The dependence of luminescence intensity on the reaction conditions on oxide surfaces permits to determine the kinetic mechanism and gas-surface interaction constants. The suggested method was realized as a computer a...
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The dependence of luminescence intensity on the reaction conditions on oxide surfaces permits to determine the kinetic mechanism and gas-surface interaction constants. The suggested method was realized as a computer algorithm. -. .
We have arbitrarily selected a large body of professionally produced code and subjected it to 'stylistic analysis.' It has not been our intention to criticize the code, nor do we expect the statistics derived ...
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We have arbitrarily selected a large body of professionally produced code and subjected it to 'stylistic analysis.' It has not been our intention to criticize the code, nor do we expect the statistics derived to be an assertion of the elegance, or lack thereof, of any of the constituent programs. So many features affect the 'style' of a program-the language, its history, the number of authors, etc.-that we hope, first, to have drawn attention to an area we believe worthy of further discussion and, second, to have presented some tools and techniques that provide a basis for such discussion. [ABSTRACT FROM AUTHOR]
Analysis of the Au 4f ESCA spectra of thin gold films deposited over a graphite base shows that as the separation from the main photoelectron peak, ΔE, increases the background decreases. Conversely, the effect of a ...
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Analysis of the Au 4f ESCA spectra of thin gold films deposited over a graphite base shows that as the separation from the main photoelectron peak, ΔE, increases the background decreases. Conversely, the effect of a contaminant overlayer on solid gold gives rise to a background which increases as ΔE increases. There is, therefore, a considerable variety of background profiles which can be encountered in real samples, which depends markedly on the element, its concentration, and its distribution in the sample. Over the region of the photoelectron line signal itself, the simple integral description which assumes that the background is proportional to the number of electrons of higher kinetic energy is reasonably valid and is suggested for peak area measurement when a nonlinear profile is needed. Direct integration and curve fitting techniques constitute the two main methods of peak area measurement. Simulated Ni 2p spectra are used to compare the effectiveness of the simple integral and linear background profiles for producing the correct peak areas. Although the simple integral profile shows more consistency and is to be preferred in general, certain fortuitous cancellation effects, particularly with nonmonochromatized spectra, make areas using the linear background fairly accurate in some instances. Curve fitting can overcome many of the problems of direct integration resulting from severe peak overlap. Two types of Gaussian/Lorentzian functions with a suitable exponential tailing function, which has a finite area over reasonable integration limits, are discussed with regard to their use in non-linear least-squares curve fitting methods. Also discussed is the usefulness of composite and difference spectra as simpler methods of determining the relative areas of overlapping peaks.
Highlights how the fundamental understanding that can help programmers write correct programs. Information about a problem that requires binary search; Use of principles of program verification in several stages progr...
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Highlights how the fundamental understanding that can help programmers write correct programs. Information about a problem that requires binary search; Use of principles of program verification in several stages program is developed; Assertions about the program state that is invariantly true at the beginning and end of each iteration of the loop; Techniques of program verification.
The problem of computing the variance of a sample ofNdata points {xi} may be difficult for certain data sets, particularly whenNis large and the variance is small. We present a survey of possible algorithms and their ...
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The problem of computing the variance of a sample ofNdata points {xi} may be difficult for certain data sets, particularly whenNis large and the variance is small. We present a survey of possible algorithms and their round-off error bounds, including some new analysis for computations with shifted data. Experimental results confirm these bounds and illustrate the dangers of some algorithms. Specific recommendations are made as to which algorithm should be used in various contexts.
SUMMARY The precision of comparisons between treatments in an incomplete block design with equal block sizes depends only on the concurrence matrix. An algorithm to find a design with a given concurrence matrix is des...
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SUMMARY The precision of comparisons between treatments in an incomplete block design with equal block sizes depends only on the concurrence matrix. An algorithm to find a design with a given concurrence matrix is described. Its usefulness is compared with that of an algorithm due to Jones and Eccleston. [ABSTRACT FROM AUTHOR]
作者：
PARNAS, DLUSN
RES LABCOMP SCI & SYST BRANCHWASHINGTONDC 20375 IBM CORP
FED SYST DIVARMONKNY 10504
A new programming language control structure as well as an improved approach to a formal definition of programming languages are presented. The control structure can replace both iteration and conditional structures. ...
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A new programming language control structure as well as an improved approach to a formal definition of programming languages are presented. The control structure can replace both iteration and conditional structures. Because it is a semantic generalization of those structures, a single statement using the new control structure can implement the functions of loops, conditionals, and also programs that would require several conventional constructs. As a consequence of this increased capability, it is possible to write algorithms that are simpler, more efficient, and more clearly correct than those that can be written with earlier structured-programming control structures. In order to provide a precise definition of the new constructs, a new version of relational semantics, called LD- relations is presented. An algebra of these relations is developed and used to define the meaning of the new constructs. A short discussion of program development and the history of control structures is included. [ABSTRACT FROM AUTHOR]
The increasing difficulties in testing large logic networks have generated the need for designing logic networks for testability. computer algorithms for designing diagnosable metal oxide semiconductor (MOS) networks ...
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The increasing difficulties in testing large logic networks have generated the need for designing logic networks for testability. computer algorithms for designing diagnosable metal oxide semiconductor (MOS) networks with and without fan-in, fan-out constraints were described in previous papers by the authors. In this two-part series, we discuss the testing of these designed networks.
This paper describes the design and implementation of a program testing assistant which aids a programmer in the definition, execution, and modification of test cases during incremental program development. The testin...
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This paper describes the design and implementation of a program testing assistant which aids a programmer in the definition, execution, and modification of test cases during incremental program development. The testing assistant helps in the interactive definition of test cases and executes them automatically when appropriate. It modifies test cases to preserve their usefulness when the program they test undergoes certain types of design Changes. The testing assistant acts as a fully integrated part of the programming environment and cooperates with existing programming tools such as a display editor, compiler, interpreter, and debugger. [ABSTRACT FROM AUTHOR]
Cell sorting and tritiated thymidine autoradiography were used to define the distribution of S phase cells in flow cytometric DNA histograms obtained from exponential mouse lymphoma cells (L5178Y). The numbers of labe...
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Cell sorting and tritiated thymidine autoradiography were used to define the distribution of S phase cells in flow cytometric DNA histograms obtained from exponential mouse lymphoma cells (L5178Y). The numbers of labeled S phase cells, autoradiorgraphically determined from cells sorted at 2-channel intervals in the G 1 /early S and late S/G 2 M regions of the histogram, were compared with the numbers of computed S phase cells in comparable 2-channel intervals as predicted by several computer algorithms used to extract cell cycle phase distributions from DNA histograms. Polynomial and multirectangle algorithms gave computed estimates of total %S in close agreement with the tritiated thymidine labeling index for the cell population, while multi-Gaussian algorithms underestimated %S. Interval autoradiographic and algorithm studies confirmed these results in that no significant differences were found between the autoradiographic S phase distribution and S phase distributions calculated by the polynomial and multirectangle models. However, S phase cells were significantly underestimated in G 1 /early S by a constrained multi-Gaussian model and in both G 1 /early S and late S/G 2 by an unconstrained multi-Gaussian model. For the particular cell line (L5178Y), staining protocol (mithramycin following ethanol fixation) and instrumentation (Coulter TPS-2 cell sorter) used in this study, close agreement between computed %S and tritiated thymidine labeling index was found to be a reliable indicator of an algorithm's success in resolving S phase cells in the G 1 /S and S/G 2 transition regions of the DNA histograms.
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