Applied Mechanics and Materials Vol. 302

Abstract: Reverse engineering technology is an important part of advanced manufacturing technology. The CAM module is one of the key modules of integrated reverse engineering CAD/CAM system, its research and development has the important theory significance and project application value for the successful implementation of integrated reverse engineering CAD/CAM system. This paper systematically analyzes the functional model and information integration model of CAM module, using the Pro/Toolkit tool in the Pro/NC environment to achieve CAM function of the technical scheme, and as the basis for the development of the integration in reverse engineering CAD/CAM system, has strong ability of automatic processing module of CAM. Research and development of practice show that the scheme proposed in this paper is more advanced, feasible and practical.

Abstract: A prediction model was built to predict the slagging characteristics of coal ash based on the theory of symmetric fuzzy cross entropy and vague sets. Softening temperature, SiO2-Al2O3 ratio, Alkali-acid ratio, silicon percentage of value were selected as input vectors. Firstly, the vague values of the selected samples were calculated based on vague sets theory, and then the similarity degree was evaluated based on symmetric fuzzy cross entropy. The prediction results prove that the predicting accuracy rate of the new pattern recognition model is 90%. So, the model built here is reasonable and feasible and meets the requirement of engineering.

Abstract: The three dimensional finite element model of a groundwater hydraulic tunnel was eatablished in this paper by FEM software ANSYS, two seismic waves of bedrock wave and EI-centro wave in similar sites were entered, and dynamic time history method was applied to compare the seismic response of the two hydraulic tunnels which were under rigid boundary conditions and viscoelastic boundary conditions respectively. The results showed that, the dynamic response of the model under rigid boundary conditions was larger than the response under viscoelastic boundary, and the viscoelastic boundary was closer to the actual situation. Under viscoelastic boundary conditions, the smaller depth of the hydraulic tunnel, the more intensive of the seismic response.

Abstract: The focus is on the unsteady effect on the flow characteristics considering the real respiration in a human airway. In order to capture the unsteady effect, the flow characteristics were investigated and compared with that of steady flow by using the computational fluid dynamics technique. The real respiratory flow rate in a light workload was appliedto the inlet of airway. The unsteady effects especially appear when the flow rate accelerates in the inspiratory and the expiratory phase than other times in a breath cycle. The size of the flow recirculation zone, the turbulence fluctuation and the secondary flow intensity decrease because the unsteady effect reduces the strength of jets passing through the constriction of airway by interfering with the flow. These results imply that the unsteady effect should be considered to investigate the flow characteristics and the particle movement in a human airway.

Abstract: Virtual reality is an innovative technology, which allows users to immerse in an imagined situation. Therefore, promoting virtual reality technology can provide more natural and specific interaction mode. The purpose of this study is to investigate interactive virtual reality navigation system by testing 15 participants to evaluate the system and analyze the results with Delphi method and Heuristic Evaluation. Besides, we used Questionnaire for User Interaction Satisfaction (QUIS), Usability Metric for User Experience (UMUX) questionnaires and interviews to understand user experience. The results show the new system is better than the old one. The interactive VR navigation system design principles (easy to use, consistency, richness, feedback, simple prompt and documentation) obtained from this study can be used to enhance the satisfaction of the users when designing the interactive VR navigation system in the future.

Abstract: In this study, a numerical simulation is made to understand the effect of the angle of attack on a NACA airfoil, which will be used for a basic shape to apply for making the vertical axis Darius wind turbine. The near-wall y+ value which is less than 1 is known to be most desirable for a near-wall modeling. Therefore, this study is aiming to observe the variation and find the optimized value of y+. The Reynolds number used in this study was 360,000, where the chord length and the velocity were 0.12m and 43.8m/s, respectively. Generally, the lift coefficient of the airfoil tends to increase as the angle of attack increases and it decreases substantially at the stall angle and then it decreases. As expected, the lift coefficient increases rapidly from 0 to 10° and then after the sudden drop of the lift (i.e., the stall) at around 10 to 16° depending on the y+ value. In this paper, it seems to be reliable and appropriate to use y+ value close to 1. From the surface pressure distribution, from the result obtained the ratio of pressure distribution of maximum value to the minimum value was 1.89and these peaks move forward to backward as the angle of attack increases.

Abstract: Supply chain simulation is able to capture the dynamics and uncertainties in all kinds of supply chains and provide quantitative performance evaluations. In order to address the time consuming evaluation and large search space issues in supply chain simulation, this paper proposes a policy-combination oriented optimization approach to conduct decision makings. The approach begins with reducing the search space by relaxing the goal of optimization, and then refers to meta-heuristic searching methods to solve the main bi-level optimization problem. Lastly the key parameters are fine-tuned with what-if analysis. A case study demonstrates the effectiveness and efficiency of the proposed approach, and compares it with other alternative approaches available in practice.

Abstract: Migration and diffusion of oil spill in sea is an extremely complex issue by the impact of the oil features and a variety of environmental factors, undergoing expansion, drift, evaporation, dispersion, emulsification, dissolution, photo-oxidation, biodegradation and their interactionsand many other processes ，at the same time has a direct relationship with the local meteorological conditions and law motionofseawater. Marine oil spill behavior analysis and research of the system, using VB technology and C#technical design and development of a marine oil spill simulation system based on Geographic Information System (GIS). The system using cloud-based GIS for a platform, using the Monte-Carlo method to simulate the behavior of chemicals in seawater on the system of cloud computing, the organic integration of GIS system application model

Abstract: Along with the development of smartphones and tablets world-widely, and the progress of mobile internet and Wi-Fi hotspots, users can acquire information via mobile devices anytime and anywhere.In recent years, Taiwan's tourism is flourishing, more and more foreign travelers come to visit Taiwan.Therefore, providing a user-friendly M-tourism system for foreign travelers can help them to experience more during traveling.We referred the theories of human-computer interface design to develop our M-tourism system—the LBS M-tourism Application.This system not only provides online traveling information, but integrates with location-based services (LBS). The LBS M-tourism Application can use global positioning system (GPS) technology, and provide traveling information or services to the user based on his/ her present location.

Abstract: The purpose of this study is to develop the adaptive terminal sliding mode scheme to control a MEMS resonator with a six-powered potential function for tracking a given reference signal in the presence of system uncertainties and external disturbances. The proposed adaptive controller includes the time-varying feedback gains can tackle the nonlinear dynamics without directly eliminating. Meanwhile, these time-varying feedback gains are adaptively updated according to the suitable updated rules without the known bounds of system uncertainties and external disturbances. Some sufficient conditions to guarantee the stability based on Lyapunov theory and numerical simulations are performed to demonstrate the effectiveness of the presented scheme.