基于深度学习的跳频信号识别

针对跳频信号分选存在人工提取参数特征具有复杂性的问题，提出了一种基于深度学习的识别方法。首先对跳频信号进行短时傅里叶变换，得到二维的时频矩阵；接着提取信号的轮廓特征，构造三维矩阵作等高线图，并对等高线图进行预处理；最后把预处理后的等高线图输入到卷积神经网络中进行训练、测试，进而实现分类识别。仿真结果表明，在不需要复杂的人工提取参数特征的基础上，在分选率为100〖WT《Times New Roman》〗%〖WTBZ〗时，所提方法经裁剪处理下的信噪比为-15 dB，比支持向量机和传统K-Means聚类算法都低10 dB。实测数据的算法验证表明，所提方法能够将大疆精灵4Pro、hm无人机、司马航模X8HW以及大疆悟2这四类无人机正确分类。     

基于软件无线电平台的1090ES扩容信号收发处理

随着空中交通的信息传输与新应用拓展需求不断增加，1090ES信号容量有限问题日益显现，对1090ES信号进行容量扩充是一种有效解决途径。针对一种基于脉内调相的1090ES信号扩容技术，给出了叠加调制的信号模型，研究了1090ES信号的解调解码算法；在GNU Radio+ USRP软件无线电平台上，实现了1090ES扩容信号的产生和接收处理，包括脉冲位置调制（Pulse Position Modulation，PPM）与8PSK叠加调制、低通滤波、报头检测、载波同步、PPM解码和相位解调等，并利用Matlab对实验的解码错误率和信号的频谱特性做了统计分析与仿真，结果表明了该扩容技术的可行性。     

利用相位差变化趋势的多源信号关联

针对多源信号关联难度大、关联准确率低的问题，利用同一目标平台上搭载的多个辐射源信号具有一致的动态变化趋势这一特点，提出一种利用相位差特征的多源信号关联方法。已知阵列形式和侦测点位置，通过对侦收到的多个辐射源信号进行处理，获取相位差信息并累积形成相位差变化趋势；对比提取疑似相似段，根据相似性判决策略进行有效关联。该方法能有效避免不同传感器对位置测量的误差影响，相比传统基于位置信息关联的方法，能有效提升关联准确率。仿真和实测数据分析证明了该方法的有效性，在阵列形式和侦测点位置已知的条件下该方法具有重要工程意义。     

How Does Using a Mobile Device Change Investors’ Reactions to Firm Disclosures?

I examine how characteristics of investors’ information access tools change investors’ reactions to firm disclosures. I examine my research question in the context of information choice (i.e., allowing investors to choose the order of information and sections to read within a disclosure) and spatial layout (i.e., how information is displayed when viewing the disclosure). Results of an experiment are consistent with information choice improving investors’ judgments if the disclosure is viewed on a computer screen. Conversely, and consistent with cognitive overload, information choice harms investors’ judgments if the disclosure is viewed on a smaller screen, such as that of a mobile device. Follow-up experiments show that changing the disclosure presentation to reduce the need to scroll is one way to improve investors’ judgments on a smaller (or mobile) screen. My findings caution firms and regulators about expanding information choice within disclosures without considering the screen size used to access the disclosure.     

Exploring technology readiness for mobile payment app users

ABSTRACT

The study aims to better understand the various technology readiness segments by assessing how their readiness relates to demographics variables and their adoption, attitude, ease-of-use, usefulness and continuance intention to use mobile payment apps using the technology readiness index. Using a convenience sample of 416 from a consumer panel, a two-step cluster analysis shared similarities with three of the original technology readiness segments (pioneers, paranoids and explorers) while the other two segments clustered together into a fourth segment, hesitant-sceptics. The results indicate that South African mobile users are ready to use mobile payment applications, with the ‘explorer’ emerging as the best segment to target due to optimism levels, while the hesitant-sceptic segment represent the key to unlocking the real potential value of mobile payment apps. Understanding different segments provides marketers with the opportunity to select viable segments and to customise strategies to increase uptake and continued use according to customer needs.     

Exploring the determinants of usage continuance willingness for location-based apps: A case study of bicycle-based exercise apps

This paper investigates how mobile app design and social media can be used to influence the intention for continued use of location-based mobile apps. Uses and gratification theory and information systems success model are used to explore the key factors of continued usage intention. Three hundred and fifty-six valid questionnaires were collected to test the research model. The results showed that perceived usefulness, enjoyment, sense of belonging would significantly influence the usage habit and satisfaction of bicycle-based exercise app. In particular, the habit and satisfaction had strong impact on the intention for continued use. This study extended the findings of exercises with mobile apps and provided implications for the developers and operators of fitness and leisure-oriented apps.     

Co-presence and mobile apps: Technology's impact on being with others

Despite a lack of theoretical understanding regarding how consumers react when using mobile applications in a store, the latter are being used more and more often in shared consumption areas. This research explores the impact that using a mobile application has on perceptions of co-presence. Depending on the consumption experience stage, this technological tool can be a social facilitator that enhances interactions with companions or a device that makes it possible to reduce a negative crowd impression. This paper is positioned at the intersection of interpersonal influence research and research focused on mobile technologies' effect on the purchasing process. It may interest managers of sites where there is high co-presence and where a mobile application might reduce negative crowd impressions and facilitate in-group sharing.     

论移动应用平台的运维运营及技术管控工作

电力企业在移动信息化技术方面也迈出了步伐,开展电力业务现场作业、物资与基建的现场作业、故障抢修等班组作业应用,本文主要讨论移动应用平台的运维和技术管控工作,为移动应用平台的建设和发展提供一种工作思路。     

Mobile Payment and Informal Business: Evidence from China's Household Panel Data

This paper uses household panel data to explore the impact of mobile payments on China's household business activity. Using a difference‐in‐difference fixed effect specification, I find that mobile payment users are more likely to operate small‐scale and self‐employed informal businesses. The impact of using mobile payment primarily derives from the transition of agricultural families to business owners and the development of informal businesses. The paper illustrates an associated increase in employment and income for family members, with more pronounced effects on low‐income and rural households. It also provides prima facie evidence of the increase in fund transfers, which is important for risk sharing that informal businesses may encounter.     

煤矿上山掘进轨道双提升系统的设计及应用

本文介绍了煤矿长斜巷正头掘进与斜巷中段联巷掘进同时施工的新型运输方式。