A Unified Concept for the Graph Representation of Constraints in Mechanisms

2014 ◽  
Author(s):  
Andreas Müller ◽  
Offer Shai
Keyword(s):  
Rigid Bodies ◽  
The Body ◽  
Graph Representation ◽  
The Novel ◽  
Topological Graphs ◽  
Mixed Graph ◽  
Mixed Constraint ◽  
Constraint Graph ◽  
Special Cases ◽  
Machine Theory

There are two established approaches to represent constraints: the body-bar (BB) and the bar-joint (BJ) graph that can be used in machine theory. They are referred to as topological graphs as they describe the relation between members of a mechanism. It is known, however, that in many cases these graphs are not unique. Hence any method for kinematic analysis or mobility determination that is based on these topological graphs is prone to failures. In this paper a generalized and unified concept for the representation of constraints in mechanisms is introduced. It is first shown in which situations BB and BJ representations fail to correctly represent the mechanism. The novel constraint graph is then derived starting from the most general model of constrained rigid bodies. It is shown how BB and BJ graphs result as special cases. Therefore the new graph representation is called the ‘mixed graph’. It is further shown how this novel mixed constraint graph allows for computation of the correct generic (topological) mobility, and thus overcomes the problems of BB and BJ representations.

Applying Rigidity Theory Methods for Topological Decomposition and Synthesis of Gear Train Systems

2012 ◽  
Author(s):  
Maria Terushkin ◽  
Offer Shai
Keyword(s):  
Synthesis Method ◽  
Building Blocks ◽  
The Body ◽  
Computational Method ◽  
Gear Train ◽  
Graph Representation ◽  
Rigidity Theory ◽  
Graph Representations ◽  
Machine Theory ◽  
Gear Trains

This paper introduces a novel way to augment the knowledge and methods of rigidity theory to the topological decomposition and synthesis of gear train systems. A graph of gear trains, widely reported in the literature of machine theory, is treated as a graph representation from rigidity theory—the Body-Bar graph. Once we have this Body-Bar graph, methods and theorems from rigidity theory can be employed for analysis and synthesis. In this paper we employ the pebble-game algorithm, a computational method which allows determination of the topological mobility of mechanisms and the decomposition of gear trains into basic building blocks—Body-Bar Assur Graphs. Once we gain the ability to decompose any gear train into standalone components (Body-Bar Assur Graphs), this paper suggests inverting the process and applying the same method for synthesis. Relying on rigidity theory operations (Body-Bar extension, in this case), it is possible to construct all of the Body-Bar Assur Graphs, meaning the building blocks of gear trains. Once we have these building blocks at hand, it is possible to recombine them in various ways, providing us with a topological synthesis method for constructing gear trains. This paper also introduces a transformation between the Body-Bar graph and other graph representations used in mechanisms, thus leaving room for the application of the proposed synthesis and decomposition method directly to known graph representations already used in machine theory.

Atlas Database of 2-DOF Kinematic Chains and Its Application to the Creative Design of Mechanisms

2011 ◽  
Author(s):  
Huafeng Ding ◽  
Andre´s Kecskeme´thy ◽  
Zhen Huang
Keyword(s):  
Graph Representation ◽  
Creative Design ◽  
The Novel ◽  
Kinematic Structure ◽  
Performance Indices ◽  
Topological Graphs ◽  
Systematic Method ◽  
Kinematic Chains ◽  
Challenging Issue ◽  
The Creation

Creation of novel kinematic structures of mechanisms has been a challenging issue which is usually conducted on experience and intuition. This paper, however, proposes a systematic method for the creative design of mechanism-based products and equipments on the basis of corresponding atlas database, and the creative design of an 11-link 2-DOF rode tractor is provided as an example. First, the transformation of the kinematic structure of mechanisms into graph representation is addressed. Then, the complete atlas database of 11-link 2-DOF kinematic chains is established by obtaining all the non-fractionated topological graphs through their contracted graphs and all the fractionated topological graphs through the combination of 1-DOF kinematic chains. Finally, based on the established atlas database, the creation design for the novel mechanisms of 11-link 2-DOF rode tractors is implemented, and all the nine novel feasible mechanisms (including the widely used one reported in literature) which satisfy the proposed performance indices are obtained.

Diaghilev and British Writing

2009 ◽  
Vol 27 (1) ◽  
pp. 65-92
Author(s):  
Susan Jones
Keyword(s):  
Visual Arts ◽  
The Body ◽  
The Novel ◽  
Literary Responses ◽  
Literary Aesthetics ◽  
Ballets Russes ◽  
The Arts ◽  
The Subject ◽  
And Gender ◽  
Opening Up

This article explores the diversity of British literary responses to Diaghilev's project, emphasising the way in which the subject matter and methodologies of Diaghilev's modernism were sometimes unexpectedly echoed in expressions of contemporary British writing. These discussions emerge both in writing about Diaghilev's work, and, more discretely, when references to the Russian Ballet find their way into the creative writing of the period, serving to anchor the texts in a particular cultural milieu or to suggest contemporary aesthetic problems in the domain of literary aesthetics developing in the period. Figures from disparate fields, including literature, music and the visual arts, brought to their criticism of the Ballets Russes their individual perspectives on its aesthetics, helping to consolidate the sense of its importance in contributing to the inter-disciplinary flavour of modernism across the arts. In the field of literature, not only did British writers evaluate the Ballets Russes in terms of their own poetics, their relationship to experimentation in the novel and in drama, they developed an increasing sense of the company's place in dance history, its choreographic innovations offering material for wider discussions, opening up the potential for literary modernism's interest in impersonality and in the ‘unsayable’, discussions of the body, primitivism and gender.

Novel Nanolipoidal Systems for the Management of Skin Cancer

2020 ◽  
Vol 14 (2) ◽  
pp. 108-125
Author(s):  
Apoorva Singh ◽  
Nimisha
Keyword(s):  
Skin Cancer ◽  
Survival Rates ◽  
Cancer Therapeutics ◽  
The Body ◽  
Surgical Removal ◽  
The Novel ◽  
Skin Cancers ◽  
Recent Developments ◽  
Abnormal Cells ◽  
The Stability

: Skin cancer, among the various kinds of cancers, is a type that emerges from skin due to the growth of abnormal cells. These cells are capable of spreading and invading the other parts of the body. The occurrence of non-melanoma and melanoma, which are the major types of skin cancers, has increased over the past decades. Exposure to ultraviolet radiations (UV) is the main associative cause of skin cancer. UV exposure can inactivate tumor suppressor genes while activating various oncogenes. The conventional techniques like surgical removal, chemotherapy and radiation therapy lack the potential for targeting cancer cells and harm the normal cells. However, the novel therapeutics show promising improvements in the effectiveness of treatment, survival rates and better quality of life for patients. Different methodologies are involved in the skin cancer therapeutics for delivering the active ingredients to the target sites. Nano carriers are very efficient as they have the ability to improve the stability of drugs and further enhance their penetration into the tumor cells. The recent developments and research in nanotechnology have entitled several targeting and therapeutic agents to be incorporated into nanoparticles for an enhancive treatment of skin cancer. To protect the research works in the field of nanolipoidal systems various patents have been introduced. Some of the patents acknowledge responsive liposomes for specific targeting, nanocarriers for the delivery or co-delivery of chemotherapeutics, nucleic acids as well as photosensitizers. Further recent patents on the novel delivery systems have also been included here.

scholarly journals Disease Mechanisms and Therapeutic Approaches in C9orf72 ALS-FTD

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 601
Author(s):  
Keith Mayl ◽  
Christopher E. Shaw ◽  
Youn-Bok Lee
Keyword(s):  
The Body ◽  
The Novel ◽  
Therapeutic Approaches ◽  
Gain Of Function ◽  
Pathogenic Mechanisms ◽  
Hexanucleotide Repeat ◽  
Primary Driver ◽  
Hexanucleotide Repeat Expansion ◽  
Expansion Mutation ◽  
Lateral Sclerosis

A hexanucleotide repeat expansion mutation in the first intron of C9orf72 is the most common known genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Since the discovery in 2011, numerous pathogenic mechanisms, including both loss and gain of function, have been proposed. The body of work overall suggests that toxic gain of function arising from bidirectionally transcribed repeat RNA is likely to be the primary driver of disease. In this review, we outline the key pathogenic mechanisms that have been proposed to date and discuss some of the novel therapeutic approaches currently in development.

scholarly journals A constraint graph representation of metamorphic linkages

2011 ◽  
Vol 46 (2) ◽  
pp. 228-238 ◽  
Author(s):  
Duanling Li ◽  
Zhonghai Zhang ◽  
J. Michael McCarthy
Keyword(s):  
Graph Representation ◽  
Constraint Graph

scholarly journals The Embodiment of Insult: A Theory of Biobehavioral Response to Workplace Incivility

2021 ◽  
pp. 014920632198979
Author(s):  
Lilia M. Cortina ◽  
M. Sandy Hershcovis ◽  
Kathryn B. H. Clancy
Keyword(s):  
Behavioral Responses ◽  
Well Being ◽  
Workplace Incivility ◽  
The Body ◽  
Social Connections ◽  
The Novel ◽  
Target Response ◽  
Organizational Life ◽  
New Science ◽  
Broad Theory

This article builds a broad theory to explain how people respond, both biologically and behaviorally, when targeted with incivility in organizations. Central to our theorizing is a multifaceted framework that yields four quadrants of target response: reciprocation, retreat, relationship repair, and recruitment of support. We advance the novel argument that these behaviors not only stem from biological change within the body but also stimulate such change. Behavioral responses that revolve around affiliation and produce positive social connections are most likely to bring biological benefits. However, social and cultural features of an organization can stand in the way of affiliation, especially for employees holding marginalized identities. When incivility persists over time and employees lack access to the resources needed to recover, we theorize, downstream consequences can include harms to their physical health. Like other aspects of organizational life, this biobehavioral theory of incivility response is anything but simple. But it may help explain how seemingly “small” insults can sometimes have large effects, ultimately undermining workforce well-being. It may also suggest novel sites for incivility intervention, focusing on the relational and inclusive side of work. The overarching goal of this article is to motivate new science on workplace incivility, new knowledge, and ultimately, new solutions.

Stresses and Displacements in a Rotating Conical Shell

1943 ◽  
Vol 10 (2) ◽  
pp. A53-A61
Author(s):  
J. L. Meriam
Keyword(s):  
Conical Shell ◽  
Body Force ◽  
Theory Of Elasticity ◽  
Common Type ◽  
The Body ◽  
Surface Loading ◽  
Thin Walled Structures ◽  
Special Cases ◽  
Engineering Problems ◽  
Rotating Conical Shell

Abstract The analysis of shells is an important subdivision of the general theory of elasticity, and its application is useful in the solution of engineering problems involving thin-walled structures. A common type of shell is one which possesses symmetry with respect to an axis of revolution. A theory for such shells has been developed by various investigators (1, 2, 3, 6) and applied to a few simple cases such as the cylindrical, spherical, and conical shapes. Boundary conditions, for the most part, have been simple static ones, and conditions of surface loading have been included in certain special cases. This paper extends the theory of axially symmetrical shells by including the body force of rotation about the axis and applies the results to the rotating conical shell. The analysis follows a pattern established by several investigators (1, 2, 3, 6) and for this reason is abbreviated to a considerable extent. Only where the inclusion of the body force makes elucidation advisable or where a slightly different method of approach is used are the steps presented in more detail.

scholarly journals Interpreting Neuronal Population Activity by Reconstruction: Unified Framework With Application to Hippocampal Place Cells

1998 ◽  
Vol 79 (2) ◽  
pp. 1017-1044 ◽  
Author(s):  
Kechen Zhang ◽  
Iris Ginzburg ◽  
Bruce L. McNaughton ◽  
Terrence J. Sejnowski
Keyword(s):  
Bayesian Methods ◽  
Neuronal Population ◽  
Place Cells ◽  
The Body ◽  
Unified Framework ◽  
Population Activity ◽  
Reconstruction Methods ◽  
Special Cases ◽  
Physical Variables ◽  
The Brain

Zhang, Kechen, Iris Ginzburg, Bruce L. McNaughton, and Terrence J. Sejnowski. Interpreting neuronal population activity by reconstruction: unified framework with application to hippocampal place cells. J. Neurophysiol. 79: 1017–1044, 1998. Physical variables such as the orientation of a line in the visual field or the location of the body in space are coded as activity levels in populations of neurons. Reconstruction or decoding is an inverse problem in which the physical variables are estimated from observed neural activity. Reconstruction is useful first in quantifying how much information about the physical variables is present in the population and, second, in providing insight into how the brain might use distributed representations in solving related computational problems such as visual object recognition and spatial navigation. Two classes of reconstruction methods, namely, probabilistic or Bayesian methods and basis function methods, are discussed. They include important existing methods as special cases, such as population vector coding, optimal linear estimation, and template matching. As a representative example for the reconstruction problem, different methods were applied to multi-electrode spike train data from hippocampal place cells in freely moving rats. The reconstruction accuracy of the trajectories of the rats was compared for the different methods. Bayesian methods were especially accurate when a continuity constraint was enforced, and the best errors were within a factor of two of the information-theoretic limit on how accurate any reconstruction can be and were comparable with the intrinsic experimental errors in position tracking. In addition, the reconstruction analysis uncovered some interesting aspects of place cell activity, such as the tendency for erratic jumps of the reconstructed trajectory when the animal stopped running. In general, the theoretical values of the minimal achievable reconstruction errors quantify how accurately a physical variable is encoded in the neuronal population in the sense of mean square error, regardless of the method used for reading out the information. One related result is that the theoretical accuracy is independent of the width of the Gaussian tuning function only in two dimensions. Finally, all the reconstruction methods considered in this paper can be implemented by a unified neural network architecture, which the brain feasibly could use to solve related problems.

French Women, Italian Art, and Other “Advocates of the Body” in Harriet Beecher Stowe's The Minister's Wooing

2010 ◽  
Vol 83 (1) ◽  
pp. 47-72 ◽  
Author(s):  
Dorothy Z. Baker
Keyword(s):  
Female Body ◽  
The Body ◽  
The Novel ◽  
Religious Paintings ◽  
Italian Art

Displays of sanctified eroticism in The Minister's Wooing reveal Harriet Beecher Stowe's conviction that the body is inherently holy. The author's experience of religious paintings and her observation of French women in Europe deepened her belief that the female body is an instrument of spirituality, as can be traced in the novel.

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