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The aged crumb rubber modified asphalt (abbreviated as CRMA) was recycled with two methods which were adding fresh CRMA binder and adding recycling agent to investigate the recycling feasibility of aged CRMA binder. The performance of recycled CRMA binder was evaluated systematically with a variety of indices, including penetration, softening point, ductility and viscosity. The results indicate that the performance of recycled CRMA binder has good correlation with the content of the fresh CRMA binder or recycling agent. The performance of recycled CRMA binder mixing with the fresh CRMA binder or recycling agent with the optimistic content is improved and can meet the technical requirements. According to the relevant technical standards in “Guidelines for design and construction of asphalt rubber and mixtures in Beijing”, the index of recycled CRMA binder can reach the standard when the content of fresh CRMA binder is 70% or content of recycling agent is 6%. The experimental results show that the recycling of the aged CRMA asphalt is feasible.

Analyzed and calculated the energy savings of heat reflective coatings applied on multi-storied residential buildings and high-risen commercial buildings in Beijing. Some advices about the application of heat reflective coatings in northern cold region are given. Energy saving effect was evaluated with the building energy simulation in winter and summer while the heat reflective coating is applied on the surface of residential buildings and commercial buildings. Calculating results showed that the energy saving is the most optimal to the multi-storied buildings when the cool roof coatings is coated on the roofs and the glass heat reflective coating is applied on east and west windows. With the high-risen commercial building, the energy saving is noticeable when the glass curtain wall is coated with glass heat reflective coatings. The energy saving rate can reach a maximum of 13%.

Auxiliary power of Three-phase photovoltaic inverter is supplied by solar cells with wide input ranging from 140V to 1000V.The conventional single-switch flyback converter exists too high voltage stress in power switch to be applied in this inverter. This paper presents a dual-switch flyback converter in which the voltage stress of each switch is slightly higher than the input voltage when switches turn off, at the same time , the leakage inductance energy is recycled back into the inputside; otherwise, this topology needs no snubber circuit, so it is much more efficient than single switch flyback. The dual switch flyback converter with seven outputs is successfully applied in 10KW three phase PV inverter.

Complex operating environment makes excavator working device become the main wearing parts ,In this paper,builds three-dimensional models of the excavator working device using Pro/E. And selects the working device typical operating conditions which is in the maximum discharge height ,then imports it into the finite element analysis software ANSYS - Workbench module. For the purpose of acquiring its natural frequencies and mode shapes, it conducts the modal analysis by setting the material properties, meshing and boundary conditions,which provided foundation for the optimal design of hydraulic excavator overall vibration analysis and structural dynamic characteristics.

In order to detect target clearly, a detection system based on DM642 was designed. The system used improved frame-difference method combined with the background subtraction to detect target. First, the CCD camera scanned the surroundings step by step, then the background model was built, and improved three-frame-difference method was used to get the three-frame-difference image. The target image was the difference of target region extracted by three-frame-difference method and the target region extracted by background subtraction method. Experiments showed that the target image had less interference and a clear profile.

High-strength steel has a promising application due to vehicle mass reduction requirement while the high springback of forming and welding processes limits its application. Bending control and welding processes of ZQS700Z welded tube for automotive drive shaft are studied and the key processing technology is obtained. Weld microstructure analysis and flattening/flaring tests are performed and good performances are obtained.

This paper presents the research and development of a special self-contained Inclinometer based on the requirement of offshore platform monitoring. The device records the anchors inclination completely and accurately, providing information for stress analysis of the anchor chain. Laboratory calibration, platform movement simulation experiment, and real platform testing confirmed the instrument can meet the measurement requirements. The instrument is high-precision, energy-economical, mass-storage and user-friendly. Its able to work underwater continuously for up to one year. In addition, the small size minimizes the interference caused by the carriers motion. Compared with its foreign counterparts, the new instrument is inexpensive, so its suitable for extensive multi-point measurement. Now it has been installed in LH11-1 platform in the South China Sea for measurement of anchor chain inclination. Its the first time to employ measuring device with autonomous right in offshore platform monitoring in China.

The self-healing polymer material which was embedded microcapsules possesses the ability to heal cracks automatically. The microcapsules were synthesized by in-situ polymerization in an oil-in-water emulsion with urea and formaldehyde as the raw shell material,and epoxy resin (E-51)/ xylene as the core material. The impact of stirring speed on the morphology and particle size of synthetic microcapsules were discussed by optical microscopy (OM), scanning electron microscopy (SEM), and Fourier-transform infrared spectrometer (FTIR).Microcapsules of 400~1500 um in diameter were produced by appropriate selection of agitation rate in the range of 300~600 r/min.

Multi-core processor has been a hot topic since it improves operation speed. It is not easy to get efficient parallel processing data algorithms because of waste of hardware resources. In this paper, a novel multitask parallel algorithm based on getting common substring of two strings is described in order to improve the data-handling capacity of the multi-processor. Firstly, this algorithm performs Task Parallel Library (TPL) in VS.NET, and then schedule the algorithm proposed in this paper to process data. This algorithm is tested by actual parallel data. The results demonstrate that this algorithm overcomes the problem of waste of hardware resource, can take full advantage of the features of multi-core parallel processing data thereby enhancing the parallel speedup, greatly improving the efficiency of data processing.

The model reduction methods aim at simplifying system model while retaining system dynamic behaviors. In this study, an improved high-order system model reduction method based on modal aggregation is proposed, and which is applied to a typical complex mechanical system. Compared with general model reduction methods based on aggregation method, this method derived from the modal matrix can get more accurate aggregation matrix. The research on natural characteristic of gas turbine blade-disk shows that the reduced-order model obtained by modal aggregation method retains the dynamics of original complex system, which verified feasibility and effectiveness of the modal aggregation reduction method and also provided an easy method for similar simulation modeling and dynamic characteristic analysis of high-order complex systems.

Tension of mooring chain is the principle characteristic for mooring system. Tensile value which derived from on-site mooring lines could be used for risk assessment, design evaluation etc. It is hard to obtain underwater tension of mooring chain by traditional method, such as strain gauge, FBG, etc. A new tensile measure method is present based on finite element analysis and shape characteristics of stud-less mooring chain. At first, deformation of stud-less mooring chains is analyzed by finite element method and Ansys software. Then, a design of tension-meter is developed on the basis of the deformation characteristic due to the above FEM analysis. Finally, a model calibrate is designed and tested to prove feasibility of present measurement method.

To find the effects of pedoturbation on soil erosion of lands for agriculture and forestry in Menglianggu watershed of Linyi city from soil mechanics, shear strengths of 3 typical land uses (6 different soils) which are undisturbed and remolded respectively were measured by direct shear apparatus. Effects of particle size and binding materials on shear strength were analyzed by comparing shear properties of undisturbed and remolded soils with the same dry density, water content and vertical loads. The results show that all the angle of internal friction ( ) and most of soil cohesion ( ) of undisturbed soils are bigger than that of remolded soils; The final shearing stress also comply with the law above; The main factors affecting shear strength are soil particle size and binding materials.

It is widely accepted around the world that degree days should act as the measurement of HVAC energy in a given place. This paper makes use of the temperature data from 1985 to 2004 from 96 meteorological stations in Shaanxi Province. Based on the daily average temperature in some cities, counties and districts in Shaanxi, we work out the degree days. We divide different zones according to the normalized degree days from 1995 to 2004. In this paper, we analyze the distribution of degree days in Shaanxi, the changes in every decade, and the monthly distribution of degree days in Yulin, Yan’an, Xi’an, Hanzhong, as well as the changes of value in 20 years in Xi’an. At last, we figure out that Shaanxi has spread out its terrain in two climate zones: one is the cold zone; the other is the hot summer and cold winter zone. The HDD18 value has declined continuously in 20 years, and it drops 194.8°C•d/10a every year; meantime the CDD26 has ascended by 28.1°C•d/10a. In all the cities, the HDD18 value is the highest in January, and lowest in July. In the past 20 years in Xi’an, HDD18 value has dropped by 25.0°C•d/a, and the CDD26 has risen by 5.2°C•d/a, which are the highest among those cities.

Using cation amino polysiloxane emulsion(ASE) and anion carboxyl polysiloxane emulsion (CSE) as materials, mixing ASE and CSE together to self-assemble or aggregate by electrostatic interaction, supramolecular compound emulsion (ASE-CSE) was formed. TEM and particle size analyzer observation showed that the particle of ASE-CSE is sphericity, and its particle diameter is bigger than that of mono-composition emulsion and has single-peak distribution. SEM, atomic force microscope (AFM) and other instruments detections indicated that the ASE-CSE possesses good form-film property. The ASE-CSE film on the silicon wafer is very rough. There are many islands or peaks package on the film surface. The average thickness of the film is 12.45nm, and it is about 7.1 times as against ASE. With the ASE-CSE film, the stripes or grooves on the fiber surface is weakened or disappeared. And the surface is smoother than that of the control sample. In addition, the contact angle of the cotton fabric treated by ASE-CSE is 86.5°. This reveals that the ASE-CSE film brings fiber fabric from hydrophile to hydrophobe.

A mixed method to solve deep water S-Lay is presented. A singular perturbation technique is first used to determine the configuration of pipeline in the sagbend. The moment distribution of pipeline in the overbend is then determined by the nonlinear finite element method. The stinger is modeled as discrete supports in this study. Finally, an extensive parametric study is carried out to identify the optimal spaces of roller boxes for achieving minimum moment distribution of pipeline in the overbend.

This article proposed the adaptive harmonic detection based on artificial neural network，and which can test the amplitude and phase of all the harmonics. This paper also proposed the quasi-resonant control ratio strategy of active power filter. This strategy can compensate a specific harmonic of power system in real time, can achieve Static error-free control and with a strong ability of anti-grid frequency fluctuations. The results show that the method is feasible and effective.

A kind of carbon nanotube/expanded graphite (EG/CNT) was used as counter electrodes for the DSSCs following five different weight ratios of 1:0, 1:1, 1:2, 2:1, and 0:1. The impedance spectra and J-V curves were recorded using the Zahner Zennium CIMPS system based on an IM6x electrochemical workstation. The dynamic parameters of the cells were discussed with the intensity-modulated photo current spectroscopy (IMPS) and the intensity modulated photo voltage spectroscopy (IMVS) using white light-emitting diode (75w/m2, 604nm, LED) as the light source.

At present, developers can rapidly generate applications through Web service composition, the quality of service (QoS) of web service composition is important, but most of the existing composition methods are difficult to balance the QoS indexes (Such as time and price). In this paper, a web service composition method based on the price-time Petri net is proposed, the minimum cost can be obtained by modeling based on price time Petri net, and presents a method of priced state class to analyze the cost of web service composition model. Theoretical analysis and case analysis show that the price-time Petri net method is feasible to study Web service composition with the minimum cost.

ISODATA algorithm is capable of splitting and merging categories automatically. However, this kind of hard clustering fails to take into consideration the characteristics of image itself and human visual features. So its effect is generally not as good as that of fuzzy clustering algorithm. For most fuzzy recognition methods, if they are to be applied, the number of categories must be set beforehand. Besides, there is inherent defect in traditional Fuzzy algorithms. By contrast, intuitionistic fuzzy is a kind of improvement to make up the deficiencies of traditional fuzzy theory. Based on the advantages of ISODATA algorithm and intuitionistic fuzzy, with those critical functions which are related to membership and non-membership functions used as the measurement for clustering, this thesis is to propose a kind of ISODATA algorithm that is based on intuitionistic fuzzy, and to introduce membership function that has been improved for practical purposes. This kind of function takes region as the sample to be classified. Finally, this thesis is to verify the effectiveness of the proposed algorithm by applying it to Image Segmentation.

The performance of resisting foundation displacement of a typical single return circuit transmission tower under all kinds of load conditions including foundation horizontal displacement, foundation vertical uneven downward displacement was analyzed by finite element modeling. Results showed that stability failure of single steel angle represents tower’s limit state under foundation displacement. And the corresponding foundation displacement limits were calculated. Results indicate that foundation pull condition is more dangerous than press condition. Under complex foundation displacement conditions, foundation horizontal displacement is primary factor leading to stability failure of towers. Under foundation press condition and pull condition, wind load is primary factor. Result also indicates that, tower does not fail when foundation displacements are smaller than 1.25% (under foundation press condition and pull condition) or 0.5% (under single foundation sink condition) of tower root distance.

A superhydrophobic complex coating for cotton fabrics based on silica nanoparticles and new fluoroalkylsiloxane polymer was reported here. The complex thin film was prepared through sol-gel method using cotton fabrics as a substrate. Silica nanoparticles in the coating made the textile surface much rougher, and new fluoroalkylsiloxane polymer with reactive groups on the top layer of the surface lowered the surface free energy and enhanced the binding between silica nanoparticles and the fluoro-containing polymer. Textiles coated with this coating showed excellent water repellent property, and water contact angle (CA) increased from 138° on the pure fluoroalkylsiloxane polymer treated cotton fabric up to 156.5° on complex one. Moreover, this superhydrophobic complex coating possesses favorable washing durability and its CA still retain 106° after 20 times of soaping operations.