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Navy's CFC & Halon elimination program

NAVAL ENGINEERS JOURNAL 2000年第1期112卷 91-112页

作者： Toms, GS Breslin, DA Brunner, GP Thill, JC Gregory S. Toms RE:is the CFC & Halon Elimination Program Manager for the Naval Sea Systems Command (NAVSEA). He received a master of science degree in mechanical engineering from the University of Maryland and a B.S. degree in mechanical engineering from West Virginia University. From 1984 to 1997 he was employed at the Naval Surface Warfare Center Carderock Division Annapolis Detachment (formerly David Taylor Research Center) where he worked on the development of advanced centrifugal compressor air conditioning plants for shipboard applications. He received the Stratospheric Ozone Protection Award in 1998 from the U.S. Environmental Protection Agency in recognition of his exceptional leadership and technical achievements in eliminating ozone-depleting substances from Navy ships. He is licensed as a registered Professional Engineer in the state of Texas. David A. Breslin P.E.:is the Director of Technical Operations for the Naval Surface Warfare Center and is the Chairperson of the ASNE Committee on Environmental Engineering. He received a master of science in aerospace engineering from Virginia Tech in 1991 a master of engineering administration in industrial & systems engineering from Virginia Tech in 1991 and a bachelor of engineering in mechanical engineering from Stevens Institute of Technology in 1985. From 1993 to 1997 he was the program manager of the Naval Sea Systems Command's CFC & Halon Elimination Program. Because of his many efforts he received a Stratospheric Ozone Protection Award in 1995 from the U.S. Environmental Protection Agency in recognition of “exceptional contributions to global environmental protection”. Gregory P. Brunner:was employed by the Carderock Division of the Naval Surface Warfare Center and Naval Sea Systems Command (NAVSEA) from 1983 until 1997. From 1993 to 1997 he served as the R&D program manager for the NAVSEA CFC & Halon Elimination Program Office. Program efforts resulted in the development of new refrigerants for backfit into existing shipboard air-conditioning

The domestic production of the most powerful Ozone-Depleting Substances (ODSs) has permanently ceased and the abundant supplies of a number of inexpensive refrigerants, fire-fighting agents, and solvents, once taken for granted, are now a thing of the past. The Navy's original strategy of conserving ODSs, converting systems and processes where feasible, relying on strategic reserves where necessary, and developing "ozone-friendly" equip ment for new-design surface ships and submarines is succeeding. The purpose of this paper is to document the Navy's efforts to date relative to combating the threat to uninterrupted Fleet operations posed by the cessation of ODS production. Specifically, this paper addresses the Navy's shipboard conversion programs for air-conditioning and refrigeration (AC&R) systems, the development of next-generation AC&R systems, the selection of halon substitutes for new-construction fire-fighting systems, and the Navy's alternative to CFC-113 in the cleaning of critical oxygen systems.

关键词： conversion program Ozone depleting substances trichlorotrifluoroethane GRANTS fire fighting strategic reserves Solvents oxygen systems Submarine Halons

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Design, analysis and simulation of biped running robot

Design, analysis and simulation of biped running robot

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IEEE International Workshop on Robot and Human Communication (ROMAN)

作者： Jongwon Park Young Kook Kim Byungho Yoon Kyung-Soo Kim Soohyun Kim School of Mechanical Aerospace and Systems Engineering Korea Advanced Institute of Science and Technology Daejeon South Korea Robotics Program Korea Advanced Institute of Science and Technology Daejeon South Korea

Legged systems are potentially expected to have outstanding mobility. However, they have shown only modest levels of capability to traverse on flat ground. This paper introduces a biped robot inspired by the hind limbs of cats. We present the characteristics of the system and conduct a position analysis based on vector loop equations. Afterwards, the ground clearance and parallel movement of the robotic leg are shown. We present a speed equation in an effort to verify how the major parameters affect the speed. In addition, we explore control strategies for ground speed matching, acceleration, slip, and speed control. A dynamic simulation shows that the biped robot reached 13.31 leg lengths per second (9.3km/h). This biped robot with the speed equation and its control strategies allow us to understand legged locomotion and can show us how to improve the speed.

关键词： Legged locomotion Mathematical model Equations Acceleration Vectors Joints

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Opposition-based shuffled PSO with passive congregation applied to FM matching synthesis

Opposition-based shuffled PSO with passive congregation appl...

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IEEE Congress on Evolutionary Computation

作者： Munoz, Daniel M. Llanos, Carlos H. Dos S. Coelho, Leandro Ayala-Rincon, Mauricio Department of Mechanical Engineering Automation and Control Group/GRACO University of Brasilia Brasilia D.F. Brazil Industrial and Systems Engineering Graduate Program LAS/PPGEPS Pontifical Catholic University of Parana Curitiba Parana Brazil Department of Computer Science and Mathematics University of Brasilia Brasilia D.F. Brazil

ISBN: (纸本)9781424478347

Synthesis of musical instruments or human voice is a time consuming process which requires theoretical and experimental knowledge about the synthesis engine. Commonly, performers need to deal with synthesizer interfaces and a process of trial and error for creating musical sounds similar to a target sound. This drawback can be overcome by adjusting automatically the synthesizer parameters using optimization algorithms. In this paper a hybrid particle swarm optimization (PSO) algorithm is proposed to solve the frequency modulation (FM) matching synthesis problem. The proposed algorithm takes advantage of a shuffle process for exchanging information between particles and applies the selective passive congregation and the opposition-based learning approaches to preserve swarm diversity. Both approaches for injecting diversity are based on simple operators, preserving the easy implementation philosophy of the particle swarm optimization. The proposed hybrid particle swarm optimization algorithm was validated for a three-nested FM synthesizer, which represents a 6-dimensional multimodal optimization problem with strong epistasis. Simulation results revealed that the proposed algorithm presented promising results in terms of quality of solutions. © 2011 IEEE.

关键词： Global optimization

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Comparison between two FPGA implementations of the particle swarm optimization algorithm for high-performance embedded applications

Comparison between two FPGA implementations of the particle ...

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2010 IEEE 5th International Conference on Bio-Inspired Computing: Theories and Applications, BIC-TA 2010

作者： Muñoz, Daniel M. Llanos, Carlos H. Dos S. Coelho, Leandro Ayala-Rincón, Mauricio Department of Mechanical Engineering Automation and Control Group/GRACO University of Brasilia Brasilia D.F. Brazil Industrial and Systems Engineering Graduate Program LAS/PPGPES Pontifical Catholic University of Parana Curitiba Parana Brazil Department of Computer Science and Mathematics University of Brasilia Brasilia D.F. Brazil

ISBN: (纸本)9781424464388

Particle Swarm Optimization (PSO) algorithms have been proposed to solve engineering problems that require to find an optimal point of operation. There are several embedded applications which requires to solve online optimization problems with a high performance. However, the PSO suffers on large execution times, and this fact becomes evident when using Reduced Instruction Set Computer (RISC) microprocessors in which the operational frequencies are low in comparison with the high operational frequencies of traditional personal computers (PCs). This paper compares two hardware implementations of the parallel PSO algorithm using an efficient floating-point arithmetic which perform computations with large dynamic range and high precision. The full-parallel and the partially-parallel PSO architectures allow the parallel capabilities of the PSO to be exploited in order to decrease the running time. Three well-known benchmark test functions have been used to validate the hardware architectures and a comparison in terms of cost in logic area, quality of the solution and performance is reported. In addition, a comparison of the execution time between the hardware and two C-code software implementations, based on a Intel Core Duo at 1.6GHz and a embedded Microblaze microprocessor at 50MHz, are presented. © 2010 IEEE.

关键词： Global optimization

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Accelerating the artificial bee colony algorithm by hardware parallel implementations

Accelerating the artificial bee colony algorithm by hardware...

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2012 IEEE 3rd Latin American Symposium on Circuits and systems, LASCAS 2012

作者： Muñoz, Daniel M. Llanos, Carlos H. Coelho, Leandro Dos S. Ayala-Rincón, Mauricio Department of Mechanical Engineering Automation and Control Group/GRACO University of Brasilia Brasilia D.F. Brazil Industrial and Systems Engineering Graduate Program LAS/PPGEPS Pontifical Catholic University of Parana Curitiba Parana Brazil Department of Computer Science and Mathematics University of Brasilia Brasilia D.F. Brazil

ISBN: (纸本)9781467312080

Artificial bee colony (ABC) is an optimization algorithm inspired on the intelligent behavior of honey bee swarms. It is suitable to be applied when mathematical techniques are impractical or provide suboptimal solutions. As a population-based algorithm, the ABC suffers on large execution times specifically for embedded optimization problems with computational limitations. For that we propose a hardware parallel architecture of the opposition-based ABC algorithm (HPOABC) that facilitates the implementation in Field programmable Gate Arrays (FPGAs). Numerical simulations using four well-known benchmark problems demonstrate that the opposition-based approach allows the algorithm to improve its functionality, preserving the swarm diversity. Additionally, synthesis results point outs that the HPOABC architecture is effectively mapped in hardware and is suitable for embedded applications. © 2012 IEEE.

关键词： Global optimization

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Proposal of an Integration Policy for Heavy Object Handling Technology in a Radiation Environment for the Fusion Device

Proposal of an Integration Policy for Heavy Object Handling ...

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SICE Annual Conference

作者： Shota Ogawa Takahito Maruyama Yuto Noguchi Nobukazu Takeda Department of ITER Project National Institutes for Quantum Science and Technology Ibaraki Japan Doctoral Program in Intelligent and Mechanical Interaction Systems University of Tsukuba Ibaraki Japan

ISBN: (数字)9784907764838

ISBN: (纸本)9798331544461

This paper reports on an integration policy for heavy object handling technologies in radiation environments for the fusion device. The fusion device ITER requires a remote maintenance system using a large manipulator, which poses two significant technical challenges: limited feasible approaches due to the radiation environment and the handling of heavy objects with high precision. This study developed and combined multiple control technologies to address these challenges, such as virtual reality with structural simulator, robot vision with radiation-resistant cameras, and dual peg-in-hole operations with force feedback. In this paper, the authors propose a policy for integrating these multiple control technologies into the system. The test equipment for verification testing was designed and manufactured based on our proposed method. The achievements presented in this paper represent a significant step towards verifying technologies for handling technology of heavy objects with high precision.

关键词： Robot vision systems Force feedback Virtual reality Manipulators Cameras Iron Maintenance Test equipment Proposals Remote control

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Experimental Investigation of Relationship between Inner Ground Resistance Force and Vibration Kinds for Underground Moving Robots

Experimental Investigation of Relationship between Inner Gro...

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Mechatronics and Robotics Engineering (ICMRE), International Conference on

作者： Tomohiro Watanabe Kojiro Iizuka Mechanical Engineering Program Faculty of Engineering Niigata University Niigata City Japan Department of Systems and Engineering and Science Shibaura Institute of Technology Saitama City Japan

ISBN: (数字)9798350394276

ISBN: (纸本)9798350394283

In recent years, there have been many missions where the rovers land and explore the surface of planets or other extraterrestrial bodies. The purpose of these missions is to return the samples of extraterrestrial ground. These samples can solve the planets’ origins and their sources of life. They have not only scientific value but also engineering value. Information on ground characteristics is helpful when building the base. The underground samples are especially valuable because they are not affected by space weathering and keep good conditions. In this background, the rovers, which move underground, have received attention as the method to obtain underground samples. In our previous study, the moving mechanism, which moves underground using vibrations, was proposed. The internal ground resistance decreases when imparting vibrations because the ground particles move and behave like a fluid. On the other hand, the inner ground resistance increases after imparting vibrations because the ground was compacted. The proposed mechanism moves underground while changing the ground condition. This study investigated the relationship between internal ground resistance force and vibration kinds because this relationship helps move underground. In the experiment, inner ground resistance force was measured when an object vibrating was dragged on the ground. In the results, the inner ground resistance force is increased by the vibration whose vibratory force is low. On the other hand, it is decreased by the vibration whose vibratory force is high. This knowledge is valuable for designing the rover’s underground movement using vibrations.

关键词： Vibrations Resistance Knowledge engineering Mechatronics Planets Force Land surface

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Injectable Platelet-Rich Fibrin in Contact with Bone Substitutes, Porous Zirconia, or Laser-Textured Implant Surfaces: A Detailed Morphological Analysis

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Biomedical Materials and Devices 2024年第1期2卷 415-426页

作者： Oliveira, Miguel Noronha Varela, Hugo Almeida Nascimento, Rubens M. Sahoo, Narayan Carvalho, Oscar Henriques, Bruno Souza, Júlio C. M. Ceramic and Composite Materials Research Group (CERMAT) Department of Mechanical Engineering (EMC) Federal University of Santa Catarina (UFSC) Post-graduate Program in Materials Science and Engineering Federal University of Rio Grande Norte (UFRN) Center for MicroElectroMechanical Systems (CMEMS-UMINHO) Universidade do Minho LABBELS - Associate Laboratory University of Minho University Institute of Health Sciences (IUCS) CESPU

The aim of the present study was to perform a detailed morphological analysis of an injectable platelet rich fibrin after combination with two different particulate hydroxyapatite-based granules, a porous zirconia block, and laser-textured zirconia or titanium surfaces. Blood samples were harvested from three participants to prepare the flowable injectable PRF in contact or not with particulate hydroxyapatite (Hap), bone mineral granules (DBBM), porous zirconia blocks, laser-textured titanium or zirconia surfaces. Optical and scanning electron microscopy (SEM) were used to evaluate the fibrin network density, fibrin fibers’ diameter, blood cells, and the interaction of PRF with the biomaterials. Histomorphometry of the flowable PRF was also performed using the hematoxylin–eosin staining protocol. Specimens were independently evaluated by two blinded and well-trained researchers in histomorphometry and microscopy. Particulate Hap and DBBM shown different morphological aspects by SEM analyses since DBBM revealed macro- and micro-scale pores while Hap revealed a dense structure. Hydroxyapatite and DBBM granules were entirely embedded by the fibrin-network in the presence of leukocytes and blood platelets. The zirconia porous structured was filled with PRF and its components. Also, the laser-structured zirconia or implant surfaces were entirely coated with the PRF fibrin network embedding leukocytes and blood platelets. Laser-textured titanium surfaces revealed macro- and micro-scale irregularities that increase the surface area and retention of the injectable PRF. Histomorphometric analyses revealed complementary details on the distribution of lymphocytes, red blood cells, and fibrin associated with platelet aggregation. The flowing and viscosity of an injectable platelet rich fibrin provided an agglomeration of synthetic or xenogeneic particulate bone substitutes and the coating of porous zirconia and textured implant surfaces as inspected by scanning electron microsc

关键词： Bone healing Bone substitutes Histology Morphology Platelet-rich fibrin

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NOMAD: nonlinear manifold decoders for operator learning 22

NOMAD: nonlinear manifold decoders for operator learning

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Proceedings of the 36th International Conference on Neural Information Processing systems

作者： Jacob H. Seidman Georgios Kissas Paris Perdikaris George J. Pappas Graduate Program in Applied Mathematics and Computational Science University of Pennsylvania Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania Department of Electrical and Systems Engineering University of Pennsylvania

ISBN: (纸本)9781713871088

Supervised learning in function spaces is an emerging area of machine learning research with applications to the prediction of complex physical systems such as fluid flows, solid mechanics, and climate modeling. By directly learning maps (operators) between infinite dimensional function spaces, these models are able to learn discretization invariant representations of target functions. A common approach is to represent such target functions as linear combinations of basis elements learned from data. However, there are simple scenarios where, even though the target functions form a low dimensional submanifold, a very large number of basis elements is needed for an accurate linear representation. Here we present NOMAD, a novel operator learning framework with a nonlinear decoder map capable of learning finite dimensional representations of nonlinear submanifolds in function spaces. We show this method is able to accurately learn low dimensional representations of solution manifolds to partial differential equations while outperforming linear models of larger size. Additionally, we compare to state-of-the-art operator learning methods on a complex fluid dynamics benchmark and achieve competitive performance with a significantly smaller model size and training cost.

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Classification of the Structural Integrity by the General Vibration Method

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Procedia Computer science 2019年 157卷 382-387页

作者： Fergyanto E. Gunawan Benfano Soewito Nico Surantha Tuga Mauritsius Nobumasa Sekishita Industrial Engineering Department BINUS Graduate Program - Master of Industrial Engineering Bina Nusantara University Jakarta Indonesia 11480 Computer Science Department BINUS Graduate Program - Master of Computer Science Bina Nusantara University Jakarta Indonesia 11480 Information Systems Information Department BINUS Graduate Program - Master of Information Systems Management Bina Nusantara University Jakarta Indonesia 11480 Department of Mechanical Engineering Toyohashi University of Technology Toyohashi Aichi 441-8580 Japan

Traditionally, for the purpose of classifying the integrity of an engineering structure, one may use the information of the natural frequencies or mode shapes or some other measures derived from the two. In this research, we propose a classification method on the basis of the general vibration model. The general vibration model is essentially a set of differential equations describing the dynamics of the structure under consideration. For the purpose of damage detection, a deviation of the general vibration model from the dynamic equilibrium point marks the occurrence of the damage. To demonstrate the effectiveness of the method, we study two simplest dynamical systems consisting of one- and two-concentrated masses subjected to a prescribed dynamic load. The structural damages are introduced artificially by reducing the stiffness of spring in the structures. We find that the general vibration model is more sensitive to damages than the traditional methods.

关键词： General Vibration Model Structural Integrity Structural Health Monitoring Power Spectral Density Damage Index

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