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Urban spatial structure is the city in a variety of material, energy and social culture accumulation in space distribution and combination of the state. It is also the core issue of urban spatial development. Author studies China's urban spatial structure research, and find that China's urban spatial structure research mainly concentrated three times: 1980’s, 1990’s and since 2000.Research emphasis of each period is different. Through the process of urban spatial structure research, author sum up that the research in China has the following features: emphasis on urban spatial structure, advancing with The Times, etc. Authors hope this article can have the implications about the future of China's urban spatial structure research.

This paper aims to discuss what is the suitable scale of the specialized residential area for aged people. We used the method of combining the qualitative analysis and quantitative analysis, carded and compared the dates of the cognition and communication for the aged people, the walking range for the aged people, the walking range for pension service facilities, property management and relevant standards one by one, got the reasonable scale from two terms that is population scale and land scale. The optimum scale of the specialized residential area for aged people is population scale between 1000 to 2500 people and land area between 4.96 to 12.65 hectares. This data will play a guiding role for the construction and design of the specialized residential area for aged people in the future, and also will provide a reference for the planning and design of old settlements in urban planning.

The developing high-power laser systems are requiring higher laser-induced damage threshold (LIDT) and fabrication efficiency of fused silica optical elements. To solve these problems, MRF polishing and HF etching have been combined utilized wiping and passivating structural defects as well as removing impurities. Furthermore, the LIDT improvement is dependent greatly on the corporation of processes. But the LIDT improving mechanism is partly ambiguous yet, that may lead to random or experimental parameter choice and ultimately generate unsatisfied results. Consequently, this paper focuses on the termination mechanism of the process. Atom Force Microscope (AFM) measurement, finite difference time-domain (FDTD) simulation and LIDT test will be utilized to analysis and validate the optimization theoretically and practically. Finally, in one side, the LIDT value of optimized-terminated sample is 16.7J/cm2, which is about the same level (even 3.7% higher) as that of the over-etched one. In another side, the etching process time could be shorted by 32% using the optimized method.

Aiming at dealing with the problems of design, debug, and operation that occurred in the condensate polishing system, the paper put forward the problems of the high concentration of oxygen at the outlet of the condensate pump, pollution of the prefilter, the presence of remaining resin in the upper water cap of the high speed mixed bed, condenser leakage and abnormal shutdown of the turbine through the data analysis of condensate polishing system in Taishan Power Plant, diagnostic analysis of all these problems was performed and appropriate solutions were put forward.

The considerable variability of architecture and function realization of smart substation, which differ from traditional substations, makes the range of protection function check no longer restricted to one device, so it is necessary to carry out thorough monitoring and testing for various inks of functional implementation [1-2]. For this purpose, the automatic checking of protection functions for smart substation is researched, and a scheme for the implementation of the automatic checking is designed [3-4]. By means of adding various checking manners to application software implementation of the devices of protection system for smart substation, the checking and detection of various function implementation links of the protection system are performed, and by use of the expert system based on Dempster-Shafer theory a real-time virtual checking scheme is configured and through real-time analysis on checking information the conclusion of the checking is obtained. The proposed scheme enhances the self-diagnosis and self-monitoring ability of protection system for smart substation and gives full play to the superiority in digital information acquisition and information interaction of digital substation, so it can be used to the checking during on-site commissioning, besides, partial functions can be also used to perform on-line monitoring of protections being operated [5-9].

To provide UAV’s operator with flight information in real time, according to the property of remote control UAV and human-machine interface design, a flight controller has been implemented. The flight controller used LabWindows/CVI、GL Studio and UDP communication as the main developing platform. The system has been used in projection, and the test had showed that it could meet the need of the GCS(ground control station) of remote control UAV.

With the direction of large-scale, heavy machinery field, hydraulic system performance requirements also more and more high; This article is based on the mechanical and electrical integration of liquid hydraulic system test platform as the background, by the variable pump control motor speed control system as the research object, and describes the control principle of the system, established the mathematical model of the system, on the simulation software AMESim corresponding dynamic simulation model is set up, by changing the input variable pump rotation speed and system load test, and the output of the motor speed response has carried on the simulation, the simulation result in accordance with the expected on the trend of basic, therefore, the pump control motor speed control system between speed and power as a power source and load transfer mechanism is feasible.

Based on the movement characteristics,the four-bar mechanism of Micro-swing Engine was designed.The mechanism transform swing movement into rotary motion.With the kinematics model,the moving law of four-bar mechanism was analyzied.And simulate the machinery with computer to abtain the movement of curve of four-bar mechanism.The results show that the four-bar mechanism of Micro-swing Engine running smoothly and the inertia can be overcome the dead point.This will provides the theoretical basis for four-bar mechanism of Micro-swing Engine.

As a porous medium, the strength of cement-based materials is significantly affected by its porosity. This paper presents a new method to describe the strength development of cement-based materials as a function of porosity based on a developed microstructure hydration model of cement. The hydration model deduces the relationship between the diameter change of cement particle and time based on Krstulović-Dabić hydration kinetics formulas and extends a broader version by considering the effect of water reduction, temperature variation, interfacial contact area between hydration products and free water on the hydration rate. Using the hydration model, the time-varying development of porosity can be obtained. Then, based on the strength model proposed by Maekawa et al, in which both the present and initial porosity are taken into account, a new method was established to predict the strength evolution with the porosity calculated by the hydration model.

In this paper, the free modal of the industrial flat sewing machine was researched, and the experimental measurement system is established. A modal analysis of industrial flat sewing machine is carried out through the method of single point exciting vibration and multipoint collecting signal. The PolyMax modal parameter identification method is applied to the modal analysis for frequency response function to get steady state diagram and then determine the modal parameters and modal shapes. According to Modal Assurance Criterion (MAC), the credibility of the calculation results is verified, and then modal parameters of industrial flat sewing machine get more reliable in order to provide the reference for further structure optimization and noise reduction of the flat sewing machine.

Utilizing Socket Send () function to package the required CCP commands.Vehicle information terminal restore the data into CAN frames and achieve the purpose of remote calibration by parsing Socket nested word.Introduced the development of host computer for electric vehicles’ RMON .Including hardware configuration and development of the Information Center,the analysis of calibration database and the design of software for vehicles’ monitoring and calibration.Clarify the calibration process and fault diagnosis technology.

This work reports a cationic modified cellulose hydrogel for fluoride and arsenic adsorption. This adsorbent had a high efficiency in removal of F-, AsO2- and AsO43- simultaneously from aqueous solutions, even at low initial concentrations. Adsorption kinetics showed the relatively rapid rate to reach equilibrium, as could be explained by the pseudo-second-order model and the intraparticle diffusion model within 20 min before the equilibrium. Freundlich model could fit the adsorption process best, and the results showed the improved arsenic adsorption performances especially for AsO43-, much larger than other reported absorbents.

Machine working environment was simulated by using ANSYS software for analysis and calculation. Modal analysis results indicated that machine tools didn't produce resonance during the machine working. Harmonic response analysis result shew the displacement response frequency was 42Hz along the Y, Z two directions on the bottom of ram, and X direction's response frequency was 43 Hz. The conclusion given by this paper has guiding significance to use the machine safely in the future.

Fatigue failure of the mechanical parts has always been paid great attention to in mechanical engineering. In recent years the study on the self-healing composite materials with microcapsules provides a new way to solve it. In this paper, the fracture mechanics analysis on the self-healing composite material with microcapsules used for gear is carried out to determine whether it can achieve the self-healing. The results show that, only when the fracture toughness of the capsule shell and that of matrices matches in some way, can the self-healing be achieved. The composite material made of nylon 6 (PA6) as the matrix material, short E glass fiber as the reinforced material, poly ( urea-form aldehyde) encapsulated dicyclopentadiene (DCPD) as the self-healing microcapsule, is studied in this paper. The results show that this formula is feasible.

Because of the great advantages of savings for installation costs and areas of the ground, the ground source heat pump (GSHP) system combined with the ground-coupled heat exchanger with structural member is becoming more and more popular such as energy pile foundation etc.. However, the calculation method especially on the perspective of plate-type ground-coupled heat exchanger (PGHE) has not been established. This paper reports a study on a mathematical model developed to analyze the heat transfer of U-tube plate-type ground-coupled heat exchanger (UPGHE) which combined with structural member and an analytical solution is revealed. The results show that there are clear ‘heat submerge’ for the leg with lower temperature of UPGHE and it is more sensible to arrange one leg apart from another. The results also show that the spacing of pipes have obvious impact on the performance of UPGHE and the temperature difference between two legs have no important effect on the total performance of UPGHE.

In this paper, elastic modulus of core cell in x direction was built. Equivalent tensile/compressive modulus of core materials in y direction and equivalent Poisson ratio of core materials in yox plane were also built.

A new kind of polyamine salt inhibitor (code name BH-JAI) with low molecular weight, was synthesized and evaluated in the lab. The tests showed that BH-JAI could suppress the hydration and dispertion of reactive claystone effectively, compatible with organic salt or KCl water drilling fluid, and could play its role of inhibition even at temperature as high as 200°C. The field tested in 5 wells suggested that the new polyamine salt could enhance the inhibition ability of drilling fluids obviously, and reduce downhole complex accidents such as sloughing and tight hole efficiently.

Total of 40 soil samples were collected in vegetable garden soil in the urban-rural area of Fushun city. Heavy metal elements were evaluated including Cu, Zn, Pb, Cd , Cr, Ni, As and Hg. Soil environmental quality was evaluated by a combination of the single quality index method and the complex quality index method. Meantime, the soil potential ecological hazard was evaluated by Hakanson method. It will provide scientific basis for regional agricultural production, environmental protection and industry structural adjustment. The study showed that eight samples were contaminated by Ni, exceeding rate of 20.0%, and seven samples were contaminated by Cu, exceeding rate of 17.5%. In comprehensive study, light polluted accounted for 12.5%; warning and safety level accounted for 87.5%. At the same time, the order of the potential ecological risk of single-factor was Cd>Hg>Cu>Ni>As>Pb>Zn>Cr. Integrated potential ecological hazard was slight with the number of 25.48. Statistical analysis, correlation analysis and factor analysis all suggested that concentration of Cu, Ni, Zn and Hg were mainly affected by human activities, Pb, Cd, Cr and As were mainly controlled by parent rocks.

With the method of co-integration, the relationships between GDP and the total water use from 1980 to 2009 in the Weihe River basin are studied. The results show that there is a co-integration relation with a long time between GDP and the total water use.

According to the current national conditions and the intelligent communities’ requirements on the electric energy metering system based on the broadband power line communication (PLC), this paper introduces a design program for achieving the remote meter reading through the broadband PLC technology. The system takes the high-performance single chip microcomputer and the Ethernet controller RTL8019AS as the core, the low-voltage power line as the medium of data communication, and makes the electronic meters access to the Ethernet via the broadband power line, thereby achieving the remote automatic meter reading. The multi-functional low-voltage power line remote meter reading system constituted by this system and the backstage management system together will have broad application prospects. In addition, this paper also makes a preliminary study on the reliability of the meter reading system.

With the development of urban transportation, vibration and noise control has attracted increasing attention. Vibration and noise level has become one of the important hallmarks of evaluating the influence of urban transportation to environment. As Tuned Mass Damper (TMD) is an effective means of vibration control, there is more and more emphasis on its research and application. Reasonably designed TMD can reduce vibration and noise caused by wheel/rail impact. So how to take into account the complex factors to improve the design of the TMD is still the important issue. TMD system is an effective structure. In order to study its vibration reduction effect, modal calculation and wheel-set drop simulation have been analyzed in this paper. Through varying the mass of TMD, the performance of vibration attenuation have been verified. The stability and performance of damping property under impact load have been confirmed by wheel-set drop simulation. Comparing the track which uses TMD and the normal one, the effect of TMD system can be testified effectively.

This paper designs a new ultrasonic position and orientation model, further, a kind of technical scheme that can achieve the goal of large-range position and orientation system based on the designed model is proposed. Aiming at the designed model, this paper deeply analyzes the influence of distribution structure and physical parameters of the sensors on the position range, resolution and accuracy, which will provide theory support for developing high-performance ultrasonic position and orientation systems.

In this paper, cashmere knitwear is dyed at a lower temperature compared to conventional dyeing, and its physical and mechanical properties are analyzed and compared. The results show that cashmere knitwear dyed at low temperature can improve cashmere knitwear quality. It is also shown that cashmere knitwear dyed at low temperature can have improved physical and mechanical properties, especially its strength, abrasion resistance and pilling resistance.

In this paper, an integrated test system involving direct racking and simulation test systems is presented for evaluate the motion artifacts of flat panel display, to refrain from the high system requirements of direct method and environment limitations of simulation method. And then system structure and operating principle are expatiated and analyzed. Although the testing results are not exactly the same as subjective observing, they are still essentially homogeneous. Good statistical correlation illustrates the value of this study. The work presented here has implications for future contribution to research and measurement of motion artifacts of flat panel display.

In this research, an experiment was designed to study the capillary absorption of fly ash concretes. In order to understand the essence of capillary absorption, samples of fly ash concrete with different heights at different curing ages were tested in this experiment. It is found that the samples tested at 7d and 28d had the same sorptivity. And the height of the samples has no influence on the capillary absorption.

A turbocharging lean burn LPG engine combustion model is set up by using three-dimensional simulation software. And the numerical simulation of the engine working process is done. Based on the model validation, the effect of the engine working process is calculated and analyzed by comparing with different ignition models (single spark ignition and dual spark ignition) and the simulation results are validated by experiments. The results show that: dual spark ignition (DSI) model as compared to single spark ignition (SSI) model can reduce flame propagation distance, form the stronger swirl rapidly, accelerate the flame propagation speed, reduce knock phenomena, reduce the emission temperature and improve the engine efficiency. Therefore, the engine has better power performance and fuel economy.

Flat crush performance test, edgewise compressive properties test and sheering properties test of both ripple structure and latticed structure sandwich composites were performed respectively. Test value of elastic modulus was obtained. Contrastive analyzing the test value and calculated value, the correctness and feasibility of equivalent mechanical model were testified.

A turn rate estimation based adaptive interactive multiple model algorithm is put forward to solve model-set mismatch problem of target tracking algorithm applying to high maneuvering target. By considering both the estimation and the estimated variance of target’s turn rate, model-set is selected according to a rule based on the coefficient of variance of turn rate estimation. When turn rate estimation is acceptable, model-set is constructed according to turn rate estimation to reduce competition among models. When turn rate estimation is unacceptable, standard IMM algorithm model-set is applied to increase coverage of model-set. Simulation shows this algorithm improves tracking performance especially for high maneuvering targets.

This paper focuses on the methodology and dynamic system of New-town practice, which corresponds with the policy-oriented principle in Xi’an, and analyzes the relativity between the evolution of spatial structure and the influential factors such as the land usage, resources endowment, economic development, population growth, by studying the process of Xi’an Newtown construction over the past 20 years. Xi’an Newtown is attached to the main city area like a magnetic container, absorbing population either from urban or rural area. Furthermore, it is more like a huge magnetic field composed with multiple small poles. To some extent, New-town practice in Xi’an follows the policy-oriented principle, and meanwhile meets the goal of regeneration of cultural heritages, ecological restoration and low-carbon control. Yet it is very different from the experiences of building an anti-magnetic system of metropolitans in European countries after the World War II. Till now, seven relatively independent "edge cities" have came into being with new cluster centers and edge-economic growth poles, which effectively keeps the suburbs from spreading disorderly.

To study mechanical characteristics of general reinforced concrete in engineering, specimens of reinforced concrete with different mass ratios and specimens of fiber reinforced concrete with different distributing modes of steel fibers or mixed modes of fiberglass are produced. Testing results from these specimens state that recommended mass ratio is 1:4.29:0.74 of cement, sand to water for reinforced concrete, and mass ratio of mixed AR fiberglass is 4‰ or distributing mode of steel fibers is vertical 5 roots evenly for fiber reinforced concretes will have excellent mechanical properties. Analyzing mechanical indexes influencing characteristics of reinforced concretes, uniaxial compressive strength and ultimate strain are primary indexes, elastic modulus is an assistant index, and Poisson ratio and residual strength are both only referenced indexes.

Three-ply Kevlar fiber/epoxy composites used as static ring of ship propeller were manufactured by winding molding. The density of the composites was measured with a GP-300EW type density tester. Barcol hardness of the composites was measured with HBa-1 type Barcol hardness tester. The morphology of cross section of the composites was observed with a VNT-100 type metallography microscope. It was concluded that three-ply Kevlar fiber had low density and reinforcement effect.

Reaction kinetics of the esterification of Methyl Formate (MF) is studied in a batch reactor at different temperatures and the reliability of the estimated parameters is analyzed with Matlab using a fourth order Runge-Kutta method in the paper. Kinetic constants were experimentally examined and used to calculate the optimal operation parameters of semi-continuous reactive distillation for production of MF in order to minimize the amount of unconverted Formic Acid (FA) remained in the bottom. The results show that the optimal condition is obtained at the formic acid/methanol mole ratio of 0.5:1 and the mass fraction of formic acid at the bottom is 2% which is very close to the calculated value. Simulation work was carried out with Matlab and the results showed good agreement with the experimental data.

Boric acid (H3BO3) is often used for cooling the heat in nuclear power plant. Though the drastic measures have been taken, the potential leakage still can not be fully eliminated. Therefore, an attempt to understand the durability mechanism of RC subjected to boric acid is of vital importance. In this paper, specimens cured in a standard moist room at a temperature of 20 ±3 °C after 28days were immersed in three different concentration of boric solution (2000ppm, 8000ppm, 30000ppm) artificially simulated to accelerate the corrosion of acid environment. The hydration products are investigated. Microstructure of reinforced concrete on the surface, 2cm and 4cm away from the surface at ages of 60, 90 and 150 days are examined using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. Results indicate that main hydration product is Ca(BO2)2,boric acid corrosion to concrete surface can only be detected from the specimens in 30000ppm solutions at the ages of 150 days and its effect is slight. However, the inner part of the concrete was not affected. The results of XRD coincide with those of SEM.

Cement concrete has an increasing utilization in highway construction. However, the lower flexural tensile strength and abrasion-resistance restricted the development of concrete pavement with heavy traffic. Hence, It has highlighted the need for research on high performance concrete (HPC). The design of specific concrete normally depends on the mixing of mineral admixtures in concrete mixture. This paper presents the first experimental study on strength and abrasion-resistance enhancement admixture (SAEA) mixed with slag powder, steel slag powder and silica fume. The optimal proportion of three mineral admixture and reasonable mixed amount of SAEA were then given, and the mechanism of SAEA reacted in concrete was analyzed based on sol-gel theory. Lastly, the effect of concrete mixed with SAEA was validated and the micro-structure transformation of specimens was given by SEM.

Based on the MFPA2D software system and test method of the wedge splitting fracture in the Lab., a numerical model was established. The numerical experiments on wedge splitting fracture with plain concrete and SFRC (steel fiber reinforced concrete) were carried on. The calculation results about plain concrete with different dimensions and ligament length proved the numerical model is effectively on numerical calculation, and have a good agreement with the results of the test results. Then, the process of crack initiation, propagation of SFRC specimens with different dimensions and fitting formula about size effect were given. The results indicated that the size effect existed in the splitting fracture energy of SFRC.

This paper reports the investigation on both high and normal strength concrete using a non-contact electrical resistivity facility. The bulk resistivity development (ρ(t)-t curves) of the fresh concretes was evaluated from casting to 72h. The relationship between the electrical resistivity and the pore structure obtained from mercury intrusion porosimetry (MIP) method was analyzed. And the compressive strength evolution of fresh high- and normal- strength concrete was studied based on the bulk resistivity at early ages. The experiment results indicated a linear relationship between the fractional porosity and electrical resistivity. A further correlation between the compressive strength and electrical resistivity was analyzed with Archie’s law. Based on these studies, it appears that the electrical resistivity test could provide information for the design, quality control, quality assurance, and utilization of both high- and normal- strength concrete.

Reaches on durability of concrete has been made great advances over the past decades. However, little works have been done on the corrosion of reinforced concrete exposed to boric acid in cooling pond of heating exchange system of nuclear power plant. The purpose of this study is to experimentally investigate the behavior of reinforced concrete in such circumstance. Tests were carried out on specimens cured in a standard moisture room at a temperature of 20±3°C. Three different concentration of boric solution (2000ppm, 8000ppm, 30000ppm) were simulated to accelerate the corrosion. The compressive and splitting tensile strength,elastic modulus of concrete , mass loss rate of steel bar, bond strength and flexural bearing capacity of reinforced concrete at 60, 90, 120, 150 and 180 days were obtained respectively. The results indicate that the presence of boric acid below 30000ppm does not significantly affect serviceability of concrete. The corrosion is slight for the specimens with crack less than 0.4 mm under flexural loads. Boric acid almost has no effect on the corrosion of the steel bar and bond strength.

A three-dimensional mathematic model is developed for a 100kw single-end recuperative radiant tube and the simulation is performed with the CFD software FLUENT. Also it is used to investigate the effect of distance between combustion chamber exit and inner tube on heat transfer process. The results suggest that the peak value of combustion flame temperature drops along with the increasing of distance, which leads to low NOX discharging. Also radiant tube surface bulk temperature decreases, which causes radiant tube heating performance losses.

Friction and wear performance is very complex. There are many tests methods and tests apparatus. In this paper, some basic of friction contact types and relative motion modes were introduced. Then some important friction tests methods and apparatus for composites were reviewed concisely. At last, a new friction method and equipment used in Kevlar/epoxy composite were proposed.