Applied Mechanics and Materials Vols. 263-266

Abstract: Although there has been some researches about virtual cell manufacturing system, the existing literature lack of discussion about the scheduling model that considering with bottleneck machines in the virtual cells. In view of this deficiency and the new characteristics of the batch splitting problem, this paper considered the batch splitting (or lot splitting) problem in scheduling of virtual manufacturing cells with bottlenecks and multiple machine types, and each of which has several identical machines. In consideration of the hierarchical decision structure of the problem, we developed a bi-level multi-objective mathematical model. Scheduling results and batch splitting strategies of both bottleneck and non-bottleneck machines are given in separate decision levels and additional scheduling objectives are improved in the second model level, while maintaining the maximum use of the bottleneck machine ability. In order to demonstrate how this approach works, application example was shown in this paper.

Abstract: This paper deals with the robust stability problem of distributed systems with interval time-varying delays. The key features of the approach include the introduction of suitable Lyapunov-Krasovskii functional and use of tighter bounding technology. A delay-dependent stability criterion is derived by using linear matrix inequality (LMI) techniques without using either free weighting matrices or model transformation. The criterion can be efficiently solved with available computational software.

Abstract: In terms of characteristics of scheduling problem in multi-varieties and small-batch production mode, three additional constraint conditions including combination constraint, priority scheduling and machine load balance are supplemented based on classical Job-shop scheduling model in order to reflect the actual scheduling activities better. An improved genetic annealing algorithm is proposed aiming at the above model, and the requirement of supplemented constraint conditions is satisfied by means of improving the decoding process of chromosomes. The key technologies of algorithm are discussed in detail. The feasibility and validity of the proposed model and algorithm is demonstrated through simulated computation.

Abstract: This paper is concerned with the robust stability analysis for uncertain stochastic systems with distributed time-varying delays. By using the stochastic analysis approach and free-weighting matrices, new delay-dependent stability condition is established in terms of LMI to guarantee the uncertain stochastic distributed delay system to be robustly asymptotically stable in the mean square.

Abstract: Airfield lighting circuit is an important part of airfield lighting system, and the insulation resistance value of this circuit is affected by humidity, temperature, the quality and the number of the Isolation Transformers and many other factors, so it is difficult to accurately predict the resistance size by using traditional methods. In the light of insulation resistance values of airfield lighting circuit, this paper put forward adopting Gray System Theory to make the prediction, and then build GM(2,1) model to analyze and forecast the resistance values according to the actually measured values of the insulation resistance at Shanghai Pudong International Airport. Finally, the research shows that there is only a little difference between predicted values and the actually measured values. In other words, the prediction of insulation resistance based on Gray System Theory is viable.

Abstract: CFD(Computer Fluid Dynamics) simulation is widely used in IT industry, it usually based on the latest CPU computing power and software technology, can easily take hours even days. A new 3D Navier-Stokes solver based on the SIMPLE algorithm but totally rewritten from ground up with Nvidia’s CUDA software programming API was studied by investigating the use of the latest GPU technology for an electronics cooling problem. The GPU accelerated CFD simulation by using massively parallel algorithm accelerated the calculation by 3.55 times.

Abstract: Aiming at the problem of navigation in unknown environment of autonomous mobile robot, the self-made mobile robot was taken as research object. The integrated navigation technology was adapted to integrate the SLAM navigation system, DR navigation system and MEMS micro inertial navigation system possessed by the studied robot to construct the SLAM/DR/MEMS integrated navigation system of mobile robot. The experiments were carried to test the method, and the results show that the precision of navigation and location of mobile robot was developed by the integrated navigation scheme.

Abstract: In this paper, we use the cone as the model of the warhead to analysis its precession character and target character, which will affect the HRRP (High Resolution Rang Profile) of the warhead. What’s more, we build a model to simulate the situation when the target is observed from multiple line-of-sight (multi-LOS) of radar. After all the research, we come up with an arithmetic that joins precession character and structure character which are based on the multi-LOS time-HRRP. This arithmetic uses all the information that received by radars simultaneously, which can improve the accuracy of the estimation. The simulation experiment indicates the effectiveness of the arithmetic.

Abstract: The micro-Extended-Analog-Computater(uEAC) is a newly emergent unconventional computing model under research and development. Although, a single uEAC unit can achieve some classic pattern classification problem, the slop of the classification face generated by uEAC is a constant and moves parallely. So a feedforward array structure is proposed for the improvement of uEAC, and Particle Swarm Optimizer(PSO) is utilized to configure the uEAC array. The analysis of the mapping characteristics and numerical experiments both illustrate the effectiveness of the improvement.

Abstract: In a Cellular Manufacturing System (CMS), parts based on their similarities are grouped into part families, and are assigned to one or more machine cells to be manufactured. In the design of a CMS, facility layout problem aims to arrange machine cells in the shop floor and facilities in the machine cells in order to have an efficient layout. In this study, a previously developed cellular layout model will be illustrated and validated for a well-known case from the literature. Lingo optimization software version 12.0 and an enumeration method will be used to solve, and validate the model. The results of this study show the validity of the proposed model.