5,688 research outputs found
Structure controllability of complex network based on preferential matching
Minimum driver node sets (MDSs) play an important role in studying the
structural controllability of complex networks. Recent research has shown that
MDSs tend to avoid high-degree nodes. However, this observation is based on the
analysis of a small number of MDSs, because enumerating all of the MDSs of a
network is a #P problem. Therefore, past research has not been sufficient to
arrive at a convincing conclusion. In this paper, first, we propose a
preferential matching algorithm to find MDSs that have a specific degree
property. Then, we show that the MDSs obtained by preferential matching can be
composed of high- and medium-degree nodes. Moreover, the experimental results
also show that the average degree of the MDSs of some networks tends to be
greater than that of the overall network, even when the MDSs are obtained using
previous research method. Further analysis shows that whether the driver nodes
tend to be high-degree nodes or not is closely related to the edge direction of
the network
A comprehensive analysis of Fermi Gamma-Ray Burst Data: IV. Spectral lag and Its Relation to Ep Evolution
The spectral evolution and spectral lag behavior of 92 bright pulses from 84
gamma-ray bursts (GRBs) observed by the Fermi GBM telescope are studied. These
pulses can be classified into hard-to-soft pulses (H2S, 64/92),
H2S-dominated-tracking pulses (21/92), and other tracking pulses (7/92). We
focus on the relationship between spectral evolution and spectral lags of H2S
and H2S-dominated-tracking pulses. %in hard-to-soft pulses (H2S, 64/92) and
H2S-dominating-tracking (21/92) pulses. The main trend of spectral evolution
(lag behavior) is estimated with
(), where is the peak photon
energy in the radiation spectrum, is the observer time relative to the
beginning of pulse , and is the spectral lag of photons
with energy with respect to the energy band - keV. For H2S and
H2S-dominated-tracking pulses, a weak correlation between
and is found, where is the pulse width. We also study the spectral
lag behavior with peak time of pulses for 30 well-shaped pulses
and estimate the main trend of the spectral lag behavior with . It is found that is correlated with
. We perform simulations under a phenomenological model of spectral
evolution, and find that these correlations are reproduced. We then conclude
that spectral lags are closely related to spectral evolution within the pulse.
The most natural explanation of these observations is that the emission is from
the electrons in the same fluid unit at an emission site moving away from the
central engine, as expected in the models invoking magnetic dissipation in a
moderately-high- outflow.Comment: 58 pages, 11 figures, 3 tables. ApJ in pres
Temperature-controlled electrospinning of EVOH nanofibre mats encapsulated with Ag, CuO, and ZnO particles for skin wound dressing
To treat skin burns, a new wound dressing, nanofibre mats with metal or metal oxide nanoparticles (Ag, CuO, and ZnO), was fabricated using the electrospinning technique. During a therapeutic process, the antibacterial ability and bio-compatibility of a new dressing material are of major concern. To expound the characteristics of ethylene vinyl alcohol (EVOH) nanofibre mats encapsulated with metal or metal oxide nanoparticles, denoted as Ag-EVOH, CuO-EVOH, and ZnO-EVOH, for use as new wound dressing materials, we investigated the suitable processing parameters to fabricate these materials, such as the voltage, tip-to-collector distance, concentration of the solution, and effect of environmental temperature. The antibacterial ability and bio-compatibility of Ag-EVOH, CuO-EVOH, and ZnO-EVOH were then tested and quantified. The outcomes show that the most suitable temperature for the fabrication of the materials is 40 °C (±3 °C). The antibacterial experiment results indicate that 0.08 g/ml of metal/metallic oxide shows the highest antibacterial ability toward Staphylococcus aureus. Furthermore, the largest diameters of the bacteriostatic loops of the three types of nanofibre mats, i.e. Ag-EVOH, CuO-EVOH, and ZnO-EVOH, are 5.89, 5.21, and 4.12 mm, respectively. Finally, the cell proliferations on the three nanofibre mats show a similar growth trend
Anesthetic management for cesarean section in a patient with uncorrected double-outlet right ventricle
Robotic spleen-preserving laparoscopic distal pancreatectomy: a single-centered Chinese experience
Modeling of Signal Plans for Transit Signal Priority at Isolated Intersections under Stochastic Condition
Transit signal priority (TSP) is recognized as having the potential to improve transit service reliability at small cost to general traffic. The popular preference for TSP encounters the challenges of various and challenging test scenarios. According to the stochastic characteristics of traffic flow, the signal timing model was established for TSP at an isolated signal intersection, where the passenger average delay was used as the optimization objective, and the weights of all phases were considered. The priority logic that is considered in the study provides cycle length and green time within a fixed-time traffic signal control environment. Using the Gauss elimination, the quantitative relationships were determined between phase clearance reliability (PCR), cycle length, and green time. Simulation experiments conducted by the particle swarm optimization (PSO) algorithm indicated that (1) the random variation of arrival rate has an obvious effect on traffic signal settings; (2) the proposed TSP model can reduce passenger delays, especially under stochastic traffic flow.</jats:p
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