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The occurrence of a high temperature change, such as in a fire incident will have an impact on the concrete structure, cracked surface structure, damage/collapse, and discoloration of the concrete. This research is conducted on K300 concrete with a sample of 15 cm x 15 cm x 15 cm cubes. Burning is carried out at temperatures of 250°C, 500°C, 750°C, and 1000°C with a containment time of 2, 4 and 6 hours. The cooling process is carried out by immersion then rested for 24 hours at room temperature. From the results of the research obtained at temperatures of 250°C, 500°C, 750°C, and 1000°C, the decrease in compressive strength are 4.44% -7.41%, 12.59% -22.96%, 56.44% -66.22%, and 76.74% - 100%. At the containment time for 2 hours, 4 hours and 6 hours, the decrease in compressive strength are w = 4.44% - 76.74%, 6.67% -93.70%, and 7.41% - 100%. At temperatures of 250 °C, 500°C, 750°C, and 1000°C, the increase in porosity are 8.09% - 9.57%, 11.79% - 15.50%, 16.98% - 18.46%, and 19.20% - 26.61%. At the containment time for 2 hours, 4 hours, and 6 hours, the increase in porosity are 8.09% - 19.20%, 8.83% - 22.16%, and 9.57% - 26.61%. From this research, it can be seen that the increase in temperature has a greater impact on the decrease in the compressive strength of concrete and the increase in the porosity of concrete compared to the increase in the combustion duration. Through this research, regression equations are generated which can be used to calculate the residual compressive strength at other combustion temperatures.

A Monte Carlo simulation, with the energetics described by the embedded atom method, has been employed to study the physical behaviour of boron atoms during relaxation of the Ni3AlBinfinity grain boundary. It has also been used to calculate not only the peak concentrations of Ni and B and the valley concentration of Al at the grain boundary, but also the dependence of the grain boundary cohesion on the B bulk concentration. During relaxation of impure Ni3Al grain boundaries, we suggest that, as the segregating species, the B atoms either insert into interstices in the grain boundary or substitute Ni atoms. Meanwhile, as the inducing species, they induce Ni atoms to substitute for Al atoms. Calculations show that in the equilibrium, when the B bulk concentration x increases from 0.1 to 0.9, the peak concentration of B increases, the peak concentration of Ni maximizes while the valley concentration of Al minimizes at x = 0.5. The calculations also show the best cohesion of the grain boundary at x = 0.5.

According to the ISO Geometrical Product Specifications (GPS), the establishment and definition of common datum for geometrical components are not fully defined. There are two main limitations of this standard. Firstly: the explications of ISO examples of common datums are not matched with their corresponding definitions, and secondly: a full definition of common datum is missing. This paper suggests a new approach for an enhanced definition and concrete examples of common datum and proposes a holistic methodology for establishment of common datum for each geometrical component. This research is based on the analysis of physical behaviour of geometrical components, orientation constraints and invariance classes of datums. This approach fills the definition gaps of common datum based on ISO GPS, thereby eliminating those deficits. As a result, an improved methodology for a fully functional defined definition of common datum was formulated.

We consider the resonant response of a Gaussian beam passing through a static magnetic field to a high-frequency relic gravitational wave (GW). It is found that under the synchroresonance condition, the first-order perturbative electromagnetic energy fluxes will contain a ``left circular wave'' and a ``right circular wave'' around the symmetrical axis of the Gaussian beam, but the perturbative effects produced by the + and × polarization of the GW have a different physical behaviour. For the high-frequency relic GW with νg = 1010 Hz, h = 10-30, recently expected by the quintessential inflationary models, the corresponding perturbative photon flux passing through the region 10-2 m2 would be expected to be 104 s-1. This is the largest perturbative photon flux we have recently analysed and estimated using the typical laboratory parameters.

We study some of the mathematical properties of quantum networks with Ising-type nearest-neighbour structure. Based on the formal properties the physical behaviour of the network, such as destructive and constructive interference, is discussed.

We consider a Bianchi type II spacetime of Petrov type D representing an imperfect fluid and an incident source-free magnetic field. The physical behaviour of the realistic model is discussed in detail.

This paper describes the major objectives of the LHD divertor experiment which is proposed to produce currentless-steady-state plasmas with high performance and without any current disruption. Since further improvement in confinement is a common and general requirement for fusion research including the LHD project, it is also necessary to develop the edge plasma control techniques and to understand the physical behaviour in the LHD divertor, i.e. the newly developed continuous helical divertor and a local island divertor (LID) concepts. In order to achieve these objectives, there were several key issues in physics and technology, which had to be resolved through careful investigation before the LHD experiment could start. In this paper, we summarize the recent progress of the physics understanding of divertor functions, divertor plasma operation scenarios, and properties of the LHD magnetic field structure in addition to the experimental planning. We also describe the recent result of an LID experiment in the CHS device, which demonstrated the possibility of edge particle and heat control by the LID.

Let be a three-dimensional body with an interior two-dimensional crack . It will be shown that the location and size of the crack is uniquely determined by measurements on the boundary of . Moreover, the physical behaviour of the crack will be identified. Our model is the following. Inside the body, with the exception of the crack, we assume a harmonic potential. A current flux will be implemented on and we measure the voltage potential there.

The aim of this study is not only to calculate the force acting on a dielectric slab and the direction in which this force acts, but also to provide the conceptual tools which allow for a correct interpretation of the phenomenon. The approach that we propose is based on energy considerations and it assumes the common simplifications which are made for such a system in an introductory physics course. Using graphical representations we have analysed the two situations which can be considered: a system at a constant charge and one at a constant potential difference. The differences found in both cases are discussed. The approach that we describe here is relatively simple and accurate, and it could help university level students to achieve a better understanding of the physical phenomena involved in the problem. Resumen. El objeto de este estudio no solo es el calculo de la fuerza que se ejerce sobre una lamina dielectrica y el sentido en que actua esta fuerza, sino tambien proporcionar las herramientas conceptuales necesarias para conseguir una correcta interpretacion del fenomeno. El procedimiento que proponemos esta basado en consideraciones energeticas y asume las simplificaciones tipicas que se tienen en cuenta en un curso de fisica general. Utilizando representaciones graficas, analizamos las dos situaciones que pueden considerarse; sistema con carga constante y con diferencia de potencial constante. Tambien discutimos las diferencias encontradas en ambos casos. El tratamiento que proponemos en este trabajo es relativamente simple y preciso, y podria ayudar a alumnos de un nivel universitario a una mejor comprension de los fenomenos fisicos implicados en el problema.

An incident Dirac pulse impinging on a wedge generates in addition to a reflected Dirac pulse several diffracted waves that reduce to Dirac distributions on the geometrical optic limits of the shadow and of the reflected wave as necessary to assure the continuity of the total field. Moreover since these diffracted waves have rather simple analytical expressions it is easy to foresee their physical behaviour. We discuss successively diffraction of Dirac pulses at perfectly and non-perfectly conducting half-planes and wedges.

The paper deals with locally rotationally symmetric (LRS) cosmological models of Bianchi type II representing clouds of geometrical as well as massive strings. The energy--momentum tensor for such strings as formulated by Letelier is used to construct a massless string cosmological model and some massive string cosmological models for which is a constant. The physical behaviour of these models is also discussed.

The evolution of an inhomogeneous spherically symmetric cosmological model proposed by Modak is analysed assuming a generalized heat transport equation. Analytical solutions are found after adopting reasonable expressions for the coefficient of heat conductivity and relaxation time. In one of the cases the expanding universe geometry tends to a quasi-flat Friedmann--Robertson--Walker one. The physical behaviour of such a universe is analysed together with the energy conditions.

The generalized Brans–Dicke (GBD) cosmology has been studied for four and higher dimensional space-time models with perfect fluid as source term. Solutions have been obtained for different assumptions and their physical behaviour have been investigated.

For multimode systems of deformed oscillators covariant under the actions of the quantum groups SUq(n), SUq(n mod m), GLp,q(n) and GLp,q(n mod m) the number operators are constructed explicitly in terms of the creation and annihilation operators. The relation between the various kinds of deformed oscillator systems, representations of these oscillator algebras in terms of coordinates and deformed derivatives, realizations of classical groups in non-commutative spaces, and some aspects of the physical behaviour of quantum group covariant oscillator systems are also discussed.

Magnetic phase diagrams of disordered Heisenberg antiferromagnets with mixed uniaxial anisotropy are calculated within a local molecular field theory. The phase diagrams numerically obtained for sets of parameters relevant for the system Fe1-xNixCl2 are in very good agreement with recent experimental results. It is demonstrated that by changing the concentration x, or the ratio of the anisotropies, a rich variety in the physical behaviour of these systems can be expected.

A two-dimensional model of a two-phase solid which undergoes a reaction at its surface is used to study the fragmentation of reactive materials in which the marphalagi- CBI hindering of fragment release is considered. Scaling concepts of cluster percolation theory are used to evaluate Monte Carlo data generated from a Simulation of the hindered fragmentation process. By defining a hierarchy of fragmentation objects, different scaling exponents arc computed for each of these objects as measured by the number of sub-objects they contain. In addition, it appears that each of the different measures of object size exhibits optimum scaling at a different critical reactive-phase mas fraction; simulation data indicate that the critical mass fractions follow a trend consistent with expected physical behaviour of the system. In addition, the critical mass fractions reported correspond to 'virtual' criticalities, i.e. the critical points cannot result in actual divergences in size, but rather are properties of the scaling fundion.

Semi-active magnetorheological (SA MR) dampers seem to represent the easiest way to materialize the concept of smart devices for semi-active structural control. SA MR dampers can be utilized as reactive force generators, when the control algorithms adopted to drive the devices are derived in the framework of control theory, or as smart dampers, when the real-time change of their mechanical properties is aimed at providing, at any time, the optimal amount of damping in a structure. The two approaches have different requirements in modelling the SA MR devices. Based on an experimental campaign on two prototype devices manufactured in Europe, the present paper compares the effectiveness of numerical models presented in the literature and analyses the response time and the dissipative capabilities of such devices. © 2012 IOP Publishing Ltd.

The physical properties of colloidal dispersions often depend on the mechanical shear history. The dependency can be explained in terms of shear-induced changes in particulate structures. A full understanding of the physical behaviour requires, therefore, measuring techniques that are able to analyse the varying structure. An instrument is presented which can follow the changing dielectric spectrum at low frequencies under various shear histories. The mechanical requirements of such a device are discussed. The performance of the electronics is verified by means of computer simulation. The application of the instrument is demonstrated for a carbon black dispersion; the evolution of the dielectric spectrum, after cessation of flow, is followed.

For pt. I see ibid, vol.19, p.L923 (1986). The RSOS-3 model is a sequence of two-dimensional solid-on-solid models with integer heights restricted between 1 and r-1 and nearest neighbours differing by 0, 1 or -1. It has an exact solution manifold with four regimes of distinct physical behaviour along which the height probabilities in the bulk of the system can be calculated. Using some results of the previous letter in this series, the authors calculate the height probabilities for two of the regimes. Appropriate order parameters are defined and their critical exponents calculated.

The investigation of the 965 keV transitions of 198Au shows that the same data analysed with the Fermi function taken from NBS tables and that from Dzhelepov and Zyrianova (corrected for finite size) differ by 3% in slope. With a shape factor C(W)=k(1+aW) the coefficient a has been determined to be -0.022+or-0.011 using Bhalla and Rose tables with Buhring's screening correction and the correct end point determined from the proper physical behaviour of the shape factor in the neighbourhood of the end point energy. The use of this coefficient through the PBS method gives alpha 412K=(301+or-3)10-4 in agreement with theory as well as the recent very accurate IEC methods. This means that the disagreement of the PBS method with theory and other accurate methods arises mainly through the occurrence of a shape factor in the electron energy spectrum and the use of the correct shape factor in the PBS method gives good agreement.

The paper describes a method by which a new selenium-sulphur rectifier photoelectric cell may be constructed, and gives the results of the first part of a full investigation of the physical behaviour of these new cells. The results are related to the details of construction of the cell, so as to show how far they support the theories of A. H. Wilson and of Frenkel and Joffe. A number of simple equations expressing the performance of the cell have been deduced.

There is much interest at present in polysilicon in combination with a wide variety of other materials. The physical behaviour, structure and fabrication of polysilicon as well as its applications to a range of novel device structures were discussed at a recent meeting of the Electronics Group of The Institute of Physics.

U Fano and L Fano London: University of Chicago Press 1972 pp xiv + 592 price £6.55 This is a book for physicists written by two well known authors who themselves have a deep intuitive feeling for physical behaviour. As its title suggests it discusses the physical behaviour of atoms and molecules, and it does so in a new and refreshing manner.