Miracle-dz/UniFAR-FTUs huggingface dataset:
Iron and Permalloy based magnetic monolithic tunable microwave devices

We fabricated a series of magnetic monolithic tunable microwave notch-filters and phase shifters. In contrast to previous work with molecular beam epitaxy grown metallic ferromagnets, our devices were created by magnetron sputtering. Single crystal GaAs (001) was used as a substrate. Iron and Permalloy were used as magnetic materials in a coplanar waveguide geometry. The transmission characteristics of the filters were observed to depend on substrate quality, film deposition parameters (Argon pressure, growth rate, power, etc.), and grain size. In addition we observed a substantial increase in the resonance frequency for the Fe based notch-filters. This increase in the resonance frequency is due to a growth-induced uniaxial anisotropy field of 40 kA/m in the Fe films. This is an unexpected and important result especially because the observed anisotropy is growth and not field induced. The resonance frequency shifted from 9.3 GHz at zero applied magnetic field to 15 GHz for an applied static magnetic field.
Multichannel quantum defect theory treatment of triplet gerade and ungerade d-symmetry levelsof H2 and its isotopomers

This work presents a systematic multichannel quantum defect theory (MQDT) analysis of the triplet d-symmetry levels of the hydrogen molecule. First, a new compilation of the best available experimental term values for these levels was prepared. Second, R-dependent quantum defect matrices for the 3Πu, 3Πg, and 3Δg states of H2 were obtained from ab initio potential-energy curves and used in an ab initio MQDT calculation of all known triplet d-symmetry rovibronic levels of H2, HD, and D2. For a few of these levels previous ab initio calculations have been reported. The agreement currently obtained is generally significantly better than that in previous work. Finally, the quantum defect matrices are used to calculate the electronic transition moments 3Πu 3Πg, 3Δg as functions of energy and internuclear distance, R, for application in a companion article. PACS Nos: 31.15Ar, 33.20Wr, 34.10+x, 34.80Kw
Sequential formation of subgroups in OB associations

We reconsider the structure and formation of OB association in view of recent radio and infrared observations of the adjacent molecular clouds. As a result of this reexamination, we propose that OB subgroups are formed in a step-by-step process which involves the propagation of ionization (I) and shock (S) fronts through a molecular cloud complex. OB stars formed at the edge of a molecular cloud drive these I-S fronts into the cloud. A layer of dense neutral material accumulates between the I and S fronts and eventually becomes gravitationally unstable. This process is analyzed in detail. Several arguments concerning the temperature and mass of this layer suggest that a new OB subgroup will form. After approximately one-half million years, these stars will emerge from and disrupt the star-forming layer. A new shock will be driven into the remaining molecular cloud and will initiate another cycle of star formation.Several observed properties of OB associations are shown to follow from a sequential star-forming mechanism. These include the spatial separation and systematic differences in age of OB subgroups in a given association, the regularity of subgroup masses, the alignment of subgroups along the galactic plane, and their physical expansion. Detailed observations of ionizationmore » fronts, masers, IR sources, and molecular clouds are also in agreement with this model. Finally, this mechanism provides a means of dissipating a molecular cloud and exposing less massive stars (e.g., T Tauri stars) which may have formed ahead of the shock as part of the original cloud collapsed and fragmented. « less
The structure of brightest cluster members. I: Surface photometry

La photometrie de surface des galaxies elliptiques brillantes dans les cœurs des amas de galaxies, combinee a la photometrie tiree de la litterature, a permis de constituer un echantillon de 261 galaxies elliptiques dans 63 amas dans le domaine des magnitudes −18≤M V ≤−25
Local Stress Measurement in Thin Thermal SiO2 Films on Si Substrates

A novel method for local stress determination in SiO2 has been developed. The method consists in etching of SiO2 in a manner to create an oxide bridge and separating SiO2 from silicon in the bridge area. In this way, released oxide allows strain calculation and determination of compressive stress in the direction of the longitudinal axis of the bridge. Stress calculations limited to an area as small as 4×10−6 in. 2 have been obtained. The limiting factors to the accuracy of stress determination are the use of a bulk quartz modulus of elasticity, and the accuracy of the measurement of bridge deflection. The thinner the SiO2 film, the higher the accuracy of strain determination. Local stress as high as 1.78×1010 dyn/cm2 is detected in 272‐A‐thick film. The compressive stress determined by this method indicates strong thickness dependence in the films below 1500 A; the thinner the thermal oxide, the higher the average composition stress to its Si/SiO2 interface value. The method is particularly useful for th.
Large‐scale character of an atmosphere in rotating radiative‐convective equilibrium

A rotating radiative‐convective equilibrium on a sphere is reached using a global atmospheric model with prescribed globally uniform sea surface temperature and no insolation. In such an equilibrium state, multiple tropical cyclone‐like vortices coexist in the extratropics, moving slowly poleward and westward. Many vortices have a lifetime longer than 2 months and travel from the tropics to the polar regions. The typical spacing of simulated tropical cyclone‐like vortices is comparable to the deformation radius, while the production of available potential energy is at a scale slightly smaller than those vortices. It is hypothesized that the growth of tropical cyclone‐like vortices is driven by the self‐aggregation of convection, while baroclinic instability destabilizes any vortices that grow significantly larger than the deformation radius. A weak Hadley circulation dominates in the deep tropics, and an eastward propagating wave number 1 Kelvin‐like mode having a period of 30–40 days develops at the equator. The weak Hadley circulation is found to emerge from an initially quiescent atmosphere due to poleward momentum transport by the vortices.
A Scalable Methodology for Agile Chip Development with Open-Source Hardware Components : (Invited Paper)

We present a scalable methodology for the agile physical design of tile-based heterogeneous system-on-chip (SoC) architectures that simplifies the reuse and integration of open-source hardware components. The methodology leverages the regularity of the on-chip communication infrastructure, which is based on a multi-plane network-on-chip (NoC), and the modularity of socket interfaces, which connect the tiles to the NoC. Each socket also provides its tile with a set of platform services, including independent clocking and voltage control. As a result, the physical design of each tile can be decoupled from its location in the top-level floorplan of the SoC and the overall SoC design can benefit from a hierarchical timing-closure flow, design reuse and, if necessary, fast respin. With the proposed methodology we completed two SoC tapeouts of increasing complexity, which illustrate its capabilities and the resulting gains in terms of design productivity.
Transport of gas bubbles in capillaries

The pressure drop and wetting film thickness for isolated bubbles and bubble trains moving in circular and square capillaries are computed. An arclength‐angle formulation of a composite lubrication equation allows for the numerical matching of the lubrication solution of the transition region to the static profiles away from the channel wall. This technique is shown to extend the classical matched asymptotic analysis of Bretherton for circular capillaries to higher capillary numbers Ca. More importantly, it allows the study of finite bubbles, which are shown to resemble infinitely long bubbles in film thickness and pressure drop if their lengths exceed the channel width. The numerical study of bubble trains, verified by a matched asymptotic analysis, shows a surprising result that the pressure drop across one member bubble is identical to that of an isolated bubble at low capillary numbers. This analysis of square capillaries neglects azimuthal flow and is only valid for Ca>3.0×10−3. Nevertheless the film.
Constrained Kalman Filter for Nonlinear Structural Identification

It is well known that hysteresis is a principal source of internal energy dissipation in structural systems. One of the widely accepted hysteretic models for structures is a differential model, called the modified Bouc-Wen model. In this paper, a constrained Kalman filter with a global weighted iteration strategy has been used to estimate the parameters in the modified Bouc-Wen model. An actual seismic signal was used to excite a nonlinear structural system described by the modified Bouc-Wen model that has both degradation and pinching characteristics. The convergence results show that, for both clean and noise-corrupted data, this algorithm is effective in estimating all the 11 parameters with satisfactory precision and fast convergence. As this algorithm has modest computing requirements, it should be acceptable as a basic tool for estimating hysteretic parameters in engineering design.
Dynamics of rotating triple systems: statistical escape theory versus numerical simulations

Dynamical evolution of 120 000 equal-mass rotating triple systems is investigated. The system rotation is described by the parameter w = -L 2 0 E 0 /G 2 m 5 0 , where G is the gravitational constant, m 0 is the mass of a body, and L 0 and E 0 are the angular momentum and the total energy of the triple system, respectively. We consider the values of w = 0.005, 0.1, 1, 2, 4 and 6. For each w, 20 000 triple systems are studied. The initial coordinates and velocities of the components are randomly chosen. The initial data are chosen in two different ways: the first one assumes a hierarchical structure initially and the second one does not. The evolution of each triple system is calculated until either the escape of one of the bodies occurs or the time exceeds 1000 mean crossing times of the system. The orbital parameters of the final binary and the escaper are recorded for each run. We compare the results of numerical simulations and predictions of a statistical escape theory. The statistical theory is based on the assumption of ergodicity, that is, the only information on the initial conditions remaining at the time of the escape of the third body is contained in the conserved total energy, total angular momentum and the mass values. The distributions of various quantities are derived from the allowable phase-space volumes. The distribution of binary energy agrees with earlier results by Heggie, with the angular momentum dependence of Mikkola & Valtonen being added. The eccentricities are distributed in general accordance with Monaghan's work, while the triple systems break up like in radioactive decay, as was previously found by Valtonen & Aarseth. The escape directions are preferentially perpendicular to the total angular momentum vector; the more so, the greater the angular momentum. The escape-angle distributions are derived from the statistical theory and are found to be in agreement with the numerical data. The relative orientations and magnitudes of the binary and third-body angular momenta are also explained based on the statistical theory.
A Diagnostic Study of the Flateyri Avalanche Cyclone, 24–26 October 1995, Using Potential Vorticity Inversion

Abstract The evolution of a deep North Atlantic cyclone, which caused devastating avalanches in northwest (NW) Iceland in October 1995, was investigated. As the main tool for this investigation, potential vorticity analysis was used. This allows the quantification and comparison of the roles of different processes that contribute to the cyclone deepening at different stages. Interpretation of potential vorticity inversions and isentropic air trajectories yields the following picture of the cyclone development. The thermal field over the North Atlantic had acquired strong west–east gradients due to a combination of advection of cold air southeastward from a cold cyclonic gyre south of Iceland and advection of warm air northward on the westward flank of a warm anticyclonic ridge over central Europe. A low-level baroclinic wave forming just south of Ireland was rapidly reinforced due to interaction with a descending, high-value, upper-level potential vorticity anomaly and was isentropically advected from the.
Zinc Ion-Based Switch-on Fluorescence-Sensing Probes for the Detection of Tetracycline

Tetracycline (TC) is an antibiotic that has been widely used in the animal husbandry. Thus, TC residues may be found in animal products. Developing simple and sensitive methods for rapid screening of TC in complex samples is of great importance. Herein, we demonstrate a fluorescence-sensing method using Zn2+ as sensing probes for the detection of TC. Although TC can emit fluorescence under the excitation of ultraviolet light, its fluorescence is weak because of dynamic intramolecular rotations, leading to the dissipation of excitation energy. With the addition of Zn2+ prepared in tris(hydroxymethyl)amino-methane (Tris), TC can coordinate with Zn2+ in the Zn2+-Tris conjugates to form Tris-Zn2+-TC complexes. Therefore, the intramolecular motions of TC are restricted to reduce nonradiative decay, resulting in the enhancement of TC fluorescence. Aggregation-induced emission effects also play a role in the enhancement of TC fluorescence. Our results show that the linear dynamic range for the detection of TC is 15–300 nM. Moreover, the limit of detection was ~7 nM. The feasibility of using the developed method for determination of the concentration of TC in a complex chicken broth sample is also demonstrated in this work.
Compressed Sensing Image Reconstruction Based on Improved Particle Swarm Optimization Algorithm

The reconstruction algorithm has a hot research in compressed sensing. Matching pursuit algorithm has a huge computational task, when particle swarm optimization has been put forth to find the best atom, but it due to the easy convergence to local minima, so the paper proposed a algorithm ,which based on improved particle swarm optimization. The algorithm referred above combines K-mean and particle swarm optimization algorithm. The algorithm not only effectively prevents the premature convergence, but also improves the K-mean’s local. These findings indicated that the algorithm overcomes premature convergence of particle swarm optimization, and improves the quality of image reconstruction.
Age-structured predator–prey model with habitat complexity: oscillations and control

In this article, we study a predator–prey interaction in a homogeneously complex habitat where predator takes a fixed time to develop from immature to its mature stage. The age-structure of the predator and its interaction with the prey is framed in a system of delay differential equations. The objective is to study the role of habitat complexity and the maturation delay of the predator on the overall dynamics of the model system. Different interesting dynamical behaviours can be obtained by regulating two key parameters, namely the degree of habitat complexity and the maturation delay. It is observed that the system becomes unstable from its stable condition when the maturation delay crosses some critical value. The periodic solutions bifurcated from the interior equilibrium is found to be supercritical and stable. Synchronization of population fluctuations is, however, possible by increasing the strength of habitat complexity. The predator population goes to extinction and the prey population reaches to its maximum, irrespective of the length of maturation delay, when the habitat complexity crosses some upper critical value. The qualitative dynamical behaviours of the model system are verified with the data of Paramecium aurelia (prey) and Didinium nasutum (predator) interaction.
Owner Identity Verification in the Internet of Connected Vehicles: Zero Trust Based Solution

—On the Internet of Connected Vehicles, a vehicle has to communicate bi-directionally with several devices for establishing a shared network for inter-vehicle and intra-vehicle connectivity. These connection protocols are commonly structured to connect all the individual components with an implicit degree of trust, which is supposed to protect the whole system from unauthorized users. Technologies like Automotive Ethernet tend to increase security by reducing the implicit trust within the local network devices. However, the lack of individual security protocols in vehicle-to-vehicle communication still keeps the possession of vulnerability to hacks, external attacks, and further disruption. This is where Zero Trust Architecture can become a reliable technology for the exchange of information in between vehicles. Zero trust is a security system that means no one is trusted by default and verification is required from anyone or any device willing to get connected to the intra-vehicle network. In this paper, we have scoped the preliminary and most vital step of this system: verifying the owner identity of a vehicle with zero trust manner. Our approach involves recognizing vehicle license plates and utilizing the license information for retrieving the vehicle owner details to establish trust before allowing connection to the network. Our proposed methodology operates with 85% to 99% accuracy on the license recognition part within recognizable distances using PyTesseract OCR. Reliability to the zero trust solution is gained through necessary information retrieved using GET and POST requests to and from the corresponding driving license information databases.
Thickness of shear bands in metallic glasses

A review of measurements and atomistic modeling shows that shear bands in metallic glasses have a characteristic thickness of ∼10nm. Such extreme localization of plastic deformation, within a thicker liquidlike layer implied by fracture-surface morphology, cannot have a thermal origin. By analogy with granular materials, the thickness is linked to the local structural rearrangements required to generate dilatation. This analysis suggests that first-coordination-shell clusters may be significant structural units in metallic glasses.
Speckle Reduction in Medical Ultrasound Imaging based on Visual Perception Model

—Ultrasound imaging technology is one of the most important clinical imaging modalities due to its safety, low cost, in addition to its versatile applications. The main technical problem in this technology is its noisy appearance due to the presence of speckle, which makes reading imaging more difficult. In this study, a new method of speckle reduction in medical ultrasound images is proposed based on adaptive shifting of the contrast sensitivity function of human vision using a bias field map estimated from the original image. The aim of this work is to have an effective image enhancement strategy that reduces speckle while preserving diagnostically useful image features and allowing practical implementation in real-time for medical ultrasound imaging applications. The new method is used to improve the visual perception of image quality of ultrasound images by adding a local brightness bias to the areas with speckle noise. This allows the variations in image pixels due to speckle noise to be better perceived by the human observer because of the visual perception model. The performance of the proposed method is objectively assessed using quantitative image quality metrics and compared to previous methods. Furthermore, given that image quality perception is subjective, the level of added bias is controlled by a single parameter that accommodates the different needs for different users and applications. This method has potential to offer better viewing conditions of ultrasound images, which translates to higher diagnostic accuracy.
Numerical integration of the differential matrix Riccati equation

Two new Bernoulli substitution methods for solving the Riccati differential equation are tested numerically against direct integration of the Riccati equation, the Chandrasekhar algorithm, and the Davison-Maki method on a large set of problems taken from the literature. The first of these new methods was developed for the time-invariant case and uses the matrix analog of completing the square to transform the problem to a bisymmetric Riecati equation whose solution can be given explicitly in terms of a matrix exponential of order n . This method is fast and accurate when the extremal solutions of the associated algebraic Riccati equation are well separated. The second new method was developed as a means of eliminating the instabilities associated with the Davison-Maki algorithm. By using reinitialization at each time step the Davison-Maki algorithm can be recast as a recursion which is over three times faster than the original method and is easily shown to be stable for both time-invariant and time-dependent problems. From the results of our study we conclude that the modified Davison-Maki method gives superior performance except for those problems where the number of observers and controllers is small relative to the number of states in which ease the Chandrasekhar algorithm is better.
Biped robot with triangle configuration

A new biped robot with a triangle configuration is presented and it is a planar closed chain mechanism. The scalability of three sides of the triangle is realized by three actuated prismatic joints. The three vertexes of the triangle are centers of three passive revolute joints coincidently. The biped mechanism for straight walking is proposed and its walking principle and mobility are explained. The static stability and the height and span of one step are analyzed. Kinematic analysis is performed to plan the gaits of walking on an even floor and going upstairs. A prototype is developed and experiments are carried out to validate the straight walking gait. Two additional revolute joints are added to form a modified biped robot which can follow the instruction of turning around. The turning ability is verified by experiments. As a new member of biped robots, its triangle configuration is used to impart geometry knowledge. Because of its high stiffness, some potential applications are on the way.
Magnetic separation utilizing a magnetic susceptibility gradient

A method of magnetic separation utilizing a colloidal suspension of small submicron magnetic particles is described. In a magnetic field gradient, the magnetic susceptibility of a colloidal magnetic fluid is not constant, but changes spatially with the magnetic gradient, since the concentration distribution of the colloidal magnetic particles is determined by the magnetic force and the thermal diffusion. This susceptibility distribution makes possible a method of particle separation in which particles are positioned at equilibrium due to the magnetic susceptibilities of both the material and the fluid. The method presented here makes possible a separation of particles according to their magnetic susceptibilities only, independent of their densities, sizes, and shapes. A colloidal fluid of magnetic submicron particles can be used to change the magnetic susceptibility of a slurry analogously to the method of using a paramagnetic salt solution in magnetic separation systems.
A wave equation in 2+1: Painleve analysis and solutions

In this paper the nonlinear equation mty=(myxx+mxmy)x is thoroughly analysed. The Painleve test is performed yielding a positive result. The Backlund transformations are found and the Darboux-Moutard-Matveev formalism arises in the context of this analysis. The singular manifold method, based upon the Painleve analysis, is proved to be a useful tool for generating solutions. Some interesting explicit expressions for one and two solitons are obtained and analysed in such a way.