A modified version of the EUTIT program, called NEUTIT, which accounts for potentiometric titrations in polar non-aqueous or partially aqueous media is developed. The program was applied to the titration data of sever...
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A modified version of the EUTIT program, called NEUTIT, which accounts for potentiometric titrations in polar non-aqueous or partially aqueous media is developed. The program was applied to the titration data of several substances in three mixed solvents. The output of the program gives consistent and unbiased estimations of equivalence volumes and acidity constants. Good agreement between acidity constants evaluated from NEUTIT and the reported literature values is found in all cases. The program utilizes all titration data pairs which may be acquired from an automatic titrator unit.
A computer algorithm to calculate the USLE and RUSLE LS-factors over a two-dimensional landscape is presented. When compared to a manual method, both methods yield broadly similar results in terms of relative erosion ...
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A computer algorithm to calculate the USLE and RUSLE LS-factors over a two-dimensional landscape is presented. When compared to a manual method, both methods yield broadly similar results in terms of relative erosion risk mapping. However there appear to be important differences in absolute values. Although both method-yield similar slope values, the use of the manual method leads to an underestimation of the erosion risk because the effect of flow convergence is not accounted for. The computer procedure has the obvious advantage that it can easily be linked to GIS software. If data on land use and soils are available, specific K, C and P-values can be assigned to each land unit so that predicted soil losses can then be calculated using a simple overlay procedure. The algorithm leaves the user the choice to consider land units as being hydrologically isolated or continuous. A comparison with soil data showed a reasonably good agreement between the predicted erosion risk and the intensity of soil truncation observed in the test area.
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 reliability of the method described in the preceding paper (B. Song and J. Springer, J, Colloid Interface Sci. 183, in press, 1996) for the determination of surface and interfacial tension (IFT) of liquid-fluid sy...
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The reliability of the method described in the preceding paper (B. Song and J. Springer, J, Colloid Interface Sci. 183, in press, 1996) for the determination of surface and interfacial tension (IFT) of liquid-fluid systems from the profile of a pendant drop has been studied experimentally, Influences on the resultant IFT values from factors such as the location of the drop profile and illumination conditions are considered, The reproducibility and accuracy of the measurement method were examined by measuring the time dependence of polyethylene glycol (PEG600)/air and water/air systems and by determining the temperature dependence of the polyethylene glycol (PEG6000)/N-2 and LD (low-density) polyethylene/N-2 systems, The effect of drop vibrations on the accuracy of the method is discussed. (C) 1996 Academic Press, Inc.
A new computer program has been created to separate overlapping exothermic and endothermic DTA (DSC) effects, obtained under non-isothermal conditions, occurring due to simultaneous nucleation and growth or more growt...
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A new computer program has been created to separate overlapping exothermic and endothermic DTA (DSC) effects, obtained under non-isothermal conditions, occurring due to simultaneous nucleation and growth or more growth processes, and also to calculate the kinetic parameters of the processes represented by each peak. A new graphical method for the initialization of the required parameters and the refinement of the initial values by the least squares method is presented. The procedure for the determination of the kinetic parameters from DTA data is demonstrated on a model system and on a kinetic analysis of mullite formation from diphasic gel.
Several theoretical forms of the dependence of the electrode differential capacitance on the electrode potential (capacitance curves) have been examined in the context of their effectiveness in fitting experimental da...
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Several theoretical forms of the dependence of the electrode differential capacitance on the electrode potential (capacitance curves) have been examined in the context of their effectiveness in fitting experimental data. Each curve has been derived from a rigorously defined physical model. The link between the capacitance curve and the model has been clearly indicated. The goodness of fit and the curvature measures of non-linearity (maximum intrinsic and maximum parameter effects non-linearity, defined in the paper) served as a criterion for the acceptance or rejection of a particular curve and the related model. A new computer program that facilitates the fitting is briefly described. This user-interactive program enables non-linear fitting of an arbitrary capacitance curve, provides fitted data, together with residuals and the dependence of surface coverage on the electrode potential, and calculates the standard deviations for the parameter estimates, their Student t values and the matrix of parameter correlation coefficients, Additionally, the program provides Box's bias of the parameters and both maximum intrinsic and maximum parameter effects curvature measures. If required, the program output can be arranged to deliver simultaneously the dependence of surface charge density on electrode potential or surface coverage, the theoretical electrocapillary curves and other related information. The two-dimensional grids of the non-linear least-squares solution locus for some parameters are presented. The quality of fit is demonstrated for a few examples. The two-, three- and four-parameter models considered in this paper were unable to fit the experimental data within accepted experimental errors although they did not show any other extraordinary deficiencies. No definite conclusions were reached regarding the six-parameter models considered. Some of them can fit the data within experimental error but more work is required on reparametrization. Some six-parameter mode
This paper presents an algorithm for computing the K-terminal reliability of undirected networks, i.e. the probability that a given set of vertices in the network are connected, when edges and nodes fail independently...
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This paper presents an algorithm for computing the K-terminal reliability of undirected networks, i.e. the probability that a given set of vertices in the network are connected, when edges and nodes fail independently with known probabilities. This algorithm is based on a decomposition method introduced by Rosenthal. It consists in numbering the vertices of the graph so that the successive boundary sets are as small as possible and in evaluating the probabilities of appropriate classes of boundary sets. We show that for the all terminal reliability problem these classes are the partitions of the boundary sets and we describe them for the general problem. Our computational results are so conclusive that networks much larger than those presented before can now be treated.
作者：
Fagan, TMICU/CCU
VAMC Wilkes-Barre 1111 East End Blvd Wilkes-Barre PA 18711 U.S.A.
Computation of the exact confidence interval for a binomial proportion is tedious and requires iterative computer techniques. A Quickbasic program for the IBM PC computer is described that accomplishes the confidence ...
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Computation of the exact confidence interval for a binomial proportion is tedious and requires iterative computer techniques. A Quickbasic program for the IBM PC computer is described that accomplishes the confidence interval calculation accurately, quickly, and with no limits placed on the confidence level, or the size of the numerator or denominator. If desired, the mid-P confidence interval can be computed. The compiled program takes one second on the IBM PC 386/33 without a math co-processor. Copyright (C) 1996 Elsevier Science Ltd.
A computational strategy for the deconvolution of complex spectra involving scalar multiplet patterns is presented, This approach fits spectra that can be composed of single resonances as well as scalar coupling multi...
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A computational strategy for the deconvolution of complex spectra involving scalar multiplet patterns is presented, This approach fits spectra that can be composed of single resonances as well as scalar coupling multiplets for which resonance frequencies, intensities, and lineshape parameters can be optimized, For multiplets, the coupling constant also is optimized, Any external information about the optimizable parameters can be taken into account as external constraints, A lineshape described by absorptive and dispersive Lorentzian and Gaussian contributions and the baseline with up to 40 Fourier and polynomial terms can likewise be optimized, The effectiveness of the procedure is assessed on the basis of computer simulated deconvolutions of a composite of (1)J(C-13-H-2) multiplets arising from a mixture of all possible C-13-H-2 isotopomers of deuterated L-[3-C-13]lactate generated from cell preparations incubated with D-[1-C-13]glucose in D2O, which was analyzed previously with a manual deconvolution procedure (R. Willem, M. Biesemans, F. Kayser, W. J. Malaisse, Magn. Reson. Med. 31, 259-267 (1994)), The use of constraints is shown to lead to an improvement in the results. The fitting strategies and the importance of the baseline as an origin of bias are discussed.
A computational method based on a corrected grid search algorithm has been developed to help in the conformational analysis of crystalline polymers by X-ray diffraction. The program was designed upon the difficulty of...
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A computational method based on a corrected grid search algorithm has been developed to help in the conformational analysis of crystalline polymers by X-ray diffraction. The program was designed upon the difficulty of taking into account all the molecular arrangements that are initially compatible with the experimental diffraction data of polymers, in particular when these consist of chemical repeating units with a wide accessible conformational space. The strategy presented here has been incorporated into a computer program named GEMOX. First, all the models fitting the experimentally determined axial repeat of the chain and having the helical symmetry known for the polymer are rapidly created by computing their atomic coordinates. Secondly, sterically hindered conformations are discarded using force-field energy criteria. For this, a potential energy function containing both non-bonded and torsional terms has been incorporated in the program. The ability of the method to provide a complete survey of the reasonable models for a given system was tested for three well characterized polymers, all of them displaying a complex conformational behaviour. Copyright (C) 1996 Elsevier Science Ltd.
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