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31.
传统温度监测系统大都采用有线测控,系统前期需要完成庞大而复杂的网络布线工程,节点表现为投资成本大、难维护等特点,不利于温度监测系统的大规模推广。而采用STC89C52单片机控制器与nRF24L01无线射频芯片的WSN温度监测节点的设计方案,所设计节点具有成本低、易维护、体积小、低功耗等特点,方案非常适合人们在生产、生活中对温度测控的应用。 相似文献
32.
Anthony A. Wright Robert G. Cook Jacquelyne J. Rivera Stephen F. Sands Juan D. Delius 《Learning & behavior》1988,16(4):436-444
Pigeons were trained to match-to-sample with several new methodologies: a large number of stimuli, computer-drawn color picture stimuli, responses monitored by a computer touch screen, stimuli presented horizontally from the floor, and grain reinforcement delivered onto the picture stimuli. Following acquisition, matching-to-sample concept learning was assessed by transfer to novel stimuli on the first exposure to pairs of novel stimuli. One group (trial-unique), trained with 152 different pictures presented once daily, showed excellent transfer (80% correct). Transfer and baseline performances were equivalent, indicating that the matching-to-sample concept had been learned. A second group (2-stimulus), trained with only two different pictures, showed no evidence of transfer. These results are discussed in terms of the effect of numbers of exemplars on previous failures to find concept learning in pigeons, and the implications of the positive finding from this experiment on abstract concept learning and evolutionary cognitive development. 相似文献
33.
省际人口迁移与云南省人口控制研究 总被引:2,自引:0,他引:2
人口迁移是重要的人口现象和社会现象 ,它影响着一定地区的人口总量、人口分布和人口结构。迁移人口的持续增长是现代经济发展的必然产物 ,社会经济发展水平越高 ,人口迁移量越大 ,反之 ,则越小。云南省人口省际迁移在数量、类型、原因、模式上有其特殊性 ,这些特殊性决定和影响着云南省人口的发展 ,针对这些特殊性提出的云南省人口控制对策 ,有利于把握云南省人口迁移的发展动向以及加快云南省人口城市化的进程 ,提高人口素质 ,控制人口数量。 相似文献
34.
莫徽忠 《柳州职业技术学院学报》2007,7(2):80-82,92
简单定义了光纤熔接机的兼容性、准确性和稳定性,并提出了三种可以改善光纤熔接机性能、提高光纤熔接使用者工作效率、提高光纤接续质量和延长光纤熔接设备的使用寿命的途径. 相似文献
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James Powell Theo Wright Paul Newland Chris Creed Brian Logan 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(2):369-389
Is it possible to educate a fire officer to deal intelligently with the command and control of a major fire event he will never have experienced? The authors of this paper believe there is, and present here just one solution to this training challenge. It involves the development of an intelligent simulation based upon computer managed interactive media. The expertise and content underpinning this educational development was provided by the West Midlands Fire Service. Their brief for this training programme was unambiguous and to the point:
- 1 Do not present the trainee with a model answer, because there are no generic fires. Each incident is novel, complex, and often ‘wicked’ in that it changes obstructively as it progresses. Thus firefighting demands that Commanders impose their individual intelligence on each problem to solve it.
- 2 A suitable Educational Simulator should stand alone; operate in real time; emulate as nearly as possible the ‘feel’ of the fireground; present realistic fire progress; incorporate the vast majority of those resources normally present at a real incident; bombard the trainee with information from those sources; provide as few system‐prompts as possible.
- 3 There should also be an interrogable visual debrief which can be used after the exercise to give the trainees a firm understanding of the effects of their actions. This allows them to draw their own conclusions of their command effectiveness. Additionally, such a record of command and control will be an ideal initiator of tutorial discussion.
- 4 The simulation should be realisable on a hardware/software platform of £10 000.
- 5 The overriding importance is that the simulation should ‘emulate as nearly as possible the feelings and stresses of the command role’.
38.
本文通过对高职院校医学生实习管理进行调查,了解他们对高职院校医学生实习管理教学督导、督导结果等问题的看法,构建实习生实习管理督导流程与质量监控环节的对接机制,以充分发挥教学督导在高职医学专业学生实习管理中的作用为目标,构建符合高职院校医学实习教学的"五位一体"督导模式。 相似文献
39.
Two rhesus monkeys learned the auditory abstract concept ofsame/different. They were trained with 38 different environmental and natural sounds, which were arranged in different combinations as training progressed. Upon transfer to 138 different novel stimuli, they performed as well (78.8% correct) on the first exposure to the novel stimuli as they did (77.3%) with their training stimuli. The comparatively large set of training sounds, contact with the sound source, and a special fading procedure are thought to have contributed to the monkeys’ being able to learn this concept. Implications for species’ similarities/differences in cognitive processing are discussed. 相似文献
40.
在传输线理论的基础上,利用有限元(FEM)法计算分层介质中微带线上场的分布,并通过SPICE仿真对其等效电路在不同频率电源激励下产生的串音进行预测.预测结果验证了印制电路板布线遵从“3W”规则的重要性.由此得出结论:3W规则的使用有功于PCB设计满足EMC系统设计标准,并最大限度地减小印制线之间的耦合. 相似文献