Effective Utilization of a System Level Simulation Tool by Proper Selection of an Engine Radiator using the Validated Empirical cum Analytical Approach

2011 ◽  
Author(s):  
Govindaraj D
Keyword(s):  
Analytical Approach ◽  
System Level ◽  
Simulation Tool ◽  
Proper Selection ◽  
Effective Utilization ◽  
System Level Simulation ◽  
Selection Of

scholarly journals Sounding and Signal Simulation of Complex Surface and Subsurface Structures for the WISDOM GPR

2020 ◽  
Author(s):  
Christoph Statz ◽  
Dirk Plettemeier ◽  
Yun Lu ◽  
Wolf-Stefan Benedix ◽  
Sebastian Hegler ◽  
...  
Keyword(s):  
Wave Propagation ◽  
High Resolution ◽  
Time Domain ◽  
Heterogeneous Media ◽  
System Level ◽  
Simulation Tool ◽  
Martian Surface ◽  
Full Wave ◽  
System Level Simulation ◽  
Antenna Characteristics

<p>Key in the interpretation and understanding of WISDOMs ground penetrating RADAR (GPR) measurements is the capability to correctly (and efficiently) simulate the instrument characteristics and the RADAR wave propagation in the Martian subsurface (the signal received by WISDOM), taking into account all relevant effects at large scale. In this contribution we present a ray tracing approach that can be applied to heterogeneous and inhomogeneous media and includes the antenna characteristics of the WISDOM instrument as well as rover structures.</p> <p>The WISDOM GPR is part of the 2022 ESA-Roscosmos ExoMars “Rosalind Franklin” rover payload. It will probe the Martian surface and subface at centimetric resolution and a penetration depth of about 3m. WISDOMs primary scientific objective is the high-resolution characterization of the material distribution within the first few meters of the Martian subsurface as a contribution to the search for evidence of past life [1] and to support the drilling operations [2].</p> <p>The simulation tool consists of two parts: The first part simulates the instrument at system level and generates the signal that is fed into the antenna as well as the receive-filter and discretization characteristic of the instrument (taking into account filters, RF effects and the ADC). The second part simulates the wave propagation of this signal in complex media (inhomogeneous or heterogeneous lossy media) taking into account polarization effects and the WISDOM antenna pattern [3]. This method is a hybrid between conventional raytracing (SBR), differential raytracing and physical optics. The simulation complexity can be granularly controlled and weighed against the level of approximation. It is capable of simulating electrically large domains with an acceptable accuracy yielding good predictions of the propagation properties in Martial soil while being significantly less computationally expensive than conventional full-wave solvers like FEM or the Finite-Differences in Time-Domain Method. <br />The results of the system-level-simulation and the propagation simulation for multiple measurement positions (along a rover track) are then combined (similar to the application of a filter) in order to generate a synthetic radargram. This radargram can be directly compared to the WISDOM measurements.</p> <p>The proposed method is validated using measurements of the WISDOM instrument at analog sites and by reference simulations using the FDTD Method [4]. We present synthetic radargrams as simulation results for several sounding scenarios including the WISDOM antenna characteristics, an inhomogeneous subsurface and lossy materials.</p> <p>The proposed approximation method yields accurate estimates of WISDOM soundings for a complex subsurface while being significantly faster than conventional (full wave) methods. The synthetic radargrams can easily be compared to actual measured data.</p> <p>The research on WISDOM is supported by funding from the Centre National d’Etudes Spatiales (CNES) and the Deutsches Zentrum für Luft- und Raumfahrt (DLR).</p> <p>[1] V. Ciarletti, C. Corbel, D. Plettemeier, P. Cais, S. M. Clifford, S.-E. Hamran, "WISDOM GPR Designed for Shallow and High-Resolution Sounding of the Martian Subsurface", Proceedings of the IEEE, Vol. 99, Issue 5, pp. 824-836, May 2011. <br />[2] V. Ciarletti, S. Clifford, D. Plettemeier and the WISDOM Team, "The WISDOM Radar: Unveiling the Sub surface Beneath the ExoMars Rover and Identifying the Best Locations for Drilling", Astrobiology, Vol. 17, No. 6-7, July 2017 <br />[3] D. Plettemeier et al., "Full polarimetric GPR antenna system aboard the ExoMars rover," 2009 IEEE Radar Conference, Pasadena, CA, 2009, pp. 1-6, doi: 10.1109/RADAR.2009.4977120.<br />[4] C. Statz and D. Plettemeier, "BETSi: An electromagnetic time-domain simulation tool for antennas and heterogeneous media in ground penetration radar and biomedical applications," 2017 Computing and Electromagnetics International Workshop (CEM), Barcelona, 2017, pp. 37-38, doi: 10.1109/CEM.2017.7991875.</p>

Meriel Talbot and the Society for the Overseas Settlement of British Women, 1919–1937

2017 ◽  
Vol 10 (1) ◽  
pp. 32-52
Author(s):  
Bonnie White
Keyword(s):  
Domestic Service ◽  
Agricultural Workers ◽  
British Government ◽  
Early Failure ◽  
Proper Selection ◽  
Domestic Servants ◽  
Female Workers ◽  
Female Migrants ◽  
Post War ◽  
Selection Of

In 1917 the British government began making plans for post-war adjustments to the economy, which included the migration of surplus women to the dominions. The Society for the Overseas Settlement of British Women was established in 1920 to facilitate the migration of female workers to the dominions. Earlier studies have argued that overseas emigration efforts purposefully directed women into domestic service as surplus commodities, thus alleviating the female ‘surplus’ and easing economic hardships of the post-war period. This article argues that as Publicity Officer for the SOSBW, Meriel Talbot targeted women she believed would be ideal candidates for emigration, including former members of the Women's Land Army and affiliated groups. With the proper selection of female migrants, Talbot sought to expand work opportunities for women in the dominions beyond domestic service, while reducing the female surplus at home and servicing the connection between state and empire. Dominion authorities, whose demands for migrant labour vacillated between agricultural workers during the war years and domestic servants after 1920, disapproved of Talbot's efforts to migrate women for work in agriculture. Divergent policies led to the early failure of the SOSBW in 1923.

scholarly journals Design Concepts for NiTiNOL Wires to Function as a Sensor

2021 ◽  
Author(s):  
D. Josephine Selvarani Ruth
Keyword(s):  
Shape Memory Alloy ◽  
Electrical Resistance ◽  
Nickel Titanium ◽  
The Other ◽  
Sensing Element ◽  
Proper Selection ◽  
Design Concepts ◽  
Mechanical Element ◽  
Selection Of ◽  
Inverse Hysteresis

AbstractNickel Titanium Naval Ordinance Laboratory (NiTiNOL) is widely called as a shape memory alloy (SMA), a class of nonlinear smart material inherited with the functionally programmed property of varying electrical resistance during the transformation enabling to be positioned as a sensing element. The major challenge to instrument the SMA wires is to suppress the wires’ nonlinearity by proper selection of two important factors. The first factor is influenced by the mechanical biasing element and the other is to identify the sensing current for the sensing device (SMA wires + biasing). This paper focuses on developing SMA wires for sensing in different orientation types and configurations by removing the non-linearity in the system’s output by introducing inverse hysteresis to the wires through the passive mechanical element.

scholarly journals System Level Simulation of Microgrid Power Electronic Systems

Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 644
Author(s):  
Michal Frivaldsky ◽  
Jan Morgos ◽  
Michal Prazenica ◽  
Kristian Takacs
Keyword(s):  
Smart Grid ◽  
Simulation Model ◽  
Real Time ◽  
Power Converter ◽  
System Level ◽  
Time Behavior ◽  
Operational Parameters ◽  
System Level Simulation ◽  
Time Operation ◽  
The Impact

In this paper, we describe a procedure for designing an accurate simulation model using a price-wised linear approach referred to as the power semiconductor converters of a DC microgrid concept. Initially, the selection of topologies of individual power stage blocs are identified. Due to the requirements for verifying the accuracy of the simulation model, physical samples of power converters are realized with a power ratio of 1:10. The focus was on optimization of operational parameters such as real-time behavior (variable waveforms within a time domain), efficiency, and the voltage/current ripples. The approach was compared to real-time operation and efficiency performance was evaluated showing the accuracy and suitability of the presented approach. The results show the potential for developing complex smart grid simulation models, with a high level of accuracy, and thus the possibility to investigate various operational scenarios and the impact of power converter characteristics on the performance of a smart gird. Two possible operational scenarios of the proposed smart grid concept are evaluated and demonstrate that an accurate hardware-in-the-loop (HIL) system can be designed.

A Non-Normality Measure of the Condition Number for Monitoring and Control

1997 ◽  
Vol 119 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Kunsoo Huh ◽  
Jeffrey L. Stein
Keyword(s):  
Optimal Control ◽  
Condition Number ◽  
Minimization Problem ◽  
Monitoring And Control ◽  
Proper Selection ◽  
Modal Structure ◽  
L2 Norm ◽  
And Control ◽  
Normality Measure ◽  
Selection Of

Because the behavior of the condition number can have highly steep and multi-modal structure, optimal control and monitoring problems based on the condition number cannot be easily solved. In this paper, a minimization problem is formulated for κ2(P), the condition number of an eigensystem (P) of a matrix in terms of the L2 norm. A new non-normality measure is shown to exist that guarantees small values for the condition number. In addition, this measure can be minimized by proper selection of controller and observer gains. Application to the design of well-conditioned controller and observer-based monitors is illustrated.

scholarly journals Gem5-X

2021 ◽  
Vol 18 (4) ◽  
pp. 1-27
Author(s):  
Yasir Mahmood Qureshi ◽  
William Andrew Simon ◽  
Marina Zapater ◽  
Katzalin Olcoz ◽  
David Atienza
Keyword(s):  
Visual Recognition ◽  
Energy Savings ◽  
Video Encoding ◽  
System Level ◽  
Heterogeneous Architecture ◽  
Video Analytics ◽  
Smart Systems ◽  
System Level Simulation ◽  
Many Core ◽  
New Applications

The increasing adoption of smart systems in our daily life has led to the development of new applications with varying performance and energy constraints, and suitable computing architectures need to be developed for these new applications. In this article, we present gem5-X, a system-level simulation framework, based on gem-5, for architectural exploration of heterogeneous many-core systems. To demonstrate the capabilities of gem5-X, real-time video analytics is used as a case-study. It is composed of two kernels, namely, video encoding and image classification using convolutional neural networks (CNNs). First, we explore through gem5-X the benefits of latest 3D high bandwidth memory (HBM2) in different architectural configurations. Then, using a two-step exploration methodology, we develop a new optimized clustered-heterogeneous architecture with HBM2 in gem5-X for video analytics application. In this proposed clustered-heterogeneous architecture, ARMv8 in-order cluster with in-cache computing engine executes the video encoding kernel, giving 20% performance and 54% energy benefits compared to baseline ARM in-order and Out-of-Order systems, respectively. Furthermore, thanks to gem5-X, we conclude that ARM Out-of-Order clusters with HBM2 are the best choice to run visual recognition using CNNs, as they outperform DDR4-based system by up to 30% both in terms of performance and energy savings.

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