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The purpose of this paper is calculating the availability of wireless sensor network for a virtual grid by using Markov model. Since, wireless sensor networks are constraints by energy, their energy consumption should be limited within a way to guarantee their quality of service. In this paper, availability and quality of service in a wireless sensor network with particular coverage are investigated by using an energy optimized algorithm and Markov process.

Efficient surrogate modelling of computer models (herein defined as simulators) becomes of increasing importance as more complex simulators and non-deterministic methods, such as Monte Carlo simulations, are utilised. This is especially true in large multidimensional design spaces. In order for these technologies to be feasible in an early design stage context, the surrogate model (oremulator) must create an accurate prediction of the simulator in the proposed design space. Gaussian Processes (GPs) are a powerful non-parametric Bayesian approach that can be used as emulators. The probabilistic framework means that predictive distributions are inferred, providing an understanding of the uncertainty introduced by replacing the simulator with an emulator, known as code uncertainty. An issue with GPs is that they have a computational complexity of O(N3) (where N is the number of data points), which can be reduced to O(NM2) by using various sparse approximations, calculated from a subset of inducing points (where M is the number of inducing points). This paper explores the use of sparse Gaussian process emulators as a computationally efficient method for creating surrogate models of structural dynamics simulators. Discussions on the performance of these methods are presented along with comments regarding key applications to the early design stage.

The paper deals with eigenvalues excited-state energy eigenvalues and wave-function of a particle under harmonics oscillator asymmetric potential using numerical shooting method. The numerical shooting method is generally regarded as one of the most efficient methods that give very accurate results because it integrates the Schrodinger equation directly, though in the numerical sense. If the value of parameter μ is small the energy eigenvalues of single particle will large and the parameter μ large the energy eigenvalues of single particle will small.

Impulse facilities generate transient high-velocity gas flows for ground testing in aerodynamics. The expansion tube is the facility type with the highest performance capability in terms of total flow enthalpy and total pressure, and is particularly useful for studies of atmospheric re-entry, chemical kinetics, scramjet flight and supersonic combustion. In operation, a thin film diaphragm that initially partitions two tube sections is required to rupture under the force of a shock-wave. Fragmented pieces are accelerated with the flow and can damage test models and instrumentation, and the rupture process itself affects flow properties. It has been proposed to replace the diaphragm with a fast open valve that clears the tube prior to shock arrival. This paper investigates the effect of early valve opening on the test flow.An inviscid, axisymmetric model was created using Eilmer3, a compressible CFD solver developed at the University of Queensland. Early valve opening was simulated at varying times for instantaneous diaphragm removal. The result was the formation of a secondary shock and expansion wave. The primary shockwave reaches the test section at a higher velocity due to passing through the expansion wave, creating a faster, higher-pressure test flow, but also higher temperature, leading to substantially reduced Mach number. The interactions with the secondary waves were found to cause unsteadiness in test flow properties.

The computational fluid dynamics solver Eilmer has proven useful to The University of Queensland’s Centre for Hypersonics for its ability to simulate high-speed compressible flows. In Eilmer, turbulence is modelled using Wilcox’s 2006 k-ω model. While the turbulence model implementation has been validated for two-dimensional and axisymmetric flows, validation is required for three-dimensional flows. The present paper describes the progress of the validation of the k-ω turbulence model for two three-dimensional test cases. A case featuring Mach 4.5 air flow over a flat plate produced results that correlated with previous numerical results within 4%. A second case featuring the injection of Mach 1 air into a Mach 4 air cross-flow produced results indicating that the code successfully captured the main flow features.

This paper reports the results on cracking propagation and pattern of reinforced concrete (RC) beam conducted using irregular-shaped Polyethylene Terephthalate (IPET) as a fibre. Three volume fraction of IPET fibre is used namely, 0.5%, 1% and 1.5%. All RC beam specimens are tested under four point loading under flexural capacity behaviour. Prior to structural test, the materials properties which include the compressive and tensile strength test and modulus of elasticity test were determined. The results than are compared with control RC beam. It is found that the RC beam with IPET fibre does not significantly change the behaviour of failure mode, cracking propagation and pattern compared to control RC beam.

This paper presents the formation of highly crystalline ZIF-8 using microwave-assisted solvothermal method. The crystallinity of the ZIF-8 particles was characterized using X-ray diffraction. The lattice vibrations of the structure in the ZIF-8 framework were determined through Fourier transforms infrared spectroscopy. The morphology of the ZIF-8 particles was observed through scanning electron microscopy. The results showed that, 0.5 hour was sufficient for the formation of highly crystalline ZIF-8 particles using microwave-assisted solvothermal method under temperature 120 oC.

In this paper we find a general solution for the action function in the case of a heavy point moving on a sphere using the method of separation of the Hamilton-Jacobi equation variables. The solution contains two constants: the energy of a material point and the momentum projection onto a horizontal direction. We analyze the modes of a spherical pendulum oscillation. It is shown that the solution does not contain any errors of accumulation which are characteristic for evolution problems with long prediction periods.

This paper is primarily concentrated with determining aerodynamic characteristics and choosing the best angle of attack at a maximum lift and low drag for the FX 63-137 aerofoil at a low Reynolds number and a speed of 20m/s and 30m/s, by using subsonic wind tunnel through manufacturing the aerofoil by aluminum alloy using a CNC machine. The proposed methodology is divided into several stages. Firstly, manufacturing the aerofoil using an aluminum alloy. Secondly, the testing process is carried out using subsonic wind tunnel. Thirdly, the results are displayed and compared with results produced from related works, in order to find out the best angle of attack at a maximum lift.

Strength properties’ tests are conducted in the form of small clear sample. This paper aimed to acquire the strength group of fast-growing indigenous species of Aras and exotic species of Acacia mangium. Thus, the information of strength properties of species is acquired from strength property's test at green and air-dry conditions. The required information namely, bending parallel to grain, compression stress parallel to grain, shear parallel to grain and modulus of elasticity. The ultimate stresses obtained from strength properties of the species is to be converted into basic and grade stresses to determine the strength group of the species based on MS 544: Part 2 (2001). The results from the study indicated that, Acacia mangium classified under strength group SG5, whilst Aras was classified under strength group SG7. The timber is classified as medium density of Light Hardwood ranging from 0.37-0.52 g/cm3 at air-dry condition.

This paper reported the study of tensile properties of kenaf yarn fibre reinforced unsaturated polyester (UP) composites at different fibre orientations, i.e. 0o, ±45o and 90o. It is concluded that composites with 0o orientation show higher strength and stiffness than composites with ±45o and 90o angle fibre orientation. The highest value of stress is 29 MPa for 0o loading direction followed by ±45o loading direction (28 MPa) and 90o loading direction has the lowest stress value of 6 MPa. Tensile modulus results revealed the highest value of 10.61 GPa for 0o loading direction and the tensile modulus for 45o orientation of loading direction is 5 GPa, followed by the modulus for 90o of fibre loading direction of 1.2 GPa; which is the lowest.

Retracted paper: In recent years, much research has been devoted to the emulation of the Turing machine; unfortunately, few have simulated the emulation of the partition table. In fact, few cyberneticists would disagree with the construction of symmetric encryption, which embodies the structured principles of algorithms. We propose a novel heuristic for the synthesis of linked lists, which we call Carl.

Data replication techniques are used in cloud computing to reduce access latency, network bandwidth and enhance data availability, system reliability. Replica selection involves selecting the best replica location to access the data for job execution in cloud computing. In order to select the best replica, a novel response time-driven replica selection approach based on Dirichlet probability distribution (DPRS) is proposed in this paper. Dirichlet PDF is the conjugate prior of categorical distribution to predict the posteriori value. The response time is calculated based on the network parameters such as network bandwidth, file size and access latency. The best replica can be predicted in corresponding with the historical log file by using Dirichlet PDF. Simulation results show that DPRS method conducts high performance in lower mean response time, while compared with No replica, LRU and LFU strategies.

A solar air heater (SAH) is a simple heater using solar radiation that is useful for drying or space heating. Unfortunately, heat transfer from the absorber plate to the air inside the solar air heater is low. Some researchers reported that obstacles are able to improve the heat transfer in a flat plate solar air collector and others found that a v-corrugated absorber plate gives better heat transfer than a flat plate. Yet, no work of combining these two findings is found.This paper describes the result of experimental study on a SAH with v-corrugated absorber plate and obstacles bent vertically started from 80oto 0owith interval 10oon its bottom plate. Experiments were conducted indoor at five different Reynolds numbers (1447 Re 7237) and three different radiation intensities (430, 573, and 716 W/m2).It is found that the obstacles improve SAH performance. Both the air temperature rise and efficiency increase with inserting obstacles bent at any angle vertically. Unfortunately, the air pressure drop is increasing, too. Obstacles bent vertically at smaller angle (means more straight) give higher air temperature rise and efficiency. However, the optimum angle is found 30o. The air temperature rise and efficiency will be 5.3% lower when the obstacles bent 30oinstead of 0o, but the pressure drop will be 17.2% lower.

In this paper, the discontinuous Galerkin method (DG) is applied to solve the 2D Euler equation. DG can be easily used in the unstructured girds, which has advantages in dealing with problems with complex boundaries. High order accuracy is achieved by higher order polynomial approximations within elements. In order to capture the shock without oscillation, the limiter is also applied. The performance of DG is illustrated by three numerical experimental tests, which show the potential of DG in engineering applications. The vortex propagation problem is to verify high-order accuracy of DG, while Sob problem and forward step problem are used to illustrate the ability to capture shock.

A new derivation of Transient Grounding Resistance (TGR) has been proposed in this paper. Take grounding system as naked antenna in lossy medium, and then get the input resistance of naked antenna in a given frequency based on Helen current integral equations. With inverse Fourier transform, the resistance calculation equations can be translated from frequency domain to time domain. The result can be applied to design a new grounding system and to calculate its TGR .

This paper researches the product pricing problems of cruise companies in the oligopoly market, discusses a cooperative game model and a non cooperative game model, and gives equilibrium results of pricing game between two oligopoly companies by analyzing the solution of models.

Turbo codes have a wide range of applications in 3G mobile communications, deep-sea communications, satellite communications and other power constrained fields. In the paper, the Turbo Code Decoding Principle and several major decoding methods are introduced. Simulations of Turbo code performance under different parameters of AWGN channel are made and the effects of the different interleaving length, the number of iterations, and the decoding algorithm to Turbo code performance are also discussed in AWGN channel. Simulation results show that under the same signal-to-noise ratio, the more the number of iterations is, the longer the sequence of information is, and the more excellent decoding algorithm is, the better the performance of Turbo codes is.

In digital image processing, Fourier transform is an important algorithm of image transformation. In order to improve the speed of Fourier transform, the paper proposes to deal with the image with GPU parallel computing through the method of GPU accelerating MATLB. The relationship of data scale and calculation speed is analyzed through the traditional CPU serial operation and GPU parallel computing. Computer simulations verify that the calculation speed can be improved by GPU about large scale data.

This paper gives the research on the anti-noise AM spot jamming performance of pseudo-random binary code phase modulation and sine FM combined fuze based on the criterion of signal to jamming ratio gain. First, the overall signal to jamming ratio gain of its receiver is reduced in detail under the noise AM spot jamming, then, the factors affecting anti-jamming performance are analyzed. The results show that the PRBC-SFM combined fuze has stronger performance of anti-noise AM spot jamming, and its anti-jamming performance can be improved effectively by choosing the parameters of the n-th order Bessel function, and along with decreasing periods and narrowing code width, Doppler frequencys influence on the anti-noise AM spot jamming performance of the PRBC-SFM combined fuze is debased.

Low temperature radio frequency plasma is widely used in low temperature plasma processing medium for material processing in many fields including microelectronics, aerospace, and the biology. For proper utilization of the process, it is very much important to know the plasma parameters. In this paper a novel technique is used to determine the plasma parameters from the electrical discharge characteristic and the power balance method. The homogeneous discharge model is used to evaluate the relation between the plasma parameters with the discharge characteristics. The electron density and temperature is found to be well agree with the Langmuir probe data in the range of 0.5x1016 to 45x1016 cm-3 and 1.4 to 1.6 ev for wide range of rf power.

This paper describes uniaxial compression tests on a melt-extruded closed-cell Low-Density Polyethylene (LDPE) foam. The stress-strain response shows the mechanical behaviour of the foam is predominantly transversely isotropic viscoelastic and compressible. Images analysis is used to estimate the Poisson’s ratio under large strains. When the deformation is less than 5 percent, the kinematics and mechanical response of the polymer foam can be well-described by a linear compressible transversely isotropic elastic model. For large strain, a method of manipulating experimental data obtained from testing in the principal and transverse directions (stress vs strain and Poisson’s ratio) in order to estimate the uniaxial compression response of the foam at any arbitrary orientation is proposed. An isotropic compressible hyperfoam model is then used to implement this behaviour in a finite element code.

Vibrational moulding process has a remarkable effect on the properties of castings during solidification processing of metals, alloys, and composites. This research paper discusses on the investigation of mechanical vibration mould effects on the tensile properties of titanium carbide particulate reinforced LM6 aluminium alloy composites processed with the frequencies of 10.2 Hz, 12 Hz and 14 Hz. In this experimental work, titanium carbide particulate reinforced LM6 composites were fabricated by carbon dioxide sand moulding process. The quantities of titanium carbide particulate added as reinforcement in the LM6 alloy matrix were varied from 0.2% to 2% by weight fraction. Samples taken from the castings and tensile tests were conducted to determine the tensile strength and modulus of elasticity. The results showed that tensile strength of the composites increased with an increase in the frequency of vibration and increasing titanium carbide particulate reinforcement in the LM6 alloy matrix.

This article reports an accurate analysis approach of finite element modeling and optical modeling. It has been used for design and analysis of many opto-mechanical systems such as large telescopes and laser systems. The approach is to represent mirror surface deformation derived from finite element analysis (FEA) by Zernike polynomials, such that the impact of deformation on optical system performance can be evaluated by optical design and analysis program. The methodology of shell-based and solid-based finite element modeling and the comparison of their results have been described in this paper. The result shows that the deformation of the light-weighted mirror designed by this approach fulfills the requirements of optical design. The simulation results of shell based FE model are in good agreement with those of solid based FE model.

The achievement of high levels of confidence in finite element models involves their validation using measured responses such as static strains or vibration mode shapes. A huge amount of data with a high level of information redundancy is usually obtained in both the detailed finite element prediction and the full-field measurements so that achieving a meaningful validation becomes a challenging problem. In order to extract useful shape features from such data, image processing and pattern recognition techniques may be used. One of the most commonly adopted shape feature extraction procedures is the Fourier transform in which the original data may be expressed as a set of coefficients (coordinates) of the decomposition kernels (bases) in the feature space. Localised effects can be detected by the wavelet transform. The acquired shape features are succinct and therefore simplify the model validation, based on the full-field data, allowing it to be achieved in a more effective and efficient way. In this paper, full-field finite element strain patterns of a plate with a centred circular hole are considered. A special set of orthonormal shape decomposition kernels based on the circular Zernike polynomials are constructed by the Gram-Schmidt orthonormalization process. It is found that the strain patterns can suitably be represented by only a very small number of shape features from the derived kernels.