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41.
In an environment where robots coexist with humans, mobile robots should be human-aware and comply with humans' behavioural norms so as to not disturb humans' personal space and activities. In this work, we propose an inverse reinforcement learning-based time-dependent A* planner for human-aware robot navigation with local vision. In this method, the planning process of time-dependent A* is regarded as a Markov decision process and the cost function of the time-dependent A* is learned using the inverse reinforcement learning via capturing humans' demonstration trajectories. With this method, a robot can plan a path that complies with humans' behaviour patterns and the robot's kinematics. When constructing feature vectors of the cost function, considering the local vision characteristics, we propose a visual coverage feature for enabling robots to learn from how humans move in a limited visual field. The effectiveness of the proposed method has been validated by experiments in real-world scenarios: using this approach robots can effectively mimic human motion patterns when avoiding pedestrians; furthermore, in a limited visual field, robots can learn to choose a path that enables them to have the larger visual coverage which shows a better navigation performance.  相似文献   
42.
在课程群的教学中由于每门课程各自独立开展教学,缺乏知识的融合和衔接,导致学生运用综合知识解决问题的能力较弱。在课程群的教学中采用案例嵌入协同教学模式,将完整的工程案例嵌入到课程群各门课程的教学中,协同规划各门课程的教学任务,每门课程再围绕案例展开研究性教学。通过嵌入的工程案例衔接各门课程的知识点,帮助学生建构完整的知识体系,强化工程应用的概念;同时通过研究性教学,培养学生分析问题和解决问题的能力,两部分相结合,提高了学生运用综合知识解决复杂问题的能力。  相似文献   
43.
王传旭  薛豪 《电子学报》2020,48(8):1465-1471
提出一种以"关键人物"为核心,使用门控融合单元(GFU,Gated Fusion Unit)进行特征融合的组群行为识别框架,旨在解决两个问题:①组群行为信息冗余,重点关注关键人物行为特征,忽略无关人员对组群行为的影响;②组群内部交互行为复杂,使用GFU有效融合以关键人物为核心的交互特征,再通过LSTM时序建模成为表征能力更强的组群特征.最终,通过softmax分类器进行组群行为类别分类.该算法在排球数据集上取得了86.7%的平均识别率.  相似文献   
44.
In recent years, there has been rapid expansion of glycan synthesis, fueled by the recognition that the structural complexity of sugars translates to a myriad of biological functions. Such chemical syntheses involve many challenges, mostly due to the regio- and stereochemical aspects of glycosidic bond formation. One-pot strategies were developed to assist in attaining faster and more economical access to the glycan constructs. In this front, achievements in protecting group manipulation, glycosylation, and combinations of these have been reported. Protecting group manipulations in one pot take advantage of the reaction compatibility of commonly used transformations, many of which occur in high regioselectivity. Sequential glycosylations, on the other hand, rely on leaving group orthogonalities and reactivity tuning, as well as the preactivation technique. Altogether, these approaches offer attractive means to the much needed glycan structures and, consequently, help usher in advances in glycoscience.  相似文献   
45.
The paper presents an algebraic construction of the basic notions of soft set theory. Here we introduce the definition of bijective soft groups, dependent and independent soft groups. Some of their properties are investigated. Also we investigate the relationships between bijective soft groups and classical groups. In addition, we express some applications of bijective soft groups on coding theory.  相似文献   
46.
粤港澳大湾区世界城市群与世界机场群相伴而生、联动发展.建设世界级机场群,需要5大机场错位发展和良性互动.澳门国际机场是澳门融入粤港澳大湾区重要一极,但机场发展存在与澳门定位、香港珠海空域空运矛盾、澳门土地和环境现状等相关的问题.因此,澳门国际机场今后发展需在葡语国家航线、珠澳密切合作、公务机产业方面努力实现跨越式发展.然而,澳门国际机场改扩建问题争议不断,本文就原址扩建、填海区新建、飞地黄茅岛新建3种模式进行比较分析,探索符合澳门长远利益之方案.  相似文献   
47.
48.
High-speed rail (HSR) has become an essential mode of public transportation in China and is likely to remain so for the foreseeable future. To promote the development of the HSR industry, a high level of passenger satisfaction must be ensured, which means that passenger satisfaction must be assured. Focusing on HSR in-cabin factors that affect the travel experience of HSR passengers, this study aims to determine passenger demands (PDs) and to evaluate passenger satisfaction by using a combination of online review analysis and large-scale group decision-making (LSGDM). By using web crawler technology, online reviews related to HSR were harvested from a microblogging platform to extract PD data and information. The six PDs that reflect the most frequent concerns of passengers were identified by analyzing the online reviews. The level of satisfaction of passengers with respect to these PDs was analyzed based on the online responses from 100 HSR passengers and by adopting the interval-valued two-tuple linguistic representation model. The final degrees of satisfaction and rankings of the PDs were then determined by using the LSGDM approach with the k-means clustering method and a consensus-reaching process. This research thus constructs an index system of HSR passenger satisfaction evaluation based on online-review analysis and evaluates the process by using LSGDM approaches. The conclusions provide insights into the improvements desired by HSR passengers for in-cabin services and to improve passenger satisfaction.  相似文献   
49.
Vineyards are an intensive cultivation system and expose the soil to long-lasting stress. Many vineyard areas already show high degrees of soil degradation. To prevent further soil erosion, cover crops, which have various positive effects on the environment, are highly recommended. But, depending on the climatic conditions, cover crops can reduce grape yields and are sometimes more work intensive than bare soil management. In some areas cover crops are already widespread while in others bare soil is dominant. In this qualitative study, we explore the attitudes of European winegrowers towards cover crops and determine the background for differences in the adoption of greened vineyards. Thus, we conducted focus groups with winegrowers in two different regions, namely Coteaux du Layon in France and Montilla-Moriles in Spain. In this setting, the transregional differences are mainly based on the climatic conditions but also on different business structures and knowledge levels. Direct sellers seem to be more attentive to the environment and use cover crops more often than farmers which sell their grapes to cooperatives.  相似文献   
50.
董艳林  刘懿韬 《计算机仿真》2020,37(4):215-218,249
针对当前空间规划方法存在的计算时间长、规划成本高等问题,提出一种基于蚁群算法的低碳群体建筑外部边缘空间规划方法。依据城市低碳群体建筑外部边缘空间的模糊特性,引入模糊集合理论对建筑外部边缘空间进行理解和建筑外部边缘空间模糊矩阵的构建,对边缘空间进行划分和限定。结合建筑外部边缘空间的特性和具体关系模式进行空间层次划分,计算空间属性权重,以此确立空间规划目标,根据空间规划目标函数构建空间规划模型,设定求解空间规划模型的蚁群算法信息素更新方式,依据个体信息素转移概率指导个体进行模型最优解搜索。实验结果表明,所提方法与传统的空间规划方法相比,有效减少了计算时间,降低了规划成本。  相似文献   
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