This book provides an overview of recent innovations and achievements in the broad areas of cyber-physical systems (CPS), including architecture, networking, systems, applications, security, and privacy. The book discusses various new CPS technologies from diverse aspects to enable higher level of innovation towards intelligent life. The book provides insight to the future integration, coordination and interaction between the physical world, the information world, and human beings. The book features contributions from renowned researchers and engineers, who discuss key issues from various perspectives, presenting opinions and recent CPS-related achievements.Investigates how to advance the development of cyber-physical systems Provides a joint consideration of other newly emerged technologies and concepts in relation to CPS like cloud computing, big data, fog computing, and crowd sourcing Includes topics related to CPS such as architecture, system, networking, application, algorithm, security and privacy
上传时间： 2019-04-21
上传用户：danyun
以后再也不用担心写爬虫ip被封，不用担心没钱买代理ip的烦恼了 在使用python写爬虫时候，你会遇到所要爬取的网站有反爬取技术比如用同一个IP反复爬取同一个网页，很可能会被封。如何有效的解决这个问题呢？我们可以使用代理ip，来设置代理ip池。 现在教大家一个可获取大量免费有效快速的代理ip方法，我们访问西刺免费代理ip网址 这里面提供了许多代理ip，但是我们尝试过后会发现并不是每一个都是有效的。所以我们现在所要做的就是从里面提供的筛选出有效快速稳定的ip。 以下介绍的免费获取代理ip池的方法： 优点：免费、数量多、有效、速度快 缺点：需要定期筛选 主要思路： 从网址上爬取ip地址并存储 验证ip是否能使用-（随机访问网址判断响应码） 格式化ip地址 代码如下： 1.导入包 import requests from lxml import etree import time 1 2 3 2.获取西刺免费代理ip网址上的代理ip def get_all_proxy(): url = 'http://www.xicidaili.com/nn/1' headers = { 'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36', } response = requests.get(url, headers=headers) html_ele = etree.HTML(response.text) ip_eles = html_ele.xpath('//table[@id="ip_list"]/tr/td[2]/text()') port_ele = html_ele.xpath('//table[@id="ip_list"]/tr/td[3]/text()') proxy_list = [] for i in range(0,len(ip_eles)): proxy_str = 'http://' + ip_eles[i] + ':' + port_ele[i] proxy_list.append(proxy_str) return proxy_list 1 2 3 4 5 6 7 8 9 10 11 12 13 14 3.验证获取的ip def check_all_proxy(proxy_list): valid_proxy_list = [] for proxy in proxy_list: url = 'http://www.baidu.com/' proxy_dict = { 'http': proxy } try: start_time = time.time() response = requests.get(url, proxies=proxy_dict, timeout=5) if response.status_code == 200: end_time = time.time() print('代理可用：' + proxy) print('耗时:' + str(end_time - start_time)) valid_proxy_list.append(proxy) else: print('代理超时') except: print('代理不可用--------------->'+proxy) return valid_proxy_list 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 4.输出获取ip池 if __name__ == '__main__': proxy_list = get_all_proxy() valid_proxy_list = check_all_proxy(proxy_list) print('--'*30) print(valid_proxy_list) 1 2 3 4 5 技术能力有限欢迎提出意见，保证积极向上不断学习 ———————————————— 版权声明：本文为CSDN博主「彬小二」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/qq_39884947/article/details/86609930
上传时间： 2019-11-15
上传用户：fygwz1982
This book provides technical information about all aspects of 3GPP LTE. The areas covered range from basic concepts to research-grade material, including future directions. The book captures the current state of 3GPP LTE technology and serves as a source of comprehensive reference material on this subject. It has a total of 12 chapters authored by 50 experts from around the world. The targeted audi- ence includes professionals who are designers or planners for 3GPP LTE systems, researchers (faculty members and graduate students), and those who would like to learn about this field.
标签： Technology Cellular Radio 3GPP LTE and
上传时间： 2020-05-26
上传用户：shancjb
The core thrust of architecture has been to define core business requirements, and then construct the IT solution to meet those requirements, typically as instances of software. While this seems like a simple concept, many in enter- prise IT went way off course in the last 10 to 15 years.
标签： Architecture Revolution Agile
上传时间： 2020-05-26
上传用户：shancjb
Mobile communication devices like smart phones or tablet PCs enable us to consume information at every location and at every time. The rapid development of new applications and new services and the demand to access data in real time create an increasing throughput demand. The data have to be transmitted reliably to ensure the desired quality of service. Furthermore, an improved utilization of the bandwidth is desired to reduce the cost of transmission.
标签： Architectures Processing Baseband Signal for
上传时间： 2020-05-26
上传用户：shancjb
It is commonly accepted today that optical fiber communications have revolutionized telecommunications. Indeed, dramatic changes have been induced in the way we interact with our relatives, friends, and colleagues: we retrieve information, we entertain and educate ourselves, we buy and sell, we organize our activities, and so on, in a long list of activities. Optical fiber systems initially allowed for a significant curb in the cost of transmission and later on they sparked the process of a major rethinking regarding some, generation-old, telecommunication concepts like the (OSI)-layer definition, the lack of cross-layer dependency, the oversegmentation and overfragmentation of telecommunica- tions networks, and so on.
上传时间： 2020-05-27
上传用户：shancjb
Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.
标签： Communication Optical System Space Free
上传时间： 2020-05-27
上传用户：shancjb
Wireless technologies like GSM, UMTS, LTE, Wireless LAN and Bluetooth have revolutionized the way we communicate by making services like telephony and Internet access available anytime and from almost anywhere. Today, a great variety of technical publications offer background information about these technologies but they all fall short in one way or another. Books covering these technologies usually describe only one of the systems in detail and are generally too complex as a first introduction. The Internet is also a good source, but the articles one finds are usually too short and super- ficial or only deal with a specific mechanism of one of the systems. For this reason, it was difficult for me to recommend a single publication to students in my telecommunication classes, which I have been teaching in addition to my work in the wireless telecommunication industry. This book aims to change this.
标签： LTE-Advanced From GSM Pro and 5G to
上传时间： 2020-05-27
上传用户：shancjb
Wireless technologies like GSM, UMTS, LTE, Wireless LAN and Bluetooth have revolu- tionized the way we communicate and exchange data by making services like telephony and Internet access available anytime and from almost anywhere. Today, a great variety of techni- cal publications offer background information about these technologies but they all fall short in one way or another. Books covering these technologies usually describe only one of the systems in detail and are generally too complex as a first introduction. The Internet is also a good source, but the articles one finds are usually too short and superficial or only deal with a specific mechanism of one of the systems. For this reason, it was difficult for me to recom- mend a single publication to students in my telecommunication classes, which I have been teaching in addition to my work in the wireless telecommunication industry. This book aims to change this.
标签： GSM LTE-Advanced
上传时间： 2020-05-27
上传用户：shancjb
Communication, a word that many associate with modern technology, actually has nothing to do with technology. At its core, communication involves nothing more than the spoken or written word, and symbolic languages like art and music. Technology has become synonymous with communication because technology has historically been the method by which communication to or by the general population takes place.
标签： Implementing 802.11
上传时间： 2020-05-27
上传用户：shancjb
