Abstract—In the future communication applications, users may obtain their messages that have different importance levels distributively from several available sources, such as distributed storage or even devices belonging to other users. This scenario is the best modeled by the multilevel diversity coding systems (MDCS). To achieve perfect (information-theoretic) secrecy against wiretap channels, this paper investigates the fundamental limits on the secure rate region of the asymmetric MDCS (AMDCS), which include the symmetric case as a special case. Threshold perfect secrecy is added to the AMDCS model. The eavesdropper may have access to any one but not more than one subset of the channels but know nothing about the sources, as long as the size of the subset is not above the security level. The question of whether superposition (source separation) coding is optimal for such an AMDCS with threshold perfect secrecy is answered. A class of secure AMDCS (S-AMDCS) with an arbitrary number of encoders is solved, and it is shown that linear codes are optimal for this class of instances. However, in contrast with the secure symmetric MDCS, superposition is shown to be not optimal for S-AMDCS in general. In addition, necessary conditions on the existence of a secrecy key are determined as a design guideline.
标签： Fundamental Limits Secure Class on of
上传时间： 2020-01-04
上传用户：kddlas
shp 文件修复工具（Shape Checker），解决由于dbf文件和shp文件不一致导致打不开的问题.shape文件修复工具免费下载 由ESRI开发，一个ESRI（Environmental Systems Research Institute)的shape文件包括一个主文件，一个索引文件，和一个dBASE表，其中主文件的后缀就是.shp。
标签： shape文件修复工具
上传时间： 2020-03-19
上传用户：sun961920936
High-Speed, Low-Power Dual Operational Amplifier The AD826 features high output current drive capability of 50 mA min per amp, and is able to drive unlimited capacitive loads. With a low power supply current of 15 mA max for both amplifiers, the AD826 is a true general purpose operational amplifier. The AD826 is ideal for power sensitive applications such as video cameras and portable instrumentation. The AD826 can operate from a single +5 V supply, while still achieving 25 MHz of band width. Furthermore the AD826 is fully specified from a single +5 V to ±15 V power supplies. The AD826 excels as an ADC/DAC buffer or active filter in data acquisition systems and achieves a settling time of 70 ns to 0.01%, with a low input offset voltage of 2 mV max. The AD826 is available in small 8-lead plastic mini-DIP and SO packages.
上传时间： 2020-04-19
上传用户：su1254
PRODUCT DESCRIPTION The AD810 is a composite and HDTV compatible, current feedback, video operational amplifier, ideal for use in systems such as multimedia, digital tape recorders and video cameras. The 0.1 dB flatness specification at bandwidth of 30 MHz (G = +2) and the differential gain and phase of 0.02% and 0.04° (NTSC) make the AD810 ideal for any broadcast quality video system. All these specifications are under load conditions of 150 Ω (one 75 Ω back terminated cable). The AD810 is ideal for power sensitive applications such as video cameras, offering a low power supply current of 8.0 mA max. The disable feature reduces the power supply current to only 2.1 mA, while the amplifier is not in use, to conserve power. Furthermore the AD810 is specified over a power supply range of ±5 V to ±15 V.
上传时间： 2020-04-19
上传用户：su1254
Indian urbanization is a complex puzzle which is extremely difficult to comprehend. Yet, as academicians, it is our responsibility to study, comprehend, analyse, assimi- late, and express on salient happenings in our urban systems. The expressions aim at the larger sections of the society to disseminate technical evaluation in a compre- hensible note. This edition focuses on awaking the society on the contextual reality of urban India and also enabling policymakers with the situational understanding of Indian cities.
标签： Inequality Poverty Smart From City
上传时间： 2020-05-26
上传用户：shancjb
Broadband powerline communication systems are continuing to gain significant market adoption worldwide for applications ranging from IPTV delivery to the Smart Grid. The suite of standards developed by the HomePlug Powerline Alliance plays an important role in the widespread deployment of broadband PLC. To date, more than 100 million HomePlug modems are deployed and these numbers continue to rise.
上传时间： 2020-05-26
上传用户：shancjb
We review the current applications of photonic technologies to Smart Cities. Inspired by the future needs of Smart Cities, we then propose potential applications of advanced photonic technologies. We find that photonics already has a major impact on Smart Cities, in terms of smart lighting, sensing, and communication technologies. We further find that advanced photonic technologies could lead to vastly improved infrastructure, such as smart water‐supply systems. We conclude by proposing directions for future research that will have the greatest impact on realizing Smart City initiatives.
上传时间： 2020-05-26
上传用户：shancjb
Smart City Networks: Through the Internet of Things is composed of research results, analyses, and ideas, which focus on a diversity of interconnected factors relating with urbanization, its “smartness,” and overarching “internet of things (IoT).” The latter refers to interconnected objects and devices – through compu- tational operations – which can receive signals and actuate systems.
标签： Networks Internet Through Things Smart City
上传时间： 2020-05-26
上传用户：shancjb
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
Communication between various devices makes it possible to pro- vide unique and innovative services. Although this interdevice com- munication is a very powerful mechanism, it is also a complex and clumsy mechanism, leading to a lot of complexity in present day systems. This not only makes networking difficult but also limits its flexibility.
标签： Wireless Networks Mobile Hoc Ad
上传时间： 2020-05-26
上传用户：shancjb
