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Purlin connections have important influence on the stiffness, bearing capacity and the purlin calculation methods. A new kind of purlin connection was put forward in this paper. The mechanical behavior of the new connection was studied by finite element analysis using software ANSYS. As can be seen from the simulation results, the new connection can enhance the stiffness of purlin, and effect of each new wave connection is better than the promotion of purlin stiffness in the vibration wave connection. New connection has a better promotion effect for small stiffness of purlin.

The simulation of Profiled Steel Sheeting-concrete Composite Slabs is based on ABAQUS,the finite element simulation software.The simulation is compared with the test to verify correctness of the finite element simulation method.By changing shear connectors of composite slabs, studies are performed on the influence of shear-bond property ,the behavior of slip between sheeting and concrete,slip distribution along the composite slabs and so on.The results indicate that setting shear connectors ,such as shear reinforcement and studs, can improve ultimate bearing capacity and reduce the slippage between the interface.The studs’ effect is more obvious.Actual engineering should select suitable shear connectors,so that it can meet the strength requirement and be economical.

This paper puts a form of reinforcement with used finite element methods to carry on the numerical simulation of a new type reinforcement form of light steel ceiling. Compared with the ordinary ceiling, the new reinforcement form of light steel ceiling can greatly improve the capacity of the ceiling sideways resistance with the overall strong stiffness from the simulation results.

In the decoration integration of steel structure, overhead floor achieves a separation of decoration and structure. Overhead floor system is composed of steel bracket, beam and floor. Reasonable overhead floor structure to ensure the safety of the whole structure has important significance. In this paper, the new form of beams named the cold bending cap steel is proposed and the size design of the new beam is made. While maintaining the original beams on the basis of mechanical properties, the new form of beams increase effective use height above the floor. In addition, the construction technology, construction requirements, the error control of overhead floor system, etc. are summarized and some author's suggestions in terms of modular are made.

Current steel structure design software cannot calculate sectional properties of user-defined section of cold-formed thin-wall steel accurately. Since the sectional properties data given by design code has been implanted into corresponding modules of these software and the software disregard the radian of corner of steel, erroneous results will be generated if the user-defined sectional size doesn't match the sectional size of the data file implanted. According to Green's theorem, the author derived precise formulas for sectional properties of arbitrary section and developed software for calculation based on Visual C++ platform. The software which can calculate exact solution of sectional properties of arbitrary section has been verified by comparing results from various methods. This software can be used independently as a calculating tool and the calculation module can be implanted into other steel structure design software to make calculation for sectional properties of arbitrary section possible.

Accurate temperature measurement needs in both research and industry have become more demanding and traditional temperature measurement technologies are struggling to keep up. Optical fiber thermometers have many unique advantages and are an option with much potential in the area of high temperature measurement. Research shows that fiber optic temperature sensors are capable of making accurate and precise measurements in a wide range of harsh conditions where other measurement technologies cannot and are a cost effective option in situations where traditional measurement technologies are currently used. Several typical high temperature fiber optic sensors are discussed in detail, focusing on the principle of operation, advantageous characteristics, and recent research developments, with the aim of aiding in further work with fiber optic thermometers.

In order to ensure proper temperatures for electronic equipment and to meet the increasing heat dissipation capacity needs of airborne electronic equipment, a suitable heat-pipe for use in aircraft equipment needs to be found. Considering both the acceleration and the changes in tilt angle of the aircraft, performance analysis of five main types of heat-pipes showed that dual compensation chamber loop heat pipe and micro-channel plate heat pipe were the most suitable for use in airborne electrical equipment.

This design is an implementation method based on the "automatic obstacle avoidance car", which gravitational potential energy can be converted into mechanical energy and driving as the motivation .This car can automatically avoid obstacles on the track settings in advance. The greatest feature of the car is during its operation, accelerating first then maintaining a constant speed, so that less energy consumption are required. Besides that, the walking track is closing to the sinusoidal curve. The convenient manufacture has a simple structure as well as high transmit efficiency.

Cold bend section forming is generally completed by multi roll pass. The whole rolling process form chain structure. Applying virtual manufacturing technology to cold bend section production field is a new concept. Aiming at the chain of the specific conditions of the rolling process, the paper studies the application of virtual manufacturing technology implementation method and puts forward a new concept and technical measures.

Welded pipe and special pipe get more and more applications; however, the difficulty of pass design method limits welded pipe manufacture. The paper discusses welded pipe roll pass design method based on CATIA, and roll CAD/CAPP computer aided design system based on AutoCAD, and gives roll virtual design methods which use roll CATIA, CAD/CAPP system.

Enterprises have been looking forward to breakthroughs of compound cold rolled section steel precise pass design algorithm for a long time; the breakthroughs will enlarge the application area of cold rolled steel. However, further study of stress and strain cannot effectively conduct pass design algorithm, the theory research and pass design have bottlenecks. Use spline finite strip method to guide pass design, with artificial intelligence correction, we can gen precise pass design method. These researches will offer theoretical foundation to precise pass design and pass software design.

In order to ensure H-beam’s organization and performance requirements, there is a certain compression ratio from the rolling of the billet to the finished product. This paper select rectangular billets and use DEFORM finite element software to simulate and analyze the rules of stress variation when rectangular billet is cogged down. The simulation results show that: from rectangular billet to finished product, the compression ratio is 17.4 and after cogging, billet size meet the requirements of the CCS rolling. The equivalent stress of breakdown rolling is mainly concentrated in the waist or in the junction of waist and legs. In the first few pass，equivalent stress is mainly concentrated in Sharp-angled position of both top and bottom, however the next few pass’s equivalent stress is mainly concentrated in the junction of web Plate and flange.

How to build a stable pipe roller design algorithm system has become the difficulty of modern steel pipe roller design. Although the theory researching cold bending forming is more now, but the theory used to guide pass design is less. This paper studied and established the new rolling process model based on spline finite strip theory. It’s good to Shape the way time and build the chain storeing deformation way Agent structure in transition region. It helped to realize intelligent single channel cold bending forming a stress and strain description. And it is usefull to establish forming theory and the parameters contact of the pass design. In a word, it provided the theory basis for the precise pass design.

The drying section of paper machine is not only the major energy-consuming parts of the papermaking process, but also one of the main bottleneck restricting the speed, yield and paper quality. So the research on the drying section has attracted much attention at home and abroad. In view of the traditional steam dryer shortcomings, this paper first introduces two kinds of improvement measures —— the tubulator bar and the siphon which can improve the efficiency of the traditional steam dryer. With the development of the paper industry, domestic and international research on the new type of paper drying technology has achieved some success. Then, we analyse their working principle and characteristic, and conclude that multi-channel dryer has a broad research and application prospects.

Single-phase β-Sialon ceramic compacts with z=2 have been synthesized by reaction-bonded sintering using Si, Al and Al2O3 as raw materials. After post-sintering at 1550°C for 2h, only β-Sialon ceramic compacts with z=2 was obtained. When the temperature up to 1650°C and 1750°C, the decomposition reaction of samples was occurred.

In order to control the greenhouse system of temperature, humidity, the concentration of carbon dioxide and some other environmental parameters during the plant seedlings process, design a greenhouse real-time monitoring system by using a PLC module, this system can realize the function of controling the various environmental parameters during he plant seedlings process to achieve the best environment plant growth process requirements.

The loosely-coupled reconfigurable computing model includes the host microprocessor in conjunction with an external stand-alone reconfigurable hardware which takes advantage of low cost in technology and development time. It can work as a fast emulation approach to study reconfigurable computing prototype system. One of the key features of such emulation system is the ability to perform the communication. In this paper, we proposed a high speed hardware channel with direct memory access(DMA) transaction method based on Xilinx ML555 development kit and PCI-express(peripheral component interconnection express) endpoint block IP. Experiments show that both read and write transaction speed in this design meet the theoretical maximum speed.

As important parts of airship’s control systems, the attitude control and station-keeping control have important effects on the vehicle’s performance. This article discusses the control methods in present usage, which include PID control, robust control, optimization control, sliding mode variable structure control, auto-disturbance rejection control and other control methods. The application areas of the methods are discussed, and the developing direction is pointed at last. Introduction

Aiming at the requirements of autonomous control for stratospheric airships, based on description of the modeling plant and forces analysis in detail, the dynamic model is established by Newton Method. The motion characteristics of airships under control action are analyzed using simulation method. Simulation results indicate the correctness of dynamic model, and can make itself a theoretical basis for the overall design of the stratospheric airship.

Cold-bent section is one kind economic section molding of low energy consumption and high benefit, it is widely applied in the construction, the astronautics, the light industry and so on many fields. Deformation mechanism of the cold- bent section is extremely complex, relations of deformation strength and energy and steel belt deformation can not described by the simple function. Thus leads to complexity of the roll pass design. Establishing multi-Agent system corresponding with the steel belt characteristic finite strip sets, Introducing characteristic multi- Agent model strategy can intelligentize the condensing data, thus can realize the roll pass design intelligentization.

Antennal olfactory responses of the parasitoid, Apanteles sp. (Hymenoptera: Braconidae), to 13 host-induced volatile compounds were measured by electroantennogram (EAG) techniques. Dose response curves of EAG indicated that compared with males, females showed significantly stronger EAG responses to (Z)-3-hexenal, (E)-2-hexenal, (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, (Z)-3-hexenyl-hexanoate and Benzyl nitrile. Among plant volatiles tested, the females were most sensitive to 100μM (Z)-3-hexen-1-ol, while the males were more sensitive to 100μM (E)-2-hexenal. The results show that the wasp is able to detect all compounds tested. We detected no sexual differences in the EAG responses to (E)-2-hexenyl hexanoate, (Z)-3-hexenyl benzoate, (Z)-3-hexenyl-2-methyl butyrate, (E)-β-ocimene, Linalool and DMNT.

Currently, the continuous rotary north-finder is widely discussed for its outstanding performance. However, few researches on the influence of turntable error to the continuous rotary north-finding algorithm can be found. Turntable errors, such as the stability of rotate speed, the periodic angle measurement error and the discrete angle measurement error, are studied for the north-finder based on rate biased RLG (ring laser gyro). Two north-finding algorithms are designed, which can restrain the influence of angle measurement errors and the stability of rotate speed separately. Finally, simulation and experiments are performed to verify the algorithms.

In order to establish and analyze the categories and application status of energy-saving products of building envelope in northern China, especially in severe cold and cold climate zones, the categories and statistic data of building envelope in northern China is gained in the classes of wall, door and window, through the way of referencing from the relevant literatures and data, investigating and visiting companies. The comparison and analysis of the date shows that the building envelop in northern China can basically meet the design requirement of heat preservation and energy-saving in severe cold and cold climate zones. Traditional products of building envelop are suitable for the multiple requirements and energy-saving need of modern architecture. Further research and development of new materials and technologies is needed but the restrain and lack of standardization in existing market should also be taken into consideration. The categories and statistic data in this paper play a reference role to other scholars and designers for researching the building envelop in severe cold and cold climate zones.

The primary program development principles and techniques of detailed drawings and CNC programming based on three-dimensional solid model for light gage steel structure are discussed. Components of the structure with complex spatial relationships and construction details are shown directly, accurately and completely based on 3D solid model, and structure properties and design requirements are integrated into the intelligent model. Therefore, drawings and detailed drawings can be drawn and labeled automatically by projecting and hiding with the extracted geometric information of particular entities. Further more, an automatic programming method for computerized numerical control is proposed, and CNC program are encoded according to manufacture information of parts in the model.

The influence of citric acid on phase evolution of calcium phosphate is studied by the electrical conductivity of reaction solutions. The conductance curves are divided into three distinct regions and assigned to the formation of amorphous calcium phosphate (ACP), hydroxyapatite (HA) and the solubility of HA, respectively. When more citric acid is added, the width of region I decreases because moreCa2+ions would prefer to foster the nucleation of HA from ACP. Decreasing rate of conductivity in region II becomes smaller with more addition of citric acid because the supersaturation of HA decreases in solutions. And thus, HA powders with larger grain size are synthesized with more citric acid addition.

By means of analyzes the differences of mechanical properties between railway wagon with cold bending centre sill steel and common cold-formed steel, to study the differences resilience by different materials, final this given the forming principle and molding pass of cold bending centre sill. Analysis the stress state of the forming process of cold bending centre sill with multiAgent technology, establish corresponding Agent force model. In determining the basis of forming passes, then determining the deformation per passes and the amount of bended, furthermore realized the forming process of virtual in computer.

Surface accuracy measurement of a 1.5m-diameter novel inflatable antenna formed by 18 aluminum-coated Kapton® gores is investigated using digital photogrammetry. More than five hundred 3mm-diameter round retro-targets were glued on the surface of the antenna, and their 3D coordinates at different internal pressures of the antenna were obtained using V-STARS digital photogrammetric system. According to the measured data, the influence of internal pressure of the antenna on its surface accuracy was analyzed, and the deviation of gores’ center line and ribs on the surface were also studied. The results show that the internal pressure has significant influence on the surface accuracy of the antenna, especially near the antenna’s dome.

In order to design a set of geostationary meteorological satellite data processing system，which have common data processing，practical remote sensing products and rich visual stylet，used VC++6.0 MFC and dynamic link library and the mature remote sensing products processing algorithms, to design it. Multi-satellite source geostationary meteorological satellite data are integrated, remote sensing products are generated, for example, cloud detection, cloud classification, cloud top height. The original cloud image, remote sensing and geographic information products are displayed vividly. The three-dimensional cloud image processing retrieval based on cloud detection product takes into account the visual effect, and also has a clear physical meaning, practicality is strong. The system makes geostationary meteorological satellite information play a more important role in the current weather forecast.

With the development of computer science, the finite element method has been used widely. The paper used the ABAQUS finite element analysis software to carry out the finite element analysis on the middle long columns of high-strength concrete filled square steel tube with inner CFRP circular tube under compressive load. The results of finite element analysis were obtained, which agreed well with theoretical data. This conclusion proved the correctness and feasibility of finite element model.

The elastic and plastic characteristics of the Y-joint of frame-core tube structures with steel pipe column and steel pipe outrigger truss is studied in this paper. The finite-element method is adopted in the numerical study. To avoid the damage of the joint, controlling the relatively convex-concave deformation of the column wall through adding internal stiffener plate is discussed. Through the comparison of numerical study of the Y-joint with different shape of stiffener plate, a feasible design of the Y-joint is given.

The dynamic behavior of gangue concrete filled circular steel tube beam with different steel ratio under the cyclic loads are analyzed and studied based on finite element analysis software ABAQUS. Through reasonable modeling established, parameter set, an effective grid meshed, the hysteresis curve of gangue concrete filled circular steel tube beam under low-cycle reversed loading is given, and verified compared with the experimental results. The comparison shows that the simulated hysteretic curve gives results in close agreement with the experimental results. The simulated curve shows that there has the characteristic of spindle-shaped and no significant decline in stiffness of the hysteresis curve. And the fatness of hysteresis loop is better.

Li-Ti-O (abbreviated as LTO) nano-composites were synthesized via sol-gel process, and then doped BaTiO3 based X7R type ceramics. The LTO nano-composites and their ceramics were characterized by means of thermaogravimetric, Fourier-transform infrared, X-ray diffraction methods, transmission electron microscopy. We also characterized the dielectric properties of the LTO doped BaTiO3 based ceramics of X7R type. The results indicated that LTO nano-composites were nanometer scale powders. The pH value and calcining temperature had an influence on particle size of LTO sintering aids. At pH about 3 and with calcining at 600 °C, the nano-composites attained minimum particle size (about 10 nm). By adding 0.10 wt% of the LTO nano-composites, the temperature permittivity achieved about 4200 when sintered at 1240 °C for 4 h, and the dielectric properties met X7R standard.

Steel portal frames have been widely designed and constructed in China since the end of the last century, and in recent years ERP management software systems have been used by more and more steel structure fabricators/constructors. This paper introduces the program principles and techniques of the development of integrated CAD software with ERP interface for the detailing design of steel portal frame structure, including the frame work, data structure, 3D modeling algorithm and automatic output of 2D drawings/ERP source data. In the system, steel members and connectors are modeled and visualized as 3D objects. All information, involving geometry, material, manufacturing, fabrication, installation, ERP data requirements and so on, are embedded in these 3D objects for the purpose of parametric modeling and subsequent data output. 3D solid model acts as the kernel of the system. Connectors of joints are classified and organized by way of logic hierarchy, 3D model of joint are assembled abide by the structural and geometric dependency relationship between connectors. The ERP data interface is embedded in the system. The raw data are directly extracted from the 3D model, then formatted and fed to certain ERP system.

Sun-valley of Expo-axis is irregular large-span steel structure building. For the complicacy and specialty of tubular joint conformation, existing domestic and oversea professional software are incapable of solving the detailing work of this structure. Characteristics, difficulties and function requirements of the engineering are analyzed; the framework, data structure kernel and implement algorithm of important functions are designed for a specialized integrated detailing/manufacture CAD/CAM information system. This software comprises the functions from 3D solid modeling to automatic output of shop drawing and NC data, and it has been successfully applied to the actual construction work of sun-valley project.