Miracle-dz/UniFAR-FTUs huggingface dataset:
The Impact of Axial Piston Machines Mechanical Parts Constraint Conditions on The Thermo-Elastohydrodynamic Lubrication Analysis of The Fluid Film Interfaces

Abstract The authors analyze the lubricating interfaces of axial piston machines considering thermo-elastohydrodynamic (TEHL) lubrication characteristics. The fluid film geometry in these conditions is strongly influenced by the surface elastic deformation of the solid boundaries. The surface elastic deformations derive from the high dynamic pressures developing in the fluid film, necessary to balance the external oscillating loads. Furthermore, elastic deflections of the fluid film develop from the thermal expansion of the solid bodies, caused by the heat generated due to viscous shear of the fluid film. The accurate determination of the solid boundaries elastic deformation is a key element to predict the fluid film geometry and consequently the lubricating interface performance. When solving for the static elastic deformation of a solid body, constraint conditions must be imposed to avoid rigid body motion. Constraint conditions strongly influence the elastic deformation analysis; therefore their definition must reflect and interpret the mechanical body real conditions. In an axial piston machine all the mechanical bodies defining the fluid film geometry are loosely constrained and significant linear displacements and rotations are intentionally allowed. Hence, the definition of proper constraint conditions for the solid bodies is not a trivial problem and advanced constraint conditions must be considered and implemented. In the fully-coupled numerical models of the lubricating interfaces developed by the research group of the authors, finite element analysis is used to determine the mechanical bodies' elastic deformations. The finite element analysis is coupled with finite volume models of the fluid film, to study the impact of the surface elastic deformations on the interfaces behavior. In this paper, the authors present and discuss the implementation of the inertia relief method on the finite element elastic deformation analysis of the main mechanical parts of an axial piston machine. Inertia relief allows simulating unconstrained structures in a static analysis using their inertia to resist the applied loads. Typical applications of this method include modeling an aircraft in flight, a submarine under water or a satellite in space. The impact of this method on the elastic deformation of the fluid film solid boundary surfaces is shown and compared to standard constraint conditions. In addition, the influence of the inertia relief method on the piston/cylinder interface fluid film behavior is discussed, presenting numerical results for a fully-coupled TEHL simulation over one shaft revolution of a special test pump capable of measuring the piston/cylinder axial viscous friction force. The improved accuracy of the piston/cylinder fully-coupled model including inertia relief effect is presented, comparing simulation results with friction force measurements.
Fundamental mode radiation with solid-state lasers

Optical pumping of solid-state lasers induces thermal lensing in the laser crystal. This lansing determines the beam properties in the resonator; the TEM 00 -mode radiation is limited to a small laser rod volume and it depends on the pump power. Especially with pulse-pumped systems, the generation of stable fundamental mode radiation could only be obtained with low efficiency. Laser resonators with optimum TEM 00 mode output were studied considering the thermal lensing. A kind of resonator was found, the radiation of which is insensitive to thermal distortions. The following is determined by parameters g_{1}, g_{2} : \frac{1}{g_{1}}=2g_{2} +^{1} (\frac{a}{b})^{2} + 2\frac{a}{b} , where a and b are distances between rod ends and mirrors, a and b being the distances between the two mirrors and the lens. The predicted beam behavior was verified experimentally with a high repetition rate YAG laser. A high-precision laser drilling machine was constructed with this design. Because of the insensitive properties, reproducible material processing was achieved in industrial use.
Evolutionary Multiobjective Optimisation Through Spatially-Structured Non-Dominated Sorting: A Preliminary Study

Multiobjective evolutionary algorithms (MOEAs) are useful tools capable of searching problems that contain several conflicting criteria. Although MOEAs have been shown to be capable of finding a wide spread of Pareto-optimal solutions for a given problem, they are still hindered by the requirement for significant computation. This paper investigates a new MOEA that incorporates spatial structure into the population. The introduction of space into the algorithm alters the behaviour of the algorithm so that computational complexity increases linearly with population size. In addition, the paper suggests paths that could be taken to improve the algorithm’s ability to successfully converge upon the global Pareto-optimal front of a given problem.
Non-plasmonic hyperthermia: prerequisites for realization and materials

Abstract. In photothermal cancer therapy, gold nanoparticles and silica-gold nanoshells of specific shapes are used in order to generate heat by excitation of plasmons. We have investigated a different mechanism for heating metal nanoparticles: the Joule effect, whereby the energy resonantly absorbed from laser radiation first dissipates in electron processes before being finally converted into lattice vibrations. For this mechanism to exist, the electronic structure of the nanoparticulate material must possess enhanced densities of states at the Fermi energy and within the energy range 1.3 to 1.9 eV above it, i.e., in the transparency window of the biological tissues. Numerical estimations indicate that Fe-, Mo-, and Ta-doped gold, and Fe-doped tantalum are plausible materials for non-plasmonic hyperthermia. No special conditions concerning the shapes or inner structure of nanoparticles are imposed, which is an advantage over existing techniques.
Measurement and evaluation of the interfacial thermal resistance between a metal and a dielectric

We used a sandwiched film structure of dielectric, metal, and dielectric to measure and also to estimate theoretically the metal-dielectric interfacial thermal resistance. In this structure, a metal layer with a thickness of about 10 nm, including chromium, titanium, aluminum, nickel, and platinum, is sandwiched between two SiO2 layers with a thickness of 100 nm prepared by plasma enhanced chemical vapor deposition. The estimates, 10−10–10−9 m2 K W−1, calculated with a continuum two-fluid model are significantly smaller than the measured values, ∼10−8 m2 K W−1. The continuum two-fluid model, according to the phenomena of electron-phonon nonequilibrium near the interface in a metal, cannot explain completely the cause of this metal-dielectric interfacial thermal resistance. From photographs of the transmission electron microscopy cross section, we argue that defects at an interface likely play an important role in the magnitude of the interfacial thermal resistance.
Radio Emission from Galaxies in the Las Campanas Redshift Survey

To increase the redshift range and look-back time over which the radio luminosity function can be measured directly, we identified 1157 galaxies in the Las Campanas Redshift Survey (LCRS) having isophotal (red) magnitudes miso ≤ 18.0 with radio sources brighter than 2.5 mJy beam-1 in the 1.4 GHz NRAO VLA Sky Survey (NVSS). Since the NVSS has 45'' FWHM angular resolution, these radio and optical limits include nearly all LCRS galaxies with 1.4 GHz luminosities L ≥ 1022.4 W Hz-1 at z ≈ 0.05 to L ≥ 1023.6 W Hz-1 at z ≈ 0.2. The mean redshift ⟨z⟩ ≈ 0.14 of the radio-detected galaxies is higher than the mean redshift ⟨z⟩ ≈ 0.10 of the optical sample. This indicates that, statistically, the radio emission was detected from galaxies with the highest optical luminosities. Of the 1157 galaxies, 261 were also identified with far-infrared (FIR) sources in the IRAS Point Source Catalog and Faint Source Catalog. The principal radio energy sources in all identified galaxies were classified as either "starburst" or "AGN" on the basis of their FIR-radio flux ratios, FIR spectral indices, and radio-optical flux ratios. We show that the radio-optical flux ratio can be effectively used to classify the dominant energy source for the radio emission even if FIR fluxes and radio morphological data are not available.
VECSEL subcavity design and optimization for targeted wavelengths

Optically pumped semiconductor (OPS) vertical-external-cavity surface-emitting lasers (VECSELs) offer the first truly high-brightness high power laser sources with serious power scaling potential to multiple kW levels and flexible spectral coverage from IR to mid-IR. Due to the fact that the semiconductor chip (or subcavity) of a VECSEL serves as both the gain medium and a cavity mirror, the design and optimization of the semiconductor subcavity is key to achieve high power operation and consequently high power extraction via pump area scaling. A fundamental microscopic quantum design approach, allowing for calculating the electro-optical properties of QWs such as the optical gain/absorption and carrier recombination rates, is combined with a coupled optical-thermal-carrier analysis scheme to design and optimize VECSEL chips for wavelengths in the IR. We will describe the design and optimization procedure and present simulation results on VECSEL chips at wavelengths of 980 nm, 1178 nm, and 2 μm.
A New Mechanism Relevant to the Formation of Planetesimals in the Solar Nebula

Abstract Current models of the formation of km-sized planetary building blocks, or planetesimals, by collisional accretion require unrealistically low collision velocities or ad hoc assumptions about sticking in order for growth to occur. Collision velocities in the protoplanetary nebula increase with increasing particle size, leading to bouncing and fragmentation of colliding bodies rather than growth. We describe a new and efficient mechanism in planetesimal accretion which leads to net growth in spite of fragmentation, at least for small planetesimals. Our experimental results show that nebular gas flow returns protoplanetary dust grains to a growing planetesimal, resulting in accretion for impact speeds up to at least 10–15 ms−1. This new threshold velocity is three orders of magnitude higher than the threshold velocity for accretion between macroscopic ice spheres and ten times higher than the sticking velocity for micron-sized dust particles.
Experimental and predicted heating distributions for biconics at incidence in air at Mach 10

Heating distributions were measured on a 1.9-percent-scale model of a generic aeroassisted vehicle proposed for missions to a number of planets and for use as a moderate lift-drag ratio Earth orbital transfer vehicle. This vehicle is spherically blunted, 12.84 deg/7 deg biconic with the fore-cone bent upward 7 deg to provide self-trim capability. A straight biconic with the same nose radius and the same half-angles was also tested. The free-stream Reynolds numbers based on model length were equal to about 2 x 10(5) or 9 x 10 (5). The angle of attack, referenced to the aft-cone, was varied from 0 deg to 20 deg. Heating distributions predicted with a parabolized Navier-Stokes (PNS) code are compared with the measurements for the present Reynolds numbers and range of angles of attack. Leeward heating was greatly affected by Reynolds number, with the heating increasing with decreasing Reynolds number for attached flow (low incidence). The opposite was true for separated flow, which occurred when the fore-cone angle of attack exceeded 0.8 times the fore-cone half-angle. Windward heating distributions were predicted to within 10 percent with the PNS code. Leeward heating distributions were predicted qualitatively for both Reynolds numbers, but quantitative agreement was poorer than on the windward side.
Efficiency enhancement in high power backward-wave oscillators

High power microwave (HPM) sources based on the backward-wave oscillator (BWO) have been investigated for the past two decades primarily because of their potential for very high efficiency (15 to 40%) operation. Several different effects have been proposed to explain this high efficiency compared to conventional BWOs. One of the major contributors to the high efficiency of the plasma-filled Pasotron HPM BWO source is the presence of optimally phased end reflections. The Pasotron uses a long-pulse (/spl ges/100 /spl mu/s) plasma-cathode electron-gun and plasma filled slow-wave structure to produce microwave pulses in the range of 1 to 10 MW without the use of externally produced magnetic fields. The efficiency of the Pasotron can be enhanced by up to a factor of two when the device is configured as a standing-wave oscillator in which properly phased reflections from the downstream collector end of the finite length SWS constructively interfere with the fundamental backward-wave modes and improve the coupling of the beam to the circuit. Operation in this configuration increases the efficiency up to 30% but causes the frequency to vary in discrete steps and the output power to change strongly with beam parameters and oscillation frequency.
Analysis of Ordinal Categorical Data

From the combination of knowledge and actions, someone can improve their skill and ability. It will lead them to live and work much better. This is why, the students, workers, or even employers should have reading habit for books. Any book will give certain knowledge to take all benefits. This is what this analysis of ordinal categorical data tells you. It will add more knowledge of you to life and work better. Try it and prove it.
Ion-Implanted B Concentration Profiles in Ge

We evaluated the dependence of ion-implanted B concentration profiles on dose in crystalline Ge substrates (c-Ge) and evaluated B concentration profiles in amorphous Ge (a-Ge) by a Monte Carlo simulation. We showed that channeling is as significant in c-Ge as it is in crystalline Si (c-Si). We found that the concentration profiles in a-Ge and c-Ge can be fitted using a Pearson IV function and a tail function that has additional parameters for expressing the channeling tail, and we established a corresponding database, which enables us to generate ion-implanted profiles at any dose and energy up to the maximum evaluated energy of 80 keV.
Complex resonances in acoustic waveguides

We consider a two-dimensional infinitely long acoustic waveguide formed by two parallel lines containing an arbitrarily shaped obstacle. The existence of trapped modes that are the eigenfunctions of the Laplace operator in the corresponding domain subject to Neumann boundary conditions was proved by Evans, Levitin and Vassiliev (J. Fluid Mech. 261 1994) for obstacles symmetric about the centreline of the waveguide. In our paper we deal with the situation when the obstacle is shifted with respect to the centreline and study the resulting complex resonances, We are particularly interested in those resonances which are perturbations of (real) eigenvalues. We study how an eigenvalue becomes a complex resonance moving from the real axis into the upper half-plane as the obstacle is shifted from its original position. The shift of the eigenvalue along the imaginary axis is predicted theoretically and the result is compared with numerical computations. The total number of resonances lying inside a sequence of expanding circles is also calculated numerically.
Getting the Constraints on Popper's Probability Functions Right

Shown here is that a constraint used by Popper in The Logic of Scientific Discovery (1959) for calculating the absolute probability of a universal quantification, and one introduced by Stalnaker in "Probability and Conditionals" (1970, 70) for calculating the relative probability of a negation, are too weak for the job. The constraint wanted in the first case is in Bendall (1979) and that wanted in the second case is in Popper (1959).
Development of Ultrasonic Time-of-Flight Computed Tomography for Hard Wood with Anisotropic Acoustic Property

The ultrasound computed tomography (CT) method presented in this paper is an improvement of conventional back projection imaging methods for wooden pillars. The sound velocity in wood changes with the direction of the ultrasound propagation path; therefore, the properties of a medium must be considered in the imaging method. We obtained the 36 time-of-flight (TOF) data of tangents on the same circumference for various diameters. We determined an irregular pathway for each diameter, if the sound velocity of the pathway is slower than 92% of the average velocity of 36 pathways. TOF data for 270 paths were measured in total by manual scanning for one CT image. Although a hole of 25 mm diameter and a slit-type (3×33 mm2) hole are not detected by the conventional back projection method, these artificial defects were detected by our method. Two slit-shaped defects were also detected by our method. We found some knots and cracks in the X-ray image in a wood specimen. These knots were detected by our method; however, it was impossible to distinguish the knots and holes from each other using the CT image.
Fiducial inference applied to uncertainty estimation when identical readings are obtained under low instrument resolution

When identical readings are independently obtained under low instrument resolution d, so that a reading x implies an actual value between x − (d/2) and x + (d/2), the method of fiducial inference yields the result that the commonly assumed standard uncertainty applies only to the case where the input standard deviation is known to be very low, ≈ 0.03d or less. The standard uncertainty is the standard deviation of a rectangular distribution whose base is of length d. If there is little knowledge of the input standard deviation, the standard uncertainty is closer to . The standard uncertainty is the standard deviation of a symmetrical (isosceles) triangular distribution whose base is of length d. This latter standard uncertainty increases above as the number of identical independent readings decreases.
Det-extremal cubic bipartite graphs

Let G be a connected k–regular bipartite graph with bipartition V(G) = X ∪ Y and adjacency matrix A. We say G is det-extremal if per (A) = |det(A)|. Det–extremal k–regular bipartite graphs exist only for k = 2 or 3. McCuaig has characterized the det-extremal 3-connected cubic bipartite graphs. We extend McCuaig's result by determining the structure of det-extremal cubic bipartite graphs of connectivity two. We use our results to determine which numbers can occur as orders of det-extremal connected cubic bipartite graphs, thus solving a problem due to H. Gropp. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 50–64, 2003
Derivative analysis of SP anomalies

Numerical second horizontal derivative self-potential (SP) anomalies obtained from SP data using filters of successive window lengths (graticule spacings) can be used to determine the shape and depth of a buried structure. For a fixed window length, the depth is determined using a simple formula for each shape factor. The computed depths are plotted against the shape factors on a graph. All points for a fixed window length are connected by a continuous curve (window curve). The solution for the shape and depth of the buried structure is read at the common intersection of the window curves. The method is applied to theoretical data with and without random noise and tested on a field example from Turkey.
Error Analysis of a Tree Code

De nouvelles methodes numeriques a structure arborescentes ont recemment ete developpees pour resoudre les problemes gravitationnels a N corps: leur temps de calcul est de l'ordre de N logN ou N au lieu de N 2 mais ces methodes approchees ont une precision limitee. Les calculs des erreurs commises sont presentes
Simulated equilibrium shapes of ferroelastic needle domains

A discrete two-dimensional model of a ferroelastic lattice has been employed to study the equilibrium shapes of needle domains at different depths below the surface. We have found that the trajectory of the needle tip follows the theoretically predicted form of a quadratic function. A high-symmetry high-temperature region is identified, extending from the tip of a needle below the surface, and created as a result of elastic interaction between the needle tip and the surface, giving rise to possible unexpected surface topographies. A configuration where the needle tip touches the surface initially, is found to evolve into two kinked domain walls that move away from each other.
Dependence of absorption spectrum and responsivity on the upper state position in quantum well intersubband photodetectors

Analytical results are derived for the intersubband absorption quantum efficiency, which take into account contributions from both bound‐to‐bound state and bound‐to‐continuum state transitions. Including the final state lifetime broadening, the absorption spectrum gradually decreases in peak strength and becomes broader from the pure bound‐to‐bound case to the pure bound‐to‐continuum situation. The physical reason for the divergence in absorption strength when the upper state is in resonance with the top of the barrier and in the absence of broadening is discussed. The detector current responsivity as a function of well width (and hence upper state position) is estimated. Calculated examples are given, covering the crossover region from the bound‐to‐bound case to the bound‐to‐continuum case. Our results compare well with experiments.
How linear is wall-bounded turbulence?

The relevance of Orr's inviscid mechanism to the transient amplification of disturbances in shear flows is explored in the context of bursting in the logarithmic layer of wall-bounded turbulence. The linearized problem for the wall normal velocity is first solved in the limit of small viscosity for a uniform shear and for a channel with turbulent-like profile, and compared with the quasiperiodic bursting of fully turbulent simulations in boxes designed to be minimal for the logarithmic layer. Many properties, such as time and length scales, energy fluxes between components, and inclination angles, agree well between the two systems. However, once advection by the mean flow is subtracted, the directly computed linear component of the turbulent acceleration is found to be a small part of the total. The temporal correlations of the different quantities in turbulent bursts imply that the classical model, in which the wall-normal velocities are generated by the breakdown of the streamwise-velocity streaks, is .