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Advantage of solid adsorption refrigeration is environmental protection, energy saving, simple structure, no noise and the advantages of stable and reliable operation, the use of solar energy driven refrigeration is an energy-saving environmental protection technology, it can effectively reduce the huge energy consumption and environmental pollution due to the burning of fossil energy resources. This article introduces the general situation of development of solar adsorption refrigeration, puts forward the research progress and application prospect of the solar energy air conditioning system.

In this work, six asymmetric compound parabolic concentrators (ACPC) were designed for concentrating radiation on all-glass evacuated solar tubes (EST). The ACPCs are required to be horizontally oriented in the east-west direction and to collect direct sunlight for at least 6 hrs in any day of a year. The angular dependence of optical efficiency of six ACPCs, identical in the height of both reflectors after the higher reflector being truncated, was investigated by ray-tracing method, and the annual radiation on EST concentrated by ACPCs was estimated based on solar geometry and monthly horizontally radiation. Results shows that the ACPC designed based on “hat shaped” virtual absorber with a V-groove at the bottom of reflectors is the best in terms of the optical efficiency averaged over the acceptance angle, followed by the one designed based on “hat-shaped” absorber without a V-groove at the bottom, and the one designed based on the cover tube of EST is the worst. However, from the point of annual radiation on EST, the ACPC designed based on the cover tube is the best solution, followed by the one designed based on “ice-cream shaped” absorber and the one designed based on “hat shaped” absorber is the worst due to the smallest geometric concentration factor.

A variety of different magnetic structure models of cobalt doped zinc oxide have been calculated by density functional theory (DFT) of first-principle method. Crystal structure parameters and the total energy of the models are obtained through the computational simulation. Through contrasting and analyzing the total energy of each of the structure models, it is found that the cobalt doped zinc oxide crystal material with anti-ferromagnetic state is more stable than the one with ferromagnetic state. The electronic structure of the models with anti-ferromagnetic is investigated and the results show that the cobalt 3d electrons have a great impact on the characteristics of the electronic structure of the zinc oxide.

The absorption thermal energy storage (TES) system stores the energy in the form of potential energy of solution and is a promising technology for efficient energy transformation process. The performance of the absorption refrigeration system with integral storage for cooling applications using LiBr-H2O as working pair under the condition without crystallization was analyzed on the basis of the first law of thermodynamics. Simulation was employed to determine the coefficient of performance (COP) and energy storage density (ESD) of the absorption TES system under different conditions such as the absorption temperature and storage temperature. The results show that the COP of the system is 0.7453 and ESD is 169.853 MJ/m3 under typical operation conditions in summer. A low absorption temperature yields both a higher COP and ESD. The solution heat exchanger could improve the COP of the system while has no effect on ESD. Results also showed that system has a good advantage when compared to other storage methods since it is do no need thermal insulation. The absorption TES may be considered as one of the promising thermal energy storage methods.

A two degree of freedom large-stroke linear FTS device was designed in this paper, the device with flexible hinges as the guidance and support part, achieved the linear degrees of freedom in X and Z. In addition, structure design and optimizationanalysis of static characteristic and dynamic characteristicresponse surface analysis of FTS device were worked as well in this paper ,then the stiffness and strength characteristics of FTS device has been greatly improved, fully meet the design requirements, achieved the desired effect.

The dynamics of flocculation is always one of the most interesting and difficult points for water treatment. The applicability of existing breakage rate coefficients was restricted due to the limitations of their theoretical derivation. In order to solve this problem, a breakage rate coefficient of flocculation process was derived based on shear strength. It could be described by the equation "s(m)=E0Fr1.2m1/D". Then it was applied to a flocculation model which described the change of particle size distribution during flocculation. Laboratory scale experiments were carried out to verify the feasibility of the new breakage rate coefficient with the typical surface water in northwest China characterized by low temperature and low turbidity. Results indicated that both the change of particle size distribution with time and the effects of operation variables on the stable particle size distribution could be excellently simulated, agreeing well with the experimental results with the relative error ranged from 3% ~ 17%. It was demonstrated that the breakage rate coefficient based on shear strength could be used to describe the breakage rate of flocs during flocculation.

Damage testing of components is a key point in many industry fields. In some cases, endoscope is used to inspect the damage part, while the images are often noised. In this paper, we focus on industrial image denoising based on multiwavelet Riesz bases. Starting from compactly supported vector refinement equation, we provide a characterization to form two Riesz bases and an example is given. Based on example Riesz bases, we research industrial endoscope image denoising and get satisfying result.

The rapid development of China’s economics makes it urgent to widen the existing highways especially those located in the south-eastern coastal areas over thick soft soils. Adding a new embankment adjacent to the existing highway embankment is a cost effective choice compared with the traditional methods to build another new one and can reduce the heavy traffic pressure. However, it may also cause some engineering problems including the excessive settlements settlements, road cracks, excessive tensile stresses on the pavement even local or global instability of embankments. So some proper measures should be taken to solve the problems caused by widening is of great importance in engineering practice. A numerical analysis was performed to investigate the effect of different kinds of soft soil treatments including rigid piles, stone columns and prefabricated vertical drains (PVDs) usually used in highway widening projects located in the thick soft soils. It was found that the rigid piles can effectively reduce the additional settlements of the existing embankment induced by widening as well as the settlements of the widened embankment. While the stone columns and PVDs play little role in controlling the additional settlements caused by widening.

Two kinds of surface heat treatment (wide-band laser surface quenching and high-frequency induction quenching) had been performed on a ferrous PM cam material for automobile applications. Microstructure, hardness and tribological properties of ferrous PM cam materials were investigated. After laser surface quenching, the sintered cam materials could obtain finer martensite microstructure and higher hardness value, compared to high-frequency induction quenching. Wear tests revealed the superior wear resistance and coefficient of friction of laser surface hardened specimens in comparison with high-frequency induction quenched ones. Laser surface quenching can be a more effective surface heat treatment to improve wear resistance of the sintered cam materials than high-frequency induction quenching. On the lower test loads (such as 50N), the wear mechanism of the surface quenched ferrous PM cam materials is dominated adhesive and abrasive wear, while on the higher test loads (such as 120N and 150N), it is primarily delamination wear and abrasive wear.

Slow light properties of the photonic crystal line-defect waveguide are researched with the plane wave expansion method. The structure of the waveguide is adjusted with several methods mentioned above at the same time and the slow light properties get better. For the structure of dielectric rods, central frequency and the group velocity of the guided modes decrease with the increase of the radii of the defected rods as well as the dielectric constant. Effects on the slow light from the change of the defected rods’ position are also studied, through moving the rods up and down; we get the almost linear guide mode which has flat slow light curve and smaller group velocity. In a word, group velocity of the slow light is mainly affected by the radii and dielectric constant of the defected rods, and group velocity dispersion is decided by the change of the defected rods’ location.

Piled embankments are increasingly used to construct highways on soft soils. End-bearing piles for supporting embankment exhibit different characteristics for the soil arch developed within the embankments. A numerical analysis was conducted to evaluate the soil stress concentration ratio, pile and soil settlements, pile axial force, negative skin friction (NSF) and location of the neutral plane (NP) during embankment filling and consolidation of soft soils. The results indicate that the stress concentration ratio varies with time and most of the embankment load is born by the pile. The soil pressure on the soft soils increase and reach a maximum value during the filling, then decrease gradually and maintain nearly a constant value at the end of the consolidation. The settlement of shallow soft soils differs significantly from that of the deep soft soils. The location of the NP shows a complicated variation.

Aimed at characteristics of mass moment of missiles in exo-atmosphere, it’s inferred that 6-DOF mathematical model based on mass moment controlling stabilities on three axes. Considering the problem of harmoniously controlling two moving masses, moving mass based non-linear theorem was used to solve a series of problems met in attitude control system design. In order to weaken the chattering of the system, a saturation function is introduced to substitute for Sign function to improve the variable structure control law so that the chattering can be depressed. The simulation results illustrate the efficiency of this method.