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In order to forecast the malfunctional state of main power plant on ships through predicting the trend of unsteadily changed thermal performance parameters in main power plant system, this paper established AR model for thermal performance parameters using time series analysis method, by which to predict the change trend analysis of thermal performance parameters, and comparing the predicted values and the measured values. The actual application case of predicting a main engine’s exhaust temperature has been validated by using of the AR model, and results showed that: AR model can accurately predict the change trend of smoke temperature, and the prediction precision is higher, the average relative error was 0.25%.

Guide wheel crankshaft used in caterpillar tractor is analyzed under working condition. The crankshaft is made of 45Cr steel. Since the work conditions of the crankshaft are complicated, three dimensional finite element model of the crankshaft is built for strength checking of the crankshaft. Appropriate boundary condition is applied. The results show that the maximal stress of the crankshaft is 728MPa, which is less than the yield limit of 45Cr steel (835MPa). Therefore, the crankshaft can not be broken during the work of caterpillar tractor.

The polyanion of copolymer poly (2-methacryloyloxyethyl phosphorylcholine-co-methacrylic acid) (PMA30) was synthesized by free radical polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and methacrylic acid (MA). The synthesized PMA30 was assembled on chitosan (CS) surfaces formation of chitosan nanoparticles by polyionic complex. The chitosan nanoparticle was prepared using methacrylic acid (MA), 2-methacryloyloxyethyl phosphorylcholine (MPC) by template polymerization. The size distribution and structure properties of chitosan nanoparticles were characterized by scanning electron microscopy (SEM), dynamic light scattering (DLS), transmission electron microscopy (TEM) and zeta potential. These results show that a cell outer membrane mimetic surface was formed on the chitosan nanoparticles, which provides an effective way to improve the biocompatibility of chitosan nanoparticles.

The construction of the user model for achieving accurate personalized learning recommendation has an important role. The paper described the user model construction method based on ontology for multimedia video teaching resources in the field of agriculture. The concept and evolution of the ontology, user modeling technology and agriculture video ontology construction method is given, and the user model is realized and validated by experiment at last.

With the rapid development of wireless communication networks and mobile terminal technology, it has an important significance for improving the cultural quality of farmers and the rural information level that researching the key technology of personalized learning for farmers based on wireless network. The research progress of personalized service was introduced based on reading a large number of domestic and foreign related research literature. The personalized recommendation technology, the recommendation algorithm and measure method was given in the research of personalized technology. The personalized recommendation system was designed and tested, the result could need the users need. Finally the problems and future research directions in the personalized system is summarized.

The slope monitoring is the basis of slope management and ensure the safety of slope, is regarded year by year. This paper mainly introduced several kinds of more advanced, more commonly used slope monitoring method, elaborated the key from the principle and advantages and disadvantages, and analyzed the application of open-pit mine monitoring equipment from the Huogeqi mining area. It will have certain reference significance for selection of open-pit mine slope monitoring method.

In order to solve the decision information fusion issues of resource-constrained wireless sensor network, several decision information fusion rules under exponential distribution fading channel are investigated in this paper. At first, optimal likelihood ratio rule is given. The detection performance of this fusion rule is best, however, this rule acquires channel information which is too costly for resource constrained sensor networks. To solve this problem, suboptimal likelihood ratio fusion rule is proposed which requires only the knowledge of channel statistics. In addition, the reduced forms of the suboptimal are also derived, in the case of extreme channel signal-to-noise ratio (SNR). Theoretical analysis and simulations show that suboptimal fusion rule needs much less computation and information, yet exhibits only slight performance degradation. Suboptimal fusion rules are practicable for resource constrained wireless sensor networks decision information fusion system working in ocean environment.

This paper briefly describes the characteristics of two-dimensional code technology and realistic foundation, combined with the existing conditions and characteristics of distance education platform stream media system. Firstly, expounds the application value of two-dimensional code in the remote education platform, and then details and description of the application of two-dimensional code the Distance Education system architecture and system design and implementation of intelligent mobile phone client. From the analysis of application value to practical application of the two-dimensional code technology, state clearly that the application of two-dimensional code can further enhance the distance education platform service level, service ability, can provide better service for remote user education.

Rock breaking mechanism and coupling effect rule between cutter tool and surrounding rock were researched, in order to resolve the shield construction problem of shield cutter tool breaking rock. The optimal broken rock cutter spacing of some common rocks was put forward, and the broken rock mechanism of multi-tool is perfected. Considering the impact of various factors,this paper obtains a new calculation method of compound shield total thrust force and cutter-head torque with mathematical and mechanical methods. The research results can be used for design of thrust force and torque, tool selection and arrange.

In order to solve the problem which is very common when we use a solar water heater for a shower but the hot water can not come immediately because of the cooled water remained in the pipeline, a no-pump cycling water-saving equipment is designed based on a pressure-regulated suction device, temperature acquisition control circuit and a water-saving box. The kinematics and mechanics parameters are confirmed on the result of calculation and software simulation, and are tested by doing physical experiment. It can make it come true to economize the water and energy for solar power heater.

The past few years have witnessed increasing focus on the potential applications of wireless sensor networks. Sensors in these networks are expected to be remotely dispersed in large number and to operate autonomously and unattended. Clustering is a widely used technique that can enhance scalability and decrease energy consumption over sensor networks. We present an energy-efficient distributed multi-hop clustering approach for sensor networks, which combined multi-hop transmission with clustering method, aiming to balance the energy dissipation and prolong the whole network lifetime. Simulations showed that the protocol proposed worked nearly 100% more efficient compared with LEACH and HEED.