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We present a general procedure for obtaining progressively more accurate functional expressions for the electron self-energy by iterative solution of Hedin's coupled equations. The iterative process starting from Hartree theory, which gives rise to the GW approximation, is continued further, and an explicit formula for the vertex function from the second full cycle is given. Calculated excitation energies for a Hubbard Hamiltonian demonstrate the convergence of the iterative process and provide further strong justification for the GW approximation., Comment: 4 pages including 3 figures, RevTeX

In this paper we describe the first Russian spaceborne single frequency aerosol lidar. This lidar was especially designed for studying the cloud formations and the Earth's surface from space and it is planned now that it will be installed onboard the `Spektr' modulus of the orbiting Russian station `Mir'. The construction of the lidar consists of a transmitter-receiver, electronic system of data acquisition and transmission, and the control keyboard. This lidar has undergone the full cycle of ground tests as a part of the whole modulus `Spektr' and now it is ready for launch.

At present day, pipe mill engineers have to deal with challenging technological problems of heavy-wall and high-strength line pipe manufacturing. Numerical analysis of welded large-diameter pipe manufacturing stages is the most efficient way to solve these problems. Corresponding computational technologies and applied software were developed at Physical & Technical Center. Numerical structural analysis of steel plates at various stages of line pipe manufacturing is performed by the finite element method, accounting for geometric and material nonlinearities. The only thing to be done by the engineer in such analysis is to specify required input parameters. All the further process is software controlled. The discrepancy between the numerical analysis results and measured data in the overwhelming majority cases did not exceed 1%.

We experimentally study the effect of the air gap on conversion efficiency and the spectrum of generated third-harmonic pulses in the dual-tripler broadband third-harmonic generation scheme. The experimental results are in good agreement with predictions that the 4-cm air gap is equivalent to a full cycle of phase mismatch among the three interacting pulses (i.e. the fundamental, second-harmonic and third-harmonic pulse). The experimental results also show that the spectrum of the third-harmonic pulse is sensitive to the air gap. We also point out that the air gap effect can be ignored when the dual-tripler system is located in 1000 Pa atmosphere. These results will guide the design of the broadband third-harmonic generation system in high power lasers.

An equivalent transform method for evaluating the effect of water column mismatch on geoacoustic inversion is presented. This quantitative method is derived from perturbative inverse formulations and gives a quantitative way to evaluate how the water column mismatch error transfers into the bottom inversion results. In this paper, this method is illustrated with two test cases, in which linear and nonlinear internal waves are considered as the cause of the water column mismatch, respectively. In the first case, the range‐averaged geoacoustic inversion errors due to the water column mismatch are largely eliminated after a full cycle of the linear internal wave, and the error pattern repeats with the period of the internal wave. However, in the second case, the errors are accumulated but scaled down with increasing range. Additionally, ignoring the lower‐frequency components of the signal removes its corresponding contribution from the overall errors, and reduces the bottom depth influenced by water column ...

The seismic cycle for the San Francisco Bay region is synthesized by a model combining the pre-and post-1906 seismic histories. The long-term acceleration of seismic release (seismic moment, Benioff strain release, or event count) in the seismic cycle and the shorter-term accelerations preceding the larger earthquakes within that cycle are modeled using an empirical predictive technique, called time-to-failure analysis, in which rate of seismic release is proportional to an inverse power of the remaining time to failure. The exponent of time to failure in the accelerating sequences appears to be scale invariant, and the length of the full cycle is estimated at 269 ± 50 years. The 1989 Loma Prieta earthquake, which is the culmination of the first subcycle in the present long-term seismic cycle, should have been predictable with an uncertainty of 2 years in time and 0.5 in magnitude, although the specific location (at Loma Prieta) was not predictable by this technique. If our model is correct and if the Loma Prieta earthquake is the culmination of a subcycle, the San Francisco Bay region should be entering a relatively long (20–50 years) period of seismic quiescence above magnitude 6. A great earthquake, such as the 1906 San Francisco event, would appear to be more than a century in the future.

Calculation of current and voltage phasors in power system protection and control is based on correlation of the signals with sine/cosine (or similar) functions, assuming data windows which are constant and usually amount to one period of the fundamental frequency. However this method introduces large errors in transient states, which follow changes of the signal amplitude and/or phase. The transient state lasts as long as the window. The transient errors are eliminated, if the correlation procedure utilises variable data windows which increase until they reach the one full cycle of the fundamental frequency and then become constant. This enables a phasor to be calculated within 1/4 cycle after the input signal changed. The algorithm is very fast, quite accurate and computationally efficient.

We relate the number of cycles in a product of transpositions with a full cycle with the nullity of a binary matrix. Our theorem generalizes a theorem of Cohn and Lempel.

The development of a new compliance technique is described. Labeled defusing objections, this technique seeks to remove an individual's excuse for not complying with a request. Two common excuses for not responding to a request were manipulated. Removing only one excuse was not sufficient to induce many individuals to respond. However, removing both led over half of the homeowners to respond positively. In fact, the level of responding when both excuses were eliminated was significantly greater than it was in all other conditions combined. The impact of the defusing objections technique is viewed as a successful application of ‘full-cycle social psychology’ and the overall value of this approach is illustrated by tracing the development of other compliance techniques.

Cycle counting can proceed at real time,except the full cycle counting method. In case of the hysteresis loop counting method and the rain flow counting method also half-cycles are counted. Their calculation is based on the physical dependence between stresses and strains of the examined material. All the ranges forming cycles correspond to the closed loops of stress-strain hysteresis and the ranges forming half-cycles correspond to the open loops of this hysteresis. The hysteresis loop counting method is more effective than the range pair counting method and it is more simple than the rain flow counting method in case of programming at real time.

The present method generates machine-independent uniform random sequences of real numbers in the interval (0.,1.) excluding 1. It uses a set of up to 1024 independent multiplicative congruential generators working with:• modulii which are chosen prime numbers whose values have been fixed according to the positive 31-bit positive integer arithmetic available and in the form of 2.P'+1, where P's are also primes.• multipliers which are selected from one of their corresponding primitive elements as multipliers to achieve each full cycle independently. The "astronomical" maximum periodicity can be considered as infinite: O (10 6021 ) ; it can be adjusted if required by the user in the sequential version RAN01 or statistically reaching the maximum in the improved "stagger" version DAN01. An "acceptable" composite period is estimated to be O (10 189 ) for a set of only 32 of such independent generators: this fact could find a nice application in the realization of efficient hash-functions in smart cards.An implementation in structured FORTRAN 77 shows very good results in terms of statistical proprieties, velocity and periodicity.

One of the desirable properties of a pseudorandom number generator is that the sequence of numbers it generates should have very low autocorrelation for all shifts except for zero shift and those that are multiples of its cycle length. Due to the simple methods of constructing random numbers via modulo arithmetic, the ideal is often not quite fulfilled. The results of this paper were obtained by the simple method of examining the complete correlation structure of several generators of the same type and small cycle length. Once the regularities were discovered, the mathematical relationships were derived which describe the regular behavior for all generators of the same class. As examples, it is shown in this paper that high correlation exists in mixed and multiplicative congruential random number generators and prime moduli Lehmer generators for shifts a fraction of their cycle lengths.

Character theoretic methods and the group algebra of the symmetric group are used to derive properties of the number of permutations, with only p p -cycles, for an arbitrary but fixed p p , which are expressible as the product of a full cycle and a fixed point free involution. This problem has application to single face embeddings of p p -regular graphs on surfaces of given genus.

A classical nova model was evolved through a complete cycle, i.e. accretion leading to outburst, mass loss and again accretion, ending in another outburst, by means of an implicit Lagrangian hydrodynamic code, which included diffusion (concentration, pressure and thermal terms), as well as an extensive nuclear reactions network between 28 isotopes of C, N, O, F, Ne, Na, Mg and Al. The initial model was a 1.25 M⊙ C-O white dwarf (WD) and the accretion rate assumed was 10−11 M⊙/yr. For more details of this calculation, see Prialnik (l986).

A new ultrasonic interferometer for the automatic measurement of transit times is described. Its main advantage is its ability to follow very large changes of the transit time (1–20) and still maintain a resolution of typically 2.5×10−10 sec. The method is based on the phase sensitive detection of multiple echoes, counting of the output signal at the rate of four counts per full cycle, and an additional interpolation.

This paper discusses the design trade-offs for a parallel bit-organized MOS memory. A memory capacity of 40K bits can be achieved using LSI techniques. Memory storage capacity is expandable in both word length and number of words stored. The physical dimensions of the memory should be considerably smaller than those of a comparable core design. Power consumption per bit should likewise be less than that achievable with cores. A full cycle time of 1 us or less can be achieved. Cost per bit should compare very favorably with that of a core design.

The synchronization method was used for a global inspection of the relation between the sunspot “cycle” and the annual means of temperature and precipitation totals of 92 stations, which were distributed over a large part of the earth. Taken globally, a tendency could be found that the temperature “cycle” lags up to a quarter of the full cycle behind the sunspots, whereas the precipitation totals advance the sunspots also up to a quarter of the full cycle. The single stations, however, show wide deviations from this average relation.

The method of Chebyshev optimum linkage design is an iterative method related to Newton's method. It requires as an initial approximation a linkage with a number of precision points. The method was applied to the design of a crank rocker linkage to generate the solar declination. The Chebyshev optimum crank rocker linkage gave a maximum structural error of 7·20 minutes over the full cycle with an output range of 47°.

Simplified methods are given for quickly computing with reasonable accuracy the performance of transmitting tubes in the usual radio-frequency and audio-frequency applications. These applications cover the cases where the current wave shapes within the tube are pulses of current which flow for less than the full cycle. The factors controlling the shape of these pulses are discussed and a simplified analysis of the pulses is presented. The problems of choosing the optimum conditions for a transmitting tube are discussed and the conditions for fully utilizing a tube's capabilities in the different classes of service are presented. These methods are illustrated thoroughly by calculations for a standard transmitting tube.

Targeting a new multiple zero finder, in this paper, we suggest an efficient two-point class of methods, when the multiplicity of the root is known. The theoretical aspects are investigated and show that each member of the contributed class achieves fourth-order convergence by using three functional evaluations per full cycle. We also employ numerical examples to evaluate the accuracy of the proposed methods by comparison with other existing methods. For functions with finitely many real roots in an interval, relatively little literature is known, while in applications, the users wish to find all the real zeros at the same time. Hence, the second aim of this paper will be presented by designing a fourth-order algorithm, based on the developed methods, to find all the real solutions of a nonlinear equation in an interval using the programming package Mathematica 8 .

A common framework for the two concepts of the title is developed to yield an alternative proof to a theorem of Cohn and Lempel relating the number of orbits of a product of a full cycle by disjoint transpositions to the rank over GF (2) of the associated chord-intersection-matrix.

In this paper, we consider our choice of a pseudorandom number generator (PRNG) in the context of running a simulation model for the growth of 3D tissues. This PRNG is the multiplicative linear congruential generator (MLCG) with carefully chosen parameters. We base our selection of this generator on three criteria. They are periodicity, randomness quality, and ease of implementation. In these regards, we review some of the pertinent theoretical properties of the employed MLCG and describe techniques used to obtain such sequences serially. Our investigation indicates that the MLCG, with properly selected parameters, can be a good, portable, user-specified, and user-controlled generator with acceptable quality. During the simulation of tissue growth, our various experiments have also shown that the ratio of the total number of random numbers consumed till confluence to the total number of computational sites in the cellular array never exceeds a certain number. This number can be used as a predictor for the period of a PRNG needed to run a particular experiment to simulate tissue growth and to estimate when a longer period may be required in order to deal with very large data sets.

We consider a model of a magnetic sample with distribution of Barkhausen switch sites which reverse their moments at a constant rate. Switching is considered in the case that reversal is induced by the incidence of a domain wall. The induced current distribution J of symmetrically placed regions has already been determined. The loss calculation involves summing J2 over switching regions in the plane of the moving wall, and summing as the wall traverses a full cycle. Averaging techniques are employed and the expected loss over unit volume, per cycle is found, due solely to the Barkhausen regions. This is the classic static or ’’hysteresis’’ loss. In a later report the analysis is extended to determine the full losses.

The unsteady full potential equation in three dimensions is solved in conservation form by an implicit triple approximate factorization scheme. The method employs internal Newton iterations, at each time level, to achieve time accuracy and computational efficiency. A robust flux biasing procedure is implemented to provide the necessary artificial viscosity for treating hyperbolic regions bounded by shocks and sonic surfaces. The resulting three-dimensional unsteady computer program is fully vectorized for the CRAY-X/MP. Steady state solutions (three orders of magnitude drop in residual) are usually obtained in i00 iterations requiring 30 seconds of CPU time on the CRAYS/MP, for 32,000 grid points. A full cycle of unsteady calculations for a wing in harmonic pitch (reduced frequency N 0.1 to 0.2) is usually computed in less than 100 tinie steps requiring at most two internal Newton iterations to maintain time accuracy. Results are presented for several wing cases wi th wing sweeps ranging from 0' to 65'. Comparisons with experimental data for steady and unsteady cases are in good agreement.

Symmetric distributed termination algorithms are systematically developed. Solution are first presented in an abstract setting of Dijkstra, Feijen and Van Gasteren [DFG] and then gradually transformed into solutions to the distributed termination problem of Francez [F]. The initially used global real time clock is eventually replaced by local virtual clocks. A dependence between the degree of clock synchronization and the efficiency of the solutions is indicated.

The theme of this conference is the future direction and prospects for systems research. Predicting the future for any form of complex phenomena is very difficult and it is not the intention of this paper to do so for Soft Systems Methodology (SSM). However, the difficulty of predicting future directions does not mean that any attempt to guide or manage the future can be abandoned. The challenge is to “manage” research rather than envisage it as a totally random process. This paper therefore explores some thinking about managing the future direction of SSM.

This article describes for the first time the full cycle of development from raw material cultivation to real-life application of a truly sustainable and scalable filter paper material intended for ...

Summarization: A ramp metering control algorithm includes typically two distinct components: the (most important) control strategy, which makes real-time decisions on the ramp exit flow to be implemented, and the translation of this decision into specific traffic light settings according to the applied metering policy. This study focuses on the second component, providing an overview of practiced metering policies (one car per green, n cars per green, full cycle, and discrete release rates) along with a discussion of their advantages and shortcomings. Further related issues, such as traffic signals, multiple metering lanes, bypass lanes, check-in and check-out detectors, integration of both control components, and on-off switching logic, are also addressed. Παρουσιάστηκε στο: 87th Transportation Research Board Annual Meeting

In the post-World War II period the use of self-service has spread horizontally to practically all types of retail stores on the minimum-service level. Whether labeled “self-selection,” “display merchandising,” “selective open selling,” “simplified selling,” or something similar, all of these represent variously lesser degrees of the supermarket concept of self-service. Whatever it is called, it refers to a still rapidly developing technology co-ordinating the merchandise-presentation efforts of retail stores. This article summarizes the pressures that have been exerted upon retail stores to adopt self-service in greater measure and then identifies the main reasons why some stores prefer to extend more personalized service.

This paper discusses the design trade-offs for a parallel bit-organized MOS memory. A memory capacity of 40K bits can be achieved using LSI techniques. Memory storage capacity is expandable in both word length and number of words stored. The physical dimensions of the memory should be considerably smaller than those of a comparable core design. Power consumption per bit should likewise be less than that achievable with cores. A full cycle time of 1 us or less can be achieved. Cost per bit should compare very favorably with that of a core design.