Estimation of Solar Irradiance on Solar Fields: An Analytical Approach and Experimental Results

An approximate model for the elastic-plastic analysis of a pipe element under combined loading is developed. The model is obtained by generalizing a limit load solution for combined pressure, bending, torsion and axial load to include strain hardening. For various combinations of loading of tubes, curvatures and twist angles are predicted and compared with experimental results and those predicted by a more rigorous analytical approach. The comparison shows that good results are obtained from the approximate model.

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Kapees3: A High-Quality VLSI Placement Tool Using Nesterov’s Method for Density Penalty

Journal of Circuits System and Computers ◽

10.1142/s0218126618501220 ◽

2018 ◽

Vol 27 (08) ◽

pp. 1850122

Author(s):

Sameer Pawanekar ◽

Kalpesh Kapoor ◽

Gaurav Trivedi

Keyword(s):

Nonlinear Programming ◽

Nonlinear Equations ◽

Analytical Approach ◽

Quadratic Optimization ◽

Experimental Results ◽

Standard Cell ◽

Feng Shui ◽

High Quality ◽

Cell Placement ◽

Number Of Cells

We present an analytical approach that is based on nonlinear programming to perform VLSI standard cell placement. Our method first clusters a netlist to reduce the number of cells and then performs quadratic optimization on the reduced netlist. Finally, it uses Nesterov’s method for solving nonlinear equations for the problem. The framework of our tool, Kapees3, is scalable and generates high quality results. The experimental results for Peko Suite 1 and Peko Suite 2 benchmarks show promising improvements. Our placement tool outperforms NTUPlace3, Dragon, Feng Shui, Capo10.5, by 46%, 57%, 48% and 25%, respectively, on PEKO Suite 1. For PEKO Suite 2, our placement tool outperforms NTUPlace3, Dragon, Feng Shui, Capo10.5 and mPL6 by 30%, 47%, 57%, 69% and 2.7%, respectively. On MMS benchmarks, we obtain wirelength improvement over Capo10.5 by 56.62%, FLOP by 7.84%, FastPlace by 11.55%, ComPLx by 4.58%, POLAR by 23.67%, mPL6 by 9.96% and NTUPlace3-Unified by 2.96%.

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Assessment of the early-age strains and stresses in 2D restrained self-stressed members

Budownictwo i Architektura ◽

10.35784/bud-arch.2131 ◽

2020 ◽

Vol 19 (4) ◽

pp. 085-094

Author(s):

Viktar V. Tur ◽

Volha H. Sannikava

Keyword(s):

Analytical Approach ◽

Experimental Results ◽

Development Model ◽

Early Age ◽

Steel Tubes ◽

Mesh Reinforcement ◽

Centre Of Gravity ◽

Expansive Concrete ◽

Iterative Procedures ◽

Concrete Filled Steel Tubes

The paper presents the implementation of the modified strains development model (MSDM) for the two-way restrained self-stressed members such as expansive concrete-filled steel tubes and expansive concrete plane elements with arbitrary orthogonal reinforcement. The analytical approach allows defining the restrained strains and stresses in any 2D restraint conditions by following the iterative procedures and accounting for the elastic-plastic behaviour of expansive concrete at an early age. The consistency of the proposed method was confirmed by assessing the experimental results of the two series of the expansive concrete-filled steel tubes and three series of the expansive concrete plane members with mesh reinforcement in the centre of gravity.

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Analysing data with repeated observations on each experimental unit

The Journal of Agricultural Science ◽

10.1017/s0021859600027763 ◽

1976 ◽

Vol 87 (2) ◽

pp. 423-432 ◽

Cited By ~ 227

Author(s):

J. G. Rowell ◽

D. E. Walters

Keyword(s):

Analytical Approach ◽

Experimental Results ◽

Experimental Unit ◽

Repeated Observations ◽

Plot Analysis ◽

Split Plot ◽

Scant Attention ◽

Over Time

SummarySplit-plot (or split-block) analyses are commonly applied to experimental results where several successive observations of the same variable have been recorded on each experimental unit. The assumptions required for such analyses receive scant attention and it often seems unlikely that these assumptions would be satisfied in experimental situations. Five sets of results are presented to support this proposition. An alternative analytical approach is suggested in which contrasts over time are analysed; such a method is always valid, computationally simple, and readily interpretable, and may also be used to gauge the validity of the split-plot analysis.

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The stresses induced in reinforced plastic matrix pipes by saddle supports

The Journal of Strain Analysis for Engineering Design ◽

10.1243/03093247v173147 ◽

1982 ◽

Vol 17 (3) ◽

pp. 147-155 ◽

Cited By ~ 2

Author(s):

C B Greatorex ◽

A S Tooth

Keyword(s):

Analytical Approach ◽

Shell Theory ◽

Experimental Results ◽

Pipe Material ◽

Design Features ◽

Analytical Results ◽

Reinforced Plastic ◽

Pipe Radius ◽

Series Of Experiments ◽

Plastic Matrix

The results of a series of experiments conducted on reinforced plastic matrix pipes show how the peak stresses, occurring in the saddle support region, can be reduced in magnitude by certain design features. Two methods are found of value: (1) to use a flexible medium, such as PVC or rubber, between the saddle and pipe, and (2) to support the pipe on a saddle with a radius greater than the pipe radius. The experimental results are compared with an analytical approach using shell theory making the assumption that the pipe material is isotropic. The agreement between the experimental and analytical results is promising.

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An Analytical Approach for Deformation Shapes of a Cylindrical Shell with Internal Medium Subjected to Lateral Contact Explosive Loading

Mathematical Problems in Engineering ◽

10.1155/2015/563097 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Xiangyu Li ◽

Zhenduo Li ◽

Minzu Liang

Keyword(s):

Cylindrical Shell ◽

Explosive Charge ◽

Analytical Approach ◽

Plastic Hinge ◽

Experimental Results ◽

Rigid Plastic ◽

Lateral Contact ◽

Internal Medium ◽

Contact Explosion ◽

Spring Force

An experimental investigation on deformation shape of a cylindrical shell with internal medium subjected to lateral contact explosion was carried out briefly. Deformation shapes at different covered width of lateral explosive were recovered experimentally. Based on the experimental results, a corresponding analytical approach has been undertaken with rigid plastic hinge theory. In the analytical model, the cylindrical shell is divided into end-to-end rigid square bars. Deformation process of the cylindrical shell is described by using the translations and rotations of all rigid square bars. Expressions of the spring force, buckling moment, and deflection angle between adjacent rigid square bars are conducted theoretically. Given the structure parameters of the cylinder and the type of the lateral explosive charge, deformation processes and shapes are reported and discussed using the analytical approach. A good agreement has been obtained between calculated and experimental results, and thus the analytical approach can be considered as a valuable tool in understanding the deformation mechanism and predicting the deformation shapes of the cylindrical shell with internal medium subjected to lateral contact explosion. Finally, parametric studies are carried out to analyze the effects of deformation shape, including the covered width of the lateral explosive, explosive charge material, and distribution of initial velocity.

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A Simple Analytical Approach for Creep Analysis of EB-FRP Systems

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.774.42 ◽

2018 ◽

Vol 774 ◽

pp. 42-47 ◽

Cited By ~ 1

Author(s):

Hugo Biscaia ◽

Carlos Chastre

Keyword(s):

Analytical Approach ◽

Bond Stress ◽

Experimental Results ◽

Elastic Regime ◽

Analytical Results ◽

Creep Analysis ◽

Proposed Model ◽

Initial Load

Based on a few experimental results available in the literature, this work presents a simple analytical approach that allows the study of the long-term behaviour of CFRP-to-concrete interfaces under an initial sustaining load. Only the elastic regime is studied, which means that the interfacial maximum bond stress and maximum slip are never exceeded. Therefore, the maximum initial load to be sustained by the joints is limited by its corresponding elastic value. The analytical results provided by the proposed model are compared with some experimental results found in the literature. The results showed strain redistribution throughout the bonded length over the time.

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Analytical investigation of well/perforation scale effect on sand production of weakly consolidated sandstones

The APPEA Journal ◽

10.1071/aj15029 ◽

2016 ◽

Vol 56 (1) ◽

pp. 405 ◽

Cited By ~ 1

Author(s):

Soroush Tehrani ◽

Mohammad Sarmadivaleh ◽

Ahmadreza Younessi Sinaki ◽

Masood Mostofi ◽

Massoud Bayati

Keyword(s):

Scale Effect ◽

Analytical Approach ◽

Failure Criteria ◽

Analytical Investigation ◽

Experimental Results ◽

Outer Diameter ◽

Sand Production ◽

Effect Factor ◽

Open Hole ◽

Walled Cylinder

Investigating the risk of sand production is a common practice for developing unconsolidated and weakly consolidated reservoirs, particularly with designing the completion system of development wells. The risk of sanding may be different for open hole and cased and perforated completion systems. Part of this difference is a result of the different size of the boreholes—that is, open hole versus perforation tunnels— which is known as borehole scale effect. The amount of research dedicated to investigate the borehole scale effect on sand production is very limited. Research has been carried out by conducting thick-walled cylinder (TWC) tests on samples with different inner to outer diameter ratios. The impacts of sample size and boundaries on the induced stresses around the borehole and failure were, however, not differentiated from the borehole scale effect. In this paper, a comprehensive analytical approach is performed to investigate the effect of the size of the sample and boundaries on TWC tests and borehole failure. To do this, four different failure criteria—Mohr-Coulomb, Drucker-Prager, Mogi and modified Lade—are compared with previously published experimental results. The analysis shows that the size of the sample and the boundaries may significantly change the TWC strength of the rock. The TWC changes by different inner to outer diameter ratios, however, may not be fully justified by the analytical approach. Hence, a scale effect factor must be introduced to replicate the experimental results.

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