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PARALLEL AND DISTRIBUTED TLM COMPUTATION WITH SIGNAL-PROCESSING FOR ELECTROMAGNETIC-FIELD MODELING

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1995年第3-4期8卷 169-185页

作者： SO, PPM ESWARAPPA, C HOEFER, WJR NSERC/MPR Teltech Research Chair in RF Engineering Department of Electrical and Computer Engineering University of Victoria Victoria British Columbia V8W 3P6 Canada Poman So received his B.Sc. degree in computer science and physics from the University of Toronto Toronto Onatario Canada in 1985. He obtained his B.A. Sc. and M.A.Sc. degrees in electrical engineering (summa cum laude) from the University of Ottawa Ottawa Ontario Canada in 1987 and 1989 respectively. Mr So was a research engineer in the University of Ottawa from January 1989 to October 1991 his research interests included CAD techniques of microwave circuits and numerical methods for electromagnetic wave modelling. He specialized in the development of electromagnetic engineering CAD software and successfully implemented a number of electromagnetic wave simulators based on the two-dimensional and three-dimensional transmission-line matrix methods. From August 1990 to February 1991 he accompanied Professor W. J. R. Hoefer to Rome Italy and Sophia Antiopolas France. During that time he implemented a parallel version of the 3D-TLM simulator for the CM-2 Connection Machine using C-Star and X Windows Library. He is a research engineer and a Ph.D. student at the University of Victoria Victoria British Columbia Canada. He ported the 2D- and 3D-TLM simulators to DECmpp 1200 massively parallel computer using MPL C and C++. He also combined OSA90/hope a commercially available microwave CAD program with a 2D-TLM simulation module for geometry optimization using the Datapipe technique of OSA90/hope. Recently he has developed a distributed client-server computing technique for the TLM method this technique could accelerate the TLM simulation by more than an order of magnitude. Channabasappa Eswarappa received the M.Tech. degree in electrical engineering from the Indian Institute of Technology Kanpur India in 1983 and Ph. D. degree from the University of Ottawa Canada in 1990. He worked as an Assistant Executive Engineer and later as

This paper describes the implementation of transmission-line matrix (TLM) method algorithms on a massively parallel computer (DECmpp 12000), the technique of distributed computing in the UNIX environment, and the combination of TLM analysis with Prony's method as well as with autoregressive moving average (ARMA) digital signal processing for electromagnetic field modelling. By combining these advanced computation techniques, typical electromagnetic field modelling of microwave structures by TLM analysis can be accelerated by a few orders of magnitude.

关键词： Mathematical models

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Phenomenological Model of a Reactive Distillation Column Validated at Pilot-Plant Scale to Produce N-Butyl Lactate

SSRN

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SSRN 2024年

作者： Cesar Augusto, Garcia Echeverry Ochoa, Silvia Gil, Iván Darío Secchi, Argimiro Resende Grupo de Procesos Químicos y Bioquímicos Departamento de Ingeniería Química y Ambiental Universidad Nacional de Colombia Sede Bogotá Cra 30 Num. 45-03 Ed. 453 Of. 318 Cundinamarca Bogotá Colombia SIDCOP Grupo de investigación Universidad de Antioquia Aranjuez Antioquia MedellínCl. 67 53-108 Colombia Chemical Engineering Program LADES—Software Development Laboratory COPPE Universidade Federal do Rio de Janeiro Cidade Universitária Rio de Janeiro Rio de Janeiro21941-914 Brazil

N-butyl lactate is a promising eco-friendly solvent with a high boiling point. However, its production via reactive distillation presents challengessuch as non-linearities and multiple steady states. This work addresses these issues by developing and validating a comprehensive phenomenological model for a pilot-plant scale reactive distillation column, incorporating reaction kinetics and thermodynamic equilibrium. The study examines three cases: 1) Isoamyl acetate production at pilot-plant scale using NRTL-HOC and a pseudo-homogeneous kinetic model with experimental batch data;2) N-butyl lactate production using lab-scale literature data with NRTL, a pseudo-homogeneous kinetic model, and continuous experimental data;3) N-butyl lactate production at pilot-plant scale without experimental data, using NRTL and a pseudo-homogeneous kinetic model. A sensitivity analysis evaluated the model’s robustness, showing that it adequately represents the experimental data on a pilot-plant scale. This research contributes to the development of accurate models for predicting the behavior of processvariables in green solvent production, such as n-butyl lactate, which is crucial for improving industrial-scale process operations. Future research will focus on implementing and evaluating control strategies. © 2024, The Authors. All rights reserved.

关键词： Reaction kinetics

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People counting in crowded and outdoor scenes using a hybrid multi-camera approach

arXiv

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arXiv 2017年

作者： Dittrich, Fabio De Oliveira, Luiz E. S. Britto, Alceu S. Koerich, Alessandro L. Laboratoire d'Imagerie Vision et Intelligence Artificielle Ecole de Technologie Superieure 1100 Notre-Dame West MontrealQCH3A 1E3 Canada Federal University of Paraná Department of Informatics Centro Politécnico Curitiba PR81531-970 Brazil Pontifical Catholic University of Paraná Postgraduate Program in Computer Science R. Imaculada Conceiç aõ 1155 Curitiba PR80215-901 Brazil Ecole de Technologie Supérieure Department of Software and IT Engineering 1100 Notre-Dame West MontrealQCH3A 1E3 Canada

This paper presents two novel approaches for people counting in crowded and open environments that combine the information gathered by multiple views. Multiple camera are used to expand the field of view as well as to mitigate the problem of occlusion that commonly affects the performance of counting methods using single cameras. The first approach is regarded as a direct approach and it attempts to segment and count each individual in the crowd. For such an aim, two head detectors trained with head images are employed: One based on support vector machines and another based on Adaboost perceptron. The second approach, regarded as an indirect approach employs learning algorithms and statistical analysis on the whole crowd to achieve counting. For such an aim, corner points are extracted from groups of people in a foreground image and computed by a learning algorithm which estimates the number of people in the scene. Both approaches count the number of people on the scene and not only on a given image or video frame of the scene. The experimental results obtained on the benchmark PETS2009 video dataset show that proposed indirect method surpasses other methods with improvements of up to 46.7% and provides accurate counting results for the crowded scenes. On the other hand, the direct method shows high error rates due to the fact that the latter has much more complex problems to solve, such as segmentation of heads. Copyright © 2017, The Authors. All rights reserved.

关键词： Cameras

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Transient Thermal Analysis of Welding Fixtures Design

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IOP Conference Series: Earth and Environmental Science 2018年第1期195卷

作者： M T Anual T R Sahroni S Akmal F A Nasution Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka Hang Tuah Jaya 76100 Durian Tunggal Melaka Malaysia Industrial Engineering Department BINUS Graduate Program – Master of Industrial Engineering Bina Nusantara University Jakarta Indonesia 11480 Faculty of Manufacturing Engineering Innovative Software System & Services Research Group Centre for Advanced Computing Technology Universiti Teknikal Malaysia Melaka Hang Tuah Jaya 76100 Durian Tunggal Melaka Malaysia. Industrial Engineering Department Faculty of Engineering Bina Nusantara University Jakarta Indonesia 11480

This paper presents the design and analysis of welding fixtures based on transient thermal analysis. Welding fixtures is designed to hold and support the workpiece securely during the welding process. The heat transformation from the workpiece could lead the temperature rises and impacts to the welding fixtures. Therefore, the study introduces the development of welding fixtures as one of a safety measure prevents the welder from injury while handling welding process. The conceptual design of welding fixtures and material were applied to conduct the simulation. Transient thermal analysis was performed on temperature and total heat flux by using computer aided engineering software. The result shows the analysis of equivalent stress, total deformation, factors of safety, fatigue life and fatigue damage. Furthermore, the equivalent stress failure theory used to predict yielding in welding fixture design. The design of welding fixtures and material selection were proposed to hold and support the workpiece securely.

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Inflatable habitat health monitoring: Implementation, lessons learned, and application to lunar or Martian habitat health monitoring

Inflatable habitat health monitoring: Implementation, lesson...

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作者： Rojdev, Kristina Hong, Todd Hafermalz, Scott Hunkins, Robert Valle, Gerard Toups, Larry NASA Johnson Space Center Houston TX 77058 United States NASA-JSC Systems Architecture and Integration Office University of Southern California - Astronautical Engineering MC: EA-341 2101 NASA Parkway Houston TX 77058 United States Project Management Office MC: EV17 2101 NASA Parkway Houston TX 77058 United States NASA-JSC Avionics Systems Division Electromagnetic Systems Branch MC: EV4 2101 NASA Parkway Houston TX 77058 United States ESCG Electronics and Software Systems NASA-JSC MC: JE22 2101 NASA Parkway Houston TX 77058 United States Systems Architecture and Integration Office NASA-JSC MC: EA-3 2101 NASA Parkway Houston TX 77058 United States Constellation Program Lunar Surface Systems Project Office NASA-JSC MC: ZS1 2101 NASA Parkway Houston TX 77058 United States

ISBN: (纸本)9781563479793

NASA's exploration mission is to send humans to the Moon and Mars, in which the purpose is to learn how to live and work safely in those harsh environments. A critical aspect of living in an extreme environment is habitation, and within that habitation element there are key systems which monitor the habitation environment to provide a safe and comfortable living and working space for humans. Expandable habitats are one of the options currently being considered due to their potential mass and volume efficiencies. This paper discusses a joint project between the National Science Foundation (NSF), ILC Dover, and NASA in which an expandable habitat was deployed in the extreme environment of Antarctica to better understand the performance and operations over a one-year period. This project was conducted through the Innovative Partnership program (IPP) where the NSF provided the location at McMurdo Station in Antarctica and support at the location, ILC Dover provided the inflatable habitat, and NASA provided the instrumentation and data system for monitoring the habitat. The outcome of this project provided lessons learned in the implementation of an inflatable habitat and the systems that support that habitat. These lessons learned will be used to improve current habitation capabilities and systems to meet the objectives of exploration missions to the moon and Mars.

关键词： NASA

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The Joint Tactical Combat Training System system model

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NAVAL ENGINEERS JOURNAL 1997年第3期109卷 293-298页

作者： McCarthy, PJ Munkacsy, M Peter J. McCarthy:is an electrnics engineer at the Naval Air Wrfare Center Training Systems Division in Orlando Florida. He received a B.S. degree in electrical engineering from the University of Illinois at Urbana-Champaign in 1984 and an M.S.E. degree in electical engineering from the Unversity of Central Florida in 1991. He joined the Naval Air Warfare Center in 1985 and worked for seven years on submarine combat system trainingbefore moving to the Modeling and Simulation Development Branch. He is currently a member of the NavAir JTCTS team. Mark J. Munkacsy:is a principal engineer at Raytheon Electronic Systems in Portsmouth RI. He received a B.S. degreein After nuclear power and submarine training he served as weapons officer aboard the USS Boston fast-attack submarine. In 1984 he joined Raytheon and served as lead engineer for the development os submarine-launched Tomahawk fire-control software. He is currently the lead modelingand simulation engineer for the JTCTS program.

The Joint Tactical Combat Training System (JTCTS) is a joint Navy/Air Force program to provide enhanced tactical combat training from single-platform warfighting through integration of multi-platform coordinated combat training (surface, subsurface, and air). Key requirements of JTCTS include the use of the Global Positioning System to generate platform position information, simulated platforms and weapons, and a real-time radio datalink to transmit training data within 400 nm of a JTCTS core-capable site, using a distributed simulation architecture derived from distributed interactive simulations. Many design tradeoffs need to be made to implement this system. To enable the meaningful test and tradeoff of various design options, a software model of the JTCTS system was constructed. This discrete-event simulation was implemented entirely in software running on commercial workstations. The model allows the designers to test various software and hardware design implementations and measure their influence on the ''goodness'' of the exercise data. Based on platform attitude and relative position, datalink connectivity can be assessed and various message-passing algorithms tested. The effects of message latency and communications dropouts on dead-reckoning accuracy can be directly measured. Effects of aircraft antenna shading, atmospheric effects on radio frequency propagation, and others can be turned on or off depending on the needs of the particular test, and to support validation of the model. The engineering model was created during the project concept definition;it is being used today in a number of design studies. One, a datalink transmitter power tradeoff, is giving insight into the relationship between the accuracy of after-action reports and the heat dissipation of the datalink components. These simulated exercises are providing both the end-user and the design team with insight into subsystem and operational interactions usually not seen until system integrati

关键词： Naval warfare

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Annual business and news:: Beginning the 31st year of the Journal of Guidance, Control, and Dynamics

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2008年第1期31卷 1-1页

作者： Schmidt, George T. Aeronautics and Astronautics Massachusetts Institute of Technology (MIT) AIAA Institute of Electrical and Electronics Engineers Russian Federation Academy of Navigation and Motion Control Department of Mechanical and Aerospace Engineering and Engineering Mechanics University of Missouri-Rolla(UMR) Lockheed Electronics Company Center for Space Research University of Texas Austin United States Wright Laboratory Eglin Air Force Base UMR AIAA Guidance Navigation and Control Technical Committee American Automatic Control Council Lockheed Martin Aeronautics Company Palmdale CA United States C4ISR and Unmanned Air Vehicle (UAV) Programs for Air Vehicle Sciences and Systems Accreditation Board Engineering and Technology Inc./Aeronautical National Technical Committee on Guidance Navigation and Control Department of Mechanical and Aerospace Engineering University at Buffalo State University of New York (SUNY) AIAA Technical Committee on GN and C Air Vehicles Directorate Air Force Research Laboratory (AFRL) Wright-Patterson Air Force Base Space Access and Hypersonic Vehicle Guidance and Control Group Control Science Center of Excellence AFRL AIAA Technical Committee on Guidance Navigation and Control Department of Mechanical and Aeronautical Engineering University of California (UC) Davis United States Boeing Company Modernized Flight Control System for the Apache Longbow AIAA Institute of Electrical and Electronics Engineers AHS Jet Propulsion Laboratory California Institute of Technology Boeing Company Flight Sciences and Advanced Design Group Guidance Navigation and Control (GN and C) Systems Engineer Distributed Space Systems NASA Goddard Space Flight Center (GSFC) AIAA GN and C Technical Committee Department of Aerospace Engineering and Engineering Mechanics University of Texas Austin United States Institute of Navigation American Astronautical Society AIAA Guidance Navigation (GN and C) and Control Technical Committee Department of Aerospace Engineering Iowa State University Iowa

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Accelerating Real-Time Imaging for Radiotherapy: Leveraging Multi-GPU Training with PyTorch

Accelerating Real-Time Imaging for Radiotherapy: Leveraging ...

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International Conference on Machine Learning and Applications (ICMLA)

作者： Ruth Obe Brandt Kaufmann Kaelen Baird Sam Kadel Yasmin Soltani Mostafa Cham Matthias K. Gobbert Carlos A. Barajas Zhuoran Jiang Vijay R. Sharma Lei Ren Stephen W. Peterson Jerimy C. PoIf Dept. of Computer Science and of Software Engineering U. of Houston-Clear Lake USA Dept. of Mathematics and Statistics U. of San Francisco USA Dept. of Computer Science and of Mathematics Skidmore College USA Dept. of Computer Science and of Psychology Mount Holyoke College USA Dept. of Biomedical Engineering U. of Houston USA Dept. of Information Systems U. of Maryland Baltimore County Dept. of Mathematics and Statistics U. of Maryland Baltimore County Medical Physics Graduate Program Duke University USA Dept. of Radiation Oncology U. of Maryland School of Medicine USA Department of Radiation Oncology U. of Maryland School of Medicine USA Dept. of Physics U. of Cape Town South Africa H3D Inc. USA

Proton beam therapy is an advanced form of cancer radiotherapy that uses high-energy proton beams to deliver precise and targeted radiation to tumors. This helps to mit-igate unnecessary radiation exposure in healthy tissues. Real-time imaging of prompt gamma rays with Compton cameras has been suggested to improve therapy efficacy. However, the camera's non-zero time resolution leads to incorrect interaction classifications and noisy images that are insufficient for accurately assessing proton delivery in patients. To address the challenges posed by the Compton camera's image quality, machine learning techniques are employed to classify and refine the generated data. These machine-learning techniques include recurrent and feedforward neural networks. A PyTorch model was designed to improve the data captured by the Compton camera. This decision was driven by PyTorch's flexibility, powerful capabilities in handling sequential data, and enhanced G PU usage. This accelerates the model's computations on large-scale radiotherapy data. Through hyperparameter tuning, the validation accuracy of our PyTorch model has been improved from an initial 7 % to over 60 %. Moreover, the PyTorch Distributed Data Parallelism strategy was used to train the RNN models on multiple G PU s, which significantly reduced the training time with a minor impact on model accuracy.

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Szemerédi's regularity lemma application on 3-term arithmetic progression

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AIP Conference Proceedings 2020年第1期2268卷

作者： Regina Ayunita Tarigan Chun-Yen Shen 1Study Program of Software Engineering Techology Institut Teknologi Del Jl. Sisingamangaraja Sitoluama Laguboti Toba Samosir North Sumatra Indonesia 22381 2Department of Mathematics National Taiwan University No. 1 Section 4 Roosevelt Rd Da'an District Taipei City Taiwan 10617

In this paper, the Szemerédi's Regularity Lemma and its application are studied. This lemma is used to partition a large enough graph into almost equal parts so that the number of edges across the parts is fairly random. On the other hand, Roth's Theorem states that there exists an arithmetic progression with length 3 in a subset in integer with positive upper density. We shall see that it can be proved by using triangle removal lemma, which is an application of Szemerédi's Regularity Lemma. The regularity lemma does not seem to be a direct tool to be used on Roth's theorem. The lemma deals with the graphs while Roth's theorem states about subsets on integers. But however, the two are connected through the construction of an auxiliary graph, where 3-arithmetic progression of integers subsets corresponds to triangles in this such graph. At the end of this explanation, we will find that the whole trivial triangles formed by such graph partition are all disjoint. This is at the point we can conclude that there exists an arithmetic progression with length 3 in a subset in integer with positive upper density.

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Development of a DIC-instrumented bubble inflation test: Characterization of ABS thermoforming

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AIP Conference Proceedings 2024年第1期3158卷

作者： S. Rasoul Varedi Burt Buffel Sander Mergan Adrien Scheuer Sam Coppieters Frederik Desplentere Department of Materials Engineering ProPoliS Research Group KU Leuven Bruges Campus Spoorwegstraat 12 8200 Bruges Belgium SIM M3 Program Technologiepark-Zwijnaarde 48 9052 Zwijnaarde Belgium Siemens Industry Software NV Interleuvenlaan 68 3001 Leuven Belgium Department of Materials Engineering Elooi Lab KU Leuven Ghent Campus Gebroeders De Smetstraat 1 9000 Ghent Belgium

This study addresses the mechanical characterization of ABS material under test conditions relevant to the vacuum-forming process. To examine the nonlinear response of the material behavior, a custom-made bubble inflation test setup was linked to a stereo Digital Image Correlation (DIC) system to measure the large deformation behavior during fast inflation of the material in the range of forming temperature (130 to 150°C). To attain the desired temperature, a temperature-control convection oven is employed. To assess the temperature uniformity of the material, an infrared (IR) camera is employed. The IR camera enables to assess the temperature distribution across the material surface. In order to replicate the strain and rate of deformation conditions experienced by the material in actual vacuum forming processes, DIC measurement was performed on a negative semi-sphere mold. By incorporating real-world strain data with a bubble inflation test setup, the experimental conditions closely mimic those encountered in vacuum-forming processes, leading to a more relevant evaluation of the material’s behavior. The main output of this experimental work is to accurately measure the out-of-plane displacement of the material along the centerline during the isothermal inflation process. Subsequently, the collected data will be utilized to calibrate the nonlinear parameters of the material model using the inverse approach using Finite Element Model Updating (FEMU). This methodology ensures that the simulated bubble shape effectively matches the experimental observations at different temperatures during inflation.

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