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Before 1905 Poincare defined Lorentz’s local time by means of a thought experiment in which observers synchronize their watches with light signals. In 1905 Einstein presented a similar thought experiment in his relativity paper. The similarity between Poincare’s and Einstein’s thought experiment is striking. I suggest that Poincare’s thought experiment before 1905 may have indirectly assisted Einstein in formulating the theory that he had already discovered during the seven years of reflections between 1898 and 1905.

This paper reports the results of an experiment performed at the CERN ISR to search for new particles, produced in pp collisions at √s=53 GeV, which decay into two long‐lived hadrons (i.e. π+, π−, K+, K−, p or ?).

In the paper we consider the dynamic elastic oligopolistic market equilibrium problem in presence of production excesses and show the equivalence between the generalized Cournot-Nash principle and a quasi-variational inequality. Moreover, we present existence and regularity results for equilibrium solutions. Finally, we introduce a long term memory in order to take into account the delay effects in the noncooperative market.

We present a quantum‐like model of decision making in games of the Prisoner’s Dilemma type. By this model the brain processes information by using representation of mental states in complex Hilbert space. Driven by the master equation the mental state of a player, say Alice, approaches an equilibrium point in the space of density matrices. By using this equilibrium point Alice determines her mixed (i.e., probabilistic) strategy with respect to Bob. Thus our model is a model of thinking through decoherence of initially pure mental state. Decoherence is induced by interaction with memory and external environment. In this paper we study (numerically) dynamics of quantum entropy of Alice’s state in the process of decision making. Our analysis demonstrates that this dynamics depends nontrivially on the initial state of Alice’s mind on her own actions and her prediction state (for possible actions of Bob.)

For measurement of the water-cut of the fluid in a low production horizontal well, a combined capacitance sensor is designed which is composed of the cylindrical capacitance sensor and the coaxial capacitance sensor. The two sensors are of parallel connnection in the electric circuit. Because of parallel connnection of the two capacitance sensors, the surface area of the combined sensor increases. Thus in the non-stratified flow, the oil bubbles are apt to touch the sensor and its measurement resolution is improved. And in the stratified flow, the cylindrical capacitance which plays a leading role is sensitive to the hight of oil-water interface. The structure of the sensor is introduced in the paper. The electric field simulation is conducted and the sensor response in the oil/water stratified flow and bubble flow are given. Static experiment and dynamic experiment of the sensor are carried out and the response at the different flowrate and water cut is obtained. The results show that the combined capaci...

Real photon beams in the energy region up to several ten MeV provide a good opportunity for experimental studies of astrophysical nucleosynthesis caused by the electromagnetic interactions as well as the weak interactions. In this paper development of real photon sources at low energies is reviewed, and a recent experimental work on the photonuclear reactions of 4He with new‐generation γ‐ray sources by the laser Compton‐scattering method is presented.

Fuel efficiency requirements demand lightweight construction of vehicle body parts. The usage of advanced high strength steels permits a reduction of sheet thickness while still maintaining the overall strength required for crash safety. However, damage, internal defects (voids, inclusions, micro fractures), microstructural defects (varying grain size distribution, precipitates on grain boundaries, anisotropy) and surface defects (micro fractures, grooves) act as a concentration point for stress and consequently as an initiation point for failure both during deep drawing and in service. Considering damage evolution in the design of car body deep drawing processes allows for a further reduction in material usage and therefore body weight. Preliminary research has shown that a modification of load paths in forming processes can help mitigate the effects of damage on the material.This paper investigates the load paths in Nakajima tests of a DP800 dual phase steel to research damage in deep drawing processes. Investigation is done via a finite element model using experimentally validated material data for a DP800 dual phase steel. Numerical simulation allows for the investigation of load paths with respect to stress states, strain rates and temperature evolution, which cannot be easily observed in physical experiments. Stress triaxiality and the Lode parameter are used to describe the stress states. Their evolution during the Nakajima tests serves as an indicator for damage evolution. The large variety of sheet metal forming specific load paths in Nakajima tests allows a comprehensive evaluation of damage for deep drawing. The results of the numerical simulation conducted in this project and further physical experiments will later be used to calibrate a damage model for simulation of deep drawing processes.Fuel efficiency requirements demand lightweight construction of vehicle body parts. The usage of advanced high strength steels permits a reduction of sheet thickness while still maintaining the overall strength required for crash safety. However, damage, internal defects (voids, inclusions, micro fractures), microstructural defects (varying grain size distribution, precipitates on grain boundaries, anisotropy) and surface defects (micro fractures, grooves) act as a concentration point for stress and consequently as an initiation point for failure both during deep drawing and in service. Considering damage evolution in the design of car body deep drawing processes allows for a further reduction in material usage and therefore body weight. Preliminary research has shown that a modification of load paths in forming processes can help mitigate the effects of damage on the material.This paper investigates the load paths in Nakajima tests of a DP800 dual phase steel to research damage in deep drawing processes....

The aim of this paper is to calculate the fine structure of the optical energy levels scheme of BaLiF3:Ni2+ taken into account besides the spin‐orbit interaction, also the spin‐spin, orbit‐orbit and spin‐other‐orbit interactions. The numerical theoretical crystal field parameters were computed using the model exchange charge calculations of crystal field, taking into account the effects of the covalent bond formation between the Ni2+ and F− ions. The Hamiltonian of the BaLiF3:Ni2+ system has been diagonalized in a complete basis set spanned by all wave functions of the 3d8 electron configuration. The comparison of the calculated energy levels with experimental data gives a satisfactory agreement, which confirms the model and used method.

The paper presents the proprietary know-how of the autowave analysis which occur at deformation of solids. Traditional techniques of X-ray diffraction analysis are described to detect main autowave properties, i.e. wave propagation velocity and length.

The ultrasonic reflectivity of a lubricant layer between two solid bodies depends on the ultrasonic frequency, the acoustic properties of the liquid and solid, and the layer thickness. In this paper, ultrasonic reflectivity measurements are used as a method for determining the thickness of lubricating films in bearing systems. An ultrasonic transducer is positioned on the outside of a bearing shell such that the wave is focused on the lubricant film layer. For a particular lubricant film the reflected pulse is processed to give a reflection coefficient spectrum. The lubricant film thickness is then obtained from either the layer stiffness or the resonant frequency. The method has been validated using static fluid wedges and the elastohydrodynamic film formed between a ball sliding on a flat. Film thickness values in the range 50–500 nm were recorded which agreed well with theoretical film formation predictions.

The fan is one of the main noise sources of an aircraft engine. To reduce fan noise and provide liner optimization in the inlet it is necessary to research modal structure of the fan noise. The present paper contains results of acoustic tests on installation for mode generation that consists of 34-channel generator and the inlet updated for mounting of 100 microphones, the experiments were provided in new anechoic chamber of Perm National Research Polytechnic University, the engine with the same inlet was also tested in the open test bench conditions, and results of the fan noise modal structure are presented. For modal structure educting, all 100 channels were synchronously registered in a given frequency range. The measured data were analyzed with PULSE analyzer using fast Fourier transform with a frequency resolution 8..16 Hz. Single modes with numbers from 0 to 35 at frequencies 500; 630; 800; 1000; 1250; 1600 Hz and different combinations of modes at frequencies 1000, 1600, 2000, 2500 Hz were set dur...

In this paper, the results of measurements of nickel coating thickness are presented. Ni coatings were deposited onto zirconium alloy Zr-1Nb and Si wafers by dc magnetron sputtering. The thickness of Ni coatings was measured by scanning electron microscopy (SEM), ball abrasion method and non-destructive X-ray diffraction (XRD) method. The developed technique of determination of coating uniformity by grazing incidence XRD method was shown. The estimation of uniformity of Ni coatings with a thickness from 0.5 to 2 µm was performed. The distribution map of the coating thickness over surface of 20×20 mm was constructed. The deposited coating with higher thickness of 2 µm has 10% deviation of thickness.In this paper, the results of measurements of nickel coating thickness are presented. Ni coatings were deposited onto zirconium alloy Zr-1Nb and Si wafers by dc magnetron sputtering. The thickness of Ni coatings was measured by scanning electron microscopy (SEM), ball abrasion method and non-destructive X-ray diffraction (XRD) method. The developed technique of determination of coating uniformity by grazing incidence XRD method was shown. The estimation of uniformity of Ni coatings with a thickness from 0.5 to 2 µm was performed. The distribution map of the coating thickness over surface of 20×20 mm was constructed. The deposited coating with higher thickness of 2 µm has 10% deviation of thickness.

We present a methodology to evaluate the moments of the Boltzmann collision term, in a general automated way, using the computer algebra software Mathematica. Based on Grad's distribution function with 26-moments, we compute the non-linear production terms for a simple gas and a granular gas, and the linear production terms for a binary mixture of gases. The results can be shown for general interaction potential, but, in this paper, they are given only for hard-sphere interaction potential.

The paper is based on the ionospheric variations in terms of vertical total electron content (VTEC) for the period from January 2012 to December 2013 based on the analysis of dual frequency signals from the Global Positioning System (GPS) satellites recorded at ground stations Surat (21.16°N, 72.78°E Geog.), situated under the northern crest of the equatorial ionization anomaly region (EIA) and other three International GNSS Service (IGS) stations Bangalore (13.02°N, 77.57°E Geog.), Hyderabad (17.25°N, 78.30°E Geog.), and Lucknow (26.91°N, 80.95°E Geog.) in India. We describe the diurnal and seasonal characteristics. It was observed that GPS-TEC reaches its maximum value between 12:00 and 16:00 IST. Further, Seasonal variations of GPS-TEC is categorized into four seasons, i.e., March equinox (February, March, and April), June solstice (May, June, and July), September equinox (August, September, and October) and December solstice (November, December and January). The forenoon rate of production in Lucknow (beyond EIA crest) is faster than Bangalore, Hyderabad and Surat station. It is found that September equinox shows GPS-TEC slightly higher than the March equinox, followed by June solstice and the lowest GPS-TEC are in winter solstice at four stations. The equinoctial asymmetry clearly observed in the current study. Also GPS-TEC shows a semiannual variation.

With the booming in the manufacturing sector of shoe, garments and toy, etc. in pearl region, training the usage of various facilities and design the facility layout become crucial for the success of industry companies. There is evidence that the use of virtual training may provide benefits in improving the effect of learning and reducing risk in the physical work environment. This paper proposed an advanced web‐based training environment that could demonstrate the usage of a CNC machine in terms of working condition and parameters selection. The developed virtual environment could provide training at junior level and advanced level. Junior level training is to explain machining knowledge including safety factors, machine parameters (ex. material, speed, feed rate). Advanced level training enables interactive programming of NG coding and effect simulation. Operation sequence was used to assist the user to choose the appropriate machining condition. Several case studies were also carried out with animation of milling and turning operations.

This paper reports and discusses the thermal and kinetic behaviour of elastomer flow inside an extrusion die. The reaction progress through the runner was modeled by using a particle tracking technique. The aim is to analyze viscous dissipation phenomena to control scorch arisen, improve the rubber compound curing homogeneity and reduce the heating time in the mould using the progress of the induction time. The heat and momentum equations were solved in three dimensions with Ansys Polyflow. A particle tracking technique was set up to calculate the reaction progress. Several simulations were performed to highlight the influence of process parameters and geometry modifications on the rubber compound thermal and cure homogeneity.

We present in this paper some experimental results about the initiation of homogeneous explosives. We show that the process generally adopted for this initiation is not checked at the used level of pressure. According to some previous studies, we propose here an initiation process by hot spots.

Solder paste is the most widely used interconnection material in the electronic assembly process for attaching electronic components/devices directly onto the surface of printed circuit boards, using stencil printing process. This paper evaluates the performance of three different commercially available Sn‐Ag‐Cu solder pastes formulated with different particle size distributions (PSD), metal content and alloy composition. A series of stencil printing tests were carried out using a specially designed stencil of 75 μm thickness and apertures of 300×300 μm2 dimension and 500 μm pitch sizes. Solder paste printing behaviors were found related to attributes such as slumping and surface tension and printing performance was correlated with metal content and PSD. The results of the study should benefit paste manufacturers and SMT assemblers to improve their products and practices.

Nonplanar surface geometries of components are frequently encountered in real ultrasonic inspection situations. When a flexible array is used instead of rigid array transducers to fit the complex surface profile, the locations of array elements should be known to compute the delay time necessary for adaptive beam focusing. An alternative method is to employ the time reversal focusing technique that does not require a prior knowledge about the properties and structures of the specimen and the transducer. In this paper, a time reversal method is applied to simulate beam focusing of flexible arrays and imaging of point-like defects contained in specimens with nonplanar surface geometry. Quantitative comparisons are made for the performance of a number of array techniques in terms of the ability to focus and image five point-like reflectors positioned at regular intervals. The sinusoidal profile array studied here exhibits almost the same image quality as the flat, reference case.

In this paper, an attempt has been made to forecast two major exchange rates USDAUD (US Dolar versus Australian Dolar currency) and USDJPY (US Dolar versus Japanese Yen currency) using Non-Linear Autoregressive (NAR) with monthly period data from January 1975 to April 2014. The data is collected from Bank of England. The ecchange rates forecasting use 3 layer models with input, hidden and output layer. The number of hidden nodes are 2, and 3 for USDAUD and USDJPY respectively. Levernberg-Marquardt (LM) learning algorithm is used to do training. The accuracy result for the experiments showed that Dstat parameter for USDAUD (60.56%) is a bit higher than industry standard accuracy but lower than industry standard accuracy for USDJPY (52.11%). The MSE result is 0.3239 for USDAUD and 7.518 for USDJPY.

Stabilization of an electrostatic flute‐type instability occurring in a simple magnetic mirror by feedback techniques is discussed. In the first part of the paper a diffuse plasma is considered. The effect of varying the locations of the sensing and suppressing systems is found to alter the stability threshold significantly. In the second part a sharp‐boundary plasma is considered and phase shift and frequency response are included in the feedback terms.

In the basic tokamak experiment, the copper shell is a highly‐satisfactory feedback control device. For certain extensions of the tokamak operation — for example, to compression heating — it is, however, convenient to remove the copper shell. External feedback control of the equilibrium position is then a natural substitute. A more complex problem is the feedback stabilization of MHD modes. The interchange instabilities, against which linear magnetic feedback is ineffective, are fortunately stabilized by the minimum‐average‐B property of the toroidal tokamak. Feedback stabilization of a type of thermal instability that results in major‐radius shifts is the principal topic of this paper.

Digital speckle pattern interferometry (DSPI) is a kind of interferometric technique for the measurement of deformation of objects. Temporal phase‐shifting (TPS) technique has been applied for extracting quantitative deformation data from the fringe patterns. Butterworth low‐pass filter based on discrete cosine transform (DCT), a frequency domain filter, has been applied to remove the fringe patterns noise in this study. It is shown that the Butterworth filter is able to remove the fringe patterns noise to the large extent. Theoretical and experimental results on an edge clamped circular aluminum plate subjected to a central concentrated loading for out‐of‐plane displacement measurement are presented in this paper.

A new secure steganography, which is based on Huffman encoding and modified quantized discrete cosine transform (DCT) coefficients, is provided in this paper. Firstly, the cover image is segmented into 8×8 blocks and modified DCT transformation is applied on each block. Huffman encoding is applied to code the secret image before embedding. DCT coefficients are quantized by modified quantization table. Inverse DCT(IDCT) is conducted on each block. All the blocks are combined together and the steg image is finally achieved. The experiment shows that the proposed method is better than DCT and Mahender Singh’s in PSNR and Capacity.