Miracle-dz/UniFAR-FTUs huggingface dataset:
Change Detection of Grid Construction Based on Satellite Remote Sensing Images and Siamese Neural Network

Quality monitoring of grid construction process based on satellite remote sensing method can standardize the quality behavior of all parties involved in the engineering construction and related institutions and evaluate the environmental and safety impacts of the grid engineering. Thus, a Siamese-Neural-Network-based approach using 3-channel remote sensing images was proposed to quickly monitor grid construction changes. This approach can localize the changed buildings with the help of previous and post remote sensing images of the interesting regions, classify the changes into increased buildings and decreased buildings, and output the masks reaching pixel-level positioning accuracy. The proposed method was tested and compared with other methods based on 2-channel. It has higher accuracy and better robustness and is suitable for the above-mentioned scenes of changes in grid construction. Through experimental research, it is proved that the use of multi-temporal high-resolution remote sensing data and deep learning methods can not only monitor the overall construction status and progress of the project in a timely manner, realize the monitoring of large-scale passages or site clearance, but also monitor the construction scope in a timely and effective manner. The dynamic changes of the ecological environment and the review and evaluation of the construction workload.
A study of turbulence under conditions of transient flow in a pipe

A detailed investigation of fully developed transient flow in a pipe has been undertaken using water as the working fluid. Linearly increasing or decreasing excursions of flow rate were imposed between steady initial and final values. A three-beam, two-component laser Doppler anemometer was used to make simultaneous measurements of either axial and radial, or axial and circumferential, components of local velocity. Values of ensemble-averaged mean velocity, root-mean-square velocity fluctuation and turbulent shear stress were found from the measurements. Being the first really detailed study of ramp-type transient turbulent flow, the present investigation has yielded new information and valuable insight into certain fundamental aspects of turbulence dynamics. Some striking features are evident in the response of the turbulence field to the imposed excursions of flow rate. Three different delays have been identified: a delay in the response of turbulence production; a delay in turbulence energy redistribution among its three components; and a delay associated with the propagation of turbulence radially. The last of these is the most pronounced under the conditions of the present study. A dimensionless delay parameter τ+[= √2τUτ0/D] is proposed to describe it. The first response of turbulence is found to occur in the region near the wall where turbulence production peaks. The axial component of turbulence responds earlier than the other two components and builds up faster. The response propagates towards the centre of the pipe through the action of turbulent diffusion at a speed which depends on the Reynolds number at the start of the excursion. In the core region, the three components of turbulence energy respond in a similar manner. Turbulence intensity is reduced in the case of accelerating flow and increased in decelerating flow. This is mainly as a result of the delayed response of turbulence. A dimensionless ramp rate parameter γ[= (dUb/dt) (1/Ub0)(D/Uτ0] is proposed, which determines the extent to which the turbulence energy differs from that of pseudo-steady flow as a result of the delay in the propagation of turbulence.
The Frontogenetical Forcing of Secondary Circulations. Part II: Properties of Q Vectors in Exact Linear Solutions

Abstract An exact solution of the primitive equations (PEs) and the corresponding exact solutions of the alternative balance (AB), geostrophic momentum (GM), and quasigeostrophic (QG) equations are presented. The PE solution illustrates how the temperature and horizontal vorticity fields evolve in a linear horizontal flow with constant deformation and vertical vorticity when the initial temperature field is also linear, as well as how ageostrophic circulations are produced. The other exact solutions show the errors produced by the various approximations and confirm that the AB solution is more accurate than the GM one and that the QG solution is almost always the most inexact. The utility of the Q vector and similar vectors is examined for each solution. The PE solution verifies that in a hyperbolic wind field (i) the isotherms eventually parallel the outflow axis, (ii) the ageostrophic circulation ultimately becomes normal to the outflow axis, (iii) thermal-wind balance becomes established in the directi.
Deep‐level transient spectroscopy: A new method to characterize traps in semiconductors

A new technique, deep‐level transient spectroscopy (DLTS), is introduced. This is a high‐frequency capacitance transient thermal scanning method useful for observing a wide variety of traps in semiconductors. The technique is capable of displaying the spectrum of traps in a crystal as positive and negative peaks on a flat baseline as a function of temperature. It is sensitive, rapid, and easy to analyze. The sign of the peak indicates whether the trap is near the conduction or valence band, the height of the peak is proportional to the trap concentration, and the position, in temperature, of the peak is uniquely determined by the thermal emission properties of the trap. In addition, one can measure the activation energy, concentration profile, and electron‐ and hole‐capture cross sections for each trap. The technique is presented with a simple theoretical analysis for the case of exponential capacitance transients. Various traps in GaAs are used as examples to illustrate certain features of the DLTS technique. Finally, a critical comparison is made with other recent capacitance techniques.
Phase Segregation in a Two-Phase Self-gravitating Gas Mixture

We discuss the stability of a self-gravitating two-phase gas mixture by linear analysis. The mixture is composed of diffuse phase and immersed dense clouds in pressure equilibrium. Earlier we have shown that in a two-phase self-gravitating mixture, two fundamental wave modes are relevant: (1) the gravitationally modified sound mode with the intrinsic Jeans length λJ1 and (2) the modified void (or pattern formation) mode with the Jeans length λJ2. In this paper, we describe the effect of stabilization of perturbations in a two-phase self-gravitating mixture: when the diffuse phase dominates in volume (the volume filling factor α ≃ 1), the pattern formation mode is gravitationally unstable for λ > λcr, while the fast acoustic mode remains gravitationally stable for arbitrary λ; when the dense phase dominates (α ≪ 1), the slow acoustic mode is gravitationally unstable, while the fast pattern formation mode is stable. The stabilization is caused by displacement of the light component by agglomerating dense clouds: gravitationally unstable dense phase displaces light diffuse phase and thus excites in it wave motions. We argue that gravitational instability of the pattern formation mode results in the segregation of phases. The critical length λcr depends on parameters of phases and their volume filling factors and can vary from 8 pc for molecular clouds to 0.1-0.5 kpc for spiral galaxies and protogalaxies. We briefly discuss possible consequences of the stabilization effect for the two-component model of protogalaxies.
Asymptotic properties of rooted 3-connected maps on surfaces

Abstract In this paper we obtain asymptotics for the number of rooted 3-connected maps on an arbitrary surface and use them to prove that almost all rooted 3-connected maps on any fixed surface have large edge-width and large face-width. It then follows from the result of Roberston and Vitray [10] that almost all rooted 3-connected maps on any fixed surface are minimum genus embeddings and their underlying graphs are uniquely embeddable on the surface.
REDUCED FORM OF YANG-MILLS EQUATION OF SU(2) ON R~(3,1)

An explicit expression of a dierential linear transformation is obtained in this letter. The Yang-Mills equation of SU(2) on Euclidean four- dimensional flat sapce becomes a reduced form via this dierential linear trans- formation. And then, some solutions of the Yang-Mills equation could to be obtaind very easily.
ON THE CONNECTION OF SPIN AND COMMUTATION RELATIONS BETWEEN DIFFERENT FIELDS

The connection of spin and commutation relations for different fields is studied. The normal locality is defined as the property that two Boson fields as well as a Boson field and a Fermion field commute, while two Fermion fields anticommute with each other at a spacelike distance. A regular locality is defined as any combination of commutativity and anticommutativity between various pairs of fields at spacelike distance, where the kinematically related fields are assumed to obey the same type of commutation relations. The normal and regular weak locality is defined in a corresponding way. It is proved on the basis of the Lorentz invariance and spectrum conditions that any regular locality is equivalent to the normal locality plus a set of even‐oddness conservation laws. It is further shown, under the assumption of the normal weak locality between pairs of the same field, that any regular weak locality is equivalent to the normal weak locality plus a set of even‐oddness conservation laws.
Nanowire-based ternary transistor by threshold-voltage manipulation

We report on a ternary device consisting of two nanowire channels that have different threshold voltage (Vth) values and show that three current stages can be produced. A microscale laser-beam shot was utilized to selectively anneal the nanowire channel area to be processed, and the amount of Vth shift could be controlled by adjusting the laser wavelength. Microscale laser annealing process could control Vth of the individual nanowire transistors while maintaining the other parameters the constant, such as the subthreshold slope, on–off current ratio, and mobility. This result could provide a potential for highly integrated and high-speed ternary circuits.
Large elastic deformations of isotropic materials IX. The deformation of thin shells

The theory of the large elastic deformation of incompressible isotropic materials is applied to problems involving thin shells. The inflation of a circular diaphragm of such a material is studied in detail. It is found that the manner in which the extension ratios and curvatures vary in the immediate neighbourhood of the pole of the inflated diaphragm can be determined analytically. However, in order to determine their variation throughout the inflated diaphragm a method of numerical integration has to be employed. Although this is, in principle, valid for any form of the stored-energy function, the calculations are carried through only for the Mooney form. Finally, the problem of the inflation of a spherical balloon, which has already been dealt with by Green & Shield (1950), is discussed in further detail.
Arterial cannula shape optimization by means of the rotational firefly algorithm

This article presents global optimization results of arterial cannula shapes by means of the newly modified firefly algorithm. The search for the optimal arterial cannula shape is necessary in order to minimize losses and prepare the flow that leaves the circulatory support system of a ventricle (i.e. blood pump) before it reaches the heart. A modification of the standard firefly algorithm, the so-called rotational firefly algorithm, is introduced. It is shown that the rotational firefly algorithm allows for better exploration of search spaces which results in faster convergence and better solutions in comparison with its standard version. This is particularly pronounced for smaller population sizes. Furthermore, it maintains greater diversity of populations for a longer time. A small population size and a low number of iterations are necessary to keep to a minimum the computational cost of the objective function of the problem, which comes from numerical solution of the nonlinear partial differential equations. Moreover, both versions of the firefly algorithm are compared to the state of the art, namely the differential evolution and covariance matrix adaptation evolution strategies.
Frequency and neighborhood effects on auditory perception of drug names in noise

Drug name confusions occur when drugs whose names look or sound alike (e.g., Celebrex/Cerebyx) are confused by clinicians and patients. Our project examines effects of frequency and similarity on auditory perception of drug names. Luce’s Neighborhood Activation Model is the theoretical framework. Frequency information was taken from national prescribing frequency databases. Spoken drug names were transcribed to ARPAbet. Similarity neighborhoods were calculated based on phoneme edit distance using phoneme‐to‐phoneme confusion probabilities as substitution costs. The confusability of each name was estimated using Luce’s frequency‐weighted neighborhood probability rule (FWNPR). One hundred brand and one hundred generic drug names, stratified by FWNPR, were recorded. Low and high frequency sounds were filtered out to mimic telephone bandwidth. Names were used as stimuli in a perceptual identification experiment. Participants heard the drug names, at three different signal‐to‐noise ratios, against a background.
Enhancement of polycrystalline silicon solar cells using ultrathin films of silicon nanoparticle

Ultrathin films of highly monodispersed luminescent Si nanoparticles are directly integrated on polycrystalline Si solar cells. The authors monitor the open-circuit voltage and the short circuit current. The results demonstrate that films of 1 nm blue luminescent or 2.85 nm red luminescent Si nanoparticles produce large voltage enhancements with improved power performance of 60% in the UV/blue range. In the visible, the enhancements are ∼ 10 % for the red and ∼ 3 % for the blue particles. The results point to a significant role for charge resonant transport across the nanofilm and Schottky-like rectification at nanoparticle-metal interface.
Characteristic electroforming behavior in Pt/TiO2/Pt resistive switching cells depending on atmosphere

Electroforming effects on the composition, structure, and electrical resistance of Pt/TiO2/Pt switching cells are investigated. The correlation between the electroforming procedure and the resulting bipolar switching behavior is discussed. The dependence of electroforming behavior on atmosphere is also identified, from which we define symmetric or asymmetric electroforming. The symmetry of electroforming is a key factor determining the resulting bipolar switching characteristics. From the experimental results we suggest a possible mechanism for electroforming in Pt/TiO2/Pt in terms of the formation of oxygen gas and vacancies in the vicinity of the anode.
A method for the solution of the forward position problems of planar mechanisms with prismatic and revolute joints

Abstract In this paper, a method to solve the forward position problems of planar linkages with prismatic and revolute joints is presented. These linkages can have any number of degrees of freedom. This method has been named the geometrical iterative method and is based on geometrical concepts. An iteration sequence that corresponds to the system of non-linear equations describing closure of the mechanism loops is defined. This sequence is applied in successive iterations to obtain the position of the mechanism. In order to achieve convergence, the iteration sequence must fulfil two fundamental conditions. A searching algorithm has been developed to obtain a useful iteration sequence. It is based on the use of hierarchical rules and criteria. The method has been implemented in a simulation program developed by the authors. Several illustrative examples are presented using representative linkages.
ERROR ESTIMATION AND ADAPTIVITY FOR FINITE-VOLUME METHODS ON UNSTRUCTURED TRIANGULAR MESHES: ELLIPTIC HEAT TRANSFER PROBLEMS

In this article, a simple and reliable a posteriori error estimate methodology for the finite-volume method on triangular meshes and an adaptive mesh refinement procedure are presented. The proposed error estimate employs a high-order approximation for the scalar at the triangles faces. The estimate technique does not demand expressive computational efforts and memory storage. The adaptive procedure is based on the equal distribution of the error over all the triangles, allowing for suitable local mesh refinements. The error is measured by an H 1 norm, and its convergence behavior is evaluated using four elliptic problems for which the analytical solutions are known. The error differences using analytical and estimate solutions are compared for those problems, and good performance of the adaptive procedure is verified.
Plasma nanofabrication and nanomaterials safety

The fast advances in nanotechnology have raised increasing concerns related to the safety of nanomaterials when exposed to humans, animals and the environment. However, despite several years of research, the nanomaterials safety field is still in its infancy owing to the complexities of structural and surface properties of these nanomaterials and organism-specific responses to them. Recently, plasma-based technology has been demonstrated as a versatile and effective way for nanofabrication, yet its health and environment-benign nature has not been widely recognized. Here we address the environmental and occupational health and safety effects of various zero- and one-dimensional nanomaterials and elaborate the advantages of using plasmas as a safe nanofabrication tool. These advantages include but are not limited to the production of substrate-bound nanomaterials, the isolation of humans from harmful nanomaterials, and the effective reforming of toxic and flammable gases. It is concluded that plasma nanofabrication can minimize the hazards in the workplace and represents a safe way for future nanofabrication technologies.
Acceleration of electrons at type II shock fronts and production of shock‐accelerated type III bursts

We present evidence of electron acceleration by type II-burst-emitting shocks in the corona. Some of the electrons travel outward along open magnetic field lines and produce “shock-accelerated type III bursts” (or SA type III bursts) along their paths. The SA type III bursts are evident in dynamic spectra that cover part or all of the range from metric to kilometric wavelengths. The unique feature of our observations is the complete or near-complete frequency coverage from about 2 GHz to < 0.1 MHz, that is, ≲ 1.01 Ro to 1 AU. A sample of eight events is presented. All would be classified as “shock accelerated events” at hectometric wavelengths, as first defined by Cane et al. [1981]. Our complete spectra frequently show several to many type III-like bursts emanating from near the type II burst toward low frequencies, with no trace of emission at frequencies higher than that of the type II burst. The drift rates of these SA type III bursts are similar to those of normal type III bursts, and the exciting electrons have speeds of order 0.1c to 0.2c, or energies of 3–10 keV and higher. Their intensity at hectometer wavelengths is similar to that of normal type III bursts. They often persist to the lowest frequencies observable, near the local plasma frequency at 1 AU. In most of the events examined, there were no microwave bursts from the low corona whose intensity profiles were similar to the hectometric profiles. We therefore conclude that these SA type III bursts originate in type II shocks and are caused by energetic electrons accelerated at the shocks. Of the eight events analyzed, three contain only SA type III bursts. For the remainder, normal type III bursts predominate initially, followed by SA type III bursts later in the event. We emphasize the need for spectra with near-continuous coverage, especially from decametric to kilometric wavelengths, to identify SA type III bursts unambiguously and to distinguish between the contributions of normal and SA type III bursts.
Diophantine Solutions Based Permutation for Image Encryption

A permutation technique based on the resolution of the system of three independent Diophantine equations is presented. Each Diophantine equation parameters are two positive integers generated from a chaotic system. The resulting solutions are then used for rearranging the positions of the bits and pixels in the ciphered sequence. The performance of such a technique is compared to GRP and Xiang permutation algorithms. From this permutation algorithm an efficient chaos-based block cipher using a chaotic logistic map is proposed. Statistical analyses of this system show a high security level and non-propagation of errors.
Substitutional carbon reduction in SiGeC alloys grown by rapid thermal chemical vapor deposition

The substitutional carbon reduction in Si1−x−yGexCy strained layers, annealed at high temperatures, increases the compressive strain in the originally strain-compensated alloys. From the rocking curve simulation, the maximum amount of carbon reduction was below 0.9% for the various samples which were annealed below 1000 °C in the nitrogen flow. The interstitial silicon injection by thermal oxidation of the Si cap on the Si1−x−yGexCy layer enhances the reduction of substitutional carbon to a concentration of 1.3%. Oxidation of Si1−x−yGexCy alloys yields a Ge-enriched Si1−xGex layer with the Ge concentration larger than the initial content, and the formation of 3C silicon carbide precipitate is observed by the Fourier transform infrared spectroscopy.
Robust level set method for computer vision

Level set method provides powerful numerical techniques for analyzing and solving interface evolution problems based on partial differential equations. It is particularly appropriate for image segmentation and other computer vision tasks. However, there exists noise in every image and the noise is the main obstacle to image segmentation. In level set method, the propagation fronts are apt to leak through the gaps at locations of missing or fuzzy boundaries that are caused by noise. The robust level set method proposed in this paper is based on the adaptive Gaussian filter. The fast marching method provides a fast implementation for level set method and the adaptive Gaussian filter can adapt itself to the local characteristics of an image by adjusting its variance. Thus, the different parts of an image can be smoothed in different way according to the degree of noisiness and the type of edges. Experiments results demonstrate that the adaptive Gaussian filter can greatly reduce the noise without distorting the image and made the level set methods more robust and accurate.
The impact of mechanical stress on the degradation of AlGaN/GaN high electron mobility transistors

Coupled electro-thermo-mechanical simulation and Raman thermometry were utilized to analyze the evolution of mechanical stress in AlGaN/GaN high electron mobility transistors (HEMTs). This combined analysis was correlated with electrical step stress tests to determine the influence of mechanical stress on the degradation of actual devices under diverse bias conditions. It was found that the total stress as opposed to one dominant stress component correlated the best with the degradation of the HEMT devices. These results suggest that minimizing the total stress as opposed to the inverse piezoelectric stress in the device is necessary in order to avoid device degradation which can be accomplished through various growth methods.