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Bolt as a connecting device plays more and more important role in various types of industry equipment. According to the needs of the domestic industry and on the basis of the automatic screw tightening control system requirements, this paper describes the design of screw-Machine electrical control system based on IPC independently.The main work probes into the electrical control system’s hardware structure and software structure.

Under the condition of high temperature, steel basic mechanical property index such as strength, elastic modulus falls sharply. Once there is a fire, long-span reticulated shell has serious damage. This paper, taking Kiewitt reticulated spherical shell as an example, uses ISO - 834 standard temperature - time curve to simulate fire and analyze the distribution of temperature field calculation and mechanical. Analysis by using transient thermal analysis in ANSYS software. Through ANSYS software to analog fire resistant properties of reticulated shell under the action of local fire resistant properties, it is concluded that the fire in the different parts of the structure on the structural deformation and destruction of the structure form, to a certain extent, reflects the overall structure fire resistance of spatial reticulated shell.

The most of Long-span stadium roofs are complex surface, the load norms cannot put forward the design requirements clearly in frequently. Determine wind loads need to use other means for help, while the numerical wind tunnel is one of the commonly be used to research methods in recent years. This paper introduces about the numerical simulation method of a long-span stadium roof surface wind pressure distribution , and based on FLUENT platform, a gymnasium as an example, the shear stress transport k - ω model (referred to as the SST k - ω model) on the roof surface wind pressure distribution of numerical wind tunnel simulation, analysis stadium roof surface pressure distribution law based on different wind directions.

Open ended cantilevered roof is different from enclosed roof, because its change of wind pressure distribution is complex, and the wind directions have great influence on it. Up to now, for the characteristics of the structure are very complicated, there is no appropriate wind load model can be used in design, especially under typhoon, a specific wind field. So it is necessary to study the characteristics of wind load on open ended cantilevered roofs of typhoon. Using FLUENT and Computational Fluid Dynamics technology, based on the conventional, Tianpu’s and Shiyuan’s turbulence intensity of the typhoon scenario, a numerical simulation of wind flow around a large-span cantilevered roof was carried out. Analyzed different wind angles of the wind pressure distribution regularities on large-span cantilevered roof. The paper determined the distribution of the surface wind pressure coefficient for the cantilevered roofs, as well as the wind-sensitive parts of structures.

The influence of the wind coefficient distribution on coal reservoirs for coal gangue is very important to its wind-resistance design. Take a real coal reservoir in Ordos for example, the wind pressure is numerically simulated with the help of Fluent Software. Because of the coal gangue piples, the average wind coefficient absolute obviously reduced under most of the wind directions, but the local area on the surface and leeward side the average wind coefficient absolute will increase significantly under the certain wind directions. Anyhow, the coal gangue is important to the wind pressure distributions of the coal reservoir and can't ignore its effect in the actual engineering design and should be given more attention.

Prestressing of lattice shell is realized by cable, and author put forward a new kind of layout: The prestressing has been brought to bear by hoop and radial element of single-layer lattice shell, which avoid cable's effect on architectural purpose. The element has been made to sleeve, and the magnitude of prestressing is dominated by bolt. Article shows an example of K6, K8 single-layer spherical lattice shell, and the prestressing have been exert on partial ribs and hoops. The prestressing has been calculated by element axial force under normal loading. Stability of shells have been studied, and show the deformation satisfy the criteria under normal loading; The ultimate capacity has been improved obviously, loads transfer is rational. The new layout of prestressing is a promising technique.

Sticker model is one of the main DNA computing models, whose features are that it does not require extension of DNA strands in the biological process, does not require biological enzyme action and also the DNA strands can be reused In this paper, we try to solve the general 0–1 programming problem by utilizing these features of the model and its four basic operations (merger, separation, setting and clear). The solution of DNA computing is put forward in [6] and [7], thus we use the method learning from [7]'s idea described in this article to go on solving.

Because of its low-cost low-volume and little power waste , The uncooled infrared detector has widely used in military and civil affairs. But the imaging quality of the uncooled infrared detector is degraded badly even the image is not identified when the ambient temperature of the uncooled infrared detector is above 60 or under 0.Aim at this problem, a method of the local temperature control of the detector was proposed to improve the imaging performance of the uncooled infrared detector when its ambient temperature had a large dynamic range. A heat insulation structure between the detector and the readout circuit and the temperature control circuit based on pettier effect are designed. The pettier is wrapped around the detector and the temperature sensor is set in the detector. When the ambient temperature of the detector is range from -40 to 20 or from 30 to 70 the control circuit work and It can keep the ambient temperature of the detector about 30±5 .When the temperature is range from 20 to 30the control circuit do not work. By this design the ambient temperature of the detector is controlled near 30,so the detector can operate in the optimal temperature point recommended by manufacturer and the image quality can be hold in well. Based on the Sofradir 320×240 microbolometer ,above-mentioned method is used and the test prototype is made. The interesting experiments are done and the experiment results indicate that the method is feasible, effective, and can obviously extend the ambient temperature dynamic range for the practiced application of the uncooled infrared detector. In this paper, firstly Relations between the performance of the uncooled infrared detector and the operating temperature were analyzed simply. Secondly the method of local temperature control and the principal on how to improve the performance are described in detail. Thirdly the test prototype is introduced. Lastly the experiment results are given and some conclusions are discussed. Keyword: uncooled infrared detector, pettier effect, microbolometer ,temperature control