10,233 research outputs found
Experimental and analytical study of the internal recycle-effect on the heat transfer for the power-law fluid in a double-pass flat-plate heat exchanger with constant wall temperature
[[abstract]]A conjugated Graetz problem of the double-pass flat-plate heat exchanger with internal recycle at uniform wall temperature was solved analytically using the orthogonal expansion technique for the power-law fluid. The mathematical formulation was derived for a fully developed laminar flow through the flat-plate channels by ignoring axial conduction and assuming temperature-independent fluid properties. A constant wall temperature, and both the continuous temperature and the same heat flux at the interface of the two adjacent subchannels made by inserting an impermeable sheet in between, were considered as the thermal boundary conditions. Experiments were carried out in order to validate the proposed mathematical formulation and the results can be very satisfactory. It is found that the recycle ratio and the impermeable-sheet position play significant influences on the efficiencies of this double-pass flat-plate heat exchanger. But, if the power consumption is also evaluated, the performance declines for the double-pass heat exchanger with large reflux ratios. The heat-transfer efficiency enhancement for the power-law fluid with a smaller power-law index is found to be less than that with a larger one, however, if both the heat transfer efficiency and the power consumption increment are considered together, the fluid with a smaller index would have a higher performance.[[notice]]補正完畢[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子
Fault-Tolerant Circuit-Switching Networks
The authors consider fault-tolerant circuit-switching networks under a random switch failure model. Three circuit-switching networks of theoretical importance—nonblocking networks, rearrangeable networks, and superconcentrators—are studied. The authors prove lower bounds for the size (the number of switches) and depth (the largest number of switches on a communication path) of such fault-tolerant networks and explicitly construct such networks with optimal size Θ( n (log n)2 ) and depth Θ( log n )
Study of and decays
We study the charmless two-body
and three-body decays. We obtain to agree with the
recent LHCb measurement. However, we find that is unable to explain the
LHCb observation of , which implies the possibility for other
contributions, such as that from the resonant decay with as a higher-wave baryon state. For
, we show that ,
which are consistent with the current data of , respectively. Our results also support the relation of ,
given by the previous study.Comment: 8 pages, 1 figure, revised version accepted by EPJ
An Integrated Method Based on PSO and EDA for the Max-Cut Problem
The max-cut problem is NP-hard combinatorial optimization problem with many real world applications. In this paper, we propose an integrated method based on particle swarm optimization and estimation of distribution algorithm (PSO-EDA) for solving the max-cut problem. The integrated algorithm overcomes the shortcomings of particle swarm optimization and estimation of distribution algorithm. To enhance the performance of the PSO-EDA, a fast local search procedure is applied. In addition, a path relinking procedure is developed to intensify the search. To evaluate the performance of PSO-EDA, extensive experiments were carried out on two sets of benchmark instances with 800 to 20000 vertices from the literature. Computational results and comparisons show that PSO-EDA significantly outperforms the existing PSO-based and EDA-based algorithms for the max-cut problem. Compared with other best performing algorithms, PSO-EDA is able to find very competitive results in terms of solution quality
Non-leptonic two-body weak decays of
We study the non-leptonic two-body weak decays of with () representing as the baryon (meson) states. Based
on the flavor symmetry, we can describe most of the data reexamined by
the BESIII Collaboration with higher precisions. However, our result of is larger than the
current experimental limit of (90\% C.L.) by BESIII. In
addition, we find that , , and , which are accessible
to the BESIII experiments.Comment: 12 pages, 1 figure, revised version accepted by PL
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