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71.
We analyze the jamming transition that occurs as a function of increasing packing density in a disordered two-dimensional assembly of disks at zero temperature for "Point J" of the recently proposed jamming phase diagram. We measure the total number of moving disks and the transverse length of the moving region, and find a power law divergence as the packing density increases toward a critical jamming density. This provides evidence that the T=0 jamming transition as a function of packing density is a second order phase transition. Additionally, we find evidence for multiscaling, indicating the importance of long tails in the velocity fluctuations. 相似文献
72.
73.
Jennifer A. Clark N. A. J. Hastings 《The Journal of the Operational Research Society》1977,28(1):51-68
Decision Networks is a technique for solving problems which involve a sequence of decisions. It is similar in style to critical path analysis in that it consists of arrow diagrams which give a visual representation of the problem and are used as a basis for a simple calculation procedure. The technique can deal with deterministic and stochastic problems and in the latter case is more general than decision trees. The decision network approach meets the need for a method of solution for multi-stage decision problems which is easily understood, helps the user to visualize the nature of the problem and is routine in application. 相似文献
74.
75.
Abstract— The total radiant flux from a solution containing a radioactive compound, hexadecme-l-14 C, plus an appropriate scintillator, has been determined. The procedure used involves comparison of its luminescent emission with the light scattered by glycogen illuminated with a monochromatic homogeneous light beam of known photon flux. These standards are particularly convenient for use with chemiluminescent and bioluminescent reactions, since the geometry of the emission may be duplicated exactly. 相似文献
76.
77.
R. Hastings 《Physics letters. A》1978,67(4):316-318
Recent data on the yield stress of a low density virus solid are interpreted within the framework of a model for a Coulomb solid. 相似文献
78.
The problem of minimising the overall duration of a project subject to constraints on the availability of resources is considered with particular reference to the use of branch and bound methods. A new resource based bound, new dominance rules and an innovatory network breakdown technique which preserves optimality are reported. Computational experience and comparisons with schedules obtained by decision rule methods are given. 相似文献
79.
A noninvasive, continuous-wave ultrasonic technique was developed to measure the displacement amplitude and phase of mechanical structures. The measurement system was based on a method developed by Rogers and Hastings ["Noninvasive vibration measurement system and method for measuring amplitude of vibration of tissue in an object being investigated," U.S. Patent No. 4,819,643 (1989)] and expanded to include phase measurement. A low-frequency sound source was used to generate harmonic vibrations in a target of interest. The target was simultaneously insonified by a low-power, continuous-wave ultrasonic source. Reflected ultrasound was phase modulated by the target motion and detected with a separate ultrasonic transducer. The target displacement amplitude was obtained directly from the received ultrasound frequency spectrum by comparing the carrier and sideband amplitudes. Phase information was obtained by demodulating the received signal using a double-balanced mixer and low-pass filter. A theoretical model for the ultrasonic receiver field is also presented. This model coupled existing models for focused piston radiators and for pulse-echo ultrasonic fields. Experimental measurements of the resulting receiver fields compared favorably with theoretical predictions. 相似文献
80.
Dragic J Gershon T Abe K Abe K Abe T Aihara H Asano Y Aulchenko V Aushev T Aziz T Bakich AM Banas E Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dong LY Dowd R Eidelman S Eiges V Enari Y Epifanov D Fratina S Gabyshev N Gokhroo G Golob B Gordon A Haba J Hastings NC Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Kang JH 《Physical review letters》2004,93(13):131802
We present the first evidence of the decay B0-->rho(0)pi(0), using 140 fb(-1) of data collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We detect 15.1+/-4.8 signal events with a significance of 3.5 standard deviations and measure the branching fraction to be B(B0-->rho(0)pi(0))=(5.1+/-1.6(stat)+/-0.9(syst))x10(-6). 相似文献