Molecular dynamics studies on spreading of nanofluids promoted by nanoparticle adsorption on solid surface

Abstract Spreading of nanofluids on solid substrate was studied via molecular dynamics simulations. Simulation models for two immiscible fluids （oil and water based nanofiuids） confined in a slit between two planar solid walls were set up. The influence of the volume concentration of the nanoparticles on the three-phase contact line motion was investigated. We found that the larger volume concentration results in more visible nanoparticle adsorption on solid surface. This effect further induces an advancing displacement of the contact line compared with the meniscus profiles in low concentration case and that with the absence of nanoparticles. These findings are consistent with the previous experimental and theoretical results and provide the atomic-scale understanding on nanofluid spreading.

Numerical Simulation of Level Magnetic Field

According to Maxwell electromagnetic field theory and magnetic vector potential integral equation,a mathematical model of LMF(Level Magnetic Field)for EMBR(Electromagnetic brake)was proposed,and the reliable software for LMF calculation was developed.The distribution of magnetic flux density given by numerical simulation shows that the magnetic flux density is greater in the magnet and magnetic leakage is observed in the gap.The magnetic flux density is uniform in horizontal plane and a peak is observed in vertical plane.Furthermore,the effects of electromagnetic and structural parameters on magnetic flux density were discussed.The relationship between magnetic flux,electromagnetic parameters and structural parameters is obtained by dimensional analysis,simulation experiment and least square method.

Universal critical properties of the Eulerian bond-cubic model

We investigate the Eulerian bond-cubic model on the square lattice by means of Monte Carlo simulations, using an efficient cluster algorithm and a finite-size scaling analysis. The critical points and four critical exponents of the model are determined for several values of n. Two of the exponents are fractal dimensions, which are obtained numerically for the first time. Our results are consistent with the Coulomb gas predictions for the critical O（n） branch for n 〈 2 and the results obtained by previous transfer matrix calculations. For n = 2, we find that the thermal exponent, the magnetic exponent and the fractal dimension of the largest critical Eulerian bond component are different from those of the critical 0（2） loop model. These results confirm that the cubic anisotropy is marginal at n = 2 but irrelevant for n〈2.

Audit of Auditoriums in an Academic Setting, Ghana

Auditorium buildings are special structures needing much attention for it to function properly. Generally, consideration should be given to seating, sightlines, and acoustic requirements. In addition, the design should ensure performer-audience intimacy as much as possible. The focus of the study is to review design strategies for auditoria on the Kwame Nkrumah University of Science and Technology, Kumasi campus towards compliance and to develop solutions for improvements that will enhance the performance of 4 selected auditorium facilities. Case study, observation and measurements were the main strategies used. The results revealed that the approaches involved in auditorium designs are shape, volume, surface boundary dimensions and materials, stage, seating, foyers and sightlines. These parameters are grouped under acoustical, functional and programmatic parameters. Reverberation time calculated was high which indicated speech intelligibility problems, hence, improvement efforts were made to change the floor materials from polished tiles to carpeted floors, and high absorption wall claddings. In the process, the reverberation time was reduced from 1.47 - 2.23 to 0.84 - 1.73 for the studied buildings. The study recommends strict adherence to standards and guidelines, and for designers to have a keen focus on designing these special buildings. A renovation effort when undertaken, will lead to improvements in the performance of the selected buildings.

Study on the Influencing Factors of“Internet+”Recycling of Waste Mobile Phone Dominated by Retailers

The popularization of smartphones and the acceleration of their replacement lead to a surge in mobile phone disposal.How to recycle waste mobile phones efficiently becomes a major problem in today’s society.The“Internet+”recycling mode is an effective way to solve this problem.The recycling process of waste mobile phones involves retailers,manufacturers,third parties and other recycling parts.Retailers have natural advantages compared with other parts because of their perfect sales network and logistics system.The system dynamics model for“Internet+”recycling of waste mobile phones dominated by retailers is constructed,and the Vensim software is used to simulate the influence of changes in two key factors in“Internet+”recycling environment:Annual operating cost of online platform and offline unit logistics cost on retailers’recycling volume and recycling profit.The results show that the investment of online platform operation cost is conducive to the increase of retailers’online waste mobile phone recycling volume and recycling profit,while the investment of offline logistics cost increases retailers’online waste mobile phone recycling volume,but reduces the recycling profit.

Detailed and clock-driven simulation for HPC interconnection network

Performance and energy consumption of high performance computing （HPC） interconnection networks have a great significance in the whole supercomputer, and building up HPC interconnection network simulation plat- form is very important for the research on HPC software and hardware technologies. To effectively evaluate the per- formance and energy consumption of HPC interconnection networks, this article designs and implements a detailed and clock-driven HPC interconnection network simulation plat- form, called HPC-NetSim. HPC-NetSim uses application- driven workloads and inherits the characteristics of the de- tailed and flexible cycle-accurate network simulator. Besides, it offers a large set of configurable network parameters in terms of topology and routing, and supports router＇s on/off states. We compare the simulated execution time with the real execution time of Tianhe-2 subsystem and the mean error is only 2.7%. In addition, we simulate the network behaviors with different network structures and low-power modes. The results are also consistent with the theoretical analyses.