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The focus of the analysis has been to examine pseudo-rapidity distributions obtained for the γ-like particles in pre-shower photon multiplicity detector. Heavy ion collisions with nuclei at relativistic energies are ideal to create an environment with large nuclear and energy densities. Such a situation is quite suitable for the formation of a deconfined state of matter known as hot Quark-Gluon Plasma (QGP) which subsequently cools and expands. In this process the energy density becomes high enough so as a Phase transition Quark-Gluon Plasma (QGP) to hadrons state occurs The results are compared with Simulation analysis using VENUS event generator. In this study an attempt is made to understand phase transition in the domain of conventional statistical Physics according to Ginzburg-Landau Model. [ABSTRACT FROM AUTHOR]

Physics learning achievements are defined as students having the ability to be responsive to global issues and play an active role in providing problem-solving. However, educational design encounters problems linked to creative thinking skills, such as the ability to consider things in new ways to explain physical phenomena that could otherwise be justified. This study uses bibliometric analysis to provide graphical info about the statistical description of the literature from 45 articles issued in reputable international journals correlated to the theme of creative thinking skills in physics from 1959 to 2023. An in-depth study was conducted on 36 articles to reveal the research results. Document Types are obtained from the Scopus database for creative thinking in physics education in articles, book chapters, books, and conference papers. Visualization with Software R Blibiometrix with three visualizations: Annual Scientific Production, most cited articles, Country scientific production, and word cloud and Co-occurrence network. The findings of the analysis show that the dominant topic is creative thinking in physics education of research topics trend in 2023 are students, engineering education, and teaching. Less researched topics are cognitive abilities, active learning, and classical mechanics. Creative thinking in the Physics educational design and to investigate the trend of creative thinking and its authors from across the country. There is about. This study can provide a global roadmap for researchers and education on increasing creative thinking in physics education. [ABSTRACT FROM AUTHOR]

An algorithm for modeling of diffusion, thermal conductivity and viscosity is presented in the paper. Its purpose is demonstration of the transport phenomena in fluids and some basic results in statistical physics in the physics education. The realization of the algorithm as computer program is simple permitting its application by students with only basic knowledge in programming. At the same time the results from the model describe correctly the studied phenomena. [ABSTRACT FROM AUTHOR]

Indonesia has much cultural diversity; one of them is Tari Piring from West Sumatera. Acrobatic movements characterize Tari Piring called Rancak, and it contains many physics concepts such as equilibrium. This research aims to analyze the physics concepts of the center of mass and equilibrium at Tari Piring. Data was collected through literature review and documentation with content analysis techniques consisting of unitizing, sampling, coding, reducing, inferring, and narrating. The center of plate diameter affects the method of plate holding. The resultant force equal zero (∑ F = 0) exist when the dancer creates a body movement opposite to the dancer's hand movement. Also, the torque resultant equals zero (∑ τ = 0) exists when the dancer makes a circular motion of the plate with a constant angular velocity. It's shown that the center of mass and equilibrium concept at Tari Piring can be used as contextual physics learning for meaningful learning. [ABSTRACT FROM AUTHOR]

The calculation of the potential energy surface (PES) for the reaction of cyclopenta[b]naphthalene radical C13H9 with molecular oxygen O2 is presented. It employs modern quantum-chemistry methods, which allows us to find out the most energetically favorable reaction pathways leading to the destruction of five- and six-membered rings in the PAH structure. Computed energy and frequencies values for reactants, intermediates, transition states, and products on the considered PES will be then utilized to calculate the rate constants and product branching ratios for the above-mentioned reaction using up-to-date methods of statistical physics. As a result of the calculations, we predicted the most energetically favorable reaction pathway to lead to the cyclopenta[b]naphthalene-1-one + OH products. [ABSTRACT FROM AUTHOR]

The investigation is made on the phase behavior of the surface-terminating oxygen layer on MXene V2C sheet using the methods of density functional theory (DF)T and statistical physics. Two approximations of the potential of lateral interactions between adsorbed oxygen atoms are constructed. The first approximation is the pair potential form. The second approximation is constructed by the Cluster Expansion (CE) method. As expected, quantitative estimations of approximation errors show that the CE approximation is more accurate, but the pair potential also turns to be of comparable accuracy. Then, adsorption isotherms are calculated using statistical physics algorithms implemented in the SuSMoST code. The isotherms reveal nontrivial phase behavior of the oxygen layer: three phases with coverages of ⅓, ½ and ⅔ monolayer are discovered. From free energy calculations, it is predicted that complete cleaning of the V2C surface from oxygen is possible at temperatures above 2500 K and at partial pressure below 10−9 bar. At atmospheric pressure in air, a complete oxygen coating is stable at temperatures up to 2700 K. Phases with intermediate coverages are stable at temperature below 1200 K and probably could be observed only at ultra-low partial pressure of oxygen. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the lateral interactions of ammonia molecules on the V3C2 surface using the methods of the density functional theory. The calculations were carried out using non-local functionals. We investigated the properties of the adsorption layer MXenes V3C2 methods of statistical physics. The adsorption isotherms were constructed using the SuSMoST program code. They made recalculation of adsorption isotherms from chemical potential to pressure. [ABSTRACT FROM AUTHOR]

In Belarus, women’s representation in the field of natural science, as well as gender imbalance in physics and mathematics, have been investigated using the latest available statistical data, accessed in July 2017. Statistics on daily time use by gender and marital status, with a focus on work and family responsibilities, are provided to aid in pointing out the most challenging issues that are linked to gender-defined roles and affect female career achievements in society. Beneficial strategies to advance women in science are discussed. [ABSTRACT FROM AUTHOR]

Steady structured shock waves in materials including metals, glasses, compounds and solid mixtures, when represented through plots of Hugoniot stress against a measure of the strain rate through which the Hugoniot state is achieved, have consistently demonstrated a dependence to the fourth power. A perhaps deeper observation is that the product of the energy dissipated through the transition to the Hugoniot state and the time duration of the Hugoniot state event exhibits invariance independent of the Hugoniot amplitude. Invariance of the energy-time product and the fourthpower trend are to first order equivalent. Further, constancy of this energy-time product is observed in other dynamic critical state failure events including spall fracture, dynamic compaction and adiabatic shear failure. The present narrative pursues the necessary background describing the foregoing shock physics observations and explores statistical physics principals that may underlie the collective dynamic observations. [ABSTRACT FROM AUTHOR]

This article looks at Skilling's nested sampling from a physical perspective and interprets it as a microcanonical demon algorithm. Using key quantities of statistical physics we investigate the performance of nested sampling on complex systems such as Ising, Potts and protein models. We show that releasing multiple demons helps to smooth the truncated prior and eases sampling from it because the demons keep the particle off the constraint boundary. For continuous systems it is straightforward to extend this approach and formulate a phase space version of nested sampling that benefits from correlated explorations guided by Hamiltonian dynamics. [ABSTRACT FROM AUTHOR]

Colloid-polymer mixtures exhibit a rich phase behavior including reentrance of the liquid-glass transition line, multiple glassy states and glass-glass transition. Such features can be studied in detail via a statistical physics framework in which the colloid-polymer mixture is modelled as an assembly of hard-sphere particles with short-range attraction in a space with large dimensionality. Our analytic approach correctly reproduces the observed phase behavior and holds promise for the exploration of more complex intermolecular potentials [ABSTRACT FROM AUTHOR]

We calculate the normal-mode frequencies and wave amplitudes of the two-dimensional acoustical stadium. We also obtain the statistical properties of the acoustical spectrum and show that they agree with the results given by random matrix theory. Some normal-mode wave amplitudes showing scarring are presented. [ABSTRACT FROM AUTHOR]

The method of maximum entropy has been very successful but there are cases where it has either failed or led to paradoxes that have cast doubt on its general legitimacy. My more optimistic assessment is that such failures and paradoxes provide us with valuable learning opportunities to sharpen our skills in the proper way to deploy entropic methods. The central theme of this paper revolves around the different ways in which constraints are used to capture the information that is relevant to a problem. This leads us to focus on four epistemically different types of constraints. I propose that the failure to recognize the distinctions between them is a prime source of errors. I explicitly discuss two examples. One concerns the dangers involved in replacing expected values with sample averages. The other revolves around misunderstanding ignorance. I discuss the Friedman-Shimony paradox as it is manifested in the three-sided die problem and also in its original thermodynamic formulation. [ABSTRACT FROM AUTHOR]

One of E. T. Jaynes' most important achievements was to derive statistical mechanics from the maximum entropy (MaxEnt) method. I re-examine a relatively new result in statistical mechanics, the Evans-Searles fluctuation theorem, from a MaxEnt perspective. This is done in the belief that interpreting such results in Bayesian terms will lead to new advances in statistical physics. The version of the fluctuation theorem that I will discuss applies to discrete, stochastic systems that begin in a non-equilibrium state and relax toward equilibrium. I will show that for such systems the fluctuation theorem can be seen as a consequence of the fact that the equilibrium distribution must obey the property of detailed balance. Although the principle of detailed balance applies only to equilibrium ensembles, it puts constraints on the form of non-equilibrium trajectories. This will be made clear by taking a novel kind of Bayesian perspective, in which the equilibrium distribution is seen as a prior over the system's set of possible trajectories. Non-equilibrium ensembles are calculated from this prior using Bayes' theorem, with the initial conditions playing the role of the data. I will also comment on the implications of this perspective for the question of how to derive the second law. [ABSTRACT FROM AUTHOR]

In this lecture we give an introduction to theoretical description of strongly correlated materials based on dynamical mean-field theory (DMFT) and its extensions. The goal of this theoretical construction is to retain the many-body aspects of local atomic physics within the extended solid. The effects of short-range non-local correlations within cluster extensions of the DMFT scheme, as well as long-range fluctuations within the fully renormalized dual-fermion perturbation scheme are discussed extensively. Recent progress in the numerical solution of the DMFT effective quantum impurity problem within the recently developed continuous-time Quantum Monte Carlo schemes is reviewed. We then describe realistic extensions of this approach which combine the accuracy of first-principle Density-Functional Theory with the treatment of local many-body effects within DMFT. [ABSTRACT FROM AUTHOR]

Large-eddy simulation (LES) is under its rapid development and is recognized as a possible second generation of CFD methods used in engineering. Spray and coal combustion is widely used in power, transportation, chemical and metallurgical, iron and steel making, aeronautical and astronautical engineering, hence LES of spray and coal two-phase combustion is particularly important for engineering application. LES of two-phase combustion attracts more and more attention; since it can give the detailed instantaneous flow and flame structures and more exact statistical results than those given by the Reynolds averaged modeling (RANS modeling). One of the key problems in LES is to develop sub-grid scale (SGS) models, including SGS stress models and combustion models. Different investigators proposed or adopted various SGS models. In this paper the present author attempts to review the advances in studies on LES of spray and coal combustion, including the studies done by the present author and his colleagues. Different SGS models adopted by different investigators are described, some of their main results are summarized, and finally some research needs are discussed. [ABSTRACT FROM AUTHOR]

Both laboratory tests and discrete numerical simulations related to the drag experienced by various objects inside granular flows showed a large increase in drag coefficient when the Froude number of the undisturbed incident flow decreased. The present paper describes an elementary theory that can catch this observed trend. Accounting for a correlation length related to the presence of the obstacle, it is possible to derive a generalized drag coefficient. The careful calibration of the model on existing data about dry and cohesive dense granular flows around obstacles gives crucial information on the correlation length. [ABSTRACT FROM AUTHOR]

To objectively assess a DEM model for granular flow, the DEM model must be able to randomly sample possible flow histories. Objective assessment is then based on comparing a sample of flows from the model with a sample of experimental flows by means of statistical inference. The practical implementation of this method of model assessment yields a model for the relationships among small collections of macroscopic flow variables. This model of relationships is analogous to models from classical thermodynamics, but is a fully stochastic summarization of bulk flow properties for a physical system that is not at equilibrium. It strongly distinguishes the microscale disorder within the flow from the between-experiment unpredictability of the bulk properties of the flow. It clearly identifies the sources of bulk property uncertainties, and allows ignorance of the detailed dynamics of the flow to be incorporated into the modelling process. This approach to constructing granular thermodynamic models will be compared with approaches to model development arising from modern statistical physics and with the development of the first thermodynamic models. [ABSTRACT FROM AUTHOR]

Highly magnetized, pure electron plasmas confined in a Penning-Malmberg trap allow one to perform experiments on the two-dimensional (2D) fluid dynamics under conditions where non-ideal effects are almost negligible. Recent results on the freely decaying 2D turbulence obtained from experiments with electron plasmas performed in the Penning-Malmberg trap ELTRAP are presented. The analysis has been applied to experimental sequences with different types of initial density distributions. The dynamical properties of the system have been investigated by means of wavelet transforms and Proper Orthogonal Decomposition (POD). The wavelet analysis shows that most of the enstrophy is contained at spatial scales corresponding to the typical size of the persistent vortices in the 2D electron plasma flow. The POD analysis allows one to identify the coherent structures which give the dominant contribution to the plasma evolution. The statistical properties of the turbulence have been investigated by means of Probability Density Functions (PDFs) and structure functions of spatial vorticity increments. The analysis evidences how the shape and evolution of the dominant coherent structures and the intermittency properties of the turbulence strongly depend on the initial conditions for the electron density. [ABSTRACT FROM AUTHOR]

As part of an ongoing project to examine student learning in upper-division courses in thermal and statistical physics, we have examined student reasoning about the approach of macroscopic objects to thermal equilibrium. We have examined reasoning in terms of heat transfer, entropy maximization, and statistical treatments of multiplicity and probability. In the current paper, we present student responses from a set of interviews completed 1-2 years after students had completed the thermal physics course. Students gave a variety of responses, but most students gave answers that did not correspond to the models that they had been taught in the course. [ABSTRACT FROM AUTHOR]

Recent observation for scale invariant neural avalanches in the brain have been discussed in details in the scientific literature. We point out, that these results do not necessarily imply that the properties of the underlying neural dynamics are also scale invariant. The reason for this discrepancy lies in the fact that the sampling statistics of observations and experiments is generically biased by the size of the basins of attraction of the processes to be studied. One has hence to precisely define what one means with statements like 'the brain is critical' . We recapitulate the notion of criticality, as originally introduced in statistical physics for second order phase transitions, turning then to the discussion of critical dynamical systems. We elucidate in detail the difference between a 'critical system', viz a system on the verge of a phase transition, and a 'critical state', viz state with scaleinvariant correlations, stressing the fact that the notion of universality is linked to critical states. We then discuss rigorous results for two classes of critical dynamical systems, the Kauffman net and a vertex routing model, which both have non-critical states. However, an external observer that samples randomly the phase space of these two critical models, would find scale invariance. We denote this phenomenon as 'observational criticality' and discuss its relevance for the response properties of critical dynamical systems. [ABSTRACT FROM AUTHOR]

We describe methods for improving the accuracy of injected particle beams by selectively enhancing the particle statistics in particle-in-cell simulations, using reduced model computations as a guide. We demonstrate convergence of key beam parameters in two dimensions, and show improved noise properties in three dimensions. [ABSTRACT FROM AUTHOR]

We recently proposed a definition of indiscernability in classical mechanics for identical particles prepared in the same manner and without interaction between them [1]. In this paper, we generalize the indiscernability to identical particles in collision. We first consider the elastic collision of pairs of classical particles. We then study the convergence of the quantum indiscernability to the classical indiscernability when the Planck constant h tends to 0. Finally, based on a plausible behavior of the particle during the collision, we propose a possible interpretation of the entanglement phenomenon and of the spin-statistics theorem. [ABSTRACT FROM AUTHOR]

Using 43 months of public gamma-ray data from the Fermi Large Area Telescope, we find in regions close to the Galactic center at energies of 130 GeV a 4.6σ excess that is not inconsistent with a gamma-ray line from dark matter annihilation. When taking into account the look-elsewhere effect, the significance of the observed signature is 3.2σ. If interpreted in terms of dark matter particles annihilating into a photon pair, the observations imply a partial annihilation cross-section of about 10-27 cm3 s-1 and a dark matter mass around 130 GeV. In this talk, we will review aspects of the statistical analysis and comment on possible instrumental indications. [ABSTRACT FROM AUTHOR]

In a recent computational campaign [Ng et al., Astrophys. J. 747, 109, 2012] to investigate a three-dimensional (3D) model of coronal heating using reduced magnetohydrodynamics (RMHD), we have obtained scaling results of heating rate versus Lundquist number based on a series of runs in which random photospheric motions are imposed for hundreds to thousands of Alfvén time in order to obtain converged statistical values. Using this collection of numerical data, we have performed additional statistical analysis related to the formation of current sheets and heating events, or nanoflares [Parker, Astrophys. J. 330, 474, 1988]. While there have been many observations of the energy distribution of solar flares, there have not been many results based on large-scale 3D direct simulations due to obvious numerical difficulties. We will present energy distributions based on our simulations, calculated using a method employed in a 2D study [Dmitruk & Gómez, Astrophys. J., 484, L83, 1997], with power law indices that are consistent with previous studies and observations of solar flare distributions. [ABSTRACT FROM AUTHOR]

An indirect method referred to as the γ-ray strength function method has been devised to determine radiative neutron capture cross sections for unstable nuclei along the valley of β-stability. This method is based on the γ-ray strength function which interconnects radiative neutron capture and photoneutron emission within the statistical model. The method was applied to several unstable nuclei such as 93,95Zr, 107Pd, and 121,123Sn. This method offers a versatile application extended to unstable nuclei far from the stability when combined with Coulomb dissociation experiments at RIKEN-RIBF and GSI. [ABSTRACT FROM AUTHOR]

The internal wave is one of the primary causes for ocean variations in shallow water. The temporal-spatial stability of the sound channel may degrade in the presence of the internal wave. The statistical characteristics of the acoustic field, excited by a 400-Hz source in the ASIAEX 2001 South China Sea (SCS) experiment, are presented. The receiving array was at a distance of 31 km from the source. Time series data of signal intensity were obtained at individual hydrophones of a 16-element vertical line array, and temporal correlations were observed from May 2nd to May 17th. The temporal correlation scales are closely related to the internal wave properties. Strong internal waves, especially solitary wave packets (dnoidal internal waves, cnoidal internal waves, etc.), are principal contributors to the reduction of the temporal correlation scales. The signal temporal correlation length is simulated at different frequencies by using the oceanic data collected in ASIAEX 2001, especially its dependence on the amplitude, nonlinear coefficient, the dispersion coefficient, and the linear speed of the solition. It is found that the temporal correlation length is -1.1 power dependent on the signal frequency and -1.3 power dependent on the amplitude. It is also found that the temporal correlation length decreases with increasing nonlinear coefficient and linear speed, and decreasing dispersion coefficient. The relations between the parameters of the internal wave and the temporal correlation length obtained from the simulations are in agreement with the experimental observations. [ABSTRACT FROM AUTHOR]

We examine a spatially flat Friedmann-Robertson-Walker (FRW) universe filled with interacting dark matter and a modified holographic Ricci dark energy (MHRDE). The interaction term is selected as a significant rational function of the total energy density and its first derivative homogeneous of degree. We show that the effective one-fluid obeys the equation of state of a relaxed Chaplygin gas, then the universe turns to be dominated by pressureless dark matter at early times and undergoes an accelerated expansion in the far future driven by a strong negative pressure. Performing a X2-statistical analysis with the observational Hubble data and the Union2 compilation of SNe Ia, we place some constraints on cosmological parameters analyzing the feasibleness of the modified holographic Ricci ansatz. It turned that MHRDE gets the accelerated expansion faster than the ΛCDM model. Finally, a new model with a component that does not exchange energy with the interacting dark sector is presented for studying bounds on the dark energy at early times. [ABSTRACT FROM AUTHOR]

We investigate a spatially flat Friedmann-Robertson-Walker (FRW) cosmological model with cold dark matter coupled to a modified holographic Ricci dark energy through a general interaction term linear in the energy densities of dark matter and dark energy, the total energy density and its derivative1. Using the statistical method of X2-function for the Hubble data, we obtain H0 = 73.6km/sMpc, ωs = -0.842 for the asymptotic equation of state and zacc = 0.89. The estimated values of Ωc0 which fulfill the current observational bounds corresponds to a dark energy density varying in the range 0.25R < ρx < 0.27R. [ABSTRACT FROM AUTHOR]

A second-order approach to first-order theories is addressed. [ABSTRACT FROM AUTHOR]

We study the QCD deconfinement phase transition from a hadronic gas to a Quark-Gluon Plasma, in the presence of massive particles. Especially, the influence of some parameters as the finite volume, finite mass, flavors number Nf on the transition point and on the order of the transition is investigated. [ABSTRACT FROM AUTHOR]

Equipartition of energy theorem does not explain whether all or only partial gas particles change their mode when the transition temperature achieved. Using a single diatomic molecule, the transition motion between translation mode and translation-vibration mode is observed. The vibration occurs only in a short time during the collision. When the collisions between particles are so frequent then it can be considered that the vibration mode is occurred. A model based on the simulation results and statistical physics theory is proposed to explain the step-by-step transition between translation mode and translation-vibration mode. [ABSTRACT FROM AUTHOR]

Jaynes' Maximum Entropy (MaxEnt) inference starts with the assumption that we have a set of known constraints over the distribution. In statistical physics, we have a good intuition about the conserved macroscopic variables. It should not be surprising that in a real world applications, we have no idea about which coordinates to use for specifying the state of the system. In other words, we only observe empirical data and we have to take a decision on the constraints from the data. In an effort to circumvent this limitation, we propose a nonparametric quantile based method to extract relevant and significant facts (sufficient statistics) for the maximum entropy exponential model. [ABSTRACT FROM AUTHOR]

In the Entropic Dynamics (ED) framework quantum theory is derived as an application of the method of maximum entropy. The particles have well-defined positions but since they follow non differentiable Brownian trajectories they cannot be assigned an instantaneous momentum. Nevertheless, four different notions of momentum can be usefully introduced. We derive relations among them and the corresponding uncertainty relations. The main conclusion is that in ED momentum is not to be interpreted as an attribute of the particles but as a statistical concept associated to the probability distributions. [ABSTRACT FROM AUTHOR]

In the paper we test robustness of particular dynamic systems in a compact regions of a plane and a weak structural stability of one dynamic system of high order in a compact region of its phase space. The test was carried out based on the fundamental theory of dynamical systems on a plane and based on the conditions for weak structural stability of high order dynamic systems. A numerical algorithm for testing the weak structural stability of high order dynamic systems has been proposed. Based on this algorithm we assess the weak structural stability of one computable general equilibrium model. [ABSTRACT FROM AUTHOR]

Do Positron emission particle tracking (PEPT) has been used to track the motion of a single radioactively labeled tracer particle within a bed of similar particles. In this paper, the effect of the original event fraction on the results precise in two experiments has been reviewed. Results showed that the algorithm can no longer distinguish some corrupt trajectories, in addition to; further iteration reduces the statistical significance of the sample without improving its quality. Results show that the optimum value of trajectories depends on the type of experiment. [ABSTRACT FROM AUTHOR]

The ICRF system for ITER is designed to respect the high voltage breakdown limits. However arcs can still statistically happen and must be quickly detected and suppressed by shutting the RF power down. For the conception of a reliable and efficient detector, the analysis of the mechanism of arcs is necessary to find their unique signature. Numerous systems have been conceived to address the issues of arc detection. VSWR-based detectors, RF noise detectors, sound detectors, optical detectors, S-matrix based detectors. Until now, none of them has succeeded in demonstrating the fulfillment of all requirements and the studies for ITER now follow three directions: improvement of the existing concepts to fix their flaws, development of new theoretically fully compliant detectors (like the GUIDAR) and combination of several detectors to benefit from the advantages of each of them. Together with the physical and engineering challenges, the development of an arc detection system for ITER raises methodological concerns to extrapolate the results from basic experiments and present machines to the ITER scale ICRF system and to conduct a relevant risk analysis. [ABSTRACT FROM AUTHOR]

Some foundational considerations on the peculiar status of the second law as a law of physics are made. Given the atomic nature of matter, whose behaviour is well described by statistical physics, the second law could not hold unconditionally, but only statistically. It is not an absolute law. We argue that this peculiar condition is the main rationale and motivation for pursuing exploratory research to challenge the second law. Recently [D'Abramo, Phys. Lett. A 374 (2010) 1801, and D'Abramo, Physica A 390/3 (2011) 482] the concept of vacuum capacitor spontaneously charged harnessing the heat from a single thermal reservoir at room temperature has been introduced, along with a mathematical description of its functioning and a discussion on the main paradoxical feature that seems to violate the second law of thermodynamics. Here we briefly review these works. We describe the theoretical and practical possibility of exploiting such a thermo-charged capacitor as voltage/current generator: if very weak provisos on the physical characteristics of the capacitor are fulfilled, then a non-zero current should flow across the device, allowing the generation of potentially usable voltage, current and electric power out of a single thermal source at room temperature. Preliminary results show that the power output is tiny but non-zero. [ABSTRACT FROM AUTHOR]

This work aims to identify the different microstructures presented by cast iron, namely, lamellar, vermicular and spheroidal microstructures, through the statistical fluctuation and fractal analyses of backscattered ultrasonic signals. The signals were obtained with a broadband direct contact ultrasonic probe with a central frequency of 5 MHz. The statistical fluctuations of the ultrasonic signals were analyzed using Hurst and detrended-fluctuation analyses (DFA), and the fractal analyses were carried out by applying the minimal cover and box-counting techniques to the signals. The curves obtained for the statistical fluctuations and fractal analyses, as function of time window, were processed by using two pattern classification techniques, namely, principal-component analysis (PCA) and Karhunen-Loève expansion. For the Karhunen-Loève expansion, an approximately 100% success rate has been reached for the classification of the different microstructures, for the training and the testing sets of events. The results presented correspond to an average taken over a 100 randomly chosen sets of events. It is concluded that the statistical fluctuation and fractal analyses are effective additional tools for recognition of the different cast iron microstructures. [ABSTRACT FROM AUTHOR]

The probability of detection (POD) of inspection techniques is a key input to estimating the lives of structural components such as aircraft engines. This paper describes work conducted as a part of the development of POD curves for the ultrasonic detection of synthetic hard alpha (SHA) inclusions in titanium aircraft engine forgings. The sample upon which the POD curves are to be based contains four types of right circular SHAs that have been embedded in a representative titanium forging, as well as a number of flat bottomed holes (FBHs). The SHAs were of two sizes, [sharp/mesh/hash_synonym]3 and [sharp/mesh/hash_synonym]5, with each size including seeds with nominal nitrogen concentrations of both 3 and 17 wt. %. The FBHs included sizes of [sharp/mesh/hash_synonym]1, [sharp/mesh/hash_synonym]3, and [sharp/mesh/hash_synonym]5. This discreteness of the data poses a number of challenges to standard processes for determining POD. For example, at each concentration of nitrogen, there are only two sizes, with 10 inspection opportunities each. Fully empirical, standard methodologies such as a versus a provide less than an ideal framework for such an analysis. For example, there is no way to describe the beam limiting effect whereby the signal no longer increases the flaw grows larger than the beam, one can only determine POD at the two concentration levels present in the block, and confidence bounds tend to be broad because of the limited data available for each case. In this paper, we will describe strategies involving the use of physics-based models to overcome these difficulties by allowing the data from all reflectors to be analyzed by a single statistical model. Included will be a discussion of the development of the physics-based model, its comparison to the experimental data (obtained at multiple sites with multiple operators) and its implications regarding the statistical analysis, whose details will be given in a separate article by Li et al. in this volume. [ABSTRACT FROM AUTHOR]

Statistical BGK/DSMC and continuum N-S simulations of a typical vehicle reentry flow were performed taking into account local flow features. The local surface features were known to cause problems during the Apollo era Earth atmosphere reentry Ref. [1] and therefore require close attention as the shapes and design details of the new reentry vehicles tend to build on the Apollo reentry capsules. The TPS thermal response to the high energy reentry flow in cracks and compression pad areas is important to understand to predict the TPS degradation due to the chemical and thermal ablation. The TPS study presented in this article includes the stagnation area micro crack and compression pads which disturb the flow and cause local augmentation of heat flux, which in turn, results in higher recession rates. [ABSTRACT FROM AUTHOR]

We study a thermal boundary condition which is robust and applicable to a wall along which temperature varies. A framework to derive robust thermal boundary conditions using the Maxwell-Boltzmann statistics is proposed for the purpose of the thermal boundary condition of the discrete kinetic theory. The thermal exchange between fluid particles and walls is achieved by using the relation between the velocity change rate and temperature so that we can control the velocity change rate according to a given temperature boundary condition. We simulated microchannel flows by the lattice gas cellular automata and the direct simulation of Monte Carlo. [ABSTRACT FROM AUTHOR]

Understanding martensitic phase transformation (MPT) is of crucial importance for many engineering applications. Especially in polycrystalline shape memory alloys and steels one can observe phase transformations on several length and time scales. Those are firstly the atomistic length scale (nano scale, nm) and the scale of the crystallites (micro scale, μm), which, in turn, have a certain size and orientation distribution. The transformation kinetics is described on the mesoscale (mm), where an averaging of physical properties is useful and possible within the representative volume element (RVE). A proper handling of the relevant physical properties within the RVE allows to incorporate effective material laws for computations on the macroscale (m). The present study focuses mainly on the aspect of deriving the relevant physical properties on the mesoscale from atomistic and single crystal properties, i.e., on closing the gap in modelling MPT between the nano- and microscale resp., and the macroscale. It is shown that no assumptions of kinetic laws of internal variables are necessary, these laws can rather be derived by ab initio calculations using the concepts from statistical physics. [ABSTRACT FROM AUTHOR]

In the present article, we discuss two types of uncertainty relations in Quantum Mechanics-multiplicative and additive inequalities for two canonical observables. The multiplicative uncertainty relation was discovered by Heisenberg. Few years later (1930) Erwin Schrödinger has generalized and made it more precise than the original. The additive uncertainty relation is based on the three independent statistical moments in Quantum Mechanics-Cov(q,p), Var(q) and Var(p). We discuss the existing symmetry of both types of relations and applicability of the additive form for the estimation of the total error. [ABSTRACT FROM AUTHOR]