With the continuous optimization of prefabricated concrete structures, they have been widely used in the field of construction. However, due to the existence of semi-rigid connections in prefabricated concrete structu...
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With the continuous optimization of prefabricated concrete structures, they have been widely used in the field of construction. However, due to the existence of semi-rigid connections in prefabricated concrete structures, the seismic performance of the entire structure will be reduced. Therefore, how to improve the seismic performance of prefabricated concrete structures has become a current research hotspot. This study first combines interlayer isolation structures with prefabricated concrete to build a new type of semi-rigid connection prefabricated concrete interlayer isolation system. Then, to further optimize the seismic simulation performance of the system, a multi-objective optimization scheme of semi-rigid connection prefabricated concrete interlayer isolation structure is designed by combining the sequential quadratic programming algorithm and the interior point method. The research results indicate that the multi-objective optimization algorithm used has good optimization performance. The cost optimization accuracy under this algorithm can reach up to 0.98, and in addition, the displacement and acceleration objective function values under this algorithm can also be maintained at around 0.95. In summary, the multi-objective optimization algorithm proposed by this research institute has good optimization results, which can ensure that the building structure has good seismic performance while meeting the optimal cost, displacement, and acceleration objective function values.
Hybrid energy systems are an important part of sustainable development. Due to increased interest in optimal using of these systems, having various methods to solve the optimization problem seems to be necessary. This...
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ISBN:
(纸本)9781665419574
Hybrid energy systems are an important part of sustainable development. Due to increased interest in optimal using of these systems, having various methods to solve the optimization problem seems to be necessary. This paper proposes a two-layer algorithm to use in a multi-objective optimization of the hybrid energy system planning. In the first layer, the optimal sizes of the hybrid power supply components are calculated by using moth-flame optimization algorithm (MFO). In the second layer, the optimal power flow is calculated by using the mathematical quadratic programming algorithm (QP) to optimize the hybrid energy system operation. Then, it is possible to prioritize the goals and add the extra constraints, by weighting coefficients. The optimization results have been compared to show the effectiveness of the proposed method in various cases.
An efficient computational method is developed for large-displacement and small-strain analysis of 3D hi-modulus materials which are often found in civil, composite and biological engineering. Based on the parametric ...
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An efficient computational method is developed for large-displacement and small-strain analysis of 3D hi-modulus materials which are often found in civil, composite and biological engineering. Based on the parametric variational principle (PVP), a unified constitutive equation of 3D hi-modulus materials is proposed to deal with the problem of numerical instability. The small-strain hi-modulus problem is transformed into a standard linear complementarity problem that can be solved easily by the classic Lemke's algorithm. By using the co-rotational approach, the local PVP formulation is combined with an existing co-rotational formulation and a new tangent stiffness matrix, including a parametric variable, is derived for geometrically nonlinear analysis. Traditional stress iteration is not required for calculation of the nodal internal force when the Newton-Raphson scheme or Arc-length method is employed to solve the material and geometric nonlinear problem. Convergence of the proposed algorithm is improved greatly in contrast to the traditionally iterative solution. Also, the proposed algorithm is used to simulate a unilateral contact behavior of staggered bio-composites and the effective elasticity modulus of composites is determined accurately. (C) 2015 Elsevier B.V. All rights reserved.
Solution structures are typically average structures determined with the help of nmr‐derived distance and torsion angle information. However, when a biomolecule populates significantly different conformations, the av...
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Solution structures are typically average structures determined with the help of nmr‐derived distance and torsion angle information. However, when a biomolecule populates significantly different conformations, the average structure might be prone to artifacts, and other refinement strategies are necessary. For example, when experimental restraints are used in molecular dynamics simulations in a time‐averaged fashion (MDtar), the experimental structural information does no longer need to be satisfied at each step of the simulation; instead, the whole trajectory must agree with the restraints. However, the resulting structural ensembles are large and not unique and it is not trivial to extract the essential dynamic features for a system. Here we demonstrate that large MDtar ensembles can be simplified substantially by reducing the number of members to just a few on the basis of adjusting the individual probabilities of the members with the PDQPRO program [N. B. Ulyanov et al. Biophysical Journal (1995), Vol. 68, p. 13]. This algorithm finds the global minimum for a search function that represents the best match of a given ensemble with the experimental dipolar interproton relaxation rates. We have applied this strategy to a 17‐residue RNA hairpin, whose loop exhibited considerable flexibility evident from nmr data. This 17mer is a mimic of the TΨC‐loop of tRNA, where nucleotide 54 is usually a ribosylthymidine. The methylation of U54, which is completely buried in transfer ribonucleic acid, is administered by tRNA (m 5 U54)‐methyltransferase (RUMT). Since the 17mer is a good substrate for RUMT, we previously concluded that the flexibility of the 17mer's loop is a key to how RUMT gains access to the methylation site [L. J. Yao et al. Journal of Biomolecular NMR (1996) Vol. 9, p. 229]. Application of the PDQPRO algorithm to the previously acquired MDtar trajectories allowed us to reduce the number of conformations from several hundred to one major and five or six minor
Solution structures are typically average structures determined with the help of nmr-derived distance and torsion angle information. However;when a biomolecule populates significantly different conformations, the aver...
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Solution structures are typically average structures determined with the help of nmr-derived distance and torsion angle information. However;when a biomolecule populates significantly different conformations, the average structure might be prone to artifacts, and other refinement strategies are necessary. For example, when experimental restraints are used in molecular dynamics simulations in a time-averaged fashion (MDtar), the experimental structural information does no longer need to be satisfied at each step of the simulation;instead, the whole trajectory must agree with the restraints. However, the resulting structural ensembles are large and not unique and it is not trivial to extract the essential dynamic features for a system. Here we demonstrate that large MDtar ensembles can be simplified substantially by reducing the number of members to just a few on the basis of adjusting the individual probabilities of the members with the PDQPRO program [N. B. Ulyanov et al. Biophysical Journal (1995), Vol. 68, p. 13]. This algorithm finds the global minimum for a search function that represents the best match of a given ensemble with the experimental dipolar interproton relaxation rates. We have applied this strategy to a 17-residue RNA hairpin, whose loop exhibited considerable flexibility evident from nmr data. This 17mer is a mimic of the T Psi C loop of tRNA, where nucleotide 54 is usually a ribosylthymidine. The methylation of U54, which is completely buried in transfer ribonucleic acid, is administered by tRNA (m(5)U54)methyltransferase (RUMT). Since the 17mer is a good substrate for RUMT, we previously concluded that the flexibility of the 17mer's loop is a key to how RUMT gains access to the methylation site [L. J. Yao et al. Journal of Biomolecular NMR (1996) Vol. 9, p. 229]. Application of the PDQPRO algorithm to the previously acquired MDtar trajectories allowed us to reduce the number of conformations from several hundred to one major and five or six minor
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