scholarly journals On the Design of a Class of Rotary Compressors Using Bayesian Optimization

Machines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 219
Author(s):  
Kui Lu ◽  
Truong H. Phung ◽  
Ibrahim A. Sultan
Keyword(s):  
Black Box ◽  
Bayesian Optimization ◽  
Optimization Process ◽  
Design Parameters ◽  
Mathematical Form ◽  
The Novel ◽  
Numerical Illustration ◽  
Positive Displacement ◽  
Machine Performance ◽  
The Relationship

The optimization process of compressors is usually regarded as a ‘black-box’ problem, in which the mathematical form underlying the relationship between design parameters and the design objective is impractical and costly to be obtained. To solve the ‘black-box’ problem, Bayesian optimization has been proven as an accurate and efficient method. However, the application of such a method in the design of compressors is rarely discussed, particularly no work has been reported in terms of the positive displacement type compressor. Therefore, this paper aims to introduce the Bayesian optimization to the design of positive displacement compressors through the optimization process of the novel limaçon compressor. In this paper, a two-stage optimization process is presented, in which the first stage optimizes the geometric parameters as per design requirements and the second stage focuses on revealing an optimum setting of port geometries that improves machine performance. A numerical illustration is offered to prove the validity of the presented approach.

An Approach to Bayesian Optimization for Design Feasibility Check on Discontinuous Black-Box Functions

2020 ◽  
Author(s):  
Arpan Biswas ◽  
Christopher Hoyle
Keyword(s):  
Objective Function ◽  
Prior Knowledge ◽  
Design Space ◽  
Black Box ◽  
Training Data ◽  
Bayesian Optimization ◽  
Design Parameters ◽  
Classification Error ◽  
True Solution ◽  
Classification Tool

Abstract The paper presents a novel approach to apply Bayesian Optimization (BO) in predicting an unknown constraint boundary, also representing the discontinuity of an unknown function, for a feasibility check on the design space, thereby representing a classification tool to discern between a feasible and infeasible region. Bayesian optimization is an emerging field of study in the Sequential Design Methods where we learn and update our knowledge from prior evaluated designs, and proceed to the selection of new designs for future evaluation. It has been considered as a low-cost global optimization tool for design problems having expensive black-box objective functions. However, BO is mostly suited to problems with the assumption of a continuous objective function, and does not guarantee true convergence if the objective function has a discontinuity. This is because of the insufficient knowledge of the BO about the nature of the discontinuity of the unknown true function. Therefore, in this paper, we have proposed to predict the discontinuity of the objective function using a BO algorithm which can be considered as the pre-stage before optimizing the same unknown objective function. The proposed approach has been implemented in a thin tube design with the risk of creep-fatigue failure under constant loading of temperature and pressure. The stated risk depends on the location of the designs in terms of safe and unsafe regions, where the discontinuities lie at the transitions between those regions; therefore, the discontinuity has also been treated as an unknown constraint. The paper focuses on developing BO framework with maximizing the reformulated objective function on the same design space to predict the transition regions as a design methodology or classification tool between safe and unsafe designs, where we start with very limited data or no prior knowledge and then iteratively focus on sampling most designs near the transition region through better prior knowledge (training data) and thereby increase the accuracy of prediction to the true boundary while minimizing the number of expensive function evaluations. The converged model has been compared with the true solution for different design parameters and the results provided a classification error rate and function evaluations at an average of < 1% and ∼150, respectively. The results in this paper show some future research directions in extending the application of BO and considered as the proof of concept on large scale problem of complex diffusion bonded hybrid Compact Heat Exchangers.

scholarly journals Principal stress lines based design method of lightweight and low vibration amplitude gear web

2021 ◽  
Vol 18 (6) ◽  
pp. 7060-7075
Author(s):  
Ganjun Xu ◽  
◽  
Ning Dai ◽  
Sukun Tian ◽  
Keyword(s):  
Principal Stress ◽  
Vibration Amplitude ◽  
Design Method ◽  
Web Design ◽  
Design Parameters ◽  
The Novel ◽  
Experimental Platform ◽  
Gear Design ◽  
Optimal Distance ◽  
The Relationship

<abstract> <p>A lightweight and low vibration amplitude web design method was investigated to reduce gear weight and noise. It was based upon the relationship between length and orthogonality that the principal stress lines were designed at the gear web. By constructing a vibration control model with gear design parameters, the optimal distance was calculated. By offsetting the principal stress lines at the optimal distance, the lightweight gear web with the low vibration amplitude was then generated. A vibration experimental platform was built to verify the novel gear vibration performances, and it was compared with other gears with the same web's porosity to verify loading performance. The experimental results indicated that compared with the solid gear, the novel gear is 20.50% lighter and with a 29.46% vibration amplitude reduction.</p> </abstract>

An Approach to Bayesian Optimization for Design Feasibility Check on Discontinuous Black-Box Functions

2021 ◽  
Vol 143 (3) ◽  
Author(s):  
Arpan Biswas ◽  
Christopher Hoyle
Keyword(s):  
Fatigue Failure ◽  
Design Space ◽  
Black Box ◽  
Bayesian Optimization ◽  
Design Parameters ◽  
Classification Error ◽  
Support Vector ◽  
Thin Tube ◽  
Creep Fatigue ◽  
Training Cost

Abstract The paper presents a novel approach to applying Bayesian Optimization (BO) in predicting an unknown constraint boundary, also representing the discontinuity of an unknown function, for a feasibility check on the design space, thereby representing a classification tool to discern between a feasible and infeasible region. Bayesian optimization is a low-cost black-box global optimization tool in the Sequential Design Methods where one learns and updates knowledge from prior evaluated designs, and proceeds to the selection of new designs for future evaluation. However, BO is best suited to problems with the assumption of a continuous objective function and does not guarantee true convergence when having a discontinuous design space. This is because of the insufficient knowledge of the BO about the nature of the discontinuity of the unknown true function. In this paper, we have proposed to predict the location of the discontinuity using a BO algorithm on an artificially projected continuous design space from the original discontinuous design space. The proposed approach has been implemented in a thin tube design with the risk of creep-fatigue failure under constant loading of temperature and pressure. The stated risk depends on the location of the designs in terms of safe and unsafe regions, where the discontinuities lie at the transition between those regions; therefore, the discontinuity has also been treated as an unknown creep-fatigue failure constraint. The proposed BO algorithm has been trained to maximize sampling toward the unknown transition region, to act as a high accuracy classifier between safe and unsafe designs with minimal training cost. The converged solution has been validated for different design parameters with classification error rate and function evaluations at an average of &lt;1% and ∼150, respectively. Finally, the performance of our proposed approach in terms of training cost and classification accuracy of thin tube design is shown to be better than the existing machine learning (ML) algorithms such as Support Vector Machine (SVM), Random Forest (RF), and Boosting.

The role and relationship of mindreading and social attunement in HRI – position statements of interdisciplinary researchers. Workshop HRI'20

2020 ◽  
Author(s):  
Agnieszka Wykowska ◽  
Jairo Pérez-Osorio ◽  
Stefan Kopp
Keyword(s):  
Mental States ◽  
Human Robot Interaction ◽  
Human Interaction ◽  
Artificial Agents ◽  
The Novel ◽  
Robot Interaction ◽  
Novel Coronavirus ◽  
Relationship Of ◽  
The Relationship

This booklet is a collection of the position statements accepted for the HRI’20 conference workshop “Social Cognition for HRI: Exploring the relationship between mindreading and social attunement in human-robot interaction” (Wykowska, Perez-Osorio &amp; Kopp, 2020). Unfortunately, due to the rapid unfolding of the novel coronavirus at the beginning of the present year, the conference and consequently our workshop, were canceled. On the light of these events, we decided to put together the positions statements accepted for the workshop. The contributions collected in these pages highlight the role of attribution of mental states to artificial agents in human-robot interaction, and precisely the quality and presence of social attunement mechanisms that are known to make human interaction smooth, efficient, and robust. These papers also accentuate the importance of the multidisciplinary approach to advance the understanding of the factors and the consequences of social interactions with artificial agents.

Oleanolic Acid Derived from Plants: Synthesis and Pharmacological Properties of A-ring Modified Derivatives

2020 ◽  
Vol 17 (9) ◽  
pp. 1084-1101
Author(s):  
Tingjuan Wu ◽  
Xu Yao ◽  
Guan Wang ◽  
Xiaohe Liu ◽  
Hongfei Chen ◽  
...  
Keyword(s):  
Drug Design ◽  
Oleanolic Acid ◽  
Water Solubility ◽  
Future Application ◽  
The Novel ◽  
Pharmacological Effects ◽  
Framework Structure ◽  
Design And Synthesis ◽  
The Past ◽  
The Relationship

Background: Oleanolic Acid (OA) is a ubiquitous product of triterpenoid compounds. Due to its inexpensive availability, unique bioactivities, pharmacological effects and non-toxic properties, OA has attracted tremendous interest in the field of drug design and synthesis. Furthermore, many OA derivatives have been developed for ameliorating the poor water solubility and bioavailability. Objective: Over the past few decades, various modifications of the OA framework structure have led to the observation of enhancement in bioactivity. Herein, we focused on the synthesis and medicinal performance of OA derivatives modified on A-ring. Moreover, we clarified the relationship between structures and activities of OA derivatives with different functional groups in A-ring. The future application of OA in the field of drug design and development also was discussed and inferred. Conclusion: This review concluded the novel achievements that could add paramount information to the further study of OA-based drugs.

DIAGNOSING QUALITY OF FRICTION SYSTEMS OF MECHANISMS OF DEVICES

2019 ◽  
Vol 1 (7) ◽  
pp. 10-13
Author(s):  
D. Yu. Ershov ◽  
I. N. Lukyanenko ◽  
E. E. Aman
Keyword(s):  
Surface Defects ◽  
Diagnostic Methods ◽  
Design Parameters ◽  
Diagnostic Model ◽  
Mechanical Assemblies ◽  
Local Defects ◽  
Relationship Of ◽  
The Relationship ◽  
Production And Operation

The article shows the need to develop diagnostic methods for monitoring the quality of lubrication systems, which makes it possible to study the dynamic processes of contacting elements of the friction systems of instrument mechanisms, taking into account roughness parameters, the presence of local surface defects of elements and the bearing capacity of a lubricant. In the present article, a modern diagnostic model has been developed to control the quality of the processes of production and operation of friction systems of instrument assemblies. With the help of the developed model, it becomes possible to establish the relationship of diagnostic and design parameters of the mechanical system, as well as the appearance of possible local defects and lubricant state, which characterize the quality of friction systems used in many mechanical assemblies of the mechanisms of devices. The research results are shown in the form of nomograms to assess the defects of the elements of friction mechanisms of the mechanisms of the devices.

The Novel of Sensibility in the 1780s

2018 ◽  
Author(s):  
Caroline Franklin
Keyword(s):  
John Locke ◽  
Adam Smith ◽  
The Novel ◽  
Francis Hutcheson ◽  
Literary Movement ◽  
Epistolary Novels ◽  
The Relationship

This chapter studies the novels of sensibility in the 1780s. The philosophy of John Locke, Anthony Ashley Cooper, third Earl of Shaftesbury, Adam Smith, and Francis Hutcheson had influenced the first wave of epistolary novels of sensibility beginning in the 1740s. These explored the interaction between emotion and reason in producing moral actions. Response to stimuli was minutely examined, especially the relationship between the psychological and physiological manifestations of feelings. Later in the century, and, in particular during the late 1780s when the novel enjoyed a surge in popularity, the capacity for fine feeling became increasingly valued for its own sake rather than moralized. Ultimately, sensibility should be seen as a long-lasting literary movement rather than an ephemeral fashion. It put paternal authority and conventional modes of masculinity under question.

Mary Barton

2008 ◽  
Author(s):  
Elizabeth Gaskell
Keyword(s):  
Working Class ◽  
Elizabeth Gaskell ◽  
Class Conflict ◽  
The Novel ◽  
The Poor ◽  
Deep Sympathy ◽  
The Relationship ◽  
Class Community

‘It's the masters as has wrought this woe; it's the masters as should pay for it.’ Set in Manchester in the 1840s - a period of industrial unrest and extreme deprivation - Mary Barton depicts the effects of economic and physical hardship upon the city's working-class community. Paralleling the novel's treatment of the relationship between masters and men, the suffering of the poor, and the workmen's angry response, is the story of Mary herself: a factory-worker's daughter who attracts the attentions of the mill-owner's son, she becomes caught up in the violence of class conflict when a brutal murder forces her to confront her true feelings and allegiances. Mary Barton was praised by contemporary critics for its vivid realism, its convincing characters and its deep sympathy with the poor, and it still has the power to engage and move readers today. This edition reproduces the last edition of the novel supervised by Elizabeth Gaskell and includes her husband's two lectures on the Lancashire dialect.

Police Records

2019 ◽  
pp. 797-819
Author(s):  
Cristina Vatulescu
Keyword(s):  
Nineteenth Century ◽  
Detective Fiction ◽  
Media History ◽  
Late Nineteenth Century ◽  
The Novel ◽  
Police Records ◽  
History Of ◽  
Late Nineteenth ◽  
Relationship Of ◽  
The Relationship

This chapter approaches police records as a genre that gains from being considered in its relationships with other genres of writing. In particular, we will follow its long-standing relationship to detective fiction, the novel, and biography. Going further, the chapter emphasizes the intermedia character of police records not just in our time but also throughout their existence, indeed from their very origins. This approach opens to a more inclusive media history of police files. We will start with an analysis of the seminal late nineteenth-century French manuals prescribing the writing of a police file, the famous Bertillon-method manuals. We will then track their influence following their adoption nationally and internationally, with particular attention to the politics of their adoption in the colonies. We will also touch briefly on the relationship of early policing to other disciplines, such as anthropology and statistics, before moving to a closer look at its intersections with photography and literature.

Revisiting the Question of the Novel/Nation

2017 ◽  
Vol 46 (2) ◽  
pp. 76-82 ◽  
Author(s):  
Elliott Colla
Keyword(s):  
Arabic Literature ◽  
The Novel ◽  
Original Contribution ◽  
Palestinian Literature ◽  
The Relationship

In this essay, Arabic literature specialist and Arabic-English translator Elliott Colla explores the relationship between the novel and the nation, and reviews Bashir Abu-Manneh's ambitious and original contribution to the study of Palestinian literature.

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