Preface |
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xiii | |
Author |
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xv | |
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1 Introduction to Lagrange optimization for engineering applications |
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1 | (26) |
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1.1 Significance of this chapter |
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1 | (1) |
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1.2 An optimality formulation based on equality constraints |
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2 | (4) |
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1.2.1 Formulation of Lagrange functions |
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2 | (1) |
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1.2.2 Formulation of gradient vectors |
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2 | (2) |
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1.2.3 Optimality conditions of objective functions constrained by equality functions based on gradient vectors; finding stationary points based on gradients vectors |
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4 | (1) |
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1.2.4 Optimizations of an objective function constrained by equality functions |
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5 | (1) |
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1.3 An optimality formulation based on inequality constraints |
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6 | (18) |
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1.3.1 KKT (Karush-Kuhn-Tucker Conditions) optimality conditions |
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6 | (2) |
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1.3.2 Formulation of KKT optimality conditions (active and inactive), their implications on economy and structural engineering |
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8 | (1) |
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1.3.3 Optimality examples with inequality conditions |
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9 | (1) |
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9 | (5) |
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14 | (1) |
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14 | (5) |
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19 | (5) |
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1.4 How many KKT conditions (Kuhn and Tucker, 1951; Kuhn and Tucker, 2014) must be considered? |
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24 | (1) |
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25 | (2) |
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25 | (2) |
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2 Lagrange optimization using artificial neural network-based generalized functions |
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27 | (172) |
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2.1 Importance of an optimization for engineering designs |
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27 | (1) |
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2.1.1 Significance of ANN-based optimization |
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27 | (1) |
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2.1.2 Why ANN-based generalized functions? |
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28 | (1) |
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2.2 ANN-based Lagrange formulation constrained by inequality functions |
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28 | (1) |
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2.3 ANN-based generalizable objective and constraining functions |
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29 | (23) |
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2.3.1 A [ imitation of an analytical function-based objective and inequality functions |
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29 | (1) |
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2.3.2 Formulation of ANN-based Lagrange functions and KKT condition |
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29 | (1) |
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2.3.3 Formulation of ANN-based objective and inequality functions |
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30 | (2) |
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2.3.4 Linear approximation of a first derivative (Jacobi) of Lagrange functions |
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32 | (1) |
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2.3.4.1 Optimization based on linearized Lagrange functions based on first-order (Jacobian matrix δ £(x(k), λc(k), λv(k))4% using Newton-Raphson iteration |
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32 | (3) |
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2.3.4.2 Formulation of generalized Jacobian and Hessian matrices |
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35 | (4) |
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2.3.4.3 Formulation of KKT non-linear equations based on Newton-Raphson iteration |
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39 | (1) |
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2.3.5 Stationary points of Lagrange functions based on gradient vectors |
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39 | (1) |
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2.3.6 ANN-based generalized functions replacing analytical functions |
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40 | (1) |
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2.3.6.1 Formulation of Jacobian and Hessian matrices |
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40 | (2) |
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2.3.6.2 Formulation of Jacobian matrix based on ANN |
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42 | (3) |
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2.3.6.3 Formulation of universally generalizable Hessian matrix based on ANN |
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45 | (6) |
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2.3.6.4 Flow chart for Lagrange-based optimization |
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51 | (1) |
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52 | (1) |
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2.4 Examples of optimizing Lagrange functions using ANN-based objective and constraining functions with KKT conditions |
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52 | (147) |
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2.4.1 Purpose of examples |
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52 | (1) |
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2.4.2 Optimization of a fourth-order polynomial with KKT conditions |
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53 | (1) |
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2.4.2.1 Optimization of a fourth-order polynomial considering inequality constraints based on analytical objective and constraining functions |
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53 | (9) |
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2.4.2.2 ANN-based optimization of a fourth-order polynomial constrained by inequality functions |
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62 | (15) |
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77 | (1) |
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2.4.3 A design of a truss frame based on Lagrange optimization |
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78 | (1) |
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2.4.3.1 Lagrange optimization of a truss frame based on analytical objective and constraining functions |
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78 | (18) |
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2.4.3.2 Lagrange optimization of a truss frame based on ANN-based object and constraining functions |
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96 | (46) |
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142 | (2) |
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2.4.4 Maximizing flying distance of a projectile based on Lagrange optimization |
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144 | (1) |
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2.4.4.1 Analytical function-based Lagrange optimization |
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144 | (16) |
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2.4.4.2 ANN-based Lagrange optimization |
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160 | (38) |
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198 | (1) |
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3 Design of reinforced concrete columns using ANN-based Lagrange algorithm |
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199 | (110) |
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199 | (2) |
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3.1.1 Overview of Lagrange multiplier method-based KKT conditions |
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199 | (1) |
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3.1.2 Optimization implemented in structural engineering |
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200 | (1) |
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3.1.3 Significance of the chapter |
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201 | (1) |
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3.2 ANN-based on Lagrange networks |
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201 | (23) |
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3.2.1 Obtaining minimum design parameters for reinforced concrete columns based on ACI318-19 and ACI318-19 |
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202 | (1) |
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3.2.2 ANN-based functions including objective functions of RC columns |
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203 | (1) |
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3.2.2.1 Weight and bias matrices based on forward ANNs to derive objective functions |
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203 | (15) |
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3.2.2.2 Weight and bias matrices based on reverse ANNs to derive objective functions |
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218 | (1) |
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3.2.2.3 Jacobian and Hessian matrices derived based on ANNs |
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218 | (3) |
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3.2.2.4 Stationary points of Lagrange functions C(x, Xc, Xy) subject to constraining conditions based on Newton-Raphson iteration |
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221 | (3) |
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3.3 Optimization of column designs based on an Ann-based Lagrange algorithm |
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224 | (78) |
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3.3.1 Column design scenario minimizing CIc |
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225 | (1) |
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3.3.1.1 Formulation of Lagrange optimization based on forward network |
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225 | (14) |
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3.3.1.2 Formulation of Lagrange optimization based on a reverse network |
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239 | (8) |
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247 | (8) |
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255 | (1) |
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3.3.2 Column design scenario minimizing COz |
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255 | (1) |
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3.3.2.1 Formulation of forward network vs. reverse network |
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255 | (2) |
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3.3.2.2 Solving KKT nonlinear equations based on Newton-Raphson iteration |
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257 | (17) |
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274 | (3) |
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277 | (1) |
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3.3.3 Column design scenario minimizing weight |
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278 | (1) |
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3.3.3.1 Formulation of forward network vs. reverse network |
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278 | (1) |
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3.3.3.2 Solving KKT nonlinear equations based on Newton-Raphson method |
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279 | (19) |
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298 | (1) |
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299 | (2) |
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3.3.3.5 Influence of optimization on P-M diagrams |
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301 | (1) |
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3.4 Noticeable updates with ACI 318-19 compared with 318-14 |
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302 | (2) |
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304 | (5) |
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306 | (3) |
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4 Optimization of a reinforced concrete beam design using ANN-based Lagrange algorithm |
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309 | (38) |
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4.1 Significance of the Chapter |
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309 | (2) |
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309 | (1) |
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4.1.2 Motivations and objective |
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310 | (1) |
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4.1.3 Significance of the proposed methodology |
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310 | (1) |
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4.2 Optimization of a reinforced concrete beam designs based on ANNs |
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311 | (10) |
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4.2.1 Beam design scenarios |
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311 | (2) |
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4.2.2 Formulation of a Lagrange function for optimizing a reinforced concrete beam based on ANNs |
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313 | (1) |
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4.2.2.1 Derivation of ANN-based objective functions |
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313 | (3) |
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4.2.2.2 Derivation of ANN-based Lagrange functions |
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316 | (1) |
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4.2.2.3 Formulation of KKT conditions based on equality and inequality constraints |
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317 | (4) |
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4.3 Generation of Large Structural Datasets |
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321 | (5) |
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4.3.1 Input and output parameters selected for large datasets |
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321 | (1) |
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4.3.2 Random design ranges |
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321 | (1) |
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4.3.3 Network training based on parallel training method (PTM) training |
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322 | (1) |
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4.3.4 Training for forward Lagrange networks |
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322 | (1) |
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4.3.5 Training for rebar placements with multiple layers |
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323 | (3) |
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326 | (6) |
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4.4.1 Verification of design parameters based on a forward Lagrange network |
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326 | (4) |
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4.4.2 Verification of Selected parameters based on large datasets |
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330 | (1) |
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4.4.3 Cost savings based on Lagrange algorithm |
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331 | (1) |
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4.5 Design Charts Based on ANN-Based Lagrange Optimizations Minimizing CIb |
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332 | (6) |
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4.5.1 Optimization of the cost (CIJ for material and manufacture for design ductile beam sections based on design charts |
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331 | (4) |
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4.5.2 Use of design charts to design ductile beam sections |
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335 | (2) |
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4.5.3 Verification of optimization |
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337 | (1) |
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4.6 Use of ANN-Based Lagrange Networks to Investigate Changes between ACI 318-14 and ACI 318-19 |
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338 | (3) |
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338 | (1) |
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4.6.1.1 Revised limit of tension-controlled sections |
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338 | (1) |
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4.6.1.2 Reduction in effective moment of inertia for ACI318-19 |
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338 | (2) |
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4.6.2 The Comparisons between ACI 318-14 and ACI 318-19 Based on Conventional Structural Calculations |
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340 | (1) |
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4.6.3 Changes of Optimized Results between ACI 318-14 and ACI 318-19 Using ANNs |
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341 | (1) |
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4.7 Results and Discussions |
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341 | (2) |
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4.7.1 ANN-based formulation of objective functions |
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341 | (1) |
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4.7.2 Design charts obtained based on Lagrange networks optimizing cost (material and manufacture) of ductile doubly reinforced concrete beams |
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342 | (1) |
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4.7.3 Verifying optimized objective functions |
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343 | (1) |
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4.7.4 ANN-based structural designs beyond human efficiency |
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343 | (1) |
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343 | (4) |
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344 | (3) |
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5 ANN-based structural designs using Lagrange multipliers optimizing multiple objective functions |
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347 | (141) |
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347 | (19) |
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5.1.1 Significance of optimizing multiple objective functions |
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347 | (1) |
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347 | (1) |
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5.1.1.2 Problem Descriptions and Motivations of the Chapter |
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348 | (1) |
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5.1.1.3 Significance of optimizing UFOs |
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349 | (1) |
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5.1.1.4 Contents of Chapter 5 |
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350 | (1) |
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5.1.2 Review of Pareto frontier |
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350 | (4) |
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5.1.3 Criterion space and Pareto frontier |
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354 | (1) |
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5.1.4 Weighted sum method |
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355 | (1) |
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5.1.4.1 The first method - minimization of bi-objective functions based on a definition of nondominated points |
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356 | (2) |
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5.1.4.2 The second method - minimizing bi-objective functions (UFO) based on weighted sum method |
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358 | (4) |
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5.1.5 Normalized unified function of objectives implementing weighted sum method |
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362 | (1) |
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5.1.5.1 Normalized UFOs implementing weighted sum method |
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362 | (2) |
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5.1.5.2 Discussion on normalized objective and nonnormalized functions |
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364 | (2) |
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5.2 ANN-based Lagrange functions optimizing multiple objective functions |
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366 | (5) |
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5.2.1 Significance of considering UFO |
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366 | (1) |
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5.2.2 Unified function of objectives |
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367 | (1) |
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5.2.3 ANN-based Lagrange optimization algorithm of five steps based on UFO |
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368 | (3) |
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5.3 ANN-based Lagrange optimization design of RC circular columns having multiple objective |
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371 | (30) |
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5.3.1 Forward design of circular RC columns |
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372 | (1) |
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5.3.2 Optimization design scenarios |
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373 | (1) |
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5.3.3 Five steps to optimize circular RC column based on three-objective functions |
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373 | (11) |
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5.3.4 Discussions on an optimization based on three objective functions |
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384 | (1) |
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5.3.5 Verification to large datasets |
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384 | (1) |
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5.3.6 Generation of evenly spaced fractions |
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385 | (5) |
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5.3.7 Interpretation of data trend |
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390 | (1) |
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5.3.7.1 Relationships among three objective functions |
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390 | (1) |
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5.3.7.2 Exploring trend of large datasets |
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391 | (2) |
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5.3.8 Examples of optimal designs based on Pareto frontier |
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393 | (1) |
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5.3.8.1 Identifying design parameters for a designated fraction |
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393 | (5) |
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5.3.8.2 Optimized P-M diagram |
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398 | (1) |
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5.3.9 Decision-making based on Pareto frontier |
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399 | (2) |
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5.4 An ANN-based optimization of UFO for circular RC columns sustaining multiple loads |
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401 | (26) |
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5.4.1 Reusing components of weight matrices subject to one biaxial load pair (ANN-1LP) to derive weight matrices subject to multiple biaxial load pairs (ANN-nLP) load pairs |
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401 | (3) |
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5.4.1.1 Generalized ANN (Model-LPs) used to derive n load pairs (Tu MUii) |
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404 | (2) |
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5.4.1.2 Formulation of the Network subject to multi-load pairs |
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406 | (16) |
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5.4.2 An optimization of a circular RC column sustaining five load pairs based on three-objective functions |
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422 | (1) |
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5.4.2.1 Optimization design scenario |
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422 | (1) |
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5.4.2.2 Five steps to optimize a circular RC column sustaining five load pairs based on three-objective functions |
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422 | (4) |
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5.4.3 Verification of Pareto frontier based on large datasets |
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426 | (1) |
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5.5 ANN-based Lagrange optimization for UFO to design uniaxial rectangular RC columns sustaining multiple loads |
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427 | (11) |
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5.5.1 Optimization scenario based on a forward design |
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427 | (1) |
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5.5.2 Five-step optimization based on multiple objective functions |
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428 | (5) |
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5.5.3 Verification of Pareto frontier to large dataset |
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433 | (1) |
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5.5.4 Design parameters corresponding to three fractions of Pareto frontier |
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433 | (5) |
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5.6 ANN-based Lagrange optimization for UFO to design biaxial rectangular RC columns sustaining multiple loads |
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438 | (23) |
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5.6.1 Optimization scenario based on a forward design subject to multi-loads with small magnitude |
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438 | (1) |
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5.6.2 Five steps optimization based on multiple objective functions |
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439 | (6) |
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5.6.3 Verification of Pareto frontier based on large datasets |
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445 | (1) |
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5.6.4 Design parameters corresponding to three points of Pareto frontier |
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445 | (2) |
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5.6.5 An example of ANN-based Lagrange optimization design based on multi-objective functions for biaxial rectangular RC columns sustaining multiple loads with big magnitude |
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447 | (1) |
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5.6.5.1 Identifying design parameters for designated fractions based on two neural networks based on Tables 5.6.2.3 and 5.6.5.6 |
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448 | (10) |
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5.6.5.2 Design accuracies based on the two neural networks based on Tables 5.6.2.3 and 5.6.5.6 for the two Pareto curves |
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458 | (3) |
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5.7 ANN-based Lagrange multi-objective optimization design of RC beams |
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461 | (23) |
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5.7.1 Design scenarios of doubly reinforced concrete beams |
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462 | (1) |
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5.7.1.1 Selection of design parameters based on design criteria of doubly reinforced concrete beams |
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462 | (2) |
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5.7.1.2 Selection of objective functions |
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464 | (1) |
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5.7.1.3 An optimization scenario |
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464 | (2) |
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5.7.2 Five steps to optimize a design of RC beams with which Clb, C02 and Wb are minimized |
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466 | (2) |
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5.7.2.1 Step 1-Deriving ANNs |
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468 | (3) |
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5.7.2.2 Step 2-Defining MOO problems |
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471 | (2) |
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5.7.2.3 Step 3-Optimization based on a single-objective function |
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473 | (1) |
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5.7.2.4 Step 4-Formulating UFO |
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473 | (1) |
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5.7.2.5 Step 5-Optimizing UFO |
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474 | (1) |
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5.7.3 Design parameters corresponding to various fractions on Pareto frontier |
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474 | (3) |
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5.7.4 Verification of Pareto frontier |
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477 | (3) |
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5.7.5 Decision-making based on the Pareto frontier |
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480 | (3) |
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5.7.6 Interpretation of data trend based on relationships among three objective functions |
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483 | (1) |
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5.8 Design recommendations and conclusions |
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484 | (4) |
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5.8.1 Design recommendations |
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484 | (1) |
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484 | (1) |
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485 | (3) |
Acknowledgments |
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488 | (1) |
Appendix A |
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489 | (22) |
Appendix B |
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511 | (8) |
Appendix C |
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519 | (18) |
Appendix D |
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537 | (24) |
Index |
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561 | |