Synthesizing Functional Mechanisms From a Link Soup1

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Pouya Tavousi ◽  
Kazem Kazerounian ◽  
Horea Ilies

The synthesis of functional molecular linkages is constrained by difficulties in fabricating nanolinks of arbitrary shapes and sizes. Thus, classical mechanism synthesis methods, which assume the ability to manufacture any designed links, cannot provide a systematic process for assembling such linkages. We propose a new approach to building functional mechanisms with prescribed mobility by using only elements from a predefined “link soup.” First, we enumerate an exhaustive set of topologies, while employing divide-and-conquer algorithms to control the generation and elimination of redundant topologies. Then, we construct the linkage arrangements for each valid topology. Finally, we output a set of feasible geometries through a positional analysis step that minimizes the error associated with closure of the loops in the linkage while avoiding geometric interference. The proposed systematic approach outputs the ATLAS of candidate mechanisms, which can be further processed for downstream applications. The resulting synthesis procedure is the first of its kind that is capable of synthesizing functional linkages with prescribed mobility constructed from a soup of primitive entities.

Author(s):  
Pouya Tavousi ◽  
Kazem Kazerounian ◽  
Horea Ilies

The synthesis of functional molecular linkages is constrained by difficulties in fabricating nano-links of arbitrary shapes and sizes. However, the classical mechanism synthesis methods, which assume the ability to manufacture any designed links, do not provide a systematic synthesis process for molecular linkages. We propose a new approach to build functional mechanisms with prescribed mobility by only using elements from a predefined link soup. First, we enumerate an exhaustive set of topologies, while employing divide-and-conquer algorithms to control the generation and elimination of redundant topologies. Then, we construct the linkage arrangements for each valid topology. Finally, we output a set of feasible geometries through a positional analysis step that minimizes the error associated with closure of the loops in the linkage while avoiding geometric interference. The proposed systematic approach outputs the ATLAS of candidate mechanisms, which can be further processed for downstream applications. The resulting synthesis procedure is the first of its kind that is capable of synthesizing functional linkages with prescribed mobility constructed from a soup of primitive entities.


Author(s):  
Todd J. Furlong ◽  
Judy M. Vance ◽  
Pierre M. Larochelle

Abstract This paper presents a new approach to using virtual reality (VR) to design spherical mechanisms. VR provides a three dimensional design space where a designer can input design positions using a combination of hand gestures and motions and view the resultant mechanism in stereo using natural head movement to change the viewpoint. Because of the three dimensional nature of the design and verification of spherical mechanisms, VR is examined as a new design interface in this research. In addition to providing a VR environment for design, the research presented in this paper has focused on developing a “design in context” approach to spherical mechanism design. Previous design methods have involved placing coordinate frames along the surface of a constraint sphere. The new “design in context” approach allows a designer to freely place geometric models of movable objects inside an environment consisting of fixed objects. The fixed objects could either act as a base for a mechanism or be potential sources of interference with the motion of the mechanism. This approach allows a designer to perform kinematic synthesis of a mechanism while giving consideration to the interaction of that mechanism with its application environment.


2020 ◽  
pp. 9-43
Author(s):  
Rosamond Rhodes

The Trusted Doctor: Medical Ethics and Professionalism rejects the well-entrenched views of medical ethics as everyday ethics or common morality applied to medicine. This chapter lays the foundation for the original account of medical ethics that follows in the book’s succeeding chapters. By presenting vivid examples and general arguments the author demonstrates ways in which the ethics of medicine is distinct and different from common morality. The chapter discusses the most popular common morality views, namely, the four principles approach expounded by Tom Beauchamp and James Childress in Principles of Biomedical Ethics and the ten rules approach presented by Bernard Gert, Charles Culver, and K. Danner Clouser in Bioethics: A Systematic Approach by presenting arguments that challenge their applicability to medical practice. A chart identifies some stark differences between the common morality approach and good medical practice and shows how everyday ethics is incompatible with medical professionalism.


2019 ◽  
Vol 47 (17) ◽  
pp. e101-e101 ◽  
Author(s):  
Boris Breiner ◽  
Kerr Johnson ◽  
Magdalena Stolarek ◽  
Ana-Luisa Silva ◽  
Aurel Negrea ◽  
...  

AbstractA new approach to single-molecule DNA sequencing in which dNTPs, released by pyrophosphorolysis from the strand to be sequenced, are captured in microdroplets and read directly could have substantial advantages over current sequence-by-synthesis methods; however, there is no existing method sensitive enough to detect a single nucleotide in a microdroplet. We have developed a method for dNTP detection based on an enzymatic two-stage reaction which produces a robust fluorescent signal that is easy to detect and process. By taking advantage of the inherent specificity of DNA polymerases and ligases, coupled with volume restriction in microdroplets, this method allows us to simultaneously detect the presence of and distinguish between, the four natural dNTPs at the single-molecule level, with negligible cross-talk.


Author(s):  
K.F. Fox ◽  
B.A. Popescu

Quality assurance (QA) in echocardiography is the systematic process of ensuring that information sent out by echo laboratories is timely, appropriate, and accurate. All aspects of a service need to be continuously monitored and optimized if quality is to be maintained and furthermore improved.Particular focus is needed on reporting and measurement with continuous checking for reporting errors and assessment of measurement variability.A systematic QA programme needs to be an essential part of any echo laboratory. Life-determining clinical decisions may depend on it. In this chapter we describe the background to QA, current evidence and guidelines, and a systematic approach to QA.


2020 ◽  
Vol 9 (2) ◽  
pp. 67-80 ◽  
Author(s):  
Ida Fischer ◽  
Catherine Milton ◽  
Heather Wallace

Abstract The efficient management of the continuously increasing number of chemical substances used in today’s society is assuming greater importance than ever before. Toxicity testing plays a key role in the regulatory decisions of agencies and governments that aim to protect the public and the environment from the potentially harmful or adverse effects of these multitudinous chemicals. Therefore, there is a critical need for reliable toxicity-testing methods to identify, assess and interpret the hazardous properties of any substance. Traditionally, toxicity-testing approaches have been based on studies in experimental animals. However, in the last 20 years, there has been increasing concern regarding the sustainability of these methodologies. This has created a real need for the development of new approach methodologies (NAMs) that satisfy the regulatory requirements and are acceptable and affordable to society. Numerous initiatives have been launched worldwide in attempts to address this critical need. However, although the science to support this is now available, the legislation and the pace of NAMs acceptance is lagging behind. This review will consider some of the various initiatives in Europe to identify NAMs to replace or refine the current toxicity-testing methods for pharmaceuticals. This paper also presents a novel systematic approach to support the desired toxicity-testing methodologies that the 21st century deserves.


Author(s):  
Chien-Lin Huang ◽  
Jia-Ching Wang ◽  
Bin Ma

This paper presents an ensemble-based speaker recognition using unsupervised data selection. Ensemble learning is a type of machine learning that applies a combination of several weak learners to achieve an improved performance than a single learner. A speech utterance is divided into several subsets based on its acoustic characteristics using unsupervised data selection methods. The ensemble classifiers are then trained with these non-overlapping subsets of speech data to improve the recognition accuracy. This new approach has two advantages. First, without any auxiliary information, we use ensemble classifiers based on unsupervised data selection to make use of different acoustic characteristics of speech data. Second, in ensemble classifiers, we apply the divide-and-conquer strategy to avoid a local optimization in the training of a single classifier. Our experiments on the 2010 and 2008 NIST Speaker Recognition Evaluation datasets show that using ensemble classifiers yields a significant performance gain.


2011 ◽  
Vol 90 (4) ◽  
pp. 271-291 ◽  
Author(s):  
K. Leszczynska ◽  
J. Boreham ◽  
S. Boreham

AbstractAlthough micromorphological terminology has been evolving since 1960, there have been few attempts to create a systematic approach to the description of thin-sections which would serve as a guiding tool for inexperienced researchers, students, and all new to the field of micromorphology. In this paper we present a novel, decision tree based systematic approach for thin-section description. This new approach attempts to unify micromorphological descriptions of Quaternary deposits, regardless of the character of the deposit and the purpose of the analysis.In this research project, named ‘Hidden Ice Worlds’, the micromorphology of an 8 m thick sequence of periglacially disturbed deposits from the Royal Oak Pit, Danbury hill, Essex, UK is described. This sequence is situated on the eastern side of Danbury hill, at c. 50 m OD. Based on micromorphological analyses, a new hypothesis for the evolution of this sequence is presented. Multiple phases of physical reworking associated with freezing and thawing of the deposit, subsequent to Elsterian (Anglian) glaciation (480-420 ka BP) is proposed as the main process responsible for the evolution of the sequence. As periglacially derived deposits are usually removed from such elevated locations on hill' slopes, inversion of the topography is proposed as a necessary factor for the formation and preservation of the sequence described in this atypical location.


2014 ◽  
Vol 12 (3) ◽  
pp. 663-676
Author(s):  
Roy Germano

New digital video technologies are transforming how people everywhere document, publish, and consume information. As knowledge production becomes increasingly oriented towards digital/visual modes of expression, scholars will need new approaches for conducting and publishing research. The purpose of this article is to advance a systematic approach to scholarship calledanalytic filmmaking.I argue that when filming and editing are guided by rigorous social scientific standards, digital video can be a compelling medium for illustrating causal processes, communicating theory-driven explanations, and presenting new empirical findings. I furthermore argue that analytic films offer policymakers and the public an effective way to glean insights from and engage with scholarly research. Throughout the article I draw on examples from my work to demonstrate the principles of analytic filmmaking in practice and to point out how analytic films complement written scholarship.


Author(s):  
Nilesh D. Mankame ◽  
G. K. Ananthasuresh

Abstract This paper presents a line element based approach to the synthesis of electrothermally actuated compliant (ETC) mechanisms. A line element is a one-dimensional model of the electrical, thermal and elastic behavior of a beam-like continuum. In contrast to topology synthesis of ETC mechanisms by a continuum element based approach, the line element based approach offers significant conceptual and practical advantages. The line element approach allows for accurate modeling of surface heat transfer in a straightforward manner. Moreover, this approach results in clean geometries that are easy to fabricate. The line element based ETC mechanism synthesis procedure is used to study the influence of the direction of output and the electrical and thermal resistance of the workpiece on the resulting optimal topology. Solutions obtained from this procedure are compared with results from continuum based optimal synthesis procedures as well as intuitive designs reported in literature. The ability of the procedure to generate non-intuitive topologies is also demonstrated through design examples.


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