Earticle

In order to solve the problems of traditional smoke sensors which include disposable detection, high false alarm rate and low response speed, a new smoke detection sensor used in the early fire is proposed in this paper. Infrared photoelectric detection circuit is designed based on the light extinction principle to detect smoke concentration. Based on the analysis of fluid dynamics, the detection cavity and the miniature centrifugal fan are designed not only to realize the rapid and continuous detection, but also to reduce the error of the next detection. The quantitative detection model of smoke concentration is established with the method of smoke equivalent, which is verified through experiments. According to the multiple quantitative values, the control system can judge the level of smoke concentration and control the corresponding alarm circuit to warn users. The result shows that the error of the quantification standard deviation is below 3.47 percent, which indicates the designed smoke sensor in this paper can realize the continuous online quantitative detection under the unsaturated state of smoke concentration.

In this paper, an LQ-servo design method based on reduced order observer is proposed in order to control the two-wheeled self balancing robot. We employ reduced order observer, which estimates the states that cannot be accessible by the direct measurements from sensors in order to make its implementation on real time digital processor simpler and cost-effective. The performance index of LQ-servo controller is determined such that overshoot and oscillation of the controlled system in time domain are minimized. The effectiveness and performance of the proposed control system are shown via numerical simulations. It is also shown from hardware-in-loop simulator that the proposed design for self balancing robot reflects the real time behavior quite well.

The phase-shifted full bridge zero voltage soft switch (ZVS) topology of 2.2KW electric operation power supply is analyzed in brief. Then, parameters of main circuit are designed and selected. At the same time, the high frequency transformer and the oscillatory inductor are manufactured. According to the actual characteristics of electric power supply, the power MOSFET and the second rectifier-diode are chosen. By waveform analysis, temperature and power efficiency test, the experimental results confirm the reasonableness of the design.

A new kind of adaptive backstepping method is proposed for simplified missile model of pitch channel with time-varying and uncertain parameters. Backstepping control is an effective method for coping with system uncertainties. Adaptive method is integrated with backstepping method and a Lyapunov function is constructed to guarantee the whole system is stable. Through the theoretical analysis and numerical simulation, comparison between PID control and backstepping control shows that the backstepping control for the uncertain missile system has a better control effect. And compared with the PID control method, backstepping control has better robustness.

Least association rules are related to the rarity or uncommonness relationship among itemset in database repository. However, mining these rules are quite tricky and seldom discussed since it usually includes with infrequent items or exceptional cases. In manufacturing industry, detecting these rules is very useful and exciting for further analysis such as for market segmentation, prediction, and product arrangements. In this paper, we introduce an enhanced association rules mining method, called Significant Least Pattern Growth (SLP-Growth) and a new measurement named Critical Relative Support (CRS). The novelty of the proposed method is that unlike existing methods, it is used for capturing interesting least items from line-off database. The data which comprised of production of motorcycle/scooter is taken from Malaysia national motorcycle manufacturer called Motorsikal dan Enjin Nasional Sdn Bhd (MODENAS). The results from this research provide useful information for the management to understand the customer demand trends comprehensibly, and enable them to design marketing strategy accordingly.

In this paper, a hierarchical nonlocal method for image segmentation is proposed. The method is mainly consisting of two stages. In the first stage, a nonlocal segmentation model based on nonlocal differential operators is used to find a smooth solution. Once the solution is obtained, the segmentation is done by thresholding the solution into different phases in the second stage. The K-means method is used to determine the thresholds. One can obtain any K-phase segmentation ( K ³ 2 ) by choosing ( K - 1 ) thresholds. There is no need to specify the number of segments before finding the solution. Due to the convexity of our proposed model the split-Bregman algorithm is adopted to efficiently solve the minimization problem. When the images are severe intensity inhomogeneity, a nonlocal variation Retinex algorithm is used to preprocessing the given images. The true underlying reflectances of the given images are extracting. Then, these reflectances are used as inputs to the proposed nonlocal model. Experimental results show that our method performs better than many two-phase or multiphase segmentation methods. With the preprocessing of the nonlocal variation Retinex algorithm, our method produce better results and is more efficient than many famous local region-based active contour model (ACM) methods for images with intensity inhomogeneity.

In this work, metal ion implantation was employed to improve the mechanical properties of Al2O3/polytetrafluoroethylene (Al2O3/PTFE). Four metal ions (Al, Cr, Ni, and Ag) were selected as the implantation source, respectively, and the implantation process was optimized by SRIM method. Optimization results revealed that, among these four metal ions, implantation of Al ions exhibited the best modification for Al2O3/PTFE composite layer, when the particle distribution section, distribution range and energy exchange were concerned. Al ion implantation could minimize the damage of carbon skeleton and lamellar structure of Al2O3/PTFE substrate, which kept strong scattering of Al ions and obtained the thick and uniform coating on the surface of Al2O3/PTFE substrate. The uniformity of Al2O3/PTFE layer was improved with the increase in Al ions implantation dosage and the best dosage of Al ions was regarded as 1×1016 ions/cm3 with the implantation energy of 20KeV. After implantation modification, the mechanical properties of Al2O3/PTFE layer were obviously improved. The hardness (H) of samples was detected to be 0.65GPa and elastic modulus (E) 2.2 GPa, with a higher H/E value of 0.295, which was 10 times higher than original PTFE.

An adaptive backstepping controller is proposed for a class of nonlinear systems with hysteresis and unknown control direction. As the unknown gain sign is combined with multi-valued non-smooth hysteresis together, it is more challengeable to mitigate hysteresis effects and meanwhile guarantee stability of the dynamic systems. In this paper, Bouc-Wen model is adopted to describe the hysteresis. Then RBF neural networks are applied to approximate the unknown functions. The unknown control direction is solved by Nussbaum function. The adaptive backstepping controller is developed using prescribed performance function to confine the error to a predefined residual set. It is proved that all the closed-loop signals are bounded and the tracking error converges to an arbitrarily small field. Finally, the simulation result shows the feasibility of the control scheme.

This paper presents a decoder with enable input. This decoder is developed using quantum-dot cellular automata (QCA). QCA opens a completely radical way of microelectronics development and a potential replacement of CMOS based electronics. It ensures highly compact circuits, faster processing speeds, low power consumption. The use of clock in QCA provides power gain which is an important feature and this feature is not available in CMOS electronics. The proposed decoding architecture is designed using 5-input majority gate to keep a regularity so easily extendable for 3:8 or 4:16 decoders and also easy to connect with other circuits.

In this paper, we consider the dynamical model of a class of underactuated systems. By combination of the partial fedback linearization and Yamada’s global linearization, we deduced a global approximate linearization method for underactuated systems. By using this method, the dynamical equations can be transformed into an state eqution that is expressed as a pseudolinear term with Brunovsky canonical form plus a high order nonlinear term, where the nonlinear term is high order on the equilibrium manifold of the system. By standard nonlinear feedback method, the system is transformed into the sum of a stable linear term and a high order nonlinear term. Take proper feedforward value as the input to reduce the influence of the nonlinear term to the system and thus the underactuated system can be regulated. This method is applied to the ball and beam system and simulation results show that the proposed approximate linearization method is effective for setpoint control.

Against EMLA (Electromagnetic Linear Actuator) in the long-running, the changed parameters of actuator coil resistance and inductance caused by temperature rise resulted in degradation of control performance, and parameters recondition in the inverse system control program. By using parameter identification method based on recursive least squares method (RLSM), the adaptive inverse system control is implemented in electromagnetic linear actuator. Under Matlab/Simulink it establishes the simulation model to simulate online identification process and the adaptive inverse control system strategy which achieve the control effect when the parameters change, and the test data are identified off-line verification. The results show that it is able to accurately identify the actuator coil resistance and inductance parameters, and at the same time, it can identify system’s dynamic mass, viscous friction coefficient and disturbance force of load. Finally, the test platform was built to verify, the identification results was used to control parameters online real-time. And the parameters identification was used in the practical application of inverse system control, implemented system’s adaptive control, improved system’s robustness in long run.

Maintenance consists of several actions which are performed on a given component to improve its dependability and performance, and subsequently that of its overall system. Maintenance policies are advocated for consideration right from the infancy stage of system design. However, existing systems or legacy systems may not have been designed with maintenance in mind. Additionally, the data required to carrying out the improvement analysis of such systems may not be available. Therefore, it is helpful to investigate how the dependability of existing systems could be improved and this is the focus of this paper.

As we all know that the heading control of unmanned surface vessel (USV) is often with complex nonlinearity and uncertainty, it is difficult to establish accurate mathematical model, so the conventional control algorithm which is applied to linear system has some limitations. As fuzzy control does not rely on the specific mathematical model, and with control robustness, it is widely used in motion control system. However, the conventional fuzzy control is not high accuracy, usually with a large overshoot and steady-state error. In order to improve the dynamic and steady-state performance of fuzzy controller and further more improve its control quality, this paper combined expert system and fuzzy control then constitutes the Expert-Fuzzy controller, and applied to the heading control system of USV, simulation results shows that Expert-Fuzzy control system can achieve better heading control performance of USV compared to conventional fuzzy control system.

MUSIC algorithm has often used to solve the direction of arrival estimation problem to take advantage of the benefits of beamspace operations, such as reduced computation complexity, reduced sensitivity to system errors, good resolution, reduced bias in the estimation. In this paper, a variant of the beamspace MUSIC algorithm is developed, taking advantage of unitary transformations. In general, the beamspace MUSIC algorithm improves direction of arrival estimation by using reduced order characteristic polynomial rooting though Gaussian column reduction. The unitary beamspace MUSIC algorithm reduces the computational complexity of MUSIC algorithm by using real valued forward and backward, while maintaining the original precision. We use forward backward spatial smoothing technique as the preprocessor of beamspace MUSIC algorithm to recover the reduced rank of the covariance matrix due to the coherence of source signals. Through computer simulations show that the combination of spatial smoothing a beamspace MUSIC can achieve good resolution performance.

In this paper, an improved adaptive monopulse scheme based on modified projection approximation subspace tracking deflation (MPASTd) approach is proposed. Owing to the fast convergence speed of MPASTd for recursively estimating the interference subspace, the proposed algorithm can obtain the formula for adaptive monopulse ratio calculation by a subspace projection. Therefore, it is able to accurately estimate the source location using less training data and reduce the computational complexity significantly. The effectiveness and fast convergence speed of the proposed method is verified by simulation results.

Actions in some systems are disordered. But IP-secure and TA-secure can't fit the disordered system. This paper proposes completely purge secure to deal with the problem. The function cpurge proposed can purge all actions which directly or indirectly interference the domain which can't be done by the function ipurge and TA.

In this paper author want to present new algorithm and recommendations for setting distance relay protection. This algorithm bases on technical effect criterion with using probability statistical method. Main approach is to study and develop technical effect criterion for selection of differential relay protection setting and technical efficiency criterion for estimating this setting. The probability statistical algorithms are used to calculate the above criteria.

Numerical simulation was conducted for fluid flow past a circular cylinder with triangular control rod in the upstream at low Reynolds numbers. The study focuses on the influences of leg length of rod L, rod-to-cylinder spacing ratio S, vertex angle of triangular α of rod on the vortex shedding and forces. The results show the equilateral triangle rod in the upstream takes effective suppression of not only the lift but also the drag in the range of 0.2R≤L≤0.5R and 3R≤S≤6R(R is the radius of circular cylinder), and the vortex shedding between the two cylinders maybe lead to sharp increasing of the force on the circular cylinder.

In order to avoid the problem that cables are divorced from constraints during spacecraft launching, rules of nonlinear vibration behavior of laying cables need to be analyzed, so the common restriction condition of cables inside the spacecraft is selected to study. Based on the inertial coordinate system of cables, force on the cable element is analyzed with elastic mechanics, and then the vibration model of cables with coupled constraints can be obtained. And then, with the application of boundary conditions, the vibration model of spacecraft cables with longitudinal load is obtained, and vibration ordinary differential equations of cable with longitudinal load are obtained by using the Galerkin method. Further, the vibration response of cable with one end effected by longitudinal disturbance is obtained along with the nonlinear vibration model of cables with coupling constraints calculated and analyzed by using the numerical method. The results show that mechanic properties and the reliability of work of cables can be improved by using local constraints on the laying path of spacecraft cables properly.

In this paper, we proposed the intersection collision avoidance (ICA) algorithm for bicycle to vehicle (B2V) safety service and analyzed its performance by using ‘PreScan’ and ‘MATLAB’. As typical type accidents related with bicycles, we consider the bicycle to vehicle (B2V) communication. The derived analytical approach can explain the condition and effect of bicycle collisions. Furthermore, proposed algorithm has been confirmed by simulations. Consequently, the ICA developing methodology is verified to be used as a general tool to reduce the cost and the time consumption required for commercialization of safety services under IEEE 802.11p/wireless access in vehicular environments (WAVE) wireless networks.

According to the DCT structure and principle, the dynamic shifting process of DCT has been analyzed, and the engine and clutch model have been established. The driver intention has been analyzed and distinguished through the fuzzy control theory, on this basis, gear shift rule has been formulated based on driver intention，separately from the power performance and economy performance. Clutch and engine control strategy for DCT shifting process have been proposed, and shifting control logic also has been drawn up. DCT shifting simulation model has been established based on the MATLAB/Simulink software simulation platform. The simulation result shows that the shifting simulation model in this study meets the requirement, and the shifting control strategy has a good control effect.

In order to investigate the impact of the optical illusion deceleration marking width on the change of the driver’s heart rate, the comb-tooth deceleration marking was employed as an example and fourteen drivers were tested through indoor simulation at the selected width of 20-50 cm. The changing rate of drivers’ heart rate was used as an indicator to evaluate the safety and comfort of the width of the optical illusion deceleration marking and then the regression model for the two was established. The results showed that on the road section with the operating speed of 80km.h-1, the drivers were getting more and more nervous and the absolute value of the changing rate of their heart rate was bigger and bigger with the increase of the marking width. Take the heart beat change rate of 20% as the threshold value of drivers’ tension and the safety and comfort of the width and calculate it based on the logistic regression model, it showed that the most favorable width of the deceleration marking was 42 cm. Under the same condition, the second round of test was conducted at the operating speed of 40-120 km.h-1. The drivers’ view was narrowed and vision was decreased with the increase of the operating speed, at this time, the drivers got even more nervous and the changing rate of heart rate increased accordingly.

With the explosion of wireless technologies, variable types of mobility are presented. To provide seamless communication and mobility management, IP based mobility management protocols are proposed. One of them, to provide inter/intra/inner vehicle communication, the vehicles’ mobility management is studied that called VANET (vehicular ad hoc network). However, the mobility of vehicular results in short lived connections to access router (AR), affecting the availability of IP services in VANET. The most critical issue consists of the design of scalable routing algorithms that are robust to frequent path disruption caused by vehicles' mobility. With the navigation information that one of vehicles’ mobility features, we are classified into intra highway mobility and global mobility management mobility. Furthermore, we propose efficient mobility management scheme based on route prediction in VANET. Experimental analysis shows that proposed mobility management protocol reduces handoff latency, signaling costs and packet loss.

The underwater hovering of submarine is to keep and alter depth at zero speed, which is a complex nonlinear process. Traditional control methods affect the effect because of lacking of adaptive capability, while fuzzy control can solve the problem well. Here the structure of fuzzy controller was set up based on the principle of fuzzy control. Then the rule for hovering control was carried out according to the classic step response. At last, the anti-jamming differentiator was set up by Simulink. The result of two basic working condition simulation showed that fuzzy controller was able to fix the submarine depth well, and had the advantage of fast and robust.

This paper presents a mathematical model of an inventory system from the warehouse of goods Distribution Company using system identification approach. Considering items ordered from suppliers and items shipped to customers, as the inputs of the system and the stock level as the output system. In this paper, ARX model and ARMAX model are outlined and compared. The performances of each type of model are highlighted. A case study with real data set is discussed.

An infinite-horizon optimal control problem for the deployment of a tethered sub-satellite under complex nonlinear constraints is presented. The nonlinearities in the system model and the constraints of states and control are taken into consideration. Legendre-Gauss-Radau pseudo spectral method is described for solving the infinite-horizon optimal control problem numerically. By using a smooth, monotonic domain transformation technique, an infinite-horizon optimal control problem is approximated with a finite-horizon problem. The resulting problem in the finite interval is transcribed to a nonlinear programming problem. The proposed methods yield a series of approximations to the state on the entire horizon. The optimal control law can be determined via a nonlinear programming, without any iteration. A numerical example is included to demonstrate the high effectiveness and hard real-time of the proposed schemes.

This study explores the effect of consumers' prior smoking attitudes and persuasion knowledge in the effect process of corporate social responsibility communication. Preceded by a pilot study, a survey of consumers' perception is conducted toward a mobile CSR application. First, consumers' prior smoking attitudes and persuasion knowledge are revealed to have interaction effect on reputation of the tobacco company. Second, interactivity of the branded content and consumers' persuasion knowledge have interaction effect on the perceived authenticity of the company. Toward reputation, interactivity of the branded content and consumers' persuasion knowledge have no significant interaction effect, but the level (high/low) of branded content has a direct effect on reputation. Practical implications, limitations and future study directions are discussed.

Piezoelectric ceramic actuators have wide application prospects in precision positioning and measurement technology, but its hysteresis characteristics cause a lot of restrictions to their applications. To solve this problem, this paper summary the hysteresis characteristic of piezoelectric ceramics, and collect the data through the experiment, analyze and research the piezoelectric ceramic hysteresis curves at different excitation signal effect, and the fitting curve is got based on the experimental data in order to establish hysteresis model of piezoelectric ceramic actuators by using of the curve fitting toolbox of MATLAB. Then the inverse model is obtained and the inverse compensation feed-forward control algorithm is proposed. The experiment results show that the piezoelectric ceramic actuators meet the basic linear relationship between the input voltage signal and the output displacement, and eliminate hysteresis nonlinear of the piezoelectric actuators.