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351.
教育是人类社会文明发展的重要领域,人工智能在教育领域的应用,对教育产生了革命性的影响;同时,也给教育伦理带来了一系列风险和挑战。人工智能在教育应用中导致的伦理困境和可能面临的伦理风险,主要表现在人工智能与教育主体的权利嬗变、算法推荐与学生个性的发展异化、人工情感与人机互动的情感危机、智能感知与教育数据的价值困境这四个方面。为了防范和消除这些伦理风险,“以人为本”“以德为先”“以法为界”是人工智能在教育应用中的理性选择,教育责任则是“可信赖的人工智能应该做什么”伦理准则的实践指向。 相似文献
352.
WANG Rui-min CAO Guang-yi ZHU Xin-jian 《浙江大学学报(A卷英文版)》2007,8(5):741-747
Model and simulation are good tools for design optimization of fuel cell systems. This paper proposes a new hybrid model of proton exchange membrane fuel cell (PEMFC). The hybrid model includes physical component and black-box com-ponent. The physical component represents the well-known part of PEMFC, while artificial neural network (ANN) component estimates the poorly known part of PEMFC. The ANN model can compensate the performance of the physical model. This hybrid model is implemented on Matlab/Simulink software. The hybrid model shows better accuracy than that of the physical model and ANN model. Simulation results suggest that the hybrid model can be used as a suitable and accurate model for PEMFC. 相似文献
353.
Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and fiver water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant puri- fication and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quanti-tative advantages. The contamination of infiltrated fiver water will be reduced by natural attenuation. Clay minerals, iron hy-droxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing fiver discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the fiver discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save. 相似文献
354.
我国民间组织的运行困境与对策 总被引:1,自引:0,他引:1
改革开放以来,我国的民间组织获得了飞速发展,但是也遇到了法律法规滞后、行政化色彩较浓、社会基础薄弱、发展不规范、工作机制不健全等五个方面的运行困境。由于目前政府对社会发展还有很大的影响作用,所以只有在政府的支持和引导下,走"人为建构"之路,才能推动我国民间组织的健康发展。 相似文献
355.
目的:揭示人造草坪不同颗粒填充密度对足球运动员侧切和起动动作表现的影响,并通过动作过程的生物力学数据分析可能的损伤危险。方法:13名男子足球运动员分别在3种不同颗粒密度的人造草坪上进行45°侧切和直线起动动作,采集运动学和动力学数据。结果:随着颗粒密度的增加,鞋与草坪交互面牵引力增大;侧切制动阶段地面反作用力峰值和加载率增大,地面反作用力首次峰值时刻的垂直、前、后分力增大,膝伸力矩增大,内收力矩和外展角度减小;蹬伸阶段地面反作用力分量增大;直线起动的重心加速度无显著差异。结论:鞋与人造草坪交互面的牵引力随填充颗粒的密度增加而增加;在常速助跑情况下,较大的交互面牵引力可以为侧切提供良好的制动能力和蹬伸推进力,但不会对直线起动的运动表现造成影响;交互面牵引力的增大会引起侧切制动阶段地面反作用力相关指标的增大,造成地面反作用力峰值时刻ACL损伤敏感指标的改变,导致更大的损伤风险。 相似文献
356.
本文给出了利用这些新兴技术解决银行档案管理的现实问题的方法:采用区块链技术,保障了电子档案的安全可信性;采用智能OCR技术和知识图谱技术,实现了高级检索功能并充分挖掘了档案内蕴藏的价值,为客户营销和可疑用户分析提供了帮助和支撑. 相似文献
357.
本论文主要讨论的是人工交通系统的基本研究方法。文中首先对我国仿真交通系统发展的现状进行了归纳总结,并得出自上而下的传统的还原式的仿真交通系统研究方法很难或无法解决复杂交通系统所面临的诸多问题,而自下而上的综合型的人工交通系统研究方法为复杂交通系统的研究提供了一条有意义的途径。然后,本文以城市交通为主要研究对象,融合物流系统和生态系统,从系统的观点出发,采用自下而上的基于代理的建模技术,在“不断探索和改善”的原则下,利用人工社会、计算实验、平行系统、交通服务水平指数等方法和理论,结合从定性到定量的综合集成研讨厅方法,在不断探索和改善的原则下,寻求城市交通、物流和生态等城市化问题的有效解决方案,建立城市交通系统全面、协调、可持续发展的新型研究方法和体系。 相似文献
358.
Amalia Levanoni 《Al-Masaq: Islam & the Medieval Mediterranean》2008,20(2):179-205
In spite of its location on the Nile bank, medieval Cairo suffered from serious problems of water supply because of its topography and the Nile regime that necessitated water storing. Direct canalization was not adopted to channel the Nile to inhabited quarters, either on the riverside or inland because of the dangers entailed in an uncontrolled water race during the Nile inundation. The Nile water was safely conveyed inland in canals, dammed by dikes at their mouths on the Nile before the inundation, and opened when the water level reached sixteen arms. Aqueducts and conduits carried the water from the canals to inland open reservoirs, or artificial lakes, around all of which grew residential quarters. The lake waters were transferred to cisterns and above ground tanks that were used as closed water reservoirs before distribution in the residential quarters of Cairo. Scattered in central sites within the quarters, there were the big wells and basins that received water from outside the quarter for distribution to the wells located near the houses, baths and mosque courtyards. The quarters' wells and tanks usually had a common water source and the houses' wells were interconnected by a labyrinth of underground conduits. Residences of the elite and bourgeoisie were equipped with water facilities as befitted their status. The upper middle class often rented qā‘as, exclusive residential units located on the ground floor, equipped with water systems. The lower socio-economic classes, which constituted the majority of the population, lived in standard units in residential complexes that were not equipped with running water but only with water jars. The general public regularly visited public baths for both personal hygiene and leisure, consumed commercially prepared food in the market and sent their clothes for laundering and pressing in the market. 相似文献
359.
本文介绍了一种基于人工神经网络的相位跟踪控制方法,当电网并网时,用于对控制电流与电网电压进行同相位跟踪,以实现对电网电压的同步跟踪。经MATLAB电力系统动态仿真,验证了该文提出的BP控制方法,跟踪性能良好,具有较强地自适应能力。 相似文献
360.
本文介绍了1997年在黄河上游进行人工增雨的试验工作,对人工增雨的效果进行了初步分析,并展望了黄河上游人工增雨的美好前景。 相似文献