Applied Mechanics and Materials Vols. 110-116

Abstract: The Discrete Dipole Approximation (DDA) method and the Finite Difference Time Domain (FDTD) method are used to analyze silver nanospheres with different radius and the coupling of nanospheres array complementarily. DDA method is used for simulating the extinction spectra of single silver nanosphere and nanospheres array; and the coupling of two nanospheres and their surrounding electric field distribution are simulated by FDTD method. Through these results, we got some important conclusions of nanoparticles’ Localized Surface Plasmon Resonance (LSPR) phenomenon.

Abstract: The urban rain-flood disaster occurs more ordinary and more serious recently. Summing up the characters of urban rain-floods, the mechanism of urban rain-flood disasters is analyzed. More ever, the main countermeasures to prevent urban rain-flood disasters are stated. Finally, the method to use urban rain-flood comprehensively based on nanotechnology is put forward.

Abstract: In this paper, the convective heat transfer of nanofluid flow in a turbulent boundary layer of a flat plate is simulated numerically. Turbulent flow equations with RNG K-ε turbulence model are solved employing Fluent software. Furthermore, the effects of nanoparticle concentration on the heat transfer characteristics are studied. The results show that nanofluids enhance the heat transfer coefficient dramatically with little change in pressure drop.

Abstract: In this paper, two phase heat transfer of a mixture of nanopaticles in air flow as a type of nanofluid is studied. Volume fraction of the dispersed phase is very low (less than 1%). Nanoparticles travel in the base fluid due to drag, brownian and gravity forces and are tracked according to lagrangian approach. Effect of reduced specific heat of nanofluid on heat transfer is considered. The results show an increase in heat transfer rate which is very much more than that predicted by the Maxwell model.

Abstract: It is very essential to know mechanical properties in different regions of nanobio membrane as one of the most important parts of living systems. Here the coarse-grained (CG) simulations method have been used to study the pressure profile in a system including nanobio membrane and water. CG simulations have become an important tool to study many biomolecular processes, exploring scales inaccessible to traditional models of atomistic resolution. One of the major simplifications of CG models is the representation of the solvent, which is either implicit or modeled explicitly as a van der Waals particle. The effect of polarization has been ignored in the initial CG water molecules model. Given the important role of water as a solvent in biological systems, its treatment is very important to the properties derived from simulation studies. Till now two models have been parameterized to simulate water: i) standard MARTINI water and ii) polarizable coarse-grained water model. Both of mentioned water models are proper to be used in combination with the CG MARTINI force field. In this work both of these models have been used for simulation. One micro second CG molecular dynamics simulation has been done for two separate systems. Each system includes water and hydrated 1-palmitoyl-2-oleoyl-1-sn-3-phosphatidylcholine (POPC) lipid nanobio membrane. The difference between two systems is in simulated water models that one system has standard MARTINI water and the other one has polarizable water. In each case pressure profile calculation has been done via Virial pressure theorem. Results indicate that using polarizable water model leads to higher picks in pressure profile in water region near surface of nanobio membrane. This can be related to density of polarizable water and also may play role as a small barrier.

Abstract: Experimental observations have shown that cardio toxins (cobra cytotoxins), small proteins of three-fingered cytotoxin group, damage nanobiomembranes in different cells and vesicles. However, the molecular mechanism of this damage is not yet completely cleared. Molecular dynamics simulations have been used here to study the interaction of cardiotoxins A3 and A4 from Naja atra cobra venom with hydrated 1-palmitoyl-2-oleoyl-1-sn-3-phosphatidylcholine (POPC) lipid bilayer in two separate systems. Each of studied systems included one cytotoxin molecule, 128 lipid molecules (64 molecules in each monolayer) and 11817 water molecules. It has been found that the toxin interacts with zwitterionic bilayer formed by POPC. At the beginning of simulation the cytotoxins have been oriented toward nanobiomembrane surface by their loops’ tips. This orientation has changed during first 50 ns of classical molecular dynamics simulation for both of studied cytotoxins. The A3 toxin finally meets POPC nanobiomembrane with sides of loops near tips including cytotoxin region THR148 and VAL155. The A4 cytotoxin molecule has been finally oriented toward surface of nanobiomembrane with base and one of loop's tip including THR184, ARG186 and LEU158 amino acids, after 50 ns molecular dynamics simulation. Then 25 ns steered molecular dynamics simulation has been done for both of systems. The obtained data suggest that cytotoxin A3 meets the nanobiomembrane with sides of loops near tips and A4 meets POPC nanobiomembrane with base and one of loop's tips. The difference between final orientations of these two cytotoxins comes from the difference in the structure of them.

Abstract: To speed up the construction of Liaoning to make it advanced equipment manufacturing base with international l competitiveness is the inevitable demand of reviving the old industrial base. It is also urgent needs and important practice to carry out the scientific outlook on development and adhere to the new industrial road with Chinese characteristics.

Abstract: Scheduling for job shop is very important in both fields of production management and combinatorial optimization. Since the problem is well known as NP-Hard class, many metaheuristic approaches are developed to solve the medium and large scale problems. One of the main elements of these metaheuristics is the solution seed structure. Solution seed represent the coding structure of real solution. In this paper, a new solution seed for job shop scheduling is presented. This solution seed is compared with a famous solution seed presented for the job shop scheduling. Since the problem is well known as NP-Hard class, a Tabu search algorithm is developed to solve large scale problems. The proposed solution seed are examined using an example and tabu search algorithm.

Abstract: This paper extends the study of Mathirajan et al. (Minimizing total weighted tardiness on a batch-processing machine with non-agreeable release times and due dates. Int. J. Adv. Manuf. Technol., 2010, doi: 10.1007/s00170-009-2342-y) to parallel batch-processing machine problems because these have not been examined to date. For the problem concerning compatible product families, job release times, non-identical job sizes, and varying machine capacities, we propose a mixed integer programming (MIP) model, and a number of simple dispatch-based heuristic and simulated annealing (SA) algorithms. Computational results revealed that the proposed SA is capable of obtaining similar solutions acquired by MIP within a short time. The SA algorithms outperform other heuristic algorithms with respect to solution quality.

Abstract: Hybrid flow shop scheduling problems with multiprocessor tasks to minimize the makespan have been addressed and solved efficiently. Several approaches were used, including greedy methods and metaheuristics. In this paper, we proposed a mixed integer programming (MIP) model that can define explicitly and precisely the nature of a given problem. We also addressed a modified lower bound to obtain tighter bounds. Additionally, we propose different decoding methods and emphasize their importance in hybrid flow shop scheduling problems with multiprocessor tasks. By using existing test problems with n=5 in examining the proposed methods, many optimal solutions can be obtained as benchmarks for reference by the MIP model. Accordingly, the results are indicative of the influence of the decoding methods on the solutions to the hybrid flow shop problems with multiprocessor tasks.