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For the problem with imprecise optimal solution and reduced convergence efficiency of basic artificial fish swarm algorithm (BAFSA) in the late, the adaptive enhanced prey behavior of artificial fish and the segmented adaptive strategy of artificial fish’s view and step were designed. The hybrid adaptive artificial fish swarm algorithm (HAAFSA) was structured by the adaptive enhanced prey behavior and the segmented adaptive strategy of artificial fish’s view and step, which have been verified on research. According to the characteristics of the coalmine rescue environment, the path planning environment model was established in two-dimensional plane and the optimization constraints conditions were disposed by detecting the distance between path sections and barriers. The HAAFSA was applied to coalmine rescue robot path planning. Simulation results showed that the HAAFSA could improve the performance of the optimal path.

With the recently rapid development of information technology (IT), new synergies have been created by developing a variety of converged services which integrate information technology environments with a variety of fields. In the proposed method, a vessel’s navigation information is received from wide-range sensor systems, and its distance from the anchorage is measured by using spherical trigonometry. When the measured distance is not within the anchorage error threshold defined by the vessel traffic controller, there will be additional voice communications.

In the present paper, the problem of finite time convergent guidance law design is investigated and a novel guidance scheme with finite time convergence is presented. To improve robustness of the guidance system against highly maneuvering targets, two robust nonlinear techniques are mixed, integral sliding mode and finite time backstepping control. The control loop dynamics are considered as a first order transfer function due to their significant contribution to the guidance loop stability. Furthermore, this guidance law makes the line-of-sight (LOS) angular rate converge to zero in a finite time, before final time of intercepting process. The proposed law is compared to terminal sliding mode guidance law and its superior performance is shown through simulation.

Rhythmic movements show fundamental motion patterns in the locomotion of animals. Inspired by real animals, biomimetic robots also adopt similar locomotion pattern in order to obtain versatile mobility. For the motorized mechatronic systems in robots, trajectory tracking control of rhythmic motions is a challenge because periodical friction and other un-modeled dynamics may exist and they bring disturbance to the system. In order to enhance the tracking performance, a robust tracking controller for a biomimetic fish robot is discussed in this paper. The disturbance and the command signal will be modeled in the controller design. The controller can yield theoretically zero tracking error to a sinusoidal command input. The formulation of the controller and experimental results are presented in the paper.

Hydraulic automatic gauge control (AGC) is a very important part of rolling mill for magnesium plate rolling. The control effect of automatic gauge control system influences the quality of the rolled product directly. AGC system is an essentially nonlinear, time delay, time-varying, large inertia, multivariable and coupling complex system, which increase the designing difficulty of control system. Based on the mathematical model of the automatic gauge control system, a simulation platform of rolling mill is set up, and a sliding mode variable structure controller is designed to realize position control for the hydraulic automatic gauge control system. The control effect of the proposed sliding mode controller is compared with that of a general PID controller whose parameters was adjusted by Ziegler-Nichols method. Simulation results show that the sliding mode controller has strong anti-interference ability and can give satisfactory control effect.

Recently, Compressive Sensing (CS) has been applied to array signal processing. In theory, Direction-of-Arrival (DOA) estimation based on CS recovery can work well in correlated environments. However, a large number of sensors (i.e., linear measurements) are still needed for CS recovery. To improve on this, we propose a new CS-based DOA estimation method with a recently designed antenna structure called the Asymmetric Antenna without Phase Center (Asym-AWPC). The best reconstruction is achieved by solving the l1-norm optimization problem, which is cast as an l1-regularized least-squares program. Simulated results indicate the effectiveness of the proposed CS-based Asym-AWPC DOA estimator in a multipath environment over a recent Asym-AWPC DOA estimator but using the Multiple Signal Classification (MUSIC) rather than CS. Further improvement on the resolution can be achieved by tuning the degree of asymmetry in designing the Asym-AWPC.

This paper investigates the global asymptotic stability for the Cohen-Grossberg neural networks with time-varying delays. By constructing suitable Lyapunov functional and employing the nonsmooth analysis, some sufficient conditions are obtained without demanding the boundedness and differentiability of the activation function. Moreover, one example is demonstrated to illustrate the effectiveness of the proposed criterion.

The matrix factorization algorithms such as the matrix factorization technique (MF), singular value decomposition (SVD) and the probability matrix factorization (PMF) and so on, are summarized and compared. Based on the above research work, a kind of improved probability matrix factorization algorithm called MPMF is proposed in this paper. MPMF determines the optimal value of dimension D of both the user feature vector and the item feature vector through experiments. The complexity of the algorithm scales linearly with the number of observations, which can be applied to massive data and has very good scalability. Experimental results show that MPMF can not only achieve higher recommendation accuracy, but also improve the efficiency of the algorithm in sparse and unbalanced data sets compared with other related algorithms.

In this paper, the problem of short-term load forecasting is divided into load classification and forecasting. Load classification is needed to obtain meaningful load data as input to train forecasting models. To this end, k-NN and K-mean algorithms are presented. K-mean and k-NN algorithms can handle seasonal load classification and daily load classification, respectively. The classified load data are used to train forecasting models, which are Artificial Neural Networks, Simple Exponential Smoothing, and ARIMA models. As a real case study, we tried to forecast the electric power load of the Republic of Korea. A comparison between the classified and non-classified load forecasts demonstrates the efficiency of the proposed method.

In space exploration, robots are important to do some hazardous jobs instead of human. The robots usually work in an unstructured environment to operate non-cooperative targets. There are unpredictable events which can reduce the capacity of robots. And unfortunately the communication channel between robots and ground command center has limited band-width and high latency. Therefore, space robot system needs plans that can autonomously deal with unpredictable events. Executable plans must satisfy some well defined conventions. This paper proposes a formal representation of plan library based on Petri net as well as the way to define conventions based on LTL. The formal representation formalizes concepts such as event, action and behavior. And plan is a behavior instance. This approach could be used to generate rational plans automatically or with a litter help of human. We illustrate them with a space robot application example.

A sliding-window modeling approach of neural network (SWMANN) was presented. The basic idea is that training data for neural network should be reconstructed by means of a slide-window way to build input and target samples. It means that the output is determined not only by the current input, but also by the past input, which could better follow the dynamic change and development of real systems. In this paper, SWMANN was introduced. A detailed theoretical derivation was described for its implementation by taking wavelet neural network as a modeling tool. Moreover, SWMANN was compared with classical modeling approach of neural network (CMANN). Theoretical results indicated that CMANN is a special case of SWMANN when sliding-window parameters are selected as 1. Therefore, compared with CMANN, SWMANN presented in this paper is a more general form.

For a train’s safe operation, a braking system is necessary to control its velocity easily and fast. A braking system is classified into mechanical braking, which transforms kinetic energy into heat, and electric braking, which transforms power energy into heat. A braking resistor is used to suppress the increased voltage and absorb the regenerative power. Regenerative braking system dissipates the regenerative energy generated by electric braking in the load resistor and suppresses the excess voltage of the power electronics system. In this paper, a method to design the electric braking resistor of a roof-type electric braking system used for railway carriage is proposed by the use of thermal analysis. Through thermal analysis, the shape and arrangement of an element, which is the main part of a braking resistor is designed. The verification of the designed values is conducted by experiments on the developed electric braking resistor. The experimental result for the maximum temperature of the element is 603.8ºC, which deviates 1.3% from the designed value.

Process modeling is an important task for collaborative design of a multi-disciplinary nature. This paper proposes an ontology-based method to model the collaborative design process. The aim is to effectively coordinate, allocate and share design resources. Concepts of task, sub-task, and local ontology in the collaborative design environment are defined. The tasks of achieving optimal resource allocations of design resources are divided into sub-tasks that are stored in the form of local ontology. Genetic algorithm is employed in match-researching among local ontology and different disciplines. Tasks and their discipline views are described in the ontology-enabled semantics-sharing of design resources in multi-disciplinary collaborative design. Process modeling of a missile is used as an example to demonstrate the capabilities of the proposed method and framework.

Aiming at the lower automation, accuracy and efficiency of the domestic band sawing machine, this paper studies the real-time detection technology based on the sawing load, and develops the digital control system of the constant power sawing with the micro-feed performance to improve the load imbalance of the band saw blades in the sawing process.

Signal transmission analysis is performed for a serial advanced technology attachment (SATA) cable assembly using a three-dimensional (3D) electromagnetic field simulation. In this work, SATA cable assembly consists of the connector, PCB and cable in series. Three components and their assembly are investigated with their differential mode S-parameters. Also, the insertion loss, reflection loss and differential impedance of the components are calculated to analyze their signal transmission characteristics. Each component has approximately 100  of the differential impedance. However, their high-frequency responses such as insertion loss and reflection loss show different characteristics. While the connector and cable present the excellent signal transmission performance, the printed circuit board (PCB) has lower characteristics despite the shortest trace length. The insertion loss and reflection loss of SATA cable assembly are investigated and have a similar tendency with those of the PCB. These results verify that signal transmission properties of the SATA cable assembly are affected significantly by the PCB with the largest loss.

Spray gun trajectory optimization of spray painting robot is highly desirable for today’s automotive manufacturing. Sometimes, the way of many-times spray painting is used to meet the technological requirements. In this paper, a new spray gun trajectory optimization method of many-times spray painting for the plane has been developed after complex surface partitioned. Based on the spray gun trajectory optimization of one-time spray painting, the method utilizes the coating thickness superposition cycle and status number to establish the coating thickness superposition model for many-times spray painting and to optimize the spray gun trajectory of many-times spray painting. The number and cycle of coating thickness superposition status are developed to modeling the coating thickness distribution model for many-times spray painting. The coating thickness deviation from the required coating thickness is optimized by modifying the offset distance between the subsequent spray gun trajectory and the first spray gun trajectory. The results of simulations have shown that the spray gun trajectory optimization of many-times spray painting achieves satisfactory performance, the coating thickness uniformity satisfy high standard requirement.

Vibration characteristic of mechanical system is the main factor affecting machine tool accuracy and longevity. The HTM50200 CNC with eight axles and double five-axis linkage was tested by a self-made vibration test system. The dynamic characteristic and fault diagnosis was analyzed by using the method of cepstrum identification on the vibration signal of X, Y, Z direction of the principal axis front. Analysis shows that the machining center has good dynamic characteristics, and has no obvious potential problems; the machining center is greatly influenced by Spindle cutter handle system; obtain the optimal processing parameters for machining center.

Compressed natural gas has various advantages as an automotive fuel compared to that of gasoline and diesel. Natural gas is economical, has better knock resistance, a wider range of flammable air fuel ratio, as well as lower carbon monoxide, carbon dioxide and hydrocarbon emissions.In CFD calculation, the comparison with optical data shows a good agreement in terms of jet penetration and overall evolution for all the cases examined here. From these results, CFD proves to be a useful tool to optimize injection against environmentalparameters and nozzle configuration in order to increase efficiency and reduce the emissions in a CNG-fuelled DI engine.

The precise control of mobile robot is an important issue in robotics field. In this paper, the motion model of mobile robot is established by mechanism analysis. Then, a fuzzy PID controller is designed for trajectory tracking of mobile robot. The controller consists of a PID controller and a fuzzy inference unit with two inputs and three outputs to tune the parameters of PID controller according to the error and error rate. Finally, the model of a four-wheel mobile robot, fuzzy PID and traditional PID controller are all simulated in Simulink. Simulation experiments are reached in different conditions. The result shows that the mobile robot with the fuzzy PID controller can track the desired trail by about 3 seconds in advance and the overshoot of the system will decrease by 40 percent, comparing to the mobile robot with the traditional PID controller. The advantages of fuzzy PID controller for trajectory tracking control of mobile robot are major in its rapidity, stability, anti-interference and tracking precision.

In this research we propose a miniaturized dual electromagnetic oscillatory actuator. The proposed actuator is a moving magnet type voice coil actuator with two rotating parts. The structure of the actuator is simple, which includes two magnets, a coil, and a yoke. We provide a linear model to characterize the actuator. We then determine torque and restoring constants using finite element simulation. We also present the dynamic characteristics of the actuator. We propose several types of legged locomotion using dual electromagnetic oscillatory actuators, which is demonstrated and verified using our legged robot prototypes.

We propose a practical camera calibration system on mobile platforms to calibrate the camera’s intrinsic parameters, based on the geometrical property of the vanishing points, which are determined by two perpendicular groups of parallel lines. In this system, first, we detect and cluster the lines of the input images to compute the vanishing points. Then, we establish the intrinsic parameter constraint equations based on the perpendicular property of the vectors that connect the optical center and the vanishing points, and solve them using the least squares method. This system only requires the camera to observe a rectangular card shown in a few (at least four) different orientations. The experimental results of real images show that the proposed calibration system is robust, simple, and practicable.

The piston stop position is crucial for instantaneous reverse starting method in idle-stop system. It is very difficult to control the piston stop position. In this paper, the relationship between the piston stop position and the air inflow is set up. Then the piston stop position control problem is converted to the electronic throttle control problem. A feedforward-feedback controller for the piston stop position of the GDI engine is proposed. The feedforward controller is spring compensator and friction compensator, which can eliminate the nonlinearity error of throttle system. The feedback controller is backstepping controller which is adaptive for a class of nonlinear processes. The simulation results show that the composite control law enables the throttle opening to track input orders quickly and accurately. And there is no overshoot.

This paper designs a tour scheduler for electric vehicles (EVs) which want to visit multiple places including V2G (Vehicle-to-Grid)-enabled buildings. During a tour, an EV consumes energy, has its battery charged, and even provides (or sell) redundant electricity to a microgrid, which can avoid consuming expensive peak-rate energy from the power vendor. To find an efficient schedule for a set of user-selected destinations, relevant criteria on tour length, waiting time, and earned reward are calculated to evaluate the fitness of each schedule. Moving EVs can achieve temporal and spatial load shift, necessarily allowing collaboration between independent microgrids separated mainly due to security reasons and technical problems. With the definition of fitness functions, our scheme traverses the search space consisting of feasible tour schedules. The performance measurement result shows that the sales amount maximization improves the amount of electricity sold to a grid by up to 85.6 %, compared with the waiting time minimization scheme. Additionally, tour length minimization generally achieves reasonable performance due to the reduced tour length and battery consumption.

For the influence of time varying parameter on servo accuracy of electro-hydraulic position servo system, nonlinear robust adaptive controller with the ability of restraining the parameter perturbation for symmetry valves-control symmetry cylinder system is put forward which is based on the Lyapunov stability theory, The nonlinear state equation of symmetry valves-control symmetry cylinder system was derived, and the controller design process was given. the control strategy was verified on Co-simulation of MATLAB & AMESim and semi-physical simulation platform respectively, the simulation and experimental results show that the tracking performance of electro-hydraulic position servo with nonlinear robust adaptive controller meet the double ten index, and verify efficiency of the method presented through simulations.

To solve the "soft field" effect and the ill-posed problem in electrical capacitance tomography technology, a novel image reconstruction algorithm based on population entropy and adaptive differential evolution for Electrical Capacitance Tomography is proposed in this study. The algorithm uses all the gray pixels as the initial population’s individual. After finite iterations, the algorithm mutates and makes crossover of the population in order to obtain the optimal species populations. That is the optimal value for the ECT imaging pixels. The population entropy and the variation factor make the range of each searching generation decreasing. In the simulation, the improved adaptive differential evolution algorithm will be compared with the LBP algorithm. The result shows that the new algorithm has better image quality and more stable boundary than the LBP Algorithm, which provides a new way to reconstruct images for ECT.

It may be difficult to request an emergency rescue with a mobile communication handset in a sealed space like an elevator in the case of an emergency situation, due to electromagnetic waves shielding within the elevator. The call button installed in an elevator is mostly connected with management office or security room, and a problem that immediate rescue becomes difficult arises during the absence of an administrator or a guard. In this context, the development of a technology enabling to request rescue to the administrator or guard even during his/her absence is required. This paper enables location information to be sent via SMS and phone call to the mobile phone of the person concerned registered with the emergency call management system immediately, if someone presses the emergency call button in an elevator.

Junction surface characteristics is one of the many factors influencing the performance of machine tool. It is also a major source of machine tool contact stiffness and damping. Study on the junction surface characteristics of this machine is very important to improve the performance of the machine and the machine structure optimization. According to the similarity theory, this paper will small guide rails are used as scale model, research on small rail junction surface characteristics and combining the conclusion extended to heavy machine tool surface. This paper from the geometric similarity and dynamic similarity surface on the comparative analysis of the small rail and heavy machine tool guide rail with two aspects of similarity theory, after verification, proof of small guide surface and heavy machine tool guide surface similarity.

A new tracking algorithm is proposed for strong-maneuvering target, which is based on a two-layer nested model with Improved Current Statistical (ICS) model and Curvilinear (CL) model as the inner and outer layer respectively. The inner layer use ICS model to construct statistics with filtering residuals to detect target’s maneuver and thus correcting the parameters of CS model in real time in order to adapt to target’s real motion. The outer layer uses the estimate of acceleration obtained from the inner layer as its input and in this way conduct better performance of target tracking by taking advantage of CL model, which can better correspond to the curvilinear motion of target. Simulation results show the practicability of the algorithm proposed in this article and demonstrate good tracking performance.

The previous PDA based wireless meter reading system uses the method of transmitting the meter value of the gauge using the PDA meter reader when instructed by the PDA meter reader. Such meter reading methods requires a considerable amount of time when collecting the data from multiple collectors. This paper will propose the structuring of new meter reading system (Mobile OMR) and meter reading infra (Mobile Dongle) in order to overcome the limits and disadvantages of the previous PDA wireless meter reading system using the smart devices that can directly communicate with the remote meter reading system and the mobile dongle that can be linked to the smart devices. In addition, by utilizing the many features of smart devices and to solve the problems of timely/costly occurrence of installing wireless meter reading system, meter reading and maintenance, it was configured to enable the selection change of each devices and immediate meter reading operation test directly at the site according to the situation of the site where the remote meter reading system is installed. In addition, by using the smart devices, a user authentication technique to solve the security issues on the use of application was proposed, and through the GPS and map function, the location information of installation site of each devices were accurately mapped in order to allow the convenience in management of location information on the installation site of all devices, and by receiving the log data or status information stored in the remote meter reading system in high speed, it intends to provide the installation check, meter reading and maintenance methods of remote meter reading system using the smart devices and mobile dongle that can enable to recovery of data during the failure period and reducing the maintenance time.