Papers by Keyword: Computer Program

Abstract: The paper deals with the problems and ambiguities that were solved while developing a computer program capable of constructing accurate interaction diagrams. These problems are not satisfactorily described in available literature. Within the paper, amongst other things, the issue of strain of concrete at the ultimate load capacity of a cross-section is also discussed. The developed computer program is available for free and it is possible to use it for the calculation and construction of an interaction diagram of a doubly reinforced rectangular cross-section. More specifically, it provides a subprogram that constructs a simplified point interaction diagram as well as a subprogram that constructs an accurate interaction diagram assuming complex nonlinear stress-strain behaviour of materials.

Abstract: Based on the similar structure theory, we conduct rigorous mathematical derivation and proof for the boundary value problem of a class of differential equation . We put forward a new algorithm------Similar Structure Algorithm to solve such boundary value problems. The similar structure algorithm only includes arithmetic and logical operation, hence it can be oriented towards computer. According to the similar structure algorithm, an example is given to conduct a simulation experiment by the application of computer software at the end of the paper. And we also observe and analysis the variational laws of the laboratory result by changing the coefficient of the boundary condition.

Abstract: Operative and planned rehabilitation of old pipe networks, including water disposal systems, is a relevant objective of modern city. It is especially difficult to make pipeline reconstruction works in large cities with high construction area density, transport moving intensity, also full of multifunctional both underground and above-ground infrastructure. All these factors set a lot of restrictions for open excavation methods of pipelines repair and reconstruction. That is the reason why trenchless technologies are becoming more popular among the engineers. A wide range of trenchless techniques provides people with convenient method of fast and effective reconstruction processes in comparison with durable and inconvenient open excavation. This fact leads to a necessity of creating a strategic planning of pipeline rehabilitation. This article presents how to operate the first step of such strategic planning – choosing the priority pipe section for sewer network renovation. The most convenient way for choosing one specific section from a great range is to use a program package based on mathematical algorithm that takes into account a quantity of different factors. This paper presents such a program created by authors and describes its interface, date input and processing.

Abstract: Distribution networks are an essential part of all water supply systems. Distribution system costs within any water supply scheme may be equal to or greater than 60% of the entire cost of the project. The reliability of supply is much greater in the case of looped networks. The pipe networks have concentrated outflows or uniform outflow along the length of each pipe. In some pipes with variable discharge of a looped distribution network, water velocity could be reversed between its extremities. Thus, it is a water stall point denominated neutral point in which the discharge is null. In this paper a mathematical model for the determination of water stall point location in the pipes with distributed consumption is developed. This model has been implemented in a computer program for PC microsystems. Numerical example will be presented to demonstrate the accuracy and efficiency of the proposed model.

Abstract: The computer program CARD for used to calculate cosmic radiation doses of aviation route is developed by CAUC. In this paper the function, structure and run principle of CARD is presented. for management of radiation protection, according to the flight data of routes the cosmic radiation effective doses of every year received by the flight personnel during 2001 to 2011 were calculated with software CARD. The results obtained that calculated with CARD were compared with the data calculated using the CARI-6 and measured, respectively. The CARD results and CARI6, and measured agree within 10%.

Abstract: In this study, a new computer program developed to determine the colour properties of natural stone products is introduced. The program can scan any digitalised picture of natural stone products and produce several statistical results such as mean, variance, minimum and maximum colour values, skewness and kurtosis values of the colour histogram, energy, contrast, entropy and homogeneity values of the data which may be used to classify the typology and/or quality of natural stone products. As a case study, Orosei limestones (Sardegna, Italy) were used. There are several typologies of Orosei limestones such as Nuvolato (Cloudy), Venato chiaro (Light veined), Venato medio (Medium veined), Venato scuro (Dark veined), Perlato chiaro (Light pearled), Perlato medio (Medium pearled) and Perlato scuro (Dark pearled). The remarkable results produced by the program are presented.

Abstract: The oil pocket of the hydrostatic worktable in the modern heavy numerical control (NC) machine tools is designed under the circumstance that the working load acts equally on the oil pockets. But when the work piece is out of the rotary center of the worktable, the working load acts unequally on the oil pockets, and then the performance indexes for the oil pockets, such as acting force, oil film thickness, hydraulic damping, rated flow, are different. Based on the eccentric working load, under the circumstance that the oil pocket provides the fluid oil with constant pressure and constant flow mode, the coupling relationship between the oil pockets is analyzed, and the expression and the relatively bar graphics are presented. To achieve the machining quality and to prevent against the totally worn-out of the machine tools, it is best to adjust one oil pocket in order to keep the oil film of all oil pockets at the same thickness. While one oil pocket is adjusted, the oil pockets are intercoupling, and then the performance indexes change synchronously. According to the characteristics of the oil pocket in the hydrostatic worktable, the expression on the coupling relationship for the oil pocket is derived, then the performance indexes are analyzed qualitatively and the curves are plotted. The proposed research analyzed qualitatively the coupling relationship on the performance indexes for the constant pressure and the constant flow oil pockets separately in the worktable. It can improve the design efficiency and the accuracy with the help of the computer programs, and provides the reference for the practical engineering.

Abstract: In this paper, a truss model is used for the geometrically nonlinear static analysis of a thin shallow arch subject to snap-through. Thanks to the very simple geometry of a truss, the equilibrium conditions can be easily written and the global stiffness matrix can be easily updated with respect to the deformed structure, within each step of the analysis. A very coarse discretization is applied. For the geometrically nonlinear static analysis, a short computer program has been developed by displacement control of a plane truss model of a structure. This very short, fully documented computer program is applied on the geometrically nonlinear static analysis of a specific thin shallow arch subject to snap-through.

Abstract: To investigate further the bearing capacity of flexural members of GFRP（Glass Fiber Reinforced Polymer）SR(steel-reinforced concrete) under symmetric monotonic loading, a full range nonlinear analysis is made. Flexural capacity computing program of GFRP-Reinforced structures is put out, according to structure reinforcing theory and correlative rules through the finite ribbon method based on flat section assumption. The moment-curvature relative curves and the influence curves of the fiber winding angle and pipe wall thickness to load-deformation are obtained by the computer programming. The test specimen’s flexural capacity increases obviously with the increasing of steel ribs models. The slope of curve decreasing in monotonic loading latterly showed that the ductility of component improves. The changes of concrete strength had little effect on initial stiffness and capacity of GFRP SR concrete.

Abstract: In connection with the 100^th anniversary of Stoney’s equations, some historical remarks are made with respect to the development of these equations. As an example of the extension of Stoney’s equations, a unique algorithm of the layer growing/removing methods is presented for de­termination of residual stresses in isotropic inhomogeneous coated plates. Using a computer pro­gram based on this algorithm, residual stresses are computed in the galvanic steel coating on the copper plate substrate.