We have devised a program that allows computation of the power of F-test, and hence determination of appropriate sample and subsample sizes, in the context of the one-way hierarchical analysis of variance with fixed e...
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We have devised a program that allows computation of the power of F-test, and hence determination of appropriate sample and subsample sizes, in the context of the one-way hierarchical analysis of variance with fixed effects. The power at a fixed alternative is an increasing function of the sample size and of the subsample size. The program makes it easy to obtain the power of F-test for a range of values of sample and subsample sizes, and therefore the appropriate sizes based on a desired power. The program can be used for the ''ordinary'' case of the one-way analysis of variance, as well as for hierarchical analysis of variance with two stages of sampling. Examples are given of the practical use of the program.
Based on the integral equation for the stray magnetic field strength inside a magnetized article, computational relationships have been derived in the form of a matrix equation that is convenient when developing softw...
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Based on the integral equation for the stray magnetic field strength inside a magnetized article, computational relationships have been derived in the form of a matrix equation that is convenient when developing software for modeling the distribution of magnetization in arbitrarily shaped articles with different flaws and for calculating and imaging external magnetic fields of the magnetized article. On this basis, a program has been developed that is most suitable for the case where the article boundaries and flaws can be sufficiently accurately defined on a three-dimensional grid with identical rectangular cells.
In this work, the methods used in pinch design were applied to a heat exchanger network with the aid of an improved problem algorithm table. This table enables one to compose composite and grand composite curves in a ...
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In this work, the methods used in pinch design were applied to a heat exchanger network with the aid of an improved problem algorithm table. This table enables one to compose composite and grand composite curves in a simplified way. A user friendly computer code entitled DarboTEK, compiled by using Visual Basic 3.0, was developed for the design of integrated heat exchanger networks and estimation of related capital costs. Based on the data obtained from the TUPRAS petroleum refinery at Izmit, a retrofit design of heat exchanger networks was accomplished using DarboTEK. An investment of $ 3,576,627 is needed which will be paid back in 1.69 years simply by energy conservation due to heat integration. (C) 2001 Elsevier Science Ltd. All rights reserved.
The calculation of the performance of absorption heat pump cycles or the comparison of different types of machine cannot be done in a reasonable way without considering the first cost of the machine and especially the...
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The calculation of the performance of absorption heat pump cycles or the comparison of different types of machine cannot be done in a reasonable way without considering the first cost of the machine and especially the cost of the heat exchangers, as their area and particularly the distribution of the area between the respective components of the heat pump determine the COP. Therefore it makes sense only to compare machines that are optimized in this respect. A good way to evaluate cycles is to calculate the maximum COP in terms of the total cost of the heat exchangers. For that purpose a computer program was developed for different absorption heat pump cycles with water as refrigerant. The calculation method is simple and thus the result reliable. The program is suitable for evaluating double-lift, single-, double- and some triple-effect cycles, each one with different absorption fluids and with different options, such as different solution flows (parallel, serial), different types of absorber (spray- or falling-film absorber), and different types of generator (pool- or falling-film generator). With this instrument different cycles or similar cycles with different features can be compared. An economically significant estimation of the performance of a cycle working under defined conditions is possible.
The HITRAN 2012 compilation of the real and imaginary refractive indices of the materials in aerosols and cloud particles is reviewed. Additions to HITRAN 2012 focus upon materials that are absorptive (i.e. minerals, ...
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The HITRAN 2012 compilation of the real and imaginary refractive indices of the materials in aerosols and cloud particles is reviewed. Additions to HITRAN 2012 focus upon materials that are absorptive (i.e. minerals, burning vegetation, brown carbon, desert dust, and volcanic ash). The HITRAN-RI program, created to facilitate usage of the indices, is discussed. The HITRAN-RI program inter-compares the indices of different data sets and calculates optical properties (i.e. extinction, scattering, absorption, single scattering albedo, backscattering, and asymmetry parameter) for user specified size distributions and particle types. The instructional component of HITRAN-RI introduces the user to Mie calculations for spheres and coated spheres, and applies various mixing rules by which one calculates the effective indices of a multi-component particle. (C) 2013 Elsevier Ltd. All rights reserved.
A program is described which enables performing of genetic algorithms for the determination of two positive real parameters. These new types of procedures are tested on a software of determination of flame temperature...
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A program is described which enables performing of genetic algorithms for the determination of two positive real parameters. These new types of procedures are tested on a software of determination of flame temperatures previously developed in a fully classic way. The genetic operators used are crossover and mutation. They perform operations on a binary coded form of the parameters. The goal of the present study consists in developing and optimizing a genetic determination of the parameters at a given temperature. We succeed in selecting the general architecture of the procedure and implementing it in our main software of calculation of flame temperature. We have chosen this pyrotechnic field of application because we knew the behaviour of the real parameters, so the debugging operations were easier.
A microcomputer application has been designed to assist in the construction of pole figures using a digital universal microscope stage. The software monitors the stage orientation and switch settings in real time. The...
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A microcomputer application has been designed to assist in the construction of pole figures using a digital universal microscope stage. The software monitors the stage orientation and switch settings in real time. The trend and plunge of the microscope axis is displayed on an equal area (Schmidt) stereonet in a user-defined reference frame. Data may be recorded relative to the sides of the petrographic slide as reference frame. Alternatively, the specimen's field orientation may be restored and orientations may be calculated relative to the north-east-down geographical reference frame. The computer calculates, records, and graphically displays pole orientations. Data for different minerals may be stored in separate files and data from several thin sections may be merged in a single pole figure. Output to a dot matrix or laser printer is supported.
This research develops a dynamic viscoelastic model, a Galerkin based time-domain finite element method, and computer program for simulating layered half-space responses under loading pulses. A combined Houbolt, centr...
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This research develops a dynamic viscoelastic model, a Galerkin based time-domain finite element method, and computer program for simulating layered half-space responses under loading pulses. A combined Houbolt, central finite-difference (FD) and forward FD method is proposed for time discretization of acceleration and velocity to reduce time-step lengths. Compared to existing methods, the developed approach has advantages that it: (1) captures the coupled effects of material viscoelasticity, dynamics and system damping, which fosters understanding structural responses and material deformations: (2) is able to model temperature and space-dependent material properties. The model is implemented and validated for a multilayer pavement-soil structure. (C) 2015 Elsevier Ltd. All rights reserved.
Although vegetative filter strips (VFS) are a common BMP used for runoff sediment control, there is currently no widely accepted objective design criteria available to select optimal construction characteristics (filt...
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Although vegetative filter strips (VFS) are a common BMP used for runoff sediment control, there is currently no widely accepted objective design criteria available to select optimal construction characteristics (filter length, width, slope, vegetation) needed to achieve a desired sediment reduction. A design procedure for VFS using VFSMOD- W is presented. VFSMOD, the main component of VFSMOD-W is afield-scale, mechanistic, storm-based model developed to route the incoming hydrograph and sedigraph from an adjacent field through a VFS and to calculate the resulting outflow, infiltration, and sediment trapping efficiency. A front-end model, UH, was developed and added to VFSMOD-W to generate the necessary source area design inputs for VFSMOD. For each design storm, UH generates a rainfall hyetograph, a runoff hydrograph, and sediment loss from the source area using a combination of the NRCS curve number method, the unit hydrograph, and the modified Universal Soil Loss Equation based on topography, land use, and soil type. With these inputs, a set of response curves, i.e., sediment and runoff reduction vs. filter construction characteristics, can be developed from VFSMOD-W outputs for a given design scenario. To illustrate this procedure, a design case was presented where the goal was to obtain a 75% runoff sediment reduction for conditions similar to those of the North Carolina Piedmont region. In addition to two soil types present in the area, the range of conditions used in the analysis included two design alternatives (one concentrating field runoff in a narrower filter), four design storms with 1 to 10 year return periods, and buffer lengths ranging from 1 to 100 m. For the range of design storms considered, the optimal filter lengths obtained were 1 to 4 m for the sandy clay soil and 8 to 44 m for the clay. The results show that in some cases current environmental regulations pertaining to filter lengths in the area will not be sufficient. This application case c
The experimental loss and flux-density distributions, given in the companion paper for two full-scale transformer core-leg models, are compared with theoretical results obtained by computer. The computer program provi...
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The experimental loss and flux-density distributions, given in the companion paper for two full-scale transformer core-leg models, are compared with theoretical results obtained by computer. The computer program provides a 3-dimensional solution of the leakage flux distribution, both outside and inside the core. The flux penetration into the core leg is calculated using an anisotropic-core model, which gives the loss distribution due to the currents induced in the laminations. The predicted and measured flux-density distributions are in good agreement. Predicted loss distributions are consistent with those obtained from rates of rise of temperature, but measurement difficulties limit the accuracy of the comparison.
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