107 research outputs found

    Dynamic small world network topology for particle swarm optimization

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    Abstract: A new particle optimization algorithm with dynamic topology is proposed based on a small world network. The technique imitates the dissemination of information in a small world network by dynamically updating the neighborhood topology of the particle swarm optimization(PSO). In comparison with other four classic topologies and two PSO algorithms based on small world network, the proposed dynamic neighborhood strategy is more eÆective in coordinating the exploration and exploitation ability of PSO. Simulations demonstrated that the convergence of the swarms is faster than its competitors. Meanwhile, the proposed method maintains population diversity and enhances the global search ability for a series of benchmark problems

    Niching particle swarm optimization based euclidean distance and hierarchical clustering for multimodal optimization

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    Abstract : Multimodal optimization is still one of the most challenging tasks in the evolutionary computation field, when multiple global and local optima need to be effectively and efficiently located. In this paper, a niching Particle Swarm Optimization (PSO) based Euclidean Distance and Hierarchical Clustering (EDHC) for multimodal optimization is proposed. This technique first uses the Euclidean distance based PSO algorithm to perform preliminarily search. In this phase, the particles are rapidly clustered around peaks. Secondly, hierarchical clustering is applied to identify and concentrate the particles distributed around each peak to finely search as a whole. Finally, a small world network topology is adopted in each niche to improve the exploitation ability of the algorithm. At the end of this paper, the proposed EDHC-PSO algorithm is applied to the Traveling Salesman Problems (TSP) after being discretized. The experiments demonstrate that the proposed method outperforms existing niching techniques on benchmark problems, and is effective for TSP

    Function of TRP channels in monocytes/macrophages

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    The transient receptor potential channel (TRP channel) family is a kind of non- specific cation channel widely distributed in various tissues and organs of the human body, including the respiratory system, cardiovascular system, immune system, etc. It has been reported that various TRP channels are expressed in mammalian macrophages. TRP channels may be involved in various signaling pathways in the development of various systemic diseases through changes in intracellular concentrations of cations such as calcium and magnesium. These TRP channels may also intermingle with macrophage activation signals to jointly regulate the occurrence and development of diseases. Here, we summarize recent findings on the expression and function of TRP channels in macrophages and discuss their role as modulators of macrophage activation and function. As research on TRP channels in health and disease progresses, it is anticipated that positive or negative modulators of TRP channels for treating specific diseases may be promising therapeutic options for the prevention and/or treatment of disease

    The First Integrals of a Second Order Ordinary Differential Equation and Application

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    The first integrals of second order ordinary differential equations are considered. The necessary conditions of the existence of analytical first integrals for the equation are presented. Then, the first integrals of the equation are obtained using Lie symmetry method. The results of the first integrals are applied to certain classes of partial differential equations, the conditions of nonexistence of the traveling wave solutions of the partial differential equations are obtained, and traveling wave solutions of the equations under the certain parametric conditions are also obtained

    Emergency mortality of non-trauma patients was predicted by qSOFA score.

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    ObjectiveThis study was aimed to evaluate the performance of quick sequential organ failure assessment (qSOFA) in predicting the emergency department (ED) mortality of non-trauma patients and to expand the application scope of qSOFA score.MethodsA single, retrospective review of non-trauma patients was conducted in ED between November 1, 2016 and November 1, 2019. The qSOFA score was obtained from vital signs and Glasgow Coma Scale (GCS) score. The outcome was ED mortality. Multivariable logistic regression analysis was performed to explore the association between the qSOFA score and ED mortality. The area under the receiver operating characteristic (AUROC) curve, the best cutoff value, sensitivity and specificity were performed to ascertain the predictive value of the qSOFA score.Results228(1.96%) of the 11621 patients were died. The qSOFA score was statistically higher in the non-survival group (PConclusionThe qSOFA score was associated with ED mortality in non-trauma patients and showed good prognostic performance. It can be used as a general tool to evaluate non-trauma patients in ED. This is just a retrospective cohort study, a prospective or a randomized study will be required

    Low-Cyclic Loading Tests of Self-Centering Variable Friction (SCVF) Brace

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    A novel assembled self-centering variable friction (SCVF) brace is proposed which is composed of an energy dissipation system, a self-centering system, and a set of force transmission devices. The hysteretic characteristics and energy dissipation of the SCVF brace with various parameters from low-cyclic loading tests are presented. A finite element model was constructed and tested under simulated examination for comparative analysis. The results indicate that the brace shows an atypical flag-type hysteresis curve. The SCVF brace showed its stable self-centering ability and dissipation energy capacity within the permitted axial deformation under different spring and friction plates. A larger deflection of the friction plate will make the variable friction of this SCVF brace more obvious. A higher friction coefficient will make the energy dissipation capacity of the SCVF brace stronger, but the actual friction coefficient will be lower than the design value after repeated cycles. The results of the fatigue tests showed that the energy dissipation system formed by the ceramic fiber friction blocks and the friction steel plates in the SCVF brace has a certain stability. The finite element simulation results are essentially consistent with the obtained test results, which is conducive to the use of finite element software for calculation and structural analysis in actual engineering design

    Anodic Polarization Behavior of X80 Steel in Na<sub>2</sub>SO<sub>4</sub> Solution under High Potential and Current Density Conditions

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    X80 steel has great risk of corrosion in high voltage direct current (HVDC) interference cases. In this study, the anodic polarization behavior of X80 steel under high potential and current density in Na2SO4 solution was investigated. The I &#215; R drop was eliminated using current interrupt technique during the potentiodynamic measurement. Therefore, the real polarization curve was obtained. The corrosion behavior was investigated by galvanostatic polarization, scanning electron microscopy, and X-ray photoelectron spectroscopy. The results show a new form of passivation route. The steel dissolved actively below &#8722;0.388 VSCE, then became partly passivated from &#8722;0.388 to 1.448 VSCE, and fully passivated above 1.448 VSCE. The passive film was formed containing Fe2O3 and FeOOH, and resistant to SO42&#8722; ions. It not only blocked the direct dissolution of steel, but also facilitated oxygen evolution. The corrosion rates of steel samples decreased after the passivation

    Spatio-Temporal Differentiation of Urban-Rural Equalized Development at the County Level in Chengdu

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    Urban-rural equalized development (URED) is recognized as strongly contributing to the narrowing of societal, economic, life, and environmental gaps between urban and rural areas and is also an effective way to solve the “three rural issues” of rapid industrialization and urbanization in China. This paper explores the spatio-temporal patterns of URED in the state-designated experimental zone of Chengdu at a county level by using quantitative survey data from 2004 to 2013. The major findings are as follows: (1) the regions that are closer to the central city of Chengdu had a more optimistic urban-rural equalized development outlook (i.e., the three-tier geographical distribution phenomenon); (2) this distribution characteristic was gradually broken up in the process of urban and rural integration, and the differences between the three tiers has been narrowing; and (3) the gap between urban and rural areas has been significantly improved and exhibited a higher dynamic degree in the second and third tiers than in the first tier, which suggests a new development mode that exhibits better quality and higher sustainability. Given these results, the development orientation and strategy of each tier are discussed according to the characteristics of urban and rural equalized development

    Synthesize of silicon/carbon nanosheets with NaCl template and its application as anode material of lithium-ion batteries

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    Lithium-ion batteries (LIBs) are used extensively in various applications such as mobile phones and portable computer. Silicon (Si) is regarded as a kind of promising anode material in LIBs because of its high theoretical capacity and low working potential. The major challenges related to Si anodes are their huge volume changes and poor conductivity during lithiation-delithiation. Herein, a two-dimensional structure of Si/petroleum pitches based carbon nanosheets (Si/CNSs) was successfully synthesized via a green and recyclable NaCl template method. This peculiar structural feature of Si/CNS can effectively accommodate the volume expansion of Si anodes and improve their electrochemical performance. A typical sample of Si/CNS-2 exhibits a high reversible capacities of 901mAhg(-1) at 100mAg(-1), good cycling stability (capacity retention of 655mAhg(-1) after 100 cycles at 300mAg(-1)) and excellent rate capability (533mAhg(-1) at 2Ag(-1)). This approach is simple and environment-friendly, which may supply a practicality way to prepare Si-based anode materials for high-performance LIBs
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