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In this paper behavior of steel shear wall Composited (CSSW) with carbon fiber polymer in different angles have investigated. The present experimental and numerical studies conducted to carry out the effects of fiber polymer, angle of fiber polymer. Results showed that the CFRP enhance the behavior of CSSW. Despite the advantages of CSSW, there are some hardness which is caused the use of CSSW become restricted, as evaluating the shear stiffness and ultimate strength which those parameters will need to design and analysis. Analysis of CSSW, due to their out of plan buckling and post buckling behavior is extremely abstruse. Nonlinear analysis of CSSW is possible with finite element software, but nonlinear geometry and material is difficult and it tacks a long time. According to the problems mentioned representing valid formulas in nonlinear region is quite necessary which the formulas obtained from numerical analysis have suggest in this paper.

The aim of this paper is to study the mechanical capacity improvement in a cold formed steel cross section with thickness of 1 mm regards to a cross section made by means of hot-rolled steel with thickness of 4 mm, respectively. Likewise, the differences are studied in the manufacturing processes used in both profiles, and the particularities of cold formed steel cross section. This paper analyzes temperature, stress and deformations using Element Method DEFORM software. This research has been focused in the study of accumulation points of stress to verify the behavior of the sheet of cold formed steel during the folded process. Stress of the steel cross section has been analyzed during the folded process, showing instant step of simulation. Conclusions show how these points of stress concentration could be an influence during the manufacturing process.

Shipbuilding processes involve highly dangerous manual welding operations. Welding of ship hulls presents a hazardous environment for workers. This paper describes a new robotic system, developed by the SHIPWELD consortium, that moves autonomously on the hull and automatically executes the required welding processes. Specific focus is placed on the trajectory control of such a system and forms the basis for the discussion in this paper. It includes a description of the robotic hardware design as well as some methodology used to establish the torch trajectory control.

Multilayer thin films structures have received wide-spread attention due to their fast response and high efficiency. In this paper, we report the properties of PbSe/ZnSe multilayer thin films prepared by vacuum evaporation technique by sequential deposition of individual compounds. The prominent peak corresponding to (2 0 0) plane was observed in the Xray diffractogram with cubic crystal structure. The size of the crystallites are found to be 8 nm and 14 nm for the three-layer and five-layer films respectively. The absorption edge starts at 430 nm for the three-layer structures while that for the fivelayer film starts at 480 nm. The calculated optical band gaps of the three-layer and five-layer PbSe/ZnSe multilayer films are found to be 1.7 eV and 1.9 eV respectively. The electrical resitivities are found to be 2.8 × 107 Ω-cm for the three-layer film and 1.02 Ω cm for the five-layer film. The various electrical properties of the films such as mobility, carrier concentration and sheet resistance also are discussed in this paper.

The analysis of energy flow is a useful method for understanding a system. This paper focuses on the instantaneous measurement of physical conditions and analysis of energy flow in the Stirling-type pulse tube refrigerator. For measuring physical conditions of the working fluid such as the mass flow rate, the temperature, and the pressure, several cryogenic sensors are installed in the Stirling-type pulse tube refrigerator optimally designed in the operating condition of 60 Hz and 2.5 MPa. The physical conditions of the working fluid in the Stirling-type pulse tube refrigerator are carefully measured as varying the operating frequency and the charging pressure. From the measured results, the enthalpy, the PV work, and the loss are quantified in each location of the PTR and the conversion of energy flows is experimentally confirmed. The results of this paper can be used for understanding the optimal operating condition and modifying correlations of various losses in the Stirling-type pulse tube refrigerato...

A flow structure around a ground vehicle has been studied by many researchers using numerous methods, either computational or experimental. However, no analysis of flow field generated by a car passing under a flyover has been carried out. One of the famous simplified models of a car is the Ahmed body that has been established to investigate the influence of the flow structure on the drag. In this paper, we investigate a flow field around Ahmed body of a single cruising condition as the vehicle passes under a flyover, using a computational method with RANS equation. The main objective of this paper is to evaluate the turbulence kinetic energy and velocity magnitude developed within the wall boundary created by the flyover, to the air flow field that is generated by the Ahmed reference car. It was observed that the simulated airflow passes the vehicle was bounded by the wall of the flyover and consequently changes the pattern of the flow field. Understanding the characteristic of this flow field under a flyover is essential if one wants to maximize the recovery of the dissipated energy which, for example, can be used to power a small vertical-axis wind turbine to produce and store electrical energy for lighting under the flyover.

Probabilistic Evolution Approach (PEA) is a method recently developed for the solution of explicit ODEs. There is now a comprehensive knowledge accumulation for PEA. It is well known that the PEA truncation approximants converge to a unique limit representing the solution of the considered ODE in a finite region of the complex planes of the unknowns. The complement of the union of these regions to entire complex plane(s) is the subject of analytic continuation. In this paper we focus on this issue for the Van der Pol Equation. Paper gives the importance rather to the formalism and conceptuality. True implementations are left to future works.

In a recent paper [1] some questions were posed about fluid and heat flows in a geologically-stratified groundwater aquifer with a small slope, subject to a perpendicular temperature gradient. The strength of shear flows in the direction of the maximum slope and the associated convected heat flux were quantified. This paper continues the discussion, in particular about the stability of such flows and the shape of convective rolls that may form when the critical Rayleigh number is exceeded. The models formulated are for buoyancy-driven fluid flow in long, sloping warmwater aquifers with either smoothly-or discretely-layered structures.

This paper explores the use of a parabolized model for hydrodynamic stability study of a two-dimensional flow with complex swirling motion. The approach for predicting transition to vortex breakdown based on the parabolized stability equations to be discussed in this paper reduces the hydrodynamic stability study on the solution of a two-point linear differential eigenvalue problem. The parallel implementation of the LPSE using spectral collocation technique is considered and the numerical stability of the governing equations is presented. The accuracy and efficiency of the proposed numerical scheme are tested for various values of the involved parameters.

Rutherford cables exhibit two classes of parasitic magnetization both of which can distort the bore-field of an accelerator magnet: (1) a static magnetization ("hysteretic") resulting from intrastrand persistent currents, and (2) a dynamic magnetization produced by interstrand coupling currents passing through interstrand contact resistances (ICR) during field ramping. Interstrand coupling can be controlled by a core placed between the layers of the cable. Stainless steel ribbon (with its associated native oxide coating) is a frequently used core. Recently, however, MgO-paper tapes and woven s-glass ribbons have been suggested as alternative core materials in the interests of improved flexibility and compatibility with the cabling process. Interstrand contact resistances can be extracted from the results of AC loss measurement. Accordingly pickup-coil magnetization measurements of AC loss have been carried out on a group of cables with paper and ribbon cores. This paper reports on the resulting ICR results which it compares to those from uncored and stainless-steel-cored cables; it concludes by comparing the LHC-ramp-rate induced coupling magnetization of a typical cored Nb3Sn Rutherford cable with its transport-current-moderated persistent-current magnetizations at low and high fields.Rutherford cables exhibit two classes of parasitic magnetization both of which can distort the bore-field of an accelerator magnet: (1) a static magnetization ("hysteretic") resulting from intrastrand persistent currents, and (2) a dynamic magnetization produced by interstrand coupling currents passing through interstrand contact resistances (ICR) during field ramping. Interstrand coupling can be controlled by a core placed between the layers of the cable. Stainless steel ribbon (with its associated native oxide coating) is a frequently used core. Recently, however, MgO-paper tapes and woven s-glass ribbons have been suggested as alternative core materials in the interests of improved flexibility and compatibility with the cabling process. Interstrand contact resistances can be extracted from the results of AC loss measurement. Accordingly pickup-coil magnetization measurements of AC loss have been carried out on a group of cables with paper and ribbon cores. This paper reports on the resulting ICR result...

In this paper the Pair of Siblings Paradox introduced by Pereira [1] is extended by considering more than two children and more than one child observed for gender. We follow the same lines of Wechsler et al. [2] that generalizes the three prisoners’ dilemma, introduced by Gardner [3]. This paper’s conjecture is that the Pair of Siblings and the Three Prisoners dilemma are dual paradoxes. Looking at possible likelihoods, the sure (randomized) selection for the former is non informative (informative), the opposite that holds for the latter. This situation is maintained for generalizations. Non informative likelihood here means that prior and posterior are equal.

A prime number is co-prime with all the primes as well. This paper utilizes this fact by generating larger prime numbers based on a set of smaller prime numbers. The prime numbers are ordered and each two consecutive primes are coupled to generate their co-prime number formula extending this process larger prime sequence is established. Will the process help us produce larger prime numbers faster and more efficiently? This paper investigates the described process.

In this paper, a theoretical and experimental study is presented related to light interaction with bulk acoustic waves generated from a surface of piezoelectric LiNbO3 and TeO2 crystals. A paratellurite acousto-optic cell was designed and developed on base of conversion of acoustic modes during a reflection from a tilted surface in the cell. An intrinsic shear acoustic wave was excited along [001] axis in the material by means of two metal electrodes deposited on the (001) crystal facet. After the reflection, the shear wave propagated along [001] axis and then it was converted into the [110] mode with the velocity 617 m/s. A prototype acousto-optic device based on XY-cut of LiNbO3 is also described in the paper. Experimental investigation of the devices proved that the diffraction efficiency about 1% was obtained in the paratellurite crystal and also about 2% in the lithium niobate at 1.0 Watt of driving electric power. In this way, a possibility has been demonstrated of a non-traditional acoustic wave ge...

As is well known investigation of many processes of natural sciences reduce to the solving of initial value problem for integro-differential equations which are one of the priority areas of modern mathematics. To define the exact solution of such problems is not always possible. Therefore the scientists constructed approximate methods for solving them. There are a number of papers devoted to finding approximate solutions of integro-differential equations. Unlike at papers investigated, here the numerical solution of initial value problem for Volterra integro-differential equations by the hybrid methods, constructed concrete methods with the degree p ≤ 6 and suggested algorithm for using them.

In this paper we study a mixed problem for the nonlinear Schrodinger equation that have a nonlinear adding, in which the coefficient is a generalized function. Here is proved a solvability theorem of the considered problem with use of the general solvability theorem of the article [28]. Furthermore here is investigated also the behaviour of the solution of the studied problem. aipproc class produce a paper with the correct layout for AIP Conference Proceedings 8.5in × 11in double column.

Seismic tomography becomes important tool recently for imaging complex subsurface. It is well known that imaging complex rich fault zone is difficult. In this paper, The application of time domain inverse scattering wave tomography to image the complex fault zone would be shown on this paper, especially an efficient time domain inverse scattering tomography and their run in cluster parallel computer which has been developed. This algorithm is purely based on scattering theory through solving Lippmann Schwienger integral by using Born's approximation. In this paper, it is shown the robustness of this algorithm especially in avoiding the inversion trapped in local minimum to reach global minimum. A large data are solved by windowing and blocking technique of memory as well as computation. Parameter of windowing computation is based on shot gather's aperture. This windowing technique reduces memory as well as computation significantly. This parallel algorithm is done by means cluster system of 120 processors from 20 nodes of AMD Phenom II. Benchmarking of this algorithm is done by means Marmoussi model which can be representative of complex rich fault area. It is shown that the proposed method can image clearly the rich fault and complex zone in Marmoussi model even though the initial model is quite far from the true model. Therefore, this method can be as one of solution to image the very complex mode.

The microstructural hot-spot formation mechanism of non-shock HMX-based explosive ignition is still unknown. If recent optical observations made on post-mortem samples have clarified the main mechanisms of deformation at the microstructural scale, the train of each event is hardly tractable. In order to obtain realtime observation at the microscale, the punch test proposed during the 90's by the LANL team has been revisited. A reverse-edge-on impact (REOI) experiment is described in this paper. This new set-up allows (1) a constant speed of the projectile, (2) the use of various target designs, (3) macroscopic observations of the deformation and the ignition and (3) real-time optical observations at the microscale. Some results are detailed in this paper to show the interests of the REOI test configuration.

Measurement technology of muti-parameters in particle two-phase system, which has been paid more attention in recent years, is a great challenge for researchers. However, the parameters of particle two-phase system are showing great importance for further study. Not only the density and concentration but also the particle size distributions of disperse phase in particle two-phase system have been studied in this paper. A novel approach of measuring the density and concentration of particle two-phase system has been developed in this paper, in which the multiple reflection technique is employed to obtain acoustic impedance of the particle two-phase system. Furthermore, the density can be determined by the acoustic impedance combined with the information of sound speed for ultrasonic waves, based on the acoustic theory. As a result, the concentration of particle two-phase system could be achieved by means of a strict derivation from the known densities of the discrete and continuous phase. Experiments have been designed to demonstrate the means with the sample of carborundom (SiC) suspension at the mass concentrations of 14%, 17%, 20%, 25% respectively, in which a group of superb ultrasonic signals (see figure 6, including more than 12 echoes in each one), have been obtained with a high frequency and wide-band ultrasonic transducer (V324-SU, Olympus) at a center frequency of 25MHz. Meanwhile, another wide-band ultrasonic transducer (V312-SU, Olympus) with a lower center frequency (5MHz) is utilized to generate and receive ultrasonic signal, then attenuation spectrum are obtained with the method of pulse echo mode measurement. To extract credible particle size distribution from measured ultrasonic attenuation spectrum, McClement's theoretical model, which is actually a simplified and explicit model for the long wave regime, has been adopted together with BLBL (Bouguer-Lambert-Beer-Law) scattering model. The optimum regularization algorithm is put to use in order to overcome the ill-posed problem and inverse particle size distribution accurately. Experiments were performed to validate the methods and algorithms put forward above for the sample of SiC powder and crystalline silicon cutting liquid, and the results show good agreement with the instrument (OMEC Co, Ltd) based on the principle of Coulter.

This paper discusses the use of pulse echo based ultrasonic testing for the inspection of adhesive bonds between very thick composite plates (thickness greater than 30 mm). Large wind turbine blades use very thick composite plates for its main structural members, and the inspection of adhesive bond-line is very vital. A wide gamut of samples was created by changing the thickness of plate and the adhesive. The influence of experimental parameters such as frequency on measurement is studied in this paper. Two different frequencies are chosen, and the measurement error bars are determined experimentally. T-Ray measurements were used to verify and correct results, and conclusions are made based on the combined results.

The Gompertz distribution is commonly used in biology for modeling fatigue and mortality. This paper studies a class of models proposed by Adham and Walker, featuring a Gompertz type distribution where the dependence structure is modeled by a lognormal distribution, and develops a new multivariate formulation that facilitates several numerical and computational aspects. This paper also implements the FBST, the Full Bayesian Significance Test for pertinent sharp (precise) hypotheses on the lognormal covariance structure. The FBST’s e-value, ev(H), gives the epistemic value of hypothesis, H, or the value of evidence in the observed in support of H.

In this paper, we focus on the inverse problem associated with IFSP: Given a target measure μ, find an IFSP (w,p), such that its invariantmeasure μ is sufficiently close to μ in Monge-Kantorovich distance, i.e., dMK(μ,μ) < e. We extend themoment-basedmethod developed by Forte and Vrscay (1995) along two different directions. First, we search for a set of probabilities pi that not only minimizes the collage error but also maximizes the entropy of the iterated function system. Second, we include an extra term in the minimization process which takes into account the sparsity of the set of probabilities. In our new formulations, the minimization of collage error (for moments) can be understood as amulti-criteria problem: At least three different and conflicting criteriamust be considered, i.e., collage error, entropy and sparsity. In this paper, we employ scalarization to reduce the multi-criteria program to a single-criteria program by combining all objective functions with different trade-off weights. The...

The aim of this paper is to complete the classification of three-dimensional complex Leibniz algebras. The description of isomorphism classes of three-dimensional complex Leibniz algebras has been given by Ayupov and Omirov in 1999. However, we found that this list has a little redundancy. In this paper we apply a method which is more elegant and it gives the precise list of isomorphism classes of these algebras. We compare our list with that of Ayupov-Omirov and show the corrections which should be made.

This paper presents a numerical model and modeling study of gas flow through extremely low permeability unconventional reservoirs. In contrast to conventional reservoirs, gas flow and transport in low-permeability rock is subject ore nonlinear processes, such as stronger Klinkenberg effect, non-Darcy flow, strong interaction of gas molecules with solids, and adsorption. This is because of the small or nano size pores and high heterogeneity of such shale gas or tight gas formations. In this paper, we will discuss the fundamentals of nonlinear gas flow in low-permeability porous and fractured reservoirs.

This paper devoted to a computational prediction of blood flow in a stenotic artery using a suitable mathematical model. The artery was modelled as a rigid two-dimensional tube with three different levels of severity of the disease. In the mathematical model, the blood flow equations were governed by the stream function-vorticity equations. Then the cubic interpolation profile scheme with high order of accuracy was applied to discretise the advection term of the equation. Different cases were considered, where the Reynolds number of the blood flow were varied to predict pulsatile of blood flow. The present paper reports the analysis of flow separation area downstream the stenosed artery and the location and peak wall shear stress values. These findings may contribute for early detection and medical treatments to prevent further development of the disease and rupture of the artery.

This paper is focused on the task of elicitation and structuring of knowledge related to selection of inspection resources. The final goal is to obtain an informal model of knowledge oriented to the inspection planning in coordinate measuring machines. In the first tasks, where knowledge is captured, it is necessary to use tools that make easier the analysis and structuring of knowledge, so that rules of selection can be easily stated to configure the inspection resources. In order to store the knowledge a so-called Onto-Process ontology has been developed. This ontology may be of application to diverse processes in manufacturing engineering. This paper describes the decomposition of the ontology in terms of general units of knowledge and others more specific for selection of sensor assemblies in inspection planning with touch sensors.

The problem of robust preview control for uncertain discrete-time systems is investigated in this paper. According to preview control theory, an LQ optimal preview controller for the corresponding normal system is constructed. Based on the controller and robust control theory, some robust stability criterions of uncertain closed-loop systems were obtained by the method of Lyapunov functions. The main contribution of this paper is that the perturbation bound of the parameter uncertainties has been estimated. At last, an example shows the availability of the criterions.

Pyrolysis is the thermal degradation of carbonaceous solid by heat in the absence of oxygen. The feedstocks, such as biomass or solid wastes are heated to a temperature between 400 and 600°C, without introducing oxygen to support the reaction. The reaction produces three products: gas, pyro-fuel oil and char. This paper presents the techniques of producing pyro-oil from waste tires, as well as investigation of the fuel properties suitable for diesel engine applications. In this study, microwave heating technique is employed to pyrolyse the used rubber tires into pyro-oil. Thermal treatment of as received used rubber tires is carried out in a modified domestic microwave heated fixed bed technology. It has been found that, rubber tires, previously used by various researchers, are poor microwave absorbers. Studies have shown that an appropriate microwave-absorbing material, such as biomass char or activated carbon, could be added to enhance the pyrolysis process; thus producing the pyro-oil. The characteristics of pyro-oil, as well as the effect of microwave absorber on its yield, are briefly described in this paper. The temperature profiles during the microwave heating process are also illustratively emphasized. The study provides a means of converting scrap tires into pyro-oil and pyrolytic carbon black production. The proposed microwave thermal conversion process therefore has the potentials of substantially saving time and energy.

The increases of demand on knowledge-based and production-based market force the growth of higher education. International students' enrollment contributes to economic growth and increase country's income, university reputation and name; promote the competitive of education and training markets. This paper used multilevel analysis to study the international students' enrollment in Malaysia public university. Student's background variables and institution background variables were study in this paper and the relationship among them also been investigated. Result shows that institution type is a significance factor on international students' enrollment in Malaysia public university.

Unconventional gas accounts for more than 40% of U.S. domestic gas production and more than 10% of world output. The amount of resources available is still uncertain and estimates vary to a large degree. In this paper, unconventional gas resources within the United States will be examined. This paper will take a brief look at all types of unconventional gas resources (there have been 6 identified) but will concentrate on shale gas and coal-bed methane, as they are the resources receiving the most attention. This paper will also delve into the technology in unconventional gas production and exploration, including recent innovations in the industry. Finally, environmental concerns unique to unconventional gas production will be addressed. Natural gas refers to naturally occurring hydrocarbons found trapped underground. It occurs as mixtures of hydrocarbons of various molecular weights (methane, butane, etc.) and was formed millions of years ago from fossilized organic matter. Natural gas can be used as a cl...

Additive-free hand sheet paper samples were activated by cold-plasma in the presence of acrylic acid (AAc), acrylamide (AAm), methyl acrylate (MAc) and methyl methacrylate (MMa). The characterisation of the modified substrates showed that there grafting has occurred efficiently, as established by weight gain and FTIR spectroscopy. The contact angle measurement were carried out, as a function of pH and showed that the deposition of a drop of water at the surface of the tested samples formed 55° for unmodified substrate to 87°, for MMa-treated papers, respectively, indicating that the surface has became totally hydrophobic. ATR-FTIR spectroscopy was used to check the grafting efficiency.

The present paper describes the quantitative validation of a finite element (FE) model of the ultrasound beam generated by an air coupled non-contact ultrasound transducer. The model boundary conditions are given by vibration velocities measured by laser vibrometry on the probe membrane. The proposed validation method is based on the comparison between the simulated 3D pressure field and the pressure data measured with interferometric laser tomography technique. The model details and the experimental techniques are described in paper. The analysis of results shows the effectiveness of the proposed approach and the possibility to quantitatively assess and predict the generated acoustic pressure field, with maximum discrepancies in the order of 20% due to uncertainty effects. This step is important for determining in complex problems the real applicability of air-coupled probes and for the simulation of the whole inspection procedure, also when the component is designed, so as to virtually verify its inspectability.

Modern jet-engine turbine blades are cast from single crystals of nickel-based superalloys because of the excellent mechanical properties that these materials exhibit at high temperatures. However, the anisotropic behavior of single crystals causes difficulties when using ultrasound to inspect these components for defects that could potentially initiate in-service. This paper describes the development of a 2D ultrasonic array system for the in situ inspection of these components. The problems associated with the inspection of anisotropic single crystal materials such as the directional dependence of the ultrasonic velocity, beam directivities in anisotropic media and the variation in the crystallographic orientation, are all addressed in this paper. In addition, constraints regarding access to the inspection location within the engine are discussed. Finally, the defect detection sensitivity and sizing capability of the developed system is evaluated.

The plasma nitriding process produces a hard near-surface thin layer of the nitrided material. The thickness of the diffused layer, produced in the course of this process, is between 0.001 and 0.6 mm. The paper presents a diffusion model of plasma nitriding that allows one to predict the material hardness distribution within the near-surface layer as a function of time for a modified nitrogen diffusion coefficient. The temperature dependence of the diffusion coefficient are considered in the paper. Hence, the model involves the reaction rates of nitrides formation. The one-dimensional transient diffusion model is then applied to a thin nitride layer. The solution thus obtained is compared with experimental data for a decrease of hardness as a function of depth and time, until the core hardness is reached. Published version

In order to safely work with explosives, their sensitivity to external stimuli needs to be characterized. The Bruceton method for evaluating explosives sensitivity results has been used effectively for over six decades. This has included the skid test on the large scale, and the friction and drop weight impact tests on the small scale. The result was a 50% probability of reaction, useful for ranking the comparative responses of various explosives in order to make a practical assessment of handling safety. This paper summarizes the limitations of the Bruceton method and introduces the efficacies of the D-optimal test method. A comparison of the two approaches is provided using results for RDX, HMX, and PETN. For this paper, the Los Alamos Type 12 Drop Weight Impact apparatus is used to generate and compare 50% drop heights (H50), or mean probability of reaction, using the Bruceton and D-optimal methods. The results show that the mean obtained by the D-optimal method is not significantly different from the mean obtained by the Bruceton method, alleviating potential concerns about departing from a historical database. The D-optimal method accomplishes this by using a larger step size between consecutive tests to efficiently converge on the 17% and 83% probability points of the distribution. In the presentation we will also discuss details of our historical Bruceton testing for impact and friction sensitivity and how these tests are currently evolving in our facilities.

Embedding a new programming language into an existing one is a widely used technique, because it fastens the development process and gives a part of a language infrastructure for free (e.g. lexical, syntactical analyzers). In this paper we are presenting a new advantage of this development approach regarding to adding testing support for these new languages. Tool support for testing is a crucial point for a newly designed programming language. It could be done in the hard way by creating a testing tool from scratch, or we could try to reuse existing testing tools by extending them with an interface to our new language. The second approach requires less work, and also it fits very well for the embedded approach. The problem is that the creation of such interfaces is not straightforward at all, because the existing testing tools are mostly not designed to be extendable and to be able to deal with new languages. This paper presents an extendable and modular model of a testing framework, in which the most basic design decision was to keep the - previously mentioned - interface creation simple and straightforward. Other important aspects of our model are the test data generation, the oracle problem and the customizability of the whole testing phase.

The Extreme Learning Machine (ELM) algorithm conventionally suffers from the inferior batch training performance. In this paper, a new approach to combine ELM outputs is proposed with a view to further develop a persistent IDS. Specifically, this paper proposes the application of an Extreme Learning Machine based approach to the network-based intrusion detection system (IDSs). Good performance is achieved and preliminary results are reported in this paper.

Ball joint is a rotating and swiveling element that is typically installed at the interface between two parts. In an automobile, the ball joint is the component that connects the control arms to the steering knuckle. The ball joint can also be installed in linkage systems for motion control applications. This paper describes the simulation strategy for a ball joint analysis, considering manufacturing process. Its manufacturing process can be divided into plugging and spinning. Then, the interested responses is selected as the stress distribution generated between its ball and bearing. In this paper, a commercial code of NX DAFUL using an implicit integration method is introduced to calculate the response. In addition, the gap analysis is performed to investigate the fitness, focusing on the response of the displacement of a ball stud. Also, the optimum design is suggested through case studies.

The present paper describes a simple method of nanosized BiFeO3 by the solution combustion synthesis using bismuth and iron nitrates as oxidizers and the combination fuel of citric acid and ammonium hydroxide, with fuel to oxidizer ratio (Ψ = 1) one. The X-ray Diffraction results indicated rhombohedral phase (R3m) with JCPDS data card no: 72-2035. The ferroelectric transition of the sample at 8310C was detected by differential thermal analysis. Thermal analysis was done by Thermal gravimetric-Differential thermal analyzer and obtained results were presented in this paper.

The paper is a tribute to Nicol Peacock and has a focus on interests and developments at Culham Laboratory from ~ 1970 when Nicol led the UKAEA spectroscopy team. The paper charts a little of the evolution of these models and their data through the seventies and eighties on into this century at Culham. The paper concludes with the state of efforts to enable easy, universal access to spectral analysis across the scope of Culham activity, of which it is hoped Nicol would approve.

In any sonar system, suppression of the side lobes results in an increase in main beam to side lobe level (signal to noise) ratio, with a consequence in an increase in detection range and resolution. Traditionally, this undertaking is done as part of the signal processing operation of the array. The overall aim of this paper is to investigate the advantages and disadvantages of implementing various shading functions directly on the radiating surface of the individual elements (transducers) of a line array. In particular, this paper examines the performance of various shading (window) functions, such as rectangular, cosine, triangular, Hamming, and Blackman-Harris, by printing the actual shape of the function on a transmitting multi-element line array. The transducers used are of 1-3 piezocomposite material with acoustic window and operate at 300 kHz with over 100 kHz of bandwidth. The results of the acoustic tests and polar (directivity) responses are presented and compared to theoretical simulations. The...

Applications in superconductivity have become widespread, enabled by advancements in cryogenic engineering. In this paper, the history of cryogenic refrigeration, its delivery, its preservation and the important scientific and engineering advancements in these areas in the last 100 years will be reviewed, beginning with small laboratory dewars to very large scale systems. The key technological advancements in these areas that enabled the development of superconducting applications at temperatures from 4 to 77 K are identified. Included are advancements in the components used up to the present state-of-the-art in refrigeration systems design. Viewpoints as both an equipment supplier and the end-user with regard to the equipment design and operations will be presented. Some of the present and future challenges in these areas will be outlined. Most of the materials in this paper are a collection of the historical materials applicable to these areas of interest.

Electromagnetic flow meters based on the principles of Faraday's laws of induction have been used successfully in many industries. In order to achieve velocity profile measurements in single phase and multiphase flows with non-uniform velocity profiles, a novel Imaging Electromagnetic Flow meter (IEF) has been developed which is described in this paper. The novel electromagnetic flow meter uses a microcontroller as the processing core to achieve the function of driving the uniform magnetic field, acquiring voltage signals with electronic system, matrix inversion calculation and result display. The work undertaken in the paper demonstrates that an imaging electromagnetic flow meter for liquid velocity profile measurement is an instrument that is highly suited for control via a microcontroller.

In the proposed SuperKEKB interaction region (IR) magnet system 40superconducting (SC) correction coils are designed to perform some specific functions withcurrent of about 50 A. To energize these coils, 80 current leads will be mounted in thecryostats where the stringent spatial constraint and the cryogenic operation require acompact and optimum design. We propose a compact unit to integrate 8 helium vaporcooled leads (4 pairs). The 8 leads are made of brass and consist of two structures for thetransported current and helium vapor, which are designed and simulated by finite elementmodel (FEM). This paper will introduce the material selection and structure details. To equalize the temperature profiles of the individual leads under the different currents and helium flows, some copper blocks are placed between leads. In the cold test, the 8 leadswere operated in the nominal mode and responded safely to some transient situation. This paper will present the thermal and electrical comparison between the experimental resultsand numerical calculation.

In this paper we consider combining ontologically demarcated information with Saaty's Analytic Hierarchy Process (AHP) [1] for the multicriterial assessment of offers during contract negotiations. The context for the proposal is provided by the Agents in Grid project (AiG; [2]), which aims at development of an agent-based infrastructure for efficient resource management in the Grid. In the AiG project, software agents representing users can either (1) join a team and earn money, or (2) find a team to execute a job. Moreover, agents form teams, managers of which negotiate with clients and workers terms of potential collaboration. Here, ontologically described contracts (Service Level Agreements) are the results of autonomous multiround negotiations. Therefore, taking into account relatively complex nature of the negotiated contracts, multicriterial assessment of proposals plays a crucial role. The AHP method is based on pairwise comparisons of criteria and relies on the judgement of a panel of experts. It measures how well does an offer serve the objective of a decision maker. In this paper, we propose how the AHP method can be used to assess ontologically described contract proposals.

Excitation and detection of ultrasonic vibrations without physical contact has proven to be of great commercial value. First used to excite the resonant vibration of bar shaped laboratory specimens in the 1930's, it was Bruce Thompson's contributions in 1973-5 that launched their practical application to a wide range of difficult NDE problems. As a fresh PhD, he championed the use of mathematical models for the electromagnetic transduction process in order to guide the design and construction of practical transducers. His early papers presented both theoretical and experimental results that exposed the wide range of wave types that could be generated along with the environmental conditions that could be overcome. Several laboratories around the world established research programs to apply the electromagnetic transducer (EMAT) to specific NDE problems. This paper will summarize those applications made by the authors.

The transition to chaotic phase synchronization for a periodically driven spiral-type chaotic oscillator is known to involve a dense set of saddle-node bifurcations. By following the synchronization transition through the cascade of period-doubling bifurcations in a forced Ro¨ssler system, this paper describes how these saddle-node bifurcations arise and how their characteristic cyclic organisation develops. We identify the cycles that are involved in the various saddle-node bifurcations and describe how the formation of multi-layered resonance cycles in the synchronization domain is related to the torus doubling bifurcations that take place outside this domain. By examining a physiology-based model of the blood flow regulation to the individual functional unit (nephron) of the kidney we demonstrate how a similar bifurcation structure may arise in this system as a response to a periodically varying arterial blood pressure. The paper finally discusses how an alternative transition to chaotic phase synchronization may occur in the mutual synchronization of two chaotically oscillating period-doubling systems.

Numerical modeling of machining is an active research field in manufacturing. Despite of the improvement of computers, 3D modeling has still high computational cost. 2D modeling has been extensively used for decades in the prediction of difficult to measure variables in metal cutting. On the other hand long fiber reinforced composites are extensively used in industry; however the numerical modeling of composite cutting is still poorly developed, and mainly focused on 2D approach. Two dimensional approaches imply some simplifying hypotheses those could influence the results obtained from the analysis. In this paper a comparison between 2D and 3D modeling of both metal and composite orthogonal cutting is presented. The aim of the paper is analyzing the validity of the hypothesis involved in 2D modeling comparing with the results obtained from 3D approach.

25 years after Chernobyl, the Fukushima disaster has changed the perspectives of nuclear power. The disaster has shed a negative light on the independence, reliability and rigor of the national nuclear regulator and plant operator and the usefulness of the international IAEA guidelines on nuclear safety. It has become clear that, in the light of the most severe earthquake in the history of Japan, the plants at Fukushima Daiichi were not adequately protected against tsunamis. Nuclear acceptance has suffered enormously and has changed the perspectives of nuclear energy dramatically in countries that have a very risk-sensitive population, Germany is an example. The paper analyses the reactions in major countries and the expected impact on future deployment of reactors and on R&D activities. On the positive side, the disaster has demonstrated a remarkable robustness of most of the 14 reactors closest to the epicentre of the Tohoku Seaquake although not designed to an event of level 9.0. Public acceptance can only be regained with a rigorous and worldwide approach towards inherent reactor safety and design objectives that limit the impact of severe accidents to the plant itself (like many of the new Gen III reactors). A widespread release of radioactivity and the evacuation (temporary or permanent) of the population up to 30 km around a facility are simply not acceptable. Several countries have announced to request more stringent international standards for reactor safety. The IAEA should take this move forward and intensify and strengthen the different peer review mission schemes. The safety guidelines and peer reviews should in fact become legally binding for IAEA members. The paper gives examples of the new safety features developed over the last 20 years and which yield much safer reactors with lesser burden to the environment under severe accident conditions. The compatibility of these safety systems with the current concepts for fusion-fission hybrids, which have recently been proposed for energy production, is critically reviewed. There are major challenges remaining that are shortly outlined. Scientific/technical achievements that are required in the light of the Fukushima accident are highlighted.

We carried out several experiments in which we used sequences of physics problems to investigate students' ability to apply calculus concepts in physics problems. In this paper, we discuss an experiment which focused specifically on the concept of "area under a curve". We organized group problem solving sessions to teach students the concept of area under a curve using our problem sequences. We combined both a paper-based test and a computer-based test with online hints to assess students' ability to transfer their learning to solve new physics problems. We found that students' strategies for solving physics problems using this concept largely depend on problem type and scenario. Students' prior knowledge of area under a curve from calculus could interfere with their ability to learn a coherent model of using this concept in physics contexts.

The goal of this work is the investigation of the necessary conditions for the possible existence of tumbling in rotational motion of rigid bodies. In a stable spinning satellite, tumbling may occur by sufficient strong action of external impulses, when the conical movement characteristic of the stable attitude is de-characterized. For this purpose a methodology is chosen to simplify the study of rotational motions with great amplitude, for example free bodies in space, allowing an extension of the analysis to non-conservative systems. In the case of a satellite in space, the projection of the angular velocity along the principal axes of inertia must be known, defining completely the initial conditions of motion for stability investigations. In this paper, the coordinate systems are established according to the initial condition in order to allow a simple analytical work on the equations of motion. Also it will be proposed the definition of a parameter, calling it tumbling coefficient, to measure the intensity of the tumbling and the amplitude of the motion when crossing limits of stability in the concept of Lyapunov. Tumbling in the motion of bodies in space is not possible when this coefficient is positive. Magnus Triangle representation will be used to represent the geometry of the body, establishing regions of stability/instability for possible initial conditions of motion. In the study of nonconservative systems for an oblate body, one sufficient condition will be enough to assure damped motion, and this condition is checked for a motion damped by viscous torques. This paper seeks to highlight the physical understanding of the phenomena and the influence of various parameters that are important in the process.