For more than a century, overhead lines have been the most commonly used technology for transmitting electrical energy at all voltage levels, especially on the highest levels. However, in recent years, an increase in both the number and length of HVAC cables in the transmission networks of different countries like Denmark, Japan or United Kingdom has been observed. At the same time, the construction of offshore wind farms, which are typically connected to the shore through HVAC cables, increased exponentially.
標簽: Electromagnetic Transients Cables Power in
上傳時間: 2020-06-07
上傳用戶:shancjb
Battery systems for energy storage are among the most relevant technologies of the 21 st century. They – in particular modern lithium-ion batteries (LIB) – are enablers for the market success of electric vehicles (EV) as well as for stationary energy storage solutions for balancing fluctuations in electricity grids resulting from the integrationofrenewableenergysourceswithvolatilesupply 1 .BothEVandstationary storage solutions are important because they foster the transition from the usage of fossil energy carriers towards cleaner renewable energy sources. Furthermore, EV cause less local air pollution and noise emissions compared to conventional combustion engine vehicles resulting in better air quality especially in urban areas. Unfortunately, to this day, various technological and economic challenges impede a broad application of batteries for EV as well as for large scale energy storage and load leveling in electricity grids.
標簽: Multiscale Simulation Approach
上傳時間: 2020-06-07
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Today, electric power transmission systems should face many demanding chal- lenges, which include balancing between reliability, economics, environmental, and other social objectives to optimize the grid assets and satisfy the growing electrical demand. Moreover, the operational environment of transmission systems is becoming increasingly rigorous due to continually evolving functions of interconnected power networks from operation jurisdiction to control responsibly – coupled with the rising demand and expectation for reliability.
標簽: Monitoring Protection Wide Area
上傳時間: 2020-06-07
上傳用戶:shancjb
Radio frequency identification (RFID) is a type of automatic identification systems which has gained popularity in recent years for being fast and reliable in keeping track of the individual objects. In RFID systems, contactless object identification is achieved using radio signals without the need for physical contact as the case with other existing identification technologies such as barcodes. Therefore, a huge number of items can be identified in a short amount of time with high reliability and low cost which makes the RFID technology very attractive for a wide range of applications such as supply chain management, e-health, monitoring humans, pets, animals, and many other objects, toll control, and electrical tagging. Furthermore, RFID technology eliminates the human error and reduces the total cost of the products.
上傳時間: 2020-06-08
上傳用戶:shancjb
This book is about global navigation satellite systems (GNSS), their two main instru- ments, which are a receiver and a simulator, and their applications. The book is based on an operational off-the-shelf real-time software GNSS receiver and off-the-shelf GNSS signalsimulator.Theacademicversionsofthesetoolsarebundledwiththisbookandfree for readers to use for study and research.
標簽: Navigation Geophysics Satellite Digital and
上傳時間: 2020-06-09
上傳用戶:shancjb
If one examines the current literature on GPS receiver design, most of it is quite a bit above the level of the novice. It is taken for granted that the reader is already at a fairly high level of understanding and proceeds from there. This text will be an attempt to take the reader through the concepts and circuits needed to be able to understand how a GPS receiver works from the antenna to the solution of user position.
標簽: Fundamentals_of_Global_Positionin g_System
上傳時間: 2020-06-09
上傳用戶:shancjb
Although doing science is at the heart of discovery, the effort would have very limited consequence in the long term without writingscience. As a social enterprise that depends on collaboration, scientific inquiry requires its practi- tioners to write on a regular basis. From time to time, some members of the scientific community have been critical of the overall quality of writing by re- searchers.
標簽: Goldbort_Writing Science for
上傳時間: 2020-06-09
上傳用戶:shancjb
Sound is simply an airborne version of vibration. The air which carries sound is a mixture of gases. In gases, the molecules contain so much energy that they break free from their neighbors and rush around at high speed. As Figure 1.1(a) shows, the innumerable elastic collisions of these high-speed molecules produce pressure on the walls of any gas container. If left undisturbed in a container at a constant temperature, eventually the pressure throughout would be constant and uniform.
標簽: Engineering Audio
上傳時間: 2020-06-09
上傳用戶:shancjb
I can remember buying my first electronic calculator. I was teaching a graduate level statistics course and I had to have a calculator with a square root function. Back in the late 1960s, that was a pretty high-end requirement for a calculator. I managed to purchase one at the “educational discount price” of $149.95! Now, I look down at my desk at an ATmega2560 that is half the size for less than a quarter of the cost and think of all the possibilities built into that piece of hardware. I am amazed by what has happened to everything from toasters to car engines. Who-da-thunk-it 40 years ago?
上傳時間: 2020-06-09
上傳用戶:shancjb
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.
標簽: Autonomous Modeling Planning Robots Path
上傳時間: 2020-06-10
上傳用戶:shancjb