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81.
本文论述了在20kA侧插自熔铝电解槽中添加锂盐、镁盐及锂镁盐复合剂的试验过程和技术经济效果。认为在铝电解槽中添加上述盐类在技术上是可行的,在经济上是有利的。对提高铝电解槽的电流效率和降低直流电单耗具有显著作用。  相似文献   
82.
A wake-up receiver with high energy efficiency and low power consumption is proposed for solving the power consuming problems of wireless nodes communication in the Internet of Things. The proposed wake-up receiver based on the wake-up mechanism can effectively schedule the network nodes communication, and use the simple envelope detection structure to achieve frequency down-conversion, which can flexibly manage energy and reduce power consumption. Based on UMC 65nm CMOS process technology, the wake-up receiver is designed and simulated. The results show that it can achieve S11 of -21dBm and a sensitivity of -75dBm at a data rate of 1Mb/s, when operating at the central frequency of 780MHz and input signal adopting an on-off keying (OOK) modulation, and the power consumption is 82μW at 1.2V voltage supply.  相似文献   
83.
To simulate the firing pattern of biological grid cells, this paper presents an improved computational model of grid cells based on column structure. In this model, the displacement along different directions is processed by modulus operation, and the obtained remainder is associated with firing rate of grid cell. Compared with the original model, the improved parts include that: the base of modulus operation is changed, and the firing rate in firing field is encoded by Gaussian-like function. Simulation validates that the firing pattern generated by the improved computational model is more consistent with biological characteristic than original model. Besides, the firing pattern is badly influenced by the cumulative positioning error, but the computational model can also generate the regularly hexagonal firing pattern when the real-time positioning results are modified.  相似文献   
84.
The construction of dams significantly alters flow and sediment regimes with subsequent deleterious effects on the morphological and ecological character of rivers. Effective experimental floods can ameliorate the downstream geomorphic impacts of dams. The traditional view is that large floods are required to perform effective geomorphic work, and the geomorphic outcomes of small floods are often overlooked. Many river restoration frameworks do not consider small floods. Yet, there is evidence that the hydrological characteristics that ameliorate specific geomorphic impacts in a river are unique to each river, and a customised approach to setting the right mix of floods (including small experimental floods) is needed. In this study, we modify an existing flood effectiveness model developed for large floods, for determining the geomorphic effectiveness of small floods in a highly regulated Australian river. Two flood classes were added to the model (medium peak stream power and moderate total energy expenditure), and the flood power characteristics were rescaled to reflect the relative difference in the magnitude of the small floods and the magnitude of the geomorphic work performed. Using a step‐wise approach, this customised model determined the geomorphic effectiveness of small floods. The best flood for ameliorating the geomorphic impacts of flow regulation had medium to long duration (10 to 51 days), high peak unit stream power (77 to 123 Wm?2) and moderate to large total energy expenditure (78,600 to 342,320 × 103 J). This approach to determining flood effectiveness for small floods is applicable to other geomorphically impacted river channels downstream of dams and can be used to inform experimental flood releases for geomorphic outcomes.  相似文献   
85.
针对电动汽车的充电提出一种电价控制策略。聚合管理者集中管理电动汽车的电池,并且考虑用电高峰时电网的电能供给有限,通过电价控制调整充电的需求量。采用自适应动态规划,通过在线网络训练,得到最优的电价策略。仿真结果表明,该自适应电价控制方法能够通过学习电动汽车的移动性和充电过程,从而调整实际充电需求量至期望水平,保证智能电网的稳定运行。  相似文献   
86.
A robust lane detection and tracking system based on monocular vision is presented in this paper.First,the lane detection algorithm can transform raw images into top view images by inverse perspective mapping(IPM),and detect both inner sides of the lane accurately from the top view images.Then the system will turn to lane tracking procedures to extract the lane according to the information of last frame.If it fails to track the lane,lane detection will be triggered again until the true lane is found.In this system,θ-oriented Hough transform is applied to extract candidate lane markers,and a geometrical analysis of the lane candidates is proposed to remove the outliers.Additionally,vanishing point and region of interest(ROI)dynamically planning are used to enhance the accuracy and efficiency.The system was tested under various road conditions,and the result turned out to be robust and reliable.  相似文献   
87.
营销策划情境式教学是对传统营销教学模式的改革和创新,符合技能型人才的培养目标。与传统的营销策划教学模式相比,它更注重学生实际操作能力的培养,强调学生的主体地位,有效地激发了学生学习的主观能动性和兴趣性,是一种培养学生"快乐地学习"的教学理念。  相似文献   
88.
架空输电线路项目扩容改造,当采用倍容导线时,需在技术和经济上对倍容导线进行比较分析。文章对这种导线的种类、特性情况作了介绍,通过在220kV线路上对倍容导线的选择分析,为同类案例的处理提供了借鉴和参考。  相似文献   
89.
模具生产联合体是由小规模企业组成的模具设计、制造联盟,由于设备、工装和人员分属于不同的加盟企业,其作业排序过程非常复杂。为此提出一种复合式模具生产联合体的生产排序方法:依据基本优先规则首先完成单一工序作业,然后对多工序作业用改进遗传算法进行工艺优化,求出最优解和次优解,再使用评价函数法选择最佳作业路线。该方法在生产试验中取得了良好的成效.能较好满足模具用户和加盟企业两方面的需要。  相似文献   
90.
王新武 《轻金属》2004,(8):17-19
本文简述了CO2 气体吸收率的测定原理 ,着重分析了影响连续碳分CO2 气体吸收率的因素 ,提出了提高连续碳分CO2 气体吸收率的途径  相似文献   
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