International Journal of Computer Vision - Automatic understanding of human affect using visual signals is of great importance in everyday human–machine interactions. Appraising human... 相似文献
The use of unmanned aerial vehicles (UAVs) is rising in several application fields. This work deals with the communication challenges in UAV swarms, or flying ad hoc network (FANET), when taking into account non–line‐of‐sight scenarios. The use of satellites is a necessity in such operating conditions; thus, this work provides architectural considerations and performance assessments when several (FANETs) share an uplink random access satellite channel, fed with M2M/IoT traffic generated from on‐board sensors, to be reliably delivered to a remote ground destination. 相似文献
Recent studies show that the Shewhart median chart is widely used for detecting shifts in a process, but it is often rather inefficient in detecting small or moderate process shifts. In order to overcome this problem, a Synthetic chart can be used. This chart outperforms the Shewhart‐type chart because it uses the information about the time interval between two consecutive nonconforming samples. In this paper, we propose and study the Phase II Synthetic median control chart. A Markov chain methodology is used to evaluate the statistical performance of the proposed chart. Moreover, its performance is investigated in the presence of measurement errors, which are modelled by a linear covariate error model. We provide the results of an extensive numerical analysis with several tables and figures in order to show the statistical performance of the investigated chart, for both cases of measurement errors and no measurement errors. Finally, an example illustrates the use of the Synthetic median chart. 相似文献
The integration of optical satellite links in the next-generation networks and in the fifth generation cellular systems has been proposed in order to guarantee the handling of the extreme data traffic growth and the high-pitched demand for networks’ resources. The optical satellite communication downlink is studied and more specifically, a geostationary satellite with multiple transmitters and an optical ground station with multiple receiving terminals are considered. In this contribution a novel power allocation methodology is proposed for the downlink. The allocation methodology takes into account the scintillation effects due to atmospheric turbulence and maximizes the ergodic network capacity under total expected power and peak power constraints. The analytical optimizing schemes are based on convex optimization methods and have been inspired by waterfilling algorithm. We present emulated power allocation results using real experimental downlink data from ARTEMIS optical satellite campaign and then we investigate the performance of the proposed algorithm with extended numerical results and comparison with other allocation policies. In particular, the new power allocation strategy achieves the highest spectral efficiency, according to the power constraints, for various channel conditions and attenuation profiles and also surpasses two simple baseband allocation methods by intelligently taking advantage of the number of channels and the total expected power.
Quantitative measurements of the apparent rate of reaction of wood rods undergoing fast pyrolysis by contact with a hot spinning steel disc are reported. The variations in the apparent volatilization rate and in the thickness of the reacting layer were studied as a function of disc velocity, rod diameter, contact pressure and disc temperature. The results show that the rate of reaction is mainly limited by heat transfer outside and inside the wood (ablation conditions). The external heat transfer coefficient, studied as a function of contact pressure, is much more important than the heat transfer coefficient calculated on the basis of simple radiation transfer. The conclusion is that fast pyrolysis of wood in the ablation regime can be observed if two necessary conditions are fulfilled : high available heat flux and efficient removal of the primary products of the reaction. 相似文献
The number of cities experiencing population decline has been increasing worldwide. Despite the existence of theoretical propositions of shrinkage as an opportunity to increase levels of residential satisfaction, the issue has not been addressed empirically. This article contributes to fill this gap by assessing, through survey, the residential satisfaction of inhabitants of four shrinking Portuguese cities.
Data were analysed by means of a tree-decision approach: the Chi-squared Automatic Interaction Detection analysis. A sense of safety is the feature that best discriminates inhabitants’ level of residential satisfaction. The results show that shrinkage due to deindustrialisation processes is detrimental to residential satisfaction. 相似文献
There have been many recent advances in wireless communication technologies, particularly in the area of wireless sensor networks, which have undergone rapid development and been successfully applied in the consumer electronics market. Therefore, wireless networks (WNs) have been attracting more attention from academic communities and other domains. From an industrial perspective, WNs present many advantages including flexibility, low cost, easy deployment and so on. Therefore, WNs can play a vital role in the Industry 4.0 framework, and can be used for smart factories and intelligent manufacturing systems. In this paper, we present an overview of industrial WNs (IWNs), discuss IWN features and related techniques, and then provide a new architecture based on quality of service and quality of data for IWNs. We also propose some applications for IWNs and IWN standards. Then, we will use a case from our previous achievements to explain how to design an IWN under Industry 4.0. Finally, we highlight some of the design challenges and open issues that still need to be addressed to make IWNs truly ubiquitous for a wide range of applications. 相似文献