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101.

As the global economy develops rapidly, traffic congestion has become a major problem for first-tier cities in various countries. In order to address the problem of failed real-time control of the traffic flow data by the traditional traffic light control as well as malicious attack and other security problems faced by the intelligent traffic light (ITL) control system, a multi-agent distributed ITL control method was proposed based on the fog computing platform and the Q learning algorithm used for the reinforcement learning in this study, and the simulation comparison was conducted by using the simulation platform jointly constructed based on the VISSIM-Excel VBA-MATLAB software. Subsequently, on the basis of puzzle difficulty of the computational Diffie–Helleman (CDH) and Hash Collision, the applicable security control scheme of ITL under the fog computing was proposed. The results reveal that the proposed intelligent control system prolongs the time of green light properly when the number of vehicles increases, thereby reducing the delay time and retention rate of vehicles; the security control scheme of ITL based on the puzzle of CDH is less efficient when the vehicle density increases, while that based on the puzzle of Hash collision is very friendly to the fog equipment. In conclusion, the proposed control method of ITL based on the fog computing and Q learning algorithm can alleviate the traffic congestion effectively, so the proposed method has high security.

  相似文献   
102.
International Journal of Computer Vision - Occlusion is probably the biggest challenge for human pose estimation in the wild. Typical solutions often rely on intrusive sensors such as IMUs to...  相似文献   
103.
本文简述了对等网络的概念及分类,分析了结构化对等网络特性、存在问题和关键技术,指出结构化对等网络的发展前景。  相似文献   
104.
Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments.  相似文献   
105.
In this paper, an output chattering attenuation scheme is proposed for two tracking controllers. The controllers have integral actions and are used to eliminate the steady-state tracking errors. By designing a compensator and reducing the discontinuous switching, the output chattering at the switching points can be attenuated significantly. Moreover, combining with the generalized Kalman-Yakubovich-Popov (KYP) lemma and the parameter-dependent Lyapunov function method, this problem can be characterized in terms of linear matrix inequality (LMI) formulation. Finally, the simulation results demonstrate the effectiveness of the proposed method.  相似文献   
106.
张帅领  邵钦  林莉峰 《净水技术》2021,40(12):58-62
污泥经干化后进行焚烧已成为市政污泥处理的一种趋势,精确稳定控制进焚烧炉的半干污泥投加量是维持焚烧炉燃烧工况稳定的关键.因半干污泥具有颗粒度不均、黏性高、有弹性、有堆积空隙等固有特性,目前没有直接测量入炉半干污泥投加量的计量仪表,需要通过泵频率或计量装置间接控制入炉污泥量.针对半干污泥计量,研究了在半干污泥输送系统中加入计量槽装置,通过利用料斗内物料减少速率来计算半干污泥流量的计量方法,并给出了计量装置工作的控制过程.该方法在上海市某污泥干化焚烧工程中实际应用的结果表明,与常规的控制污泥输送螺旋频率来测量污泥流量的方法相比,该方法可以实现半干污泥量的精确自动控制,保持焚烧炉燃烧温度和工况相对稳定,取得了良好的效果.  相似文献   
107.
108.
The nucleation efficiency (NE) of stereocomplex crystallites (SCs) formed in asymmetric poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) blends is generally unsatisfactory because the competition between stereocomplexation and chain mixing involved in the melt-mixing process can cause low formation efficiency and even severe aggregation of SCs. Herein, it is attempted to achieve high-efficient formation of finely dispersed SCs particles by designing a unique melt-mixing procedure, where the mixing of PLLA with 0.75 wt% PDLA is first performed at elevated temperatures (far above the melting temperature of SCs) to allow the homogeneous mixing of PLLA/PDLA chains and then at a low temperature (slightly above that of homocrystallites) to permit the full stereocomplexation of the premixed chains. It is found that the SCs formed in the blends exhibit unexpectedly low NEs (e.g., 54.5%), much inferior to that (73.6%) in the counterpart without undergoing premixing. This is because the introduction of premixing leads to a remarkable deterioration in the amount of SCs particles formed, despite decreased particle size, highlighting that the direct mixing at low temperatures of 170–180 °C (about 20–30 °C lower than that used in common melt-processing of PLA) is more effective for the construction of SCs with superior NE. The mechanisms for these striking findings are discussed.  相似文献   
109.
110.
Metallurgical and Materials Transactions A - In this work, we used hydride-dehydride Ti (HDH-Ti) powders (with the oxygen levels of 0.17 and 0.51 wt pct, respectively) combined with microstructural...  相似文献   
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