Charcoal-based iron- and steel-making is still employed on a large scale in the state of Minas Gerais in Brazil. The industrial use of charcoal reflects the area's natural resource endowment and foreign exchange ...
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Charcoal-based iron- and steel-making is still employed on a large scale in the state of Minas Gerais in Brazil. The industrial use of charcoal reflects the area's natural resource endowment and foreign exchange constraints. However, the increasing demand for charcoal, driven by Brazilian industrial development, is creating a fuelwood supply crisis. The state energy planning agency is evaluating alternative wood supply and demand policy options through the use of LEAP (Long-range Energy Alternatives Planning System), an integrated energy planning model that emphasizes fuelwood issues. LEAP is a microcomputer-based planning tool that has been primarily used in Africa. LEAP users develop "base case" projections of energy supply and demand. These projections account for expected macroeconomic and demographic changes. A fuelwood strategy that involves other approaches in combination with appropriate amounts of reforestation is desirable.
A FORTRAN IV program is presented which determines transition points for data that can be represented by a set of intersecting regression lines. Initial estimates are not required, and no specific spacing of the data ...
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A FORTRAN IV program is presented which determines transition points for data that can be represented by a set of intersecting regression lines. Initial estimates are not required, and no specific spacing of the data is needed. A spline function is used to reduce the large number of computational steps arising from complex linear models while an iterative least squares procedure is used to obtain the final solution. Examples of experimental and artificially generated data are presented along with an F -statistic for differences in slope at the transition point.
The binding of three tritiated opioid ***, D-ala2-D-leu5-enkephalin and ethylketocyclazocine-was subjected to competitionby unlabeled beta-endorphin, dynorphin-(1-13), and various fragments of these peptides, and the ...
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The binding of three tritiated opioid ***, D-ala2-D-leu5-enkephalin and ethylketocyclazocine-was subjected to competitionby unlabeled beta-endorphin, dynorphin-(1-13), and various fragments of these peptides, and the results analyzed by a computer program that we developed in an earlier study [11]. Peptides in both groups bound with highest affinity to sites 1 and 3 in our 4-site model, corresponding to the mu and delta sites of convention classifications, with the dynorphin peptides also interacting with site 2, the kappa site. These results are discussed in relationship to the possible biological roles of these peptides as analgesics or as modulators of analgesia.
A GIS Decision Support System has been developed for the evaluated of Renewable Energy Sources potential and the financial analysis of RE investments. A GIS database with data on wind, topography, urban areas, and spe...
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A GIS Decision Support System has been developed for the evaluated of Renewable Energy Sources potential and the financial analysis of RE investments. A GIS database with data on wind, topography, urban areas, and special activities has been developed and used for the evaluation of theoretical potential through the spatially continuous mapping if Renewable Energy Resources. The available and technological potential are evaluated by the application of availability and technological restrictions. The evaluation of economical potential is perform by a precise estimation of the expected energy output and installation cost. The financial analysis based on the Internal Rate of Return, identifies the financial viability of alternative investments. The evaluation of wind energy potential for the island of Crete, Greece and the financial analysis of a wind park installation are present as a case study. (C) 1998 Elsevier Science Ltd. All rights reserved.
This research presents a unified numerical model for analyzing the performance of concrete-filled stainless-steel tubular (CFSST) stub columns with different cross-sectional shapes. The model converts the cross-sectio...
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This research presents a unified numerical model for analyzing the performance of concrete-filled stainless-steel tubular (CFSST) stub columns with different cross-sectional shapes. The model converts the cross-sections of the CFSST columns with various shapes into an equivalent circular column, and a new concrete constitutive relation is proposed to estimate the compressive strength of confined concrete of CFSST columns with different cross sections. To simulate the axial load-strain curves of CFSST columns, a computer program is used that converts the various cross-sections of CFSST columns into equivalent circular columns. To validate the model, 196 tested columns with various cross-sections gathered from previous literature are used. The unified model proposed is found to be accurately predicting the performance of CFSST columns. The model is then used to investigate the effects of concrete, steel yield stress, and the depth-to-thickness ratio on the different radius ratios and aspect ratios of CFSST columns. A unified design formula is also suggested to calculate the ultimate strength of CFSST columns with various shapes, and the proposed simplified model is shown to provide a more accurate estimation when compared to existing design codes.
Thermal analysis of energy storage in layers of various materials used as a packed bed storage system is presented. It is more economical to minimize insulation costs, to store more energy from the same input conditio...
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Thermal analysis of energy storage in layers of various materials used as a packed bed storage system is presented. It is more economical to minimize insulation costs, to store more energy from the same input conditions, to lengthen the time of charging that the energy could be kept stored with acceptable losses, and to obtain higher storage capacity. These are the focus of this work. A cylindrical bed is formed from three layers of different materials, equal in length, as heat-absorbing media. The bed is charged with flowing hot air in, the axial direction, the hot air representing the heat source. A transient one-dimensional model is used to describe the thermal behavior of the system. The partial differential equations that govern the flow and heat transfer for both the air and the solid, constituting the bed and their boundary conditions, are driven. The numerical solution of two partial differential equations is obtained using the finite difference method through a computer program especially constructed for this purpose. The temperature field for the air and the solid are obtained, and the energy stored inside the bed is computed. A wide range of layers of storage media of different material with different thermal properties is selected. Comparison is made between the present system and packed bed systems using one storing medium. The results show that the bed packed with different layers has higher storage capacity and there is step stratification of the temperature between the material layers. Also, the bed that includes metal material (such as steel) has a maximum storage capacity, and less considerable temperature than other beds, so such a bed can realize the claimed function.
The computer program MIR previously described (R. Bianchi, G.M. Hanozet and *** Simonetta. Comput. Prog. Biomed. 16 (1983) 189) than fits trial rate laws to enzyme and transport steady-state kinetic data by the least-...
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The computer program MIR previously described (R. Bianchi, G.M. Hanozet and *** Simonetta. Comput. Prog. Biomed. 16 (1983) 189) than fits trial rate laws to enzyme and transport steady-state kinetic data by the least-squares method has been enhanced. The new version MIR II is an interactive program and it consists of five major routines and a larger number of smaller program elements to perform the linear (three different functional forms) and non-linear (eleven mathematical models) regression analysis of kinetic data from enzyme and transmembrane transport experiments, also in the presence of inhibitors. Other features of the new program include a set of statistics and test useful for the model building process, for the development of the mathematical model and for its validation and maintenance. An algorithm for fitting a straight line taking into account errors in both x and y is also provided.
In this paper a computer program is developed for the determination of geometrical and material properties of composite thin-walled beams with arbitrary open cross-section and any arbitrary laminate stacking sequence....
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In this paper a computer program is developed for the determination of geometrical and material properties of composite thin-walled beams with arbitrary open cross-section and any arbitrary laminate stacking sequence. Theory of thin-walled composite beams is based on assumptions consistent with the Vlasov's beam theory and classical lamination theory. The program is written in Fortran 77. Some numerical examples are given, with complete information about input and output.
In this paper we investigate the capabilities of the discrete dipole approximation (DDA) to simulate scattering from particles that are much larger than the wavelength of the incident light, and describe an optimized ...
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In this paper we investigate the capabilities of the discrete dipole approximation (DDA) to simulate scattering from particles that are much larger than the wavelength of the incident light, and describe an optimized publicly available DDA computer program that processes the large number of dipoles required for such simulations. Numerical simulations of light scattering by spheres with size parameters x up to 160 and 40 for refractive index m = 1.05 and 2, respectively, are presented and compared with exact results of the Mie theory. Errors of both integral and angle-resolved scattering quantities generally increase with m and show no systematic dependence on x. Computational times increase steeply with both x and m, reaching values of more than 2 weeks on a cluster of 64 processors. The main distinctive feature of the computer program is the ability to parallelize a single DDA simulation over a cluster of computers, which allows it to simulate light scattering by very large particles, like the ones that are considered in this paper. Current limitations and possible ways for improvement are discussed. (c) 2007 Elsevier Ltd. All rights reserved.
The presented program package, Conformational Analysis and Search Tool (CAST) allows the accurate treatment of large and flexible (macro) molecular systems. For the determination of thermally accessible minima CAST of...
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The presented program package, Conformational Analysis and Search Tool (CAST) allows the accurate treatment of large and flexible (macro) molecular systems. For the determination of thermally accessible minima CAST offers the newly developed TabuSearch algorithm, but algorithms such as Monte Carlo (MC), MC with minimization, and molecular dynamics are implemented as well. For the determination of reaction paths, CAST provides the PathOpt, the Nudge Elastic band, and the umbrella sampling approach. Access to free energies is possible through the free energy perturbation approach. Along with a number of standard force fields, a newly developed symmetry-adapted perturbation theory-based force field is included. Semiempirical computations are possible through DFTB- and MOPAC interfaces. For calculations based on density functional theory, a Message Passing Interface (MPI) interface to the Graphics Processing Unit (GPU)-accelerated TeraChem program is available. The program is available on request. (c) 2014 Wiley Periodicals, Inc.
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