8~#风机排气消声器的设计与应用

本文提出了大截面消声器的设计方法和步聚,并对大型消声器的制造技术及其应用效果进行了探讨.     

活塞环表面碳化铌镀覆新工艺试验研究

用化学液相沉积方法，在高强度灰铸铁活塞环表面实现了Ｎｂｃ覆层，盘销磨擦磨损试验表明，无论在无润滑的情况时，Ｎｂｃ镀层表面要比镀Ｃｒ表面或铸铁原始表面具有更高的耐磨性，可以延长活塞环使用寿命，而Ｎｂｃ镀层与铸铁之间低的磨擦系数可使Ｓ１９５柴油机磨擦损失降低０．３５ｋＷ，降低比油耗９－５ｇ／（ｋＷ．ｈ）。     

Theoretical design for a class of chaotic stream cipher based on nonlinear coupled feedback

1.INTRODUCTION Inordertoimprovethesecurityofchaosencryption system,wecaniteratethechaossystem.Themore chaossystemiterates,themorecomplexitbecomes, andthemoresecurethecorrespondingchaosencryp tionsystembecomes.Zhouetal[1]proposedaclassof chaoticsequencegeneratorinwhichthelinearseg mentnumberincreasedwiththeiterationnumberex ponentially.Withtheincreaseoftheiterationnum ber,thesecurityofthesystemincreaseswhilethe rateofencoding/decodingdecreases.Inaddition,the phase spacegraphhassomedefe…     

优化铅酸蓄电池化成工艺参数的研究

本文针对生极板为同一型号的电池，采用二次加酸化成，改变电流密度和时间．控制电解液的温度等方法．得到优化的工艺参数。采用该组工艺参数，不仅缩短铅酸蓄电池化成周期．提高生产效率，而且节约能源。     

浅谈广告的创意

介绍了广告创意的内涵、金字塔原理、过程及其思考方法,途述了广告创意的U SP广告策略、品牌形象策略和广告定位策略。     

我国林科类高等教育发展重心的思考

本文说明了林业高等教育由学术型向应用型转变的重要性,探讨正确把握人才培养类型、培养模式、优化课程体系、改进教学方法等问题。     

化工职业技术教育的现状及其发展对策研究

该文分析了我国化工职业技术教育的现状及特点，从多个角度并以详细的数据材料阐述了现阶段制约我国化工职业技术教育发展的因素，并结合化工职业技术教育的发展趋势讨论对策，总结出化工职业技术教育在今后的发展的道路上应注意的几点事项。     

Iterative Method for Constructing Complete Complementary Sequences with Lengths of 2^mN

Complete complementary sequences are widely used in spectrum spread communications because of their ideal correlation functions. A previous method generates complete complementary sequences with lengths of N^nN （n,N ∈ Z^＋）. This paper presents a new iterative method to construct complete complementary sequences with lengths of 2^mN （m,N ∈ Z^＋）. The analysis proves that this method can produce many sequence sets that do not appear in sequence sets generated by the former method, especially shorter sequence sets. The result will certainly increase the application of complete complementary sequences in communication engineering and related fields.     

Mathematical model of the identical slope surface

The formation of the identical slope surface and the method of construction are discussed. On the basement of building the parameter equation of variable-radius circle family envelope, the frequently used parameter equation of the identical slope surface of the top of taper moving along column helix, horizental arc and line is built. The equation can be used to construct the identical slope surface’s contours, gradient lines and three dimensional figures correctly. Biography: Hu Jian-guo(1953-), male, Professor, research direction: CG and CAD.     

Finding global minima with a new dynamical evolutionary algorithm

A new dynamical evolutionary algorithm (DEA) based on the theory of statistical mechanics is presented. This algorithm is very different from the traditional evolutionary algorithm and the two novel features are the unique of selecting strategy and the determination of individuals that are selected to crossover and mutate. We use DEA to solve a lot of global optimization problems that are nonlinear, multimodal and multidimensional and obtain satisfactory results. Foundation item: Supported by the National Natural Science Foundation of China (No. 60133010, NO. 60073043 and No. 700/1042) Biography: Zou Xiu-fen(1996-), female, Ph. D candidate, Associate professor, research direction: evolutionary computing, parallel computing.