Miracle-dz/UniFAR-FTUs huggingface dataset:
Numerical sensitivity in the analysis of a high-dimensional oscillator

We have encountered serious difficulties when we analyze bifurcation phenomena in a high-dimensional oscillator by Lyapunov analysis. Our model uses an eight-dimensional piecewise-linear oscillator containing a hysteresis element. The numerical results show that the solutions do not arrive at a stationary state quite often even if we use piecewise-linear exact solutions and remove more than 100,000 transient iteration of the Poincaré map. Furthermore, we calculate the Lyapunov exponents by averaging 1,000,000 iteration of the Jacobian matrix of the Poincaré map after removing transient 500,000 iteration. The values of the Lyapunov exponents themselves could be trustworthy because piecewise-linear exact solutions have been employed. However, it is very difficult to classify the solutions from the value of the calculated Lyapunov exponents even if the attractor is not chaotic. This is because the bifurcation structure of a higher-dimensional torus is extremely complicated. In some cases, it is very hard to settle how many iteration is necessary to calculate reasonable Lyapunov exponents, and to distinguish whether Lyapunov exponents are exactly zero or not from the values of the numerically calculated Lyapunov exponents. This is a major concern of this study. These complex situations are spotlighted by observing attractors and drawing the graph of the Lyapunov exponents.
The performance of double-clad ytterbium-doped fiber laser with different pumping wavelengths

The effect of pumping wavelengths on the performance of double-clad Ytterbium-doped fiber laser (YDFL) is experimentally demonstrated. The YDFL is constructed using a fiber Bragg grating as wavelength selective filter in a linear cavity resonator. The YDFL operates at wavelength of 1064.4 nm with a bandwidth of 0.2 nm and signal to noise ratio of more than 30 dB. The efficiency of the YDFL is observed to depend on the absorption cross section spectrum of the YDF. The slope efficiencies of the YDFL are obtained at 60.4% and 67.5% for the pumping wavelengths of 937 nm and 967 nm, respectively. The threshold power to achieve lasing is approximately 0.5 W for both pumping wavelengths.
Standing-wave spectrometer

A standing-wave sensor was developed which facilitates the miniaturization of Fourier spectrometers down to the micrometer scale. The spectrometer concept is based on sampling a standing wave by an ultrathin and partially transmissive sensor. The active region of the sensor has a thickness of 30nm–40nm. The standing wave is created in front of a tunable mirror. Varying the position of the mirror results in a phase shift of the standing wave, a modulation of the intensity profile within the ultrathin sensor, and thus, in a modulation of the photocurrent. The spectral information of the incoming light can be determined by the Fourier transform of the sensor signal. The operation principle of the spectrometer is described and the influence of the device design on the spectral resolution of the spectrometer is discussed. Due to the simple linear setup of the sensor and the tunable mirror, the realization of one- and two-dimensional spectrometer arrays is feasible.
Smooth Ternary Subdivision of Triangle Meshes

Standard binary subdivision operators may generate surfaces with unbounded curvatures at points corresponding to ex- traordinary vertices. This defect can be removed by manipulating the eigenvalues of the subdivision operator to impose a bounded curvature spectrum. This procedure may enlarge the support of an extraordi- nary vertex beyond its two-ring. In the ternary subdivision setting, where mesh edges are split 3 to 1, no such enlargement occurs. In this paper, we generalize ternary subdivision of C 2 quartic box splines to arbitrary triangulations. The resulting subdivision algorithm has bounded curvatures and is designed to maintain the convex hull prop- erty.
Smart Pareto filter: obtaining a minimal representation of multiobjective design space

Multiobjective optimization is a powerful tool for resolving conflicting objectives in engineering design and numerous other fields. One general approach to solving multiobjective optimization problems involves generating a set of Pareto optimal solutions, followed by selecting the most attractive solution from this set as the final design. The success of this approach critically depends on the designer's ability to obtain, manage, and interpret the Pareto set—importantly, the size and distribution of the Pareto set. The potentially significant difficulties associated with comparing a significantly large number of Pareto designs can be circumvented when the Pareto set: (i) is adequately small, (ii) represents the complete Pareto frontier, (iii) emphasizes the regions of the Pareto frontier that entail significant tradeoff, and (iv) de-emphasizes the regions corresponding to little tradeoff. We call a Pareto set that possesses these four important and desirable properties a smart Pareto set. Specifically, a smart Pareto set is one that is small and effectively represents the tradeoff properties of the complete Pareto frontier. This article presents a general method to obtain smart Pareto sets for problems of n objectives, given previously generated sets of Pareto solutions. Under the proposed method, the designer uses a smart Pareto filter to control the size of the Pareto set and the degree of tradeoff representation among objectives. Importantly, the smart Pareto filter yields a Pareto set comprising a minimal number of solutions needed to adequately characterize the problem's tradeoff properties. In this article, the smart Pareto filter is analytically developed, and mathematical and physical examples are presented to illustrate the filter's effectiveness.
The evolution of a small inviscid disturbance to a marginally unstable stratified shear flow; stage two

In this paper we examine the evolution of the critical layer in a stratified shear flow when the Richardson number Ri = 1/4. We postulate an initial state consisting of a hyperbolic tangent profile for both velocity and density, together with a disturbance periodic in x. We suggest that, at large values of a non-dimensional time t, all Fourier components of this disturbance but one have died out, and we are concerned with the subsequent development of the remaining one. The magnitude of this component is characterized by a small parameter ϵ, and the next stage of its evolution is forced by the nonlinear terms in a critical layer where the streamwise component of velocity is initially O(t1/2). This stage takes place on a time scale O(ϵ-2/3) when the thickness of the critical layer is O(ϵ2/3). Outside this layer the evolution is linear except in that it is forced by the dynamics of the critical layer, and we find that it has three interesting features. The first is the generation throughout the shear flow of another disturbance of the same wavelength as the original one, but out of phase with it by 1/2π, whose amplitude increases algebraically with time. The second is the appearance of higher harmonics throughout the shear layer, and the third is the occurrence of Stuart-Landau resonance which requires a subtle amendment to the matching procedure.
Gauge invariance in quantum mechanics: zero electromagnetic field

The case of a single charged particle with potential energy is considered when the classical electromagnetic field is zero. The vector and scalar potentials describing this situation are not necessarily zero. When the conventional approach to radiation problems using the interaction A⋅p plus p⋅A plus A2 plus A0 (constants omitted) is used, time‐dependent probabilities are predicted if the vector potential A=−∇Λ≠0 even though the electromagnetic field is zero. The reason for this unphysical behavior is that eigenfunctions of the unperturbed Hamiltonian, which is not gauge invariant, are used to calculate the probability amplitudes. When a manifestly gauge‐invariant procedure is applied to this case the probabilities are constant in all gauges. The reason that physical results are obtained is that eigenstates of the energy operator are used to calculate the probability amplitudes.
Mechanism of negative‐bias temperature instability in polycrystalline‐silicon thin film transistors

It is found that 0.1 V‐order threshold voltage shift (Vth shift) takes place in polycrystalline‐silicon thin film transistors during negative‐bias temperature stress (−BT stress), while the Vth shift in the case of positive‐bias temperature stress is negligibly small. The Vth shift caused by −BT stress has an exponential dependence on the stress gate bias and reciprocal of temperature. Moreover, it also has a close relation with the grain size of poly‐Si films and the hydrogenation process. However, it is independent of the gate insulator materials. Some models previously proposed for amorphous silicon TFTs could not explain these results. A new model is proposed based on a reaction between hydrogen and the SiO2 network at and near the poly‐Si/SiO2 interface to clarify the mechanism and for consistent interpretation of the experimental results. Furthermore, the model has been verified qualitatively.
Propriétés arithmétiques et dynamiques du fractal de Rauzy

Here we construct explicitly two metrical isomorphisms everywhere continuous. One between the symbolic dynamical system associated to the substitution 03C3 : 0 ~ 01, 1 ~ 02, 2 ~ 0 and a rotation of the torus T2; the other is between the adic stationary system associated to the matrix of the substitution and the same rotation. For this we study the arithmetical properties of the boundary of a compact subset of C namely the "Rauzy fractal" . The constructions are generalised to substitutions 03C3k : 0 ~ 01, 1 ~ 02, k ~ 0 où k &#x3E;2.
Meandered multiband metamaterial square microstrip patch antenna design

Magnetic properties can be imparted to a naturally nonmagnetic material by metallic inclusions. A multiband meandered square microstrip patch antenna loaded with such a metamaterial is reported. Metamaterials exhibit qualitatively new electromagnetic response functions that cannot be found in nature. The inclusion of these structures allows simultaneous operation over several frequencies. The antenna was designed to function in multiple bands in the frequency range 0.6–2.2 GHz. The antenna has eight working frequency bands and its centre frequencies are 670 MHz, 1185 MHz, 1293 MHz, 1747 MHz, 1909 MHz, 1999 MHz, 2063 MHz and 2134 MHz. The metamaterial also enhances the gain of the antenna, which is applicable for several wireless applications. Design results were obtained by a high frequency structure simulator which is used for simulating microwave passive components.
Fibromyalgia in Pregnancy: Neuro-Endocrine Fluctuations Provide Insight into Pathophysiology and Neuromodulation Treatment

Fibromyalgia (FM) is a chronic pain disorder with unclear pathophysiological mechanisms, which leads to challenges in patient management. In addition to pain, the disorder presents with a broad range of symptoms, such as sleep disruption, chronic fatigue, brain fog, depression, muscle stiffness, and migraine. FM has a considerable female prevalence, and it has been shown that symptoms are influenced by the menstrual cycle and periods of significant hormonal and immunological changes. There is increasing evidence that females with FM experience an aggravation of symptoms in pregnancy, particularly during the third trimester and after childbirth. In this perspective paper, we focus on the neuro-endocrine interactions that occur between progesterone, allopregnanolone, and cortisol during pregnancy, and propose that they align with our previously proposed model of FM pathogenesis based on GABAergic “weakening” in a thalamocortical neural loop system. Based on our hypothesis, we introduce the possibility of utilizing transcranial direct current stimulation (tDCS) as a non-invasive treatment potentially capable of exerting sex-specific effects on FM patients.
Microwave Roasting as an Alternative to Convection Roasting: Sensory Analysis and Physical Characterization of Dark Chocolate

Roasting cocoa beans by means of microwave radiations seems to be a potential alternative to convection roasting, but little is known about the impact of this method on the perceived flavor profile of the chocolate. Therefore, this research focused on revealing the flavor perception of chocolate produced with microwave roasted cocoa beans assessed by both a trained panel and chocolate consumers. Samples of 70% dark chocolate produced from cocoa beans microwave roasted at 600 W for 35 min were compared with samples of 70% dark chocolate produced from cocoa beans convectively roasted at 130 °C for 30 min. Non-significant differences (p > 0.05) in the measured physical properties, such as color, hardness, melting, and flow behavior, showed that chocolate produced from microwave roasted cocoa beans can exhibit the same physical qualities as convection roasted chocolate. Moreover, combined discriminative triangle tests, with 27 judgements in total, performed by a trained panel, showed that each type of chocolate exhibited distinctive characteristics (d’-value = 1.62). Regarding the perceived flavor, “cocoa aroma” was cited as significantly higher for the chocolate produced from microwave roasted cocoa beans (n = 112) compared to chocolate produced from convection roasted cocoa beans (n = 100) by consumers. Both preference and willingness to buy were higher, though insignificant at a 5% level, for the microwave roasted chocolate. A final potential benefit (studied in this research) of microwave roasting cocoa beans is the reduced energy consumption, which was estimated at 75%. Taking all these results together, the microwave roasting of cocoa is shown to be a promising alternative to convection roasting.
Review of Wireless Charging Technology For Electric Vehicle

A Wireless charging using Wireless Power Transfer (WPT) technique is the future of Electric Vehicles (EVs) mobility. With the implementation of wireless charging, effort of plugging-in the charging cable to the vehicle will be reduced which is the most convenient way of EV charging for human being. WPT system basically works on the principle of electromagnetic induction. WPT has basic two types, inductive power transfer (IPT) and magnetic resonance coupling (MRC) power transfer. Performance efficiency of MRC is improved compared to IPT with the use of resonance network for maximizing power transfer. This resonance networks has to operated in the range of 80kHz-90khz frequency. SAE J2954 standard has been evolving to motivate the development and implementation of wireless charger across the globe. Standard specifies WPT power classes and different Z-gap range of operation for wireless charger. Interoperability Class-I wireless charger will work over the full VA coil ground clearance range and input power range while Class-II will work for specific Z-gap range. Foreign object detection (FOD) and Living object protection (LOP) are one of the major factors need to be considered during the design and development of wireless charger.
Variable wavelength-spacing tunable filter using polarization differential delay line

A tunable filter that can be applied for dispersion compensation, a multiwavelength laser source, or a channel transmitter/attenuator is proposed. Channel spacing and dis- persion can be controlled simultaneously by using a motor- ized polarization differential delay line and a variable coupler in the loop mirror. Due to its periodic characteristic, chro- matic dispersion of multiple channels can be compensated all at once. © 2005 Society of Photo-Optical Instrumentation Engineers.
Astrometry from mutual events of Jovian satellites in 1997

Astrometric results of observations of the mutual events of the Galilean satellites of Jupiter of the PHEMU97 campaign by the Institut de Mecanique Celeste et de Calcul des Ephemerides are presented. These astrometric positions can be directly utilized in the construction of future ephemerides. We attempt here to compare the residuals of the relative astrometric positions of satellites with respect to the E3, G5, E5 and L1 ephemerides. The model to fit the observed light curves includes the intensity variations on the surface of satellites using the mosaics constructed by the teams at the US Geological Survey from Voyager and Galileo imagery.
Changes in the Mechanical Properties of Fast and Slow Skeletal Muscle after 7 and 21 Days of Restricted Activity in Rats

Disuse muscle atrophy is usually accompanied by changes in skeletal muscle structure, signaling, and contractile potential. Different models of muscle unloading can provide valuable information, but the protocols of experiments with complete immobilization are not physiologically representative of a sedentary lifestyle, which is highly prevalent among humans now. In the current study, we investigated the potential effects of restricted activity on the mechanical characteristics of rat postural (soleus) and locomotor (extensor digitorum longus, EDL) muscles. The restricted-activity rats were kept in small Plexiglas cages (17.0 × 9.6 × 13.0 cm) for 7 and 21 days. After this, soleus and EDL muscles were collected for ex vivo mechanical measurements and biochemical analysis. We demonstrated that while a 21-day movement restriction affected the weight of both muscles, in soleus muscle we observed a greater decrease. The maximum isometric force and passive tension in both muscles also significantly changed after 21 days of movement restriction, along with a decrease in the level of collagen 1 and 3 mRNA expression. Furthermore, the collagen content itself changed only in soleus after 7 and 21 days of movement restriction. With regard to cytoskeletal proteins, in our experiment we observed a significant decrease in telethonin in soleus, and a similar decrease in desmin and telethonin in EDL. We also observed a shift towards fast-type myosin heavy chain expression in soleus, but not in EDL. In summary, in this study we showed that movement restriction leads to profound specific changes in the mechanical properties of fast and slow skeletal muscles. Future studies may include evaluation of signaling mechanisms regulating the synthesis, degradation, and mRNA expression of the extracellular matrix and scaffold proteins of myofibers.
Resonant tunneling between parallel, two‐dimensional electron gases: A new approach to device fabrication using in situ ion beam lithography and molecular beam epitaxy growth

Using the techniques of in situ focused ion beam lithography and molecular beam epitaxy regrowth high quality, patterned back gate, double quantum well devices have been fabricated. Independent ohmic contacts were made to the two two‐dimensional electron gases (2DEGs) using a ‘‘selective depletion’’ scheme, and using further gates the carrier densities in each well were controlled. Resonant tunneling between the two electron gases was observed as a function of carrier density in each 2DEG, and as a function of the bias applied between the two wells. Extremely large peak‐to‐valley ratios were observed, resulting from removal of unwanted parallel tunneling paths.
On the accuracy of the semi‐geostrophic approximation

The semi‐geostrophic model has been widely used to understand atmospheric flows such as fronts and developing cyclones. However, there have been a number of demonstrations of its lack of accuracy. This paper presents theory and computations to demonstrate that the semi‐geostrophic model is an accurate approximation to the primitive equations either on horizontal scales larger than the Rossby radius of deformation or when the ratio of horizontal to vertical scales is greater than f/N.
Relation of drift velocity to low‐field mobility and high‐field saturation velocity

From an investigation of the behavior of the momentum distribution function of electrons or holes under scattering rate and momentum scaling transformations, a number of interesting results are derived concerning the parameterization of drift‐velocity–vs–electric‐field relations in terms of mobility and saturation velocity. Indeed it is determined that saturation velocity is invariant under scaling of the magnitude of the scattering rates, which alters mobility, while mobility is invariant under scaling of the magnitude of the momentum, which alters saturation velocity. This independence between mobility and saturation velocity is utilized to generalize to interfaces velocity‐field relations valid the the bulk. Using the transformation of drift velocity under both rate and momentum scaling, partial experimental data can be used to predict high‐field saturation velocities. These velocities need not be reduced due to higher scattering rates as much as their low‐field counterparts. Nonzero magnetic fields and nonuniform scaling are also considered.
Adipokines and myokines as indicators of obese phenotypes and their association with the gut microbiome diversity indices

Today, metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) are distinguished. Adipose and muscle tissues can determine the obese phenotype due to adipokine and myokine production. Gut microbial community is also involved in MHO. The study was aimed to reveal the features of adipokine and myokine levels and their association with the gut microbiome alpha diversity in patients with MHO and MUO. A total of 265 subjects were divided into two groups: healthy individuals and obese patients. The latter were divided into two subgroups: patients with MHO and patients with MUO. Body mass index, waist circumference, HOMA-IR, adipokine and myokine levels, gut microbiome taxonomic composition, alpha diversity indices were defined in all the surveyed individuals, lipid and carbohydrate metabolism was also assessed. Significant differences in the adipokine and myokine levels and their association with the gut microbiome diversity indicators were revealed in patients with different obese phenotypes. Patients with MHO and MUO showed significantly lower adiponectin levels (р < 0.05) and significantly higher leptin and asprosin levels (р < 0.05) than healthy individuals. Patients with MUO had lower adiponectin and leptin levels (p < 0.05) than patients with MHO. Significantly higher FGF21 levels were observed in patients with MUO. Large-scale correlation analysis revealed the relationship between the glucose levels and the gut microbiome diversity indices that was missing in patients with MUO. This indicated the loss of the microbiota diversity effects on the blood glucose control in individuals with MUO, as well as different regulatory roles in the gut microbiome‒liver‒muscle/adipose tissue axes of individuals with MHO and MUO played by gut microbiota. The findings show the relationship between the gut microbiome diversity and the obese phenotype.