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61.
相关器的特性变化规律对其实际应用中参数的设定具有重要的指导意义。针对基于比累对切透镜的联合菲涅耳变换相关器,通过数值仿真详细分析了比累对切透镜缝宽变化对相关器输出特性和空变特性的影响。结果表明,比累对切透镜缝宽能一定程度地控制联合菲涅耳变换功率分布的有效面积、相关峰的尖锐度及其空变特性的敏感度。实验采用纯相位空间光调制器编码比累对切透镜相位掩模替代实体透镜的方式搭建了相关器,实验结果与仿真结果一致性好,进一步验证了上述结论的正确性。 相似文献
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陆俊杰 《制冷空调与电力机械》2011,32(6):26-31
分析了暖通设计中如何找到历史保护建筑改建工程“修旧如旧”[1]与“满足建筑使用功能及保证人员舒适度”的最佳平衡点,并结合实际工程介绍了多联空调系统在历史保护建筑中的运用.从“空调系统冷热源的选择”与“空调末端系统的选择”两方面对此进行深入分析,说明了多联空调系统在历史保护建筑改建过程中的优势. 相似文献
64.
GOU Ming-jiang YANG Xi YU Zhi-yuan TAO Ran SHI Qing-fan 《Canadian Metallurgical Quarterly》2011,20(1)
A 48 mm×60 mm×1 mm miniaturized multi-band antenna based on deformed split ring resonators was presented.The antenna was consisted of a micro-strip line and a deformed split square ring.Its/S11/parameters were determined through numerical simulation and experimental measurement within three working bands of 2.6 GHz to 3.0 GHz,3.9 GHz to 4.4 GHz and 5.2 GHz to 5.8 GHz and the results showed that the parameters within all the bands were less than-10 dB.The gain at every frequency for the antenna was above 2.2 dB and it increased monotonously with the frequency from 5.5 GHz to 7.0 GHz. 相似文献
65.
根据Cu-Fe相图,Fe在Cu中溶解度变化和合金成份特点,通过减少热轧道次,来保证合金的固溶效果,同时增加基体中sn含量,提高IC的强度和抗软化能力;采取钟罩炉二次分级时效退火,提高电导率.经过多批次生产实践,材料性能完全满足客户要求. 相似文献
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五阶非线性效应下三阶孤子对演化的数值研究 总被引:1,自引:1,他引:0
对五阶非线性效应下三阶孤子间的相互作用进行了数值研究,结果表明:正五阶非线性作用将会导致三阶孤子对波形进一步恶化。在负五阶非线性作用下,原来的三阶孤子很快发生裂变,三阶孤子对同相位时, 裂变后峰值小的两孤脉冲位于内侧,两个三阶孤子表现出先吸引、碰撞,然后聚合成一个孤脉冲。三阶孤子对反相位时,裂变后峰值强度小的孤脉冲位于外侧,并且一直保持排斥状态,每个三阶孤子裂变数目随负五阶非线性参数绝对值的增大而增多。适当选取负五阶非线性参数值,可以有效地抑制三阶孤子间的相互作用。 相似文献
69.
He-Xiu Xu Guang-Ming Wang Chen-Xin Zhang Qing Peng 《AEUE-International Journal of Electronics and Communications》2011,65(11):901-905
A novel Hilbert-shaped complementary single split ring resonator (H-CSSRR) with an alterative split gap was initially presented and studied. Transmission characteristics of several CSSRR cells were assessed by full-wave electromagnetic (EM) simulation and analyzed by electrical simulation (equivalent circuit model). Miniaturization mechanism as well as effective EM parameters retrieval is also involved. Comparing to conventional CSSRR, proposed H-CSSRR was demonstrated with a merit of lower primary transmission zero realized by negative effective permittivity and multi-resonance behavior attributing to self-similarity of Hilbert geometry. For application, a tunable assembled low-pass filter (LPF) by periodically loading H-CSSRR cells and open stubs is designed, fabricated and measured. Measurement results indicate that the designed LPF has many good performances such as relative low insertion loss (maximum 0.59 dB) in passband, ultra-wide stop-band characterized by 20 dB insertion loss (from 2.45 to 25 GHz) as well as steep rejection with sharp transition band (2.15–2.45 GHz) out of band. Excellent property and consistent numerical and experimental results of the developed LPF have confirmed the effectiveness of this design concept. 相似文献
70.
Yuan Hsing Fu Ai Qun Liu Wei Ming Zhu Xu Ming Zhang Din Ping Tsai Jing Bo Zhang Ting Mei Ji Fang Tao Hong Chen Guo Xin Hai Zhang Jing Hua Teng Nikolay I. Zheludev Guo Qiang Lo Dim Lee Kwong 《Advanced functional materials》2011,21(18):3589-3594
A micromachined reconfigurable metamaterial is presented, whose unit cell consists of a pair of asymmetric split‐ring resonators (ASRRs); one is fixed to the substrate while the other is patterned on a movable frame. The reconfigurable metamaterial and the supporting structures (e.g., microactuators, anchors, supporting frames, etc.) are fabricated on a silicon‐on‐insulator wafer using deep reactive‐ion etching (DRIE). By adjusting the distance between the two ASRRs, the strength of dipole–dipole coupling can be tuned continuously using the micromachined actuators and this enables tailoring of the electromagnetic response. The reconfiguration of unit cells endows the micromachined reconfigurable metamaterials with unique merits such as electromagnetic response under normal incidence and wide tuning of resonant frequency (measured as 31% and 22% for transverse electric polarization and transverse magnetic polarization, respectively). The reconfiguration could also allow switching between the polarization‐dependent and polarization‐independent states. With these features, the micromachined reconfigurable metamaterials may find potential applications in transformation optics devices, sensors, intelligent detectors, tunable frequency‐selective surfaces, and spectral filters. 相似文献