Applied Mechanics and Materials Vols. 241-244

Abstract: To investigate the effects of adopting a pull system in assembly lines in contrast to a push system, simulation software called “ARENA” is used as a tool in order to present numerical results from both systems. Simulation scenarios are created to evaluate the effects of attributes changing in assembly systems, with influential factors including the change of manufacturing system (push system to pull system) and variation of demand. Moreover, pull system manufacturing consists of the addition attribute, which is the number of buffer storage. This paper will provide an analysis based on a previous case study, hence process time and workflow refer to the journal name “Optimising and simulating the assembly line balancing problem in a motorcycle manufacturing company: a case study” [2]. The implementation of the pull system mechanism is to produce a system improvement in terms of the number of Work-In-Process (WIP), total time of products in the system, and the number of finished product inventory, while retaining the same throughput.

Abstract: Mechanism method and neural network identification method are widely used for system modelling. Due to the complexity of actual investigated objects, models built with individual method are usually not good enough for the problems to be solved. Therefore, a hybrid modelling method based on mechanism and identification is presented in the paper. In the hybrid model, the mechanism model is applied as the fundamental model in order to ensure the overall coincidence performance and the identification model is adopted as the compensated model in order to ensure the accuracy performance. The developing process of the hybrid model of a marine turbo-charged diesel is demonstrated in detail in the paper. Testing result shows that the hybrid modelling method is very suitable for modelling complex investigated objects.

Abstract: Put building information modeling concept into the historic building restoration field. Restoration by "layer" sequence as the object of building base portion, main structure, electrical and plumbing pipes and building surface information, greatly expand the historic building data information. Through the project practice of digital restoration, we establish a good connection with historical building research and architectural design teaching, and the most important harvest is that it provides a feasible implementation measures for the historic building protection problem in the process of the city industrial structure adjustment, and builds a general platform at the same time.

Abstract: A new topology of double resonance hybrid APF (DRHAPF) was researched, which can be adopted in 35KV high voltage system. The principle of DRHAPF was analyzed firstly. The harmonic suppressing function was used to analyze the harmonic suppressing performance of DRHAPF in the frequency field. The harmonic suppressing frequency performance of different parameters was obtained. The reactive power compensating performance of the system was also gotten. The simulating and experiment results prove the validity of DRHAPF.

Abstract: The space-domain volume integral equation (VIE) method is presented for the analysis of three-dimension (3-D) scattering from dielectric frequency selective structures (DFSS) involved homogeneous and inhomogeneous lossy material. The method solves directly for the electric field in order to easily enable periodic boundary conditions in the spatial domain. The computation of the spatial domain periodic Green’s function (PGF) is accelerated by the modified Ewald transformation. Optimized interpolation procedures for the PGFs can be applied, resulting in a considerable reduction of matrix-filling time without any significant effect on the accuracy.

Abstract: To deal with the cargo trucks’ problem that handling of cargos is time-consuming due to the buckets of cargos can’t be lifted, this study aims to design a cargo truck with lift bucket. Based on the idea of driving principle, mechanical structure and simulation of overall modeling, this paper proposes a cargo truck model with the lift bucket. Using front-wheel drive, the newly designed cargo truck model drops the bucket near the ground or lands the bucket, which saves manual handling from the original height of bucket to the ground. Thus, operators can load or unload the lift bucket by moving the cargos at the ground level, without using cargo handling platform and lifting system or manually lifting cargos. Transportation can be achieved simply by lifting the bucket. This model not only saves manual power, but also improves handling efficiency.

Abstract: Vehicle safety is of great importance to improve the capability and performance of the transportation system. To deal with safety threats most probably caused by the vehicle collisions in unsignalized intersections, concept of vehicle infrastructure cooperation provides a perspective and challenging solution to enable sufficient information interaction by V2V and V2I communication, which make it feasible to avoid collisions more autonomously. In vehicle collision avoidance scheme, decision making of vehicle braking control is crucial for emergent situations when safety alerts are not reacted by the driver. In this paper, a novel cooperative vehicle collision avoidance method based on particle swarm optimization is proposed, with an integrated fitness updating criteria considering both safety interval and relative continuity of vehicle deceleration. With a simulation analysis approach, the proposed collision avoiding solution is validated in a real road oriented scenario, and the results demonstrate its effectiveness and advantages to reduce collision and achieve safety assurance under cooperative vehicle infrastructure environment.

Abstract: Considering a UAV has different flight control modes, such as remote control instruction flight and auto-navigation flight, this paper uses modular designing method to describe the overall structure of simulation model, and based on the way of loading waypoint, focuses on discussing the control logic of auto-navigation flight. Furthermore, according to the flight control logic of UAV, the simulation model was built by using Stateflow, and combining with Matlab GUI, the remote control instruction was realized. The simulation results in the auto-navigation flight can effectually verify the correctness of the design of flight navigation strategies and control law. It is practical to build the simulation environment by using Stateflow and GUI technology.

Abstract: The forecasting to future developments of the city fire time series is a challenging task that has been addressed by many researchers due to the importance. In this paper, a Nonlinear Auto-Regressive (NAR) prediction model is applied to forecast the city fire data based on support vector regression. The performances of the NAR prediction model in city fire forecasting are compared with the BP neural network method. The experimental results show that the proposed model performs best.

Abstract: Parallel file systems deploy multiple metadata servers to distribute heavy metadata workload from clients. With the increasing number of metadata servers, metadata-intensive operations are facing some problems related with collaboration among them, compromising the performance gain. Consequently, a file system simulator is very helpful to try out some optimization ideas to solve these problems. In this paper, we propose DMFSsim to simulate the metadata-intensive operations on large-scale distributed metadata file systems. DMFSsim can flexibly replay traces of multiple metadata operations, support several commonly used metadata distribution algorithms, simulate file system tree hierarchy and underlying disk blocks management mechanism in real systems. Extensive simulations show that DMFSsim is capable of demonstrating the performance of metadata-intensive operations in distributed metadata file system.