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Denoising of a cargo-plane jet engine compressor vibration signal is investigated in this article. Discrete wavelet transform and two families of Donoho–Johnston and parameter method thresholding, are applied to vibration signal. Eighty four combinations of wavelet thresholding and mother wavelet are evaluated. A new performance evaluation scheme for optimal selection of mother wavelet and thresholding method combination is proposed in this paper, which is make a trade off between four performance criteria of signal to noise ratio, percentage root mean square difference, Cross-correlation, and mean square error. Dmeyer mother wavelet (dmey) combined with Rigorous SURE thresholding has the maximum trade off value and was selected as the most appropriate combination for denoising of the signal. It was shown that inappropriate combination leads to data losing. Also higher performance of proposed trade off with respect to other criteria was proven graphically.

We consider estimation of a missing value for a stationary autoregressive process of order one with exponential innovations and compare two methods of estimation of the missing value, with respect ...

In this study, the physical, tribological and corrosion properties of Mg matrix nanocomposite reinforcement were investigated by Al2O3 nanoparticles fabricated using the single-action press (SP) and double-action press (DP) at 300, 500, and 700 MPa pressures with different volume percentages (0, 1.5, 3, and 5%) of Al2O3 reinforcement nanoparticles. The samples were sintered in 450 °C argon gas for 2 h. The results showed an increase in the experimental density as well as green density in DP compared to SP. The experimental density of Mg-5 vol% Al2O3 nanocomposite compacted at 700 MPa by DP was achieved to be 3% higher than the experimental density of the same specimen compacted at 700 MPa by SP. Furthermore, the relative density of this sample compacted at 700 MPa by DP was achieved to be 5.5% higher than the relative density of this sample compacted at 300 MPa by SP. The wear rate of the Mg-5 vol% Al2O3 fabricated at 700 MPa by DP was achieved as 14%, 50%, and 35% lower than that of Mg-5 vol% Al2O3 sample fabricated at 700 MPa by SP and the Pure Mg compacted at 700 MPa by SP and DP, respectively. The corrosion test results showed that the corrosion rate increased with increasing the percentage of nanoparticles so that the corrosion rate of the Mg-5 vol% Al2O3 sample was achieved 520% higher than the Pure Mg fabricated at 700 MPa by DP.

In this research, pure powder of Mg was mixed with 0, 1.5, 3, 5%vol. of Aluminium oxide in a planetary mill. Next, the powder mixture was poured in a mold and pressed in two diverse conditions of (1) hot pressing at 600 MPa pressure and 450 °C temperature for 25 min and (2) cold pressing at 600 MPa pressure in the room temperature and samples sintered in a furnace under Argon gas at 450 °C temperature for 2 h. Density and mechanical properties, e.g., microhardness, and wear properties of the produced samples were assessed. Also, metallographic photography and SEM analysis were done on the samples to investigate their microstructure properties and analyze their worn surfaces. The results revealed that with an increase in the volume of the reinforcement particles, the experimental density and microhardness soared, on the contrary, the relative density showed a decreasing trend. Moreover, the results of the microhardness analysis for the produced samples via hot pressing method were achieved better than those of cold pressing, as the highest hardness 81HV was achieved for %5 vol. Al2O3 containing samples produced through the hot pressing method, which was about %18 more than that of the %5 vol. Al2O3 containing samples produced via the cold pressing method and was about %85 more than of the pure Mg samples produced via the hot pressing method. The results of the samples’ wear properties also signified the improvement of wear resistance and decrease of mass loss with an increase in the volume fraction of the reinforcement particles. The lowest mass loss of 2.5 g was obtained for the sample containing %5 vol. of the reinforcement particle which was produced via the hot pressing method. This value was less about %40 and %80 compared to pure Mg samples produced via hot and cold pressing methods, respectively.

Rubber is a type of material widely used in industries for waterproofing, storing and transporting fluids, energy shock dampers, thermal insulation, and corrosion protection. Natural Rubber (NR) polymer is a material that is extensively used in the automotive industries because of its unique properties such as high strength, low weight, and excellent corrosion resistance. In this study, the mechanical properties of NR based car bumpers were investigated by adding reinforcing particles to it. The used reinforcing materials include SiC, MgO, Fe2O3 particles and Glass fibers, which were added to the base material at different sizes and weight percentages including 4% and 8%. Composite samples were made by mixing NR with reinforcement using special rollers and then vulcanized in the furnace at a specific temperature, to achieve standard torque, for each individual sample. To better characterize produced samples and recognizing of elements and their bonds, FT-IR, TGA, and XRD analysis were done. All specimens were subjected to hardness and tensile tests; their axial and radial stiffness, as well as their component durability tests, were investigated and compared with the base material. The maximum results were obtained from the mechanical property tests belonged to the reinforced specimen with 8%w.t. Glass fibers, that the ultimate tensile strength, hardness, and durability were 57%, 32%, and 33% higher than that of the non-reinforced NR sample, respectively. The SEM and SEM-MAP images of the fracture cross-section showed a crack growth inhibition effect in the samples by adding glass fibers.

Mg metal matrix nanocomposites reinforced by 0, 1.5, 3 and 5 vol fractions of TiO2 and ZrO2 nanoparticles were fabricated using hot quasi-static compaction method under the pressure of 600 MPa at 450 °C for 25 min. The density, hardness, ultimate compressive strength (UCS) and coefficient of thermal expansion (CTE) of the samples were experimentally measured. The results indicated that by increasing the volume fraction of nanoparticles, the relative density and CTE were reduced but hardness and UCS were improved. The results also indicated that relative density of Mg-ZrO2 was higher than that of Mg-TiO2. The CTE of the nanocomposites was decreased by 1.1 and 1.4% for the 5 vol % fraction of the TiO2 and ZrO2 reinforcing particles, respectively. The highest hardness was obtained for the Mg-5vol. % ZrO2. UCS of samples was improved by 22% and 10% for the material reinforced by 3 vol % and 5 vol % of ZrO2 and TiO2, respectively.

Objectives We aim to develop a 3D-bilayer collagen (COL) membrane reinforced with nano beta-tricalcium-phosphate (nβ-TCP) particles and to evaluate its bone regeneration in combination with leukocyte-platelet-rich fibrin (L-PRF) in vivo. Background data L-PRF has exhibited promising results as a cell carrier in bone regeneration in a number of clinical studies, however there are some studies that did not confirm the positive results of L-PRF application. Methods Mechanical & physiochemical characteristics of the COL/nβ-TCP membrane (1/2 & 1/4) were tested. Proliferation and osteogenic differentiation of seeded cells on bilayer collagen/nβ-TCP thick membrane was examined. Then, critical-sized calvarial defects in 8 white New Zealand rabbits were filled with either Col, Col/nβ-TCP, Col/nβ-TCP combined with L-PRF membrane, or left empty. New bone formation (NBF) was measured histomorphometrically 4 & 8 weeks postoperatively. Results Compressive modulus increases while porosity decreases with higher β-TCP concentrations. Mechanical properties improve, with 89 % porosity (pore size ∼100 μm) in the bilayer-collagen/nβ-TCP membrane. The bilayer design also enhances the proliferation and ALP activity. In vivo study shows no significant difference among test groups at 4 weeks, but Col/nβ-TCP + L-PRF demonstrates more NBF compared to others (P Conclusion The bilayer-collagen/nβ-TCP thick membrane shows promising physiochemical in vitro results and significant NBF, as ¾ of the defect is filled with lamellar bone when combined with L-PRF membrane.

In order to gain deeper insight into the physics of the novel rotating solution of nonideal transverse magnetohydrodynamics (MHD), presented in one of our recent works, we replace the previously considered Maxwell theory with the $\mathcal{CP}$ violating Maxwell-Chern-Simons (MCS) theory. In this way, dissipationless chiral magnetic (CM) and anomalous Hall (AH) currents appear in the MCS equation of motion, that, together with equations of relativistic hydrodynamics, builds the set of constitutive equations of the nonideal transverse Chern-Simons magnetohydrodynamics (CSMHD). We are, in particular, interested in the effect of these currents on the evolution of electromagnetic fields in a uniformly and longitudinally expanding quark-gluon plasma with chirality imbalance. Combining the constitutive equations of CSMHD under these assumptions, we arrive, as expected, at two distinct rotating and nonrotating solutions for electromagnetic fields. The rotation occurs with increasing rapidity and a constant angular velocity ${\ensuremath{\omega}}_{0}$. Remarkably, the relative angle between the electric and magnetic fields, $\ensuremath{\delta}$, turns out to be given by the coefficient of AH current ${\ensuremath{\kappa}}_{E}$ and the electric conductivity of the medium $\ensuremath{\sigma}$, as $\ensuremath{\delta}={\mathrm{tan}}^{\ensuremath{-}1}({\ensuremath{\kappa}}_{E}/\ensuremath{\sigma})$. Whereas the nonrotating solution implies the AH coefficient to be vanishing, and thus nonrotating electric and magnetic fields to be either parallel or antiparallel, the relative orientation of rotating electric and magnetic fields and the evolution of the CM conductivity ${\ensuremath{\kappa}}_{B}$ are strongly affected by nonvanishing ${\ensuremath{\kappa}}_{E}$. We explore the effect of positive and negative ${\ensuremath{\omega}}_{0}$ on the evolution of the CM current, and show, in particular, that a rotation of electromagnetic fields with negative ${\ensuremath{\omega}}_{0}$ implies a sign flip of the CM current in a chiral fluid with nonvanishing AH current.

Motivated by the recently found realization of the $1+1$ dimensional Bjorken flow in ideal and nonideal relativistic magnetohydrodynamics (MHD), we use appropriate symmetry arguments, and determine the evolution of magnetic fields arising from the $3+1$ dimensional self-similar and Gubser flows in an infinitely conductive relativistic fluid (ideal MHD). In the case of the $3+1$ dimensional self-similar flow, we arrive at a family of solutions, that are related through a differential equation arising from the corresponding Euler equation. To find the magnetic field evolution from the Gubser flow, we solve the MHD equations of a stationary fluid in a conformally flat $dS^{3}\times E^{1}$ spacetime. The results are then Weyl transformed back into the Minkowski spacetime. In this case, the temporal evolution of the resulting magnetic field is shown to exhibit a transition between an early time $1/t$ decay to a $1/t^{3}$ decay at a late time. Here, $t$ is the time coordinate. Transverse and longitudinal components of the magnetic fields arising from these flows are also found. The latter turns out to be sensitive to the transverse size of the fluid. In contrast to the result arising from the Gubser flow, the radial domain of validity of the magnetic field arising from the self-similar flow is highly restricted. A comparison of the results suggests that the (conformal) Gubser MHD may give a more appropriate qualitative picture of the magnetic field decay in the plasma of quarks and gluons created in heavy ion collisions., Comment: 26 pages, 10 figures

In the bearing health assessment issues, using the adaptive nonstationary vibration signal processing methods in the time-frequency domain, lead to improving of early fault detection. On the other hand, the noise and random impulses which contaminates the input data, are a major challenge in extracting fault-related features. The main goal of this paper is to improve the Ensemble Empirical mode decomposition (EEMD) algorithm and combine it with a new proposed denoising process and the higher order spectra to increase the accuracy and speed of the fault severity and type detection. The main approach is to use statistical features without using any dimension reduction and data training. To eliminate unrelated components from faulty condition, the best combination of denoising parameters based on the wavelet transform, is determined by a proposed performance index. In order to enhance the efficiency of the EEMD algorithm, a systematic method is presented to determine the proper amplitude of the additive noise and the Intrinsic Mode Functions (IMFs) selection scheme. The fault occurrence detection and the fault severity level identification are performed by the Fault Severity Index (FSI) definition based on the energy level of the Combined Fault-Sensitive IMF (CFSIMF) envelope using the central limit theorem. Also, taking the advantages of a bispectrum analysis of CFSIMF envelope, fault type recognition can be achieved by Fault Type Index (FTI) quantification. Finally, the proposed method is validated using experimental data set from two different test rigs. Also, the role of the optimum denoising process and the algorithm of systematic selection of the EEMD parameters are described regardless of its type and estimating the consistent degradation pattern.

Experimental and theoretical studies of steam methane reforming reactions with different amount of hydrogen sulfide in the feed gas are presented. A two dimensional pseudo-heterogeneous model is developed to simulate methane steam reforming reactions in a packed bed tubular reactor. This model is based on mole and energy balance equations for the catalyst and the fluid phases. Attention is given to the analysis of sulfur negative effects on reforming process. A parametric study is done and effects of different steam to carbon ratios, space velocities, temperatures and different amount of sulfur on methane conversion and temperature distribution within the reactor are investigated. The results are verified comparing to the experimental results. It is shown that even presented in the gas at very low concentration levels (ppm), sulfur drastically decreases the conversion of methane. The obtained results play a key role in design and optimization of an actual reactor.

Data-driven programming models such as many-task computing MTC have been prevalent for running data-intensive scientific applications. MTC applies over-decomposition to enable distributed scheduling. To achieve extreme scalability, MTC proposes a fully distributed task scheduling architecture that employs as many schedulers as the compute nodes to make scheduling decisions. Achieving distributed load balancing and best exploiting data locality are two important goals for the best performance of distributed scheduling of data-intensive applications. Our previous research proposed a data-aware work-stealing technique to optimize both load balancing and data locality by using both dedicated and shared task ready queues in each scheduler. Tasks were organized in queues based on the input data size and location. Distributed key-value store was applied to manage task metadata. We implemented the technique in MATRIX, a distributed MTC task execution framework. In this work, we devise an analytical suboptimal upper bound of the proposed technique, compare MATRIX with other scheduling systems, and explore the scalability of the technique at extreme scales. Results show that the technique is not only scalable but can achieve performance within 15% of the suboptimal solution. Copyright © 2015 John Wiley & Sons, Ltd.

This paper presents a convergence of distributed key-value storage systems in clouds and supercomputers. It specifically presents ZHT, a zero-hop distributed key-value store system, which has been tuned for the requirements of high-end computing systems. ZHT aims to be a building block for future distributed systems, such as parallel and distributed file systems, distributed job management systems, and parallel programming systems. ZHT has some important properties, such as being lightweight, dynamically allowing nodes join and leave, fault tolerant through replication, persistent, scalable, and supporting unconventional operations such as append, compare and swap, callback in addition to the traditional insert/lookup/remove. We have evaluated ZHT's performance under a variety of systems, ranging from a Linux cluster with 64 nodes, an Amazon EC2 virtual cluster up to 96 nodes, to an IBM Blue Gene/P supercomputer with 8K nodes. We compared ZHT against other key-value stores and found it offers superior performance for the features and portability it supports. This paper also presents several real systems that have adopted ZHT, namely, FusionFS a distributed file system, IStore a storage system with erasure coding, MATRIX distributed scheduling, Slurm++ distributed HPC job launch, Fabriq distributed message queue management; all of these real systems have been simplified because of key-value storage systems and have been shown to outperform other leading systems by orders of magnitude in some cases. It is important to highlight that some of these systems are rooted in HPC systems from supercomputers, while others are rooted in clouds and ad hoc distributed systems; through our work, we have shown how versatile key-value storage systems can be in such a variety of environments. Copyright © 2015 John Wiley & Sons, Ltd.

For unreplicated three-way layouts, the usual F-test can not be used for testing three-factor interaction and it is common to base the analysis on the model without three-factor interaction. This may lead to misleading results if three-factor interaction is actually present. We propose a simple and flexible procedure for testing three-factor interaction when one of the factors has at least four levels. This procedure is not based on a specific functional form for the interactions, and its usefulness is illustrated with several examples. (We are not aware of any method which is not based on assuming a specific functional form for the three-factor interaction.) We compare the performance of our procedure with several other tests via an extensive simulation study. This simulation study shows that there is no test of interaction which can detect all patterns of interaction. Therefore, in the absence of prior information regarding the structure of three-factor interaction, no test can be preferred to other tes...

We consider the problem of comparing k regression models, when the variances are not assumed to be equal. For this problem, the classical F test can lead to misleading results, and there is no simple test which adequately controls the size when the sample sizes are small. For k = 2, the most widely used test is the “weighted F test,” also known as the “asymptotic Chow test.” But this test does not work well for small samples, and various modifications have been proposed in the literature. For k > 2, few tests are available and only the parametric-bootstrap (PB) test of Tian et al. (2009) controls the size fairly adequately. In this article, we propose three fairly simple F tests which can easily be applied in the general case, k ⩾ 2, and avoid the complications of the PB test. Our simulations indicate that these tests have satisfactory performance. Also, our simulations confirm that the power properties of our proposed tests are similar to the PB test. Therefore, our proposed tests provide simple alternat...

Comment les futur-e-s enseignant-e-s primaires en charge de l’anglais perçoivent-ils leur représentation et maitrise à la langue dans le but de l’enseigner ; c’est à cette question que nous tenterons de répondre à travers notre mémoire professionnel. Pour ce faire, nous avons divisé notre travail en deux parties distinctes. La première étant les aspects théoriques regroupant comme concepts principaux l’aisance, les représentations, les stéréotypes et l’insécurité linguistique. La deuxième étant l’analyse de nos résultats basée sur les réponses d’un questionnaire informatique envoyé à l’ensemble des étudiants de deuxième et troisième année de la HEP VD ayant pour option l’anglais dans leur formation. Notre recherche tend à se questionner et s’informer sur les représentations et l’aisance actuelle des futur-e-s enseignant-e-s dans leur maîtrise face à la langue anglaise dans le but de l’enseigner dans les degrés primaires. Pour cela, nous nous sommes intéressées à la perception, l’aisance et les représentations de la langue anglaise par nos sujets et plus précisément l’utilité de l’enseignement de cette langue dans les degrés primaire perçue par nos répondants. Pour terminer, nous nous intéresserons à l’utilité de bénéficier d’un cours supplémentaire d’anglais afin de perfectionner son niveau de langue dans le but de l’enseigner.

The evolution of electromagnetic and thermodynamic fields in a non-ideal fluid are studied in the framework of ultrarelativistic transverse magnetohydrodynamics (MHD), which is essentially characterized by electric and magnetic fields being transverse to the fluid velocity. Extending the method of self-similar solutions of relativistic hydrodynamics to the case of non-conserved charges, the differential equations of non-ideal transverse MHD are solved, and two novel sets of self-similar solutions are derived. The first set turns out to be a boost-invariant and exact solution, which is characterized by non-rotating electric and magnetic fields. The second set is a non-boost-invariant solution, which is characterized by rotating electric and magnetic fields. The rotation occurs with increasing rapidity $\eta$, as the angular velocity is defined by $\omega_{0}\equiv\frac{\partial\zeta}{\partial\eta}=\frac{\partial\phi}{\partial\eta}$, with $\zeta$ and $\phi$ being the angles of electric and magnetic vectors with respect to a certain axis in the local rest frame of the fluid. For both sets of solutions, the electric and magnetic fields are either parallel or anti-parallel to each other. Performing a complete numerical analysis, the effects of finite electric conductivity as well as electric and magnetic susceptibilities of the medium on the evolution of rotating and non-rotating MHD solutions are explored, and the interplay between the angular velocity $\omega_{0}$ and these quantities is scrutinized. The lifetime of electromagnetic fields and the evolution of the temperature of the electromagnetized fluid are shown to be affected by $\omega_{0}$., Comment: 33 pages, 18 figures

Background and aims Operating room is a quiet place and serious that there will be any extra noise to the distraction and interfere with verbal communication between people. However, numerous studies have shown that a significant relaxation in the operating room does not establish silence and may be used to achieve this purpose; the quiet sound of music. This study is a systematic review about the effects of music on the healing process of patients in the operating room. Methods We systematically reviewed the literature from Medline (PubMed), The Cochrane Library, Ovid, Scopus, Embase, ProQuest and Google Scholar published between 2000 and 2016. The search strategy included a combination of Mesh and Free Keywords, “Music”, “Music Therapy”, “Operating room”, “operating theatre”, “surgery room”, in all fields. Also the publication types of review and articles were included and meetings abstract, editorials, brief commentaries, letters, errata and papers that Subtopics were also excluded. Results Our initial search identified 480 abstracts. Application of the inclusion/exclusion criteria resulted in 17 articles for review. Findings indicated that music has a positive effect on patient perception of anxiety, pain and satisfaction some times, but it was relatively ineffective when there is a severe pain. Also findings showed that loud music played in operating theatres hinders the ability of nurses to hear instructions. On the other hand surgeons speed increase with music played in operating theaters. Discussion Music is a free way to improve patients stress and pain before and during surgery. Although there isn't enough evidence in order to draw a net conclusion about the effect of music in operating rooms.

Suppose that random samples are taken from $$k$$ k treatment groups and $$l$$ l control groups, where the observations in each group have a two-parameter exponential distribution. We consider the problem of constructing simultaneous confidence intervals for the differences between location parameters of the treatment groups and the control groups when the scale parameters may be unequal. Using the parametric bootstrap approach, we develop a new multiple comparisons procedure when the scale parameters and sample sizes are possibly unequal. We then present a simulation study in which we compare the performance of our proposed procedure with two other procedures. The results of our simulations indicate that our proposed procedure performs better than other procedures. The usefulness of our proposed procedure is illustrated with an example.

For constructing simultaneous confidence intervals for the ratios of means of several lognormal distributions, we propose a new parametric bootstrap method, which is different from an inaccurate parametric bootstrap method previously considered in the literature. Our proposed method is conceptually simpler than other proposed methods, which are based on the concepts of generalized pivotal quantities and fiducial generalized pivotal quantities. Also, our extensive simulation results indicate that our proposed method consistently performs better than other methods: its coverage probability is close to the nominal confidence level and the resulting intervals are typically shorter than the intervals produced by other methods.

Exciting the mechanical resonance mode and vibration caused by non-smooth trajectories can cause some failure in the structure of the robot and its actuators. This work proposes a smooth trajectory planning for 3 degree of freedom (dof) 3-upu parallel manipulator. We have used optimization method to define the smooth trajectory for this robot. In this paper an objective function has been used which contain a term related to the total execution time and a term corresponding to the integral of squared jerk. Some constraints have been applied to the problem as the input of our system. Task space and joint space trajectory are then considered as the output. In this method optimization techniques such as genetic algorithm and fmincon (function of MatLabTM ) have been investigated. Six via points have been considered and B-splines have been used to present kinematic quantities.

For testing the equality of scale parameters of several inverse Gaussian distributions, we propose an exact test which is much easier to implement than the test proposed by Chang et al. (2012) . Our simulations indicate that our proposed test is also more powerful.

We derive best-possible bounds on the class of copulas with known values at several points, under the assumption that the points are either in “increasing order” or in “decreasing order”. These bounds may be used to establish best-possible bounds on Kendall's τ and Spearman's ρ, for such copulas. An important special case is when the values of a copula are known at several diagonal points. We also use our results to establish best-possible bounds on the distribution function of the sum of two random variables with known marginal distributions when the values of the joint distribution function are known at several points.

Analysis of covariance (ANCOVA) is the standard procedure for comparing several treatments when the response variable depends on one or more covariates. We consider the problem of testing the equality of treatment effects when the variances are not assumed to be equal. It is well known that classical F test is not robust with respect to the assumption of equal variances and may lead to misleading conclusions if the variances are not equal. Ananda (1998) developed a generalized F test for testing the equality of treatment effects. However, simulation studies show that the actual size of this test can be much higher than the nominal level when the sample sizes are small, particularly when the number of treatments is large. In this article, we develop a test using the parametric bootstrap approach of Krishnamoorthy et al. (2007). Our simulations show that the actual size of our proposed test is close to the nominal level, irrespective of the number of treatments and sample sizes. Our simulations also indicat...

Product gas produced by biomass gasification contains small amounts of sulfur compounds (hydrogen sulfide) which can reduce catalyst activity during steam reforming process. Sulfur removal has a negative effect on process efficiency and steam reforming has to be run without cleaning the gas prior to the reactor. It is therefore of interest to investigate the effect of sulfur on the performance of steam reforming reactions. In this work a packed bed reactor filled with nickel based catalysts is mathematically modeled to simulate the steady state pseudo-heterogeneous equations representing heat and mass transfer in the reactor tube. Catalytic bed is subjected to hydrogen sulfide and an isotherm model for the sulfur coverage on the Ni surface is considered to exactly investigate sulfur poisoning effects on methane conversion, hydrogen yield, carbon dioxide and carbon monoxide concentration. It is shown that even when present in the hydrocarbon feedstock in small quantities, (ppm) levels, sulfur can have a significant effect in methane conversion and temperature distribution within the reactor.

We present simultaneous fiducial generalized confidence intervals for the successive differences of the location parameters of several exponential distributions with unequal scale parameters, and show that they have correct coverage probability asymptotically. Our simulation results indicate that our proposed procedure performs better than the procedure of Maurya et al. (2011b) .

A mathematical model is developed to simulate synthesis gas production by methane steam reforming process in a fixed bed reactor filled with catalyst particles. Due to the endothermic nature of the reforming reactions heat is supplied into the reactor by means of electrical heating, therefore, the reactor and catalyst particles are exposed to significant axial and radial temperature gradients. A pseudo heterogeneous model is used in order to exactly represent diffusion phenomena inside the reactor tube. Heat and mass transfer equations are coupled with detailed reaction mechanisms and solved for both the flow phase and within the catalyst pellets. The reaction has been investigated from a modeling view point considering the effect of different temperatures ranging from 873 to 1073 (K) on methane conversion and hydrogen yields. The result provides temperature and concentration distribution along the reactor axial and radial coordinates and strong radial temperature gradients particularly close to the entrance of the reactor have been found.

Data Analytics has become very popular on large datasets in different organizations. It is inevitable to use distributed resources such as Clouds for Data Analytics and other types of data processing at larger scales. To effectively utilize all system resources, an efficient scheduler is needed, but the traditional resource managers and job schedulers are centralized and designed for larger batch jobs which are fewer in number. Frameworks such as Hadoop and Spark, which are mainly designed for Big Data analytics, have been able to allow for more diversity in job types to some extent. However, even these systems have centralized architectures and will not be able to perform well on large scales and under heavy task loads. Modern applications generate tasks at very high rates that can cause significant slowdowns on these frameworks. Additionally, over-decomposition has shown to be very useful in increasing the system utilization. In order to achieve high efficiency, scalability, and better system utilization, it is critical for a modern scheduler to be able to handle over-decomposition and run highly granular tasks. Further, to achieve high performance, Albatross is written in C/C++, which imposes a minimal overhead to the workload process as compared to languages like Java or Python. We propose Albatross, a task level scheduling and execution framework that uses a Distributed Message Queue (DMQ) for task distribution among its workers. Unlike most scheduling systems, Albatross uses a pulling approach as opposed to the common push approach. The former would let Albatross achieve a good load balancing and scalability. Furthermore, the framework has built in support for task execution dependency on workflows. Therefore, Albatross is able to run various types of workloads, including Data Analytics and HPC applications. Finally, Albatross provides data locality support. This allows the framework to achieve higher performance through minimizing the amount of unnecessary data movement on the network. Our evaluations show that Albatross outperforms Spark and Hadoop at larger scales and in the case of running higher granularity workloads.

The effects of finite magnetization and electric polarization on dissipative and non-dissipative (anomalous) transport coefficients of a chiral fluid are studied. First, using the second law of thermodynamics as well as Onsager's time reversal symmetry principle, the complete set of dissipative transport coefficients of this medium is derived. It is shown that the properties of the resulting shear and bulk viscosities are mainly affected by the anisotropy induced by external electric and magnetic fields. Then, using the fact that the anomaly induced currents do not contribute to entropy production, the corresponding algebro-differential equations to non-dissipative anomalous transport coefficients are derived in a certain derivative expansion. The solutions of these equations show that, within this approximation, anomalous transport coefficients are, in particular, given in terms of the electric susceptibility of the medium., Comment: V1: 14 pages (two-column), 1 table, no figure; V2: 20 pages (one-column), 1 table, no figure. Version accepted for publication in New Journal of Physics (2017)