含导数项的p-Laplacian算子多点边值问题三个正解的存在性

利用Leggett-Williams不动点定理的一个扩展定理,研究了非线性项含导数项的pLapla-cian算子多点边值问题,得到了三个正解存在的充分条件.     

Bt防治栗实象甲的试验

Bt(Bacillus thuryingieusis)已成为大规模生产和运用的生物杀虫制剂，通过试验，发现湖北康欣实业有限公司生产的生绿Bt悬浮剂在给定施用范围内稀释800倍杀灭栗实象甲效果最好。     

基于PC/104的某型飞机发射回路信号检测

某型飞机发射回路是武器控制系统的一部分，必须定期对其进行检测为改进原检测设备的技术水平，本文利用PC／104总线技术，设计了飞机发射回路自动测试系统。文中对发射回路信号及检测原理进行了分析，对测试系统的软硬件进行了设计，实际应用表明，该系统具有易于操作，测量迅速准确，可扩展性强等特点。     

基于VRGS的交通流微观仿真软件的开发

基于ＶＲＧＳ的交通流微观仿真软件对交通网络引入ＶＲＧＳ后的交通流进行仿真。本文阐述仿真模型的设计思想,介绍模型的框架结构,说明采用ＶｉｓｕａｌＢａｓｉｃｆｏｒＷｉｎｄｏｗｓ的程序实现方法。     

楼阁世纪现春秋——何镜涵与写意楼阁画

楼阁殿宇作为中国独特的民族建筑形式,在世界建筑史上光彩夺目,是中华民族的骄傲。接阁段宇作为绘画形式出现最早追见于汉代墓壁画。从敦煌璧画上看,北魏时期已有较完整的城郭建筑的描绘了。至北宋时期日臻完善。形成了独立的楼阁殿宇绘画形式——界画,即用界尺画古建筑的我国传统画中的一个分科、也称为台阁画。此后名家倍出,尤其以宋徽宗赵佶为代表的宫廷院体派,所作界画技法高超,多有传世名作。宋末元初随着文人画的兴起,界画渐衰。清代袁江、袁耀父子虽奋力崛起,仍未能挽回颓势,到了近代界画几乎匿迹。楼阁山水画衰落的主要原因是因循守旧,作画必用界尺,枝根末节折算精     

2007年夏平菇市场将更大

预计2007年夏季，平菇市场将依然保持高位运行，排队其他因素的干拢，一般每千克价格将会保持在3元左右，部分地区零售价将突破5元大关，个别地区因总体收入、消费水平制约，可能会低一些，但低于2元的概率很低。     

亚洲企业家:迈向成功的52步

你是否会经常有想自己做生意念头但又不知从何做起?放弃一个稳定而又安全的工作而自谋出路会使人产生一种发自内心的胆怯。“做,还是不做”,这是一个问题。无论作出怎样的选择,生活都将不再相同。 中国有句古话叫做“千里之行始于足下”。勇敢地迈出第一步是战胜胆怯的关键。《亚洲企业家》杂志整理了52项意见,恰好在一年中一     

Adhesion of PBO Fiber in Epoxy Composites

The high mechanical and thermal performance of poly p-phenylene- 2, 6-benzobisoxazole ( PBO ) fiber provides great potential applications as reinforcement fibers for composites. A composite of PBO fiber and epoxy resin has excellent electrical insulation properties, therefore, it is considered to be the best choice for the reinforcement in high magnetic field coils for pulsed magnetic fields up to 100 T.However, poor adhesion between PBO fiber and matrix is found because of the chemically inactive and/or relatively smooth surface of the reinforcement fiber preventing efficient chemical bonding in the interface, which is a challenging issue to improve mechanical properties. Here, we report the surface modification of PBO fibers by ultraviolet (UV)irradiation, O2 and NH3 plasma, as well as acidic treatments. The interfacial adhesion strength values of all the treatments show the similar level as determined for aramid fibers by pull-out tests, a significant impact on fibermatrix-adhesion was not achieved. The surface free energy and roughness are increased for both sized and extracted fibers after plasma treatments together with maleic anhydride grafting. The sized fiber shows marginal improvement in adhesion strength and no change in fiber tensile strength because of the barrier effect of the finish.For the extracted fiber, different surface treatments either show no apparent effect or cause reduction in adhesion strength. Atomic force microscopy (AFM) topography analysis of the fracture surfaces proved adhesive failure at the fiber surface. The fiber surface roughness is increased and more surface flaws are induced, which could result in coarse interface structures when the treated fiber surface has no adequate wetting and functional groups. The adhesion failure is further confirmed by similar adhesion strength and compression shear strength values when the fiber was embedded in various epoxy resins with different temperature behavior. The tensile strength of fiber is sensitive to surface treatment conditions as revealed by a bimodal Weibull statistical distribution analysis. Considerable strength reduction occurred, particularly for cases of acidic and plasma treatments, while UV irradiation shows the better ability to retain fiber strength.     

浅谈自然界能量·转化·守恒·成矿

自然界的形成、发展及其演化源于物质本身具有的能量,源于物质能量的转化和物质能量的守恒.具体而言与天地生的发展演化密切相关,主要是地质作用(包括内力地质作用和外力地质作用)产生的能量(热能、风能、水能)转化、守恒变化的结果.该文从多方面论述了能量、转化、守恒与成矿之间的关系,对地质找矿及其思维有一定的指示意义.     

图像压缩技术的发展

由于数字图像含有大量的数据，为减少存储空间与提高传输速度，采用数据压缩是必需的。按照编码方法是否利用信宿（人的眼睛）特性对它们进行了分类，简要介绍了各种图像压缩技术的理论指导思想与实现方法。