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Wrinkling is one of the major defects in forming processes of auto-body panels. This paper focuses on application of universal formability technology to analyze and eliminate wrinkling defect. To analyze refinedly and eliminate efficiently, universal formability technology is introduced into finite element environment. This paper presents a procedure of formability simulation analysis for wrinkles appeared on an auto fender model. The analysis results provide the approaches to eliminating wrinkles, which demonstrates the effectiveness of universal formability technology to analyze wrinkling phenomenon. The study also shows the feasibility of universal formability technology introduced into finite element environment.

Two phase titanium alloy-TC11 alloy and Superalloy-IN718 alloy are being considered for high-temperature structural applications in aero-engine because of their excellent mechanical properties at elevated temperatures. The mechanical properties of their forgings are sensitive to the microstructure. Therefore, it is crucial to obtain a corresponding microstructure by controlling the hot working process. For the forging of TC11 alloy, the ingot break down in the subtransus region is an important process which acted as the primary role in the transformation of lamellar structure to equiaxed one as well as its poor formability because of lower deformation temperature. In this paper, the lamellar globularization kinetics and fracture behavior during forging are studied and modeled. For the hot forging of IN718 alloy. the grain size evolution is an important process. As the δ phase in the alloy can control grain growth through the strong pinning effect, the effect of δ phase on the microstructure evolution during hot working has been considered in this paper, and the microstructure evolution model has been established. As a applications, The lamellar globularization and fracture during the subtransus cogging process of large size TC11 alloy billet, and the microstructure development during the hot forging process of IN718 alloy turbine disk have been investigated commercial FE Software with user subroutines. The prediction results showed good agreement with the actual ones.

Bi2Sr2CaCu2Ox/AgMg (Bi2212) multi filamentary superconducting round wires (RWs) can be only potential candidate for constructing the superconducting magnet with higher magnetic field (>25T). Very complicated microstructure of Bi2212 RWs has been found by recent SEM studies, and then the vital problems of Characterization of this unique microstructure and further exploration of the correlation of macro electromechanical properties with this microstructure arise. In this paper, it is firstly found that the rough surface of individual filaments can be well characterized by fractals. On the geometrical model with the fractal simulation of the rough surface, stress-strain relation of Bi2212 RWs has been investigated. The modelling result with considering the rough surface has a better agreement to the experimental data.At the request of the authors, and with the agreement of the Proceedings Editor, the above paper in AIP Proceedings has been retracted (as of 26 November 2013) due to a prior publication by the ...

Integration of optics with genetics to control any events within particular cells of living tissue is known as optogenetics. Term ‘Optogenetics’ was introduced in early 1970’s. It is the marriage between optics and genetics to control specific cells of living tissue. This paper introduces the field of optogenetics and its emergence from biophotonics and summarizes the role of optics in the field of optogenetics. This paper also provides a brief survey of some of the ongoing and future research on Optogenetics.

Complex-valued harmonic functions that are univalent and sense-preserving in the open unit disk Δ can be written in the form f = h+g¯, where h and g are analytic in Δ several mathematicians examined classes of complex harmonic functions in the unit disk with some coefficient conditions. In this paper we introduce some results which generalize problems considered in other previous papers. The main results concern starlikeness and convexity of harmonic functions satisfying a three parameter coefficient condition.

As advancing application of soft computation technique in oil and gas industry, Genetic Algorithm (GA) also shows contribution in geophysical inverse problems in order to achieve better results and efficiency in computational process. In this paper, I would like to show the progress of my work in inverse modeling of time-lapse gravity data uses value encoding with alphabet formulation. The alphabet formulation designed to provide solution of characterization positive density change (+Δρ) and negative density change (-Δρ) respect to reference value (0 gr/cc). The inversion that utilize discrete model parameter, computed with GA as optimization algorithm. The challenge working with GA is take long time computational process, so the step in designing GA in this paper described through evaluation on GA operators performance test. The performances of several combinations of GA operators (selection, crossover, mutation, and replacement) tested with synthetic model in single-layer reservoir. Analysis on sufficie...

Breakage of particles is a common phenomenon in handling, storage, transportation and processing of particles. Severity of breakage depends on particle loading types and environment as well as on the particle properties and strengths. The loading energy applied to the particle is used to generate new surfaces in the particles; as a result fragmentation of particles occurs. In this regard, the paper estimates the new surface generation during particle fracture using discrete element modeling. The paper also deals with the compression and impact loading of particles.

Making good decisions are very essential in any organization. However, the nature of the problems to be solved is becoming more complicated where as opposed to definiteness, elements of subjectivity and vagueness are now common. In this paper we propose a method of solving decision making problems using fuzzy number in order to cater the problem. We improvise the method of area dominance in ranking fuzzy number given by Tseng and Klein by introducing the concept of upper dominance. This proposed method can effectively rank combination of normal fuzzy numbers and non-normal fuzzy numbers. We implement the upper dominance concept in representing the confidence level of decision makers in solving problems. In addition, spread factor also incorporated in the ranking procedure in order to solve equality in ranking order. Several examples are given in the paper to illustrate the usefulness of this concept.

This paper is a review of the LDA(GGA)-1/2 method for band calculation. We review the many applications of the method: band gaps, semiconductor interfaces, semiconductor alloys. The number of applications where the method fails is minimal. Leading to results with a precision comparable to Hedin’s GW method, LDA-1/2 has the advantage of being orders of magnitude faster. The paper begins by a short theoretical review in which we try not repeat what is already published. Then we present some results that are scattered in the literature. We find that LDA(GGA)-1/2 is the recommended method for excited state energy calculations.

The measure of the retinal vessel diameter change reflects the vessel wall change which may be caused by a certain disease or physiological abnormality. There is no established method to measure the changes of the vessel edges across multiple retinal images over time. In this paper, we propose two methods to monitor the longitudinal change along the retinal vessel wall: 1) monitoring the change of the fixed points on the edges; and 2) calculating the change of the diameters vertical to the vessel direction. This paper will determine the proper method for the future analysis of the retinal pulsation and the longitudinal change along the retinal vessel wall. The comparison of the two methods shows that both methods can be used if the purpose is only to assess the difference of the vessel edges over time when the real value of the vessel diameter is not considered. Otherwise, centerline vertical diameter is complying more with the standard practice.

This paper is a continuation of our former work. In this paper, we compare the financial performance of the two banking systems that exist in Malaysia over two periods of time, during economic crisis (1997-1999) and after economic crisis (2001-2003). In order to see the conventional as well as Islamic bank's performance over these two periods of time, the study uses 10 financial ratios which are broadly categorized into 4 groups: (a) profitability ratios; (b) liquidity ratios; (c) risk and solvency ratios; and (d) efficiency ratios. Next, the study used T-test in determining the significance of the differential performance of the two banks over two periods of time. By using inter-bank comparison, the study found that, conventional bank has better performance, efficient, more profitable and has greater risk as compared to Islamic bank. However, in terms of utilizing asset, Islamic bank is better than conventional bank. As an overall, conventional bank is better in much aspect due to the longer history and experience in the industry than Islamic bank that start their operation in 1983.

The contribution is focused on risk analysis in food microbiology. This paper evaluates the effect of selected factors on tyramine production in bacterial strains of Lactococcus genus which were assigned as tyramine producers. Tyramine is a biogenic amine sythesized from an amino acid called tyrosine. It can be found in certain foodstuffs (often in cheese), and can cause a pseudo-response in sensitive individuals. The above-mentioned bacteria are commonly used in the biotechnological process of cheese production as starter cultures. The levels of factors were chosen with respect to the conditions which can occur in this technological process. To describe and compare tyramine production in chosen microorganisms, generalized regression models were applied. Tyramine production was modelled by Gompertz curves according to the selected factors (the lactose concentration of 0-1% w/v, NaCl 0-2% w/v and aero/anaerobiosis) for 3 different types of bacterial cultivation. Moreover, estimates of model parameters were calculated and tested; multiple comparisons were discussed as well. The aim of this paper is to find a combination of factors leading to a similar tyramine production level. © 2013 AIP Publishing LLC.

This paper presents a theoretical analysis of the demand for debt-based financing instruments of the Islamic banks. Debt-based financing, such as through baibithamanajil and al-murabahah, is by far the most prominent of the Islamic bank financing and yet it has been largely ignored in Islamic economics literature. Most studies instead have been focusing on equity-based financing of al-mudharabah and al-musyarakah. Islamic bank offers debt-based financing through various instruments derived under the principle of exchange (ukud al-mu’awadhat) or more specifically, the contract of deferred sale. Under such arrangement, Islamic debt is created when goods are purchased and the payments are deferred. Thus, unlike debt of the conventional bank which is a form of financial loan contract to facilitate demand for liquid assets, this Islamic debt is created in response to the demand to purchase goods by deferred payment. In this paper we set an analytical framework that is based on an infinitely lived representative agent model (ILRA model) to analyze the demand for goods to be purchased by deferred payment. The resulting demand will then be used to derive the demand for Islamic debt. We also investigate theoretically, factors that may have an impact on the demand for Islamic debt.

This paper has two purposes: the first is to determine the magnitude of the inconsistency in the overlap region of the water-aluminum and water-tin sub-ranges through investigation of calibration of the SPRTs. The other is to understand the characteristic of the inconsistency function in the region. In this paper, twenty one SPRTs were investigated. The results show that their inconsistencies are in the range from −1.26mK to 1.22mK except one of them is 4.08mK. The inconsistency function between the ITS-90 interpolations in the overlap region is unique cubic polynomial function with a movable real root, different from other inconsistency functions. By means of factoring, this paper gives an alternative form of the inconsistency function and makes an analysis of the roots and extrema of the function.

Operator allocation is one of the most important decisions that can affect productivity in labor-intensive manufacturing system. Improper decision on operator allocation will reduce company's throughput and increase waste. Therefore, all factors such as operators' performance and operational constraints need to be considered in making the best operator allocation decision. Most of previous studies used two phases methodology. In two phases methodology, they used operational constraints and treated all operators to have the same level of performance for making decision on operator allocation. Therefore, in this paper a three-phase methodology is proposed to determine the optimal operator allocation. This methodology advances the existing approach on operator allocation by combining operators' performance and operational constraints. The methodology starts with evaluating the operators' performance. Then, it is followed with determining inputs and outputs for operator allocation alternatives and it ends with determining the optimal operator allocation. This paper will give ideas and directions to the management of the manufacturing company in determining the optimal operator allocation decision.

This paper shows Electrical characterization of Dye Sensitized Solar Cell using natural dye, extracted from the pomegranate as a photo sensitizer and ZnO nanoparticles as semiconductor. The constituents of fabricated dye sensitized solar cell were working electrode, dye, electrolyte and counter electrode. ZnO nanoparticles were synthesized and used as semiconductor in working electrode. Carbon soot was used as counter electrode. The resistance of ZnO film on ITO film was found out. There was an increase in the resistance of the film and film changes from conducting to semiconducting. Photovoltaic parameters of the fabricated cell like Short circuit current, open circuit voltage, Fill factor and Efficiency were found out. This paper shows that usage of natural dyes like pomegranate juice as sensitizer enables faster and simpler production of cheaper and environmental friendly solar cell.

With high level of business competition, it is vital to have flexible staff that are able to adapt themselves with work circumstances. However, staff selection process is not an easy task to be solved, even when it is tackled in a simplified version containing only a single criterion and a homogeneous skill. When multiple criteria and various skills are involved, the problem becomes much more complicated. In adddition, there are some information that could not be measured precisely. This is patently obvious when dealing with opinions, thoughts, feelings, believes, etc. One possible tool to handle this issue is by using fuzzy set theory. Therefore, the objective of this paper is to review the existing fuzzy techniques for solving staff selection process. It classifies several existing research methods and identifies areas where there is a gap and need further research. Finally, this paper concludes by suggesting new ideas for future research based on the gaps identified.

In the present paper, the main factors which influence the accuracy of springback simulation are discussed, and the optimized parameters, which aim at obtaining an accurate springback simulation, and the full cycle simulation, which aims at the closest boundary condition between simulation and practice, are discussed. As a verification and comparison, an experimental part, Aluminum hood outer, is used and some good results are achieved. Based on the result of the springback verification, the minimum clamping concept for springback compensation is discussed and the compensation strategy is determined according to the springback behavior in different operations. Moreover, the springback in the car position and in the inspection tool is compared and a methodology of springback compensation without gravity is put forward. In the end, the basic principles of the rebuilding of class A surface is discussed and the comparison of geometrical deviation of the final part in tryout is given in this paper.

The shear stress generated in mine backfill slurries and fresh concrete contains both velocity gradient dependent and frictional terms, categorised as frictional viscous plastic fluids. This paper discusses application of the developed analytical solution for flow rate as a function of pressure and pressure gradient in discs, pipes and cones for such frictional Bingham-Herschel-Bulkley fluids. This paper discusses application of this continuum fluid model to industrial materials like mine and mineral slurries, backfills and fresh concrete tests.

The use of analysis techniques for industrial controller's analysis, such as Simulation and Formal Verification, is complex on industrial context. This complexity is due to the fact that such techniques require sometimes high investment in specific skilled human resources that have sufficient theoretical knowledge in those domains. This paper aims, mainly, to show that it is possible to obtain a timed automata model for formal verification purposes, considering the CAD model of a mechanical component. This systematic approach can be used, by companies, for the analysis of industrial controllers programs. For this purpose, it is discussed, in the paper, the best way to systematize these procedures, and this paper describes, only, the first step of a complex process and promotes a discussion of the main difficulties that can be found and a possibility for handle those difficulties. A library for formal verification purposes is obtained from original 3D CAD models using Software as a Service platform (SaaS) that, nowadays, has become a common deliverable model for many applications, because SaaS is typically accessed by users via internet access.

The present paper theoretically constructs the proton temperature anisotropy versus beta distribution by means of quasi-linear theory. It is shown that the simulated solar wind data distribution is constrained by the apparent mirror and oblique fire-hose marginal instability curves, which is consistent with observation. To achieve this closure, it is note that the actual magnetic field intensity near 1 AU is characterized intermediate-scale temporal variations. Making use of this fact, the present paper carries out the quasi-linear analysis of the temperature anisotropy-driven instabilities with adiabatically time-varying B field. This prescription successfully leads to the superficial mirror and oblique marginal instability constraints for the proton anisotropy, thus providing a possible explanation for the observation.

The impact of aerosols on global climate is an area of science that is dominated by uncertainty. The multi-model ensemble range of aerosol indirect forcing estimates has hardly changed through the last three IPCC assessments despite significant advances in our understanding of aerosol processes. In this paper we suggest that new approaches need to be taken to tackle the “uncertainty problem” head on. Here we show how emulators, Monte Carlotype sampling of model output and variance-based uncertainty analysis can be combined to generate an unprecedented amount of information about the magnitude and causes of uncertainty in global aerosol and radiative forcing. The impact of aerosols on global climate is an area of science that is dominated by uncertainty. The multi-model ensemble range of aerosol indirect forcing estimates has hardly changed through the last three IPCC assessments despite significant advances in our understanding of aerosol processes. In this paper we suggest that new approaches need to be ...

This paper explores the extension of the Legendre transform from scalar calculus to geometric calculus. In physics, the Legendre transform provides a change of variables to express equations of motion or other physical relationships in terms of the most convenient dynamical quantities for a given experimental or theoretical analysis. In classical mechanics and in field theory, the Legendre transform generates the Hamiltonian function of a system from the Lagrangian function or vice versa. In thermodynamics, the Legendre transform allows thermodynamic relationships to be written in terms of alternative sets of independent variables. In this paper, we review the properties of the Legendre transform in scalar calculus and show how an analogous transformation with similar properties may be constructed in geometric calculus.

This paper combines first-order system least-squares (FOSLS) and first-order system LL∗ (FOSLL∗) to create a Hybrid method. FOSLS minimizes the error, eh = uh− u, over a finite element subspace, V h, in the operator norm: uh = argminuh∈V h ‖L(uh− u)‖. Here, L is a first-order differential operator, obtained by possibly reformulating the original equations properly, such that c0‖e‖V h ≤ ‖L(uh− u)‖ ≤ c1‖e‖V h . Usually, V h is a subspace of H1, in which case this property of L is called H1-equivalence. This leads to many attractive numerical features of the resulting dicretized problem [5, 6, 11]. FOSLS also offers a locally sharp, globally reliable, and easily computable a posterior error estimate, which can be utilized for adaptive mesh refinement [3, 1]. The FOSLL∗ method seeks an approximation in the range of L∗, the adjoint of L: uh = L∗wh, with wh ∈ W h, a standard finite element space. FOSLL∗ minimizes the L2 norm of the error over L∗(W h), that is, wh = argminwh∈W h ‖L∗wh− u‖. For problems that are not smooth enough due to discontinuous coefficients, or nonsmooth boundary conditions, to name a few, H1-equivalence of L and its associated properties may be lost [12, 13, 17]. One of the solutions is to use FOSLL* [10, 15]. Unfortunately, FOSLL∗ does not have an easily computable error estimate. The Hybrid method attempts to retain the best properties of both FOSLS and FOSLL∗. This is accomplished by combining the FOSLS functional, the FOSLL∗ functional, and an intermediate term that draws them together. The FOSLS and intermediate terms in the Hybrid functional provide an effective a posteriori error measure. In this paper, we show that the Hybrid functional is coercive and continuous in a graph-like norm with modest coercivity and continuity constants, c0 = 1/3 and c1 = 3, which results in a better control of L2 error and mass conservation numerically, without going to a very fine grid. Numerical tests are provided to confirm the efficiency of the Hybrid method and effectiveness of the a posteriori error measure.

The present paper reports the influence in dielectric properties caused by gamma radiation. The dielectric parameters have been measured for both unirradiated and gamma irradiated 5CB nematic liquid crystal with temperature variation in the frequency range 100 Hz to 10 MHz. Dielectric permittivity with variation in temperature has also been observed. The dielectric permittivity is found to increase for gamma irradiated sample as compared to the unirradiated sample with variation in temperature and frequency and well explained in this paper.

Ni/Al2O3 (10 wt.% Ni) and Ni-Pt/Al2O3 (10 wt.% Ni, 0.5 wt.% Pt) were comparatively tested in the hydrogen selective catalytic reduction process (H2-SCR), at reaction temperatures below 350°C. Catalytic activity tests consisted in temperature programmed reactions (TPRea) under plug flow conditions from 50 to 350°C, with a temperature rate of 5°C/min, using a feed stream with a reactant ratio NO:H2 = 1:1.3 and a GHSV of 4500 h−1. Promotion with Pt increases the catalytic performances of the Ni based catalyst, in respect to NO conversion, N2 selectivity and N2 yield. The reaction temperatures for NO conversion above 95% decrease significantly due to Pt addition, from 250°C for Ni/Al2O3 to 125°C for Ni-Pt/Al2O3. Characterization of catalysts was performed by: X ray powder diffraction (XRD) for the estimation of Ni crystallite size, temperature programmed reduction (TPR) for the catalyst reducibility, temperature programmed desorption of hydrogen (H2-TPD) for the investigation of active sites and metal dispersion on the support, N2 adsorption-desorption isotherms at −196°C for the determination of total specific surface area and pore size distribution, and H/D isotopic exchange on the catalyst surface.At the request of the Proceedings Editor, and all authors of the paper, an updated version of this article was published on 14 January 2014. Data presented in Table 1 of the original paper contained errors which have been corrected in the updated and re-published article. The Corrigendum attached to the corrected article PDF file explains the errors in more detail.

Many innovative processes and newer materials are preferred over conventional methods in sheet metal forming and automotive industry to increase the efficiency on many aspects. These innovative processes include complex strain loading on sheet metal during forming. On the other hand newer materials behave differently in these innovative process conditions. Due to these changes the material characterization came as crucial investigation. Hole expansion process is one of the materials mechanical characterization which was investigated in this paper. Hole expansion capacity of the material seems less dependent on materials ductility if the hole surface quality is poor. Crack generation is one of the common failures in this process. Advanced high strength steels which are oriented towards multiphase structure, found more prone to this factor. Due to complexity in material microstructure each phase behaves independent to each other during loading. In this paper multiphase steel CPW800 was investigated through hole expansion process. Hole punching test was performed with punching and broaching combo geometries which is not discussed in this paper. Limit strain was measured for the hole expanded sample and compared with the FLD of this material. Furthermore numerical simulations were performed to validate with experiments. In addition limit strains was predicted and compared with the experimental results.

In this paper, effects of different modeling of cell-face velocities in convection term on accuracy and convergence behavior of the solution are studied. Three different upwind schemes, namely first order mass weighted upwind scheme, second order mass weighted upwind scheme and the modified version of physical influence scheme are used for modeling of convected velocities. Discussions are focused on the collocated scheme of Karimian and Schneider in the context of control volume finite element method. The modified version of this scheme, proposed by Alisadeghi and Karimian, has been used for modeling of mass conserving velocities in the present paper. Results of this method, then are compared with the results of pressure weighted interpolation method of Rhie and Chow. The steady-state flow in a two-dimensional driven cavity is studied for the comparison and validation of the numerical results. In general, the physical influence scheme gives the best accuracy among the three schemes.

In this paper a possibility of introducing new software metric is explored. The new metric reflects the recursive complexity i.e., the complexity of recursive calls appearing in the source code for the purpose of maintainability analysis. The purpose of recursive complexity is to fulfill the gap in complexity and maintainability measurements. Intention of this paper is to provoke the discussion on the needs in the field of maintainability analysis regarding complexity measures. Therefore only the basic concepts of the new metric are discussed.

We showed our work on modeling turbine blade crack detection in Sonic Infrared (IR) Imaging with a method of creating flat crack surface in finite element analysis (FEA) in last year's QNDE paper. This modeling has been carried out continuously as part of model-assisted study on crack detection in aircraft engine turbine blades. We have presented that Sonic IR Imaging NDE is a viable method to detect defects in various structures. It combines ultrasound excitation for frictional heating in defects and infrared imaging to sense this heating, and thus to identify the defects. It is a fast wide-area imaging technology. It only takes a second to image a large area of a target sample. When an aircraft is in flight, the turbine engine blades operate under high temperature and high cyclic stresses. Thus, fatigue cracks can form after many hours of operation. Sonic IR Imaging can be used to detect such cracks. However, we still need to better understand contributions of parameters/factors in the crack detection process with Sonic IR Imaging. FEA modeling can help us to reveal certain aspects through the data it produces where experimental work cannot achieve. Upon the model we presented last year, a two-step simulation process was designed to simulate the important aspects in our experiments. These include a newly designed model for the ultrasound transducer which delivers mechanical energy to the sample and the implementation of static force while engaging the transducer to the sample. In this paper, we present the ideas and the results from the new model.

Simulation has been introduced to solve problems in the form of systems. By using this technique the following two problems can be overcome. First, a problem that has an analytical solution but the cost of running an experiment to solve is high in terms of money and lives. Second, a problem exists but has no analytical solution. In the field of statistical inference the second problem is often encountered. With the advent of high-speed computing devices, a statistician can now use resampling techniques such as the bootstrap and permutations to form pseudo sampling distribution that will lead to the solution of the problem that cannot be solved analytically. This paper discusses how a Monte Carlo simulation was and still being used to verify the analytical solution in inference. This paper also discusses the resampling techniques as simulation techniques. The misunderstandings about these two techniques are examined. The successful usages of both techniques are also explained.

This paper was conducted to determine the optimal travel routes for self-drive tourism based on the allocation of time and expense by maximizing the amount of attraction scores assigned to each city involved. Self-drive tourism represents a type of tourism where tourists hire or travel by their own vehicle. It only involves a tourist destination which can be linked with a network of roads. Normally, the traveling salesman problem (TSP) and multiple traveling salesman problems (MTSP) method were used in the minimization problem such as determination the shortest time or distance traveled. This paper involved an alternative approach for maximization method which is maximize the attraction scores and tested on tourism data for ten cities in Kedah. A set of priority scores are used to set the attraction score at each city. The classical approach of the orienteering problem was used to determine the optimal travel route. This approach is extended to the team orienteering problem and the two methods were compared. These two models have been solved by using LINGO12.0 software. The results indicate that the model involving the team orienteering problem provides a more appropriate solution compared to the orienteering problem model.

The nucleosynthesis of 31P in stars of 30 M⊙ model with solar metallicity is investigated using the MESA (Modules for Experiments in Stellar Astrophysics) stellar evolution code. Mass loss mechanisms are included in the evolution of the star with no rotation. The mass loss mechanism used is one constructed by MESA. The paper is divided into two parts. The first part deals with the investigations of the main reactions involved in the production and destruction of 31P. The site for the nucleosynthesis of 31P is also suggested. In the second part of the paper we compare the results of our production of 31P to other papers whenever possible and discuss the need to add new reactions to the network. We also explore the possible mechanisms for the distribution of 31P to the galaxy.

To describe the evolution of anisotropy of sheet metals, in terms of both r-values and stresses, the present paper proposes anisotropic hardening models, where the shape of yield surface changes with increasing plastic strain. In this framework of modeling, any types of yield functions are able to be used. The evolution of anisotropy is expressed by updating the yield function as an interpolation between two yield functions defined at two different effective plastic strains. In this paper, two types of interpolation models, i.e., nonlinear interpolation model and piecewise interpolation model are presented. These models are validated by comparing the experimental data on 3003-O aluminum sheet (after Hu, Int J Plasticity 23, 620-639, 2007). To describe the Bauschinger effect, the combined anisotropic-kinematic hardening model is formulated based on Yoshida-Uemori kinematic hardening model.

An optimal Base-Stock inventory policy for Patient and Impatient Customers using finite-horizon models is examined. The Base stock system for Patient and Impatient customers is a different type of inventory policy. In case of the model I, Base stock for Patient customer case is evaluated using the Truncated Exponential Distribution. The model II involves the study of Base-stock inventory policies for Impatient customer. A study on these systems reveals that the Customers wait until the arrival of the next order or the customers leaves the system which leads to lost sale. In both the models demand during the period [0, t] is taken to be a random variable. In this paper, Truncated Exponential Distribution satisfies the Base stock policy for the patient customer as a continuous model. So far the Base stock for Impatient Customers leaded to a discrete case but, in this paper we have modeled this condition into a continuous case. We justify this approach mathematically and also numerically.

Thermal Barrier Coatings (TBC) are used to reduce the working temperature of the high pressure turbine blade metal surface and hence permit engines to operate at higher temperatures/ efficiencies. A sensor TBC is an adaptation of existing TBCs to enhance their functionality, such that they become sensors and allow measurement of component temperatures. The sensing capability is introduced by embedding optically active materials into the TBC and by illuminating these coatings with excitation light phosphorescence can be observed. The phosphorescence carries temperature and structural information about the coating. This paper describes the first ever implementation of a sensor coating system on a full-scale jet engine. The system consists of three main components: industrially manufactured coatings, advanced remote detection optics with large stand-off distances and tailored control and readout software. The majority of coatings were based on yttrium stabilized zirconia doped with Dy and Eu, although other coatings were manufactured, too. Coatings were produced on a production line using atmospheric plasma spraying. An advanced optical system was designed, manufactured and operated permitting scanning of coated components using a wide acceptance angle. Successful measurements were taken from the nozzle guide vanes at the inlet to the turbine section and are reported in the paper.

In this paper, the linear fractional programming problem with interval coefficients in the objective function is considered. The aim of the paper is to show that a parametric approach, which is an iterative procedure, can be utilized to solve such problem. Questions of how to select the best coefficient through the intervals and also selecting the best value of decision variables are answered in this paper. Finally, the proposed method yields to the optimal solution. An example is given to show the efficiency of the method.

This new session at QNDE reflects the growing interest in inspection automation. Our paper describes a newly developed platform that makes the complex NDE automation possible without the need for software programmers. Inspection tasks that are tedious, error-prone or impossible for humans to perform can now be automated using a form of drag and drop visual scripting. Our work attempts to rectify the problem that NDE is not keeping pace with the rest of factory automation. Outside of NDE, robots routinely and autonomously machine parts, assemble components, weld structures and report progress to corporate databases. By contrast, components arriving in the NDT department typically require manual part handling, calibrations and analysis. The automation examples in this paper cover the development of robotic thickness gauging and the use of adaptive contour following on the NRU reactor inspection at Chalk River.

The paper is a part of student cooperation in AKTION project (Austria-Czech). Method of aposteriori error estimation based on weighted averaging to improve initial triangulation to get better solution of the planar elliptic boundary-value problem of second order and numerical illustrations of the method are presented in the paper.

The paper is devoted to VNIIOFI's measurements of thermodynamic temperature of the high temperature fixed points Co-C, Pt-C and Re-C within the scope of the international project coordinated by the Consultative Committee for Thermometry working group 5 "Radiation Thermometry". The melting temperatures of the fixed points were measured by a radiance mode radiation thermometer calibrated against a filter radiometer with known irradiance spectral responsivity via a high temperature black body. This paper describes the facility used for the measurements, the results and estimated uncertainties.

The closed loop thermoshypon is device operate with working fluid phase change principle. It is a simple and reliable device providing heat transfer. This device utilizes the thermodynamic pressure difference and gravitation to circulate working fluid and has extremely high effective thermal conductivity. Usually is used to cooling of electronic components. The paper describes a design and construction of this device. As a working fluid was used fluorinert FC-72. Next the paper deal with dependences measurement of evaporator temperatures on waste heat of the electronic component and their verification by means of a mathematic calculation based on physical phenomena of boiling, condensation and heat transfer.

In a recent paper [On Some Unified Integrals, Advances in Comput. Math. and Its Applications, Vol. 1, No. 3, PP. 151-153 (2012)], the author has evaluated three very interesting integrals involving hypergeometric function in terms of gamma function. In this paper, three new unified integrals involving Fox’s H-function have been evaluated. By specializing the parameters, we can easily obtain a large number of new and known integrals including one obtained earlier by Garg and Mittal. The results established in this paper are simple, interesting, easily established and may be useful.

In this paper, we solve the mixed boundary value problem on bounded multiply connected region by using the method of boundary integral equation. Our approach in this paper is to reformulate the mixed boundary value problem into the form of Riemann-Hilbert problem. The Riemann-Hilbert problem is then solved using a uniquely solvable Fredholm integral equation on the boundary of the region. The kernel of this integral equation is the adjoint generalized Neumann kernel. As an examination of the proposed method, some numerical examples for some different test regions are presented.

In this paper, we applied the Riemann-Liouville approach and the fractional Euler-Lagrange equations in order to obtain the fractional nonlinear dynamic equations involving the classical physical application "Spring-Mass-Dumper System" to both, integer order calculus (IOC) and fractional order calculus (FOC) approaches. After the numerical simulations, we outlined the main results through time histories and the investigation of phase portraits. Thereafter, we believe that the results showed on this paper are pertinent enough to be thoroughly analyzed and maybe it can be the very beginning of a stride towards more realistic and more precise results about fractional-order models when compared to the integer order models in these applications.

In this paper, the sinter cooling process is numerically studied to get the pressure field, velocity field and temperature field when the fluid flows through the porous media by developing a two-dimensional unsteady state computational model. The inlet velocity, layer height, porosity and sinter layer distribution are the main parameters affecting the sinter cooling process. The computational fluid dynamics (CFD) technique is employed to investigate the influences of thermal process of the four parameters. When high temperature sinters are loaded into the sinter cooler from the sintering machine, phenomena of the non-uniform distribution of sinter size takes place which always causes the non-uniform distribution of sinter temperature field and leads to the deformation of the conveyors. In order to get a uniform sinter temperature field, several recommendations are proposed. The results discussed in this paper would be important for the further understanding of the thermal process and transformation of the sinter cooler.

In paper industry, refining the pulp suspension is a costly operation due to the high energy consumed. Nevertheless, this operation is necessary to develop the mechanical properties of the future sheet of paper. Refiners look like hydrodynamic bearing loads, consequently the lubrication theory may be applied. We add to the pioneering work of Rance and Steenberg, the numerical resolution of the Reynolds equation when the local geometry of the bearing load is defined. The validation of this approach was obtained comparing the experimental and theoretical data of the friction coefficient versus the average gap clearance.

This paper identifies the influence variables affecting the resolution of thermometry resistance bridges. The theoretical limit to the resolution is determined by the spectral density of all noise sources, including the thermal noise from the resistors and amplifiers, quantization noise, and the equivalent noise bandwidth. Optimization of resolution is equivalent to minimization of measurement time, which has a Heisenberg-uncertainty-like relationship with equivalent noise bandwidth. Bridge design has a major influence on the compromises between the different noise sources, as well as influencing compromises with respect to measurement time. The paper explains the concept of an ideal averaging filter and illustrates the use of the Allan variance to evaluate the dependence of the resolution on measurement time.

The paper describes different studies linked to extrusion problems encountered during production in the cable industry. Extrusion simulation or rheology analysis can be used to understand the origin of the problems in cable manufacturing and to set up durable industrial solutions by selecting the appropriate compounds, optimizing screw profiles, modifying the geometries of the tooling or adapting the processing conditions. Our investigations based on the COMPUPLAST® Virtual Extrusion Laboratory™ software, have brought large understanding and these investigations are cheaper and faster alternatives to real experiments (trials/errors) when analyzing and optimizing extrusion processes. Three examples are presented in the paper.

This paper presents a numerical study of a low Reynolds number flow around a thick airfoil (Eppler's E863 airfoil) with and without an upper-surface vortex-trapping cavity. The numerical model of flow is constructed using an O-grid computational domain around the airfoil and analyzed using four different turbulence models: namely standard k-e, RNG k-e, SST k-ω and the one-equation Spallart-Almaras (SA). Enhance wall treatment is employed for the two-equation turbulence models with the non-dimensional first cell height y+ at the wall region kept close to 1. The Reynolds number is kept constant at 354000. Results of lift & drag coefficient as well as velocity profiles are presented for four different angles of attack from 0 to 15 deg. The RNG k-e model is found to better predict the flow field and airfoil lift and drag characteristics as compared to the other turbulence models taken into consideration in this paper. The presence of the vortex-trapping cavity midway on the upper-surface of the airfoil is fou...

This paper is a continuation of the paper [1]. Some basic dynamical analysis will be done using the Routh-Hurwitz Criterion. Furthermore, this paper will determine the Hopf bifurcation of the three-dimensional modified Lorenz system by means of the first Lyapunov coefficient. The result shows that Hopf bifurcations occurred at two equilibrium points and are subcritical.