Shorted Microstrip Patch Antenna Using Inductively Coupled Feed for UHF RFID Tag

A very small patch‐type RFID tag antenna (UHF band) using ceramic material mountable on metallic surfaces is presented. The size of the proposed tag is 25 mm×25 mm×3 mm. The impedance of the antenna can be easily matched to the tag chip impedance by adjusting the size of the shorting plate of the patch and the size of the feeding loop. The measured maximum reading distance of the tag at 910 MHz was 5 m when it was mounted on a 400 mm × 400 mm metallic surface. The proposed design is verified by simulation and measurements which show good agreement.     

Domestic Micro-Environments

In the following works, Mathieu Lehanneur readdresses our understanding of domestic spaces through the environmental systems that control and condition them. Such spaces are generally conditioned by centralised heating, cooling and ventilation systems that lump together many sensory qualities, including primary thermal controls as well as by-products of scent and sound, into a singular, mechanical system that fails to engage any of them fully. Lehanneur's projects look to separate these senses into systems distributed throughout the home, engaging each one specifically and locally, in an attempt to redefine the domestic spaces they are located within. Copyright © 2009 John Wiley & Sons, Ltd.     

淹没植被群周围泥沙冲淤特性研究

受自然条件影响和上下游来输沙限制,河道中被淹没植被群周围床面一般呈两侧冲刷、尾部淤积的状态。通过水槽试验模拟分析了河道中植被群周围地形变化特征,研究了不同淹没度下植被群周围泥沙冲淤机理。结果表明,植被群高度不影响其内部与两侧侵蚀变化过程,但较高植被群加速了冲刷速率,促使两侧侵蚀区域向植被群后方延伸;同时在上游无来沙条件下,植被群高度的增大有效抑制了尾流区泥沙沉积。     

三次平面H-Bézier 螺线

基于光顺曲线设计需求,一条曲率单调且曲率正负不变的三次平面 H-Bézier 螺线段被构造。由于此螺线具有起点曲率为零的特性,它可以替代回旋曲线作为道 路设计中的缓和曲线。同时螺线还含有形状参数,故它具有曲线形状可调性的优点。最后, 利用此H-Bézier 螺线,构造了两直线间满足G2 连续的缓和曲线。     

一种基于单调多边形的三角剖分算法

提出了一种基于单调多边形三角化算法,被三角化的多边形可以含有任意 个内孔。先根据边界y(x)方向的局部极值顶点作水平（垂直）分割线,将多边形划分成单连 通y(x)单调多边形,然后再将各单调多边形三角化。算法考虑了各种几何奇异情况,因此比 较稳定。     

基于非局部的图像去噪方法的发展现状综述

通过对图像的相似块做处理从而达到去噪目的,是当前较为新颖的去噪方法,在对国内外利用相似块去噪文献进行理解和分析的基础上,回顾相似块去噪研究的发展,阐明相似块去噪的原理,并总结了相似块去噪的各种方法。最终基于对相似块去噪方法的分析,提出了对其研究方法的展望。     

一种微带贴片天线RCS减缩新方法

为了减小微带贴片天线的雷达散射截面(RCS),利用电磁带隙结构(UC-EBG)的带阻特性,提出用UC-EBG代替普通金属作为微带贴片天线的地板．当天线工作频带内的电磁波入射时,UC-EBG地板呈现出带阻特性,不影响天线的正常工作;而在该频带以外,UC-EBG地板具有良好的带通特性,对入射电磁波起透射作用,从而可以达到减小天线带外RCS的目的．仿真和测量的结果吻合良好,证明了此方法的有效性．     

银杏叶提取物对豚鼠心室肌细胞动作电位及L 型钙离子通道的影响

目的:观察银杏叶提取物(EGB)对豚鼠心室肌细胞动作电位和L-型钙通道的影响。方法:采用全细胞膜片钳技术的电流钳记录动作电位和电压钳记录L-型钙离子通道电流(I_Ca-L)。结果:银杏叶提取物(原液含银杏黄酮甙0.804 g·L^-1, 银杏内酯0.06 g·L^-1)明显缩短心室肌细胞动作电位时程(APD), 1 ∶800 稀释液致APD₉₀ 缩短13 %(P <0.05), 1 ∶200 稀释液致APD₉₀缩短23 %(P <0.05);银杏叶提取物对心肌细胞L-型钙离子通道的开放有抑制作用, 在1 ∶800 时I_Ca-L 峰值降低15 %(P <0.05), 1 ∶200 时I_Ca-L 峰值降低42 %(P <0.05), 均呈浓度依赖性, 随着药物浓度的增加, I-V 关系曲线逐渐上移, 但出现电流峰值的电压不变。结论:银杏叶提取物能明显缩短APD, 抑制心肌细胞钙离子通道的开放, 具有明显的浓度依赖关系, 可能是其抗心律失常的分子基础。     

炭纤维/ 环氧复合材料单面修补中心裂纹铝合金板的静态和疲劳特性

利用真空袋压工艺, 采用单向炭纤维复合材料补片对中心裂纹铝合金板进行了单面胶接修补。测试了复合材料修补板的静态拉伸强度及修补板在拉拉疲劳过程中的裂纹扩展、界面脱粘和剩余拉伸强度等疲劳性能。结果表明, 复合材料补片胶接修补能有效地提高裂纹板的破坏强度和刚度, 降低裂纹板的疲劳裂纹扩展速率, 提高其疲劳寿命。裂纹板经单向炭纤维/ 环氧复合材料补片修补后, 其破坏强度从311. 48 MPa 提高到364. 74 MPa ,疲劳寿命从32217 次提高到77546 次。疲劳导致修补结构的粘接界面脱粘, 脱粘区域近似椭圆形; 脱粘面积随疲劳周次的增加而增加, 且增加的幅度与疲劳周次相关。      

Monotonicity in chemical reaction systems

This article discusses the question of when the dynamical systems arising from chemical reaction networks are monotone, preserving an order induced by some proper cone. The reaction systems studied are defined by the reaction network structure while the kinetics is only constrained very weakly. Necessary and sufficient conditions on cones preserved by these systems are presented. Linear coordinate changes which make a given reaction system cooperative are characterized. Also discussed is when a reaction system restricted to an invariant subspace is cone preserving, even when the system fails to be cone preserving on the whole of phase space. Many of the proofs allow explicit construction of preserved cones. Numerous examples of chemical reaction systems are presented to illustrate the results.