Effect of the number of design variables in thickness optimization of concrete barrel roof shells using evolutionary algorithms

2019 ◽  
Vol 34 (3-4) ◽  
pp. 74-84
Author(s):  
Shadi Ostovari ◽  
Hooman Shayani
Keyword(s):  
Evolutionary Algorithms ◽  
Response Spectrum ◽  
Free Form ◽  
Thickness Optimization ◽  
Design Representation ◽  
Design Variables ◽  
Concrete Shells ◽  
Roof Shells ◽  
Practical Implications

This study looks into some practical implications of using evolutionary algorithms for optimization of free-form concrete shells in search of methods for automating design representation and determining the number of design variables. This study reports the insights and learnings from a set of numerical experiments, by changing the number of parameters, on thickness optimization of a barrel roof shell subjected to self-weight, an additional snow load, and an earthquake response spectrum. The practical advantages and challenges of two methods, parametric and direct representations, are analysed, and a spectrum of methods between these two extremes are investigated through experiments. The results demonstrate how changing the number of variables affects the quality of the design and the performance of the algorithm and why a systematic problem-dependent method for finding the best design representation and number of variables outside this spectrum can be beneficial.

Applying Expanded Servicescape to the Hotel Industry

2021 ◽  
pp. 109634802110115
Author(s):  
Seonjeong (Ally) Lee ◽  
Ning-Kuang Chuang
Keyword(s):  
Quality Of Life ◽  
Customer Loyalty ◽  
Physical Environment ◽  
Online Survey ◽  
Hotel Industry ◽  
Holistic Approach ◽  
Environmental Cues ◽  
Practical Implications

The physical environment plays an essential role in customers’ hotel stay experiences. Hotels offer a differentiated atmosphere that creates favorable customers’ evaluations. Based on the significant role of environmental cues, this study investigates the effects of an expanded servicescape on customers’ evaluations, including customer satisfaction, quality of life, and customer loyalty, in the context of the hotel industry. To test the proposed research framework, this study collects data from previous hotel customers and conducts a self-administered, online survey. Findings identified ambience, interactions with employees, authenticity, and fascination positively influenced customers’ satisfaction, which further influenced customer loyalty. Only ambience and fascination positively influenced quality of life, which in turn influenced customer loyalty. Results contributed to the application of expanded servicescape in the hotel context. Results also suggested practical implications of the holistic approach of servicescape in the hotel industry.

scholarly journals A Sequential Approach for Aerodynamic Shape Optimization with Topology Optimization of Airfoils

2021 ◽  
Vol 26 (2) ◽  
pp. 34
Author(s):  
Isaac Gibert Martínez ◽  
Frederico Afonso ◽  
Simão Rodrigues ◽  
Fernando Lau
Keyword(s):  
Topology Optimization ◽  
Shape Optimization ◽  
Volume Fraction ◽  
Optimization Techniques ◽  
Free Form ◽  
Aerodynamic Shape Optimization ◽  
Sequential Approach ◽  
Airfoil Surface ◽  
Aerodynamic Shape ◽  
Design Variables

The objective of this work is to study the coupling of two efficient optimization techniques, Aerodynamic Shape Optimization (ASO) and Topology Optimization (TO), in 2D airfoils. To achieve such goal two open-source codes, SU2 and Calculix, are employed for ASO and TO, respectively, using the Sequential Least SQuares Programming (SLSQP) and the Bi-directional Evolutionary Structural Optimization (BESO) algorithms; the latter is well-known for allowing the addition of material in the TO which constitutes, as far as our knowledge, a novelty for this kind of application. These codes are linked by means of a script capable of reading the geometry and pressure distribution obtained from the ASO and defining the boundary conditions to be applied in the TO. The Free-Form Deformation technique is chosen for the definition of the design variables to be used in the ASO, while the densities of the inner elements are defined as design variables of the TO. As a test case, a widely used benchmark transonic airfoil, the RAE2822, is chosen here with an internal geometric constraint to simulate the wing-box of a transonic wing. First, the two optimization procedures are tested separately to gain insight and then are run in a sequential way for two test cases with available experimental data: (i) Mach 0.729 at α=2.31°; and (ii) Mach 0.730 at α=2.79°. In the ASO problem, the lift is fixed and the drag is minimized; while in the TO problem, compliance minimization is set as the objective for a prescribed volume fraction. Improvements in both aerodynamic and structural performance are found, as expected: the ASO reduced the total pressure on the airfoil surface in order to minimize drag, which resulted in lower stress values experienced by the structure.

Would integrating women's professional care of pelvic organ prolapse improve the symptoms and quality of life: an integrative literature review

2020 ◽  
Vol 28 (2) ◽  
pp. 119-133
Author(s):  
Nicola Davies ◽  
Teresa Burdett
Keyword(s):  
Quality Of Life ◽  
Pelvic Organ Prolapse ◽  
Conservative Treatment ◽  
Conservative Management ◽  
Integrated Approach ◽  
Pelvic Organ ◽  
Social Implications ◽  
Content Type ◽  
Practical Implications

PurposeIntegrated healthcare is a central tenant of the NHS Long Term Plan (NHS, 2019). NICE in 2019 published guidelines; advising the integration of multidisciplinary professionals which may lead to an improvement in conservative treatment methods of pelvic organ prolapse. Therefore, current literature on the conservative treatments for pelvic organ prolapse needs to be reviewed to ascertain if an integrated approach would improve the symptoms and quality of life for women.Design/methodology/approachA systematic review of the literature between 2013 and 2018 was implemented. Papers included were written in English, peer-reviewed and consisted of treatments of pelvic organ prolapse in women. Papers containing surgical interventions, postpartum participants, reviews, evaluations, guidelines, follow-up studies, focusing on cost effectiveness, sexual function were excluded.FindingsSeven studies in total were included, and two overarching themes were identified: quality of life after treatment and the effect of conservative treatment on pelvic organ prolapse symptoms. The literature suggested that integrating care had a more positive outcome on pelvic organ symptoms and quality of life.Research limitations/implicationsTo develop a robust enhanced model of care for conservative treatment of pelvic organ prolapse through more mixed method or qualitative research, that incorporates integrative treatment methods with collaboration from multidisciplinary professionals.Practical implicationsThe practical implications of integrating the conservative management of pelvic organ prolapse is the communication between the multidisciplinary team must be exceptional to ensure everyone understands and agrees the treatment that is being provided to patient. Also, effective teamwork is important to ensure the patient receives the best care with input from the correct disciplines. The multi-professional team will need to have regular meetings to discuss and implement care plans for patients that might prove difficult to schedule due to differing commitments and priorities. This must be overcome to insure a successful and effective integrated approach to pelvic organ prolapse is delivered.Social implicationsThe social implications of integrating the professional approach to women's care of pelvic organ prolapse involves reducing the severity of the symptoms therefore, increasing the quality of life. This may result in the reduction of surgical intervention due to the patient being satisfied with the conservative management. Through integrating the management of the prolapse the patient will receive an accessible individualised care plan pathway that focuses on treating or reducing the impact of the symptoms that are bothersome to the patient whilst managing patient expectations. Patients will also, be reassured by the number of multi-disciplinary professionals involved in their care.Originality/valueGlobal integration of conservative treatments and multidisciplinary-professionals specialising in pelvic organ prolapse and pelvic floor dysfunction is needed.

Engine Mount Optimization for Vibration Isolation in Motorcycles

2006 ◽  
Author(s):  
Sudhir Kaul ◽  
Anoop K. Dhingra ◽  
Timothy G. Hunter
Keyword(s):  
Optimization Problem ◽  
Vibration Isolation ◽  
Total Force ◽  
Engine Mounts ◽  
The Road ◽  
Design Variables ◽  
Swing Arm ◽  
Engine Mount ◽  
Six Degree Of Freedom

This paper presents a comprehensive model to capture the dynamics of a motorcycle system in order to evaluate the quality of vibration isolation. The two main structural components in the motorcycle assembly - the frame and the swing-arm - are modeled using reduced order finite element models; the power-train assembly is modeled as a six degree-of-freedom (DOF) rigid body connected to the frame through the engine mounts and to the swing-arm through a shaft assembly. The engine mounts are modeled as tri-axial spring-damper systems. Models of the front-end assembly as well as front and rear tires are also included in the overall model. The complete vehicle model is used to solve the engine mount optimization problem so as to minimize the total force transmitted to the frame while meeting packaging and other side constraints. The mount system parameters - stiffness, position and orientation vectors - are used as design variables for the optimization problem. The imposed loads include forces and moments due to engine imbalance as well as loads transmitted due to irregularities in the road surface through the tire patch.

scholarly journals A sociology for other animals: analysis, advocacy, intervention

2016 ◽  
Vol 36 (3/4) ◽  
pp. 242-257 ◽  
Author(s):  
Erika Cudworth
Keyword(s):  
Animal Studies ◽  
Actor Network Theory ◽  
Political Agenda ◽  
Political Strategy ◽  
Advocacy Groups ◽  
Content Type ◽  
Secondary Sources ◽  
Central Argument ◽  
Practical Implications

Purpose – The purpose of this paper is to map the field of sociological animal studies through some examples of critical and mainstream approaches and considers their relation to advocacy. It makes the argument that while all these initiatives have made important contributions to the project of “animalising sociology” and suggest a need for change in species relations, the link between analysis and political strategy is uncertain. Design/methodology/approach – The paper develops its argument by using secondary sources, reviewing sociological positions and offering illustrations of possible interventions. Findings – Sociological interventions in the field of animal studies have been informed by critical perspectives, such as feminism and Marxism, or taken less critical routes deploying actor-network theory and symbolic interactionism. Whilst those working in critical traditions may appear to have a more certain political agenda, an analysis of “how things are” does not always lead to a clear position on “what is to be done” in terms of social movement agendas or policy intervention. In addition, concepts deployed in advocacy such as “liberation”, “quality of life” or “care” are problematic when applied beyond the human. Despite this, there are possibilities for coalition and solidarity around certain claims for change. Research limitations/implications – If the central argument of the paper were taken seriously by general sociologists, then sociology may be more open to “animal studies”. In implications for exisitng sociological animal studies scholarship is to trouble some of the certainties around advocacy. Practical implications – If the central argument of the paper were taken seriously by advocacy groups, then the hiatus between “welfarism” and “liberation” might be overcome. Originality/value – There have been recent attempts to map the field of scholarship in animal studies, but surprisingly little consideration of how different emergent positions inform questions of advocacy and the possibilities for political intervention.

Analysis of Solution Quality of Multiobjective Evolutionary Algorithms for Service Restoration in Distribution Systems

2017 ◽  
Vol 28 (6) ◽  
pp. 796-805
Author(s):  
Danilo Sipoli Sanches ◽  
Marcelo Favoretto Castoldi ◽  
João Bosco Augusto London ◽  
Alexandre Cláudio Botazzo Delbem
Keyword(s):  
Evolutionary Algorithms ◽  
Distribution Systems ◽  
Multiobjective Evolutionary Algorithms ◽  
Solution Quality ◽  
Service Restoration

Shareholder risk-taking incentives in the presence of contingent capital

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mahmoud Fatouh ◽  
Ayowande A. McCunn
Keyword(s):  
Risk Taking ◽  
Banking System ◽  
Capital Requirements ◽  
Content Type ◽  
Basic Model ◽  
Conversion Rates ◽  
A Minor ◽  
The Impact ◽  
Practical Implications

Purpose This paper aims to present a model of shareholders’ willingness to exert effort to reduce the likelihood of bank distress and the implications of the presence of contingent convertible (CoCo) bonds in the liabilities structure of a bank. Design/methodology/approach This study presents a basic model about the moral hazard surrounding shareholders willingness to exert effort that increases the likelihood of a bank’s success. This study uses a one-shot game and so do not capture the effects of repeated interactions. Findings Consistent with the existing literature, this study shows that the direction of the wealth transfer at the conversion of CoCo bonds determines their impact on shareholder risk-taking incentives. This study also finds that “anytime” CoCos (CoCo bonds trigger-able anytime at the discretion of managers) have a minor advantage over regular CoCo bonds, and that quality of capital requirements can reduce the risk-taking incentives of shareholders. Practical implications This study argues that shareholders can also use manager-specific CoCo bonds to reduce the riskiness of the bank activities. The issuance of such bonds can increase the resilience of individual banks and the whole banking system. Regulators can use restrictions on conversion rates and/or requirements on the quality of capital to address the impact of CoCo bonds issuance on risk-taking incentives. Originality/value To model the risk-taking incentives, authors generally modify the asset processes to introduce components that reflect asymmetric information between CoCo holders and shareholders and/or managers. This paper follows a simpler method similar to that of Holmström and Tirole (1998).

Constrained Shape Scaling of Trimmed NURBS Surfaces

1999 ◽  
Author(s):  
Pifu Zhang ◽  
Caiming Zhang ◽  
Fuhua (Frank) Cheng
Keyword(s):  
Data Exchange ◽  
Surface Deformation ◽  
Current Data ◽  
Free Form ◽  
Test Results ◽  
Nurbs Surface ◽  
Curvature Distribution ◽  
The Given ◽  
Boundary Curves

Abstract A method to scale and deform a trimmed NURBS surface while holding the shape and size of specific features (trimming curves) unchanged is presented. The new surface is formed by scaling the given surface according to the scaling requirement first; and then attaching the (original) features to the scaled NURBS surface at appropriate locations. The attaching process requires several geometric operations and constrained free-form surface deformation. The resulting surface has the same features as the original surface and same boundary curves as the scaled surface while reflecting the shape and curvature distribution of the scaled surface. This is achieved by minimizing a shape-preserving objective function which covers all the factors in the deformation process such as bending, stretching and spring effects. The resulting surface maintains a NURBS representation and, hence, is compatible with most of the current data-exchange standards. Test results on several car parts with trimming curves are included. The, quality of the resulting surfaces is examined using the highlight line model.

Finding Better Local Optima in Topology Optimization via Tunneling

2018 ◽  
Author(s):  
Shanglong Zhang ◽  
Julián A. Norato
Keyword(s):  
Topology Optimization ◽  
Optimization Problems ◽  
Structural Response ◽  
Free Form ◽  
Local Optima ◽  
Design Representation ◽  
Tunneling Method ◽  
Optimization Parameters ◽  
Gradient Based ◽  
Geometric Primitives

Topology optimization problems are typically non-convex, and as such, multiple local minima exist. Depending on the initial design, the type of optimization algorithm and the optimization parameters, gradient-based optimizers converge to one of those minima. Unfortunately, these minima can be highly suboptimal, particularly when the structural response is very non-linear or when multiple constraints are present. This issue is more pronounced in the topology optimization of geometric primitives, because the design representation is more compact and restricted than in free-form topology optimization. In this paper, we investigate the use of tunneling in topology optimization to move from a poor local minimum to a better one. The tunneling method used in this work is a gradient-based deterministic method that finds a better minimum than the previous one in a sequential manner. We demonstrate this approach via numerical examples and show that the coupling of the tunneling method with topology optimization leads to better designs.

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