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- <p>Dynamic programming<br />Adaptive control systems -- Mathematical models<br />Nonlinear systems -- Mathematical models<br />Neural networks (Computer science)</p> (1)
- <p>Forging machinery -- Mathematical models<br />Founding -- Defects -- Mathematical models<br />Nonlinear mechanics<br />Finite element method</p> (1)
- <p>Sandwich construction<br />Heat -- Transmission -- Analysis<br />Structural stability -- Mathematical models</p> (1)
- <p>Vibration -- Mathematical models<br />Internal combustion engines -- Combustion -- Testing<br />Oscillations</p> (1)
- <p>Vibration -- Physiological effect -- Computer simulation<br />Vibration -- Measurement -- Computer simulation<br />Human engineering -- Computer simulation<br />Robotics -- Human factors<br />State-space methods</p> (1)
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- Detectors -- Design and construction<br />Femtosecond lasers<br />Micromachining<br />Silicon -- Surfaces (1)
- Homogeneous charge compression ignition (HCCI) (1)
- Honeycomb structures -- Materials -- Testing<br />Composite materials<br />Manufacturing processes (1)
- Stepped facings (1)
- Vacuum assisted resin transfer molding (VARTM) (1)
Articles 1 - 7 of 7
Full-Text Articles in Mechanical Engineering
Advanced Composites Using Non-Autoclave Processes: Manufacturing And Characterization, V. G. K. Menta
Advanced Composites Using Non-Autoclave Processes: Manufacturing And Characterization, V. G. K. Menta
Doctoral Dissertations
"The objective of the present study is to develop non-autoclave processes to manufacture high performance composites for aerospace applications. In Paper 1, vacuum assisted resin transfer molding (VARTM) process was developed for elevated temperature composites. Use of VARTM process for fabricating high temperature resins presents unique challenges such as high porosity and low fiber volume contents. Two different vacuum bagging methods: Seeman Composite Resin Infusion Molding Process (SCRIMP) and Double Vacuum Bagging Infusion (DVBI) process were evaluated. Flow simulation tool was used to predict key flow parameters needed for the successful infusion. In Paper 2, honeycomb sandwich panels were manufactured …
Sandwich Structures With Advanced Facings, Cody H. Nguyen
Sandwich Structures With Advanced Facings, Cody H. Nguyen
Doctoral Dissertations
"The purpose of this research is to investigate potential advantages of two innovative designs of sandwich panels. The first design involves sandwich panels with a piece-wise thickness of the facings aiming at two possible outcomes: (I) improved the structural response, i.e. strength and stiffness, without increasing the weight of the structure or (2) reduction in the weight of the structure without a detriment to its structural response. The analysis is conducted analytically using the first-order shear deformation theory and numerically by the finite element analysis of conventional and stepped-wise sandwich panels. The applicability of the first-order shear deformation theory to …
Femtosecond Laser Micromachining Of Microstructures For Sensing And Detection, Yukun Han
Femtosecond Laser Micromachining Of Microstructures For Sensing And Detection, Yukun Han
Doctoral Dissertations
"This thesis focuses on the fabrication and analysis of miniature functional devices that can be used for different sensing and detection applications. As the first step, the surface characteristics and morphology of the micro/nano structures on substrates (fused silica and silicon) fabricated in water and in air by femtosecond laser were investigated. Based on this study, three micro devices have been designed and fabricated by femtosecond laser, and they were analyzed for optical and chemical sensing and detections. The three micro devices are: 1) an optical Fabry-Perot interferometer in optical fiber (made from fused silica) with smooth cavity surfaces. The …
Approximate Dynamic Programming Solutions With A Single Network Adaptive Critic For A Class Of Nonlinear Systems, Jie Ding
Doctoral Dissertations
"Approximate dynamic programming formulation implemented with an Adaptive Critic (AC) based neural network (NN) structure has evolved as a powerful technique for solving the Hamilton-Jacobi-Bellman (HJB) equations. As interest in ADP and the AC solutions are escalating with time, there is a dire need to consider possible enabling factors for their implementations. A typical AC structure consists of two interacting NNs which is computationally expensive. In this work, a new architecture, called the "Cost Function Based Single Network Adaptive Critic (J-SNAC)" is presented that eliminates one of the networks in a typical AC structure. This approach is applicable to a …
Nonlinear Modeling And Simulation Of Radial Forging Process, Jian Chen
Nonlinear Modeling And Simulation Of Radial Forging Process, Jian Chen
Doctoral Dissertations
"Radial forging is an important manufacturing process to produce large cannon barrels. It is used to improve the material properties and reduce the porosity of the billet. The objective of this study is to develop finite element models to investigate the behavior of the workpiece and predict the elimination of void defects in the radial forging process. A nonlinear coupled finite element model has been developed to study the behavior of a large-diameter tube subjected to mechanical and thermal loadings in hot radial forging. The model is formulated in a three-dimensional frame, accounting for both axial and circumferential effects. A …
Development Of A Simple Vibration Model For Predicting The Structural Dynamics Of An Hcci Engine, Jeffery A. Massey
Development Of A Simple Vibration Model For Predicting The Structural Dynamics Of An Hcci Engine, Jeffery A. Massey
Doctoral Dissertations
"The hypothesis tested in this work is that the surface vibration and radiated sound of an engine operating under HCCI combustion is dominated by the free vibration response of the engine's structural components to an impulsive loading brought about by the rapid energy release of the HCCI combustion process. Recent work by the author has shown that classical vibration theory describing the dynamic response of a single-degree-of-freedom (SDOF) oscillator may capture the major characteristics of the engine surface vibrations. Through an experimental investigation of HCCI combustion engine dynamics this model has been developed further.
A band level analysis of measured …
Dynamic Ergonomic Analysis And Simulation Of Fastening Operation, Akul Joshi
Dynamic Ergonomic Analysis And Simulation Of Fastening Operation, Akul Joshi
Doctoral Dissertations
"Operator performing fastening operation with powered hand-tools at awkward postures is subjected to external forces that may pose a risk of developing ergonomic injuries. For design of safe workplaces and selection of tools it is necessary to identify the probable causes of discomfort by simulating the work conditions and quantifying the risk factors. An ergonomic simulator is developed to simulate the fastening operation and quantify the effects of posture and force in fastening operation. The effect of dynamic forces is analyzed using two approaches. The first approach analyzes the effect of tool vibration while the second analyzes the hand-arm system …