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Abstract:

Abstract: In order to give a more scientific "safety definition", the safety definition proposed by Mr. LIU Qian was supplemented and perfected under the guidance of safety scientology. And based on this, the new safety definition that "safety is an existence condition that rational person’’s body and mind are not harmed by external factors in a certain time and space (named after Liu-Wu’’s safety definition)" was proposed. Accordingly its denotation and connotation was analyzed. Meanwhile, definitions of other basic concepts in safety science were deduced by the rigorous logical tools. The results showed that the new safety definition can be used to reason and form the complete concepts group of safety science and these functions were much better than other existing safety definitions.

Abstract: In order to investigate the effect of water mist containing different additives on the alcohol extinguishing fire,exting experiments were carried out on water mist with different urea concentrations,potassium salt and FC-4 additives.The average fire extinguishing time of water mist with different concentrations of urea was compared under the same conditions.Comparing with water mist,water mist containing 1％ urea extinguished the alcohol fire in the shortest time,the extinguishing time reduction rate reached 44.63％.Water mist with K2C2O4· H2O extinguishied alcohol and kerosene fire in the minimal average extinguishing time,the extinguishing time reduction rate of fire suppression were 31.35％,73％ respectively.Water mist with KHCO3 extinguishied alcohol and kerosene fire in the maximal average extinguishing time,and reduction rates were 6.75％,57.56％ respectively.Water mist containing potassium extinguishing kerosene fire effect was better than to alcohol fire by contrast.Of all the compound additives,Water mist containing 0.05％ FC-4,1％ urea and K2C2O4· H2O with 0.2 mol/L K + extinguished the alcohol fire in the shortest time.And the extinguishing time reduction rate of fire suppression was 87.90％,the effect of fire suppression was remarkable.Compared with the above analysis,water mist containing compound additives was the better in alcohol extinguishing fire effect,and can realize extinguishing fire effectively.

Abstract: In order to tackle the stochastic time delay and state measurement obstacle in networked control systems, an observer-based mean square exponential stabilization controller was proposed in this paper. Firstly, the considered networked system was discretized by variable-period sampling and was modelled as a Markov jump system. Then, an observer and feedback controller was constructed. The mean square exponential stability of the closed loop system was shown. The observer and feedback gain was given by solving linear matrix inequalities. Simulation results demonstrate the effectiveness of the proposed method.

Abstract: Based on the characterisities of large-scale problems, lager-scale optimization were grossly analyzed. This paper  introduced some methods for lager-scale problems.The methods included the initialization method, decomposition strategy, updating strategy and so on. This paper mainly focued on the search strategy, update strategy, mutation strategy and cooperative coevolution. Meanwhile, the characteristics of lager-scale optimization algorithm testing function set and evaluation method were listed. Finally, the future research directions were given.

Abstract: For swarm intelligence algorithms, each individual in the swarm represented a solution in the search space, and it also could be seen as a data sample from the search space. Brain storm optimization (BSO) algorithm was a new and promising swarm intelligence algorithm, which simulated the human brainstorming process. Through the convergent operation and divergent operation, individuals in BSO were grouped and diverged in the search space/objective space. In this paper, the development history, and the state-of-the-art of the BSO algorithm were reviewed. Every individual in the BSO algorithm was not only a solution to the problem to be optimized, but also a data point to reveal the landscape of the problem. Based on the survey of brain storm optimization algorithms, more analyses could be conducted to understand the function of BSO algorithm and more variants of BSO algorithms could be proposed t22o solve different problems.

Abstract: The traditional anomaly detection algorithm for human beharior that based on image texture featurestended to describe the change of human image texture ranther than the actual situationof human motion behavior. Its detection porformance was not so good. In this paper, a method of feature extraxtion was proposed to reflect the real situation of human motion behavior. Firstly, the optical flow information was extracted by Lucas-Kanade optical flow algorithm, and the co-occurrence matrix and optical flow direction co-occurrence matrix were established. Then, the characteristics of two order distance,contrast, entropy and similarity are extraced by the co-occurrence matrix, and then combined them with the mean value of optical flow to form a feature vector to train the support vector machine(SVM).  Finally, this algorithm was used to determine whether the crowd had abnormal behavior. The simulation results showed that the feature extraction method in this paper had more in depth processing of the croed motion information provided by the optical flow method.Compared with the mainstream algorithm, it has a better recognition performance.

Abstract: The article aimed to fully explore the ability of bacterial algorithin and its varieties for solving the discrete optimization problems.The bacterial chemotaxis algorithm(BC), bacterial colony chemotaxis algorithm, bacterial evolutionary algorithm(BEA), bacterial swarming algorithm(BSA) and bacterial foraging optimization algorithm(BFO) are designed to solve the flexible job scheduling problem. Firstly, the model of the flexible job scheduling problem was formulated. Then the five algorithms were designed to solve the benchmark was instance. The results showed that the BFO outperformed the others Furthermove,a strategy to improve the BFO was proposed. More than ten optimization operators were designed and compared. Finally, the best structure of the improved BFO was built. The numerical experiments showed that the proposed BFO balanced the exploration and the exploitation very well and could solve FJSP effectively.

Abstract: A twice clutering metyhod(MAHC) was proposed based on meanshift and hirearchical. Firstly, in the CIE(LUV) color space, meanshift method is used for the first clustering to realize image smoothing and initial clustering. Then, the mean of each region was used as the initial value for the sceond clustering. And hierarchy clustering was used for the second clustering, which would be stopped until the clustering effect reached the expected effect. Finally, the mean of the aorta region was used as the seed point in the region growing, and  the imaga segmentation was finished. The MSHC method could improve the efficiency and effect of image segmentation, and the aortic arch model had a strong visualiuzing and realistic sense, which could cleariy show the three-dimensional structure.

Abstract: Latest research progresses of SLAM (simultaneous localization and mapping) using in the unstructured complex environment of lunar surface were summarized. In addition, we focued on summarizing and comparing the detection and matching of features of SIFT, SURF and ORB, and analyzed the three main methods: SLAM Based on Extended Kalman Filter, SLAM Based on Particle Filter and SLAM Based on Graph Optimization (EKF-SLAM, PF-SLAM and Graph-based SLAM). Furthermore, the challenge of SLAM technology was studied deeply. Finally, the future research directions of advanced SLAM were discussed. The research showed that certain research achievements were made in the study of s multi-sensor fusion SLAM, multi-robot cooperative SLAM, active SLAM and combined with artificial intelligence technology. However, there were few research in this field aiming at optimization method model, related problem branch research and semantic mapping which should be taken as the primary research direction in the next step．

Abstract: Multi-UAV cooperative mission planning was the key to multi-UAV cooperative combat. UAVs could share information with others and tackle tasks, which make it difficult to plan mission. In this paper, considering threat distribution, task sequence restriction and time of endurance, a mission planning mathematical model of multi-UAV cooperative mission planning was developed. To increase mission planning efficiency, limitations of traditional ABC algorithm were improved by introduction of dynamic evaluation selection strategy, introduction of metropolis rule , etc. The correctness and effectiveness of proposed method were validated by the calculation and analysis for multi-UAV cooperative missionplanning. 

Abstract: We investigate solar sail displaced orbits in the Hill’s restricted three-body problem was investigated, where the larger primary was an oblate spheroid in the system. Firstly, the model of solar sail equipped with a new version of reflectance control device was introduced. Next, dynamical model of the system with the larger primary an oblate spheroid was established and the Hill’s restricted three-body problem with oblateness was built through appropriate simplifications. The collinear equilibrium points of the Hill’s system varying with the variations of areas of absorption and thermal radiation of reflectance control devices in the solar sail, or the dimensionless characteristic acceleration of solar sail, or the oblateness of the larger primary are also investigated. Then, Linearization near the collinear equilibria of the system is applied. A linear quadratic regulator was used to stabilize the nonlinear system. The simulation reveals that solar sail displaced orbits in this system are doable and asymptotically stable by means of adjusting the pitch angle of solar sail and the area of absorption in reflectance control devices.

Abstract: To solve the problem that local mean decomposition (LMD) method was not insufficient in process the non stationary and non Gaussian signal, a fault diagnosis method based on the complementary ensemble local mean decomposition (CELMD) and spectrum analysis was proposed. Firstly, in this method,the white noises were added in pairs into a target signal, and then the noisy signal was decomposed into a series of production function by using LMD method.The PF component containing main fault information was selected, which was transformed by fast Fourier transform(FFT), to realize the identifications of the working status and fault types. Through the analysis of the simulation signals and the vibration signal of the bearing, it was proved that the method could eliminate the residual white noise and restrain the mode mixing, and improve the accuracy of the fault diagnosis as well.

Abstract: The load measuring system of the loader working device was constructed and the pin-shaft pretreatment load was used as the sample data. The sample length determination method based on central limit theorem was proposed, and the influence of sample length variation on the parameters of load mean amplitude distribution model was discussed. The results show that the proposed method could avoid the data saturation of the spectral density method and the dependence of the trend line fitting method on the model. When the confidence level was 0.95 and the statistical error was 0.05, the critical sample number was 48. The estimated parameters of the distribution model have obvious fluctuation when the number of samples was lower than the critical value. It tends to be stable when the sample number was higher than the critical value. This method had the advantages of high reliability, low test cost and small workload, which could provide an important reference for load measuring of the loader working device.

Abstract: To study on the performance consistence of the large-caliber telescope, the main 1m-caliber telescope was structure-designed and analyzed to achieve the comprehensive result. The materials of the main telescope were selected by comparing the materials’ nature, and light-weight design was proformed. After choosing the supporting scenarios of the main telescope and prepare case models. We proceed modal analysis to the main telescope parts, and verified supporting materials. Last, we conducted the gravity-transformative and thermal analysis on the main telescope. The weight of the main telescope was reduced to 76kg with a light-weight ratio of 77%. The simulation results indicated that: the RMS of axial and radial direction of the speculum were 8.9 nm and 3.5 nm respectively. After performing optimal design viai Sight, the radial self-weight deformation RMS of the primary mirror was improved to 3.3nm, decreased 5.7% comparingwith the RMS before optimization. When the temperature of main specular body reached 20± 0.3℃, the RMS was 10.1 nm, which satisfied the surface figure accuracy of the telescope.

Abstract: The unqualified parking brake installation and adjustment of passenger can easily lead to insufficient parking brake force or too small automatic adjustment gap of brake calipers, thus causing the problems of large wheel blocking force, brake dragging and so on. Taking a mini-car with manual parking mechanism as research object, the existing problems of the current parking brake installation and adjustment process of the car was analyzed, and a new installation and adjustment process was put forward and a set of automatic parking brake installation and adjustment system based on LabVIEM control was developed. The hardware design and control method of the system in detail was introduced and the test results proved that the new installation and adjustment process and automatic installation and adjustment system could improve the parking brake installation and adjustment consistency, reduce the labor intensity of workers, and have better application valinstallation and adjustment consistency, reduce the labor intensity of workers, and have better appication value. 

Abstract: In this paper, ABAQUS was used to simulate the response of carbon fiber composite laminates under low velocity impact. It was found that the increase od the impact energy, the maximum stress of each layer incread. By using the characteristic that the center wavelengths of FBG sensors to monitor the response of low velocity impact. By  analyzing the center wavelength captured by optic fiber grating demodulator, the relationship between the impact energy and the peak wavelength shift of sensors was found. Experimental results showed that, the embedded FBG sensors were able to accurately capture the transient impact signal and the peak wavelength shift of sensors could determine the size of the impact energy. With the increase of the impact energy, the peak wavelenght shift increase as well as the maximum stress of layer.

Abstract: According to the theory of heart transfer, a calculating method was presented for investigate the heat transfer and temperature distribution along the avial direction of large vertical reduction pot. The results showed that the well temperature of reduction pot decreased linearly with increase in altitude of the adiabatic section. In the heat transfer area, the wall temperature decreased in a nonlinear way with increase in altitude, the decreasing rate of which gradually declined, but the decreasing rate changeed abruptly in the place of the declining thickness. And teh method was further verified through comparative analyses of CFD and the field measured temperature. According to the reduction pot temperature distribution curve, the temperature of keypart of the pot could be collected. This could provide reference for practical engineering to solve the problem of the reduction pot material selection, reduction pot design, sealing material of pot connection selection. These results could have certain engineering application value.

Abstract: In recent years, drinking water pollution event have occurred, and it’s seriously harmful to social stability and security. It is very important to make a prompt and accurate emergency response to the pollution event and develop the optimal dispatching strategy when the pollution occurs so that provide the decision makers with suggestion.In this paper, the main object is how to optimize the hydrants and valves scheduling to bring the least assumption of pollutants and scheduling cost, the amount of pollutants absorbed, however, is contrary to the cost of scheduling. Therefore, this paper first develops a two-objective optimization model, and then uses NSGAII to solve the problem. The simulation results show the effectiveness of the proposed multi-objective optimization model and scheduling algorithm.
In this paper, this study mainly focued on how to operate hydrants and valves to reduce the impact and operation cost under sudden drinking pollution. However, the two goals of impact and operation cost were in conflict. Therefore, a two-objective optimization model was proposed, one goal was to minimize the consumed contaminated water, the other is to minimize the operation cost, and then a real water distribution system in a town of USA was employed and Pareto solutions were given by NSGA-II, at the same time, an comprehensive analysis of different factors was condcouted. The simulation results showed the effectiveness of the proposed multi-objecttive optimization model and scheduling algorithm.