Abstract: In 1978, we proposed that Algol-like languages should be constrained so that aliasing between variables and, more generally, interference between commands or procedures would be syntactically detectable in a fail-safe manner. In particular, we proposed syntactic restrictions that prohibited interference between distinct identifiers, while permitting interference between qualifications of the same identifier. However, these restrictions had the unfortunate property that syntactic correctness was not preserved by beta reduction.

Abstract: Aliasing errors in linear feedback shift registers used as multiple-input signature-analysis registers (MISARs) for self-testing networks are investigated analytically. The authors derive the final value for aliasing errors for a MISAR with the same probability of an error on each of the different inputs. They also derive the final value for aliasing with the same register if there are different probability values of an error on each of the different inputs. This analysis assumes that the different inputs are all independent of one another. The analysis is based on the Markov model. In either case, the final value is shown to be 1/2/sup k/ where k is the length of the shift register. >

Abstract: Signature analysis with multiple-input shift registers (MISRs) is often used to realize efficient built-in self-test of digital VLSI circuits. The authors present a statistical theory that explains the dependence of aliasing probability on the main MISR features, such as length and feedback network, and thus makes it possible to prove criteria for the MISR design. The assumption of independent errors at the register inputs is used to model the register behavior as a Markov process, whose equations are then solved to obtain the exact dependence of aliasing probability as a function of test length, input error probabilities, and feedback structure. >

Abstract: Traditional schemes for abstract interpretation-based global analysis of logic programs generally focus on obtaining procedure argument mode and type information. Variable sharing information is often given only the attention needed to preserve the correctness of the analysis. However, such sharing information can be very useful. In particular, it can be used for predicting run-time goal independence, which can eliminate costly run-time checks in and-parallel execution. In this paper, a new algorithm for doing abstract interpretation in logic programs is described which infers the dependencies of the terms bound to program variables with increased precision and at all points in the execution of the program, rather than just at a procedure level. Algorithms are presented for computing abstract entry and success substitutions which extensively keep track of variable aliasing and term dependence information. The algorithms are illustrated with examples.

Abstract: A brief tutorial is given on what aliasing means. Plots of some relevant functions are shown. Some of the conventional wisdom about aliasing is described, and why that wisdom may not be so wise is explained. Aliasing is actually an image processing phenomenon involving the Fourier transform, convolution and the convolution theorem. >

Abstract: An effort is made to validate experimentally predictions on aliasing in signature analysis registers under the independent error model. From the experimental results it appears that the independent error model accurately predicts the probability of aliasing in signature registers. The authors also provide justification for the adoption of a more general asymmetric error model of which the former is a special case; the latter can be used at no extra cost. Among the potential benefits in using the asymmetric error model is the subdivision of faults into classes based on pD and pDbar, the conditional probability, respectively, of the fault-free bit being 1 and the faulty bit being 0 and vice versa, whereby faults in a given class have the same probability of aliasing. Under the independent error model fault classification is based on a single parameter p. Use of an asymmetric model hence provides a better resolution in terms of the classification of faults based on aliasing probability. Experimental results also indicate that considering the asymmetric nature of circuit outputs yields more useful information, especially in the dynamic region of the aliasing curve. >

Abstract: A dual-frequency-set analysis scheme is proposed which reduces aliasing in the harmonic balance simulation of nonlinear microwave circuits without requiring excessive simulation time. The authors investigate the origin of aliasing and present a condition for determining the smallest acceptable transform frequency set which will reduce aliasing. This derivation is for periodic signals, however, the results can be extended to multiple incommensurate input tones if the transform is accomplished by a multidimensional FFT (fast Fourier transform). Results of some dual set analysis (e.g., for a MESFET amplifier) are presented. >

Abstract: The authors consider the aliasing probability in multiple-input data compressors used in self-testing networks. It is shown that a far more general class of linear machines, linear-feedback shift registers can be used for data-compression purposes. The steady-state value of the aliasing probability is independent of the correlation of the data streams at the inputs of the data compressor. The function of these machines is modeled by a Markov process. The aliasing probability is the same as for the well-understood signature analysis registers with a single input. An easy-to-check criterion is given to decide whether a given linear machine falls into this class of multiple-input data compressors. Two special kinds of circuits are analyzed in more detail with respect to their aliasing properties: linear-feedback shift registers with multiple inputs and linear cellular automata. Simulation results show the effect of the next state function on the steady-state value of the aliasing probability and the effect of correlation on the transient. >

Abstract: An interpolation method is described, which automatically handles the case of events with severe spatial aliasing. The method is defined in the context of spatial deconvolution in the f-x domain. The missing traces result from an equation system solved in the least squares sense. The characteristic of the method is that the events present in the input section are interpolated along their true dips, without any attempt to estimate these dips.

Abstract: In addition to the artefacts caused by an insufficient number of projections, the tomographic images based on filtered-backprojection algorithms are also degraded by the aliasing actefacts. Computed tomographs use X-ray linear detector to acquire the set of projections. Those detectors inherently carry out a sampling and a low pass filtering process. In a previous work, we have proposed an oversampling method to reduce the aliasing frequencies produced by the sampled-data nature of the CCD, and allowing a deconvolution technique to decrease the low pass filtering effects. We propose to apply this superresolution technique to solve the aliasing problem of computerized tomographic images.

Abstract: A system is presented to perform perspective spatial transformations at video-rate using a mapping function which can vary at frame rate. The mapping is implemented by two successive applications of a one-dimensional algorithm operating in scan-line order using a framestore to store an intermediate image. A novel one-dimensional filtering algorithm provides a continuous mapping from source to destination co-ordinates, preventing aliasing. These algorithms are implemented using a stream processing architecture, an efficient mechanism for video-rate operations. Emphasis is placed on the design of a novel stream processing architecture which, coupled with an efficient pipelined co-ordinate generation system, provides single-cycle per output pixel performance.

Abstract: The problem of aliasing has been considered for the testing of circuits employing signature analysis as a means of response evaluation. Various alternative schemes for increasing fault-coverage have been proposed. These schemes are based upon modifications of the linear feedback shift register in various ways. Hardware implementations for achieving enhanced fault coverage of various schemes is presented. The ideas are illustrated by an example.

Abstract: CFTP is a software tool designed to aid programmers in hand-parallelizing sequential ANSI Fortran 77 or CFT code. It assists the programmer by providing information about the code which the programmer must have in order to determine where parallel execution is safe and where it is not. CFTP collects information regarding the input code's usage of its variables. In doing so it builds a call graph, and performs intra- and interprocedural def-use, use-def, and aliasing analysis. CFTP makes the results of these different forms of analysis directly available to the user. >

Abstract: PURPOSE: To decrease the total calculation quantity by using values, which is calculated when pixels to be drawn by known segment drawing algorithm are selected, for aliasing removal CONSTITUTION: Instead of area calculation or distance calculation at the time of the determination of a gradation of a pixel, the values calculated to determine pixels which are closest to a real segment are used by known two- gradation segment drawing algorithm even for gradation calculation Consequently, a segment after proper aliasing removal is drawn fast as to multi-gradational raster graphics, and this system is applied to various software handling graphics, thereby increasing the functions of the graphics

Abstract: A PACS terminal contains a film digitizer which reads radiographic images digitally. Aliasing is often generated when the film digitizer reads images acquired on film using an antiscatter grid. Aliasing interferes with CRT diagnosis and therefore must be reduced. This paper clarifies the mechanism by which aliasing is generated and described how it can be reduced to a level acceptable for CRT diagnosis.

Abstract: Traditional schemes for abstract interpretation-based global analysis of logic programs generally focus on obtaining procedure argument mode and type information. Variable sharing information is often given only the attention needed to preserve the correctness of the analysis. However, such sharing information can be very useful. In particular, it can be used for predicting run-time goal independence, which can eliminate costly run-time checks in and-parallel execution. In this paper, a new algorithm for doing abstract interpretation in logic programs is described which infers the dependencies of the terms bound to program variables with increased precision and at all points in the execution of the program, rather than just at a procedure level. Algorithms are presented for computing abstract entry and success substitutions which extensively keep track of variable aliasing and term dependence information. The algorithms are illustrated with examples.

Abstract: The Markov chain model of linear feedback shift-registers (LFSRs) for signature analysis testing is analytically solved to obtain the exact expression of the aliasing error probability as a function of test length, error probability, and the structure of the feedback network. The dependence on feedback configuration is explored in depth, and it is proven that maximum-length LFSRs have the best performances with respect to aliasing, regardless of the particular structure of their feedback network. Simplified expressions of aliasing probability are also derived for use as practical tools to design LFSRs for IC signature analysis testing, and a heuristic criterion is given for the identification of peaks in aliasing probability. >