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101.
This paper assesses two different theories for explaining consciousness, a phenomenon that is widely considered amenable to scientific investigation despite its puzzling subjective aspects. I focus on Integrated Information Theory (IIT), which says that consciousness is integrated information (as ϕMax) and says even simple systems with interacting parts possess some consciousness. First, I evaluate IIT on its own merits. Second, I compare it to a more traditionally derived theory called Neurobiological Naturalism (NN), which says consciousness is an evolved, emergent feature of complex brains. Comparing these theories is informative because it reveals strengths and weaknesses of each, thereby suggesting better ways to study consciousness in the future. IIT’s strengths are the reasonable axioms at its core; its strong logic and mathematical formalism; its creative “experience-first” approach to studying consciousness; the way it avoids the mind-body (“hard”) problem; its consistency with evolutionary theory; and its many scientifically testable predictions. The potential weakness of IIT is that it contains stretches of logic-based reasoning that were not checked against hard evidence when the theory was being constructed, whereas scientific arguments require such supporting evidence to keep the reasoning on course. This is less of a concern for the other theory, NN, because it incorporated evidence much earlier in its construction process. NN is a less mature theory than IIT, less formalized and quantitative, and less well tested. However, it has identified its own neural correlates of consciousness (NCC) and offers a roadmap through which these NNCs may answer the questions of consciousness using the hypothesize-test-hypothesize-test steps of the scientific method.  相似文献   
102.
The increase in the proportion of elderly in Europe brings with it certain challenges that society needs to address, such as custodial care. We propose a scalable, easily modulated and live assistive technology system, based on a comfortable smart footwear capable of detecting walking behaviour, in order to prevent possible health problems in the elderly, facilitating their urban life as independently and safety as possible. This brings with it the challenge of handling the large amounts of data generated, transmitting and pre-processing that information and analysing it with the aim of obtaining useful information in real/near-real time. This is the basis of information theory. This work presents a complete system aiming at elderly people that can detect different user behaviours/events (sitting, standing without imbalance, standing with imbalance, walking, running, tripping) through information acquired from 20 types of sensor measurements (16 piezoelectric pressure sensors, one accelerometer returning reading for the 3 axis and one temperature sensor) and warn the relatives about possible risks in near-real time. For the detection of these events, a hierarchical structure of cascading binary models is designed and applied using artificial neural network (ANN) algorithms and deep learning techniques. The best models are achieved with convolutional layered ANN and multilayer perceptrons. The overall event detection performance achieves an average accuracy and area under the ROC curve of 0.84 and 0.96, respectively.  相似文献   
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韩谊农  伍悦滨 《实验力学》1993,8(4):329-335
阐述了具有可控人工扰动装置的低背景湍动液体管流系统的研制和评价要点在及在高分子减阻液研究中的应用,并指出了这种实验系统在液体内流研究中的重要意义。  相似文献   
104.
弹性杆与结构接触冲击的冲击力计算研究   总被引:2,自引:0,他引:2  
本文提出了一种将杆与结构的接触冲击问题简化为集中力与集中阻尼的常规结构动力学问题的计算模型。对于大型结构,可采用一种特殊的人工边界,只需对人工边界域内的结构用有限元法进行计算。这种人工边界是齐次的,可根据冲击影响区的大小人为地确定  相似文献   
105.
An in situ artificial micro‐pit fabrication method with an area selective electrochemical measurement technique was applied to investigate the effect of the geometry of artificially formed pits on their localized corrosion behavior in anodized 1000 series aluminum. This technique enables the fabrication of artificial micro‐pits with different aspect ratios (pit depth/pit diameter) in solutions. The aspect ratios of the fabricated artificial micro‐pits in this experiment could be varied from 0.13 to 1.83 by controlling the irradiation time of the focused pulsed YAG laser beam. By applying a constant potential to the final laser‐beam‐irradiated spot in chloride environments, localized dissolution occurred only at the laser beam irradiated area, because the anodic oxide film acted as an insulator. The corrosion current and charge increase with increasing aspect ratio at any applied potential. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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设计并开发了一种人工扰动电离层仿真系统.建立了数值模型,规划出系统总体构造,在实现过程中引入VC、VF混合编程的概念,以达到两种语言优势互补的目的.文中详细论述了VC、VF混合编程对于数据的处理,生成Fortran的动态链接库,以及在VC中调用生成库的技术.通过仿真模拟,得出了电离层加热过程中电子密度、电子温度等随时间演化的规律,及发射电波频率、功率对加热效果的影响.试用证明,该系统有效地模拟了电离层人工扰动的状态,为在我国实施加热工程提供了可靠的科学依据.  相似文献   
110.
It is generally accepted that polyolefins are bioinert. The last years, a new class of photodegradable polyethylene films with pro-oxidants has been developed, exhibiting optimised operational properties in terms of controlled UV and/or thermal ageing leading to an abrupt, predefined to some extent, rapid fragmentation into very small fragments. These photodegradable or fragmentable polyethylene films are promoted in the market for various commercial applications. In some cases, these materials are presented as, or are claimed to be, biodegradable materials. Such materials are already used in agriculture in the form of photodegradable mulching films which become fragmented into small remains after the end of their useful lifetime and are incorporated into the soil. However, it has not been verified yet beyond any doubt, that these remains do in fact biodegrade in natural soil, under what conditions, at which rate and what are their effects in agricultural production, the soil and the environment. An experimental investigation has been carried out focusing on the combined effects of critical factors on the controlled (predefined) photo-chemical degradation of photodegradable mulching LLDPE films with pro-oxidants and the behaviour of their remains in the soil. The analysis of the photo-chemical degradation behaviour presented in this paper was carried out through parallel experiments performed under real field and controlled laboratory conditions. The main factors investigated include materials, exposure time, temperature and UV radiation.  相似文献   
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