摘要 :
A fundamental problem with run-time monitoring of parallel programs is the intrusion introduced by instrumenting the original program. In order to minimize the amount of in- trusion in monitoring parallel programs, the logical clo...
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A fundamental problem with run-time monitoring of parallel programs is the intrusion introduced by instrumenting the original program. In order to minimize the amount of in- trusion in monitoring parallel programs, the logical clock approach (LCA) was proposed. It uses logical clocks to time and control the ordering of communication events during moni- toring, and to reflect the real execution behavior when running without monitoring. However, the main problem with LCA is that in the case of non-deterministic communication and when several processes wait on each other's logical clock to advance, an interlock situation may occur, where none of the processes can continue to execute. This paper presents a strategy to avoid the interlock situations, based on the concept of ready condition. How the logical clocks are updated and communications are controlled in order to maintain the ordering of events, using a relaxed communication model, will be described. Compared with the original LCA, the new interlock avoidance approach is simpler and introduces less overhead. In addition, the modified logical clock mechanisms introduced in this paper are more general and applicable to a wider range of parallel computing systems.
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Pulsed laser deposition (PLD) was used to deposit FePt films onto single crystalline MgO substrates. When deposited at room temperature, films grow epitaxial within the Al phase. Structure and magnetic properties were examined by ...
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Pulsed laser deposition (PLD) was used to deposit FePt films onto single crystalline MgO substrates. When deposited at room temperature, films grow epitaxial within the Al phase. Structure and magnetic properties were examined by X-ray diffraction, Rutherford Backscattering Spectrometry (RBS), magneto-optic Kerr effect, Moessbauer spectroscopy, and Magnetic Orientation Mossbauer Spectroscopy (MOMS). These measurements allow to exclude local ordering and reveal the anisotropic intrinsic and extrinsic magnetic properties. These results are discussed with respect to the texture and microstructure of these films.
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We report on the ultraviolet (UV)-radiation sensing of pulsed-laser deposited In_2O_3: SnO_2: ZnO films grown on glass substrates. The films demonstrate sharp increase (～0.35 Ω) in electrical resistance on UV illumination. The r...
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We report on the ultraviolet (UV)-radiation sensing of pulsed-laser deposited In_2O_3: SnO_2: ZnO films grown on glass substrates. The films demonstrate sharp increase (～0.35 Ω) in electrical resistance on UV illumination. The resistance of the films shows strong spectral (in the vicinity of 325 nm) and power dependence. This is explained due to the presence of defects located at lattice disorders that generate levels within the semiconductor band gap and originate depletion region around them when charged. This reduces the effective conduction region, increasing the effective resistance. These results show new possibilities for the low-cost high performance UV radiation sensors for biosafety.
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We report on the feasible fabrication of microfluidic devices for noncontact particle trapping. A half-wavelength resonator was constructed using standard soft lithography to generate ultrasonic standing waves through a miniature ...
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We report on the feasible fabrication of microfluidic devices for noncontact particle trapping. A half-wavelength resonator was constructed using standard soft lithography to generate ultrasonic standing waves through a miniature piezoelectric transducer.
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摘要 :
A two-layer spherical α~2 dynamo model consisting of an inner electrically conducting core (magnetic diffusivity λ_i and radius r_i) with α = 0 surrounded by an electrically conducting spherical shell (magnetic diffusivity λ_o...
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A two-layer spherical α~2 dynamo model consisting of an inner electrically conducting core (magnetic diffusivity λ_i and radius r_i) with α = 0 surrounded by an electrically conducting spherical shell (magnetic diffusivity λ_o and radius r_o) with a constant α is shown to exhibit oscillatory behavior for values of β = λ_i/λ_o and r_i/r_o relevant to the solar dynamo. Time-dependent dynamo solutions require r_i/r-o ≥ 0.55 and β ≤ O(1). For the Sun, r_i/r_o is about 0.8 and β ≈ 10~-3. The timescale of the oscillations matches the 22 yr period of the sunspot cycle for λ_o = O(10~2 km~2 s~-1). It is unnecessary to hypothesize an α-ω dynamo to obtain oscillatory dynamo solutions; an α~2 dynamo suffices provided the spherical shell region of dynamo action lies above a large, less magnetically diffusive core, as is the case for the solar dynamo.
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We present measurements of D → K_S~0π and D → K_L~0π branching fractions using 281 pb~(-1) of ψ(3770) data at the CLEO-c experiment. We find that B(D~0 → K_S~0π~0) is larger than B(D~0 → K_L~0π~0), with an asymmetry of R...
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We present measurements of D → K_S~0π and D → K_L~0π branching fractions using 281 pb~(-1) of ψ(3770) data at the CLEO-c experiment. We find that B(D~0 → K_S~0π~0) is larger than B(D~0 → K_L~0π~0), with an asymmetry of R(D~0) = 0.108 ± 0.025 ± 0.024. For B(D~+ → K_S~0π~+) and B(D~+ → K_L~0π~+), we observe no measurable difference; the asymmetry is R(D+) = 0.022 ± 0.016 ± 0.018. The D° asymmetry is consistent with the value based on the U-spin prediction A(D~0 → K~0π~0)/A(D~0 → K~0π~0) = -tan~2θ_C, where θ_C is the Cabibbo angle.
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