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Hydrodynamic lubrication is an ideal state of lubrication in that friction and wear hardly occur. The friction pair of piston ring-cylinder liner is one of the most important friction pairs in a flowmeter. With the development of flowmeter aiming at high-precision and high-stability, how to make the piston ring-cylinder liner system maintain a good lubrication condition has great importance in terms of reducing the friction and wear. In this paper, a hydrodynamic lubrication mathematical model on the surface of piston ring was established. And the finite difference method(FDM) and successive over relaxation method(SOR) were adopted to solve the mathematical model numerically. The dimensionless average pressure of the lubrication film was taken as the criterion to estimate the hydrodynamic lubrication performance of the piston ring, and the effects of different flow rate conditions, different fluid viscosities and different minimum film thicknesses on the lubrication film pressure distribution were investigated respectively. The numerical analysis results reveal that: (a) the average pressure decreases with the increase of minimum film thickness, under the condition of the same minimum film thickness, when the medium is diesel, the average pressure is greater than the average pressure when the medium is gasoline; (b) the lubrication film pressure increases with the increase of flow rate, and the flow regime of the lubrication film changes with the change of flow rate; (c) as the viscosity increases, the pressure increases as well, for the same leakage clearance, the higher the viscosity, the larger load-carrying capacity of the clearance lubrication film. These results provide a guidance for lubrication design of piston ring-cylinder liner friction pair.

Due to the rapid development of electricity consumption and market, more and more related devices need to be used for the increasing users, the scale and structure of the secondary power distribution network have therefore become increasingly great and complex, lead to the result that line losses become higher line losses In order to better manage secondary power distribution network and reduce line losses, the paper proposed a new intelligent line losses management system for secondary power distribution network line losses. The system is built based on SSM framework and uses front-end and backend separation method. SSM framework is the integration of Spring, Spring MVC and Mybatis and thus has combined advantages of the three frameworks. The front-end is based on Bootstrap framework, and back-end is based on and SSM framework. In the system, data processing module, theoretical line losses calculation module and line losses evaluation module are built to calculate line losses and create the standards of line losses evaluation, while line losses management module is used for visualizing and monitoring the line losses situation which can be the reference of governance, planning and development of distribution network line losses problems. Finally, the system can help us make significant contribution to improving the benefits of power utilities, reducing energy waste, solving the environment pollution problem, and thus building an energy-saving and environmentally-friendly future.

Aiming at the delamination of bricks in powder compacting process, causes of delamination and force analysis on powder compaction are studied. Meanwhile, a mathematics model is established. Based on this model, a measure to reduce the delamination is proposed: increase the compressing velocity and pressure and decrease the raising velocity and height. The sequence of these influential factors is analyzed by orthogonal test. The correctness of the model is verified in the test and a best parameter combination has been put forward. The quality of production and production efficiency can be ensured in the powder compaction.

The conical silo and wedge-shaped hopper in the discharge system of ceramic press are important devices for storing and transferring ceramic powder. The conical silo stores ceramic powder and delivers the powder to the wedge-shaped hopper, which distributes the powder evenly in the grating. In order to provide sufficient supply quantity for brick pressing or improve the production efficiency of brick pressing, it is necessary to accurately predict the discharge rate of conical silo and wedge-shaped hopper. Based on dynamic arching theory and considering the influence of structure size, this paper deduces the prediction model of discharge rate of conical silo and wedge-shaped hopper, and proves the accuracy of the prediction model through discharge experiment.

The high speed blend machine is a new type of home appliance that can produce a variety of beverages. Its biggest feature is the high juice rate caused by the high speed of the motor, high nutrient retention and high absorption rate after breaking the wall. In the process of using the high speed blend machine, the design of different brands of high speed blend machine is not enough, and the skin residue of fruit and vegetable materials remains, which makes the crushing effect of the material unsatisfactory and affects the taste of drinking. Therefore, the research on the crushing performance of the high speed blend machine to improve the breaking rate of the fruit and vegetable materials has practical application value. We established a simplified model of the high speed blend machine by Solidworks software. We established control equation of the flow field based on the multiple reference system method, and then used the FLUENT software to simulate the flow field of the material. We analyzed the velocity distribution and the turbulent energy distribution of the flow field in the blend machine cavity, and summarized the motion law of the fluid in the cavity. The juice making performance was analyzed by changing the blade structure and the rotational speed. The feasibility of the numerical simulation results was verified, so as to provided basis for the improvement of the structure and control mode of household food processor.

This work presents a novel writing style-based approach to detect multi-account users on User-Generated Content (UGC) sites. Unlike existing works which emphasize feasibility and privacy leakage, we focus on precise writing style-based multi-account detection. Specifically, we leverage a one-class classification-based approach to detect multi-account behaviors, in which a mutual similarity measurement is defined to increase detection precision. In addition to traditional features used in writing style detection, we also extract bigrams, trigrams, part-of-speech, and grammatical relations. We evaluate our methodology based on datasets crawled from 3 popular OSNs (i.e., Twitter, Facebook, and Google+). Experimental results demonstrate that compared with the most recent achievements, our method not only improves the average detection precision to almost 90%, but also increases both recall and F-measure to 90% and even better.

The discrete time transfer matrix method for multi-rigid-body systems is improved based on the structural characteristics of the robotic arm and the relations between motion transfer and force transfer. A new multi-body system transfer matrix modelling method applicable to serial robots is proposed, and a unified model for a manipulator with n joints is developed. This model contains characteristics of both kinematics and dynamics. In view of the motion transformation relation of the robotic arm between joint space and the operational space, the solution and the procedure are proposed for forward kinematics of the system model. Numerical simulation of a 2R planar manipulator is performed. The simulation results validate the feasibility of the modelling method and illustrate it to be superior to the current methods.

Multifilter banks that have all properties of arbitrary order vanishing moment, optimum time-frequency resolution, symmetry and orthogonality together are constructed for the first time. Thus overcome the shortcoming of the present orthogonal optimum time-frequency resolution multifilter banks that have only 2-order vanishing moment. Due to the excellent properties, application experiments in image compression showed that, our multifilter banks outperform the best tools known as multiwavelet SA4, CL and Jiang's optimum time-frequency resolution J_EX2 in compressing with texture image.

Three kinds of Enhanced Boiling Microstructures(EBMS) were fabricated. A series of pool boiling experiments were carried out to estimate the performance of all kinds of EBMS. According to the results of pool boiling experiments, the best EBMS, which have the lowest wall superheat and highest Critical Heat Flux (CHF), was chosen as the most important part of a new designed Two-phase Closed Loop Thermosyphons(TCLT). The aim of the TCLT is to dissipate high heat flux of some electronic devices. The TCLT was composed of an evaporator, a condenser, a subcooler and connecting tubes. A series of dissipating heat experiments of the TCLT were carried out. Results show that thermal resistance of the TCLT can reach minimum value 0.077°C/W, and the highest heat flux that the TCLT can transfer is 44.2W/cm2 when pure water is the working fluid.

In the application of multiwavelet in image processing, the properties such as orthogonality, symmetry, vanishing moment, regularity, optimum time-frequency resolution (OPTFR) are very important. Through the algorithm we designed that synthetically used the method of parameterization, genetic algorithm and compound Simpson formula, we constructed multiwavelets which are better than the present ones in those properties. Application in image processing showed that the denoising performance of some of our multiwavelets are better than the best multiwavelets of Jiang’s J_EX2 and CL when dealing with smooth image and texture image.

Tacit knowledge is difficult for multinational companies (MNCs) to manage because of the high cost in cross-boder transfer. By introducing a model which is adapted from Nonaka 's knowledge creation spiral, this paper demonstrates the mechanics of tacit knowledge creating and integrating of MNCs'. A "ba" is defined as a real or virtual place for knowledge fermenting. Tacit knowledge can be created more often in the creating ba, and effectively integrated sequentially in the standardized fermenting ba, systematized fermenting ba, training and validating ba. According to the model, strategies, desire to share and learn, organizational synergy, culture, knowledge tools and other suggestions to manage tacit knowledge in MNCs are provided.