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To understand the molecular mechanism of Pardosa laura in response to beta-cypermethrin (beta-CP) stress, next generation RNA-seq technique was employed to analyse the expression patterns of resistance- and stress-response genes in P. laura subjected to beta-CP. De novo sequence assembly yielded 49,003 unigenes, 20,912 of which were annotated in the public databases. A total of 370 up or down-regulated genes altered by beta-CP were detected, among them, 318 unigenes were upregulated, including one GST, one GPx, five CYP450s, two HSPs (one HSP70 and one HSP20) and two ABC transporters. Functional enrichment analysis revealed that carbon metabolism, glutathione metabolism, drug metabolism-CYP450, oxidative phosphorylation, as well as lysosome, phagosome and mTOR signaling pathway were predominately enriched in response to beta-CP stress. Certain critical genes involved in detoxification were detected to be differentially expressed between the beta-CP treated and control spiders. These results provide a fundamental resource for further research in the molecular characterisation of P. laura responding to pesticide.

In this work, some important factors such as ceramic shell strength, heat preservation temperature, standing time and withdrawal rate, which influence the formability of directionally solidified large-size blades of heavy-duty gas turbine with the liquid metal cooling (LMC) process, were studied through the method of microstructure analysis combining. The results show that the ceramic shell with medium strength (the high temperature flexural strength is 8 MPa, the flexural strength after thermal shock resistance is 12 MPa and the residual flexural strength is 20 MPa) can prevent the rupture and runout of the blade. The appropriate temperature (1,520 °C for upper region and 1,500 °C for lower region) of the heating furnace can eliminate the wide-angle grain boundary, the deviation of grain and the run-out caused by the shell crack. The holding time after pouring (3-5 min) can promote the growth of competitive grains and avoid a great deviation of columnar grains along the crystal orientation , resulting in a straight and uniform grain structure. In addition, to avoid the formation of wrinkles and to ensure a smooth blade surface, the withdrawal rate should be no greater than the growth rate of grain. It is also found that the dendritic space of the blade decreases with the rise of solidification rate, and increases with the enlarging distance between the solidification position and the chill plate.

Aiming at the operation safety of city gas polyethylene pipeline, this paper proposes a semi-quantitative risk evaluation technique to determine the possibility of risk failure and severity of consequence of PE gas pipeline. According to the basic procedure of semi-quantitative risk assessment, the failure probability and failure consequence of buried pipeline are analysed, and the safety risk level of each location of pipeline is evaluated comprehensively. The application of semi-quantitative risk assessment technology to gas polyethylene pipeline in a city in China shows that this technology can realize scientific management of pipeline according to risk level and further reduce the possibility of failure, so as to ensure safe, economical and reasonable operation of pipeline.

The applicability of wind speed measurement uncertainty evaluation with the pitot tube for the Guide to the expression of uncertainty in measurement (GUM) method is yet to be validated. Firstly, the uncertainty of the measured value of wind speed by the pitot tube is evaluated by GUM and Monte Carlo method (MCM). Then, the applicability of GUM method is verified by the method given in JCGM 101:2008 GUM supplement1, and it is concluded that the GUM method is still applicable to the evaluation of uncertainty in the wind speed measurement of pitot tube. Finally, comparing the GUM method with MCM, the influence degree of the GUM method on the volatility and dispersion of the probability distribution of wind speed measurement result is -0.31%~0.33% and -0.48%~0.26%, respectively. Since the degree of influence is small to the measured value of wind speed relatively, it is possible to determine whether to correct it according to the actual situation when applying.

This paper presents an approach of solfeggio audio machine assessment based on multiple audio spectrum features. In this machine assessment system, we analyze 13 spectrum audio features of solfeggio audios, and build a machine assessment model based on the scoring results of music experts, aiming to score the solfeggio audio system at the professional level based on machine learning techniques. An effective way is designed to implement the system with high generalization ability in this paper, with deploying 150 practice audio files marked with expert scores for training and testing the model. Various features are extracted to train predictors, which access the distances between practice audio files and their target audio files. In this way, these predictors can mark unknown audio files reliably. The training and testing process are described in detail, and the test results testify that our system can provide expert level scoring.

Leaf nitrogen content is an important index of crop growth and plays an important role in crop growth and development. In this paper, the hyperspectral data of winter wheat and the leaf nitrogen content is used to study winter wheat on flagging stage, flowering stage and grain filling stage. The estimation model of nitrogen content in winter wheat leaves at different growth stages is constructed by using partial least squares method and verified by using a cross-validation method. The results showed that R2 and the RMSE of the three growth stages were 0.53, 0.68, 0.64 and 0.331%, 0.246% and 0.406% respectively, and R2 and RMSE of model validation were 0.44, 0.71, 0.64 and 0.369%, 0.235% and 0.410%. Both the prediction model and the verification model had high reliability. Therefore, it is feasible for UAV to carry hyperspectral monitoring system for retrieving nitrogen content of winter wheat leaves.

Position disturbance is the most troublesome problem for load simulator. It is difficult to work properly for a loading system, when the load-carrying object is moving. Therefore, it is of high significance to compensate for the position disturbance. To achieve this objective, a kind of vector matching-based disturbance rejection (VMBDR) method is proposed. If the input is periodic and the load simulator system satisfies linear superposition, a torque command can be constructed to eliminate the position disturbance of the load-carrying object, according to VMBDR. Fortunately, linear superposition of electric load simulator is verified by experiments, and most of the position disturbance is cyclical. Compared with other methods, the VMBDR does not depend on building a precise mathematical model. Therefore, it has better maneuverability and adaptability. Finally, experimental results show that VMBDR has effective disturbance rejection performance.

The top word list, i.e., the top-M words with highest marginal probability in a given topic, is the standard topic representation in topic models. Most of recent automatical topic labeling algorithms and popular topic quality metrics are based on it. However, we find, empirically, words in this type of top word list are not always representative. The objective of this paper is to find more representative top word lists for topics. To achieve this, we rerank the words in a given topic by further considering marginal probability on words over every other topic. The reranking list of top-M words is used to be a novel topic representation for topic models. We investigate three reranking methodologies, using (1) standard deviation weight, (2) standard deviation weight with topic size and (3) Chi Square \c{hi}2statistic selection. Experimental results on real world collections indicate that our representations can extract more representative words for topics, agreeing with human judgements., Comment: The paper has been submitted to Pattern Recognition Letters and is being reviewed

Array acoustic logging plays an important role in formation evaluation. Its data is a non-linear and non-stationary signal and array acoustic logging signals have time-varying spectrum characteristics. Traditional filtering methods are inadequate. We introduce a Hilbert-Huang transform (HHT) which makes full preservation of the non-linear and non-stationary characteristics and has great advantages in the acoustic signal filtering. Using the empirical mode decomposition (EMD) method, the acoustic log waveforms can be decomposed into a finite and often small number of intrinsic mode functions (IMF). The results of applying HHT to real array acoustic logging signal filtering and de-noising are presented to illustrate the efficiency and power of this new method.

This paper describes a wheel hanging robot system that consists of a roller screw with a mounted 6 DOF manipulator and a visual workbench. It is designed to navigate autonomously and hangs wheels on the hook in the car wheel spray paint line. At the end of manipulator there is a holder used to catch and hang wheels. In order to achieve a better quality of spraying, a visual workbench can rotate the wheel to identify the rim’s circumference. Thus the valve hole can be identified and positioned with the mounted camera automatically. The whole control system of the wheel hanging robot system includes the manipulator control system, the mobile platform control system, and the rotating platform control system. Experimental results are shown that the wheel hanging robot system can position the valve hole of the wheels and hang wheels automatically.

Nowadays, Modern warship has been highly automated and integrated. Therefore, seemingly, the crew need copes with litter tasks than before. In fact, however, the crew's importance and tension have rapidly increased, even a slightest error may result in an accident. Consequently, consideration for human factor analyses should be taken independently in marine engineering. Our study focus is how to evaluate the ship power system control room design in the light of human factor analysis. According to the human factors theory, this article develops a common human reliability evaluation approach which is helpful to the ship general arrangement design for the highest efficiency of the whole ship. A case is also presented in this article, including the model test and HET analysis.

With a tunable cw semiconductor laser oscillating in a single longitudinal mode, measurement of an absolute strain is demonstrated with a frequency modulated interferometric method. Its measured resolution is 1.6 Hz/μe, range is more than 3.5×106 μe and just limited by the coherent length of the laser.

This research focuses on the design and debugging for a control system-Target Movement Simulation System. In order to acquire high performance of turntable in condition of time-variety load, ADRC (Active Disturbance Rejection Controller) is applied creatively in servo-control system. According to the variety of load and disturbance, the speed-controller is designed by ADRC. Then the experiment results indicate that the servo-control system using ADRC have better performance and better anti-disturbance capability than the general servo-control system. That is said, ADRC is effective method to achieve high performance of servo-control system with time-variety load.

To improve the positioning accuracy of CRTS II track slabs applied to the passenger dedicated line, a 6-DOF parallel mechanism is proposed as the positioning mechanism in the track slab fine adjustment system (TSFS), and the corresponding positioning algorithm is presented. After getting coordinates of prisms on slab measured by a total station, the base coordinate system of the parallel mechanism and the slab's body coordinate system can be identified by solving residual equations. According to the target location of a track slab, the parallel mechanism's target configuration is calculated and the slab can be positioned accurately by adjusting only once. Experiments show that positioning errors of track slabs are not more than 0.3 mm.

Aiming at the kinematics accuracy problem of the Stewart platform in the space docking hybrid simulation system, a cost effective calibration technique based on coordinate measurement is presented. The main idea is to acquire the position and orientation information of the platform by the coordinate measuring machine and construct a residual equation with uniform units. Then the platform's geometry parameters can be identified to compensate for its kinematics errors. The advantages of this method are that each geometry parameter's identifiability is ensured; no special auxiliary calibration equipments or redundant sensors are required to be designed and manufactured high adaptability and good operating characteristic are available. After the calibration procedure is described and the strategy on constructing the residual equation is discussed, a simulation shows that the kinematics accuracy after calibration can reach the same order of magnitude as measurement noises. Applying this method to an actual Stewart platform, the accuracy improves more than 5 times after compensation.

As an important means of obtaining spatial data, the unmanned aerial vehicle (UAV) remote sensing has such advantages as real-time, flexible, high-resolution, cost-effective etc, and it can gather information in dangerous environments without risk to flight crews. Because UAV remote sensing is a powerful supplement of spaceborne remote sensing and airborne remote sensing, it has enormous potential and bright prospect. In this paper, the compositions and key technologies of UAV remote sensing system are presented, and the applications such as land use, land supervision, flood disasters, meteorology disasters, geological disasters, forest fire disasters as well as surveying and mapping are summarized. In the end, we predict the main direction of studying on UAV remote sensing in the future.

Based on the measured tension curves of 16MnR and 20g steels, a three-point-bend specimen has been analyzed with elastic-plastic finite element method. The actual experimental conditions have been simulated to investigate the effect of pre-deformation ϵ p on the fracture toughness of 16MnR and 20g steels, the relations between the crack tip opening displacement δ t and COD-reduced factor β, and the effects of pre-deformation ϵ p on β C . The calculation results agree well with the related experimental results.

In this paper, various methods have been used to measure the effects of prestrain on the fracture toughness of 20 g steel experimentally. Based on elastic-plastic FEM analysis, the relationships between crack tip opening displacement δT and the maximum strain emaxc have been obtained and the effects of prestrain ep on the critical fracture strain emaxc have been examined. At the same time, based on the Rice-Tracey's void growth model [4], the cause of the void formation ahead of the crack tip, the condition of the principal crack propagation and the effects of prestrain ep on the fracture properties of 20 g steel were investigated. For ductile material there was a maximum value of V G ahead of the crack tip that was the cause of the void formation in that place. It is believed that when the maximum value of V G ahead of the crack tip reaches a critical value, it may be the principal crack propagating condition for high ductile material.

The fatigue process is studied by the method of damage mechanics. The equations for the evolution of fatigue damage of one and the same specimen with different irradiation parameters are given, all obtained by experiment. The results show that the study of fatigue damage of a specimen after irradiation by laser beam is of definite significance for the selection of the optimum irradiation parameters.

This article mainly discusses the model and software package for calculating ship reliability. Combining the fault tree analysis (FTA) method with multi-stage numerical simulation, the authors discussed the model and software package that can be used to calculate various parameters of ship reliability, such as mission reliability, operation readiness, etc. Further, the authors apply multi-stage numerical simulation into systems analysis and provide a new method to evaluate the reliability of repairable systems. An example of calculating the mission reliability of a submarine is given at the end.

This paper studies the effect of laser beam radiation on the fatigue crack growth threshold and the crack growth rate in 25CrMnSi steel plate. A comparison of radiated and unradiated specimens permits the derivation of an equation for the fatigue crack growth rate. The results show that radiation can enhance the fatigue threshold and retard crack growth rate.