During the past three decades, the world has seen signifi cant changes in the telecom- munications industry. There has been rapid growth in wireless communications, as seen by large expansion in mobile systems. Wireless communications have moved from fi rst-generation (1G) systems primarily focused on voice communications to third-generation (3G) systems dealing with Internet connectivity and multi-media applications. The fourth-generation (4G) systems will be designed to connect wire- less personal area networks (WPANs), wireless local area networks (WLANs) and wireless wide-area networks (WWANs).
标签： Communications Networking Wireless
上传时间： 2020-06-01
上传用户：shancjb
Wirelesscommunications,especiallyinitsmobileform,hasbroughtusthefreedomofmobility andhaschangedthelifestylesofmodernpeople.Waitingatafixedlocationtoreceiveormakea phone call, or sitting in front of a personal computer to send an e-mail or download a video program, has become an old story. Nowadays it is commonplace for people to talk over a cell phonewhilewalkingonthestreet,ortodownloadandwatchamoviewhiletravelingonatrain. Thisisthebenefitmadeavailabletousbythesuccessfulevolutionofwirelesscommunications over three generations, with the fourth generation being under way.
标签： Communications Management Wireless Resource
上传时间： 2020-06-01
上传用户：shancjb
This effort started as an answer to the numerous questions the authors have repeatedly had to answer about electrostatic discharge (ESD) protection and input/output (1/0) designs. In the past no comprehensive book existed suffi- ciently covering these areas, and these topics were rarely taught in engineering schools. Thus first-time I/O and ESD protection designers have had consider- able trouble getting started. This book is in part an answer to such needs.
上传时间： 2020-06-05
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For more than three decades, Micro Electro Mechanical Systems (MEMS) have steadily transitioned out of research labs and into production forming a more than $10 billion market [1]. MEMS devices such as accelerometers, pressure sensors and microphones, to name a few, have seen immense utilization, particularly in the consumer electronics market, because of their compact sizes and minute power consumptions. In addition, these devices benefit from batch fabrication, which has enabled year-over-year reductions in cost [2]. In recent years,
上传时间： 2020-06-06
上传用户：shancjb
Since the 1990s the EU has been pursuing climate change mitigation targets. Following the international commitment to the legally binding greenhouse gas reduction under the Kyoto Protocol, the 2020 policy package consists of a set of binding legislation to ensure that the EU meets its climate and energy targets for the year 2020. The package sets three key targets: 20% reduction in greenhouse gas emissions (from 1990 levels), 20% of EU energy from renewables (as well as a 10% target for renewable fuels) and 20% improvement in energy efficiency. The targets were set by EU leaders in 2007 and enacted in legislation in 2009 3 . They are also headline targets of the Europe 2020 strategy for smart, sustainable and inclusive growth.
标签： Preparatory Ecodesign Study
上传时间： 2020-06-06
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HIS IS THE THIRD —and most likely the last—book in the series on information technology for energy managers and web based energy infor- mation and control systems. This book concentrates on web based enterprise energy and building automation systems, and serves as a capstone volume in this series. The thrust here is that the highest level functions of a building and facility automation system are provided by a web based EIS/ECS system that provides energy management, maintenance management, overall facility operational management, and ties in with the enterprise resource management system for the entire facility or the group of facilities being managed. If there were ever to be a fourth volume in this series, it would follow the logical progression of the first three volumes, and would probably be titled Web Based Enterprise Resource Management Systems.
标签： Enterprise Energy Based Web
上传时间： 2020-06-06
上传用户：shancjb
We are in the era of ubiquitous computing in which the use and development of Radio Frequency Iden- tification (RFID) is becoming more widespread. RFID systems have three main components: readers, tags, and database. An RFID tag is composed of a small microchip, limited logical functionality, and an antenna. Most common tags are passive and harvest energy from a nearby RFID reader. This energy is used both to energize the chip and send the answer back to the reader request. The tag provides a unique identifier (or an anonymized version of that), which allows the unequivocal identification of the tag holder (i.e. person, animal, or items).
上传时间： 2020-06-08
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The purpose of this book is to present detailed fundamental information on a global positioning system (GPS) receiver. Although GPS receivers are popu- larly used in every-day life, their operation principles cannot be easily found in one book. Most other types of receivers process the input signals to obtain the necessary information easily, such as in amplitude modulation (AM) and frequency modulation (FM) radios. In a GPS receiver the signal is processed to obtain the required information, which in turn is used to calculate the user position. Therefore, at least two areas of discipline, receiver technology and navigation scheme, are employed in a GPS receiver. This book covers both areas.
标签： Fundamentals_of_Global_Positionin g_System_Receivers
上传时间： 2020-06-09
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In this new edition of the book, only minor changes were made to the original nine chapters but three new chapters treat topics of increasing interest to GPS users and equipment developers. One topic, improving the GPS receiver sensi- tivity may extend their operations into buildings, which is becoming important for emergency rescue and urban warfare.
标签： Fundamentals_of_Global_Positionin g_System
上传时间： 2020-06-09
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A kinematically redundant manipulator is a serial robotic arm that has more independently driven joints than are necessary to define the desired pose (position and orientation) of its end-effector. With this definition, any planar manipulator (a manipulator whose end-effector motion is restrained in a plane) with more than three joints is a redundant manipulator. Also, a manipulator whose end-effector can accept aspatialposeisaredundant manipulator ifithas morethan sixindependently driven joints. For example, the manipulator shown in Fig. 1.1 has two 7-DOF arms mounted on a torso with three degrees of freedom (DOFs). This provides 10 DOFs for each arm. Since the end-effector of each arm can have a spatial motion with six DOFs, the arms are redundant.
标签： Autonomous Modeling Planning Robots Path
上传时间： 2020-06-10
上传用户：shancjb
