Force–Deflection Modeling for Generalized Origami Waterbomb-Base Mechanisms

2015 ◽  
Vol 82 (8) ◽  
Author(s):  
Brandon H. Hanna ◽  
Spencer P. Magleby ◽  
Robert J. Lang ◽  
Larry L. Howell
Keyword(s):  
Potential Energy ◽  
Potential Application ◽  
Central Vertex ◽  
Panel Size ◽  
Single Vertex ◽  
Similarities And Differences ◽  
Bistable Mechanism ◽  
Special Case

The origami waterbomb base (WB) is a single-vertex bistable mechanism that can be generalized to accommodate various geometric, kinematic, and kinetic needs. The traditional WB consists of a square sheet that has four mountain folds alternating with five valley folds (eight folds total) around the vertex in the center of the sheet. This special case mechanism can be generalized to create two classes of waterbomb-base-type mechanisms that allow greater flexibility for potential application. The generalized WB maintains the pattern of alternating mountain and valley folds around a central vertex but it is not restricted to eight total folds. The split-fold waterbomb base (SFWB) is made by splitting each fold of a general WB into two “half folds” of the same variety as the parent fold. This study develops kinematic, potential energy, and force–deflection models for the rigid-foldable, developable, symmetric cases of the generalized WB and the SFWB, and investigates the relative effects of numbers of folds and split-fold panel size, on device behavior. The effect of selected key parameters is evaluated, and equations are provided to enable the exploration of other important parameters that may be of interest in the design and analysis of specific mechanisms. The similarities and differences between the two general forms are discussed, including tunability of the bistable and force–deflection behavior of each.

Aspects of neurological decompression illness: A view from Bethesda

1995 ◽  
Vol 81 (2) ◽  
pp. 120-126
Author(s):  
J R Broome
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Drug Therapy ◽  
Potential Application ◽  
Oxygen Therapy ◽  
Spinal Cord Trauma ◽  
Decompression Illness ◽  
Cord Injury ◽  
Similarities And Differences

AbstractA minority of divers with neurological decompression illness (DCI) fail to improve with recompression treatment. This is particularly seen in cases where features of severe spinal cord injury develop soon after surfacing. Haemorrhage into the spinal cord is implicated in the pathogenesis of these cases, and evidence is presented that supports the view that the bleeding coincides with shrinkage of autochthonous bubbles. The role ofhyperbaric oxygen therapy in the treatment of spinal cord DCI is discussed with reference to posssible benefit in ischaernia-reperfusion (I-R) injury. Similarities and differences between thetissue injury of dysbaric and conventional spinal cord injury are outlined. The implications of advances in drug therapy for conventional spinal cord trauma are considered in the context of their potential application to treat neurological DCI.

scholarly journals The status of pelvic floor muscle training for women

2013 ◽  
Vol 4 (6) ◽  
pp. 419
Author(s):  
Andrea Marques ◽  
Lynn Stothers ◽  
Andrew Macnab
Keyword(s):  
Pelvic Floor ◽  
Nous Avons ◽  
Potential Application ◽  
New Technologies ◽  
Pelvic Floor Muscle Training ◽  
Pelvic Floor Muscle ◽  
Muscle Training ◽  
The Status ◽  
Similarities And Differences ◽  
Muscle Fitness

There is no consensus on the amount of exercise necessary toimprove pelvic floor muscle (PFM) function. We reviewed thepathophysiology of PFM dysfunction and the evolution of PFMtraining regimens since Kegel introduced the concept of pelvic floorawareness and the benefits of strength. This paper also describesthe similarities and differences between PFM and other musculargroups, reviews the physiology of muscle contraction and principlesof muscle fitness and exercise benefits and presents the rangeof protocols designed to strengthen the PFM and improve function.We also discuss the potential application of new technologyand methodologies. The design of PFM training logically requiresmultiple factors to be considered in each patient. Research thatdefines measures to objectively quantify the degree of dysfunctionand the efficacy of training would be beneficial. The applicationof new technologies may help this process.Il n’existe aucun consensus concernant la quantité d’exercicerequis pour améliorer la fonction du muscle du plancher pelvien(MPP). Nous avons examiné la physiopathologie d’un mauvaisfonctionnement du MPP et l’évolution des plans d’entraînement dece muscle depuis que Kegel a introduit le concept de la prise deconscience du MPP et les avantages de son renforcement. L’articledécrit également les similitudes et les différences entre le MPP etd’autres groupes musculaires, passe en revue la physiologie descontractions musculaires et les principes de bon fonctionnementmusculaire et les avantages liés à l’exercice. Nous présentons aussidivers protocoles visant à renforcer le MPP et à en améliorer lefonctionnement, ainsi que l’application potentielle de nouvellestechnologies et méthodologies. Le plan d’entraînement du MPPnécessite en toute logique la prise en compte de multiples facteursselon les patients. Des études cherchant à définir les mesures àutiliser pour quantifier de manière objective le niveau de dysfonctionet l’efficacité de l’entraînement seraient utiles. L’application denouvelles technologies pourrait contribuer à cet objectif.

scholarly journals FOLDING EQUILATERAL PLANE GRAPHS

2013 ◽  
Vol 23 (02) ◽  
pp. 75-92 ◽  
Author(s):  
ZACHARY ABEL ◽  
ERIK D. DEMAINE ◽  
MARTIN L. DEMAINE ◽  
SARAH EISENSTAT ◽  
JAYSON LYNCH ◽  
...  
Keyword(s):  
Plane Graph ◽  
Analogous Problem ◽  
Central Vertex ◽  
Polyhedral Complex ◽  
Plane Graphs ◽  
Single Vertex ◽  
Np Completeness ◽  
Np Complete ◽  
Polyhedral Manifold

We consider two types of folding applied to equilateral plane graph linkages. First, under continuous folding motions, we show how to reconfigure any linear equilateral tree (lying on a line) into a canonical configuration. By contrast, it is known that such reconfiguration is not always possible for linear (nonequilateral) trees and for (nonlinear) equilateral trees. Second, under instantaneous folding motions, we show that an equilateral plane graph has a noncrossing linear folded state if and only if it is bipartite. Furthermore, we show that the equilateral constraint is necessary for this result, by proving that it is strongly NP-complete to decide whether a (nonequilateral) plane graph has a linear folded state. Equivalently, we show strong NP-completeness of deciding whether an abstract metric polyhedral complex with one central vertex has a noncrossing flat folded state. By contrast, the analogous problem for a polyhedral manifold with one central vertex (single-vertex origami) is only weakly NP-complete.

RECENT DEVELOPMENT IN THE STUDY OF SN2 REACTIONS AT HETEROATOMS AND ION PAIR SYSTEMS

2006 ◽  
Vol 05 (01) ◽  
pp. 121-140 ◽  
Author(s):  
YI REN ◽  
SAN-YAN CHU
Keyword(s):  
Potential Energy ◽  
Potential Energy Surfaces ◽  
Ion Pair ◽  
Present Review ◽  
Theoretical Studies ◽  
Sn2 Reactions ◽  
Energy Relationships ◽  
Similarities And Differences ◽  
Energy Surfaces ◽  
Experimental And Theoretical Studies

Present review outlines the experimental and theoretical studies on the SN 2 reactions at heteroatoms ( N , O and S ) and ion pair systems in recent years, especially introduce research carried out at our group in detail. The similarities and differences between SN 2 at heteroatoms and at carbon are discussed. Some new structure–energy relationships were proposed. The accuracy of various theoretical schemes for calculating potential energy surfaces has been assessed.

scholarly journals On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations

2017 ◽  
Vol 28 (2) ◽  
pp. 3-9
Author(s):  
Ali M. Rushdi Ali M. Rushdi
Keyword(s):  
Inverse Problem ◽  
Boolean Function ◽  
Curve Fitting ◽  
Boolean Functions ◽  
Consistency Condition ◽  
Similarities And Differences ◽  
Special Case

This paper explores the similarities and differences between two prominent problems in the mathematics of Boolean functions. The first of these problems is that of Boolean curve fitting (BCF), also known as Boolean interpolation, which deals with constructing a curve 𝑧 = 𝑓(𝐗) through a number of points z𝑘 = 𝑓(𝐗𝑘 ) where 𝑘 = 1,2, … , 𝑚. The second problem is the Inverse Problem of Boolean equations (IPBE), which constructs a Boolean function whose zeroes are all known. While the problem of Boolean curve fitting might require a consistency condition for its solution, the Inverse Problem of Boolean equations might use a consistency condition as an input. Without a consistency condition, the Inverse Problem of Boolean equations can be viewed as a special case of the problem of Boolean curve fitting, provided the specified points z𝑘 are the only zeros of 𝑓(𝐗). Our findings are illustrated via a detailed typical example.

Constitutive Laws for Ceramics Exhibiting Stress-Induced Martensitic Transformation

1986 ◽  
Vol 78 ◽  
Author(s):  
John C. Lambropoulos
Keyword(s):  
Potential Energy ◽  
Volume Concentration ◽  
Inelastic Strain ◽  
Internal Variable ◽  
Constitutive Laws ◽  
Constitutive Law ◽  
Internal Variables ◽  
Strain Rates ◽  
Applied Stresses ◽  
Special Case

ABSTRACTThe theory of internal variables is used in order to develop multiaxial constitutive laws for ceramics undergoing martensitic stress-assisted transformation, such as partially stabilized zirconia or A12O3-ZrO2. The internal variable is identified with the volume concentration of transformed particles, and we assume that transformation occurs so that the change in potential energy due to the transformation is maximized. When the rate of transformation depends on the applied stresses only through the corresponding change in potential energy, it is shown that the inelastic strain rates are along the normal of a stress function in stress space. The constitutive law depends on all three stress invariants. We further discuss specific stress environments such as crack tip fields, the special case of homogeneous transforming particle distribution, and conditions under which normality is not obeyed.

Extreme self-sacrifice beyond fusion: Moral expansiveness and the special case of allyship

2018 ◽  
Vol 41 ◽  
Author(s):  
Daniel Crimston ◽  
Matthew J. Hornsey
Keyword(s):  
General Theory ◽  
Biological Markers ◽  
Natural Environment ◽  
Relevant Dimension ◽  
Special Case

AbstractAs a general theory of extreme self-sacrifice, Whitehouse's article misses one relevant dimension: people's willingness to fight and die in support of entities not bound by biological markers or ancestral kinship (allyship). We discuss research on moral expansiveness, which highlights individuals’ capacity to self-sacrifice for targets that lie outside traditional in-group markers, including racial out-groups, animals, and the natural environment.

Determination of the phase structure of polymerblends by electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 492-493
Author(s):  
Dr. G. Kaemof
Keyword(s):  
Screw Extruder ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Single Screw Extruder ◽  
Transmission Electron ◽  
The Matrix ◽  
Twin Screw ◽  
Special Case ◽  
Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

Orosensory Perception, Speech Production, and Deafness

1973 ◽  
Vol 16 (2) ◽  
pp. 257-266 ◽  
Author(s):  
Milo E. Bishop ◽  
Robert L. Ringel ◽  
Arthur S. House
Keyword(s):  
High School ◽  
Speech Production ◽  
Poor Performance ◽  
Normal Hearing ◽  
The Other ◽  
Functional Disorders ◽  
Form Discrimination ◽  
School Subjects ◽  
Oral Form ◽  
Similarities And Differences

The oral form-discrimination abilities of 18 orally educated and oriented deaf high school subjects were determined and compared to those of manually educated and oriented deaf subjects and normal-hearing subjects. The similarities and differences among the responses of the three groups were discussed and then compared to responses elicited from subjects with functional disorders of articulation. In general, the discrimination scores separated the manual deaf from the other two groups, particularly when differences in form shapes were involved in the test. The implications of the results for theories relating orosensory-discrimination abilities are discussed. It is postulated that, while a failure in oroperceptual functioning may lead to disorders of articulation, a failure to use the oral mechanism for speech activities, even in persons with normal orosensory capabilities, may result in poor performance on oroperceptual tasks.

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