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The research is to analyse the immunohistochemical reaction of orthodontic force on the periodontium reformed by nanobiphasic calcium phosphate ceramics (nBCP). Two third incisors were selected randomly and operated as experimental groups in 2 Beagle dogs. In the labial aspects of the third incisors, alveolar bone defects were surgically made and implanted with NBCP. The contralateral teeth in the same jaw did not receive any treatment as control. After 24 weeks, all the third incisors were moved labially. The dogs were euthanized 4 weeks later. The expression levels of osteocalcin were detected by immunohistochemical staining. Positive osteocalcin expressions in regenerated periodontium were observed and compared with the normal periodontium in the control groups. There were no significant differences within and between them. It means the periodontium regenerated by nBCP can bear orthodontic forces with a normal function. Based on these findings, we concluded that nBCP may offer a new bone graft choice for periodontic disease patients who have demands for orthodontic treatment.

A novel palmprint recognition method based on sparse two-dimensional local discriminant projections (S2DLDP) is proposed. After a description of the basic theory and resolution method for S2DLDP, the paper presents the detail palmprint feature extraction method based on S2DLDP, and tests the algorithm performance by various non-zero elements size and neighborhood size. S2DLDP considerers the class information, local separability, two-dimensional image inherent properties of training samples and sparse projection, which provides an intuitive, semantic and interpretable feature subspace for palmprint representation. The optimal recognition accuracy of EER=2.2% is obtained on PolyU palmprint database, which also illuminates the effectiveness of the proposed algorithm.

Construction machinery hydraulic cylinder is usually discarded after service cycle. The residual value of discarded products can be recycled greatly by remanufacturing. Disassembly and assembly is the key process in hydraulic cylinder remanufacturing. The construction machinery hydraulic cylinder disassembly and assembly equipment is developed. Hydraulic power is adopted in this equipment. The clamping, positioning of cylinder tube is realized by hydraulic clamping mechanism automatically. The piston component pulling out or into cylinder tube is realized by hydraulic working mechanism automatically. This equipment has been applied successfully in the project of "key technology and equipment for construction machinery parts remanufacturing" in a research institute. The results indicate that the application of this equipment will not only increase the automaticity and efficiency remarkably, but also reduce the damage to hydraulic cylinder key part greatly.

The effect of MgO on phase composition, alumina leaching properties and the self-disintegrating rate of calcium aluminate slag were investigated by X-ray diffraction and another analysis method. And a feasible method is proposed to eliminate the negative effects of MgO. The results shows that: the phase of 2CaO·SiO2(C2S)、20CaO·13Al2O3·3MgO·3SiO2(Q phase) and 12CaO·7Al2O3(C12A7) are formed when there is MgO in slag with the C/A=1.4 and A/S=1.3. The content of Q phase increase and the leaching rate of slag reduce with increasing the temperature and the content of MgO. MgO would reduce self-disintegrating rate of slag. CaSO4·2H2O can improve the self-disintegrating the leaching properties of slag by promoting the synthesis of C12A7 and inhibit the synthesis of Q phase.

Traditional textile dyeing industry, which is always based on open-loop control strategy, has the problem of high energy consumption and serious pollution because it is difficult to deal with the direct control problem of the dyeing process. Based on the multi-variable dyeing uptake rate integration model, this paper proposed a closed loop control system using Generalized Prediction Variable Structure Control (GPVSC) algorithm. The integrated model is used as the soft measurement method of the whole closed loop control system, which can solve the problem that it is hard to measure dyeing uptake rate directly during the batch dyeing process. In the aspect of control algorithm, the Generalized Prediction Controller (GPC) was combined with Variable Structure Control (VSC), where the temperature was selected as the control variable, which achieved the control of the dyeing uptake rate during the batch dyeing process. Simulation results show that the algorithm could exactly track and control the dyeing uptake rate during the batch dyeing process.

Purpose: studied the mechanism of polycarboxylicacid plasticizing effect on α-calcium sulfate hemihydrate. Methods: the adsorbed amount was tested by ultraviolet visible absorption spectrum method, ζ potential was measured by micro-electrophoresis analysis, and the corresponding workability was studied. Results: firstly, polycarboxylicacid plasticizer was adsorbed on α-calcium sulfate hemihydrate by Van Der Waals force and the saturated adsorption quantity of polycarboxylicacid plasticizer (HC) was about 5.8mg/g; secondly, the decisive factor for polycarboxylicacid plasticizer to disperse α-calcium sulfate hemihydrate particles was the steric hindrance of polycarboxylicacid plasticizer, and the maximum ζ potential of α-calcium sulfate hemihydrate with polycarboxylicacid plasticizer was-9.360mv, much less than β-calcium sulfate hemihydrate under the same conditions; finally, the perfect mixing content of polycarboxylicacid plasticizer was 0.3%~0.6%; it increased fluidity by 66%, to the maximum 300mm.

Dyeing textile’s information management system is the basis of accurate classification of color， machine studying methods have became a popular area of research for application in color classification. Traditional classification methods have high efficiency and are very simple ， but they are dependent on the distribution of sample spaces. If the sample data properties are not independent， forecast precision will been affected badly and internal instability will appear. An application of Gray-Relation for dyeing textile color classification has been designed， which offsets the discount in mathematical statistics method for system analysis. It is applicable regardless of variant in sample size， while quantizing structure is in agreement with qualitative analysis. On the basis of theoretical analysis， Dyeing textile color classification was conducted in the conditions of random sampling、 uniform sampling and stratified sampling. The experimental results proofs that by using Gray-Relation， dyeing textile color classification does not need to be dependent on sample space distribution， and increases the stability of classification.

The charge plan is a basic problem of the metallurgical industry. Through a comprehensive consideration of the process constraints and production costs, charge plan is a typical multi-objective optimization problem. A multi-objective optimization model of charge plan was built in this paper. As direct encoding is hard to be used in the many constraints problem case, a new method of generate feasible solutions based on constraint satisfaction was proposed. A novel adaptive grid algorithm was also proposed to improve the current multi-objective evolutionary algorithm’s population maintain strategy. Finally, the proposed multi-objective charge plan model was solved, and more meaningful solutions for this problem were obtained.

Using calcium alginate medical film to explore the preventive measures of bone cement leakage in PVP.60 fresh vertebral bones were dissected from pigs(10 months old with average weight 152.5±7.5kg), and randomly divided into the blank group, the control group and the experimental group, 20 vertebral bones for a group. Eliminated the extra muscles and ligaments and the upper and lower endplates were completely retained. The models of vertebral compression fractures with fissures in front of vertebra were prepared by drilling two holes with a 3.2mm electric drill from lateral of the junction of the halfway point of parapophysis and the vertical of superior articular process to anterior vertebra along the direction of pedicles of vertebral archs by angle 10 and 15 degree and downward sloping 5 degree with the sagittal planes. Only bone cement was injected to the blank group, while the control group were injected with bone cement after injected medical fibrin glue. And the experimental group were injected with bone cement after injected sodium alginate glue and solidified by saturated calcium chloride. The injection dose of bone cement was recorded when bone cement leaked. The injection dose of bone cement in experimental group was significantly higher than the blank group and the control group when bone cement leaked (P

Modifying crystal morphology was the key technology of the preparation of α-calcium sulfate hemihydrate from flue gas desulphurization gypsum using the hydrothermal method under atmospheric pressure. For exploring crystal modifier, the crystal morphology of α-calcium sulfate hemihydrate in preparation from flue gas desulphurization gypsum with various organic diacid was studied, by polarizing microscope profile observation. The results showed, When the space between two carboxyls was triplicate length of C-C, the organic diacid had the best effect of modifying crystal morphology.

The tensile and low cycle fatigue tests were carried out on alumina short fibers reinforced Al-Si piston alloy composites (Al-Si MMCs). Three Al-Si MMCs reinforced with 10, 17 and 25 vol.% of alumina short fibers were prepared to investigate the effects of volume fraction on tensile and low cycle fatigue properties at room temperature (RT) and 350°C. The results showed that the tensile strength decreased with the increasing of volume fraction of fibers at RT and was slight different at 350°C. Among the three MMCs, the 17%-MMCs showed highest stress level under the low cycle fatigue tests. The fatigue cracks were usually initiated from the clustered and large size fibers near the surface of specimen, propagated along the fiber/matrix interface at RT and grew rapidly by means of broken the fibers at 350°C.

In this paper, TiN coating as an interlayer was fabricated on Ti substrate by reactive plasma spray. Ti/TiN/Sb-SnO2 electrodes were prepared by SOL-GEL method and the influence of the TiN interlayer on the structure, oxygen evolution potential and service life of the electrodes was studied. It was shown that the surface of the Ti/TiN/Sb-SnO2 electrodes is more homogeneous and the oxygen evolution potential and accelerated life are both higher than those of the Ti/Sb-SnO2 electrodes.

A new structure of a-Si/ poly-Si tandem solar cell has been desiged and prepared. Amorphous silicon has been use as photovoltaic material of bottom cell. And polysilicon has been used as photovoltaic material of bottom cell.The combination of amorphous silicon and polysilicon extends the light range which can be used by solar cell. This structure improves the efficiency of solar cell greatly.

Metal-oxide-semiconductor (MOS) structure is highly sensitive to SiO2-Si interface. It will reflect parameters such as interface density and oxide layer charge expediently. For the sake of researching of radiation effect of MOS structure irradiated by electron, we adopted 0.8 MeV electron at dosage between 2×1013cm-2~1×1014cm-2as radiation source respectively. We found that electron radiation will induce interface density at SiO2-Si interface. According to comparison with C-V curve of MOS structure at high frequency and low frequency, we obtain that the experimental data of interface density is up to 1014(cm-2eV-1). In addition, we also obtain the relationship between the parameter and radiation dosage.

Based on the ABAQUS software, set up the tunnel and adjacent buildings and their pile of calculation models, analysis shield construction on the deformation of adjacent buildings and pile foundation. Analysis shows that the construction of the tunnel shield leading to surface subsidence, causing deformation of the framework structure and underground pile. Also shows Shield construction on the impact of adjacent buildings and underground pile deformation is integrally related.

The paper make the service life of relieving formed milling cutter as the optimization objective, proceed the simulation study on the mechanical degree of cutter, cutting data. The concrete method is that the orthogonal milling model is established to simulate the simulation milling process, some basic parameters which are obtained in the machining process are analyzed and discussed. The results indicate that the finite element simulation of the metal cutting processing can analyze quantitatively some physical properties, such as the cutting force, stress, strain and so on, the traditional way of qualitative analysis is changed. The state of machining is in favour of grasping in the theory, the theory and technology are provided to establish the proper processing technology strategy.

×MOS structure has been radiated by electron, dosage is 2×1013 cm-2 ~ 1×1014 cm-2. The interface density distributing in energy band has been tested by quasi-static method. It is found that interface density increase while electron dosage increasing. When dosage arrived to 1×1014 cm-2, interface density arrives to 1013(cm-2eV-1),which is two order of magnitude higher than without irradiation. Further more, the shapes of density increase curve are completely different.

The effects of Cu element on properties of Al-Mg-Si aluminum alloy was studied, and the mechanism of Cu in influencing the property of the alloy was discussed. The results indicate that Cu element can weaken the conductivity property of alloy material, its thermal conductivity is improved with slow cooling. Cu element is sensitive to corrosive property of the alloy, it can cause corrosion resistance decreasing significantly, quenching heat treatment made corrosive property of the material deteriorative. Proper Cu element is helpful to microstructure refinement and the enhancement of strength, tensile strength of the material is increased 10 percent after solution treatment and ageing strengthening.

The aim of the present study was to assess the effect of nano-biphasic calcium phosphate (nanoBCP) scaffolds on acute alveolar bone defects in beagle dogs by micro-computed tomographic imaging (μCT). Alveolar bone defects were surgically created bilaterally at the buccal aspects of the upper second premolars in four beagle dogs. After root conditioning with ethylenediaminetetraacetate (EDTA), nanoBCP was randomly filled in the defects and nothing was put into the contralateral defects as controls. Dogs were killed at the 24th weeks. Specimens were scanned and reconstructed though μCT. The results revealed that much new alveolar bone formed in the defects in the nanoBCP groups while no new alveolar bone formed in the controls. The present results indicate that PBCP may enhance alveolar bone regeneration in acute-type labial dehiscence defects.

Based on the monitoring data of the deep foundation pit, established an adjacent deep foundation pit safety risk fuzzy synthetic evaluation model, and then determine safety grades , using the method to evaluate the safety of the environment surrounding the foundation pit. Practice proves that the method can reflect the risk condition of the pit, and provided a new way to check the security of the pit.

In order to dominate the lighting market, LED needs more electrical power to be driven for higher brightness, thereby increasing thermal power dissipation, which contributes to a high heat flux of 85W/cm2 within a recent typical high power LED chip. And the junction temperature has direct influence upon the light output efficiency, device life time, emitting wavelength and reliability of LED. Therefore, effective removal of heat to maintain a safe junction temperature is the key to meet the future flux per LED requirements. Compared with other individual thermal resistances along the thermal path, thermal design for much lower packaging thermal resistance is more critical to improve the performances of LED. In this paper, major present technical researches on packaging thermal management were analyzed for high power LED, and the advantages and shortcomings of these techniques were respectively summarized. Besides, some suggestions were provided for further research in this area.

In order to discuss the friction resistance properties between pile and soil, three groups of shear laboratory tests of pile-soil interface are adopted among concrete-soil , steel-soil and plastic(HDPE)-soil, and each test applies six normal stresses. The result indicates that with the growth of normal stress, the shear strength of pile-soil are increased; under the same normal stress, there is little change in frontal parts of curve with shear stress and displacement, but the rest of curve have a striking change along with the increase of normal stress; when the normal stress is less, the shear stress of different interfaces have little change; when the normal stress is greater, it shows that the shear strength of HDPE-soil interface is the greatest.

In the paper, a model is developed to discribe the band gap energy of Ⅲ nitride alloys. A new parameter A is used to discribe the band gap bowing. The new bowing parameter A is obtained by fitting the experimental values of the band gap energy. AAlGaN =0.46, AInGaN =0.59 and AInAlN =1.90 are obtained by fitting the experimental values of the band gap energy for AlGaN, InGaN and InAlN, respectively. The model is also suitable to discribe the band gap energy of other Ⅲ-Ⅴ ternary alloys.

The paper reports the setting up of a model of fluid dynamic for GaN HVPE system and the simulation. The deposition of GaN with the variation of the gas flow inlet velocities is investigated. The influence of diffusion coefficient on the deposition of GaN is also discussed. It is found that the influence of the gas flow inlet velocities on the deposition is large and the influence of diffusion coefficient on the deposition of GaN is small in vertical HVPE.

In the paper, the factors influencing the band gap bowing of the bulk alloy with random distribution are analyzed and it is found that the bowing coefficient is compositional dependent. The reasons for the large dispersion of the bowing coefficient are also analyzed. In addition, we obtained the bowing coefficient (b=2.26+5.04x) for InAlN by fitting the experimental data.

The spreading resistance is a very important parameter in the applications of heat sink. The design of electronic devices will fail without considering the influence of the spreading resistance. In this paper, a simple thermal model was simulated by Computational Fluid Dynamics software. Some factors, which have great influence on the spreading resistance, have been analyzed. The spreading resistance decreases significantly with the increasing of the area ratio between the heat source and the base-plate. While the ratio being 1, the spreading resistance reaches the mix value. The greater the thermal conductivity of heat sink, the lower the spreading resistance. With the increasing of the thickness of base-plate, the spreading resistance reduces. However, if the thickness exceeds the critical value, the spreading resistance will increase. And the spreading resistance reaches the mix value while the centers of heat source and the base-plate are overlapped.

Prestressed concrete double Tee floor slabs are widely used for the roof of building construction. Some problems are met during the development practice of this type of precast structures. Firstly, the overhang flange of the traditional double Tee floor slab is not enough large in the view of economic and utilization. Secondly, it is not easy to dispose the skylights on the roof used double Tee floor slabs in the workshops or the gymnasiums. Thirdly, most of the beams are produced in prestressing plants, but very few productions are made in site. Therefore, a new type of prestressed concrete double Tee floor slabs have been designed with some characters such as 3.0-m outside flange, flange slabs with rectangular opening holes for the skylights or not, and the beams produced in the prestressing plants with pre-tensioning prestressing tendons or post-tensioning with the strands in site.

In this paper how to utilize industrial wastes in soil stabilizer preparation with high added value is discussed. Firstly the characteristics of stabilized soil structure formation process and its special demand of stabilizer components were explored. Based on this, the design thought for the soil stabilizer prepared with industrial wastes is proposed and the examples are presented. Then technical, economical and environmental comprehensive index is analysed. Only if stabilized soil structure formation process was understood deeply and industrial waste was chosen properly according to the special demand of stabilized soil structure to components, the change from waste to resource can be realized. And then the stabilizer can be prepared with excellent performance, cost, environment effect and comprehensive benefit.

The method to improving surface corrosion resistance of 6063 aluminum alloy was studied, and the mechanism of surface corrosion resistanc was discussed in theory. The results indicate that the adjustment of chemical composition is of advantage to corrosion resistance of the alloy, its property is better as Mg, Si mass ratio at about 1.55. The necessary homogenizing treatment of cast ingot subserves corrosion resistanc of aluminum extrusion, and the cast ingot should be cooled quickly after heat treatment. Significant effect of extrusion technology on erosive property is observed from aluminum alloy, aluminum extrusion has good corrosion resistance when outlet temperature is at about 510 degree centigrade.

The FEM mehods for simulating the penetration of jacked pile were summarized. Using the displacement penetration method, the complete uninterrupted penetrating process of jacked pile was simulated with the finite element method based on ANSYS. The soil’s displacement and stress field were obtained, and compared with the field test. The elastoplastic constitution law, large deformation, soil’s gravity field and pile-soil friction contact were taken into account. The difficulties and skills in the simulation were indicated, so it might be helpful to the other researchers.

Influence of the off line heating treatment parameter on the microstructure of a high strength steel plate was studied system previously. However, the information about the effect of on-line heating treatment process on ultra-high steel plate, especially on the plate with a tensile strength 980MPa or above, is limited due to the lack of effective method to simulation for the on-line heating treatment process. A method, which is preformed with a thermo-mechanical simulator, simulation the parameter of on-line heating treatment on the microstructure evolution a high strength ULCB steel plate after the accelerated cooling. By means of observation the original microstructure and microstructure morphologies varied with the parameter of the on-line heating treatment process, the present results demonstrate the microstructure characterizations before and after heating treatment process, while also the distribution of M(C, N) particles on lath boundaries or lath interior and the volume fraction and the average size of M/A island.

Tensile strength is an important material property and usually can be determined experimentally. The strain rate dependent behavior of T300 carbon/epoxy matrix composite was characterized over a wide strain rate range (10×10-5 s-1to10×104s-1). The low to moderate strain rate experiments were carried out on a MTS machine, while the high strain rate experiment was conducted with a split Hopkinson tensile bar. A rate dependent model was introduced to simulate the material response. Two kinds of stacking sequence of composite specimens [(45/-45)4]s and [(0/45/90/-45)2]s were tested at different strain rates, and the results were used to determine parameters of the model. The predictions of the model showed to agree fairly well with the experimental results. The tensile strength and initial elastic modulus of the composites increase when the strain rate increases.

The response of Carbon/epoxy composites under high velocity impact was investigated experimentally. The strain rate dependent behavior of T300 Carbon/epoxy matrix composite in tension is studied experimentally by split Hopkinson bar technique. Dynamic stress-strain plot was obtained and compared with the quasi-static tensile test results. The results of the study indicate that Carbon/epoxy composites are strain rate dependent materials. Stacking sequence has a significant effect on the material response. Tensile strength of the composites all increased with increasing strain rate. And failure strain decreased when strain rate increased.