Multi-objective search-based software modularization: structural and non-structural features

2018 ◽  
Vol 23 (21) ◽  
pp. 11141-11165 ◽  
Author(s):  
Nafiseh Sadat Jalali ◽  
Habib Izadkhah ◽  
Shahriar Lotfi
Keyword(s):  
Structural Features ◽  
Multi Objective ◽  
Software Modularization

scholarly journals An Improved Multi-Objective Evolutionary Approach for Aerospace Shell Production Scheduling Problem

Symmetry ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 509
Author(s):  
Qing Wang ◽  
Xiaoshuang Wang ◽  
Haiwei Luo ◽  
Jian Xiong
Keyword(s):  
Evolutionary Algorithm ◽  
Production Scheduling ◽  
Production Line ◽  
Optimization Problems ◽  
Structural Features ◽  
Optimization Process ◽  
Scheduling Problems ◽  
Multi Objective Optimization ◽  
Multi Objective ◽  
Shell Production

To certain degree, multi-objective optimization problems obey the law of symmetry, for instance, the minimum of one objective function corresponds to the maximum of another objective. To provide effective support for the multi-objective operation of the aerospace product shell production line, this paper studies multi-objective aerospace shell production scheduling problems. Firstly, a multi-objective optimization model for the production scheduling of aerospace product shell production lines is established. In the presented model, the maximum completion time and the cost of production line construction are optimized simultaneously. Secondly, to tackle the characteristics of discreteness, non-convexity and strong NP difficulty of the multi-objective problem, a knowledge-driven multi-objective evolutionary algorithm is designed to solve the problem. In the proposed approach, structural features of the scheduling plan are extracted during the optimization process and used to guide the subsequent optimization process. Finally, a set of test instances is generated to illustrate the addressed problem and test the proposed approach. The experimental results show that the knowledge-driven multi-objective evolutionary algorithm designed in this paper has better performance than the two classic multi-objective optimization methods.

Multi-Objective Modeling of Herbicidal Activity from an Environmentally Friendly Perspective

2017 ◽  
Vol 2 (2) ◽  
pp. 16-26 ◽  
Author(s):  
Joyce K Daré ◽  
Stephen J Barigye ◽  
Matheus P. Freitas
Keyword(s):  
Weed Management ◽  
Photosynthetic Electron Transport ◽  
Structural Features ◽  
Herbicidal Activity ◽  
Soil Sorption ◽  
Qspr Model ◽  
Multi Objective ◽  
Validation Parameters ◽  
Triazine Derivatives ◽  
Qspr Modeling

Despite the attractiveness in weed management, herbicides can produce several hazardous effects due to their persistence in the environment. It is therefore important to strike a balance between the herbicidal activity and ecotoxicological profile. The aim of the present paper is to perform a multi-objective QSPR modeling of the bioactivity and soil sorption profile of a dataset of triazine derivatives, in order to gain understanding on the structural features favoring both high herbicidal activity and low soil sorption. To this end, the Photosynthetic Electron Transport (PET) inhibitory activity and the logKOC are selected, and a MIA-QSPR model is built for the pI50/log Koc ratio. The obtained model presented satisfactory performance evidenced by the calibration and validation parameters. Structural interpretation of the built model is performed using the recently implemented MIA-Plot tool, providing important guidelines on the structural moieties related with high pI50/logKOC ratio values as a desirable requirement in the development of high activity and eco-friendly triazines.

scholarly journals Multi-Objective Analysis for the Optimization of a High Performance Slab-on- Ground Floor in a Warm Climate

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2988
Author(s):  
Cristina Baglivo ◽  
Paolo Congedo ◽  
Delia D’Agostino
Keyword(s):  
Energy Demand ◽  
High Surface ◽  
Building Design ◽  
Structural Features ◽  
Objective Analysis ◽  
Design Stage ◽  
Warm Climate ◽  
Surface Mass ◽  
Ground Floor ◽  
Multi Objective

The building sector is responsible for a large part of the overall energy demand in Europe. Energy consumption may be reduced at the design stage by selecting the proper building elements. This study develops a multi-objective analysis for a highly efficient slab-on-ground floor, whose design is optimized for a warm climate. Possible floor configurations have been obtained using the software tools modeFRONTIER, for the multi-objective analysis, and MATLAB, for the computational code. To proceed with the optimization of the different floor layers, a dataset has been developed for several materials in relation to a number of parameters: thermo-physical properties, eco-sustainability score according to the ITACA Protocol, costs, source, and structural features. Results highlight how a high surface mass is preferable when guaranteed by concrete in the innermost and outermost layers. Furthermore, insulating materials are better placed in the middle layers, with the insulating and synthetic materials adjacent to the ground and insulating and natural materials adjacent to the floor. Results emphasize the importance of thermal transmittance close to the Italian regulation limit (0.38 W/m2 K) in the climatic zone C, to allow an adequate exchange with the ground in summer, avoiding overheating. The outcomes show that the obtained slab-on-ground floor configurations favor the use of local, recyclable, sustainable, and eco-friendly materials, which is in line with energy policies and sustainability protocols. The paper supports the decision making process that takes many variables into account at the building design stage.

Multi-objective biomimetic optimization design of stiffeners for automotive door based on vein unit of dragonfly wing

2021 ◽  
pp. 095440622110534
Author(s):  
Fengxiang Xu ◽  
Junyao Wang ◽  
Lin Hua
Keyword(s):  
Finite Element ◽  
Optimization Design ◽  
Element Model ◽  
Structural Features ◽  
Operating Conditions ◽  
Topology Design ◽  
Topological Optimization ◽  
Biomimetic Design ◽  
Multi Objective ◽  
Dragonfly Wing

In this paper, a biomimetic optimizing design of the stiffeners layout of the automotive inner door panels is proposed based on vein unit of dragonfly wing. The distributions features of the dragonfly veins and similarity as stiffeners are analyzed, and then the excellent structural features of mechanical properties of the dragonfly veins are extracted to work as a biomimetic design. In order to research the distribution of the reinforced areas in the interior door panels under various operating conditions, the finite element model is established firstly. Secondly, gray relation theory combined with analytic hierarchy analysis are imposed to determine the weight value of each condition in multi-objective topology optimization to fully consider both objective and subjective factors, and topological optimization results indicate that the stiffeners of the inner door panel are biconically designed. Finally, the original finite element results of the inner door panels are compared with that after optimized with biomimetic stiffeners under the same operating conditions, and the result of the comparison verify the effectiveness of the biomimetic topology design. Specifically, for the dent-resistant and sinking condition, the strength of new door increases by 20.2% and 14.3%, respectively. Therefore, doors with biomimetic stiffeners have an increased resistance to deformation and vibration, while the mass is reduced by 2.7%. The results can provide valuable new ideas for the optimal biomimetic design of automotive door inner panel stiffeners.

Electron microscopy and diffraction studies of polyimides

1983 ◽  
Vol 41 ◽  
pp. 28-29
Author(s):  
O.C. de Hodgins ◽  
K. R. Lawless ◽  
R. Anderson
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Structural Features ◽  
Inert Atmosphere ◽  
Polyimide Films ◽  
Resolution Electron ◽  
The Matrix ◽  
High Resolution Electron Microscope ◽  
Diffraction Patterns ◽  
Polymeric Samples

Commercial polyimide films have shown to be homogeneous on a scale of 5 to 200 nm. The observation of Skybond (SKB) 705 and PI5878 was carried out by using a Philips 400, 120 KeV STEM. The objective was to elucidate the structural features of the polymeric samples. The specimens were spun and cured at stepped temperatures in an inert atmosphere and cooled slowly for eight hours. TEM micrographs showed heterogeneities (or nodular structures) generally on a scale of 100 nm for PI5878 and approximately 40 nm for SKB 705, present in large volume fractions of both specimens. See Figures 1 and 2. It is possible that the nodulus observed may be associated with surface effects and the structure of the polymers be regarded as random amorphous arrays. Diffraction patterns of the matrix and the nodular areas showed different amorphous ring patterns in both materials. The specimens were viewed in both bright and dark fields using a high resolution electron microscope which provided magnifications of 100,000X or more on the photographic plates if desired.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Measurement and Reduction of Radiation Damage in Frozen Hydrated Crystalline Specimens

1978 ◽  
Vol 36 (3) ◽  
pp. 70-77 ◽  
Author(s):  
R.M. Glaeser ◽  
S.B. Hayward
Keyword(s):  
Diffraction Pattern ◽  
Structural Information ◽  
Structural Disorder ◽  
Structural Features ◽  
Biological Macromolecules ◽  
Diffraction Intensity ◽  
Object Structure ◽  
Specimen Material ◽  
Unit Cells ◽  
Identical Unit

Highly ordered or crystalline biological macromolecules become severely damaged and structurally disordered after a brief electron exposure. Evidence that damage and structural disorder are occurring is clearly given by the fading and eventual disappearance of the specimen's electron diffraction pattern. The fading and disappearance of sharp diffraction spots implies a corresponding disappearance of periodic structural features in the specimen. By the same token, there is a oneto- one correspondence between the disappearance of the crystalline diffraction pattern and the disappearance of reproducible structural information that can be observed in the images of identical unit cells of the object structure. The electron exposures that result in a significant decrease in the diffraction intensity will depend somewhat upon the resolution (Bragg spacing) involved, and can vary considerably with the chemical makeup and composition of the specimen material.

Some Structural Features of Metaphase Chromosomes of Mice and Men

1967 ◽  
Vol 25 ◽  
pp. 190-191
Author(s):  
Godfrey C. Hoskins ◽  
Betty B. Hoskins
Keyword(s):  
Electron Microscopy ◽  
Electron Micrographs ◽  
Structural Features ◽  
Metaphase Chromosomes ◽  
The Future ◽  
Of Mice And Men ◽  
Mouse Cells ◽  
Human And Mouse

Metaphase chromosomes from human and mouse cells in vitro are isolated by micrurgy, fixed, and placed on grids for electron microscopy. Interpretations of electron micrographs by current methods indicate the following structural features.Chromosomal spindle fibrils about 200Å thick form fascicles about 600Å thick, wrapped by dense spiraling fibrils (DSF) less than 100Å thick as they near the kinomere. Such a fascicle joins the future daughter kinomere of each metaphase chromatid with those of adjacent non-homologous chromatids to either side. Thus, four fascicles (SF, 1-4) attach to each metaphase kinomere (K). It is thought that fascicles extend from the kinomere poleward, fray out to let chromosomal fibrils act as traction fibrils against polar fibrils, then regroup to join the adjacent kinomere.

Observations on the Structure of Ta2O5

1972 ◽  
Vol 30 ◽  
pp. 540-541
Author(s):  
P. S. Kotval ◽  
C. J. Dewit
Keyword(s):  
Electron Microscope ◽  
Structural Features ◽  
Amorphous Structure ◽  
Polished Surface ◽  
Distilled Water ◽  
Anodic Films ◽  
Amorphous Films ◽  
Beam Heating ◽  
Diffraction Patterns ◽  
Hexagonal Arrays

The structure of Ta2O5 has been described in the literature in several different crystallographic forms with varying unit cell lattice parameters. Earlier studies on films of Ta2O5 produced by anodization of tantalum have revealed structural features which are not consistent with the parameters of “bulk” Ta2O5 crystalsFilms of Ta2O5 were prepared by anodizing a well-polished surface of pure tantalum sheet. The anodic films were floated off in distilled water, collected on grids, dried and directly examined in the electron microscope. In all cases the films were found to exhibit diffraction patterns representative of an amorphous structure. Using beam heating in the electron microscope, recrystallization of the amorphous films can be accomplished as shown in Fig. 1. As suggested by earlier work, the recrystallized regions exhibit diffraction patterns which consist of hexagonal arrays of main spots together with subsidiary rows of super lattice spots which develop as recrystallization progresses (Figs. 2a and b).

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