土地利用动态监测中多源影像融合方法的比较研究--以陕北黄土丘陵沟壑区为例

在陕北黄土丘陵沟壑区,采用单一传感器的遥感影像提取土地利用信息,存在着识别的土地利用类别少、某些类别混分现象较严重、分类结果的精度较低等问题。以TM多光谱数据和SPOT全色光谱数据的融合为例,提出了适宜于该地区的两种影像融合方法:主成分变换法和乘积运算法,并从影像的光谱质量、纹理信息和目视效果等方面对其进行了对比与评价。结果显示,主成分变换法为较理想的融合方法。以陕北无定河流域为实验样区的土地利用自动分类结果表明,该方法的应用使土地利用各类别的提取精度都有不同程度的提高;水体、水田和城镇用地等面积较小的类别分类正确率提高达到10%以上;坡耕地与林草地的混分明显减少,分类精度均提高了5%以上;分类总精度从82.0%提高到89.2%,取得了良好的分类效果。此研究对于遥感影像融合技术的评价与应用进行了有益的探索,同时为该地区的土地利用动态监测提供了关键技术。     

磷化铝动态潮解膜下环流熏蒸生产性试验

磷化铝动态潮解法是配合环流熏蒸使用的一种新型施药方法，本试验结合我库的具体情况，将动态潮解与膜下环流熏蒸有机结合起来，有效地解决了仓房气密性、有效时间、害虫再次感染等问题，大大提高了熏蒸杀虫效果，为抗性害虫的综合治理探索出一条新路。     

Application of Multi-vertical-line-element Model of RC Walls and Discussion on IT

The inelastic dynamic response analysis program for frame-shear wall structures developed by the authors is introduced firstly, in which the multi-vertical-line-element model was adopted for shear walls and the refined single-component model was used for beams and columns in frame.By analyzing three-story structural models tested in shaking-table in a famous foreign research institute, the validity of the modeling of shear wall in the program was verified. The analytical results indicate that the inelastic dynamic responseof shear walls under random ground motion input can be predicted effectively withthe program. Finally, with the preliminary discussion of some key points in modeling of shear wall, some suggestions areput forward for further improving and refining the multi-vertical-line-element model.     

Analysis and FEM Simulation of the Forming Process of Front Bumper Bracket

The processing characteristics of the front bumper bracket are analyzed,and a reasonable process scheme is worked out.The three-dimensional sheet metal forming analysis software PAM-STAMP are adopted to simulate the bracket's drawing process.Then the surface of die is proved fine through analyzing the FLD diagrams and the forming results.An economical and optimized die structure is decided,and a complete set of dies of the bracket is designed.The spacing block is added in the sizing mold,which control the size precision of end products and assembling columns actively,and finally the certified products.The material utility and the labor productivity are raised,the production cost is saved,and the mold design quality and the efficiency are improved effectively.     

Two Types Modules for the Boiler Attached to 330 MW Unit

Boiler is an important facility in power plant , the safety and economy of unit is affected by it. Studying the dynamic of boiler can improve the knowledge about boiler , which is important for. Features of MMS are introduced based on MMS simulation setting, and the real time capable module and non real time capable module are compared from principle. Real time capable dynamic model of boiler and non real time capable dynamic model of boiler of 330 MW unit are established . The experimental results show that the dynamic process of two type model accords with the mechanism of the object , at the same time, the validity of real time capable module is discussed .     

Simulation for Logistics in Steel-making Process of Panzhihua Iron and Steel Corporation

To solve potential scheduling problems in production after renewal of continuous casting process in Vanadium-extracting and Steel-making Plant of Panzhihua Iron and Steel Corporation (PISCO), how to model and simulate logistics system in steel-making processhas been discussed. A series of simulatingtests for logistics system in steel-making processhave been conducted based on inputs of presentsteel-making processof PISCO. In the tests, cases of regular schedule case and cases with repairing converter have also been regarded as essential simulation condition. It has been shown that three casters can not start at same time in order to ensure continuous hot metal supply for casters when three kinds of steel are made. It has also been shown that the simulation system for logistics system in steel-making processis valid and can be used for simulating logisticsin upcoming 100% continuous casting process of PISCO. The better schedule scheme of production and reasonable match of converter-caster in time and capacity can be achieved with the help of using simulation approach.     

Nonlinear Characteristic Modeling of Servo Value on Hydraulic Bending Roll System''s Dynamic Characteristic

Nonlinear characteristic of servo value is the important factor influencing hydraulic system, the model of electro-hydraulic servo pressure control system is designed. In this model, flux-equation of servo valve is specially applied and some non-linear characteristics are considered. Furthermore, SIMULINK toolbox of MATLAB language software is applied to solve mathematic model and simulation curves of some variables are obtained. The calculation results are in good agreement with the experimental results.     

Micromodel of Computer Emulational Simulation on Twin-roll Casting Strip Solidification Structure

Based on the research on the solidifiation of twin-roll casting strip,the analytical model and emulational model of nucleation,the growth of dendrity tip and colunar dendrity transformation to equiaxis dendrity (CET)of twin-roll casting strip solidification are established by means of the principle of metal solidification and modern computer emulational technology.The foundation for the emulational simulation of twin-roll casting strip solidification structure is laid.     

The Staged Simulation Method for Power Electronics Circuits

This paper in troduces a staged simulation method fur power electronics circuits,presents an exampleued the method for the CSI/IM drive system.     

Physical simulation of fluid field and structure optimization in two-strand tundish

The influence of the structure and location of dam and weir on fluid flow state in a two-strand tundish is studied, and a set of optimal structure, combining with the average residence time calculated from RTD curve, is obtained. The result indicates that the fluid flow state can be changed and the path of the fluid flow can be prolonged as well as the average residence time is improved after using dam and weir. But there are some dead zones after fluid passed through the dam and weir. Combination scheme of No. one dam and weir is better than the others. Its average residence time is 299 s and the volume fraction of dead zone is 31.0%. After the optimization of flowing control parameters in tundish, the best case is that the distance between dam and weir is 290 mm and the distance between weir and the long nozzle is 383 mm. The longest average residence time is 351 s and the minimum volume fraction of dead zone is 19.0% under the above situation. Compared with that of no dam and weir, the average residence time increases by 65 s and the dead zone volume fraction decreases by 15.0%. Based on Newton formula, the calculated results show that the inclusions with diameter larger than 17.5 μm can float up within 351 s under this optimization situation.