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941.
在对图像增强的现状以及小波图像增强总体概括的基础上,介绍了多尺度几何分析的产生和发展,分析了多尺度几何分析在图像增强中的应用,阐述了几种具有代表性的自适应和非自适应多尺度几何分析图像增强方法,对存在的问题和进一步的研究方向做出总结和展望。 相似文献
942.
聚合物共面波导行波电极电光调制器 总被引:1,自引:1,他引:1
用聚合物材料BPAN-NT设计并初步成功制作了共面波导(CPW)行波电极电光调制器。用反应离子刻蚀(RIE)的方法制作脊波导,通过电晕极化使芯层有电光效应,利用电镀方法制作厚行波电极。对调制器的各项特性参数进行了测试,测得调制器的微波损耗系数0α=0.9 dB/cm.(GHz)1/2、在1.317μm波长上Vπ=250 V,由此算得芯层材料的电光系数3γ3=3.7 pm/V,同时测得消光比为13.49dB、插入损耗为18.6 dB,在8 GHz的微波频率上观察到了调制光信号,理论计算3 dB光调制带宽为43.77 GHz。 相似文献
943.
采用国产大功率光纤束模块,双端面泵浦两块Nd∶YVO4 激光晶体,采用高衍射效率声光调Q技术,在注入总功率50W,最高重频100kHz的条件下,获得平均输出功率为18. 21W的1064nm激光输出。脉冲宽度为62ns,相应光光转换效率为36. 4%。在最低重频10kHz时,具有最大单脉冲能量1. 3mJ ,相应脉冲宽度为16. 4ns,峰值功率达到了80kW。 相似文献
944.
目的:探讨He—Ne激光照射对胃癌SGC7901细胞生长的影响。方法:将肿瘤细胞用含10%牛血清RPMI1640培养液培养,并用波长为632.8nm和功率密度为78mw/cm^2的He-Ne激光分别以23J/cm^2,46J/cm^2,72J/cm^2,140J/cm^2,280J/cm^2能量密度照射肿瘤细胞1次或3次,然后用激光共聚焦显微镜检测细胞形态等和四氮唑盐法(MTT)进行活细胞记数。结果:激光照射对肿瘤细胞的形态没有明显影响。这当照射1次时,各种能量密度的激光照射都促进肿瘤细胞的生长。当照射3次时。能量密度小于72J/cm^2时激光照射促进肿瘤细胞的生长,而当能量密度大干72J/cm^2时,反而抑制肿瘤细胞的生长。不管照射1次还是3次23J/cm^2能量密度的激光照射对肿瘤细胞生长的促进作用最明显。结论:He—Ne激光照射对肿瘤细胞生长起促进作用还是抑制作用与激光的累积照射剂量有关。 相似文献
945.
西安凯莱大酒店中央空调施工中的质量控制 总被引:1,自引:0,他引:1
结合西安凯莱大酒店中央空调的施工,概括介绍了工程质量管理的重要性,施工项目质量控制的一些基本概念和具体措施。 相似文献
946.
本文详细介绍了西门子SIMOTION D在高速纸箱包装机上的应用。SIMOTION作为西门子新。代运动控制器增加了很多实用的功能,降低了使用者的编程难度,在一些控制要求较高的机械上可以真正体现出它的优势。 相似文献
947.
Despite the multiple benefits offered today by connected mobile objects networks (CMONs), some constraints continue to limit their development and to degrade their applications and services’ performance. Given their limited energy, some or many objects may stop functioning which leads to the deterioration of network functionalities such as monitoring, detection and transfer of data. It is in this context that our work is situated, namely the improvement of applications performance and the quality of service (QoS) within CMONs, by exploiting some communication environment parameters and geometry techniques. We propose a new technique called self-organization area coverage (SOAC) for CMONs which aims to ensure maximum coverage in the network while optimizing the exploited resources. SOAC has been evaluated and compared not only to the network without improvement but to two other solutions proposed in the literature. The obtained results show a clear improvement in terms of network coverage and several QoS parameters. 相似文献
948.
949.
Xiang Lin Jinglin Wang Xiangyi Wu Yuan Luo Yongan Wang Yuanjin Zhao 《Advanced functional materials》2023,33(6):2211323
Marine organisms provide novel and broad sources for the preparations and applications of biomaterials. Since the urgent requirement of bio-hydrogels to mimic tissue extracellular matrix (ECM), the natural biomacromolecule hydrogels derived from marine sources have received increasing attention. Benefiting from their outstanding bioactivity and biocompatibility, many attempts have been made to reconstruct ECM components by applying marine-derived natural hydrogels. Moreover, marine hydrogels have been successfully applied in biomedicine by means of microfluidics, electrospray, and bioprinting. In this review, the classification and characteristics of marine-derived hydrogels are summarized. In particular, their role in the development of biomaterials is also introduced. Then, the recent advances in bio-fabrication strategies for various hydrogel materials are focused upon. Besides, the influences of hydrogel types on their functions in biomedical applications are discussed in depth. Finally, critical reflections on the limitations and future development of marine-derived hydrogels are presented. 相似文献
950.
Xiong Luo Lei Zhang Yiping Luo Zhuyun Cai Hua Zeng Tianlong Wang Zhiqing Liu Yixing Chen Xuexin Sheng Aquino Ernesto da Graça Mandlate Zifei Zhou Feng Chen Longpo Zheng 《Advanced functional materials》2023,33(26):2214036
The treatment of diabetic wound remains a big clinical challenge. Hydrogel that can provide physical barrier and humidity displays amazing potentials for managing the diabetic wounds healing. Herein, a new charge-driven self-assembled microsphere hydrogel scaffold (SMHS) is reported based on an electric charge interaction, by combining use of black phosphorus (BP)-contained chitosan methacryloyl (CS) microspheres with positive charge and basic fibroblast growth factor-contained hyaluronic acid methacryloyl (HA) microspheres with negative charge. The weak charge attraction among microspheres gives the SMHS the injectable characteristic. Due to the existence of BP, near-infrared (NIR) irradiation has obvious effects on the degradation and drug release behaviors of SMHS. Significantly, SMHS that combines the short-term physical (photothermal) intervention and long-term chemical (drug release) intervention may be promising in spatio-temporal regulation of regenerative microenvironment. SMHS with NIR irradiation (SMHS+NIR) can promote cell proliferation, cell migration, angiogenesis and macrophage polarization. Moreover, in diabetic rat skin wounds, SMHS+NIR significantly accelerates the wound healing process by simultaneously inhibiting the inflammatory response, promoting angiogenesis and tissues remodeling. The outcome of this research not only provides a biomaterial for diabetic wounds healing, but also demonstrates a new strategy for designing novel hydrogel-based biomaterials which have the free editing and combination functions. 相似文献