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作者： Wang, H. Pramanik, N. Roy, U. Sudarsan, R. Sriram, R.D. Lyons', K.W. Knowledge Based Engineering Laboratory Dept. of Mech. Aerospace and Manuf. Engineering Syracuse University Syracuse NY 13244 United States Design and Process Group Systems Integration Division National Institute of Standards and Technology Gaithersburg MD 20899 United States

ISBN: (纸本)0791836215

Traditionally tolerances for manufactured parts are specified using symbolic schemes as per ASME or ISO standards. To use these tolerance specifications in computerized tolerance synthesis and analysis, we need information models to represent the tolerances. Tolerance specifications could be modeled as a class with its attributes and methods [ROY01]. Tolerances impose restrictions on the possible deviation of features from its nominal size/shape. These variations of shape/size of a feature could be modeled as deviation of a set of generalized coordinates defined at some convenient point on the feature [BAL98]. In this paper, we present a method for converting tolerance specifications as per MMC (Maximum Material Condition) / LMC (Least Material Condition) / RFS (Regardless of Feature Size) material conditions for standard mating features (planar, cylindrical, and spherical) into a set of inequalities in a deviation space for representation of deviation of a feature from it's nominal shape. We have used the virtual condition boundaries1 (VCB) as well as tolerance zones (as the case may be) for these mappings. For the planar feature, these relations are linear and the bounded space is diamond shaped. For the other cases, the mapping is a set of nonlinear inequalities. The mapping transforms the tolerance specifications into a generalized coordinate frame as a set of inequalities. These are useful in tolerance synthesis, and analysis as well as in assemblability analysis in the generalized coordinate system (deviation space). In this paper, we also illustrate the mapping procedures with an example. Copyright © 2002 by ASME.

关键词： Mapping

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A scheme for transformation of tolerance specifications to generalized deviation space for use in tolerance synthesis and analysis

A scheme for transformation of tolerance specifications to g...

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28th Design Automation Conference

作者： Wang, H. Pramanik, N. Roy, U. Sudarsan, R. Sriram, R.D. Lyons, K.W. Knowledge Based Eng. Laboratory Dept. of Mech. Engineering Syracuse University Syracuse NY 13244 United States Design and Process Group Systems Integration Division Natl. Inst. of Std. and Technology Gaithersburg MD 20899 United States

ISBN: (纸本)0791836223

关键词： Fits and tolerances

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Jerk limited time optimal control of multi-input systems

Jerk limited time optimal control of multi-input systems

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American control Conference (ACC)

作者： M. Muenchhof T. Singh Department of Mechanical and Aerospace Engineering SUNY at Buffalo Buffalo NY USA Institute of Automatic Control Laboratory of Control Systems and Process Automation University of Technology Darmstadt Darmstadt Germany

A design method for determining control sequences for rest-to-rest maneuvers of flexible structures with multiple actuators and multiple resonant modes is described. The problem formulation. is based on a pole cancellation approach with constraints on both the magnitude and the time rate of change of the control inputs. Time-optimality can be traded for an increased level of robustness with respect to modeling errors. Robustification is achieved by placing additional zeros of the controller on some or all of the resonant poles of the system.

关键词： Optimal control control systems Actuators Automatic control Resonance Sampling methods Aerospace engineering Design methodology Flexible structures Robustness

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Flash lamp annealing technology for ultra-shallow junction formation 3

Flash lamp annealing technology for ultra-shallow junction f...

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3rd International Workshop on Junction Technology, IWJT 2002

作者： Ito, T. Suguro, K. Tamura, M. Taniguchi, T. Ushiku, Y. Iinuma, T. Itani, T. Yoshioka, M. Owada, T. Imaoka, Y. Murayama, H. Kusuda, T. Process and Manufacturing Engineering Center Semiconductor Company Toshiba Corporation 8 Shinsugita-cho Isogo-ku Yokohama Japan TCI Division Toshiba I.S. Corporation Japan Information Systems Center Toshiba Corporation Japan Lamp Technology and Engineering Division Ushio Inc. Japan Development Department for Electronics Equipment Dainippon Screen Mfg. Co. Ltd. Japan

ISBN: (纸本)4891140283

As a new method of activating implanted impurities, flash lamp annealing (FLA) technology is proposed. By optimizing FLA and implantation conditions, junction depth of 14 nm and the sheet resistance of 770 Ω/sq. with good junction leakage were successfully obtained for p+/n junctions without wafer slip and warpage problems. © 2002 JSAP.

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Towards an integrated modeling environment for hypersonic vehicle design and synthesis

Towards an integrated modeling environment for hypersonic ve...

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AIAA/AAAF 11th International Space Planes and Hypersonic systems and Technologies Conference 2002

作者： Zweber, Jeffrey V. Kabis, Hanee Follett, William W. Ramabadran, Narayan Design Process and Environments Team AFRL/VASD Wright Patterson AFB OH 45433 United States Engineering Methods Group Lockheed Martin Missiles and Fire Control Orlando FL 32819 United States Computational Fluid Dynamics Boeing Rocketdyne Division Canoga Park CA 91303 United States TechnoSoft Inc. Cincinnati OH 45242 United States

ISBN: (纸本)9781624101236

The US Air Force Research Laboratory, along with its contractor partners, is developing an integrated modeling environment for the conceptual and preliminary-level design and synthesis of airbreathing, hypersonic vehicles. This effort is built on the team's successful prototype of a similar environment for rocket-powered space access vehicles. The modeling environment under development will begin by developing a 3-4 level deep hierarchy of objects that represent a hypersonic vehicle. Initially, these objects will contain only conceptual-level representations of the geometry and mass properties of the vehicle and its components. This initial information will be used with a vehicle synthesis routine to develop an initial conceptual design. This is typically called the "as drawn" design. The second step in the design process is an initial analysis of the aerodynamic and propulsive characteristics of the vehicle. These analyses will be conducted in the environment and the geometric model that was developed in the initial hierarchy of objects will be of sufficient fidelity to support these analyses. Next, the mass properties, aerodynamic and propulsion analysis results will be used by a trajectory simulation code, also integrated into the environment, to determine if the initial vehicle design will meet the mission performance requirements. Finally, the results of the trajectory simulation will be used to iteratively resize the vehicle until the mission requirements are satisfied. The above process depicts what is known as the closure process, that is, matching the required vehicle propellant fraction for a given mission to the available vehicle propellant fraction. The purpose of the integrated modeling environment is to streamline this closure process. Additionally, this paper will describe the modeling environment used for this effort, lessons learned from the development of the environment for rocket-powered vehicles, and the next steps planned to expand the capabili

关键词： Hypersonic vehicles

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Modeling and simulation of hybrid dynamical systems with generalized differential Petri nets

Modeling and simulation of hybrid dynamical systems with gen...

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IEEE International Symposium on Intelligent control (ISIC)

作者： Yali Wu Weimin Wu Jianchao Zeng Guoji Sun Hongye Su Jian Chu System Engineering Institute Xi''an Jiaotong University Xi'an China Institute of Advanced Process Control National Laboratory of Industrial Control Technology Zhejiang University Hangzhou China Division of System Simulation and Computer Application Taipan Heavy Machinery Institute Taipan China

There has been considerable interest in the modeling and simulation of hybrid dynamic systems (HDS). As an effective modeling tool of discrete event dynamic systems, Petri nets have a dual nature of a graphical tool and a mathematical object. In this paper, an extension of Petri net named generalized differential Petri nets (GDPN) is proposed to model HDS that have a combination of discrete-event evolution and continuous state evolution. Differential place and differential transition defined by Demongodin et al. (1998) are used to model the numeral simulation of the continuous dynamic process, and the weights defined on the directed arcs that connects the differential transitions and places are extended from real numbers to real matrices. The marking of differential place are also enlarged from real numbers to real vectors. Then the evolution rules and modeling method of HDS with GDPN are introduced. Two examples are used to illustrate the modeling power of GDPN in HDS.

关键词： Petri nets Power system modeling Supervisory control Discrete event systems process control Computational modeling Computer simulation Mathematical model Chemical processes Continuous time systems

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Flash lamp annealing technology for ultra-shallow junction formation

Flash lamp annealing technology for ultra-shallow junction f...

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International Workshop on Junction Technology

作者： T. Ito K. Suguro M. Tamura T. Taniguchi Y. Ushiku T. Iinuma T. Itani M. Yoshioka T. Owada Y. Imaoka H. Murayama T. Kusuda Process and Manufacturing Engineering Center Toshiba Corporation Isogo-ku Yokohama Japan Process and Manufacturing Engineering Center Semiconductor Company Toshiba Corporation Yokohama Japan TCI Division Toshiba I.S Corporation Information Systems Center Toshiba Corporation Japan Lamp Technology and Engineering Division Ushio Inc. Development Department for Electronics Equipment Dainippon Screen MFG. Co. Ltd. Development Department for Electronics Equipment Dainippon Screen MFG. Co. Ltd. Yokohama Japan

ISBN: (纸本)4891140283

As a new method of activating implanted impurities, flash lamp annealing (FLA) technology is proposed. By optimizing FLA and implantation conditions, junction depth of 14 nm and the sheet resistance of 770 /spl Omega//sq. with good junction leakage were successfully obtained for p/sup +//n junctions without wafer slip and warpage problems.

关键词： Lamps Temperature Heating Rapid thermal annealing MOSFETs Electrical resistance measurement Indium tin oxide Manufacturing processes Electronic equipment manufacture Semiconductor device manufacture

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Error Bounds for Steel Tensile Strength Prediction—Comparison of Bayesian and Ensemble Model Approaches

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IFAC Proceedings Volumes 2001年第18期34卷 205-210页

作者： Y.Y. Yang D.A. Linkens Institute for Microstructural and Mechanical Process Engineering Department of Automatic Control & Systems Engineering University of Sheffield Sheffield SI 3JD UK

One of the obstacles to applying neural networks in industry is a lack of confidence in model predictions. Recently, there has been increased interest in tackling this lack of confidence by adding error bounds on predictions. In this paper, Bayesian networks and ensemble modelling approaches have been applied to establish the error bounds. A brief introduction to these two approaches is given together with discussion on their merits and drawbacks for error bounds calculation. The two error bound calculation methods are demonstrated with modelling examples from simple function to complicated industrial steel tensile strength data. We show that for complicated problems, creditable error bounds are very difficult to obtain via the Bayesian approach, since it involves many design parameters which are very difficult to define and because some assumptions made in the Bayesian approach on error bound calculation are hard to satisfy. The ensemble modelling approach, however, gives a much robust prediction on error bounds. It shows that the error bounds for the steel tensile strength prediction are consistent with existing metallurgical experience.

关键词： Neural network error bounds Bayesian network ensemble model tensile strength steel

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Nonlinear model predictive control utilizing a neuro-fuzzy predictor

Research Reports on Information Science and Electrical Engin...

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Research Reports on Information Science and Electrical engineering of Kyushu University 2001年第1期6卷 39-45页

作者： Waller, J.B. Hu, J. Hirasawa, K. Process Control Lab. Abo Akademi University 20500 Abo Finland Department of Electrical and Electronic Systems Engineering

This paper applies a quasi-ARMAX modeling technique, recently presented in the literature, to a process control framework. The use of this quasi-ARMAX modeling technique in nonlinear model predictive control (NMPC) formulations applied to simple nonlinear process control examples is investigated. The quasi-ARMAX predictor can be interpreted as a neuro-fuzzy predictor, and this neuro-fuzzy predictor is computationally straightforward and has showed excellent prediction capabilities. The predictor is thus well suited for NMPC purposes. Furthermore, the parameters of the neuro-fuzzy model can be argued to have explicit meaning, thus making the procedure of tuning the NMPC system more transparent when using the neuro-fuzzy predictor.

关键词： Predictive control systems

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Sanitizing proprietary manufacturing information for public presentation

Sanitizing proprietary manufacturing information for public ...

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2001 ASEE Annual Conference and Exposition: Peppers, Papers, Pueblos and Professors

作者： Chandler, Mark R. McCollom, Kathleen T. U.S. DOT FHWA Wisconsin Division Battelle Memorial Institute Technol. Transf. and Qual. Engineer Federal Highway Administration Wisconsin Division Information Systems Engineering Process Modernization Group Battelle Memorial Institute Arlington VA

A need to prepare - or sanitize - a variety of proprietary manufacturing information for public presentation may come about for a number of reasons. Typical situations requiring technical presentations include publishing a technical paper14,15,17 or a presentation at a technical conference or classroom, preparing and publishing a technical thesis in a proprietary manufacturing environment, preparing supporting material33,37 for an announcement by a company of a breakthrough in a manufacturing process, staffing a technical trade show50, applying for a Quality Award - such as the Baldrige Award, the President's Quality Award, various state Quality Awards, etc. - or preparing content for a corporate (or public agency) web site. The degree of sanitizing can range from a deferred disclosure tactic used at a technical trade show ("Why don't you give me your business card and let me give you a call back with that information after I confer with ...") to presenting proprietary manufacturing data that has been numerically modified - such as defect level numerical data improvement 'normalized' with an X-Y graph - and published in a technical journal. While a more open and complete discussion of technical details means there may be greater risk of disclosing proprietary information, doing so may achieve tangible corporate needs10,18,38 and identifiable benefits. A strategy for communicating technological advances without revealing proprietary information is suggested and outlined.

关键词： Technical presentations

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