Fully Graph Sensitivity Solution of the Switched Circuits by Two-graph

The most general parameter of the electronic circuit is its sensitivity. Sensitivity analysis helps circuit designers to determine boundaries to predict the variations that a particular design variable will generate in a target specifications, if it differs from what is previously assumed. There are two basic methods for calculating the sensitivity: matrix methods and graph methods. The method described in this article is based on a graph, that contains separate input ad output nodes for each phase. This makes it possible to determine the transmission sensitivity even between partial switching phases. The described fully-graph method is suitable for switched current circuits and switched capacitors circuits, too

Download Full-text

Study on Structure Sensitivity Analysis Using ANSYS PDS

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.1830 ◽

2011 ◽

Vol 243-249 ◽

pp. 1830-1834

Author(s):

Ke Ke Peng

Keyword(s):

Sensitivity Analysis ◽

Structure Sensitivity ◽

Design System ◽

Complex Structures ◽

Probabilistic Design ◽

Sensitivity Matrix ◽

Arch Bridge ◽

Cfst Arch Bridge ◽

Sensitive Factor ◽

Incremental Form

As to sensitivity analysis, based on traditional sensitive factor definition and concept of reliability vector, two kinds of sensitivity problems are putted forward in this paper. And factor sensitivity matrix is defined. As far as large and complex structures are concerned, factor sensitivity matrix of incremental form is given. Furthermore, sensitivity surface is putted forward. ANSYS PDS（ANSYS Probabilistic Design System）can solve the above two kinds of sensitivity problems efficiently. The example bridge is a CFST arch bridge with 83.6 meter-span, which operated for 10 years. The analysis result shows that the definitions enhance the maneuverability of sensitivity analysis, and ANSYS PDS is practical.

Download Full-text

A sensitivity analysis of DC resistivity prospecting on finite, homogeneous blocks and columns

Geophysics ◽

10.1190/1.2770537 ◽

2007 ◽

Vol 72 (6) ◽

pp. F237-F247 ◽

Cited By ~ 6

Author(s):

Qi You Zhou

Keyword(s):

Sensitivity Analysis ◽

Electric Potential ◽

Finite Size ◽

Sensitivity Matrix ◽

Subsurface Hydrology ◽

Block Boundary ◽

Scheme Design ◽

Vertical Arrays ◽

Analytic Expressions ◽

Resistivity Inversion

Besides field applications to geophysical prospecting and subsurface hydrology, electrical resistivity tomography can be applied to finite-scale blocks in the laboratory to characterize the resistivity structure of the blocks and to monitor internal physical and chemical processes. This requires a fast and accurate calculation of the sensitivity matrix to perform a successful resistivity inversion for such blocks. However, the complex geometric shape and boundary and the finite size of the block limit the application of field-suitable sensitivity calculation methods to these blocks. As blocks and finite columns are often used in the laboratory experiments, this paper develops practical analytic expressions, based on the method of image charges, for the sensitivity matrix for these two types of homogenous bodies. The corresponding formulae for the electric potential distribution and theelectrode array coefficient are also presented. As a result of the theory, the effects of placing limits on the sum index in the electric-potential calculation can be analyzed, and a comparison of the theoretical and the numerically simulated electric potential is shown. The results demonstrate the correctness of the theory and indicate that even the addition of only one set of mirror current sources greatly reduces the effects of the block boundary on the electric-potential calculation. Finally, several interesting sensitivity distributions for cross-surface arrays on blocks, and for circular and vertical arrays on columns, are given. Although the formulae developed here are only valid for homogeneous blocks and columns, and an element of relatively small volume is required to permit a good approximation to the sensitivity, the theory is useful in the verification of numerically simulated results, in sensitivity-analysis for optimum probing-scheme design, and in successful resistivity inversion calculation for finite bodies.

Download Full-text

The Perilous Use of Proxy Variables

Evaluation & the Health Professions ◽

10.1177/0163278720903358 ◽

2020 ◽

pp. 016327872090335

Author(s):

Ryan G. N. Seltzer

Keyword(s):

Sensitivity Analysis ◽

Construct Validity ◽

Design Variable ◽

Parameter Estimates ◽

Latent Constructs ◽

Proxy Variables ◽

Insufficient Amount ◽

Using Data ◽

Variable Representation ◽

Different Levels

It is often not stated or quantified how well measured proxy variables account for the variance in latent constructs they are intended to represent. A sensitivity analysis was run using data from the Survey of Health, Ageing and Retirement in Europe to estimate models varying in the degree to which proxy variables represent intended constructs. Results showed that parameter estimates differ substantially across different levels of variable representation. When variables are used with poor construct validity, an insufficient amount of variance is removed from the observed spurious relationship between design variable and outcome. The findings from this methodological demonstration underscore the importance of selecting proxy variables that accurately represent the underlying construct for which control is intended.

Download Full-text

Sensitivity Analysis: Matrix Methods in Demography and Ecology

10.1007/978-3-030-10534-1 ◽

2019 ◽

Cited By ~ 12

Author(s):

Hal Caswell

Keyword(s):

Sensitivity Analysis ◽

Matrix Methods

Download Full-text

Static, Vibration Analysis and Sensitivity Analysis of Stepped Beams Using Singularity Functions

Journal of Structures ◽

10.1155/2014/234085 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 6

Author(s):

Peng Cheng ◽

Carla Davila ◽

Gene Hou

Keyword(s):

Sensitivity Analysis ◽

Design Variable ◽

Vibration Analysis ◽

Systematic Approach ◽

Flexural Rigidity ◽

Stepped Beam ◽

Perform Sensitivity Analysis ◽

Derivation Process ◽

Related Design

A systematic approach is presented in this paper to derive the analytical deflection function of a stepped beam using singularity functions. The discontinuities considered in this development are associated with the jumps in the flexural rigidity and the applied loads. This approach is applied to static and vibration analyses of stepped beams. The same approach is later extended to perform sensitivity analysis of stepped beams. This is done by directly differentiating the analytical deflection function with respect to any beam-related design variable. The particular design variable considered here is the location of discontinuity in flexural rigidity. Example problems are presented in this paper to demonstrate and verify the derivation process.

Download Full-text

Sensitivity Analysis and Optimization of Undamped Rotor Critical Speeds to Supports Stiffness

Journal of Vibration and Acoustics ◽

10.1115/1.1456083 ◽

2002 ◽

Vol 124 (2) ◽

pp. 296-301 ◽

Cited By ~ 12

Author(s):

Shyh-Chin Huang ◽

Chin-Ann Lin

Keyword(s):

Sensitivity Analysis ◽

Solution Process ◽

Optimal Solution ◽

Frequency Equation ◽

Sensitivity Matrix ◽

Variable Metric ◽

Critical Speeds ◽

Rotor Design ◽

Receptance Method ◽

Variable Metric Method

This paper introduced a new approach that employed the assumed-modes method and the receptance method, to the sensitivity analysis and the optimization of rotor-bearing systems. First, the frequency equation in terms of receptances was derived. The natural frequencies and the critical speeds for a typical rotor system were then illustrated. Beginning with the receptance equation, the authors, for the first time, derived a sensitivity matrix and employed it into an optimization process. The topographical method in conjunction with the variable metric method followed for the optimal solution. In the solution process, the sensitivity matrix provided important information for search direction. Examples of critical speeds adjustment via supports change in an optimal sense were illustrated. Numerical results showed that the approach was very efficient and the solutions were very accurate. This approach, in addition, provided such valuable information as which supports dominated specific critical speeds. The developed approach proved to be very helpful to rotor engineers in both rotor modification and rotor design.

Download Full-text

Direct and Inverse Problems for a Fourth Order Anomalous Diffusion Model

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.399.55 ◽

2020 ◽

Vol 399 ◽

pp. 55-64

Author(s):

Jader Lugon Junior ◽

Luiz Bevilacqua ◽

Antônio José da Silva Neto

Keyword(s):

Inverse Problem ◽

Sensitivity Analysis ◽

Diffusion Model ◽

Fourth Order ◽

Anomalous Diffusion ◽

Equation Model ◽

Order Equation ◽

Sigmoid Function ◽

Sensitivity Matrix ◽

Fractional Equations

The second order equation (also known as Fick’s equation) is derived from a classical well-known theory, but it is not enough to model all applications of interest. Recently, fractional equations and higher order equations began to receive more attention, demanding increased research efforts. They are used to simulate the diffusion process in many important applications in sciences, such as chemistry, heat and mass transfer, biology and ecology. In this work, the sensitivity analysis is performed for a recently developed anomalous diffusion model in order to evaluate the possibility of estimating a set of parameters that are part of the fourth order equation model, including the parameters representing the variation of the fraction of particles that are allowed to diffuse using a sigmoid function. Finally, after the sensitivity analysis the Inverse Problem approach is used to estimate viable parameters that are necessary for simulation in the cases considered. The differential equation was approximated using the Finite Difference Method, and that solution was implemented in the RStudio platform. The Sensitivity Matrix was calculated and the Inverse Problem was solved using the same RStudio platform, and the Simulated Annealing Method.

Download Full-text