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For fast simultaneous localization and mapping (FastSLAM) problem, to solve the problems of particle degradation, the error introduced by linearization and inconsistency of traditional algorithm, an improved algorithm is described in the paper. In order to improve the accuracy and reliability of algorithm which is applied in the system with lower measurement frequency, a new decomposition strategy is adopted for a posteriori estimation. In proposed decomposition strategy, the problem of solving a 3-dimensional state vector and N 2-dimensional state vectors in traditional FastSLAM algorithm is transformed to the problem of solving N 5-dimensional state vectors. Furthermore, a nonlinear adaptive square root unscented Kalman filter (NASRUKF) is used to replace the particle filter and Kalman filter employed by traditional algorithm to reduce the model linearization error and avoid solving Jacobian matrices. Finally, the proposed algorithm is experimentally verified by vehicle in indoor environment. The results prove that the positioning accuracy of proposed FastSLAM algorithm is less than 1 cm and the azimuth angle error is 0.5 degrees.

The oxidation polymerization simplifies the brush plating process, by which a conductive polymer film is formed on Polyamide Engineering Plastics surface before direct brush plating. In the article, analysis is made on the various process parameters and the influence of the brush plating solution composition on deposition rate . And discussion has been done on the polyamide engineering plastics brush plating process , which includes three phases, namely preprocess, catalysis and brush-plating. the demand on brush-plating process is as following: The workpiece is connected to the positive; the working voltage is 14 V; the movement speed of the brush is from 0.04 m/s to 0.06 m/s; the temperature of brush-plating solution should remains at 80 °C; PH value is between 4.3 to 4.5.The test consequence shows that there are many advantages of brush-plating nickel-phosphorus alloy on the polyamide engineering plastics surface such as simple operating , brush-plating layer with high strength, no stripping and no cracks,and high abrasive resistance, all of which have greatly extended the life of polyamide engineering plastics service.

A film of Ni-P-Carbon-nanotube composite material is deposited on the surface of the metal substances by electro-brush plating. In this process, the composition of the Ni-P-Carbon-nanotube composite plating solution, the pretreatment on the carbon-nanotube and the effects on quality by the different brush plating technology conditions are investigated. The results shows that carbon-nanotube particles can be distributed uniformly in the coating by oxidizing, sensitizing and activating while the temperature of the plating solution should be controlled at 55°C, and PH value, 1.5~2.5. After the carbon-nanotube is added, the coating defects, such as the crack, the desquamation and the low bond strength, can be prevent effectively.

Modeling of the wind and PV hybrid microgrid is carried out by PSCAD/EMTDC. The model includes direct-drive wind power generator, Single-stage photovoltaic power generation system and storage battery. Simulate and analyze the operating characteristics of the microgrid running in grid-connected and islanding mode, which take into account the actual wind speed and light intensity. The simulation results show that the battery is able to regulate the voltage of the point of common coupling and smooth the power fluctuation of wind generator and PV generation system in the grid-connected mode. The microgrid can isolate itself from the grid in a rapid and seamless fashion when the battery adopting P/V and Q/f control strategy based on the droop characteristics.

Using the sodium citrate as ligands and adopting electric brush plating method, Re will be deposited together with Ni-P from the solution, and a complex brush plating of Ni-P-Re can be attained. It is discussed the effect of the rare earth Re3+ on the deposition rate, corrosion resistance and bonding strength of the Ni-P composite brush plating. Adding some appropriate Re3+ to the brush plating solution, the amorphous tissue can be obtained under the condition of the low phosphorus brush plating, which make the brush plating layer with high hardness and high abrasive resistance at the same time, binding force and corrosion resistance are improved, and greatly improve the performance of the brush plating.

Poly (p-phenylene terephthalamide) (PPTA) was synthesized by different processes including single feeding, batch feeding and inlet nitrogen cooling. The effects of these three processes on reaction heat removal of PPTA polymerization were compared. The degree of reaction heat removal was characterized through the changes of system temperature and stirring rate with reaction time. Results suggested that during the processes of batch feeding and nitrogen cooling, system temperature could be effectively decreased and PPTA yields were both larger than 98 %. It indicated that the exothemic heat could be transferred faster and better and monomers could completely react. The inlet incorporation of nitrogen cooling led to the maximum of inherent viscosity (ηinh) of resulted PPTA. This result indicated that nitrogen cooling could effectively transfer the reaction heat and prolong the gel precipitation time of PPTA.

The picture collected by CCD camera usually takes surface interference informations, such as pollution and surface reflection.etc, in the meantime because of being subjected to light source and CCD camera oneself intelligent degree the influence of etc. factor, the ineluctability exists some yawp voices in the picture.For the sake of convex leak parts of pictures now, have to clean yawp voice and interference information, reserve true leakiness trace. This paper filters a processing, edge to withdraw towards identifying according to the calculator fluorescence picture of picture, and picture ash degree two values turned the selection method and fluorescence signal calculation method of threshold value to carry on a study.To fluorescence oil liquid seep into the examination carried on an experiment research, the realization seeped into the quantity of quantity to turn a calculation, to seep into the quantity carry on a precision examination, and carried on analysis as a result to the test.

Related requirements about occupational health protective facilities and on-site verification points; requirements about occupational health protective system construction and verification points; requirements about corporate and labor rights protection and verification points.

It discussed repairing the worn engine crankshaft with chromium series metal powder-cored wire. The Mo, Mn, V, Ti metal powder and the SiC ultrafine particles, WC nanopowder added in chromium series metal powder-cored wire. That made the surfacing layer obtained high bonding strength, high hardness, and obtained high fracture toughness. The result indicated the SiC ultrafine particles/WC nanopowder could promotion the in-situ reaction in the surfacing layer, formed the dissemination strengthening, the melting strengthening and so on multi-mechanism strengthening effect. SiC and the metal matrix was not merely the mechanical bond, the partial regions were by the chemical bond. That realized in the structure continuity. And the repaired crankshaft surface wear-resisting disposition enhanced 24% than the original.

A wear-proof Cr/WC system surfacing alloy with flux-cored wire was developed by using a carbon dioxide gas shielded welding method. The wear-resisting property of the surfacing alloy was studied by analyzing the average hardness, the abrasion weight loss and the microstructure of the surfacing layer. At the same time, the influence rule of the alloying element in the flux core such as Cr , WC, Mo and V on the hardness and wear resistance of the surfacing layer was discussed systematically. Thereby the optimum concentration of alloying element was confirmed. The results show that when the content of Cr chemical element as 5.5%~6.0%, the content of WC powder is 3.9%~4.2%, the content of Mo is 1.6%, and the content of V is limited in 3.2%, the matching of the Cr/WC surfacing alloy with flux-cored wire is suitable, and the hardness and wear resistance of the surfacing layer is preferable.

The application and design of the Blackboard Academic Suite Database Analysis system based on MVC structure is introduced. The essential MVC structure and the development process of database model were also discussed in this paper. The system has been applied in practice and achieves very good results.

It is widely believed that Rankine cycle power plant using organic fluids as the working medium has advantages over conventional Rankine cycle with water steam as the working medium in low-to-medium temperature heat conversion. It is also testified in the market. However, besides the integration of the cycle and the characteristic of the working fluid, the design and debugging of the energy conversion unit are also important part in acquiring good performance. In this research some phenomenon of failure is investigated. Accordingly, the theoretical and practical reasons and solutions are obtained. It provides good guideline on the design and optimization of the energy conversion unit.

In this article, a series of the PVDF/PPTA blend membranes with porous structure and excellent performance were successfully prepared by the phase transformation method. The effect of the mass ratio of W(PVDF)/W(PPTA) was systematically investigated.The morphology of the blend membranes were examined using scanning electron microscope (SEM). The permeation performance was characterized by measuring pure water flux. Meanwhile, the mechanical properties of membranes were researched. The experiment results confirmed that the blending ratio is a major factor to influence the structure and performance of PVDF/PPTA blend membrane. The blend membranes possess much better permeability than pure PVDF membrane and fairly good the mechanical properties especially for the membrane made by PVDF : PPTA=6 : 1.

Development characteristics of oil field during production-decreasing stage were analyzed in this paper. The ultimate recovery factor can be determined at a limit of oil production rate by investigating the relationship between production rate and recovery percent. Some physical conditions were given. Based on the mass conservation principal and seepage mechanics method, it was found that the recovery degree varies versus production rate linearly. The model prediction using the actual data of west Ng63+4oil strata in Gudong 7 region, a reservoir in Shengli oilfield of China, was performed. The results demonstrated that the linear model had well estimation of the recoverable recovery of oil fields which were at the later period of high water cut stage.

The design of the solar LED street lamps based on MCU , which combines the MPPT of solar cells with PWM improves the reliability of the operating system of solar LED street lamps and extend the lifespan of the lead-acid battery , It adopt a controlling method for battery discharging process according to SOC of battery and the signal output of different PWM at different stages only to make the intelligent development of the solar LED street lamps uniquely advantageous and enjoy the better prospects of wider application.

A novel control system of Quad-Redundant generators with the CAN-bus communication network and nonlinear PID algorithm is designed in this paper. To enhance the reliability of this power generating units, a control strategy for the multi-DSC control network of four Brushless DC Motors is presented. The hardware platform of this structure is composed of host-computer, master controller and slave-controllers, on this platform every generator could be driven independently via the CAN-bus communication network. And the principle of the nonlinear PID parameters is proposed. Using this system, the control structure of generators could be simplified and the speed of communicating could be improved. At the end of this paper, the experiment results verified that the control system is reliable, the control strategy is rational, and the system has better dynamic response.

With the continuous development of terminal technologies, the use of mobile terminals is becoming more and more diverse. Many value-added services brought by such applications gradually become to be the firm's new profit opportunity. The location itself has great value; with the display of electronic map or with the support of geographic information database, a variety of information can be shown, tracked and handled. Such location-based services (LBS) is widely used in the field of public wireless data, and mobile location services is recognized as the most attractive wireless data value-added business in 3G network. This paper discusses three positioning standards of the 3GPP first; and then combined with the existing GSM/GPRS cellular radio communication network, it mainly gives specific positioning implementation strategies of single base station in the TD-SCDMA (Time Division Synchronous Code Division Multiple Access) system.

The two deposition polymerization techniques, i.e. vapor phase and liquid phase pyrrole deposition polymerization were applied to Ultra-high-molecular-weight polyethylene (UHMWPE) fiber in this paper. The effect of deposition technique on the surface morphology, mechanical properties, electrical stability and surface roughness of fibers were discussed. The result showed that deposition technique has a strong effect on the properties of UHMWPE fibers. Fibers treated by vapor phase deposition polymerization has much fine and small granular structure, lower resistance, better mechanical property and higher surface roughness value.

An amphiphilic graft copolymer was obtained via atom transfer radical polymerization (ATRP) of methacrylate (MMA) initiated directly by polyvinylidene fluoride (PVDF). Hydrophilic PVDF membranes were prepared by immersion precipitation of PVDF-g-PMMA and PVDF blend solutions. The chemical structure and the molecular weight were characterized by 1H-NMR and GPC. The hydrophilicity of membrane surfaces were characterized by static water contact angle. Top surface and cross-section of membranes were observed by Field Emission Scanning Electron Microscope (FESEM). The results demonstrated the water contact angle of the membrane surface decreased from 89°to 67°, indicating enhanced hydrophilicity; the pure water flux water firstly decreased and then increased up to 1.7 times of the PVDF membrane. The retention of PEG (Mn=6000) could be maintained at 93%-95%.

In this article we successfully prepared calamine / sodium alginate viscose fiber. Good dispersion and stability of the modified solution was prepared by dispersing calamine in alkaline solution of sodium alginate, and then mixed it with viscose spinning solution by spinning injection methods. Moreover, the stability of calamine / sodium alginate solution, the effect of concentration of calamine on the fiber properties is studied in this paper. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and physical mechanical performance are test to characterize the structure and the performance of the calamine / sodium alginate viscose fiber.

Taking reverse osmosis (RO) technology for the treatment of high salt containing oil waste water as the example, this study investigated the relationship between the pressure and the permeate flux, the stability of the membrane module and the membrane cleaning cycle. The results show the feasibility of RO technology for the treatment of high salt containing oil waste water.

Artificial lung also called as oxygenator which performs a function of exchanging O2 and removing CO2 from blood. Due to its good performance at the exchange area, oxygenation, etc, hollow fiber membranes have become the main research direction of artificial lung. Polypropylene (pp) hollow fiber membranes made by the melt-spinning and cold-stretching methods (MSCS) in this study. Through the research on the membrane manufacture process and technology optimization to prepare suitable membrane for artificially lung. The performance of membrane was affected by the melt-draw ratio and spinning temperature, annealing temperature, and the proportional relations of cold stretch with hot stretch. The results of the study show that improve melt-draw ratio, select the appropriate annealing conditions and the reasonable ratio of hot stretch with cold stretch can effectively increase the air flux of pp hollow fiber membrane.

In this study, polyvinylidene fluoride/liquid crystal polymer (PVDF/LCP) blending membranes were prepared via phase-inversion. LCP is ethyl cellulose (EC) dissolved into acrylic acid (AA). The properties of these blends were measured by differential scanning calorimeter (DSC) and polarizing microscope. The results indicate that LCP formed at the concentration of 0.60g/ml and the blends begin to be observed the presence of liquid crystal. Moreover, at a certain temperature range, higher temperature can quicken the formation of liquid crystal. With the adding of LCP, the cholesteric liquid crystal can be still retained in the blending membranes, but the solution enthalpy decreased.

A set of polyether-urethane block copolymers were prepared that poly (tetramethylene oxide) PTMO was regarded as soft segment, 4,4'-methylenebis(phenyl isocyanate)(MDI) and m-diphenylamine (MDM) was regarded as hard segment in this article. The microphase separation of polyether-urethane block copolymer was investigated by using infrared spectroscopy(FTIR), differential scanning calorimetry(DSC), small-angle X-ray scattering(SAXS),there obtained that there are two phases structure in polyether-urethane block copolymers and degree of phase separation decrease with increasing hard segment weight content.

The effect of acid modification using 1mol/L HCl on viscosity, thermal properties and mechanical properties of potato starch pastes and starch film were investigated. After acid modification, the surface of starch granules did not show more roughness and viscosity of starch pastes become lower. The results of DSC indicated that acid should act on amorphous region of starch firstly and would act on the crystallization region with the longer treatment time. In the very close viscosity scope, the mechanical properties of starch films were increased obviously after acid modification.

A large under-construction chimney at BALCO Power Plant in central India collapsed on Sep. 23, 2009 under severe stormy weather, causing serious casualties and massive economic losses, while another, similarly built, survived. So far, there has been no strict and scientific analysis on the cause of the accident. In this paper, finite element method is used to simulate the effect of wind loads and the whole collapse procedure based on the investigation of information about the design, the construction, the site related records, etc. The results show that the initial part of the chimney destroyed is the top of the structure (specifically the construction platform and the partial top cylinder wall of the chimney); then the debris from the top fells and crashes the lower part of the structure, eventually leading to the whole structure collapsing. The analysis results are basically consistent with the observation of the debris and the toppling scene and what the witnesses described, and scientifically clarify the actual cause of the chimney collapse. In addition, by comparing the chimney design codes between the USA and China, along with the analysis results, some suggestions are proposed to prevent similar accidents in chimney projects.

As a part of virtual simulation of construction processes, this paper deals with the quantitative risk analysis for the construction phases of the CFST arch bridge. The main objectives of the study are to evaluate the risks by considering an ultimate limit state for the fracture of cable wires and to evaluate the risks for a limit state for the erection control during construction stages. Many researches have been evaluated the safety of constructed bridges, the uncertainties of construction phases have been ignored. This paper adopts the 3D finite element program ANSYS to establish the space model of CFST Arch Bridge, and to calculate the linear, the geometrical nonlinear and the double nonlinear buckling safety factors under the six different lode cases. Then the bridge’s risks are evaluated according to the results calculated which provide a reference for design of similar project.

3-(trimethoxysilyl)propyl methacrylate was grafted into alkali treated poly(vinylidene fluoride) (PVDF) using free radical polymerization. 1H NMR, IR and DSC spectra of the modified polymer showed that double bonds were produced on PVDF and that 3-(trimethoxysilyl)propyl methacrylate was successfully grafted to PVDF. The membranes prepared using the grafted PVDF showed higher flux and better mechanical property than the pure PVDF membranes.

Polypyrrole (Ppy)-coated viscose fibers have been prepared by vapor phase and liquid phase pyrrole deposition technique, respectively. Comparative morphological and electrical property analysis was carried out on the viscose fiber prepared with both vapor and liquid phase processes. The result showed the configuration of Ppy coatings and electrical property had a strong relation with the deposition technique. Ppy-coated viscose fiber prepared by vapor phase show a high uniform polypyrrole coatings, fine Ppy granular structure, lower electrical resistance, and good fastness performances to abrasion.

Spot welding of magnesium alloy was a complex processes of thermal, electrical, mechanical and metallurgical mutual coupling, meanwhile its’ low melting point, high thermal conductivity, and high linear expansion coefficient increased the welding quality control difficultly. Basing on SYSWELD, a numerical simulation of effects of welding current, welding time, thickness of plate, electrode pressure gauge and size on the nugget shape and welding quality of ZA31B was demonstrated. The relationship between the size of the nugget dimensions and the welding parameters was established by a large number of simulation and experimental study. The experimental results showed that the analogue result was consistent with the test results, and it could be used to guide the actual production.

A pipeline robot is brought forward using the energy of fluid medium transmitting within the pipeline to perform the driving and timing. The robot is soaking in the pipeline full of flowing fluid medium and getting the driving force from the press and velocity energy of medium itself to push forward it. It is discovered during the research that robot need to overcome the gravity and influence of the friction resistance with the pipe wall while driving alone, so for the different mediums and applying situation the robot required to velocity adjustment automatically. According to the condition of the hydrodynamics within the pipe and designing in reason for the size and configuration of the robot, a velocity controlling device is worked out and realized its velocity adjustable.

Activated carbon filter is often used as the pretreatment process of nanofiltration or reverse osmosis membrane system, especially when the content of organics and free chlorine in influent water is high. However, a lot of microorganisms often rapidly reproduce in the activated carbon filter after continuous operation, resulting in a large number of bacteria in the effluent. So when the activated carbon filter was used as pretreatment of membrane systems, membrane fouling caused by biological contamination often occurred. The objective of this paper was to discuss how to effectively control the activated carbon biological contamination. Three different control methods—water backwashing, hot alkali treatment and ultrasound treatment were compared. Results showed that ultrasound treatment was the most effective. A relatively high removal efficiency of biomass (above 90%) was obtained when 40 kHz ultrasound was applied at 90 W for 20 min. Bacterial count in the effluent can be decreased from 3.90×104CFU•mL-1 to 8.5×103CFU•mL-1. After 3 days of continuous operation, bacteria count increased from 8.5×103CFU•mL-1 to 4.06×104CFU•mL-1. After ultrasound treatment, the removal efficiency of CODCr increased from -386.3% to 73.8%.

A novel submerged forward osmosis membrane bioreactor (FOMBR) is presented in this study. The selection of optical draw solutions for forward osmosis (FO) applications was developed and the Na2SO4 solution was found to be the most appropriate draw solution among five draw solutions for FO applications. The properties of two hollow fiber composite FO membranes, designated membranes A and B, which consist of an active layer formed atop a support layer, were prepared and utilized. Meanwhile, the water flux and removal efficiencies were evaluated in FO mode. Both of the FO membranes were found to reject greater than 95% of COD and 85% of NH3-N. Water flux changes suggested a better application with membrane A than membrane B for FOMBR.

Personalized recommendation methods are mainly classified into content-based recommendation approach and collaborative filtering recommendation approach. However, Both recommendation approaches have their own drawbacks such as sparsity, cold-start and scalability. To overcome the drawbacks, In this paper, we propose a framework for recommender systems that join use of Ontology and Bayesian Network. On the one hand, Ontology help formally defining the semantics of variables included in the Bayesian network, thus allowing logical reasoning on them. On the other hand, Bayesian network allow reasoning under uncertainty, that is not possible only with the use of ontology. In the recommendation, products not yet purchased or rarely purchased can still be recommended to customers with accuracy.

Based on the visualization technology, we investigated experimentally the effect of different flow patterns on anode fluid behaviors of the μDMFC (Micro Direct Methanol Fuel Cell) with a transparent material under the same condition. Stainless steel mesh was utilized as the current collector which was distinct from the carbon cloth or carbon paper. Four dissimilar flow patterns were developed and tested. The observation of the effect of different flow patterns revealed that movements of dilute methanol solutions and CO2 gas bubbles in the dot and parallel flow fields represented more difficult, which could result in a decline of the μDMFC performance. The study also showed that a channel blocking in the single-serpentine flow field would be extremely terrible which could lead to a fuels leaking of the μDMFC, meanwhile the liquid-gas flow was more fluent and stable in a double-serpentine flow field. Therefore, due to its advantages, a double-serpentine flow pattern is more suitable for the μDMFC application compared with the other flow patterns.

Polypropylene/polysulfone composite ultrafiltration membrane was prepared though coating method using microporous polypropylene hollow fiber membrane as a support layer and polysulfone membrane as a functional layer. Membranes of different pore sizes were prepared by L-S phase translation though changing the concentration of PS. The properties of the composite membrane include water flux and rejections of PEG-2000 were studies. The flux of 78 L/m2h and 98 % rejection was achieved at PS concentration of 11%, Polyvinylpyrrolidone of 4 %, liquid phase coagulation time of 3 hours.

Temperature and humidity independent control can be made by a new dry-type air-conditioning system, the combination of silica gel rotor and heat pump. Heat pump cycle can simultaneously cool the process air and heat the regeneration air, so it can cancel each other out in the cold and heat energy consumption within the system. This novel form of system not only solves the regeneration energy issues fundamentally but also avoids energy waste by reheating in conventional cooling dehumidification air-conditioning system. Based on the establishment of the component model, MATLAB program has been compiled to simulate the combined system running at nominal operating conditions and calculate the performance parameters and energy efficiency. Comparison of the energy efficiency was made of this dry-type air-conditioning system with ones of other regeneration desiccant wheel air conditioning system and conventional cooling dehumidification air-conditioning system, the results of which show that the new dry-type system provided regeneration energy, overcomes the restriction from climate, region and using conditions of other regeneration. Moreover, compared with conventional re-heat air-conditioning system, its energy saving is up to 35.1% and the energy efficiency is increased by 38.1%.