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排序方式: 共有88条查询结果,搜索用时 15 毫秒
81.
2020年全面建成小康社会,“十三五”是关键时期.随着全面小康目标的加速推进,“老少边穷弱”地区扶贫攻坚更加显得意义重大. 基于参与式农村评估和数理统计分析方法,以回族聚居宁夏限制开发生态区30个典型农村社区为研究对象,按居住地形对农村社区的发展能力进行评估,构建多元线性回归模型,揭示影响不同类型社区发展能力的主要因素,结合研究区实际,对区域发展提出建议. 研究发现,山地社区发展能力显著弱于川道社区;不同类型社区,影响其发展能力的因素差异显著;区位因素是决定社区发展能力的关键,包括自然区位和经济区位.本研究可为解决区域性整体脱贫提供参考,为精准扶贫,打好扶贫攻坚战建言献策. 相似文献
82.
A recent model for Chagas’ disease after stem cell transplantation is extended for a three-dimensional multi-agent-based model. The computational model includes six different types of autonomous agents: inflammatory cell, fibrosis, cardiomyocyte, proinflammatory cytokine tumor necrosis factor-α, Trypanosoma cruzi, and bone marrow stem cell. Only fibrosis is fixed and the other types of agents can move randomly through the empty spaces using the three-dimensional Moore neighborhood. Bone marrow stem cells can promote apoptosis in inflammatory cells, fibrosis regression and can differentiate in cardiomyocyte. T. cruzi can increase the number of inflammatory cells. Inflammatory cells and tumor necrosis factor-α can increase the quantity of fibrosis. Our results were compared with experimental data giving a fairly fit and they suggest that the inflammatory cells are important for the development of fibrosis. 相似文献
83.
《Journal of Terramechanics》2013,50(3):211-232
With the predicted increase in world population to over 10 billion, by the year 2050, growth in agricultural output needs to be continued. Considering this, autonomous vehicles application in precision agriculture is one of the main issues to be regarded noteworthy to improve the efficiency. In this research many papers on autonomous farm vehicles are reviewed from navigation systems viewpoint. All navigation systems are categorized in six classes: dead reckoning, image processing, statistical based developed algorithms, fuzzy logic control, neural network and genetic algorithm, and Kalman filter based. Researches in many agricultural operations from water monitoring to aerial crop scouting revealed that the centimeter level accuracy in all techniques is available and the velocity range for evaluated autonomous vehicles almost is smaller than 1 m/s. Finally it would be concluded although many developments in agricultural automation using different techniques and algorithms are obtained especially in recent years, more works are required to acquire farmer’s consensus about autonomous vehicles. Additionally some issues such as safety, economy, implement standardization and technical service support in the entire world are merit to consideration. 相似文献
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An edge-colored directed graph is observable if an agent that moves along its edges from node to node is able to determine his position in the graph after a sufficiently long observation of the edge colors, and without accessing any information about the traversed nodes. When the agent is able to determine his position only from time to time, the graph is said to be partly observable. Observability in graphs is desirable in situations where autonomous agents are moving on a network and they want to localize themselves with limited information. In this paper, we completely characterize observable and partly observable graphs and show how these concepts relate to other concepts in the literature. Based on these characterizations, we provide polynomial time algorithms to decide observability, to decide partial observability, and to compute the minimal number of observations necessary for finding the position of an agent. In particular we prove that in the worst case this minimal number of observations increases quadratically with the number of nodes in the graph. We then consider the more difficult question of assigning colors to a graph so as to make it observable and we prove that two different versions of this problem are NP-complete. 相似文献
86.
Zhen-Zhou Nie Dr. Meng Wang Dr. Shuai Huang Dr. Zhi-Yang Liu Prof. Hong Yang 《Angewandte Chemie (International ed. in English)》2023,62(25):e202304081
Multimodal self-sustainable autonomous locomotions integrated into one individual system, are high-level intelligent behavioral characteristics of living organisms and are the scientific hotspot of bionic soft actuators. Here, we report a light-fueled soft actuator with multimodal self-sustainable movements based on a Seifert ribbon bounded by a Hopf link. The Seifert ribbon actuator can self-sense the illumination area adjustment, and the actuation component becomes either a discontinuous strip-like structure or a continuous toroidal structure, which can realize adaptive switches between self-sustained oscillatory and rotary motions. The two motion modes are applied to the self-oscillatory piezoelectric generation and self-rotational work multiplication of cargo transport, respectively. The unique smartness of Seifert surface topology advances the level of actuation intelligence with broad implications for the adaptability, multifunctionality, and autonomy of soft robots. 相似文献
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Dr. Clara Patricia Marshall Dr. Julia Schumann Dr. Annette Trunschke 《Angewandte Chemie (International ed. in English)》2023,62(30):e202302971
Heterogeneous catalysis is an important area of research that generates data as intricate as the phenomenon itself. Complexity is inherently coupled to the function of the catalyst and advance in knowledge can only be achieved if this complexity is adequately captured and accounted for. This requires integration of experiment and theory, high data quality and quality control, close interdisciplinary collaboration, and sharing of data and metadata, which is facilitated by the application of joint data management strategies. This Viewpoint Article first discusses the potential of a digital transition in catalysis research. Then, a summary of the current status in terms of data infrastructure in heterogeneous catalysis is presented, defining the various types of (meta-) data, from catalyst synthesis to functional analysis. Finally, an already implemented working concept for local data acquisition and storage is introduced and the benefits and further development directions for catalysis data use and sharing are discussed. 相似文献