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Theories of Synthetic Aperture Radar
Published in Maged Marghany, Automatic Detection Algorithms of Oil Spill in Radar Images, 2019
In practice, computing Doppler frequency is not as simple as indicated above. The difficult deceptions in the relative magnitudes of fd and fc. To understand this, let us assume a target that is traveling at approximately 300 m/s. In this case, the target is flying nonstop toward the radar with X-band, i.e., its specific carrier frequency of fc = 10 GHz, with the intention of Ṙ = −v = −300 m/s. Based on the speed of light, the wavelength of X-band is given by: () λ=cfc=3×10810×109=0.03m
Case Study
Published in James Aweya, Designing Switch/Routers, 2023
A key design goal of the BigIron RX Series is to provide high-performance, low-latency, nonstop packet operation (see discussion on redundancy and high-availability features in Chapter 1 of this volume), while meeting the QoS requirements of the respective applications. This chapter describes the architecture of the BigIron RX Series while highlighting the design concepts outlined in the previous chapters and in Volume 1.
Data Clouds and the Environment
Published in Rachel Beth Egenhoefer, Routledge Handbook of Sustainable Design, 2017
Similar to the electricity demand required to operate ICT infrastructure, the equipment associated with that infrastructure carries a necessary environmental burden proportional to the growth in cloud technologies and services. The infrastructure of ICT is made up of millions and millions of servers and other IT equipment that are housed in data center buildings around the world. Material and energy were required to build those data centers. Material and energy were required to build all those servers. And material and energy are required to build the replacements for those servers, which are replaced every few years. Since servers pretty much run nonstop and demand a lot of electricity while being used, the “embodied energy” of these devices – that is, the energy used in obtaining and transporting all the materials needed to manufacture a server, the energy used actually building the server at the server factory, as well as the energy used to ultimately recycle or landfill the server – is much lower than the electricity used to actually operate the server during its lifetime. Embodied energy, however, is not the only sustainability concern in the life cycle of servers. The material demands include certain rare earth materials with limited environmental availability that are sometimes located in conflict zones where purchasing these materials can indirectly support political regimes with human-rights violations. Additionally, many of the materials within the electronic circuitry of the servers contain heavy metals and toxic substances. The improper extraction of these materials and disposal of electronics can lead to health hazards from pollutants leaching into soil and groundwater. These toxic components can also become airborne if certain components are incinerated without the correct protections in place; which can be a challenging issue when electronic waste is often sent across the globe for disposal in countries with less restrictive health and environmental disposal regulations.
Generation of Maximum Power in Grid Connected PV System Based MPPT Control Using Hybrid Elephant Herding Optimization Algorithm
Published in Electric Power Components and Systems, 2022
S. Vijayakumar, C. Govindaraju
3.1.3. Mode P-III. In Figure 2(c), there is no force on the input inductor i.e. current reaches zero and enters into the process of nonstop smuggling. The secondary capacitor and output inductor are omitted. Therefore current and voltage are diminished and DC connection voltage expanded. Correspondingly, the negative half-cycle of the distributed voltage to the inductors and diode and secondary capacitor behavior to achieve the desired function. The PV arrangement model adapted Luo converter and the proposed MPPT controller is elucidated in Section 4.