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葛云飞 《中小企业管理与科技》2021,(9)
随着城镇化进程的加快和城市经济辐射能力的增强,以特大城市中心城为核心的都市圈逐渐形成,都市圈内的经济联系更加紧密,都市圈核心区与外围的出行需求迅速增长,市域(郊)铁路的概念被引进,选择符合市域(郊)铁路特点的车辆类型是设计的重点。 相似文献
3.
Advertising situated in environments where people congregate or pass through on their way to somewhere else benefit from being placed in such high traffic areas. However, these strategically placed ads also suffer from conditions of human crowding that prevents them from being noticed and processed. We undertake a study of place-based advertising in a shopping mall using facial recognition software to determine the effect of human density on the attention directed to advertising. We find that as human density increases, attention to advertising decreases, but only to a point where it begins to increase again. Our research also finds that human density plays a moderating role on the motivation to process advertising. 相似文献
4.
Jaehyun So Nassim Motamedidehkordi Yingjie Wu Fritz Busch Keechoo Choi 《International Journal of Sustainable Transportation》2018,12(4):286-298
This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters. 相似文献
5.
In many common law jurisdictions, the common law power of courts to grant assistance in respect of foreign insolvency proceedings exists independently of statute. The nature of the power, however, continues to generate debate. Obiter dicta of the Privy Council suggests that no assistance is available where the foreign proceeding is a voluntary winding‐up. This article evaluates the position by reference to Singapore and Hong Kong decisions and concludes that a refusal to grant assistance in circumstances involving an insolvent voluntary winding‐up is inconsistent with the principle of modified universalism and that a broader recognition test should be adopted. 相似文献
6.
Reinhard Sellmair Tom Schelo 《International Journal of Sustainable Transportation》2019,13(7):479-496
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations. 相似文献
7.
针对空战目标识别中机型自动识别比较困难的问题,提出了采用航迹特征的智能目标识别方法。利用卷积神经网络(Convolutional Neural Network,CNN)分层学习特征的能力,训练CNN算法模型自动地从航迹数据中学习有用的特征并分类。利用沿海实地采集的15个类别的飞机航迹数据,经一系列数据预处理后作为智能识别算法的训练和测试数据,在验证实验中描述了算法网络的相关配置,对比了CNN与其他分类器的识别结果。实验结果表明,CNN具有很好的识别性能。 相似文献
8.
Kareem Mohamed Amr Aziz Belal Mohamed Khaled Abdel‐Hakeem Mostafa Mostafa Ayman Atia 《International Journal of Intelligent Systems in Accounting, Finance & Management》2019,26(4):193-201
Money exchange is one of the most common day‐to‐day activities performed by humans in the daily market. This paper presents an approach to money tracking through a blockchain. The proposed approach consists of three main components: serial number localization, serial number recognition, and a blockchain to store all transactions and ownership transfers. The approach was tested with a total of 110 banknotes of different currency types and achieved an average accuracy of 91.17%. We conducted a user study in real‐time with 21 users, and the mean accuracy across all users was 86.42%. Each user gave us feedback on the proposed approach, and most of them welcomed the idea. 相似文献
9.
Supervisor's human resources (HR) decisions have a significant impact on the employees they manage but have been found to be subject to bias. The upward influence tactics use by subordinates can play a role in this. We investigated the effects of seven upward influence tactics on supervisor job‐performance ratings and the extent of subordinate flexible working arrangements (FWAs). Supervisors are often responsible for determining whether employees are granted FWAs. We posit an alternative theoretical mechanism by which upward influence tactics bring about their effects, mediated through two distinct types of respect, mutual appraisal respect and mutual recognition respect. We collected data from 389 matched supervisor–subordinate dyads, and found that both mutual appraisal respect and mutual recognition respect mediated relationships between several upward influence tactics and both job‐performance ratings and FWAs. Our findings show that upward influence tactics affect the quality of the relationship between employees and their supervisors, specifically, these two forms of mutual respect. Further, both mutual appraisal respect and mutual recognition respect may explain why supervisors show favoritism to some subordinates over others, in reaching HR decisions in these areas. 相似文献
10.
针对卫星数字化视频广播第二代标准(Digital Video Broadcasting-Satellite -Second Generation,DVB-S2)中的多进制幅度移相键控(Multiple Amplitude and Phase-Shift Keying,MAPSK)和多进制正交幅度调制(Multiple Quadrature Amplitude Modulation,MQAM)信号的调制识别,提出了基于位同步的识别方法。首先利用信号星座图特征对信号包络进行位同步,然后统计信号码元的幅度值个数及其幅度值分布提取统计特征参数,最后利用特征参数完成识别。仿真结果表明,所提算法在载波频率等参数未知的条件下,能够有效对信号进行调制识别。 相似文献