带吊车门式刚架轻型钢结构厂房的设计与分析

以实际工程为背景，采用门式刚架轻型房屋钢结构设计规程，对带吊车门式刚架、吊车梁、抗风柱及基础的受力特点、设计方法进行分析，解决了设计中所遇到的问题。     

Ornament and function

The architects and builders in the past lacked our knowledge concerning fluid dynamics, but they exhibited a deep rooted ability to observe and reflect - thus, different cultures have developed by trial and error. The authors have produced a stimulating analysis which couples the science of fluid dynamics and a sensitive understanding of past cultures. The paper is recommended reading.     

10000m^3内浮顶油罐双浮动吸油装置设计

介绍了某油库扩建工程中10 000 m3内浮顶油罐双DN500浮动吸油装置的结构设计,并对内浮顶罐浮动吸油装置的浮力进行了优化配置,此经验对我国内浮顶油罐浮动吸油装置的设计和使用具有一定的指导意义.     

ON THE SLOW MANIFOLD CHARACTERISTICS OF CAPILLARY SUCTION APPARATUS DYNAMICS

The nonlinear dynamic behaviour relating the wet front size and liquid saturation under inner cylinder (or rectangular cell) in cylindrical (or rectangular) capillary suction apparatus was investigated. The slow manifold explanation was proposed and the fast- and slow-varying variables were identified. Experiments were conducted to verify theoretical findings.     

风力发电与变流器

讨论了目前流行的两种主流风力发电系统：变速恒频双馈风力发电系统和永磁直驱同步风力发电系统。着重分析了两种风电变流器的拓扑结构、工作原理和性能特点,对风力发电系统发电机、变流器、无功支持和低电压穿越能力等方面进行了论述。     

基于Vega粒子系统的自由大气分子运动虚拟仿真

在军事训练中,三维仿真的战场环境发挥了极为重要的作用。本文将对战场环境中的自由大气进行虚拟仿真。首先分析自由大气中运动分子的性质,详细介绍在模拟不规则自然现象中运用最多的粒子系统技术,最后在Vega中运用粒子系统对大气分子的运动进行模拟仿真。仿真结果能基本模拟出大气分子的运动特性,且可以通过接口编程访问粒子的属性,从而能在无人机等航迹规划的危险天气现象的规避中加以运用。     

环境荷载联合作用下海上风电结构动力响应分析

为研究海上风电结构在复杂的海洋环境中承受环境荷载(风、波、冰、流)的联合作用时,结构产生的剧烈的动力响应问题。文章以三脚架基础海上风电结构为研究对象,采用ANSYS有限元软件建立其整体模型并进行荷载(风、波、流和风、冰、流)联合作用下的静力校核,通过对环境荷载联合作用下的三脚架基础海上风电结构进行瞬态分析,掌握其动力响应的特性及规律。结果表明:三脚架基础结构的一、二阶自振频率均为0.285Hz,在所选风机允许的频率范围内,可以保证整体结构不会与风机转动发生共振;风荷载在风、波、流荷载联合作用下主导控制结构响应的稳态波动,冰荷载在风、冰、流荷载联合作用下主导控制结构的稳态振动过程;塔筒顶端呈现的位移和加速度响应均远大于三脚架基础顶端;环境荷载联合作用下结构动力响应是环境荷载单独作用下动力响应叠加的结果。     

自适应变步长最大风能捕获算法

风能具有随机性、不稳定性的特点,为了提高风力发电系统中风能的利用效率,在比较各种最大风能捕获算法的基础上,分析了爬山搜索法和叶尖速比法的不足,提出了自适应变步长搜索算法来捕获最大风能.通过改进爬山搜索法的变步长策略,明显加快了搜索速度,通过引入初始估计叶尖速比值,大大缩小了搜索范围.该算法不需要实时检测准确风速,不依赖风力机最佳功率曲线,有效地降低了成本,提高风力发电的效率.文中重点分析了算法的自适应性和变步长策略,仿真结果表明,该算法能够使风力机更快速到达最大功率点,动态响应快,收敛性好.     

Behavioral and electrophysiological activity of (Z,E)-7,9,11-dodecatrienyl formate,a mimic of the major sex pheromone component of carob moth,Ectomyelois ceratoniae

The behavioral and electrophysiological activity of a mimic [(Z,E)7,9,11-dodecatrienyl formate] of the major sex pheromone component [(Z,E) 9,11,13-tetradecatrienal] of carob moth was assessed. Wind-tunnel bioassays demonstrated that the formate was as effective as natural gland extracts, and significantly more effective than the trienal alone or than the trienal blended with two minor pheromone components, in evoking source contact. Dispensers containing the formate were as effective as trienal-containing blend lures in attracting males when placed at the same dosage in traps in date gardens. Single-cell recordings showed that at least two olfactory neurons, differentiated by spike amplitude, are located in the long trichoid hairs on male carob moth antennae. Dose-response relationships indicated that puffs from cartridges loaded with at least 0.1 g of the formate or of the trienal were necessary to elicit spiking by either the small or the large-spiking cell within a sensillum. Cross-adaptation studies demonstrated that both compounds stimulated the same large-spiking cell. The frequencies of spikes evoked from the large cell when stimulated by emissions from 0.1-g, 1-g, or 10-g cartridges of either the formate or the trienal were not significantly different, suggesting that the formate is an effective mimic of the trienal at the antennal receptor cell level.     

太阳风粒子数据映射模型的设计与实现

为了能够快速获得第三级太阳风粒子可分析处理的结构化数据,本文采用将数据映射到内存和采用语言集成查询技术解决数据的完整映射和快速访问。通过设计数据映射模型,将用PDS数据的数据标签和数据产品分别映射到模型的值域和属性域,解决本地或网络数据内存映射的问题。为测试这个实例,采用双倍缓冲和贝塞尔插值技术对数据能谱进行了实时绘制。结果表明该模型具有高效性、完备性和高吻合度。这个基于内存映射的模型能够较好地解决异构数据快速结构化数据访问的数据源动力不足问题,为进一步处理和分析太阳高能粒子的频谱、成份和通量及随时间、空间变化的分布特征等提供了基础。