Earticle

MAV (Micro Aerial Vehicle) is nonlinear plant, it is difficult to obtain stable control for MAV attitude due to uncertainties. The purpose of this paper is to propose one robust、stable control strategy for MAV to accommodate system uncertainties, variations, and external disturbances. In this paper, an interval type II fuzzy sliding-mode controller combined with PSO algorithm (ITIIFSMC-PSO) is proposed for MAV attitude control system. The proposed ITIIFSMC-PSO is a combination of the interval type II fuzzy logic control (ITIIFLC) and the sliding-mode control (SMC) which inherits the benefits of these two methods, furthermore, PSO algorithm was adopted to tune the type II fuzzy controller’s antecedent and consequent parameters for the plant control. The objective of the controller is to ensure the asymptotic stability of the closed-loop system. The Lyapunov stability method is adopted to verify the stability of the ITIIFSMC-PSO system. At last, a Quadrotor MAV with uncertainty and disturbance are adopted to illustrate the validity of the proposed method. The simulation results show that the ITIIFSMC-PSO achieves the best tracking performance in comparison with the interval type II Fuzzy logic controller (ITIIFLC), the interval type II fuzzy sliding-mode controller (ITIIFSMC).

The purpose of this study was to investigate the relationships of lifestyle factors, including energy intake and expenditure, to body mass index in male office workers. A total of 84 male office workers voluntarily participated in the study, and the participants’ lifestyle factors, which included body fat indicators such as body mass index, percent body fat, waist circumference, and waist-to-hip ratio, were measured. They also answered questionnaires recording their daily dietary intakes and average daily walking and sedentary time. For group analysis, the subjects were classified into normal weight (n=30) or overweight (n=54) groups based on a BMI cut-off point of 23.0kg/m2. Energy intake results showed that the overweight groups had significantly higher values for volume of dinner (p=.001), fat intake (p<.001), and frequency of skipping breakfast (p=.020) than the normal weight group. In terms of energy consumption, the overweight group had significantly lower values for commute time (p<.001) and significantly higher values for working hours (p=.017) and sedentary work time (p<.001) than the normal weight group. Pearson correlation analysis showed that dinner intake (p=.007) and sedentary work time (p<.041) were significantly related to BMI in both groups. Multiple linear regression analysis showed that dinner intake and sedentary work time were two independent predictors of BMI in office workers who participated in this study. In conclusion, the current findings of the study suggest that adopting healthy dietary habits, including dieting and regular meal times, as well as increased physical activity and reduced sitting time should be promoted as key components of lifestyle intervention for the prevention of body fatness in office workers.

As the skylight polarization navigation at present is based on dead reckoning which can only provide orientation information to navigate or relative position but not the absolute location of the observer, in this paper, a bionic absolute positioning method based on skylight polarization was proposed: the longitude and latitude of the current position could be solved through the polarization angle of the skylight, the course angle of the vehicle, the relative relationship between the solar and the earth. In addition, the simulation verification provided an accuracy of 0.483km in average. A positioning error model was developed, and the simulation shows that the precision of the sensors has a great impact on the positioning accuracy. Finally, the initial outdoor tests give a longitude accuracy of -0.149º in average and a latitude accuracy of 0.418º in average. Although the positioning accuracy obtained from the experiment is no better than the existing positioning systems, such as GPS, the proposed positioning method which is totally autonomous, convenient and without accumulated error is still worth to be improved since it would be useful when manmade positioning systems are disabled.

The relationship between the nuclear parameters and model performance is complex, which is from relevance vector machine (RVM) regression model based on Gaussian radial basis kernel function. Aiming at the problem of how to determine the kernel parameters of RVM, a method to selecting kernel parameter of RVM based on AIC criterion is proposed. Firstly, a novel of statistic Q is proposed based on “Akaike” Information Criterion (AIC), while the Q is as a fitness function. Secondly, we use the differential evolution algorithm (Differential Evolution Algorithm, DE) to find the best kernel parameter, in order to choose determine the kernel parameters. Finally, a RVM regression model mode is established and it is used in predicting gold price. Experimental results show that the prediction model has higher precision and better fitting the generalization ability than the traditional method, which demonstrates the AIC-based criteria for selecting RVM kernel parameter method is effective and feasible.

In the recent years, the demand for the grid connected inverters has increased immensely as they act as an interface between the photo voltaic systems and the utility. The focus of this research article is to model and analyze the design characteristics of a two level, pulse width modulated, grid connected inverter using Matlab. The Proportional Integral and Proportional Resonant controller are being investigated and the performance of these controllers is being discussed. These simulation results show that the proportional resonant controller is able to mitigate the harmonics and perform satisfactory as compared to Proportional integral controller under the same harmonic conditions.

In process-oriented software systems, many processes have large number of parallel redundant activities which are often used in split and merge workflow structures and make workflow model too complex to manage. Aiming at the homogeneity of redundant activities the structure characteristics of these homogeneous activities are analyzed and they are being classified into eight modes. Also the constraints is identified which defined the coexistence of these modes. At last a workflow model based on homogeneous activities is presented. Comparison shows that the method has obvious advantage in reducing description time and maintaining cost of workflow model.

In view of that part of motor fault state was difficult to be simulated by experiment; fault characteristic value was hard to be obtained quantitatively and so on. This paper established the finite element models of asynchronous motor in different fault conditions by Ansoft , extracted and analyzed stator current under different degree of motor broken bars, stator winding inter-turn short circuit and the air gap eccentric fault, obtained the fault characteristics with the evolution of fault degree. Finally established asynchronous motor fault experimental platform, through the comparison of the experimental data and the fault feature of the finite element models, validated the rationality of fault feature extraction method based on Ansoft.

In WSN (Wireless Sensor Network) every sensor node sensed the data and transmits it to the CH (Cluster head) or BS (Base Station). Sensors are randomly deployed in unreachable areas, where battery replacement or battery charge is not possible. For this reason, Energy conservation is the important design goal while developing a routing and distributed protocol to increase the lifetime of WSN. In this paper, an energy aware distributed protocol (EADP) for heterogeneous WSN has been reported. Proposed paper considers energy heterogeneous WSN to increase the lifetime of the network. An algorithm is proposed in the form of flow chart and based on various clustering equation proved that the proposed work accomplishes longer lifetime with improved QOS parameters. A WSN implemented and tested using Raspberry Pi devices as a base station, temperature sensors as a node and xively.com as a cloud. Users use data for decision purpose or business purposes from xively.com using internet.

The output characteristics of photovoltaic array was related with the topology of array, shadow distribution and illumination level. The theoretical analysis and simulation modeling of output characteristics of photovoltaic array including series array, parallel array and series-parallel array were made under the non-uniform illumination environment based on the circuit analysis. The photovoltaic cell was modeled by use of the improved two-diode model. Non uniform illumination is expanded from two illumination levels of traditional to N illumination levels and from the single series array to any number series-parallel array. The different analysis methods were adopted in different arrays for mathematical modeling and simulation. The current analysis was used in series arrays and voltage analysis used in parallel arrays. Analysis of current in branches and voltage between branches was used in series-parallel array. Then the mathematical models were established and programmed in m-file by MATLAB. The simulation models had a high computational accuracy, and were suitable for any simulation output characteristics of PV in different light environment and array topology. They could provide a theoretical basis for constructing the topological structure on the same condition and studying MPPT of PV array under non-uniform illumination.