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1.
Object detection performed by Autonomous Vehicles (AV)s is a crucial operation that comes ahead of various autonomous driving tasks, such as object tracking, trajectories estimation, and collision avoidance. Dynamic road elements (pedestrians, cyclists, vehicles) impose a greater challenge due to their continuously changing location and behaviour. This paper presents a comprehensive review of the state-of-the-art object detection technologies focusing on both the sensory systems and algorithms used. It begins with a brief introduction on the autonomous driving operations and challenges. Then, different sensory systems employed on existing AVs are elaborated while illustrating their advantages, limitations and applications. Also, sensory systems employed by different research are reviewed. Moreover, due to the significant role Deep Neural Networks (DNN)s are playing in object detection tasks, different DNN-based networks are also highlighted. Afterwards, previous research on dynamic objects detection performed by AVs are reviewed in tabular forms. Finally, a conclusion summarizes the outcomes of the review and suggests future work towards the development of vehicles with higher automation levels. 相似文献
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国家公园以资源保护为前提,其理念已在全世界范围获得共识,不同国家、不同地域环境造就了不同的国家公园体制的形成。以肯尼亚国家公园为例,沿着国家公园建立发展的时间轨迹,介绍了肯尼亚国家公园建设的发展历程,对其在野生动物保护、管理体制、生态旅游发展方面的特色和经验作了探讨。 相似文献
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Primary Li-air cell development 总被引:1,自引:0,他引:1
Owen Crowther Benjamin MeyerMichael Morgan Mark Salomon 《Journal of power sources》2011,196(3):1498-1502
In the present communication, we report on recent researches for optimizing the performance of a primary organic-based Li-air cell. These researches focus on new processing technologies for a high capacity and high rate capable carbon cathode, and the development of oxygen selective membranes based on polysiloxane and methacrylate-polysiloxane copolymers. These membranes, generally classified as silicone rubbers exhibit high permeability for oxygen and impede water transport from the atmosphere into the Li-air cell and solvent loss from the cell into the atmosphere. 相似文献
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This special issue is the result of sustained and highly collaborative efforts to improve the use of remotely sensed data to inform management of protected areas. The 15 papers in the issue address a diverse range of topics. These papers provide a conceptual basis and a framework for establishing monitoring programs, techniques and methods to make operational the use of remotely sensed data, case studies, and synthesis papers liking remotely sensed data to models used to inform ecological assessments. Studies in this issue necessarily confront the universal challenges of scale, both spatial and temporal, and the sometimes tenuous link between observed patterns and significant ecological process. A clear message is that the information needs of resource managers require information across scales, and these information demands will continue to motivate advances in the collection and analysis of remotely sensed data. This compilation of papers is unusual in (1) articulating a basic, if somewhat technical, foundation of remote sensing that is required for resource managers to effectively collaborate with remote sensing specialists, and (2) providing a framework for addressing monitoring resource issues that is likely to be of interest to many remote sensing specialists. We hope these papers inspire broader use of remotely sensed data to manage the increasingly rare and valuable resources in protected areas around the world. 相似文献
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从整体上介绍了LOD DB和ADO的组成结构以及相互关系,提供了使用它们编写数据访问时应用程序的编写模型。 相似文献
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Multi-tenure reserve networks aim to connect areas managed for biodiversity conservation across public and private land. This paper seeks to determine to what extent multi-tenure reserve networks improve the reserve design and connectivity of the public protected area estate, using three networks in southeastern Australia as case studies. Network configuration varied considerably and those networks with generally larger parcels tended to be better connected. On average, public land components were larger than private land components in all networks. Two networks had 18 components physically adjoining other network components while another had only 6 components adjoining. Importantly for two of the networks, the average distance between the nearest neighbouring component was significantly less than average distances between public protected areas in the subregion. Thus these multi-tenure reserve networks acted to enhance the existing public protected area estate by increasing the potential linkages in the landscape and therefore the viability of individual public protected areas. 相似文献
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Alfaia CM Castro ML Martins SI Portugal AP Alves SP Fontes CM Bessa RJ Prates JA 《Meat science》2007,75(1):44-52
This paper describes the influence of slaughter season on lipid content, fatty acid composition, conjugated linoleic acid (CLA) isomeric profile and nutritional value of fat in Barrosã veal from calves reared according to the specifications of the Protected Designation of Origin (PDO). Barrosã purebred calves (n = 27) were raised in a traditional production system and slaughtered in early autumn (October) and late spring (June). Barrosã-PDO veal only presented seasonal differences in the levels of some minor fatty acids and CLA isomers, as well as in the PUFA/SFA ratio. Based on the analysed grass intake indicators, it was shown that veal-PDO has similar values to pasture-fed cattle for both slaughter seasons. From a human nutrition perspective, intramuscular fat in Barrosã-PDO veal has a high nutritional value throughout the year, since CLA contents and the percentages of the c9,t11 isomer are relatively high, and the n − 6/n − 3 ratios are within the recommended values for the human diet. 相似文献