light on the discoloration of paint pigments has been investigated for the case of lead chromate sulfate, an unstable yellow pigment used by Vincent van Gogh and other painters. With LEDification, museum lighting is moving from using halogen to LED lamps. LED light sources have a significantly different spectral composition than halogen lamps. To understand the impact of these differences on pigment stability, the wavelength dependence of pigment discoloration was determined. Contrary to the expectation that lower wavelength photons induce more damage than higher wavelength ones, UV (394 nm), blue, and cyan light all lead to similar levels of discoloration of a pigment for the same level of radiant power. By understanding this wavelength dependence, it becomes possible to create white light LED lamps with a spectral composition tuned to minimize the degradation effect. An existing LED solution with a modified emission indeed resulted in 30% less color change in the experiment than halogen. Furthermore, a method is proposed to optimize the LED spectra by tuning to the properties of each specific artifact. Simulations show that this can reduce the damage of the light source by 45% in specific cases. [ABSTRACT FROM AUTHOR]

An asymptotic analysis, using the Wave Propagation Method of Keller and Rubinow, was performed on the problem of two identical Timoshenko beams coupled end to end via a so called Type I energy-dissipative joint in 2010. This paper generalizes those results by employing the same method to treat the problem involving any of the four standard types of dissipative joint. A numerical analysis also is performed, and a comparison of the results shows a good match, once one is far enough along the spectrum. In addition, it is found that numerical results for increasing values of the aspect ratio approach the corresponding Euler-Bernoulli beam results, and the asymptotically undamped Timoshenko modes are found to play a lesser role as the aspect ratio increases. [ABSTRACT FROM AUTHOR]