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21.
针对深层水域水下机器人通过机械臂捕捉目标物定位精度低、搜索难度大、耗费时间长的问题,提出一种基于多策略改进型麻雀搜索算法的水下机器人伸缩臂轨迹定位方法。通过D-H参数法搭建伸缩臂模型,结合MATLAB和ADAMS分析伸缩臂在水下捕捉目标物群目标物的低效性,引用麻雀搜索算法中鸟群觅食在最优位置的思想,引入Logistic混沌映射和柯西高斯变异原理,通过水下机器人的4项性能指标分析最优结果。结果表明:优化后的麻雀算法优于其他算法,同粒子群算法、天牛群算法、鲸鱼优化算法相比,伸缩臂捕捉目标物轨迹路线更加精确,水域环境下避障更为明显。 相似文献
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Dragos Horvath Michael Lisurek Bernd Rupp Ronald Kühne Edgar Specker Jens von Kries Didier Rognan C. David Andersson Fredrik Almqvist Mikael Elofsson Per‐Anders Enqvist Anna‐Lena Gustavsson Nikita Remez Jordi Mestres Gilles Marcou Alexander Varnek Marcel Hibert Jordi Quintana Ronald Frank 《ChemMedChem》2014,9(10):2309-2326
This work describes a collaborative effort to define and apply a protocol for the rational selection of a general‐purpose screening library, to be used by the screening platforms affiliated with the EU‐OPENSCREEN initiative. It is designed as a standard source of compounds for primary screening against novel biological targets, at the request of research partners. Given the general nature of the potential applications of this compound collection, the focus of the selection strategy lies on ensuring chemical stability, absence of reactive compounds, screening‐compliant physicochemical properties, loose compliance to drug‐likeness criteria (as drug design is a major, but not exclusive application), and maximal diversity/coverage of chemical space, aimed at providing hits for a wide spectrum of drugable targets. Finally, practical availability/cost issues cannot be avoided. The main goal of this publication is to inform potential future users of this library about its conception, sources, and characteristics. The outline of the selection procedure, notably of the filtering rules designed by a large committee of European medicinal chemists and chemoinformaticians, may be of general methodological interest for the screening/medicinal chemistry community. The selection task of 200K molecules out of a pre‐filtered set of 1.4M candidates was shared by five independent European research groups, each picking a subset of 40K compounds according to their own in‐house methodology and expertise. An in‐depth analysis of chemical space coverage of the library serves not only to characterize the collection, but also to compare the various chemoinformatics‐driven selection procedures of maximal diversity sets. Compound selections contributed by various participating groups were mapped onto general‐purpose self‐organizing maps (SOMs) built on the basis of marketed drugs and bioactive reference molecules. In this way, the occupancy of chemical space by the EU‐OPENSCREEN library could be directly compared with distributions of known bioactives of various classes. This mapping highlights the relevance of the selection and shows how the consensus reached by merging the five different 40K selections contributes to achieve this relevance. The approach also allows one to readily identify subsets of target‐ or target‐class‐oriented compounds from the EU‐OPENSCREEN library to suit the needs of the diverse range of potential users. The final EU‐OPENSCREEN library, assembled by merging five independent selections of 40K compounds from various expert groups, represents an excellent example of a Europe‐wide collaborative effort toward the common objective of building best‐in‐class European open screening platforms. 相似文献
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介绍了数字测图的产生背景,并对测量方法与手段的发展历程进行了阐述,分析了大比例尺数字测图系统的发展与简化,最后对大比例尺数字测图的发展趋势进行了展望,以减轻工作人员的工作强度,同时提高了测图的精度。 相似文献
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以山东淄博某烟囱项目为例,运用映射变换法计算出在安全系数K=2时,工程实践中可能出现的活荷载、恒荷载标准值比值ID下的单桩可靠度指标β,并给出了ρ,β关系函数,检验了在何种情况下能达到所规定的目标可靠度。 相似文献
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Divya P. Tolia-Kelly 《Landscape Research》2004,29(3):277-292
In this paper the migration routes of British Asian women living in London are examined. It is shown that British Asians connect with a myriad of landscapes abroad, including East Africa, India and Pakistan. These connections to past landscapes are mapped and considered here as valued environments of British Asian women in Britain. Through the mapping of their biographies, it is apparent that memories of other landscapes are embedded in environmental practices in Britain, therefore contributing to making the landscape in Britain inclusive and meaningful in the context of the South Asian migration. The maps of migration show the heterogeneity of landscapes experienced by the British Asian women. Memories of other lands manifest themselves in the UK. The effect of these memories on the South Asian home itself in the process of shaping diasporic geographies of belonging and being within the UK is illustrated. 相似文献
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