


Vol 50, No 5 (2016)
- Year: 2016
- Articles: 9
- URL: https://journal-vniispk.ru/0146-4116/issue/view/10665
Article
Development of FEA-ANN hybrid model for Equivalent Stress prediction of automobile structural member
Abstract
Chassis serves as a backbone by supporting the body and diverse parts of the automobile. It ought to be sufficiently rigid to endure the shock, twist, vibration and extra stresses. Then, a vital consideration in chassis design is the strength (Equivalent Stress) for sufficient bending stiffness (Deflection). The primary goal of the research is to build up an Artificial Neural Network (ANN) model for identical stress prediction. Two side members joined to a series of cross members to make the chassis frame. The number of cross members and their locations, cross-section and the sizes of the side and the cross members turn into the design variables. The chassis frame model is created in Creo 3.0 and dissected using Ansys. Since, the number of parameters and levels are more, so the probable models are too much. By changing the Parameters, using the orthogonal array the weight of the sidebar is decreased. Then, FEA is performed on those models. ANN model is prepared by using the results of FEA. For training the ANN model, the standard back-propagation algorithm is observed to be the best. A multi-layer perception network is used for non-linear mapping between the input and the output parameters. FEA-ANN hybrid model can save material used, production cost and time.



Distributed control and speed sensorless for the synchronisation of multi-robot systems
Abstract
This paper investigates a synchronization approach to trajectory tracking of networked robotic systems while maintaining time-varying formations. The objective is to control networked robots to track a desired trajectory while synchronizing their behaviors. Combining trajectory tracking and synchronization algorithms, the developed approach uses a cross-coupling technical to create interconnections for mutual synchronization of robots. The main objective of distributed approach is to generate an emerging behavior using only local information interactions. First, a distributed scheme is developed to achieve the networked robots synchronization on undirected graph. Then, the leaderless synchronized tracking problem in the case when only position measurements are available, will be presented. For both cases: In the presence of the velocity feedback or in its absence, the controller, designed by incorporating the cross-coupling technical into a sliding mode control architecture, successfully guarantees asymptotic convergence to zero of both position tracking and synchronization errors simultaneously. The Lyapunov-based approach has been used to establish the multi-robot systems asymptotic stability. A real-time software simulator is developed to visualize the synchronized behaviors. Based on LabVIEW integrated development environment (IDE), a developed human-machine-interface (HMI) allows its user to control, in real time, the networked robots. Simulation and experimental results are provided to demonstrate performances of the proposed control schemes.



Face recognition system based on block Gabor feature collaborative representation
Abstract
Face recognition, one of the biological recognitions, has received extensive concern due to its secrecy and friendly cooperation. Gabor wavelet is an important tool in face feature description. In order to reduce the loss of useful information during down sampling, this work puts forward a Gabor feature representation method based on block statistics, which enhances the efficiency of Gabor feature representation. This study was designed to explore face recognition algorithms on the basis of highly recognizable and real-time collaborative representation. Experimental results indicated that, the face recognition based on block Gabor feature collaborative representation not only guaranteed the calculation speed, but also took full advantage of the robustness of Gabor feature. Besides, the block Gabor feature containing more details further improved the recognition rate.



Optimization algorithm of cognitive radio spectrum sensing based on quantum neural network
Abstract
In recent years, with the development of mobile communications and Wireless Local Area Network (WLAN) as well as restrictions on limited spectrum resources, wireless spectrum resources are increasingly strained. Cognitive radio, put forward as a concept of dynamic use of spectrum, solved the problem of low spectrum utilization rate brought by the current static spectrum allocation scheme and greatly improved the utilization of the existing spectrum resources. In order to overcome the shortcomings of traditional spectrum sensing and improve spectrum detection performance under low signal-noise rate, this paper proposed a spectrum perception algorithm based on quantum neural network (QNN) and carried out an optimization study on the spectrum sensing algorithm of cognitive radio. Through the simulation experiment, we found that the improved QNN algorithm showed more excellent convergence performance and detection capability.



A CDM-backstepping control with nonlinear observer for electrically driven robot manipulator
Abstract
This paper presents a CDM-backstepping strategy for motion control of Electrically-driven manipulator under the conditions of uncertainty and the action of external disturbance, while incorporating a nonlinear observer. Based on this model, a systematic analysis and design algorithm is developed to deal with stabilization and trajectory tracking of elbow robot, one feature of this work is employing the backstepping observer to achieve the exponential stability with position and velocity estimations. The results of computer simulations demonstrate that accurate and robust motion control can be achieved by using the proposed approach.



Autonomous network-based integration architecture for multi-agent systems under dynamic and heterogeneous environment
Abstract
Multi-agent systems fit nicely into domains that are naturally distributed and require artificial intelligence technology. Has been designed an autonomous information services integration architecture based on network to support the rapid changing environments and needs. However, substantial increase of users requests and redirects it may cause the system to unbalance loading and part overloading. This paper proposes an integrated access method by reduces the number of Pull Mobile Agents to reduces the total load of the system in order to achieveautonomous load distribution. In addition, the information structure of integrated service area is effective to improve the ratio of the satisfaction of Pull-Mas (Pull Mobile Agents) with joint request on one node. Through simulation tests show that this system can be guaranteed that services requests and related services requests is uniformly distributed to the nodes of system and ensure that the system load balancing.



Generating optimized gate level information flow tracking logic for enforcing multilevel security
Abstract
Vulnerabilities such as design flaws, malicious codes and covert channels residing in hardware design are known to expose hard-to-detect security holes. However, security hole detection methods based on functional testing and verification cannot guarantee test coverage or identify malicious code triggered under specific conditions and hardware-specific covert channels. As a complement approach to cipher algorithms and access control, information flow analysis techniques have been proved to be effective in detecting security vulnerabilities and preventing attacks through side channels. Recently, gate level information flow tracking (GLIFT) has been proposed to enforce bittight information flow security from the level of Boolean gates, which allows detection of hardware-specific security vulnerabilities. However, the inherent high complexity of GLIFT logic causes significant overheads in verification time for static analysis or area and performance for physical implementation, especially under multilevel security lattices. This paper proposes to reduce the complexity of GLIFT logic through state encoding and logic optimization techniques. Experimental results show that our methods can reduce the complexity of GLIFT logic significantly, which will allow the application of GLIFT for proving multilevel information flow security.



A hybrid method for entity hyponymy acquisition in Chinese complex sentences
Abstract
Extracting entity hyponymy in Chinese complex sentences can be a highly difficult process. This paper proposes a novel hybrid approach that combines parsing with supervised learning and semi-supervised learning. First, conditional random fields (CRF) model is employed to obtain the candidate domain named entity. Pattern matching is then used to acquire candidate hyponymy. Next, predicate and symbol features, syntactic analysis, and semantic roles are introduced into the CRF features template to identify the hyponymy entity pairs. Finally, analysis of both the parallel relationship of entities among sentences and entity pairs in simple sentences is conducted to obtain the hyponymy entity pairs in Chinese complex sentences. The experimental results show that the proposed method reduces the manual work required for CRF markers and has an improved overall performance in comparison with the baseline methods.



Research on the location of acoustic emission source of rock breaking point by using phase difference method and Geiger algorithm
Abstract
Geiger iterative algorithm is very strict to the initial value. If the initial value is not selected suitably, it is difficult to enter the convergence range, thus increasing the number of iterations. The acoustic emission source location based on phase difference time delay estimation method reduces the error of acoustic emission location, but it has some shortcomings in accuracy. Based on the above problems, this paper presents a new algorithm for Geiger optimization based on source localization. Firstly, the initial value of Geiger is obtained by using the phase difference method. Then, the optimal solution is obtained by the iterative solution of Geiger algorithm and the least square method. The simulation results show that this method can effectively solve the problem of selecting the initial value of Geiger, so that it can quickly enter the convergence range, improving the convergence speed and positioning accuracy, comparing the positioning results of the United States PCI-2 type acoustic emission instrument, the average error reduced by about 5 mm.


