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91.
曾智焕 《重庆科技学院学报(社会科学版)》2010,(16)
针对目前国内一些美术院校开设的设计教学课程的定位问题,结合教学实践,探讨学生创造性思维的培养,认为课程配置与合理定位是适应艺术设计人才培养的关键. 相似文献
92.
该文从空间入手,以杭州城西水街为例,研究了水与城市有机结合的方法和必要性,阐明其中所蕴含的文化沉积和历史底蕴是值得我们去感悟的。 相似文献
93.
介绍了广州亚运会游泳跳水馆防水材料设计选用的原则,即应根据防水工程具体特点有针对性地选择适合的防水材料;分析了东方雨虹JSA-101 Ⅱ型聚合物水泥防水涂料在该工程中的应用优势. 相似文献
94.
文章在分析建筑工程民用电电能损耗原因的基础上,提出供配电系统、电机的节能、照明系统等五项降耗节能的措施。 相似文献
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This paper presents a new type of filtered backprojection (FBP) algorithm for fan-beam full- and partial-scans. The filtering is shift-invariant with respect to the angular variable. The backprojection does not include position-dependent weights through the Hilbert transform and the one-dimensional transformation between the fan- and parallel-beam coordinates. The strong symmetry of the filtered projections directly leads to an exact reconstruction for partial data. The use of the Hilbert transform avoids the approximation introduced by the nonuniform cutoff frequency required in the ramp filter-based FBP algorithm. Variance analysis indicates that the algorithm might lead to a better uniformity of resolution and noise in the reconstructed image. Numerical simulations are provided to evaluate the algorithm with noise-free and noisy projections. Our simulation results indicate that the algorithm does have better stability over the ramp-filter-based FBP and circular harmonic reconstruction algorithms. This may help improve the image quality for in place computed tomography scanners with single-row detectors. 相似文献
98.
Cell Membrane Camouflaged Hollow Prussian Blue Nanoparticles for Synergistic Photothermal‐/Chemotherapy of Cancer 下载免费PDF全文
Wansong Chen Ke Zeng Hong Liu Jiang Ouyang Liqiang Wang Ying Liu Hao Wang Liu Deng You‐Nian Liu 《Advanced functional materials》2017,27(11)
Nanodrug‐based cancer therapy has been actively developed in the past decades. The main challenges faced by nanodrugs include poor drug loading capacity, rapid clearance from blood circulation, and low antitumor efficiency with high risk of recurrence. In this work, red blood cell (RBC) membrane camouflaged hollow mesoporous Prussian blue nanoparticles (HMPB@RBC NPs) are fabricated for combination therapy of cancer. The stability, immune evading capacity, and blood retention time of HMPB@RBC NPs are significantly enhanced compared with those of bare HMPB NPs. Doxorubicin (DOX), as a model drug is encapsulated within HMPB@RBC NPs with loading capacity up to 130% in weight. In addition, DOX loaded HMPB@RBC NPs show pH‐/photoresponsive release. The in vivo studies demonstrate the outstanding performance of DOX@HMPB@RBC NPs in synergistic photothermal‐/chemotherapy of cancer. 相似文献
99.
On energy efficiency of geographic opportunistic routing in lossy multihop wireless networks 总被引:1,自引:0,他引:1
Geographic opportunistic routing (GOR) is an emerging technique that can improve energy efficiency in lossy multihop wireless networks. GOR makes local routing decision by using nodes?? location information, and exploits the broadcast nature and spatial diversity of the wireless medium to improve the packet forwarding reliability. In this paper, our goal is to fully understand the principles and tradeoffs in GOR, thus provide insightful analysis and guidance to the design of more efficient routing protocols in multihop wireless networks. We propose a local metric, one-hop energy efficiency (OEE), to balance the packet advancement, reliability and energy consumption in GOR. We identify and prove important properties about GOR on selecting and prioritizing the forwarding candidates in order to maximize the expected packet advancement. Leveraging the proved properties, we then propose two localized candidate selection algorithms with O(N 3) running time to determine the forwarding candidate set that maximizes OEE, where N is the number of available next-hop neighbors. Through extensive simulations, we show that GOR applying OEE achieves better energy efficiency than the existing geographic routing and blind opportunistic routing schemes under different node densities and packet sizes. 相似文献
100.