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This paper introduces a design of testing machine that could apply to the clamping tensile test for explosion-proof cable gland and a clamping tensile test for explosion-proof cable that based on this machine. The tension conduction system composed by wire rope and pulley supplies the test device for cable gland with tension by using standard weights counterweight. In order to ensure test precision, the testing machine loading platform can translate along the horizontal orthogonal direction X, Y and rotate around the X axis to adjust the sample space coordinates. The stress-strain sensor can measure the tension value, and the amount of displacement of the specimen can be measured by dial indicator. This paper focuses on the levelness-adjustable system and test methods.

Compared with the intrusion detection based on pattern matching, the method which is based on model checking can detect the complex attacks. But all of the existing algorithms are only used to detect some specific types of attacks. To solve this problem, we firstly use the Linear Temporal Logic with Past Construct (LTLPC) formulae to set up formal sub-models for the five kinds of attackers, the four kinds of attack processes and the eight kinds of attack effects. According to their universal relationship and the semantic relation of variety of LTLPC operators, we obtain the above sub-models together, thus, the universal models described by LTLPC formulae for universal attacks are formed. On this base, we implement an intrusion detection method based on LTLPC for detecting all types of attacks. Compared with the existing methods, the detecting ability of the new method is more comprehensive.

The NaCl-KCl-K2HfCl6 electrolyte successfully prepared by the reaction of HfCl4 with equimolar NaCl-KCl. Microstructure, surface morphology and components of the electrolyte were analyzed by XRD, SEM, and EDS. The results show that HfCl4 preferentially reacts with KCl when KCl and NaCl coexist or conversion relationship exist between Na2HfCl6 and K2HfCl6. The removal rates of oxygen reached 96.98%in electrorefining of hafnium attributed to high stability and low volatility of the electrolyte.

Compared with the intrusion detection based on pattern matching, the method which is based on model checking can detect the complex attacks. But all of the existing algorithms are used to detect some specific types of attacks. So, we firstly use the projection temporal logic (PTL) formulae to set up formal sub-models respectively for the five kinds of attackers, the four kinds of attack processes and the eight kinds of attack effects. According to their universal relationship and the semantic relation of variety of PTL logic operators, we obtain the above sub-models together, thus, the universal model described by PTL formula for universal attack is formed. On this base, we implement an intrusion detection method based on projection temporal logic for detecting all types of attacks. Compared with the existing methods, the detecting ability of the new method is more comprehensive.

Fiber ring resonator is widely used to generate stimulated Brillouin scattering(SBS). In this paper, the operation principle of SBS in a single mode fiber ring is analyzed, and the simulation method is proposed.

Large reservoir ecological risk assessment is an important part of ecological environmental protection and improvement. Taking Nuozhadu reservoir in Lancang river basin as an example, a multi-level risk receptor--multiple risk source evaluation index system which can describe the complicated relationship and mechanism of ecological risk is established in terms of recognizing ecological risk sources and receptors of the valley area of terrestrial ecosystems; Considering fuzziness of human cognition on ecological system, diversity and different measure standard of the risk evaluation indicators, the multi-level fuzzy comprehensive evaluation model based on RRM(Relative Risk Model) thought is constructed. Calculation results show that the ecological-risk fuzzy-evaluation score of each receptor and the overall score can be obtained, which can provide important reference for ecological environment improvement of Nuozhadu reservoir area through the comparative analysis.

A fiber ring is very commonly used to generate stimulated Brillouin scatterings(SBS), especially by using fiber ring resonator. In this paper we theoretically analyzed some parameters of our interest in a coupled fiber ring resonator. We firstly analyzed a directional coupler, determined the optical power distribution among the four ports of the coupler. Then theoretically analyzed the transmission function of a coupled fiber ring resonator, followed by the simulation of the analysis. The simulation results show that the smaller the coupling coefficient is, the better the cavity finesse and extinction ration are, the lower the SBS threshold is, which is of great importance when it comes to the generation of SBS.

Soil Mechanics, as one of the most important basic courses in civil engineering, hydraulic engineering and other courses, mainly analyzes the questions of deformation and stability of the soli body. The undergraduates begin to learn soil mechanics after finishing advanced mathematics, college physics, theoretical mechanics and mechanics of materials. The objects researched in the above-mentioned courses are idealised, so the rigorous mathematic deduction is feasible and only a few hypotheses are needed. Soil is different from other materials, so inevitably the methodology and thinking mode in soil mechanics are special compared with other mechanical courses, which makes students feel confused at the beginning stage of this course. It is necessary to let students know the teaching idea, research method, common problems during the instruction of soil mechanics, which is also helpful to their further studies and researches. Based on these factors, an inductive teaching method is put forward, which summarizes the essential ideas and important questions in soil mechanics.

Economy and hydraulic stability of piping network which has a fixed structure depend on the matching ability of pipe diameter. In order to improving the matching ability and maneuverability of selecting pipe diameter, a new design method is presented. A real case study shows that the piping network which is designed with the new method has excellent technical quality and the least life cycle costs, and can achieve saving more than 7 percent against the original design.

The operation of the Three Gorges power station is of the most complex feature in China and even in the world, for it involves many factors such as flood control, power generation, shipping and water supply. This paper takes the experimental reservoir impoundment in 2008 for example, demonstrated its impact on power grid operation, meanwhile, put forward suggestions on impoundment time, impoundment target, impoundment and fluctuating process and adjusting mechanism building, etc.

Dynamic modeling method for parallel indexing cam mechanism was presented based on rigid-flexible coupled modeling according to the analysis of mechanism feature. Dynamic simulation has been done with the dynamic model established by means of Adams. Dynamic characteristics of different transmission functions commonly used in practical engineering were analyzed in detail from the perspective combined kinematics and dynamics. The application principle of transmission functions was presented based on dynamic simulation and analysis results. That is Modified Cosine transmission function being suitable for applying in low speed or low precision transmission cases, Complex or Gutman’s transmission function being suitable for applying in high speed, heavy load or precision transmission cases. Complex transmission is the best one for design of high-speed indexing cam mechanism.