Showing papers on "Binary number published in 1997"

A discrete binary version of the particle swarm algorithm

Abstract: The particle swarm algorithm adjusts the trajectories of a population of "particles" through a problem space on the basis of information about each particle's previous best performance and the best previous performance of its neighbors. Previous versions of the particle swarm have operated in continuous space, where trajectories are defined as changes in position on some number of dimensions. The paper reports a reworking of the algorithm to operate on discrete binary variables. In the binary version, trajectories are changes in the probability that a coordinate will take on a zero or one value. Examples, applications, and issues are discussed.

Adaptive Precision Floating-Point Arithmetic and Fast Robust Geometric Predicates,

Abstract: Exact computer arithmetic has a variety of uses, including the robust implementation of geometric algorithms. This article has three purposes. The first is to offer fast software-level algorithms for exact addition and multiplication of arbitrary precision floating-point values. The second is to propose a technique for adaptive precision arithmetic that can often speed these algorithms when they are used to perform multiprecision calculations that do not always require exact arithmetic, but must satisfy some error bound. The third is to use these techniques to develop implementations of several common geometric calculations whose required degree of accuracy depends on their inputs. These robust geometric predicates are adaptive; their running time depends on the degree of uncertainty of the result, and is usually small.

Sidelobe reduction in array-pattern synthesis using genetic algorithm

Abstract: A simple and flexible genetic algorithm (GA) for pattern synthesis of antenna array with arbitrary geometric configuration is presented. Unlike conventional GA using binary coding and binary crossover, this approach directly represents the array excitation weighting vectors as complex number chromosomes and uses decimal linear crossover without a crossover site. Compared with conventional GAs, this approach has a few advantages: giving a clearer and simpler representation of the problem, simplifying chromosome construction, and totally avoiding binary encoding and decoding so as to simplify software programming and to reduce CPU time. This method also allows us to impose constraints on phases and magnitudes of complex excitation coefficients for preferable implementation in practice using digital phase shifters and digital attenuators. Successful applications show that the approach can be used as a general tool for pattern synthesis of arbitrary arrays.

Statistics of chaotic binary sequences

Abstract: Statistical properties of binary sequences generated by a class of ergodic maps with some symmetric properties are discussed on the basis of an ensemble-average technique. We give a simple sufficient condition for such a class of maps to produce a fair Bernoulli sequence, that is, a sequence of independent and identically distributed (i.i.d.) binary random variables. This condition is expressed in terms of binary function, which is a generalized version of the Rademacher function for the dyadic map.

Analytical method for blind binary signal separation

Abstract: The blind separation of multiple co-channel binary digital signals using an antenna array involves finding a factorization of a data matrix X into X=AS, where all entries of S are +1 or -1. It is shown that this problem can be solved exactly and noniteratively, via a certain generalized eigenvalue decomposition. As indicated by simulations, the algorithm is robust in the presence of noise. An interesting implication is that certain cluster segmentation problems can be solved using eigenvalue techniques.

PHDD: an efficient graph representation for floating point circuit verification

Abstract: Data structures such as *BMDs, HDDs, and K*BMDs provide compact representations for functions which map Boolean vectors into integer values, but not floating point values. In this paper, we propose a new data structure, called Multiplicative Power Hybrid Decision Diagrams (*PHDDs), to provide a compact representation for functions that map Boolean vectors into integer or floating point values. The size of the graph to represent the IEEE floating point encoding is linear with the word size. The complexity of floating point multiplication grows linearly with the word size. The complexity of floating point addition grows exponentially with the size of the exponent part, but linearly with the size of the mantissa part. We applied *PHDDs to verify integer multipliers and floating point multipliers before the rounding stage, based on a hierarchical verification approach. For integer multipliers, our results are at least 6 times faster than *BMDs. Previous attempts at verifying floating point multipliers required manual intervention. We verified floating point multipliers before the rounding stage automatically.

Low-power FIR digital filters using residue arithmetic

Abstract: This paper demonstrates that residue arithmetic can result in implementation of low-power FIR digital filters. It is shown that, for word-lengths up to 32 bits, the power consumption of residue arithmetic-based FIR filters is dramatically less than two's-complement-based FIR filters. The power reduction is possible since the use of residue arithmetic transforms the filtering problem into multiple smaller word-length filters for various moduli which are operated in parallel. These compact filters can be operated with a lower supply voltage for a specified sample speed, thus obtaining decreased power consumption compared to binary. Power reduction factors for residue arithmetic implementation become increasingly favorable as the system word-length is increased.

Critical end point behavior in a binary fluid mixture

Abstract: We consider the liquid-gas phase boundary in a binary fluid mixture near its critical end point. Using general scaling arguments we show that the diameter of the liquid-gas coexistence curve exhibits singular behaviour as the critical end point is approached. This prediction is tested by means of extensive Monte-Carlo simulations of a symmetrical Lennard-Jones binary mixture within the grand canonical ensemble. The simulation results show clear evidence for the proposed singularity, as well as confirming a previously predicted singularity in the coexistence chemical potential [Fisher and Upton, Phys. Rev. Lett. 65, 2402 (1990)]. The results suggest that the observed singularities, particularly that in the coexistence diameter, should also be detectable experimentally.

Method and apparatus for recording and reading date data having coexisting formats

Abstract: Years past 1999 are stored as binary integers or in other coding schemes not reserved by ASCII or EBCDIC in fields previously reserved for representations of years as two decimal digits. The binary integers occupy ranges of values for the fields which are not used by an integer value corresponding to any possible combination of two decimal digits from 00 to 99. Data written in binary format and data written in a conventional format such as ASCII can be distinguished in various ways, such as by determining whether the year datum has a binary integer value falling inside or outside the range for possible ASCII combinations of two digits, or testing the bit having a place value of 4,096. If this bit is tested, it will always be on (one) for data written in ASCII and off (zero) for all binary integer values from zero through 4,095. In this way, data using integer-encoded years and years represented by the last two decimal digits will be able to coexist for at least ten thousand years.

Inverse Kinematics of Binary Manipulators Using a Continuum Model

Abstract: Binary actuators have only two discrete states, both of which are stable without feedback As a result, manipulators with binary actuators have a finite number of states The major benefits of binary actuation are that extensive feedback control is not required, reliability and task repeatability are very high, and two-state actuators are generally very inexpensive, resulting in low cost robotic mechanisms These manipulators have great potential for use in both the manufacturing and service sectors, where the cost of high performance robotic manipulators is often difficult to justify The most difficult challenge with a binary manipulator is to achieve relatively continuous end-effector trajectories given the discrete nature of binary actuation Since the number of configurations attainable by binary manipulators grows exponentially in the number of actuated degrees of freedom, calculation of inverse kinematics by direct enumeration of joint states and calculation of forward kinematics is not feasible in the highly actuated case This paper presents an efficient method for performing binary manipulator inverse kinematics and trajectory planning based on having the binary manipulator shape adhere closely to a time-varying curve In this way the configuration of the arm does not exhibit drastic changes as the end effector follows a discrete trajectory

Dependent Sets of Constant Weight Binary Vectors

Abstract: We determine lower bounds for the number of random binary vectors, chosen uniformly from vectors of weight k, needed to obtain a dependent set.

General cardinality genetic algorithms

Abstract: A complete generalization of the Vose genetic algorithm model from the binary to higher cardinality case is provided. Boolean AND and EXCLUSIVE-OR operators are replaced by multiplication and addition over rings of integers. Walsh matrices are generalized with finite Fourier transforms for higher cardinality usage. Comparison of results to the binary case are provided.

Binary odd-periodic complementary sequences

Abstract: A pair of binary sequences is called complementary if the sum of their aperiodic autocorrelation functions is zero except for zero shift Such sequences are known for relatively few lengths This correspondence therefore introduces pairs of binary odd-periodic complementary sequences, which can be constructed using q-ary m-sequences for many more lengths

Method, apparatus and computer programmed product for binary re-optimization using a high level language compiler

Abstract: Apparatus, methods and computer program products are disclosed for a high level language compiler that includes a binary re-optimization capability. This re-optimization capability inputs a binary executable and outputs a binary module optimized for a target computer system. The binary module can be linked to create an optimized binary executable. This capability is provided by adding a front end segment to the compiler that reads the binary executable and creates an intermediate representation of the binary executable. This intermediate representation is normalized to remove prior optimization artifacts and to virtualize register usage. The intermediate representation is then optimized for a target computer system resulting in a binary module that can be linked to make a binary executable that is optimized for the target computer.

Perfect binary space partitions

Abstract: A binary space partition is a recursive partitioning of a configuration of objects by hyperplanes until all objects are separated. A binary space partition is called perfect if none of the objects is cut by the hyperplanes used by the binary space partition. We present an algorithm that, given a set S of n non-intersecting line segments in the plane, constructs a perfect binary space partition for S , or decides that no perfect binary space partition exists for S , in O(min( n 2 , n log 3 n + m log n )) time, where m is the number of edges in the visibility graph of S . We also prove that deciding whether a set of segments admits a perfect BSP is 3 sum -hard.

S-unit equations, binary forms and curves of genus 2

Abstract: In this paper a practical algorithm is given to find all binary forms with rational coefficients of given degree with discriminant divisible by a given finite set of rational primes, up to an obvious equivalence relation.

New results on binary space partitions in the plane

Abstract: We prove the existence of linear size binary space partitions for sets of objects in the plane under certain conditions. In particular, we construct linear size binary space partitions for sets of fat objects, for sets of line segments where the ratio between the lengths of the longest and shortest segment is bounded by a constant, and for homothetic objects. For all cases we also show how to turn the existence proofs into efficient algorithms.

UBVRI CCD photometry of the old open cluster NGC 6253

Abstract: We present UBVRI photometry for the old open cluster NGC 6253. From comparison of the observed colour-magnitude diagrams with simulations based on stellar evolutionary models we derive in a self consistent way reddening, distance, and age of the cluster: E(B−V)= 0.23–0.32, (m-M)0 = 10.9±0.1, metallicity roughly double than solar, and age ≃ 3 Gyr. The cluster has a binary sequence, discernible even through the field contamination, suggesting that about 1/3 of the cluster members belong to binary, or multiple, systems.

Object detection with vector quantized binary features

Abstract: This paper presents a new algorithm for detecting objects in images, one of the fundamental tasks of computer vision. The algorithm extends the representational efficiency of eigenimage methods to binary features, which are less sensitive to illumination changes than gray-level values normally used with eigenimages. Binary features (square subtemplates) are automatically chosen on each training image. Using features rather than whole templates makes the algorithm more robust to background clutter and partial occlusions. Instead of representing the features with real-valued eigenvector principle components, we use binary vector quantization to avoid floating point computations. The object is detected in the image using a simple geometric hash table and Hough transform. On a test of 1000 images, the algorithm works on 99.3%. We present a theoretical analysis of the algorithm in terms of the receiver operating characteristic, which consists of the probabilities of detection and false alarm. We verify this analysis with the results of our 1000-image test and we use the analysis as a principled way to select some of the algorithm's important operating parameters.

The Discovery of 8.9 Second Pulsations from the Variable X-Ray Source 2E 0050.1-7247 in the Small Magellanic Cloud

Abstract: During a systematic search for periodic signals in a sample of ROSAT PSPC light curves, we discovered ~8.9 s X-ray pulsations in 2E 0050.1-7247, a variable X-ray source in the Small Magellanic Cloud. The source was detected several times between 1979 and 1993 at luminosity levels ranging from ~5 × 1034 ergs s-1 up to 1.4 × 1036 ergs s-1 with both the Einstein IPC and ROSAT PSPC. The X-ray energy spectrum is consistent with a power-law spectrum that steepens as the source luminosity decreases. We revealed a pronounced Hα activity from at least two B stars in the X-ray error circles. These results strongly suggest that the X-ray pulsar 2E 0050.1-7247 is in a Be-type massive binary.

Efficient exponentiation of a primitive root in GF(2/sup m/)

Abstract: In this paper, exponentiation of a primitive root in GF(2/sup m/) is considered. Signed digit (SD) number representation is used to efficiently represent the exponent and the corresponding algorithms and structures for exponentiation are developed. For primitive multiplications required in exponentiations, extended bidirectional linear feedback shift registers are proposed and used for the cases where the exponent is represented as a binary or a radix-4 SD number. Comparisons are made with other methods on the bases of space, time, and possible power consumption. Since the proposed structures can effectively reduce power and area when implemented in VLSI, they are especially suitable for battery powered portable devices.

Scaled and unscaled residue number system to binary conversion techniques using the core function

Abstract: The paper presents related techniques for converting a residue number system (RNS) number to binary, with and without scaling, that use the core function. The techniques remove the difficulties associated with conversion procedures based on the Chinese remainder theorem and the mixed-radix conversion technique. Two new methods for extracting the core of an RNS number are also presented that employ a parity bit to eliminate ambiguity.

Imaging binary stars by the cross-correlation technique

Abstract: We present in this paper a technique for imaging binary stars from speckle data. This technique is based upon the computation of the cross-correlation between the speckle frames and their square. This may be considered as a simple, easy to implement, complementary computation to the autocorrelation function of Labeyrie's technique for a rapid determination of the position angle of binary systems. Angular separation, absolute position angle and relative photometry of binary stars can be derived from this technique. We show an application to the bright double star ζ Sge observed at the 2 m Telescope Bernard Lyot.

A new instrument to measure the shape of the cornea based on pseudorandom color coding

Abstract: We have developed a prototype instrument providing a new way to measure the shape of the cornea. Our approach exploits properties of pseudorandom binary arrays (PRBAs). Encoded in a colored pattern (stimulus) that is mirrored to the eye, a large PRBA allows for unique identification of unambiguously characterized positions both in stimulus and reflected image. This is used to come to an integral reconstruction of the cornea. It is demonstrated that the new technique contributes to a very robust measurement method.

Multicomponent transport effects in sorbent particles under pressure swing conditions

Abstract: A comprehensive theoretical study of the problem of multicomponent adsorption-desorption in sorbent particles under pressure swing conditions is carried out A rigorous mathematical model is formulated for the process in which the dusty-gas model and the commonly used Fickian model are employed to describe the coupling of the mass fluxes and the partial pressures in the pore space, with or without viscous flow The dusty-gas model is used as a standard against which the performance of the Fickian model is tested Computations are carried out for binary (O 2 -N 2 , CO 2 -H 2 ) and quaternary (CO 2 -H 2 -CH 4 -N 2 ) mixtures It is found that the rigorous model (the one based on the dusty-gas model) predicts faster responses for the partial pressures of the components in the mixture Faster responses are also observed when the viscous flow is accounted for in the transport model, with the effect being considerably stronger in the case of the Fickian model The obtained results are also used to investigate the performance of the Glueckauf linear driving force approximation for multicomponent systems It is concluded that like the Fickian diffusion model on which it is based, this approximation cannot predict, even qualitatively, the dynamic responses of the partial pressures in a multicomponent system

On a Property of Perfect Binary Codes

Abstract: It is proved that any perfect binary (n, 3)-code is uniquely reconstructible from the allocation of its code vertices in the two medium layers of the n-dimensional unit cube. A nontrivial upper bound is obtained for the number of such codes.