Design parameters and sensitivity analysis of polymer-cladded porous silicon waveguides for small molecule detection

2010 ◽  
Vol 25 (6) ◽  
pp. 1535-1538 ◽  
Author(s):  
Yang Jiao ◽  
Sharon M. Weiss
Keyword(s):  
Sensitivity Analysis ◽  
Porous Silicon ◽  
Small Molecule ◽  
Design Parameters ◽  
Silicon Waveguides ◽  
Small Molecule Detection

Grating Coupled Waveguide Biosensor Based on Porous Silicon

2011 ◽  
Vol 1301 ◽  
Author(s):  
Xing Wei ◽  
Sharon M. Weiss
Keyword(s):  
Electron Beam ◽  
Porous Silicon ◽  
Nucleic Acids ◽  
Surface Area ◽  
Small Molecule ◽  
Electron Beam Lithography ◽  
Low Cost ◽  
Grating Couplers ◽  
Silicon Waveguides ◽  
A New Technique

ABSTRACTPorous silicon waveguides with integrated porous silicon grating couplers are demonstrated as small molecule biosensors. Two fabrication methods are presented for the grating couplers: standard electron beam lithography with reactive ion etching and a new technique based on direct imprinting of porous substrates. Although the gratings fabricated using standard lithographic techniques have steeper sidewalls and enable a larger available sensing surface area inside the waveguide, the imprinted gratings have the advantage of rapid and low-cost fabrication. Both the lithographically and imprinted sensors are shown to have waveguide losses on the order of 10 dB/cm, and both are demonstrated for detection of 16mer nucleic acids.

A fluorescent porous silicon-based biosensor for small molecule detection

2016 ◽  
Vol 12 (6) ◽  
pp. 478-480 ◽  
Author(s):  
Xiao-yi Lü ◽  
Guo-dong Lü ◽  
Jia-qing Mo ◽  
Liang Xu ◽  
Zhen-hong Jia
Keyword(s):  
Porous Silicon ◽  
Small Molecule ◽  
Small Molecule Detection ◽  
Silicon Based

Development of a Porous Silicon Product for Small Molecule Mass Spectrometry

2004 ◽  
Vol 808 ◽  
Author(s):  
Grace Credo ◽  
Hillary Hewitson ◽  
Christopher Benevides ◽  
Edouard S. P. Bouvier
Keyword(s):  
Mass Spectrometry ◽  
Porous Silicon ◽  
Small Molecule ◽  
Dynamic Range ◽  
Peptide Identification ◽  
High Sensitivity ◽  
Flight Mass Spectrometry ◽  
Protein Digests ◽  
Potential Applications ◽  
Small Molecule Detection

ABSTRACTPrevious work has demonstrated the utility of desorption/ionization on silicon (DIOS) time-of-flight mass spectrometry (TOFMS) in drug molecule and peptide detection[1-7]. In this work, the utility of DIOS for small molecule detection is established using commercially available porous silicon (por Si)-based target plates for MS. Since the morphology and handling of the substrates can have dramatic effects on the MS characteristics, the development of consistent manufacturing methods and characterization protocols has been central to the production of reproducible target plates[7]. Using sample substrates manufactured in-house, we show that 1) small molecules and protein digests were detected without matrix-related peaks, 2) por Si morphology was optimized for small molecule detection, 3) reproducible DIOS plates were produced, 4) although the target plates were shown to be sensitive to contamination, a consistent cleaning procedure was developed to remove contaminants, and 5) stability and shelf life were characterized as a function of surface derivatization. Dynamic range, sensitivity, quantitation, speed of analysis, solution composition, and automated deposition have also been evaluated and are described in related work[7-9]. Potential applications include high-throughput small molecule assays for drug discovery[10a] and high sensitivity (sub-femtomole) peptide identification for proteomics[10b].

scholarly journals CONCEPTUAL DESIGN FOR ASSEMBLY IN AEROSPACE INDUSTRY: SENSITIVITY ANALYSIS OF MATHEMATICAL FRAMEWORK AND DESIGN PARAMETERS

2021 ◽  
Vol 1 ◽  
pp. 731-740
Author(s):  
Giovanni Formentini ◽  
Claudio Favi ◽  
Claude Cuiller ◽  
Pierre-Eric Dereux ◽  
Francois Bouissiere ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Conceptual Design ◽  
Design Parameters ◽  
Design For Assembly ◽  
Mathematical Framework ◽  
Commercial Aircraft ◽  
System Architectures ◽  
Complex Engineering ◽  
Aircraft System ◽  
Definition Of

AbstractOne of the most challenging activity in the engineering design process is the definition of a framework (model and parameters) for the characterization of specific processes such as installation and assembly. Aircraft system architectures are complex structures used to understand relation among elements (modules) inside an aircraft and its evaluation is one of the first activity since the conceptual design. The assessment of aircraft architectures, from the assembly perspective, requires parameter identification as well as the definition of the overall analysis framework (i.e., mathematical models, equations).The paper aims at the analysis of a mathematical framework (structure, equations and parameters) developed to assess the fit for assembly performances of aircraft system architectures by the mean of sensitivity analysis (One-Factor-At-Time method). The sensitivity analysis was performed on a complex engineering framework, i.e. the Conceptual Design for Assembly (CDfA) methodology, which is characterized by level, domains and attributes (parameters). A commercial aircraft cabin system was used as a case study to understand the use of different mathematical operators as well as the way to cluster attributes.

Direct Sensitivity Analysis of Spatial Multibody Systems With Joint Friction Using Index-1 Formulation

2021 ◽  
Author(s):  
Adwait Verulkar ◽  
Corina Sandu ◽  
Daniel Dopico ◽  
Adrian Sandu
Keyword(s):  
Sensitivity Analysis ◽  
Dynamic Systems ◽  
Multibody Systems ◽  
Friction Model ◽  
Design Parameters ◽  
Adjoint Sensitivity ◽  
Joint Friction ◽  
Multibody Dynamic ◽  
Model Dynamics ◽  
Direct Sensitivity

Abstract Sensitivity analysis is one of the most prominent gradient based optimization techniques for mechanical systems. Model sensitivities are the derivatives of the generalized coordinates defining the motion of the system in time with respect to the system design parameters. These sensitivities can be calculated using finite differences, but the accuracy and computational inefficiency of this method limits its use. Hence, the methodologies of direct and adjoint sensitivity analysis have gained prominence. Recent research has presented computationally efficient methodologies for both direct and adjoint sensitivity analysis of complex multibody dynamic systems. The contribution of this article is in the development of the mathematical framework for conducting the direct sensitivity analysis of multibody dynamic systems with joint friction using the index-1 formulation. For modeling friction in multibody systems, the Brown and McPhee friction model has been used. This model incorporates the effects of both static and dynamic friction on the model dynamics. A case study has been conducted on a spatial slider-crank mechanism to illustrate the application of this methodology to real-world systems. Using computer models, with and without joint friction, effect of friction on the dynamics and model sensitivities has been demonstrated. The sensitivities of slider velocity have been computed with respect to the design parameters of crank length, rod length, and the parameters defining the friction model. Due to the highly non-linear nature of friction, the model dynamics are more sensitive during the transition phases, where the friction coefficient changes from static to dynamic and vice versa.

Direct Sensitivity Analysis of Multibody Systems: A Vehicle Dynamics Benchmark

2019 ◽  
Vol 14 (2) ◽  
Author(s):  
Alfonso Callejo ◽  
Daniel Dopico
Keyword(s):  
Sensitivity Analysis ◽  
Multibody Systems ◽  
Automatic Differentiation ◽  
Time Integration ◽  
General Purpose ◽  
Contact Forces ◽  
Design Parameters ◽  
Computational Techniques ◽  
Computationally Efficient ◽  
Integration Algorithm

Algorithms for the sensitivity analysis of multibody systems are quickly maturing as computational and software resources grow. Indeed, the area has made substantial progress since the first academic methods and examples were developed. Today, sensitivity analysis tools aimed at gradient-based design optimization are required to be as computationally efficient and scalable as possible. This paper presents extensive verification of one of the most popular sensitivity analysis techniques, namely the direct differentiation method (DDM). Usage of such method is recommended when the number of design parameters relative to the number of outputs is small and when the time integration algorithm is sensitive to accumulation errors. Verification is hereby accomplished through two radically different computational techniques, namely manual differentiation and automatic differentiation, which are used to compute the necessary partial derivatives. Experiments are conducted on an 18-degree-of-freedom, 366-dependent-coordinate bus model with realistic geometry and tire contact forces, which constitutes an unusually large system within general-purpose sensitivity analysis of multibody systems. The results are in good agreement; the manual technique provides shorter runtimes, whereas the automatic differentiation technique is easier to implement. The presented results highlight the potential of manual and automatic differentiation approaches within general-purpose simulation packages, and the importance of formulation benchmarking.

Design Sensitivity Analysis of Nonlinear Multidisciplinary Multibody Systems in the MIXEDMODELS Platform

2007 ◽  
Author(s):  
Shilpa A. Vaze ◽  
Prakash Krishnaswami ◽  
James DeVault
Keyword(s):  
Sensitivity Analysis ◽  
Multibody Systems ◽  
Design Sensitivity ◽  
Differential Algebraic Equations ◽  
The State ◽  
Design Sensitivity Analysis ◽  
Design Parameters ◽  
State Variables ◽  
Sensitivity Coefficients ◽  
Design Variables

Most state-of-the-art multibody systems are multidisciplinary and encompass a wide range of components from various domains such as electrical, mechanical, hydraulic, pneumatic, etc. The design considerations and design parameters of the system can come from any of these domains or from a combination of these domains. In order to perform analytical design sensitivity analysis on a multidisciplinary system (MDS), we first need a uniform modeling approach for this class of systems to obtain a unified mathematical model of the system. Based on this model, we can derive a unified formulation for design sensitivity analysis. In this paper, we present a modeling and design sensitivity formulation for MDS that has been successfully implemented in the MIXEDMODELS (Multidisciplinary Integrated eXtensible Engine for Driving Metamodeling, Optimization and DEsign of Large-scale Systems) platform. MIXEDMODELS is a unified analysis and design tool for MDS that is based on a procedural, symbolic-numeric architecture. This architecture allows any engineer to add components in his/her domain of expertise to the platform in a modular fashion. The symbolic engine in the MIXEDMODELS platform synthesizes the system governing equations as a unified set of non-linear differential-algebraic equations (DAE’s). These equations can then be differentiated with respect to design to obtain an additional set of DAE’s in the sensitivity coefficients of the system state variables with respect to the system’s design variables. This combined set of DAE’s can be solved numerically to obtain the solution for the state variables and state sensitivity coefficients of the system. Finally, knowing the system performance functions, we can calculate the design sensitivity coefficients of these performance functions by using the values of the state variables and state sensitivity coefficients obtained from the DAE’s. In this work we use the direct differentiation approach for sensitivity analysis, as opposed to the adjoint variable approach, for ease in error control and software implementation. The capabilities and performance of the proposed design sensitivity analysis formulation are demonstrated through a numerical example consisting of an AC rectified DC power supply driving a slider crank mechanism. In this case, the performance functions and design variables come from both electrical and mechanical domains. The results obtained were verified by perturbation analysis, and the method was shown to be very accurate and computationally viable.

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