Advanced Materials Research Vols. 488-489

Abstract: The term “cyber-physical system (CPS)” refers to a computing system that integrates physical processes and computational devices via a network. There are many physical and computational devices in a CPS, which can function automatically through inter-device interactions. Because a CPS is usually used for large-scale complex systems, to ensure reliable CPS operation, its design and execution should be verified through simulations. For CPS simulation, a communication protocol should be established for data transmission between physical systems and the corresponding simulation models during the simulation, including control algorithms for regulating differences between the two systems. First, because physical systems and simulation models are advanced in real time and logical time, respectively, time regulation methods should be included in the control algorithm. Second, to simulate various types of physical systems, a flexible simulation environment, independent of the operating environment such as the type of communication middleware, is required. In this paper, we propose a communication protocol for data transmission between physical systems and simulation models via a middle layer that contains the policies for handling the two different clocks of each system: virtual and real. The proposed communication protocol can be used not only for communication between the two systems but also for overcoming the problems caused by the differences in their operating environments. The contribution of this work is in that it defines a communication protocol and proposes methods for controlling different types of systems.

Abstract: Consumer price index (CPI) was a main scientific ground for manager to put forward price policy, wage policy, and national economy development strategy. A lot of study and prediction were carried out for CPI by many scientists, and corresponding achievement was obtained. However, the simple network was applied to the past perdition methods, and the prediction results was not good. The prediction method based on the combinatorial and optimal networks of BP network, Elman network, RBF network and GRNN network was established and applied to the prediction of consumer price index. The simulation results showed that the effect of the combinatorial and optimal method was better than that of single method.

Abstract: Distributed simulation refers to the execution of a complex model on geographically dispersed simulators, and it can increase the speed of a simulation and eventually decrease the simulation execution time. The distributed simulation enables models to be executed in physically distributed position. The system entity structure (SES) is used to represent the structural relation of simulation models and there are several SES’s XML representation methods. To make use of the SES in a distributed simulation environment, the revision of existing XML representation is needed. In this paper, we propose revised XML representation for loading models dynamically in the distributed simulation environment. A template of XML representation is defined to meet a number of modeling requirements, and it shows the specific information of model’s hierarchy and coupling. Each simulator’s model loader analyzes the XML-based SES representations and loads information of a model dynamically. We validate our method using a coupled model example.

Abstract: This research consider a project scheduling problem with the object of minimizing weighted earliness-tardiness penalty costs, subject to precedence relations among the activities and resource-constrained. Project activities are assumed to have a known deterministic due date, a unit earliness as well as a unit tardiness penalty cost and constant renewable resource requirements. The objective is to schedule the activities in order to minimize the total weighted earliness–tardiness penalty cost of the project subject to the finish–start precedence constraints and the constant renewable resource availability constraints. With these features the problem becomes highly attractive in just-in-time environments. A genetic algorithm (GA) is proposed to solve this model. In addition design of experiments and response surface methodology are employed to tune the GA parameters and to evaluate the performance of the proposed method in 270 test problems. The results of the performance analysis will be shown at the end of this paper.

Abstract: In this paper, we proposed a new edge tracing method with high robustness to noise. Through representing edge with maximal gradient path encoded by chain code, the edge tracing problems can be converted into combinatorial optimization problems, and so they can be solved by genetic algorithm. We optimized the traditional genetic algorithm in order to improve the convergence rate. Our method is effective to edges with any shape because it does not require any prior knowledge about the edges. In this paper we also discussed the problem of edge winding and folding and expatiated how to avoid it by designing proper gene coding method and punishment function. Furthermore, by transforming the region of interests from Cartesian coordinates to polar coordinates before edge tracing, this method can be used for closed edges. The experimental results show this is an effective edge tracing method with high robustness and flexibility.

Abstract: In the present study, the influence of addition of various loads of hydrophobic nano silica on modulus of an acrylic melamine automotive topcoat was investigated. The results indicated that addition of hydrophobic nano silica to acrylic melamine decreased its Young’s modulus. The same behavior was observed for nano indentation modulus just at low nano silica content. This property was increased at high nano silica content. Poor interaction between nano particles / acrylic melamine and ball bearing effects of nano particles were used to explain decrease in modulus. Increase in nano indentation modulus was attributed to particle flocculation.

Abstract: In the present work, nano-silica was used in preparing LLDPE/nano-silica as an outer layer film for LLDPE reinforced nano-silica/LDPE/LLDPE multilayer film for microwavable packaging materials in future work. Thus, the objective of this work was studied the optimal of modified nano-silica loading into LLDPE film on barrier and mechanical properties. The experiments were divided into 2 main steps: surface treatment of nano-silica with vinyltriethoxysilane by ultrasonic agitation, and preparation of linear low density polyethylene film reinforced with untreated and treated nano-silica which different silica quantities are 1, 3, and 5 phr by blown film extruder. And then the surface morphology of films was examined by SEM. The properties of the film were analysis, oxygen transmission rate of film was characterized by OTR, water vapor transmission rate of film was characterized by WVTR, and tensile properties (tensile strength, % elongation and modulus) of films were examined by universal testing machine. Results indicated that the LLDPE loaded with 1 phr of nano-silica treated with vinyltriethoxysilane had better tensile strength and % elongation than at 3 and 5 phr of treated and untreated nano-silica.

Abstract: In the present work ionic liquid has been used for the regeneration of cellulose from waste writing paper. The regenerated cellulose was characterized by TGA, FTIR and XRD analyses. Kinetics of thermal degradation of this cellulose was carried out under dynamic condition using thermogravimetry. Coats-Redfern kinetic model was used to determine the kinetic parameters for the degradation process. The activation energy for the thermal degradation of the regenerated cellulose has been found to be less than the precursor waste paper.

Abstract: The study of platinum/carbon black (Pt/CB) versus platinum/single wall carbon nanotubes (Pt/SWCNT) and drying temperature on the result products were investigated. The synthesized of Pt/CB versus Pt/SWCNT were used for coating on fluorine-doped tin oxide (FTO) conductive glasses and tested for electrical conductivity properties used for counter electrode in a dye-sensitized solar cell (DSSC).The result products were characterized in term of chemical composition and microstructure by scanning electron microscope technique (SEM), EDX (JEOL,JSM 5800 LV) and TEM analyses.

Abstract: The removal of monoaromatic (benzene (B) and toluene (T)) from aqueous solution by multi walled, single walled, and hybrid carbon nanotubes (MWCNTs, SWCNTs, and HCNTs) was evaluated for a nanomaterial dose of 1 g/l, concentration of 10-100 mg/l, and pH 7. The equilibrium amount removed by SWCNTs (B: 9.98 mg/g and T: 9.96 mg/g) was higher than for MWCNTs and HCNTs. Toluene has a higher adsorption tendency on CNTs than benzene, which is related to the increasing water solubility and the decreasing molecular weight of the compounds. The SWCNTs performed better for B and T sorption than the MWCNTs and HCNTs. Isotherms study based on isofit program, indicate that the Generalized Langmuir-Freundlich (GLF) isotherm expression provides the best fit for benzene sorption and Brunauer-Emmett-Teller (BET) isotherm is the best fit for toluene adsorption by SWCNT. SWCNTs are efficient B and T adsorbents and possess good potential applications to water and wastewater treatment and maintain water of high quality that could be used for cleaning up environmental pollution.