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作者： Seward, W.A. Jumper, E.J. Air Force Institute of Technology Wright-Patterson Air Force BaseOH45433 United States Department of Aerospace and Mechanical Engineering University of Notre Dame Notre DameIN46556 United States C17 Aircraft Program Office Aeronautical Systems Division United States

This paper addresses the problem of modeling the catalytic recombination of oxygen on silicon dioxide, the principal material making up the Space Shuttle thermal protection tiles. A new mechanism involving the surface oxygen of the silicon-dioxide matrix itself is proposed. The detailed rate equations describing the proposed mechanism are written and solved at steady state. The predicted rates are shown to match catalytic data specifically collected for the silicon-dioxide/oxygen system. Copyright © 1990 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Silica

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Change in heating energy requirements for various interior space temperatures: A case study of Karabuk

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Energy Education Science and Technology Part A: Energy Science and Research 2013年第4期31卷 1983-1990页

作者： Erturk, Mustafa Alevay Kocyigit, G. Cay, Yusuf Coskun, Can Oktay, Zuhal Balikesir University Vocational College Air Conditioning and Refrigeration Program Balikesir Turkey Balikesir University Institute of Graduate Studies in Science Mechanical Engineering Balikesir Turkey Karabuk University Mechanical Engineering Karabuk Turkey Recep Tayyip Erdogan University Energy Systems Engineering Rize Turkey

In this study, the effect of indoor temperature for heating on reduction of heating load in Karabuk province was studied for various cases. The potential heating degree-hour values for Karabuk are utilized by using average outdoor temperature distribution of the city. Heating degree-hour values of Karabuk province were estimated according to eleven different indoor reference temperatures (18-28°C). The average outdoor temperature distributions of Karabuk are calculated by utilizing the set of the past 32 years obtained from Turkish State Meteorological Services. The results show that heating loads heating load can be decreased by 47.5% and 4.9% for 18 °C and 28 °C indoor design temperatures, respectively. It is considered that these new method is very useful tools for governments to identify the cities with significant potentials for the reduction of the heating loads. © Sila Science.

关键词： Temperature distribution

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Path planning of mobile robots using potential fields and swarms of Brownian particles

Path planning of mobile robots using potential fields and sw...

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Congress on Evolutionary Computation

作者： Helbert Eduardo Espitia Jorge Iván Sofrony Systems Engineering Program Universidad Distrital Francisco José de Caldas Bogota Colombia Department of Mechanical Engineering and Mechatronics Universidad Nacional de Colombia Bogota Colombia

This paper proposes an algorithm for trajectory planning based on the motion of Brownian particles. One of the most popular approaches in path planning is to use the artificial potential fields method which, due to its easiness in implementation, might attract the robot towards a local minimum configuration, thus preventing it from reaching the desired final destination. Although there are different approaches to deal with this drawback, their modeling lacks the simplicity of the potential fields, adding thus an extra complexity to the problem. The solution proposed here combines the strengths of both approaches: it is easy to analyze and to implement, just like in the potentials method, while it preserves the robustness against local minima of more complex particle swarm models. An approximate analysis for the deterministic version of the selected model was performed and it was observed, via simulations, that the results obtained after this simplification were consistent with the behavior of the stochastic system.

关键词： Mathematical model Trajectory Equations Robots Stochastic processes Analytical models

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An Accurate Estimate of Effective Thermal-mechanical Properties of Coreless Circuit Substrate for Advanced Packaging

An Accurate Estimate of Effective Thermal-Mechanical Propert...

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International Conference on Electronics Packaging (ICEP)

作者： W. Y. Jhu H. C. Cheng Department of Aerospace and Systems Engineering Feng Chia University Taichung Taiwan Ph.D Program of Mechanical and Aeronautical Engineering Feng Chia University Taichung Taiwan

This study aims to give an accurate estimate of the effective thermal-mechanical properties of a coreless circuit substrate for advanced IC packages. To achieve the goal, a subdomain-based effective method is proposed, incorporating a sub-domain three-dimensional (3D) copper trace mapping and modeling (TMM) method, a volume-averaging rule of mixture (ROM) technique and finite element modeling. Furthermore, the proposed effective method is combined with an FEA-based process simulation framework to investigate the process-induced warpage of a flip-chip chip scale package during fabrication. At last, parametric analysis is performed to identify the crucial factors influencing the process-induced warpage of the package.

关键词： Solid modeling Three-dimensional displays Predictive models Packaging Electronic packaging thermal management Finite element analysis Flip-chip devices

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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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Optimizing Regulation Functions in Gene Network Identification

Optimizing Regulation Functions in Gene Network Identificati...

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IEEE Annual Conference on Decision and Control

作者： Guilhem Richard A. Agung Julius Calin Belta Program in Bioinformatics Boston University Boston MA 02215 Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute Troy NY 12180 Department of Mechanical Engineering the Division of Systems Engineering Boston University Boston MA 02215

ISBN: (纸本)9781467357159

This paper is concerned with the problem of identifying a discrete-time dynamical system model for a gene regulatory network with unknown topology using time series gene expression data. The topology of such a network can be characterized by a set of regulation hypotheses, one for each gene. In our earlier work, we formulated a convex optimization method to select the regulation hypotheses (and hence the network topology). In this paper, we further optimize the dynamics of the inferred network. Specifically, for a given topology, we minimize the l_2 distance between the experimental data and the model prediction. We illustrate the performance of our algorithm by identifying models for gene networks with known topology.

关键词： gene network identification monotone functions optimization

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Analysis of UPS (ultrasonic positioning system) using DGPS

Analysis of UPS (ultrasonic positioning system) using DGPS

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Annual Conference of Industrial Electronics Society

作者： Su Yong Kim Dong Hwal Lee Hee Tae An Sang Hun Lee Young Ho Koh Man Hyung Lee Department of Mechanical and Intelligent Systems Engineering Pusan National University Busan Korea Depatment of Interdisciplinary Program in Mechatronics Pusan National University Busan Korea School of Mechanical Engineering Pusan National University Busan Korea

ISBN: (纸本)0780387309

In this paper, the position of a mobile robot using DGPS (differential GPS) and UPS (ultrasonic positioning system) is measured and the performance of UPS is analyzed using DGPS. UPS is absolute positioning system using ultrasonic waves and has better performance in low price than the other absolute positioning systems. So in order to evaluate the performance, UPS is compared with the RTK (real-time kinematics) method, which is of the most accurate methods in the DGPS. As a result, the possibility of using UPS can be discussed as pseudolites or pseudosatellites in the place where GPS is not available.

关键词： Performance analysis Global Positioning System Robot kinematics Mobile robots Satellites Electronic mail Position measurement Ultrasonic variables measurement Uninterruptible power systems Robot sensing systems

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Design-informatics approach applicable to real-world problem

Design-informatics approach applicable to real-world problem

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IEEE Symposium on Computational Intelligence in Multi-Criteria Decision-Making, MCDM

作者： Kazuhisa Chiba Yoshikazu Makino Takeshi Takatoya Department of Mechanical Systems Engineering Hokkaido Institute of Technology Sapporo Japan Aviation Program Group Japan AeroSpace Exploration Agency Tokyo Japan

The design-informatics approach has been proposed for next-generation innovative design methodology. The multi-objective problem should be treated in a real-world engineering problem because of the various design requirements. When a multi-objective optimization is implemented, the obtained result is not a sole solution but a set of optimum solutions due to tradeoff relations among design requirements. Therefore, decision-making process is necessary as a post-process for optimization result. In the present study, the design-informatics approach, which is considered as a sequential process between an optimization and its post-process operations, is suggested and is applied to the large-scale and real-world design problem. Consequently, a compromised solution can be efficiently decided from the non-dominated solutions obtained by multidisciplinary design optimization. This approach would be a new efficient procedure for design manner, and also it would be the methodology that innovative design knowledge can be acquired.

关键词： Optimization Aerodynamics Data mining Geometry Analysis of variance Shape Databases

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Ultrasonic satellite system for the positioning of mobile robots

Ultrasonic satellite system for the positioning of mobile ro...

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Annual Conference of Industrial Electronics Society

作者： Jung-Min Lee Dong Hwal Lee HeeTae An Nam Huh Myoung Kook Kim Man Hyung Lee Departement of Interdisciplinary Program in Mechatronics Pusan National University Susan Korea Departement of Mechanical and Intelligent Systems Engineering Pusan National University Busan Korea School of mechanical Engineering Pusan National University Busan Korea

ISBN: (纸本)0780387309

The positioning problem of mobile robot is an important part of control problem for mobile robot. Dead Reckoning is widely used for positioning of mobile robot. However this method has problems because it accumulates estimation errors. In this paper, we propose a new method to increase the accuracy of estimated position using the U-SAT (Ultrasonic Satellite system). U-SAT is composed of a distance measurement using ultrasonic wave and the position acquisition in the world coordinate using the GPS. It is shown that we will be able to estimate the position of mobile robot precisely, in which errors are not accumulated. The experimental results show that the proposed method is enable to estimate the position of the mobile robot.

关键词： Satellites Mobile robots Robot kinematics Global Positioning System Orbital robotics Service robots Estimation error Distance measurement Uncertainty Machine vision

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Thermal Air Braking

Thermal Air Braking

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Novel Intelligent and Leading Emerging Sciences Conference (NILES)

作者： Mohammad M. Abdel Karim Mohamed M. Abdelrahman Amr Guaily Aerospace Department Faculty of Engineering Cairo University Giza Egypt Mechanical Engineering Program School of Engineering and Applied Sciences Smart Engineering Systems Research Center (SESC) Nile University Giza Egypt

This paper introduces the concept of thermal air braking, which involves heating a portion of the airfoil's upper surface to achieve the braking effect. A 2D Computational Fluid Dynamics (CFD) analysis is conducted using ANSYS Fluent software to study the impact of heating the upper back portion of the top surface of an airfoil. The study compares the results of the heated and non-heated cases for NACA 4415. Different aerodynamic efficiencies are investigated, such as lift coefficient (C L ), drag coefficient (C D ), lift-to-drag coefficient (C L /C D ), and pressure coefficient (C P ). The results are promising since there is an increase in the drag coefficient by 70% and a decrease in the lift coefficient by 5%, achieved by heating the last portion of the airfoil.

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