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71.
Sixty sediment samples were collected from the main Songhua River in three years. Twelve polybrominated diphenyl ether ( PBDE) congeners ( BDE17, 28, 47, 66, 99, 100, 153, 154, 138, 183, and BDE?209) w...  相似文献   
72.
Gas migration in coal bed is a multiple-physical process, of which not only includes gas desorption/diffusion through coal matrix and gas Darcy flow through the cleat system, but also results in deform...  相似文献   
73.
Cheng  Jiaqi  Gong  Junyi  Yue  Shuai  Jiang  Yao  Hou  Xiangjun  Ma  Jianjun  Yao  Yali  Jiang  Cairong 《Journal of Applied Electrochemistry》2021,51(8):1175-1188
Journal of Applied Electrochemistry - La-doped titanate materials have been widely investigated as alternative Ni-free anodes for solid oxide fuel cells (SOFCs). In this study, La0.4Sr0.6TiO3 (LST)...  相似文献   
74.
We present a distillation algorithm which operates on a large, unstructured, and noisy collection of internet images returned from an online object query. We introduce the notion of a distilled set, which is a clean, coherent, and structured subset of inlier images. In addition, the object of interest is properly segmented out throughout the distilled set. Our approach is unsupervised, built on a novel clustering scheme, and solves the distillation and object segmentation problems simultaneously. In essence, instead of distilling the collection of images, we distill a collection of loosely cutout foreground “shapes”, which may or may not contain the queried object. Our key observation, which motivated our clustering scheme, is that outlier shapes are expected to be random in nature, whereas, inlier shapes, which do tightly enclose the object of interest, tend to be well supported by similar shapes captured in similar views. We analyze the commonalities among candidate foreground segments, without aiming to analyze their semantics, but simply by clustering similar shapes and considering only the most significant clusters representing non‐trivial shapes. We show that when tuned conservatively, our distillation algorithm is able to extract a near perfect subset of true inliers. Furthermore, we show that our technique scales well in the sense that the precision rate remains high, as the collection grows. We demonstrate the utility of our distillation results with a number of interesting graphics applications.  相似文献   
75.
Li  Fuliang  Gong  Junfeng  Liang  Yunyi  Zhou  Jiali 《Multimedia Tools and Applications》2016,75(24):17573-17592
Multimedia Tools and Applications - Congestion prediction can support traffic departments to take effective traffic management measures, and it aids users to adopt smarter trip strategies,...  相似文献   
76.
Big data technologies and a range of Government open data initiatives provide the basis for discovering new insights into cities; how they are planned, how they managed and the day-to-day challenges they face in health, transport and changing population profiles. The Australian Urban Research Infrastructure Network (AURIN – www.aurin.org.au) project is one example of such a big data initiative that is currently running across Australia. AURIN provides a single gateway providing online (live) programmatic access to over 2000 data sets from over 70 major and typically definitive data-driven organizations across federal and State government, across industry and across academia. However whilst open (public) data is useful to bring data-driven intelligence to cities, more often than not, it is the data that is not-publicly accessible that is essential to understand city challenges and needs. Such sensitive (unit-level) data has unique requirements on access and usage to meet the privacy and confidentiality demands of the associated organizations. In this paper we highlight a novel geo-privacy supporting solution implemented as part of the AURIN project that provides seamless and secure access to individual (unit-level) data from the Department of Health in Victoria. We illustrate this solution across a range of typical city challenges in localized contexts around Melbourne. We show how unit level data can be combined with other data in a privacy-protecting manner. Unlike other secure data access and usage solutions that have been developed/deployed, the AURIN solution allows any researcher to access and use the data in a manner that meets all of the associated privacy and confidentiality concerns, without obliging them to obtain ethical approval or any other hurdles that are normally put in place on access to and use of sensitive data. This provides a paradigm shift in secure access to sensitive data with geospatial content.  相似文献   
77.
提出了一种基于灰关联混合蛙跳算法的雷达波形设计方法,以混合蛙跳算法为主体,在局部更 新算子中引入遗传算法的遗传算子,并改进原始蛙跳算法的分组方法,丰富了种群的多样性,同时引入灰关联综合评价法则对适应度函数值加以关联度分析。文中以设计具有低自相关旁瓣和互相关特性的正交多相编码为例,将该算法用于雷达波形设计中。仿真结果表明使用本文算法产生 的波形具备较好的低自相关特性和互相关特性,表明了该算法是有效和可行的。  相似文献   
78.
针对提升电-机械转换器快速响应特性的技术需求,提出了新型三线圈结构电-机械转换器。通过建立的电-机械转换器数学模型,提出采用细菌觅食算法来寻找时间最优解,并基于此方法设计了砰-砰与比例-积分双模控制器。分析与仿真结果表明,相对于传统单线圈电-机械转换器,采用双模控制器的三线圈电-机械转换器,其响应时间从8.5 ms缩短至2.5 ms,震荡和超调不超过5%,可知该技术能够实现响应特性,前景良好。  相似文献   
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