Miracle-dz/UniFAR-FTUs huggingface dataset:
Eye diagram evaluation of WDM DPSK fiber optical system in presence of PMD, PDL, and CD

An analytic model is reported to evaluate the electric output signals and their variance (Eye Diagram) for multi channel high-speed DPSK fiber optical system in presence of polarization mode dispersion (PMD), polarization dependent loss (PDL) and chromatic dispersion (CD). It is also found that even under linear cross talks, the balanced receiver output show a strong asymmetric phenomenon if adjacent channels are non synchronous.
Reflections on speckle: old and new results

Speckle was re-discovered after the invention of the laser in 1960. The unpublished 1963 Stanford Electronics Laboratory report by J W Goodman was the first comprehensive derivation of the first and second order statistics of the speckle intensity. This short paper describes how the senior author came to know Professor Goodman through their mutual, and lasting, interest in laser speckle. New results in speckle continue to be discovered, and we briefly describe one of these, the elimination of phase vortices using cascade adaptive optics systems.
Evolution without evolution: Dynamics described by stationary observables

Because the time parameter in the Schrodinger equation is not observable, energy apparently obeys a superselection rule in the same sense that charge does. That is, observables must all commute with the Hamiltonian and hence be stationary. This means that it is consistent with all observations to assume that any closed system such as the Universe is in a stationary state. We show how the observed dynamic evolution of a system can be described entirely in terms of stationary observables as a dependence upon internal clock readings.
Effects of turbulence on magnetic reconnection: 3D numerical simulations

Abstract Turbulent reconnection is studied by means of three dimensional (3D) compressible magnetohydrodynamical numerical calculations. The process of homogeneous turbulence is set up by adding three-dimensional solenoidal random forcing implemented in the spectral space at small wave numbers with no correlation between velocity and forcing. We apply the initial Harris current sheet configuration together with a density profile calculated from the numerical equilibrium of magnetic and gas pressures. We assume that there is no external driving of the reconnection. The reconnection develops as a result of the initial vector potential perturbation. We use open boundary conditions. Our main goal is to find the dependencies of reconnection rate on different properties of turbulence. The results of our simulations show that turbulence significantly affects the topology of magnetic field near the diffusion region. We present that the reconnection speed does not depend on the Reynolds numbers as well the magnetic diffusion. In addition, a fragmentation of current sheet decreases the disparity in inflow/outflow ratios. When we apply the large scale and more powerful turbulence the reconnection is faster.
Encoding Custom Instruction Generation as Satisfiability Problem

The emergence of Application-specific Instruction-set Processor (ASIP) has encouraged the proliferation of tool-chains used to streamline its design flow. One of the features much sought-after in these tool-chains is notably the automatic generation of Application-specific Functional Units (AFUs) which, in turn, involves the custom instruction generation as a crucial step. Whereupon an additional step is assumed to pipeline the patterns identified for fulfilling the I/O constraint, custom instructions that correspond to maximal valid subgraphs are mostly beneficial to the speedup gain. Therefore, we present in this paper a propositional satisfiability approach to efficiently identify the custom instructions which contain a large number of valid nodes. Our approach is different substantially from the previous works where it uses an edge classification method to reduce the search space for convexity checking. The experiment results show that our method can, in a matter of few seconds, identify a set of custom instructions that speed up the application to a few times faster.
Second harmonic generation quantitative measurements on collagen fibrils through correlation to electron microscopy

Type I collagen is a major structural protein in mammals that shows highly structured macromolecular organizations specific to each tissue. This biopolymer is synthesized as triple helices, which self-assemble into fibrils (Ø =10-300 nm) and further form various 3D organization. In recent years, Second Harmonic Generation (SHG) microscopy has emerged as a powerful technique to probe in situ the fibrillar collagenous network within tissues. However, this optical technique cannot resolve most of the fibrils and is a coherent process, which has impeded quantitative measurements of the fibril diameter so far. In this study, we correlated SHG microscopy with Transmission Electron Microscopy to determine the sensitivity of SHG microscopy and to calibrate SHG signals as a function of the fibril diameter in reconstructed collagen gels. To that end, we synthetized isolated fibrils with various diameters and successfully imaged the very same fibrils with both techniques, down to 30 nm diameter. We observed that SHG signals scaled as the fourth power of the fibril diameter, as expected from analytical and numerical calculations. This calibration was then applied to diabetic rat cornea in which we successfully recovered the diameter of hyperglycemia-induced fibrils in the Descemet’s membrane without having to resolve them. Finally we derived the first hyperpolarizability from a single collagen triple helix which validates the bottom-up approach used to calculate the non-linear response at the fibrillar scale and denotes a parallel alignment of triple helices within the fibrils. These results represent a major step towards quantitative SHG imaging of nm-sized collagen fibrils.
Nondestructive three-dimensional elemental microanalysis by combined helical x-ray microtomographies

A nondestructive x-ray technique combining simultaneous transmission, fluorescence, and Compton microtomography has been developed. Simultaneous three-dimensional structural information and three-dimensional internal elemental composition maps down to trace concentration levels have been obtained by a helical scan of the sample through an x-ray microbeam. With this method quantitative three-dimensional chemical distributions can be obtained at (sub)micrometric resolution in a nondestructive and noninvasive way, opening unique possibilities for the microanalysis of rare and fragile samples from several research fields.
Single mode Tm and Tm,Ho:LuAG lasers for LIDAR applications

In this paper we report on diode pumped single mode Tm:LuAG and Tm,Ho:LuAG lasers which are developed as master oscillators for an airborne LIDAR system. Using a new fourfold pump setup 51 mW of output power with a Tm(10%):LuAG laser were reached at room temperature. The Tm(10%),Ho(0.4%):LuAG laser proved to be more temperature sensitive than the Tm laser. 18 mW and 30 mW of single mode laser output could be achieved at room temperature and 0°C, respectively. In multi mode laser operation 130 mW output power at room temperature (slope efficiency 36%) were achieved.
Roles of Matrix Metalloproteinase-9 in Cancer Metastasis

Matrix metalloproteinases (MMPs), also called matrixins, function in the extracellular environment of cells and degrade both matrix and non-matrix proteins. They are multidomain proteins and their activities are regulated by tissue inhibitor of metalloproteinases (TIMPs). The uncontrolled regulation of MMPs is involved in various pathologic processes, such as tumor invasion, migration, host immune escape, extravasation, angiogenesis, and tumor growth. Especially, matrix metalloproteinase-9 (MMP-9) is one of the metastasis-accelerating genes involved in metastasis of various types of human cancers. Here, we review the member of MMP family and discusses their domain structure and function, enzyme activation, the mechanism of inhibition by TIMPs. In particular, we focus the role of MMP-9 in relation to cancer metastasis.
The European Capability for Environmental Airborne Gamma Ray Spectrometry

The past few years have seen significant developments in the availability of airborne gamma spectrometry (AGS) systems in Europe, and awareness of their potential contribution in support of off-site emergency management. The high sampling rates, mobility, and fields of view of AGS lead to the possibility of conducting total environmental surveys of areas affected by an accidental release of radioactivity. Recent developments of systems suitable for rapid deployment from fixed- and rotary-wing aircraft, and of rapid data processing and presentation systems, have greatly enhanced the capability of AGS to deliver results on emergency timescales. The need for greater coordination of AGS capabilities and methods at an international level has been recognised in Europe. This presentation summarises the current European capability for AGS, giving brief details of the types of systems available, their mobilisation timescales, calibration status and data produced. The extent to which the systems are currently integrated into emergency preparations, and their possible roles will be discussed. There is a considerable European capability for post-accident deposition mapping using AGS. Further needs in support of emergency response are outlined.
Weak formulation of Biot's equations in cylindrical coordinates with harmonic expansion in the circumferential direction

A weak symmetric form of Biot's equation in cylindrical coordinates with a spatial Fourier expansion in the circumferential direction is presented. The solid phase displacement and the pore pressure are used as the dependent variables. The original three‐dimensional boundary value problem is here, due to the orthogonality of the harmonic functions and the rotationally symmetric geometry, decomposed into independent two‐dimensional problems, one for each harmonic function. This formulation provides a computationally efficient procedure for vibroacoustic finite element modelling of rotationally symmetric three‐dimensional multilayered structures including porous elastic materials. By numerical simulations, this method is compared with, and verified against, full three‐dimensional Cartesian coordinate system finite element models. Copyright © 2009 John Wiley & Sons, Ltd.
Sub-80-fs timing jitter of a stabilized SESAM modelocked VECSEL

We present timing jitter measurements of an actively stabilized SESAM modelocked VECSEL generating 4-ps pulses with 2-GHz repetition rate and 20-mW average output power. The repetition rate was phase-locked to a reference source using a piezo actuator. The timing phase noise power spectral density of the laser output was measured with an Agilent E5052B Signal Source Analyzer. The resulting rms timing jitter integrated over an offset frequency range from 1 Hz to 1 MHz gives a timing jitter of below 80 fs, several times lower than previous modelocked VECSELs and comparable to the noise performance of ion-doped solid-state-lasers.
Tunable helical ribbons

The helix angle, chirality, and radius of helical ribbons are predicted with a comprehensive, three-dimensional analysis that incorporates elasticity, differential geometry, and variational principles. In many biological and engineered systems, ribbon helicity is commonplace and may be driven by surface stress, residual strain, and geometric or elastic mismatch between layers of a laminated composite. Unless coincident with the principle geometric axes of the ribbon, these anisotropies will lead to spontaneous, three-dimensional helical deformations. Analytical, closed-form ribbon shape predictions are validated with table-top experiments. More generally, our approach can be applied to develop materials and systems with tunable helical geometries.
Mobility management scheme for highly dynamic multi-hop wireless networks

In this paper, we consider the mobility management in highly dynamic multi-hop wireless networks (HDNet) used for military communication. We propose a mobility management solution that is the combination of macro mobility management using several HAs and micro mobility management integrating location management with routing. The main advantage of our scheme is that it considerably reduces the location update overhead and especially cares for reliability and survivability. Simulation results show our scheme is suitable for highly dynamic networks.
The dielectric properties of soil‐water mixtures at microwave frequencies

Recent measurements of the dielectric constants of soil-water mixtures have shown the existence of two frequency regions in which the dielectric behavior of these mixtures was quite different. At the frequencies of 1.4–5 GHz there was strong evidence that the variation of the dielectric constant e with water content W depended on soil type. While the real part of e, e′, for sandy soils rose rapidly with the increase in W, e′, for the high clay content soils rose only slowly with W. As a consequence, e′ was generally higher for the sandy soils than for the high clay content soils at a given W. On the other hand, most of the measurements at frequencies < 1 GHz indicated the increase of e with W to be independent of soil types. At a given W, e′ (sandy soil) ≅ e′ (high clay content soil) within the precision of the measurements. These observational features could be satisfactorily interpreted in terms of a simple dielectric relaxation model suggested by Schwarz (1962), with an appropriate choice of the mean relaxation frequency ƒm and the range of the activation energy β. It was found that smaller ƒm and larger β were required for the high clay content soils than for the sandy soils in order to be consistent with the measured data. These requirements on ƒm and β were strongly supported by the observed dependence of the soil surface area per unit weight on the soil types.
The impact of sea-glint upon limb radiance

A simple radiative transfer model is developed to calculate the contribution of sea-glint to limb radiance. It is shown that the absolute sea-glint signal peaks between 70° and 80° solar zenith angle. Sea-glint can contribute 10–15% of the total limb radiance at wavelengths greater than 600 nm, which is several times brighter than an equivalent 5% reflecting Lambertian ocean surface. A test case was identified over the Arabian Sea in October 2002 and the model results compared to limb observations from the Optical Spectrograph and Infra-Red Imaging System (OSIRIS) on-board the Odin satellite. PACS Nos.: 94.10. Gb, 93.85. +q, 42.68. Ay, 42.68. Mj
Fabrication of size-selected Pd nanoclusters using a magnetron plasma sputtering source

We report on the fabrication of palladium (Pd) nanoclusters using a dc magnetron sputtering source. Plasma sputtering vaporizes the target’s material forming nanoclusters by inert gas condensation. The sputtering source produces ionized nanoclusters that enable the study of the nanoclusters’ size distribution using a quadrupole mass filter. In this work, the dependence of Pd nanoclusters’ size distribution on various source parameters, such as the sputtering discharge power, inert gas flow rate, and aggregation length have been investigated. This work demonstrates the ability of tuning the palladium nanoclusters’ size by proper optimization of the source operation conditions. The experimental nanocluster sizes are compared with a theoretical model that reveals the growth of large nanoclusters from “embryos” by a two-body collision. The model is valid for a specific range of deposition parameters (low inert gas flow rates and aggregation lengths equal or below 70 mm).
Optimum Thermal Analysis of a Heat Sink with Various Fin Cross-Sections by Adjusting Fin Length and Cross-Section

A theoretical analysis of a heat sink is presented in this study to pursue the purpose of maximum thermal dissipation and the least material cost. Due to the general derivation, the longitudinal fin arrays on a heat sink can have either square, rectangular, equilaterally triangular, or cylindrical cross-section. By input of the Biot number, Bi, heat transfer coefficient ratio, H, and the shape parameter, γ, the heat transfer equation, which is expressed in implicit form, can be solved by iterative method to calculate the optimum fin length and fin thickness. Meanwhile, the thermal resistance of a heat sink can be obtained to illustrate the cooling performance under various design conditions.
Binomial AR(1) processes: moments, cumulants, and estimation

The modelling and analysis of count-data time series are areas of emerging interest with various applications in practice. We consider the particular case of the binomial AR(1) model, which is well suited for describing binomial counts with a first-order autoregressive serial dependence structure. We derive explicit expressions for the joint (central) moments and cumulants up to order 4. Then, we apply these results for expressing moments and asymptotic distribution of the squared difference estimator as an alternative to the sample autocovariance. We also analyse the asymptotic distribution of the conditional least-squares estimators of the parameters of the binomial AR(1) model. The finite-sample performance of these estimators is investigated in a simulation study, and we apply them to real data about computerized workstations.
Determining optimum pixel size for classification

This work describes a novel method of estimating statistically optimum pixel sizes for classification. Historically more resolution, smaller pixel sizes, are considered better, but having smaller pixels can cause difficulties in classification. If the pixel size is too small, then the variation in pixels belonging to the same class could be very large. This work studies the variance of the pixels for different pixel sizes to try and answer the question of how small, (or how large) can the pixel size be and still have good algorithm performance. Optimum pixel size is defined here as the size when pixels from the same class statistically come from the same distribution. The work first derives ideal results, then compares this to real data. The real hyperspectral data comes from a SOC-700 stand mounted hyperspectral camera. The results compare the theoretical derivations to variances calculated with real data in order to estimate different optimal pixel sizes, and show a good correlation between real and ideal data.
Bias dependence of instability mechanisms in amorphous silicon thin‐film transistors

We have measured the bias dependence of the threshold voltage shift in a series of amorphous silicon‐silicon nitride thin‐film transistors, where the composition of the nitride is varied. There are two distinct instability mechanisms: a slow increase in the density of metastable fast states and charge trapping in slow states. State creation dominates at low fields and charge trapping dominates at higher fields. The state creation is found to be independent of the nitride composition, whereas the charge trapping depends strongly on the nitride composition. This is taken as good evidence that state creation takes place in the hydrogenated amorphous silicon (a‐Si:H) layer, whereas the charge trapping takes place in the a‐SiN:H. The metastable states are suggested to be Si dangling bonds in the a‐Si:H, and the state creation process similar to the Staebler–Wronski effect. The confirmation of state creation in a thin‐film transistor means that states can be created simply by populating conduction‐band states i.
A Solar Radiation Model for Use in Climate Studies

Abstract A solar radiation routine has been developed for use in climate studies. It includes the absorption and scattering due to ozone, water vapor, oxygen, carbon dioxide, clouds, and aerosols. Rayleigh scattering is also included. The UV and visible region (λ 0.69 μm), the broadband parameterization is used to compute the absorption by water vapor in a clear atmosphere, and the k-distribution method is applied to compute fluxes in a scattering atmosphere. The reflectivity and transmissivity of a scattering layer are computed analytically using the delta-four-stream discrete-ordinate approximation. The two-stream adding method is then applied to compute fluxes for a composite of clear and scattering layers. Compared to the results of high spectral resolution and detailed multiple-scattering calculations, .
Ultrahigh-Performance Polycrystalline Silicon Thin-Film Transistors on Excimer-Laser-Processed Pseudo-Single-Crystal Films

Thin-film transistors (TFTs) were fabricated on polycrystalline silicon (poly-Si) films formed by position-controlled large-grain growth technology using an excimer laser. The field-effect mobility, on-off transition slope, and threshold voltage were 914 cm2 V-1 s-1, 93 mV/decade, and 0.58 V for the n-channel device, and 254 cm2 V-1 s-1, 122 mV/decade, and -0.43 V for the p-channel device, respectively. These values indicate that TFTs had an ultrahigh performance comparable to that of {100}-oriented crystal-silicon metal–oxide–semiconductor (MOS) transistors. Furthermore, their effective mobilities had the same effective field and temperature dependences as those of MOS transistors, indicating that electrons and holes were predominantly scattered not by random grain boundaries or defects in the Si film, but by phonons at the SiO2–Si interface, similarly to those of crystal-silicon MOS transistors. These attractive results were obtained as a result of the fact that the TFT channel region was made up of nearly {100}-oriented single grains.
Pressure-driven flow past spheres moving in a circular tube

A computational investigation, supported by a theoretical analysis, is performed to investigate a pressure-driven flow around a line of equispaced spheres moving at a prescribed velocity along the axis of a circular tube. This fundamental study underpins a range of applications including physiological circulation research. A spectral-element formulation in cylindrical coordinates is employed to solve for the incompressible fluid flow past the spheres, and the flows are computed in the reference frame of the translating spheres. Both the volume flow rate relative to the spheres and the forces acting on each sphere are computed for specific sphere-to-tube diameter ratios and sphere spacing ratios. Conditions at which zero axial force on the spheres are identified, and a region of unsteady flow is detected at higher Reynolds numbers (based on tube diameter and sphere velocity). A regular perturbation analysis and the reciprocal theorem are employed to predict flow rate and drag coefficient trends at low Reynolds numbers. Importantly, the zero drag condition is well-described by theory, and states that at this condition, the sphere velocity is proportional to the applied pressure gradient. This result was verified for a range of spacing and diameter ratios. Theoretical approximations agree with computational results for Reynolds numbers up to O(100). The geometry dependence of the zero axial force condition is examined, and for a particular choice of the applied dimensionless pressure gradient, it is found that this condition occurs at increasing Reynolds numbers with increasing diameter ratio, and decreasing Reynolds number with increasing sphere spacing. Three-dimensional simulations and predictions of a Floquet linear stability analysis independently elucidate the bifurcation scenario with increasing Reynolds number for a specific diameter ratio and sphere spacing. The steady axisymmetric flow first experiences a small region of time-dependent non-axisymmetric instability, before undergoing a regular bifurcation to a steady non-axisymmetric state with azimuthal symmetry m = 1. Landau modelling verifies that both the regular non-axisymmetric mode and the axisymmetric Hopf transition occur through a supercritical (non-hysteretic) bifurcation.