A Self-Contained Architecture for Energy Recovery in Hydraulic Elevators

2014 ◽  
Author(s):  
Oscar Pena ◽  
Michael J. Leamy
Keyword(s):  
Analytical Model ◽  
Electric Motor ◽  
High Fidelity ◽  
The Novel ◽  
Heavy Equipment ◽  
Hydraulic Machines ◽  
Wide Range ◽  
Single Input ◽  
Main Components ◽  
Operation Cycle

This paper presents a novel energy storage and recovery architecture for speed-controlled hydraulic actuation in hydraulic elevators. The study is motivated by a need to increase efficiency in the fluid power industry, in general, and hydraulic elevators, in particular. In contrast to previously employed systems, the proposed architecture eliminates the need for throttling and inefficient energy conversions in electric motor/generators. The system has 6 main components: 1 actuator, 1 hydraulic transformer composed of 2 pump/motors, 2 accumulators, a reservoir or small auxiliary accumulator, and a small auxiliary electric motor to recharge accumulators. By operating in 3 different modes, the system is always able to recapture energy when decreasing actuation speed, and return energy if needed when increasing actuation speed. Assessment of the proposed architecture is accomplished through high-fidelity simulations and a simplified analytical model. The analytical model is derived with the pump/motor displacements as a single input. A heuristic rule-based control is developed to control the high-fidelity simulation through an operation cycle and a comparison to a counterweighted elevator simulation is done to validate energy advantages of the novel system. Preliminary results demonstrate the ability of the system to follow a velocity profile using a single input. Comparison with a conventional counterweighted hydraulic elevator shows a large increase in energy efficiency. It is believed the architecture may have additional applicability to a wide range of hydraulic machines, such as heavy equipment used in construction, manufacturing, forestry, etc.

Reading Beyond the Code

2018 ◽  
Keyword(s):  
Relevance Theory ◽  
Literary Studies ◽  
The Novel ◽  
Human Communication ◽  
Communicative Acts ◽  
Face To Face ◽  
Code Model ◽  
Wide Range ◽  
Central Claim

This book explores the value for literary studies of relevance theory, an inferential approach to communication in which the expression and recognition of intentions plays a major role. Drawing on a wide range of examples from lyric poetry and the novel, nine of the ten chapters are written by literary specialists and use relevance theory both as an overall framework and as a resource for detailed analysis. The final chapter, written by the co-founder of relevance theory, reviews the issues addressed by the volume and explores their implications for cognitive theories of how communicative acts are interpreted in context. Originally designed to explain how people understand each other in everyday face-to-face exchanges, relevance theory—described in an early review by a literary scholar as ‘the makings of a radically new theory of communication, the first since Aristotle’s’—sheds light on the whole spectrum of human modes of communication, including literature in the broadest sense. Reading Beyond the Code is unique in using relevance theory as a prime resource for literary study, and is also the first to apply the model to a range of phenomena widely seen as supporting an ‘embodied’ conception of cognition and language where sensorimotor processes play a key role. This broadened perspective serves to enhance the value for literary studies of the central claim of relevance theory: that the ‘code model’ is fundamentally inadequate to account for human communication, and in particular for the modes of communication that are proper to literature.

scholarly journals Novel Protein-Repellent and Antibacterial Resins and Cements to Inhibit Lesions and Protect Teeth

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Li Cao ◽  
Junling Wu ◽  
Qiang Zhang ◽  
Bashayer Baras ◽  
Ghalia Bhadila ◽  
...  
Keyword(s):  
Orthodontic Treatment ◽  
The Novel ◽  
Dental Resin ◽  
Biofilm Growth ◽  
New Class ◽  
Dental Resins ◽  
Wide Range ◽  
Oral Biofilms ◽  
One Year

Orthodontic treatment is increasingly popular as people worldwide seek esthetics and better quality of life. In orthodontic treatment, complex appliances and retainers are placed in the patients’ mouths for at least one year, which often lead to biofilm plaque accumulation. This in turn increases the caries-inducing bacteria, decreases the pH of the retained plaque on an enamel surface, and causes white spot lesions (WSLs) in enamel. This article reviews the cutting-edge research on a new class of bioactive and therapeutic dental resins, cements, and adhesives that can inhibit biofilms and protect tooth structures. The novel approaches include the use of protein-repellent and anticaries polymeric dental cements containing 2-methacryloyloxyethyl phosphorylcholine (MPC) and dimethylaminododecyl methacrylate (DMAHDM); multifunctional resins that can inhibit enamel demineralization; protein-repellent and self-etching adhesives to greatly reduce oral biofilm growth; and novel polymethyl methacrylate resins to suppress oral biofilms and acid production. These new materials could reduce biofilm attachment, raise local biofilm pH, and facilitate the remineralization to protect the teeth. This novel class of dental resin with dual benefits of antibacterial and protein-repellent capabilities has the potential for a wide range of dental and biomedical applications to inhibit bacterial infection and protect the tissues.

scholarly journals Multi-stable composite twisting structure for morphing applications

2012 ◽  
Vol 468 (2141) ◽  
pp. 1230-1251 ◽  
Author(s):  
X. Lachenal ◽  
P. M. Weaver ◽  
S. Daynes
Keyword(s):  
Analytical Model ◽  
Material Properties ◽  
Degrees Of Freedom ◽  
Design Parameters ◽  
Engineering Structures ◽  
The Past ◽  
Wide Range ◽  
Morphing Structure ◽  
Low Mass ◽  
Unstable States

Conventional shape-changing engineering structures use discrete parts articulated around a number of linkages. Each part carries the loads, and the articulations provide the degrees of freedom of the system, leading to heavy and complex mechanisms. Consequently, there has been increased interest in morphing structures over the past decade owing to their potential to combine the conflicting requirements of strength, flexibility and low mass. This article presents a novel type of morphing structure capable of large deformations, simply consisting of two pre-stressed flanges joined to introduce two stable configurations. The bistability is analysed through a simple analytical model, predicting the positions of the stable and unstable states for different design parameters and material properties. Good correlation is found between experimental results, finite-element modelling and predictions from the analytical model for one particular example. A wide range of design parameters and material properties is also analytically investigated, yielding a remarkable structure with zero stiffness along the twisting axis.

Development of a Methodology for Model Testing of Utor Welded Joints of a Vertical Cylindrical Tank

2021 ◽  
pp. 21-27
Author(s):  
D.A. Neganov ◽  
◽  
A.E. Zorin ◽  
O.I. Kolesnikov ◽  
G.V. Nesterov ◽  
...  
Keyword(s):  
Welded Joints ◽  
Strain State ◽  
Welded Joint ◽  
Design Parameters ◽  
Cylindrical Tank ◽  
Stress Strain ◽  
The Real ◽  
Stress Strain State ◽  
Hydraulic Machines ◽  
Wide Range

The methodology of laboratory modeling of the loading of utor welded joint of the tank is presented. The methodology is based on testing of the special design sample. It allows under uniaxial tension on the typical servo-hydraulic machines to reproduce in the zone of a utor welded joint the combined action of bending and shear forces, similar to that which occurs during the operation of a vertical cylindrical tank. To assess the distribution of the stress-strain state in the proposed design of the sample under its loading, the finite element modeling was performed in the ANSYS software package. It showed the fundamental correspondence of the stress distribution in the zone of the utor node in the sample and in the real tank. The experimental studies consisted in carrying out tests for the durability of a series of 16 samples loaded with the maximum force in the cycle, causing the calculated stresses in the zone of the welded utor node in the range of 100–200 % from the maximum permissible ones. The obtained results showed that the maximum loaded zone, where the destruction of the samples occurred, is the near-seam zone of the utor welded joint on the inside of the tank. This corresponds to the statistics of the real tank failures. It is established that the developed methodology ensures the possibility of carrying out correct resource tests of the tank utor welded joints. It is also possible to vary the stress-strain state scheme within a wide range in the area of the utor welded joint by changing the design parameters of the test sample. In compliance with the regulated welding technologies and the absence of unacceptable defects in the welded joint, the utor node has a high resource, which significantly exceeding 50 years of the tank operation.

Creativity from perspective of axiology

2021 ◽  
Vol 92 (2) ◽  
pp. 10-20
Author(s):  
A. V Kiriakova ◽  
◽  
V.V. Moroz ◽  
Keyword(s):  
Evolutionary Process ◽  
Value Orientations ◽  
Point Of View ◽  
Modern World ◽  
Collective Creativity ◽  
The Social ◽  
Wide Range ◽  
Interdisciplinary Knowledge ◽  
Main Components ◽  
The Individual

Interest in creativity as a subject of research has been growing exponentially since the second half of the 20th century in all areas of human history. A wide range of both domestic and foreign studies allows authors to assert that creativity is a personality trait, inherent to one degree or another. Whereas the development of such trait becomes an urgent necessity in the new reality. The entire evolutionary process of the social development illustrates its dependence on personal and collective creativity. The aim of this research is to study the phenomenon of creativity through the perspective of axiology, i.e. the science of values. Axiology allows us to consider the realities of the modern world from the perspective of not only external factors, circumstances and situations, but also of deep value foundations. Creativity has been studied quite deeply from the point of view of psychology: the special characteristics of a creative person, stages of the creative process, the relationship between creative and critical thinking, creativity and intelligence. Some psychologists emphasize motivation, creative skills, interdisciplinary knowledge, and the creative environment as the main components that contribute to the development of creativity. The authors of the article argue that values and value orientations towards cognition, creativity, self-realization and self-expression are the drivers of creativity. In a broad sense, values as a matrix of culture determine the attitude of society to creativity, to the development of creativity of the individual and the creative class, and to how economically successful a given society will be. Since innovation and entrepreneurship are embodied creativity. Thus, the study of creativity from the perspective of axiology combines the need for a deep study of this phenomenon and the subjective significance of creativity in the context of new realities

Stranger Fictions

2021 ◽  
Author(s):  
Rebecca C. Johnson
Keyword(s):  
World Literature ◽  
Arab World ◽  
Central Place ◽  
Arabic Literature ◽  
The Novel ◽  
Reading Practices ◽  
Global Circulation ◽  
Wide Range ◽  
History Of ◽  
Modern Arabic

Zaynab, first published in 1913, is widely cited as the first Arabic novel, yet the previous eight decades saw hundreds of novels translated into Arabic from English and French. This vast literary corpus influenced generations of Arab writers but has, until now, been considered a curious footnote in the genre's history. Incorporating these works into the history of the Arabic novel, this book offers a transformative new account of modern Arabic literature, world literature, and the novel. This book rewrites the history of the global circulation of the novel by moving Arabic literature from the margins of comparative literature to its center. Considering the wide range of nineteenth- and early-twentieth-century translation practices, the book argues that Arabic translators did far more than copy European works; they authored new versions of them, producing sophisticated theorizations of the genre. These translations and the reading practices they precipitated form the conceptual and practical foundations of Arab literary modernity, necessitating an overhaul of our notions of translation, cultural exchange, and the global. The book shows how translators theorized the Arab world not as Europe's periphery but as an alternative center in a globalized network. It affirms the central place of (mis)translation in both the history of the novel in Arabic and the novel as a transnational form itself.

scholarly journals Synthesis of photoreactive solvent-free acrylic pressure-sensitive adhesives in the recovered system

2007 ◽  
Vol 9 (2) ◽  
pp. 5-9 ◽  
Author(s):  
Roland Milker ◽  
Zbigniew Czech ◽  
Marta Wesołowska
Keyword(s):  
Organic Solvent ◽  
Solvent Free ◽  
The Novel ◽  
Pressure Sensitive Adhesive ◽  
Adhesive Film ◽  
Pressure Sensitive Adhesives ◽  
Pressure Sensitive ◽  
Wide Range ◽  
Protective Films ◽  
New Type

Synthesis of photoreactive solvent-free acrylic pressure-sensitive adhesives in the recovered system The present paper discloses a novel photoreactive solvent-free acrylic pressure-sensitive adhesive (PSA) systems, especially suitable for the so much adhesive film applications as the double-sided, single-sided or carrier-free technical tapes, self-adhesive labels, protective films, marking and sign films and wide range of medical products. The novel photoreactive solvent-free pressure-sensitive adhesives contain no volatile organic compounds (residue monomers or organic solvent) and comply with the environment and legislation. The synthesis of this new type of acrylic PSA is conducted in common practice by solvent polymerisation. After the organic solvent are removed, there remains a non-volatile, solvent-free highly viscous material, which can be processed on a hot-melt coating machine at the temperatures of about 100 to 140°C.

Method for Non-Dimensional Tip Leakage Flow Characterization in Radial Turbines

2018 ◽  
Author(s):  
José Ramón Serrano ◽  
Roberto Navarro ◽  
Luis Miguel García-Cuevas ◽  
Lukas Benjamin Inhestern
Keyword(s):  
Suction Side ◽  
Tip Clearance ◽  
Navier Stokes ◽  
The Novel ◽  
Tip Leakage Flow ◽  
Navier Stokes Equation ◽  
Tip Clearance Flow ◽  
Tip Leakage ◽  
Wide Range ◽  
Clearance Flow

Tip leakage loss characterization and modeling plays an important role in small size radial turbine research. The momentum of the flow passing through the tip gap is highly related with the tip leakage losses. The ratio of fluid momentum driven by the pressure gradient between suction side and pressure side and the fluid momentum caused by the shroud friction has been widely used to analyze and to compare different sized tip clearances. However, the commonly used number for building this momentum ratio lacks some variables, as the blade tip geometry data and the viscosity of the used fluid. To allow the comparison between different sized turbocharger turbine tip gaps, work has been put into finding a consistent characterization of radial tip clearance flow. Therefore, a non-dimensional number has been derived from the Navier Stokes Equation. This number can be calculated like the original ratio over the chord length. Using the results of wide range CFD data, the novel tip leakage number has been compared with the traditional and widely used ratio. Furthermore, the novel tip leakage number can be separated into three different non-dimensional factors. First, a factor dependent on the radial dimensions of the tip gap has been found. Second, a factor defined by the viscosity, the blade loading, and the tip width has been identified. Finally, a factor that defines the coupling between both flow phenomena. These factors can further be used to filter the tip gap flow, obtained by CFD, with the influence of friction driven and pressure driven momentum flow.

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