Introduction

Recent Advancements in Airborne Radar Signal Processing - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-5225-5436-3.ch001 ◽

2018 ◽

pp. 1-16

Keyword(s):

Power Loss ◽

High Speed ◽

Estimation Problem ◽

Airborne Radar ◽

Relative Speed ◽

Dynamic Power ◽

Ambiguity Estimation ◽

Range Migration

Although the airborne radar introduced many advantages over other radars, such as ground radars, in detecting high speed air targets, it suffers from many problems. These problems can be concluded as, first, the range migration problem that happens due to the high relative speed between the airborne radar and the high speed air targets and the Doppler ambiguity estimation problem; second, the limited input dynamic power range of the radar receiver and the power loss due to targets range; third, the effects of jamming and clutter which are more effective than ground radars; and finally, the airborne system is a perfect target for enemy threats such as jamming and spoofing.

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Advanced Techniques for Range Detection

Recent Advancements in Airborne Radar Signal Processing - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-5225-5436-3.ch005 ◽

2018 ◽

pp. 85-132

Keyword(s):

Power Loss ◽

High Probability ◽

Probability Of Detection ◽

Airborne Radar ◽

Relative Speed ◽

Radar Systems ◽

Range Migration

Range detection is the main significant goal of radar systems. The radar illuminates the targets to the user and then calculates its parameters. The range is the most important parameter. In Chapter 2, the authors discussed the range detection criteria for the general radar and then emphasized the range detection in airborne radar systems. The range detection in radars suffers from many problems, especially in airborne radar systems where the clutter and jamming are highly affected by the targets' echoes. Also, due to the high relative speed between the air targets and the airborne radar, the range migration problem will happen, and the power loss problem will affect the SNR. So, in order to have a high probability of detection, one must compensate for these problems. This chapter will explain all these problems and how to solve them.

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Panel Discussion--Factors related to perceiving the relative speed of leading vehicles in high-speed rear-end crashes

PsycEXTRA Dataset ◽

10.1037/e572172013-144 ◽

2012 ◽

Author(s):

Michael E. Maddox ◽

Greg Fitch ◽

Aaron Kiefer ◽

Rudolf Mortimer ◽

Jeffrey Muttart

Keyword(s):

High Speed ◽

Panel Discussion ◽

Relative Speed

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Towards an Efficient CNN Inference Architecture Enabling In-Sensor Processing

Sensors ◽

10.3390/s21061955 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1955

Author(s):

Md Jubaer Hossain Pantho ◽

Pankaj Bhowmik ◽

Christophe Bobda

Keyword(s):

Power Consumption ◽

High Speed ◽

Image Sensor ◽

Machine Learning Algorithms ◽

Hierarchical Optimization ◽

Computation Method ◽

Optimization Approach ◽

Efficient Computation ◽

Feature Maps ◽

Dynamic Power

The astounding development of optical sensing imaging technology, coupled with the impressive improvements in machine learning algorithms, has increased our ability to understand and extract information from scenic events. In most cases, Convolution neural networks (CNNs) are largely adopted to infer knowledge due to their surprising success in automation, surveillance, and many other application domains. However, the convolution operations’ overwhelming computation demand has somewhat limited their use in remote sensing edge devices. In these platforms, real-time processing remains a challenging task due to the tight constraints on resources and power. Here, the transfer and processing of non-relevant image pixels act as a bottleneck on the entire system. It is possible to overcome this bottleneck by exploiting the high bandwidth available at the sensor interface by designing a CNN inference architecture near the sensor. This paper presents an attention-based pixel processing architecture to facilitate the CNN inference near the image sensor. We propose an efficient computation method to reduce the dynamic power by decreasing the overall computation of the convolution operations. The proposed method reduces redundancies by using a hierarchical optimization approach. The approach minimizes power consumption for convolution operations by exploiting the Spatio-temporal redundancies found in the incoming feature maps and performs computations only on selected regions based on their relevance score. The proposed design addresses problems related to the mapping of computations onto an array of processing elements (PEs) and introduces a suitable network structure for communication. The PEs are highly optimized to provide low latency and power for CNN applications. While designing the model, we exploit the concepts of biological vision systems to reduce computation and energy. We prototype the model in a Virtex UltraScale+ FPGA and implement it in Application Specific Integrated Circuit (ASIC) using the TSMC 90nm technology library. The results suggest that the proposed architecture significantly reduces dynamic power consumption and achieves high-speed up surpassing existing embedded processors’ computational capabilities.

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Switchmode Hydraulic Power Supply Theory

Fluid Power Systems and Technology ◽

10.1115/imece2005-79019 ◽

2005 ◽

Cited By ~ 7

Author(s):

Jianwei Cao ◽

Linyi Gu ◽

Feng Wang ◽

Minxiu Qiu

Keyword(s):

Flow Rate ◽

Dynamic Characteristics ◽

Power Supply ◽

Power Loss ◽

High Speed ◽

Hydraulic Pressure ◽

Hydraulic Systems ◽

Hydraulic Pump ◽

Hydraulic Power ◽

Supply Pressure

Switchmode hydraulic power supply is a new kind of energy-saving pressure converting system, which is originally proposed by the authors. It is mainly applied in multiple-actuator hydraulic systems, and installed between hydraulic pump and actuators (one switchmode hydraulic power supply for one actuator). It can provide pressure or flow rate that is adapted to the consumption of each actuator in the system by boosting or bucking the pressure, with low power loss, and conveniently, through high-speed switch valves, just like a hydraulic pressure transformer. There are two basic types of switchmode hydraulic power supply: pressure boost and pressure buck. Their structures and working principles are introduced. The dynamic characteristics of two typical types of switchmode hydraulic power supply, the pressure boost type and the pressure buck type, were analyzed through simulations and experiments. The performances were evaluated, and improvements on the efficiency of switchmode hydraulic power supply were proposed.

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LUT Based Generalized Parallel Counters for State - of - art FPGAs

Electronics ETF ◽

10.7251/els1721003k ◽

2017 ◽

Vol 21 (1) ◽

pp. 3

Author(s):

Burhan Khurshid

Keyword(s):

Power Dissipation ◽

High Speed ◽

Critical Path ◽

Experimental Results ◽

Considerable Reduction ◽

Prior Work ◽

Dynamic Power ◽

Look Up Table ◽

State Of Art

Generalized Parallel Counters (GPCs) are frequently used in constructing high speed compressor trees. Previous work has focused on achieving efficient mapping of GPCs on FPGAs by using a combination of general Look-up table (LUT) fabric and specialized fast carry chains. The resulting structures are purely combinational and cannot be efficiently pipelined to achieve the potential FPGA performance. In this paper, we take an alternate approach and try to eliminate the fast carry chain from the GPC structure. We present a heuristic that maps GPCs on FPGAS using only general LUT fabric. The resultant GPCs are then easily re-timed by placing registers at the fan-out nodes of each LUT. We have used our heuristic on various GPCs reported in prior work. Our heuristic successfully eliminates the carry chain from the GPC structure with the same LUT count in most of the cases. Experimental results using Xilinx Kintex-7 FPGAs show a considerable reduction in critical path and dynamic power dissipation with same area utilization in most of the cases.

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Numerical Simulation Investigation on the Windage Power Loss of a High-Speed Face Gear Drive

Energies ◽

10.3390/en12112093 ◽

2019 ◽

Vol 12 (11) ◽

pp. 2093 ◽

Cited By ~ 5

Author(s):

Yu Dai ◽

Feiyue Ma ◽

Xiang Zhu ◽

Jifu Jia

Keyword(s):

Power Loss ◽

High Speed ◽

Outer Radius ◽

Face Gear ◽

Optimal Distance ◽

Inner Radius ◽

Common Goals ◽

Cfd Method ◽

Gear Drives ◽

The Impact

Reducing the energy consumption and improving the efficiency of high-speed transmission systems are increasingly common goals; the windage power loss is not negligible in these methods. In this work, the multi-reference frame (MRF) and periodic boundary conditions (PBC) based on the computational fluid dynamics (CFD) method were adopted to investigate the windage phenomena of a single face gear with and without a shroud, and the impact of the gear speed on the windage power loss was analyzed. Furthermore, the effects on the distribution of static pressure due to the distances between the shroud and the gear body in different directions, including the outer radius direction, the inner radius direction, and the addendum direction were investigated. The results indicate that the gear speed significantly affected the windage loss, as the higher the gear speed was, the greater the windage power loss. Additionally, the shroud could effectively reduce the windage power loss, where the optimal distance from the addendum to the shroud was not the minimum distance; however, for the distances from the shroud to the inner radius and the outer radius, the smaller the distance was, the smaller the windage loss. The results can provide a theoretical basis and technical reference for reducing the windage power loss of various face gear drives.

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Controllers to Chase a High-Speed Evader Using a Pursuer with Variable Speed

Applied Sciences ◽

10.3390/app8101976 ◽

2018 ◽

Vol 8 (10) ◽

pp. 1976 ◽

Cited By ~ 3

Author(s):

Jonghoek Kim

Keyword(s):

Optical Flow ◽

High Speed ◽

Angular Rate ◽

Relative Distance ◽

Line Of Sight ◽

Terminal Phase ◽

Relative Speed ◽

Variable Speed

This paper proposes a chasing controller to enable a pursuer to chase a high-speed evader such that the relative distance between the evader and the pursuer monotonically decreases as time passes. Our controller is designed to assure that the angular rate of Line-of-Sight joining the pair (the pursuer and the evader) is exactly zero at all time indexes. Assuming that the pursuee can readily observe optical flow, but only poorly detect looming, this pursuer’s movement is hardly detected by the pursuee. Consider the terminal phase when the pursuer is sufficiently close to the evader. As we slow down the relative speed of the pursuer with respect to the evader, we can reduce the probability of missing the high-speed evader. Thus, our strategy is to make the pursuer decrease its speed in the terminal phase, while ensuring that the distance between the evader and the pursuer monotonically decreases as time passes. The performance of our controller is verified utilizing MATLAB simulations.

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Thermal Analysis and Test for a High Speed PM Machine for Fan Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.4727 ◽

2011 ◽

Vol 383-390 ◽

pp. 4727-4734 ◽

Cited By ~ 1

Author(s):

Ji Qiang Wang ◽

Feng Xiang Wang

Keyword(s):

Thermal Analysis ◽

Temperature Rise ◽

Power Loss ◽

High Speed ◽

Heat Dissipation ◽

Machine Design ◽

Test Results ◽

Power Losses ◽

Running Speed ◽

High Speed Machine

For a give air flux, the higher speed the fanner is running, the smaller the fanner’s size is. It is also well known that for a given power, the higher the machine’s running speed, the smaller the machine’s size has. If the fanner is geared to a high speed machine directly, the fan set’s volume will be sharply decreased. However, the heat dissipation of the high speed machine becomes a serious problem also due to the small size and high power loss density. Therefore, how to estimate accurately the power losses and temperature rise is a key issue for the high speed machine design. In this paper, the power losses and temperature of high speed PM machine for a fanner application are thoroughly investigated. And the test results of a prototype fan set partly shown the validity of the calculation method.

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