Construction simulation analysis of 120m continuous rigid frame bridge based on Midas Civil
Shi, Jing-xian; Ran, Zhi-hong
2018-03-01
In this paper, a three-dimensional finite element model of a continuous rigid frame bridge with a main span of 120m is established by the simulation and analysis of Midas Civil software. The deflection and stress of the main beam in each construction stage of continuous beam bridge are simulated and analyzed, which provides a reliable technical guarantee for the safe construction of the bridge.
Rigid Motion and Adapted Frames
Lyle, Stephen N.
The aim here is to describe the rigid motion of a continuous medium in special and general relativity. Section 7.1 defines a rigid rod in special relativity, and Sect. 7.2 shows the link with the space coordinates of a certain kind of accelerating frame in flat spacetimes. Section 7.3 then sets up a notation for describing the arbitrary smooth motion of a continuous medium in general curved spacetimes, defining the proper metric of such a medium. Section 7.4 singles out rigid motions and shows that the rod in Sect. 7.1 undergoes rigid motion in the more generally defined sense. Section 7.5 defines a rate of strain tensor for a continuous medium in general relativity and reformulates the rigidity criterion. Section 7.6 aims to classify all possible rigid motions in special relativity, reemphasizing the link with semi-Euclidean frames adapted to accelerating observers in special relativity. Then, Sects. 7.7 and 7.8 describe rigid motion without rotation and rigid rotation, respectively. Along the way we introduce the notion of Fermi-Walker transport and discuss its relevance for rigid motions. Section 7.9 brings together all the above themes in an account of a recent generalization of the notion of uniform acceleration, thereby characterizing a wide class of rigid motions.
Discretization of continuous frame
Indian Academy of Sciences (India)
other known continuous frames. Finally, we state and prove the assertions of the stability of perturbation in this concept. Keywords. Bounded operator; Hilbert space; continuous frame; atomic resolution of identity. 1. Introduction and preliminaries. As we know frames are more flexible tools to convey information than bases, ...
Discretization of continuous frame
Indian Academy of Sciences (India)
Home; Journals; Proceedings – Mathematical Sciences; Volume 122; Issue 2 ... In this paper we consider the notion of continuous frame of subspaces and define a new concept of continuous frame, entitled continuous atomic resolution of identity, for arbitrary Hilbert space H which has a countable reconstruction formula.
Continuous Shearlet Tight Frames
Grohs, Philipp
2010-10-22
Based on the shearlet transform we present a general construction of continuous tight frames for L2(ℝ2) from any sufficiently smooth function with anisotropic moments. This includes for example compactly supported systems, piecewise polynomial systems, or both. From our earlier results in Grohs (Technical report, KAUST, 2009) it follows that these systems enjoy the same desirable approximation properties for directional data as the previous bandlimited and very specific constructions due to Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009). We also show that the representation formulas we derive are in a sense optimal for the shearlet transform. © 2010 Springer Science+Business Media, LLC.
Dynamic response and stability of semi-rigid frames
Abu-Yasein, Omar Ali
This dissertation presents a method to determine the load capacity as well as end member forces and deformations of frames with partial rigid joint connections by using the direct stiffness method. The connections are modeled as rotational springs attached at the ends of framed members. The lumped mass method, which is an approximate method, and the distributed mass method, which is an exact method, are also presented to compute the natural frequency of frames. The effects of the axial forces and the flexibility of joint connections are both included. Furthermore, the time-dependent response of semi-rigid frames subjected to periodic axial forces is formulated. The harmonic function is approximated by dividing the periodic function into n intervals and the periodic axial forces are evaluated at each time interval as constant forces using 'piecewise approximation'. The regions of instability of frames with different joint stiffness were determined using the characteristic equation method. The time-dependent part of the differential equation for free vibration of a framed member subjected to a harmonic force can be written in the form of the Mathieu-Hill equation where all characteristics of the Mathieu-Hill equation solutions can be used to determine the boundaries of instability regions.
Post-Newtonian conservation laws in rigid quasilocal frames
International Nuclear Information System (INIS)
McGrath, Paul L; Chanona, Melanie; Epp, Richard J; Mann, Robert B; Koop, Michael J
2014-01-01
In recent work we constructed completely general conservation laws for energy (McGrath et al 2012 Class. Quantum Grav. 29 215012) and linear and angular momentum (Epp et al 2013 Class. Quantum Grav. 30 195019) of extended systems in general relativity based on the notion of a rigid quasilocal frame (RQF). We argued at a fundamental level that these RQF conservation laws are superior to conservation laws based on the local stress–energy–momentum tensor of matter because (1) they do not rely on spacetime symmetries and (2) they properly account for both matter and gravitational effects. Moreover, they provide simple, exact, operational expressions for fluxes of gravitational energy and linear and angular momentum. In this paper we derive the form of these laws in a general first post-Newtonian (1PN) approximation, and then apply these approximate laws to the problem of gravitational tidal interactions. We obtain formulas for tidal heating and tidal torque that agree with the literature, but without resorting to the use of pseudotensors. We describe the physical mechanism of these tidal interactions not in the traditional terms of a Newtonian gravitational force, but in terms of a much simpler and universal mechanism that is an exact, quasilocal manifestation of the equivalence principle in general relativity. As concrete examples, we look at the tidal heating of Jupiter’s moon Io and angular momentum transfer in the Earth–Moon system that causes a gradual spin-down of the Earth and recession of the Moon. In both examples we find agreement with observation. (paper)
Multipliers for continuous frames in Hilbert spaces
International Nuclear Information System (INIS)
Balazs, P; Bayer, D; Rahimi, A
2012-01-01
In this paper, we examine the general theory of continuous frame multipliers in Hilbert space. These operators are a generalization of the widely used notion of (discrete) frame multipliers. Well-known examples include anti-Wick operators, STFT multipliers or Calderón–Toeplitz operators. Due to the possible peculiarities of the underlying measure spaces, continuous frames do not behave quite as their discrete counterparts. Nonetheless, many results similar to the discrete case are proven for continuous frame multipliers as well, for instance compactness and Schatten-class properties. Furthermore, the concepts of controlled and weighted frames are transferred to the continuous setting. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)
Connections rigidity effect on probability of fracture in steel moment frames
Directory of Open Access Journals (Sweden)
Gholamreza Abdollahzadeh
2017-08-01
Full Text Available Connections in steel moment frames are idealized in full pinned and full rigid conditions. Because with this assumption, in spite of real behavior of connection, real story drifts are less anticipated and maybe frame is designed without performance of bracing. There are several methods for modeling actual behavior of semi rigid connections. In this method a connection with certain rigidity is modeled by a rotational spring with corresponding stiffness. This stiffness is achieved by certain formula. In other words, each percent of rigidity corresponds to one rotational spring stiffness. In this research in order to evaluate the real behavior of connection in analysis and designing process and fracture probability one frame including four stories and one bay with three types of connection has been modeled and designed in ETABS. Each model has an individual rigidity which is equal to 10, 75 and 90 percent. With respect to maximum drift and different PGA in roof, probabilities of low, medium, high and complete fracture were calculated. For this purpose, with applying different PGA to modeled frames, amounts of drift in the roof are achieved. Then these values are compared with given values in American code. Finally, investigation showed that when rigidity in frame connections increases, the probability of frame fracture decreases. In other words, fully rigid assumption of connection in analysis process leads to decreasing in real probability of fracture in frames which is a noticeable risk in building designing processes.
International Nuclear Information System (INIS)
Guerra Romero, I.; Fernandez Majo, M. C.; Valdes, A. J.
2010-01-01
In this paper many bibliographic references have been analyses which deal on the importance of the buckling in rigid frames, and many versions of it, have been got. About 70 frames have been analysed by the authors and they have found that it is advisable to consider the bucking in the design of frames beams. (Author) 30 refs.
Behaviour and Modelling of Semi-rigid Structural Frame Systems ...
African Journals Online (AJOL)
The computer software ABAQUS is used. Experimental investigations were designed in order to evaluate frame load-deflection characteristics, joint local rotations, failure modes, and the contribution of end-plates and bolt connectors to the joint rotations. Theoretical results of frame load-deflection characteristics predicted ...
Directory of Open Access Journals (Sweden)
Talat Körpınar
2012-01-01
Full Text Available In this paper, we study spacelike biharmonic slant helices according to Bishop frame in the Lorentzian group of rigid motions E(1,1. We characterize the spacelike biharmonic slant helices in terms of their curvatures in the Lorentzian group of rigid motions E(1,1. Finally, we obtain parametric equations of spacelike biharmonic slant helices according to Bishop frame in the Lorentzian group of rigid motions E(1,1.
Aboumoussa, Walid
2014-01-01
Structures placed on hillsides often present a number of challenges and a limited number of economical choices for site design. An option sometimes employed is to use the building frame as a retaining element, comprising a Rigidly Framed Earth Retaining Structure (RFERS). The relationship between temperature and earth pressure acting on RFERS, is explored in this monograph through a 4.5 year monitoring program of a heavily instrumented in service structure. The data indicated that the coefficient of earth pressure behind the monitored RFERS had a strong linear correlation with temperature. The study also revealed that thermal cycles, rather than lateral earth pressure, were the cause of failure in many structural elements. The book demonstrates that depending on the relative stiffness of the retained soil mass and that of the structural frame, the developed lateral earth pressure, during thermal expansion, can reach magnitudes several times larger than those determined using classical earth pressure theories....
Directory of Open Access Journals (Sweden)
Jihong Ye
2017-07-01
Full Text Available In this paper, a simple and effective numerical approach is presented on the basis of the Member Discrete Element Method (MDEM to investigate static and dynamic responses of steel frames with semi-rigid joints. In the MDEM, structures are discretized into a set of finite rigid particles. The motion equation of each particle is solved by the central difference method and two adjacent arbitrarily particles are connected by the contact constitutive model. The above characteristics means that the MDEM is able to naturally handle structural geometric nonlinearity and fracture. Meanwhile, the computational framework of static analysis is consistent with that of dynamic analysis, except the determination of damping. A virtual spring element with two particles but without actual mass and length is used to simulate the mechanical behaviors of semi-rigid joints. The spring element is not directly involved in the calculation, but is employed only to modify the stiffness coefficients of contact elements at the semi-rigid connections. Based on the above-mentioned concept, the modified formula of the contact element stiffness with consideration of semi-rigid connections is deduced. The Richard-Abbort four-parameter model and independent hardening model are further introduced accordingly to accurately capture the nonlinearity and hysteresis performance of semi-rigid connections. Finally, the numerical approach proposed is verified by complex behaviors of steel frames with semi-rigid connections such as geometric nonlinearity, snap-through buckling, dynamic responses and fracture. The comparison of static and dynamic responses obtained using the modified MDEM and those of the published studies illustrates that the modified MDEM can simulate the mechanical behaviors of semi-rigid connections simply and directly, and can accurately effectively capture the linear and nonlinear behaviors of semi-rigid connections under static and dynamic loading. Some conclusions
Directory of Open Access Journals (Sweden)
Ravi Kumar Reddy, C.
2014-01-01
Full Text Available This paper presents the effect of rigidity of plinth beam on a model building frame supported by pile groups embedded in cohesionless soil (sand through the results of static vertical load tests. The effect of rigidity of plinth beam on displacements and rotation at the column base and also shears and bending moments in the building frame were investigated. In the analytical model, soil nonlinearity in the axial direction is characterized by nonlinear vertical springs along the length of the pile (t-z curves and at the tip of the pile (Q-z curves while in the lateral direction by the p-y curves. Results revealed that, shear force and bending moment values which were back calculated from the experimental results, showed considerable reduction with the reduction of the rigidity of the plinth beam. The response of the frame from the experimental results is in good agreement with that obtained by the nonlinear finite element analysis.
On the Gabor frame set for compactly supported continuous functions
DEFF Research Database (Denmark)
Christensen, Ole; Kim, Hong Oh; Kim, Rae Young
2016-01-01
We identify a class of continuous compactly supported functions for which the known part of the Gabor frame set can be extended. At least for functions with support on an interval of length two, the curve determining the set touches the known obstructions. Easy verifiable sufficient conditions...... for a function to belong to the class are derived, and it is shown that the B-splines BN, N≥2, and certain ‘continuous and truncated’ versions of several classical functions (e.g., the Gaussian and the two-sided exponential function) belong to the class. The sufficient conditions for the frame property...
Osseous adaptation to continuous loading of rigid endosseous implants
Roberts, W. E.; Smith, R. K.; Mozsary, P. G.; Zilberman, Y.; Smith, R. S.
1984-01-01
The effect of loading on etched Ti implants in the femurs of young (3 mo) and adult (6 mo) rabbits is investigated experimentally. The results are presented in photographs, fluorescence and polarization micrographs, radiographs, and drawings and discussed. Implantation is followed by formation of coarse woven bone within 3 d and mature lamellar bone by 6 wks, with nonspecific subperiosteal bony hypertrophy in the young rabbits only. Spring loading at 100 g produces spontaneous spiral-type fractures when applied immediately, but the implants remain rigid when loads are applied after 6-12 wks of healing. The mechanisms of bone formation involved are examined, and the potential of endosseous implants as anchors in orthodontics or dentofacial-orthopedics is confirmed.
On the Gabor frame set for compactly supported continuous functions
Directory of Open Access Journals (Sweden)
Ole Christensen
2016-03-01
Full Text Available Abstract We identify a class of continuous compactly supported functions for which the known part of the Gabor frame set can be extended. At least for functions with support on an interval of length two, the curve determining the set touches the known obstructions. Easy verifiable sufficient conditions for a function to belong to the class are derived, and it is shown that the B-splines B N $B_{N}$ , N ≥ 2 $N\\ge2$ , and certain ‘continuous and truncated’ versions of several classical functions (e.g., the Gaussian and the two-sided exponential function belong to the class. The sufficient conditions for the frame property guarantees the existence of a dual window with a prescribed size of the support.
open-quotes Metaclose quotes-rigid motions and frames of reference
International Nuclear Information System (INIS)
Bel, L.; Llosa, J.
1995-01-01
We define the open-quotes metaclose quotes-rigid motions as particular classes of time-like congruences which are solutions of intrinsically defined partial differential equations that generalize Born's conditions. We consider in particular two hierarchies of such congruences. The first one is a geometrically motivated direct generalization of the symmetry concept inherent in Born congruences. The second one is an indirect generalization based on the conditions which guarantee the existence of a particular class of adapted coordinates of space, named quo-harmonic coordinates, whose definition is akin to the definition of harmonic coordinates but which differs from it in an essential point
Heavy laminated timber frame with rigid three-dimensional beam-to-column connections
Czech Academy of Sciences Publication Activity Database
Kasal, B.; Guindos, P.; Polocoser, T.; Heiduschke, A.; Urushadze, Shota; Pospíšil, Stanislav
2014-01-01
Roč. 28, č. 6 (2014) ISSN 0887-3828 Institutional support: RVO:68378297 Keywords : seismic performance * timber frame * synthetic seismic excitation Subject RIV: JM - Building Engineering Impact factor: 0.631, year: 2014 http://ascelibrary.org/doi/abs/10.1061/(ASCE)CF.1943-5509.0000594
International Nuclear Information System (INIS)
McCoy, M. L.; Moradi, R.; Lankarani, H. M.
2011-01-01
Agricultural and construction equipment are commonly implemented with rectangular tubing in their structural frame designs. A typical joining method to fabricate these frames is by welding and the use of ancillary structural plating at the connections. This aids two continuous members to pass through an intersection point of the frame with some degree of connectivity, but the connections are highly unbalanced as the tubing centroids exhibit asymmetry. Due to the practice of welded continuous member frame intersections in current agricultural equipment designs, a conviction may exist that welded continuous member frames are superior in structural strength over that of structural frame intersections implementing welded non-continuous members where the tubing centroids lie within two planes of symmetry, a connection design that would likely fabricating a more fatigue resistant structural frame. Three types of welded continuous tubing frame intersections currently observed in the designs of agricultural equipment were compared to two non-continuous frame intersection designs. Each design was subjected to the same loading condition and then examined for stress levels using the Finite Element Method to predict fatigue life. Results demonstrated that a lighter weight, non-continuous member frame intersection design was two magnitudes superior in fatigue resistance than some current implemented frame designs when using Stress-Life fatigue prediction methods and empirical fatigue strengths for fillet welds. Stress-Life predictions were also made using theoretical fatigue strength calculations for the fatigue strength at the welds for comparison to the empirical derived weld fatigue strength
Boyer, Frederic; Porez, Mathieu; Renda, Federico
This talk presents recent geometric tools developed to model the locomotion dynamics of bio-inspired robots. Starting from the model of discrete rigid multibody systems we will rapidly shift to the case of continuous systems inspired from snakes and fish. To that end, we will build on the model of Cosserat media. This extended picture of geometric locomotion dynamics (inspired from fields' theory) will allow us to introduce models of swimming recently used in biorobotics. We will show how modeling a fish as a one-dimensional Cosserat medium allows to recover and extend the Large Amplitude Elongated Body theory of J. Lighthill and to apply it to an eel-like robot. In the same vein, modeling the mantle of cephalopods as a two dimensional Cosserat medium will build a basis for studying the jet propelling of a soft octopus like robot.
An Analysis of Frame Semantics of Continuous Processes
2016-08-10
continuous processes. Prior research mapped qualitative process elements onto English language constructions, but did not connect the...qualitative process (QP) theory provides a formal language for representing mental models of continuous systems. QP theory is domain general and... Information from Natural Language Texts. Proceedings of AAAI-2014 Ovchinnikova, E., Vieu, L., Oltramari, A., Borgo, S., & Alexandrov, T. (2010). Data
Energy Technology Data Exchange (ETDEWEB)
Guerra Romero, I.; Fernandez Majo, M. C.; Valdes, A. J.
2010-07-01
In this paper many bibliographic references have been analyses which deal on the importance of the buckling in rigid frames, and many versions of it, have been got. About 70 frames have been analysed by the authors and they have found that it is advisable to consider the bucking in the design of frames beams. (Author) 30 refs.
Lajimi, Seyed Amir Mousavi
2014-01-01
The nonlinear dynamics of a microbeam-rigid body gyroscope are investigated by using a continuation method. To study the nonlinear dynamics of the system, the Lagrangian of the system is discretized and the reduced-order model is obtained. By using the continuation method, the frequency-response curves are computed and the stability of response is determined.
Continuous shearlet frames and resolution of the wavefront set
Grohs, Philipp
2010-12-04
In recent years directional multiscale transformations like the curvelet- or shearlet transformation have gained considerable attention. The reason for this is that these transforms are-unlike more traditional transforms like wavelets-able to efficiently handle data with features along edges. The main result in Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009) confirming this property for shearlets is due to Kutyniok and Labate where it is shown that for very special functions ψ with frequency support in a compact conical wegde the decay rate of the shearlet coefficients of a tempered distribution f with respect to the shearlet ψ can resolve the wavefront set of f. We demonstrate that the same result can be verified under much weaker assumptions on ψ, namely to possess sufficiently many anisotropic vanishing moments. We also show how to build frames for L2(ℝ2)from any such function. To prove our statements we develop a new approach based on an adaption of the Radon transform to the shearlet structure. © 2010 Springer-Verlag.
Dobbs, Thomas D; Wall, Steven A; Richards, Peter G; Johnson, David
2014-10-01
Distraction osteogenesis (DO) has revolutionised the treatment of mid-face hypoplasia in children, allowing advancement of the mid-face in excess of that achievable by traditional Le Fort III osteotomy. One method of performing DO is to use an externally applied frame, such as the Rigid External Distraction (RED) frame. However, at young ages the cranial bone is often too weak to support the frame, preventing its safe use. We present the case of a patient with Crouzon syndrome who required mid-face distraction at 4-months of age due to severe exorbitism, raised intracranial pressure and airway compromise. In order to allow safe application of an external distraction frame laminated bone grafts were secured to the cranium at the areas of frame pin insertion. We believe this to be the first reported case of the use of the patients own cranial bone to create laminated bone grafts and thicken the site of pin insertion. The method described adds to the armamentarium of the surgeon treating these patients who require placement of an external distraction frame for DO at a young age where the thickness of the cranial bone may otherwise prevent safe application. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Antoine, Jean-Pierre [Institut de Recherche en Mathematique et Physique, Universite Catholique de Louvain, B-1348 Louvain-la Neuve (Belgium); Balazs, Peter, E-mail: jean-pierre.antoine@uclouvain.be, E-mail: peter.balazs@oeaw.ac.at [Acoustics Research Institute, Austrian Academy of Sciences, Wohllebengasse 12-14, A-1040 Vienna (Austria)
2011-05-20
Loosely speaking, a semi-frame is a generalized frame for which one of the frame bounds is absent. More precisely, given a total sequence in a Hilbert space, we speak of an upper (resp. lower) semi-frame if only the upper (resp. lower) frame bound is valid. Equivalently, for an upper semi-frame, the frame operator is bounded, but has an unbounded inverse, whereas a lower semi-frame has an unbounded frame operator, with a bounded inverse. We study mostly upper semi-frames, both in the continuous and discrete case, and give some remarks for the dual situation. In particular, we show that reconstruction is still possible in certain cases.
Energy Technology Data Exchange (ETDEWEB)
Nakai, H. (Osaka City University, Osaka (Japan). Faculty of Engineering); Miki, T. (Daido Institute of Technology, Nagoya (Japan)); Hashimoto, Y. (Hanshin Expressway Public Corp., Osaka (Japan))
1992-10-15
A remarkable shear lag phenomenon develops in flange plates in beam and column members at corner parts of steel rigid frames. A design method considering the shear lag phenomenon was proposed on rigid frame corner parts to which the beam and column members with box-like cross section are connected perpendicularly. Firstly, mechanisms to transfer forces in the corner parts having been discussed previously and their experimental results were considered, so that the distribution characteristics of sectional forces working on the beam and column members at the corner parts and their vicinities can be explained with help of a simple beam theory. Secondly, a shear lag analysis was carried out on a model to show solutions of added bending moment corresponding to vertical stress. A simple and practicable calculation formula was yielded for a maximum added bending moment at the connecting points of the beam and column members to present a method to check stresses at the corner parts in a limit state. A proposition was made on an ultimate strength checking method based on the yields of flange plates in the beam and column members on webs at the corner parts or their vicinity. 15 refs., 15 figs.
Czech Academy of Sciences Publication Activity Database
Dudová, Radka
2010-01-01
Roč. 46, č. 6 (2010), s. 945-975 ISSN 0038-0288 Institutional research plan: CEZ:AV0Z70280505 Keywords : abortion policy * body discourse * frame analysis Subject RIV: AO - Sociology, Demography Impact factor: 0.389, year: 2010
Mashayekh, Adel
2017-01-01
Steel Special Moment Frames (SMF) are one of the most popular lateral force-resisting systems for multistory building construction in high seismic regions due to their architectural versatility. With a significant amount of research that was conducted after the 1994 Northridge, California earthquake, AISC has published design guidelines (AISC 341 and AISC 358) to avoid brittle fracture of beam-to-column welded moment connections that occurred in more than 100 steel buildings. This dissertat...
Directory of Open Access Journals (Sweden)
Wildemeersch D
2015-07-01
with conventional (framed IUDs were between 33.8% and 80% at 1 year for studies providing 1 year rates and between 68% and 94.1% for studies reporting continuation rates at 6 months. Studies utilizing frameless IUDs reported 1 year continuation rate over 95%. Conclusion: Frameless IUDs, due to their attachment to the uterine fundus, appear to be better retained by the postabortal uterus when compared with conventional framed IUDs. The absence of a frame ensures compatibility with uterine cavity anatomical dimensions, and may therefore result in improved acceptability and continuation rates in comparison with framed IUDs. Both these characteristics of the frameless IUD could help reduce the number of repeat unwanted pregnancies and subsequent abortions in some cases. Keywords: IUD, abortion, frameless IUD, expulsion, continuation, repeat abortion, unintended pregnancy
Irschik, H.; Krommer, M.; Nader, M.; Vetyukov, Y.; von Garssen, H.-G.
2015-01-01
The present paper is concerned with Lagrange's Equations, applied to a deformable body in the presence of rigid body degrees of freedom. The Lagrange description of Continuum Mechanics is used. An exact version of the Equations is derived first. This version, which represents an identical extension of the Fundamental Law of Dynamics, does involve the idea of virtual motions. The virtual motion is described in the framework of the Ritz-Ansatz, but our derivation does not make use of D'Alemberts principle, the principle of virtual work, or variational principles. From the exact version, by involving arguments related to the Galerkin approximation technique, we derive an approximate Ritz type version of Lagrange's Equations. This approximate version coincides with the traditional one, which is based on the notion of kinetic energy. However, since our derivation stems from the Fundamental Law of Dynamics, we have at our disposal an alternative formulation, which is based on the notion of local momentum. This momentum based version, which is the main topic of the present contribution, can be used for the purpose of performing independent checks of the energy based version of Lagrange's Equations. The momentum based version also clarifies that and how certain terms in the energy based version do cancel out. The momentum based version is worked out in the framework of the Floating Frame of Reference Formulation of Multibody Dynamics. Explicit formulas for the single terms of Lagrange's Equations are derived for the translational, rotational and flexible degrees of freedom of the deformable body, respectively. Corresponding Lagrange's Equations are explained in the light of the relations of Balance of Total Momentum, Balance of Total Moment of Momentum, of the Mean Stress Theorem and the notion of Virial of Forces. An embedding into the literature is given.
Discretization of continuous frame
Indian Academy of Sciences (India)
Author Affiliations. A Fattahi1 H Javanshiri2. Department of Mathematics, Razi University, Kermanshah, Iran; Department of Mathematical Sciences, Isfahan University of Technology, Isfahan 84156-83111, Iran ...
Ippolito, Corey; Nguyen, Nhan; Totah, Joe; Trinh, Khanh; Ting, Eric
2013-01-01
In this paper, we describe an initial optimization study of a Variable-Camber Continuous Trailing-Edge Flap (VCCTEF) system. The VCCTEF provides a light-weight control system for aircraft with long flexible wings, providing efficient high-lift capability for takeoff and landing, and greater efficiency with reduced drag at cruising flight by considering the effects of aeroelastic wing deformations in the control law. The VCCTEF system is comprised of a large number of distributed and individually-actuatable control surfaces that are constrained in movement relative to neighboring surfaces, and are non-trivially coupled through structural aeroelastic dynamics. Minimzation of drag results in a constrained, coupled, non-linear optimization over a high-dimension search space. In this paper, we describe the modeling, analysis, and optimization of the VCCTEF system control inputs for minimum drag in cruise. The purpose of this initial study is to quantify the expected benefits of the system concept. The scope of this analysis is limited to consideration of a rigid wing without structural flexibility in a steady-state cruise condition at various fuel weights. For analysis, we developed an optimization engine that couples geometric synthesis with vortex-lattice analysis to automate the optimization procedure. In this paper, we present and describe the VCCTEF system concept, optimization approach and tools, run-time performance, and results of the optimization at 20%, 50%, and 80% fuel load. This initial limited-scope study finds the VCCTEF system can potentially gain nearly 10% reduction in cruise drag, provides greater drag savings at lower operating weight, and efficiency is negatively impacted by the severity of relative constraints between control surfaces.
Learned Non-Rigid Object Motion is a View-Invariant Cue to Recognizing Novel Objects.
Chuang, Lewis L; Vuong, Quoc C; Bülthoff, Heinrich H
2012-01-01
There is evidence that observers use learned object motion to recognize objects. For instance, studies have shown that reversing the learned direction in which a rigid object rotated in depth impaired recognition accuracy. This motion reversal can be achieved by playing animation sequences of moving objects in reverse frame order. In the current study, we used this sequence-reversal manipulation to investigate whether observers encode the motion of dynamic objects in visual memory, and whether such dynamic representations are encoded in a way that is dependent on the viewing conditions. Participants first learned dynamic novel objects, presented as animation sequences. Following learning, they were then tested on their ability to recognize these learned objects when their animation sequence was shown in the same sequence order as during learning or in the reverse sequence order. In Experiment 1, we found that non-rigid motion contributed to recognition performance; that is, sequence-reversal decreased sensitivity across different tasks. In subsequent experiments, we tested the recognition of non-rigidly deforming (Experiment 2) and rigidly rotating (Experiment 3) objects across novel viewpoints. Recognition performance was affected by viewpoint changes for both experiments. Learned non-rigid motion continued to contribute to recognition performance and this benefit was the same across all viewpoint changes. By comparison, learned rigid motion did not contribute to recognition performance. These results suggest that non-rigid motion provides a source of information for recognizing dynamic objects, which is not affected by changes to viewpoint.
Rotating and rolling rigid bodies and the "hairy ball" theorem
Bormashenko, Edward; Kazachkov, Alexander
2017-06-01
Rotating and rolling rigid bodies exemplify a fascinating theorem of topology, jokingly called the "hairy ball" theorem, which demands that any continuous tangent vector field on the sphere has at least one point where the field is zero. We demonstrate via a gedanken experiment how drilling through a rotating ball, thereby converting it into a torus, leads to the elimination of zero-velocity points on the ball surface. Using the same reasoning, zero-velocity points can be removed from the surface of a drilled spinning top. We discuss the location of zero-velocity points on the surfaces of rigid bodies rolling with no slip and with slip. Observations made from different reference frames identify various zero-velocity points. Illustrative experiments visualizing zero-velocity points are presented.
Directory of Open Access Journals (Sweden)
Todd McElroy
2007-08-01
Full Text Available We examined how the goal of a decision task influences the perceived positive, negative valence of the alternatives and thereby the likelihood and direction of framing effects. In Study 1 we manipulated the goal to increase, decrease or maintain the commodity in question and found that when the goal of the task was to increase the commodity, a framing effect consistent with those typically observed in the literature was found. When the goal was to decrease, a framing effect opposite to the typical findings was observed whereas when the goal was to maintain, no framing effect was found. When we examined the decisions of the entire population, we did not observe a framing effect. In Study 2, we provided participants with a similar decision task except in this situation the goal was ambiguous, allowing us to observe participants' self-imposed goals and how they influenced choice preferences. The findings from Study 2 demonstrated individual variability in imposed goal and provided a conceptual replication of Study 1. %need keywords
Antoine, Jean-Pierre; Balazs, Peter
2011-01-01
Loosely speaking, a semi-frame is a generalized frame for which one of the frame bounds is absent. More precisely, given a total sequence in a Hilbert space, we speak of an upper (resp. lower) semi-frame if only the upper (resp. lower) frame bound is valid. Equivalently, for an upper semi-frame, the frame operator is bounded, but has an unbounded inverse, whereas a lower semi-frame has an unbounded frame operator, with bounded inverse. We study mostly upper semi-frames, bot...
QUADCOPTER BODY FRAME MODEL AND ANALYSIS
KUANTAMA Endrowednes; CRACIUN Dan; TARCA Radu
2016-01-01
Quadcopter frame modeling is useful to analyze the reliability of body frame part and to help determine the type of rotor and propeller in order to assure the necessary flight acceleration. Quadcopter flight stability is influenced by the resulting thrust, by the distance between each rotor propeller and also by the frame rigidity; the frame has been designed to be as light as possible, meanwhile maintaining the strength to carry the load. Solidworks software has been used to design and analy...
DEFF Research Database (Denmark)
Pedersen, Rasmus T.
2017-01-01
The concept of media framing refers to the way in which the news media organize and provide meaning to a news story by emphasizing some parts of reality and disregarding other parts. These patterns of emphasis and exclusion in news coverage create frames that can have considerable effects on news...... consumers’ perceptions and attitudes regarding the given issue or event. This entry briefly elaborates on the concept of media framing, presents key types of media frames, and introduces the research on media framing effects....
Lonergan, K M; Gray, M W
1996-04-19
We have investigated the expression of a continuous open reading frame (ORF) present in the mitochondrial genome of Acanthamoeba castellanii and specifying the two largest subunits (COX1 and COX2) of the cytochrome c oxidase complex. Northern hybridization and primer extension analysis demonstrated that this ORF (cox1/2, 873 codons) is transcribed as part of a 4.7 kb RNA that also includes the upstream small subunit rRNA sequence. Between the cox1 and cox2 portions of the transcript, RNA sequence exactly matches gene sequence, excluding the possibility that a standard cox1 termination codon is created by post-transcriptional RNA processing or editing. Western analysis revealed an A. castellanii COX2 protein with a mobility matching that of mature COX2 from yeast (Saccharomyces cerevisiae) mitochondria. These observations indicate that although A. castellanii COX1 and COX2 are apparently translated from the same ORF, they do not exist in mature form as a COX1-COX2 "fusion" protein. Whereas translation of COX2 could potentially be initiated from an internal AUG codon in the cox1/2 ORF, COX1 must be generated either through an unusual translation termination mechanism acting between the cox1 and cox2 coding regions of the cox1/2 mRNA, or by co-translational or post-translational proteolytic processing of a translation product whose synthesis continues into the cox2 coding region. Because the cox2 nucleotide sequence predicts a COX2 protein considerably larger than that observed by Western analysis, A. castellanii COX2 may undergo additional post-translational processing to its final form.
Lecheler, S.K.
2010-01-01
This dissertation supplies a number of research findings that add to a theory of news framing effects, and also to the understanding of the role media effects play in political communication. We show that researchers must think more about what actually constitutes a framing effect, and that a
DEFF Research Database (Denmark)
Peder Pedersen, Claus
2018-01-01
On framing as artistic and conceptual tool in the works of Claudia Carbone. Contribution to exhibition at the Aarhus School of Architecture.......On framing as artistic and conceptual tool in the works of Claudia Carbone. Contribution to exhibition at the Aarhus School of Architecture....
Weiss, Asia; Whiteley, Walter
2014-01-01
This book contains recent contributions to the fields of rigidity and symmetry with two primary focuses: to present the mathematically rigorous treatment of rigidity of structures, and to explore the interaction of geometry, algebra, and combinatorics. Overall, the book shows how researchers from diverse backgrounds explore connections among the various discrete structures with symmetry as the unifying theme. Contributions present recent trends and advances in discrete geometry, particularly in the theory of polytopes. The rapid development of abstract polytope theory has resulted in a rich theory featuring an attractive interplay of methods and tools from discrete geometry, group theory, classical geometry, hyperbolic geometry and topology. The volume will also be a valuable source as an introduction to the ideas of both combinatorial and geometric rigidity theory and its applications, incorporating the surprising impact of symmetry. It will appeal to students at both the advanced undergraduate and gradu...
Directory of Open Access Journals (Sweden)
Hyunsun Catherine Yoon
2017-08-01
Full Text Available This paper examines the way in which news about Gangnam Style was framed in the Korean press. First released on 15th July 2012, it became the first video to pass two billion views on YouTube. 400 news articles between July 2012 and March 2013 from two South Korean newspapers - Chosun Ilbo and Hankyoreh were analyzed using the frame analysis method in five categories: industry/economy, globalization, cultural interest, criticism, and competition. The right-left opinion cleavage is important because news frames interact with official discourses, audience frames and prior knowledge which consequently mediate effects on public opinion, policy debates, social movement and individual interpretations. Whilst the existing literature on Gangnam Style took rather holistic approach, this study aimed to fill the lacuna, considering this phenomenon as a dynamic process, by segmenting different stages - recognition, spread, peak and continuation. Both newspapers acknowledged Gangnam Style was an epochal event but their perspectives and news frames were different; globalization frame was most frequently used in Chosun Ilbo whereas cultural interest frame was most often used in Hankyoreh. Although more critical approaches were found in Hankyoreh, reflecting the right-left opinion cleavage, both papers lacked in critical appraisal and analysis of Gangnam Style’s reception in a broader context of the new Korean Wave.
Energy Technology Data Exchange (ETDEWEB)
Meson, Alejandro M., E-mail: meson@iflysib.unlp.edu.ar; Vericat, Fernando, E-mail: vericat@iflysib.unlp.edu.ar [CONICET-UNLP, Instituto de Fisica de Liquidos y Sistemas Biologicos (IFLYSIB) (Argentina)
2011-12-15
We analyze when a multifractal spectrum can be used to recover the potential. This phenomenon is known as multifractal rigidity. We prove that for a certain class of potentials the multifractal spectrum of local entropies uniquely determines their equilibrium states. This leads to a classification which identifies two systems up to a change of variables.
Czech Academy of Sciences Publication Activity Database
Svoboda, Jan; Telenský, Petr; Blahna, Karel; Vodička, Martin; Stuchlík, Aleš
2015-01-01
Roč. 292, Oct 1 (2015), s. 1-9 ISSN 0166-4328 R&D Projects: GA ČR(CZ) GA14-03627S Institutional support: RVO:67985823 Keywords : posterior parietal cortex * reference frame * navigation * lesion * rat Subject RIV: FH - Neurology Impact factor: 3.002, year: 2015
DEFF Research Database (Denmark)
Bundgaard, Charlotte
2009-01-01
to create architectural meaning and give character to an architecture of fragmentation. Layers are both seen as conceptual as well as material frames which define certain strong properties or meanings in the architectural work. Defining layers is a way of separating and organizing; it both defines...
Rigid supersymmetry with boundaries
Energy Technology Data Exchange (ETDEWEB)
Belyaev, D.V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Van Nieuwenhuizen, P. [State Univ. of New York, Stony Brook, NY (United States). C.N. Yang Inst. for Theoretical Physics
2008-01-15
We construct rigidly supersymmetric bulk-plus-boundary actions, both in x-space and in superspace. For each standard supersymmetric bulk action a minimal supersymmetric bulk-plus-boundary action follows from an extended F- or D-term formula. Additional separately supersymmetric boundary actions can be systematically constructed using co-dimension one multiplets (boundary superfields). We also discuss the orbit of boundary conditions which follow from the Euler-Lagrange variational principle. (orig.)
Rigid supersymmetry with boundaries
International Nuclear Information System (INIS)
Belyaev, D.V.; Van Nieuwenhuizen, P.
2008-01-01
We construct rigidly supersymmetric bulk-plus-boundary actions, both in x-space and in superspace. For each standard supersymmetric bulk action a minimal supersymmetric bulk-plus-boundary action follows from an extended F- or D-term formula. Additional separately supersymmetric boundary actions can be systematically constructed using co-dimension one multiplets (boundary superfields). We also discuss the orbit of boundary conditions which follow from the Euler-Lagrange variational principle. (orig.)
De Leersnyder, Fien; Peeters, Elisabeth; Djalabi, Hasna; Vanhoorne, Valérie; Van Snick, Bernd; Hong, Ke; Hammond, Stephen; Liu, Angela Yang; Ziemons, Eric; Vervaet, Chris; De Beer, Thomas
2018-03-20
A calibration model for in-line API quantification based on near infrared (NIR) spectra collection during tableting in the tablet press feed frame was developed and validated. First, the measurement set-up was optimised and the effect of filling degree of the feed frame on the NIR spectra was investigated. Secondly, a predictive API quantification model was developed and validated by calculating the accuracy profile based on the analysis results of validation experiments. Furthermore, based on the data of the accuracy profile, the measurement uncertainty was determined. Finally, the robustness of the API quantification model was evaluated. An NIR probe (SentroPAT FO) was implemented into the feed frame of a rotary tablet press (Modul™ P) to monitor physical mixtures of a model API (sodium saccharine) and excipients with two different API target concentrations: 5 and 20% (w/w). Cutting notches into the paddle wheel fingers did avoid disturbances of the NIR signal caused by the rotating paddle wheel fingers and hence allowed better and more complete feed frame monitoring. The effect of the design of the notched paddle wheel fingers was also investigated and elucidated that straight paddle wheel fingers did cause less variation in NIR signal compared to curved paddle wheel fingers. The filling degree of the feed frame was reflected in the raw NIR spectra. Several different calibration models for the prediction of the API content were developed, based on the use of single spectra or averaged spectra, and using partial least squares (PLS) regression or ratio models. These predictive models were then evaluated and validated by processing physical mixtures with different API concentrations not used in the calibration models (validation set). The β-expectation tolerance intervals were calculated for each model and for each of the validated API concentration levels (β was set at 95%). PLS models showed the best predictive performance. For each examined saccharine
Mendes, Kaitlynn
2011-01-01
This article analyses the framing in four British and American newspapers of the second wave feminist movement during its most politically active period (1968–1982). Using content and critical discourse analysis of 555 news articles, the article investigates how movement members were represented, what problems and solutions to women’s oppression/inequality were posed and whose voices were used. This paper identifies: opposition to the movement, support for the movement, conflict and movement ...
Park, Sora; Kittimanapun, Kritsada; Ahn, Jeung Sun; Kwon, Young-Kyun; Tománek, David
2010-08-25
We use ab initio density functional calculations to study the stability, elastic properties and electronic structure of sp(2) carbon minimal surfaces with negative Gaussian curvature, called schwarzites. We focus on two systems with cubic unit cells containing 152 and 200 carbon atoms, which are metallic and very rigid. The porous schwarzite structure allows for efficient and reversible doping by electron donors and acceptors, making it a promising candidate for the next generation of alkali ion batteries. We identify schwarzite structures that act as arrays of interconnected spin quantum dots or become magnetic when doped. We introduce two interpenetrating schwarzite structures that may find their use as the ultimate super-capacitor.
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
Maintaining a good image and reputation in the eyes of stakeholders is vital to the organisation. Thus, in its corporate communication and discourse the organisation will seek to present or frame itself as favourably as possible while observing regulations stipulating accuracy and precision...... in the information given. However, in this process the organisation is not operating in a social vacuum but is continuously interacting with various players, such as the media, for its textual and discursive creation (Gunnarsson 2009). In this presentation, I will focus on the role of this interaction in framing...... an organisation, and hence in shaping the image projected to the public. Framing is here understood as the selection of ‘some aspects of perceived reality … [making] them more salient in the communication text, in such a way as to promote a particular problem definition, causal interpretation, moral evaluation...
Torsional Rigidity of Minimal Submanifolds
DEFF Research Database (Denmark)
Markvorsen, Steen; Palmer, Vicente
2006-01-01
We prove explicit upper bounds for the torsional rigidity of extrinsic domains of minimal submanifolds $P^m$ in ambient Riemannian manifolds $N^n$ with a pole $p$. The upper bounds are given in terms of the torsional rigidities of corresponding Schwarz symmetrizations of the domains in warped...
Quantum charged rigid membrane
International Nuclear Information System (INIS)
Cordero, Ruben; Molgado, Alberto; Rojas, Efrain
2011-01-01
The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach, we observed that the theory comprises the management of both first- and second-class constraints. We thus show that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits us to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.
Quantum charged rigid membrane
Energy Technology Data Exchange (ETDEWEB)
Cordero, Ruben [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N., Unidad Adolfo Lopez Mateos, Edificio 9, 07738 Mexico, D.F. (Mexico); Molgado, Alberto [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Zacatecas Zac. (Mexico); Rojas, Efrain, E-mail: cordero@esfm.ipn.mx, E-mail: amolgado@fisica.uaz.edu.mx, E-mail: efrojas@uv.mx [Departamento de Fisica, Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)
2011-03-21
The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach, we observed that the theory comprises the management of both first- and second-class constraints. We thus show that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits us to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.
Directory of Open Access Journals (Sweden)
Gabriela Águila
2013-04-01
Full Text Available The article analyzes an intelligence agency acting provincial level (province of Santa Fe, which was not part of the police or military orbit and worked steadily between 1966 and the early 90s. It discusses its objectives and functions, rules, structure and agents, their actions and practices, recording the continuities and changes experienced over its decades of existence. It aims to contribute to a study of a particular case the knowledge of one of the gray areas, perhaps the most opaque, the exercise of repression in Argentina: the performance of the intelligence services.
Reference Prices and Nominal Rigidities
Eichenbaum, Martin; Jaimovich, Nir; Rebelo, Sérgio
2008-01-01
We assess the importance of nominal rigidities using a new weekly scanner data set from a major U.S. retailer, that contains information on prices, quantities, and costs for over 1,000 stores. We find that nominal rigidities are important but do not take the form of sticky prices. Instead, nominal rigidities take the form of inertia in reference prices and costs, defined as the most common prices and costs within a given quarter. Weekly prices and costs fluctuate around reference values which...
DEFF Research Database (Denmark)
Rijkhoff, Jan
2008-01-01
, Non-Verb, Modifier), there are also flexible word classes within the rigid lexical category Noun (Set Noun, Sort Noun, General Noun). Members of flexible word classes are characterized by their vague semantics, which in the case of nouns means that values for the semantic features Shape...... and Homogeneity are either left undetermined or they are specified in such a way that they do not quite match the properties of the kind of entity denoted by the flexible item in the external world. I will then argue that flexible word classes constitute a proper category (i.e. they are not the result of a merger...... of some rigid word classes) in that members of flexible word categories display the same properties regarding category membership as members of rigid word classes. Finally this article wants to claim that the distinction between rigid and flexible noun categories (a) adds a new dimension to current...
Nonmonotonic belief state frames and reasoning frames
Engelfriet, J.; Herre, H.; Treur, J.
1995-01-01
In this paper five levels of specification of nonmonotonic reasoning are distinguished. The notions of semantical frame, belief state frame and reasoning frame are introduced and used as a semantical basis for the first three levels. Moreover, the semantical connections between the levels are
Selection pressure in alternative reading frames.
Directory of Open Access Journals (Sweden)
Katharina Mir
Full Text Available Overlapping genes are two protein-coding sequences sharing a significant part of the same DNA locus in different reading frames. Although in recent times an increasing number of examples have been found in bacteria the underlying mechanisms of their evolution are unknown. In this work we explore how selective pressure in a protein-coding sequence influences its overlapping genes in alternative reading frames. We model evolution using a time-continuous Markov process and derive the corresponding model for the remaining frames to quantify selection pressure and genetic noise. Our findings lead to the presumption that, once information is embedded in the reverse reading frame -2 (relative to the mother gene in +1 purifying selection in the protein-coding reading frame automatically protects the sequences in both frames. We also found that this coincides with the fact that the genetic noise measured using the conditional entropy is minimal in frame -2 under selection in the coding frame.
Understanding geological processes: Visualization of rigid and non-rigid transformations
Shipley, T. F.; Atit, K.; Manduca, C. A.; Ormand, C. J.; Resnick, I.; Tikoff, B.
2012-12-01
Visualizations are used in the geological sciences to support reasoning about structures and events. Research in cognitive sciences offers insights into the range of skills of different users, and ultimately how visualizations might support different users. To understand the range of skills needed to reason about earth processes we have developed a program of research that is grounded in the geosciences' careful description of the spatial and spatiotemporal patterns associated with earth processes. In particular, we are pursuing a research program that identifies specific spatial skills and investigates whether and how they are related to each other. For this study, we focus on a specific question: Is there an important distinction in the geosciences between rigid and non-rigid deformation? To study a general spatial thinking skill we employed displays with non-geological objects that had been altered by rigid change (rotation), and two types of non-rigid change ("brittle" (or discontinuous) and "ductile" (or continuous) deformation). Disciplinary scientists (geosciences and chemistry faculty), and novices (non-science faculty and undergraduate psychology students) answered questions that required them to visualize the appearance of the object before the change. In one study, geologists and chemists were found to be superior to non-science faculty in reasoning about rigid rotations (e.g., what an object would look like from a different perspective). Geologists were superior to chemists in reasoning about brittle deformations (e.g., what an object looked like before it was broken - here the object was a word cut into many fragments displaced in different directions). This finding is consistent with two hypotheses: 1) Experts are good at visualizing the types of changes required for their domain; and 2) Visualization of rigid and non-rigid changes are not the same skill. An additional important finding is that there was a broad range of skill in both rigid and non-rigid
The role of rigidity in controlling material failure.
Driscoll, Michelle M; Chen, Bryan Gin-Ge; Beuman, Thomas H; Ulrich, Stephan; Nagel, Sidney R; Vitelli, Vincenzo
2016-09-27
We investigate how material rigidity acts as a key control parameter for the failure of solids under stress. In both experiments and simulations, we demonstrate that material failure can be continuously tuned by varying the underlying rigidity of the material while holding the amount of disorder constant. As the rigidity transition is approached, failure due to the application of uniaxial stress evolves from brittle cracking to system-spanning diffuse breaking. This evolution in failure behavior can be parameterized by the width of the crack. As a system becomes more and more floppy, this crack width increases until it saturates at the system size. Thus, the spatial extent of the failure zone can be used as a direct probe for material rigidity.
About ideal relative motions of rigid heavy body
Directory of Open Access Journals (Sweden)
Nicolae MARCOV
2017-06-01
Full Text Available Consider an origin which is fixed at the Earth’s surface, and a rectangular celestial coordinates axes with this origin. The gravity acceleration is the approximate sum of the centrifugal acceleration of the origin relatively to the Earth’s center and the Newton’s gravitational acceleration due to the Earth’s attraction. Thus the selected reference frame is formally an inertial frame. The origin is also a point of a rigid heavy body. The dynamical differential system of absolute motion of the three degrees-of- freedom body is given. Some notable solutions of this system are calculated relatively to a moving laboratory frame with the angular velocity of the Earth.
Rigidly foldable origami gadgets and tessellations.
Evans, Thomas A; Lang, Robert J; Magleby, Spencer P; Howell, Larry L
2015-09-01
Rigidly foldable origami allows for motion where all deflection occurs at the crease lines and facilitates the application of origami in materials other than paper. In this paper, we use a recently discovered method for determining rigid foldability to identify existing flat-foldable rigidly foldable tessellations, which are also categorized. We introduce rigidly foldable origami gadgets which may be used to modify existing tessellations or to create new tessellations. Several modified and new rigidly foldable tessellations are presented.
Rigidity-tuning conductive elastomer
Shan, Wanliang; Diller, Stuart; Tutcuoglu, Abbas; Majidi, Carmel
2015-06-01
We introduce a conductive propylene-based elastomer (cPBE) that rapidly and reversibly changes its mechanical rigidity when powered with electrical current. The elastomer is rigid in its natural state, with an elastic (Young’s) modulus of 175.5 MPa, and softens when electrically activated. By embedding the cPBE in an electrically insulating sheet of polydimethylsiloxane (PDMS), we create a cPBE-PDMS composite that can reversibly change its tensile modulus between 37 and 1.5 MPa. The rigidity change takes ˜6 s and is initiated when a 100 V voltage drop is applied across the two ends of the cPBE film. This magnitude of change in elastic rigidity is similar to that observed in natural skeletal muscle and catch connective tissue. We characterize the tunable load-bearing capability of the cPBE-PDMS composite with a motorized tensile test and deadweight experiment. Lastly, we demonstrate the ability to control the routing of internal forces by embedding several cPBE-PDMS ‘active tendons’ into a soft robotic pneumatic bending actuator. Selectively activating the artificial tendons controls the neutral axis and direction of bending during inflation.
Rigidity-tuning conductive elastomer
International Nuclear Information System (INIS)
Shan, Wanliang; Diller, Stuart; Tutcuoglu, Abbas; Majidi, Carmel
2015-01-01
We introduce a conductive propylene-based elastomer (cPBE) that rapidly and reversibly changes its mechanical rigidity when powered with electrical current. The elastomer is rigid in its natural state, with an elastic (Young’s) modulus of 175.5 MPa, and softens when electrically activated. By embedding the cPBE in an electrically insulating sheet of polydimethylsiloxane (PDMS), we create a cPBE–PDMS composite that can reversibly change its tensile modulus between 37 and 1.5 MPa. The rigidity change takes ∼6 s and is initiated when a 100 V voltage drop is applied across the two ends of the cPBE film. This magnitude of change in elastic rigidity is similar to that observed in natural skeletal muscle and catch connective tissue. We characterize the tunable load-bearing capability of the cPBE–PDMS composite with a motorized tensile test and deadweight experiment. Lastly, we demonstrate the ability to control the routing of internal forces by embedding several cPBE–PDMS ‘active tendons’ into a soft robotic pneumatic bending actuator. Selectively activating the artificial tendons controls the neutral axis and direction of bending during inflation. (paper)
Seismic behavior and design of wall-EDD-frame systems
Directory of Open Access Journals (Sweden)
Oren eLavan
2015-06-01
Full Text Available Walls and frames have different deflection lines and, depending on the seismic mass they support, may often poses different natural periods. In many cases, wall-frame structures present an advantageous behavior. In these structures the walls and the frames are rigidly connected. Nevertheless, if the walls and the frames were not rigidly connected, an opportunity for an efficient passive control strategy would arise: Connecting the two systems by energy dissipation devices (EDDs to result in wall-EDD-frame systems. This, depending on the parameters of the system, is expected to lead to an efficient energy dissipation mechanism.This paper studies the seismic behavior of wall-EDD-frame systems in the context of retrofitting existing frame structures. The controlling non-dimensional parameters of such systems are first identified. This is followed by a rigorous and extensive parametric study that reveals the pros and cons of the new system versus wall-frame systems. The effect of the controlling parameters on the behavior of the new system are analyzed and discussed. Finally, tools are given for initial design of such retrofitting schemes. These enable both choosing the most appropriate retrofitting alternative and selecting initial values for its parameters.
Rigid and Elastic Sub-Base Effects on Tall Steel | Oyetola | Nigerian ...
African Journals Online (AJOL)
The whole frame-system are designed resting on rigid strip support (k=¥) and on elastic sub-base (k=1500T/m3). The vertical loads (dead and imposed) and the horizontal loads were treated separately for the frames. One of the oldest models of elastic sub-base proposed by E. Winkler (1867) was employed. It is believed ...
Rigid body dynamics of mechanisms
Hahn, Hubert
2003-01-01
The second volume of Rigid Body Dynamics of Mechanisms covers applications via a systematic method for deriving model equations of planar and spatial mechanisms. The necessary theoretical foundations have been laid in the first volume that introduces the theoretical mechanical aspects of mechatronic systems. Here the focus is on the application of the modeling methodology to various examples of rigid-body mechanisms, simple planar ones as well as more challenging spatial problems. A rich variety of joint models, active constraints, plus active and passive force elements is treated. The book is intended for self-study by working engineers and students concerned with the control of mechanical systems, i.e. robotics, mechatronics, vehicles, and machine tools. The examples included are a likely source from which to choose models for university lectures.
DEFF Research Database (Denmark)
Rijkhoff, Jan
2010-01-01
This article argues that in addition to the major flexible lexical categories in Hengeveld’s classification of parts of speech systems (Contentive, Non-Verb, Modifier), there are also flexible word classes within the rigid lexical category Noun (Set Noun, Sort Noun, General Noun). Members...... of flexible word classes are characterized by their vague semantics, which in the case of nouns means that values for the semantic features Shape and Homogeneity are either left undetermined or they are specified in such a way that they do not quite match the properties of the kind of entity denoted...... classes. Finally this article wants to claim that the distinction between rigid and flexible noun categories (a) adds a new dimension to current classifications of parts of speech systems, (b) correlates with certain grammatical phenomena (e.g. so-called number discord), and (c) helps to explain the parts...
Signature of Thermal Rigidity Percolation
International Nuclear Information System (INIS)
Huerta, Adrián
2013-01-01
To explore the role that temperature and percolation of rigidity play in determining the macroscopic properties, we propose a model that adds translational degrees of freedom to the spins of the well known Ising hamiltonian. In particular, the Ising model illustrate the longstanding idea that the growth of correlations on approach to a critical point could be describable in terms of the percolation of some sort of p hysical cluster . For certain parameters of this model we observe two well defined peaks of C V , that suggest the existence of two kinds of p hysical percolation , namely connectivity and rigidity percolation. Thermal fluctuations give rise to two different kinds of elementary excitations, i.e. droplets and configuron, as suggested by Angell in the framework of a bond lattice model approach. The later is reflected in the fluctuations of redundant constraints that gives stability to the structure and correlate with the order parameter
Making students' frames explicit
DEFF Research Database (Denmark)
Nielsen, Louise Møller; Hansen, Poul Henrik Kyvsgaard
2016-01-01
Framing is a vital part of the design and innovation process. Frames are cognitive shortcuts (i.e. metaphors) that enable designers to connect insights about i.e. market opportunities and users needs with a set of solution principles and to test if this connection makes sense. Until now, framing...
Decisions with endogenous frames
Dalton, P.S.; Ghosal, S.
2012-01-01
We develop a model of decision-making with endogenous frames and contrast the normative implications of our model to those of choice theoretic models in which observed choices are determined by exogenous frames or ancillary conditions. We argue that, frames, though they may be taken as given by the
Fusion frames and G-frames in Banach spaces
Indian Academy of Sciences (India)
Fusion frames and -frames in Hilbert spaces are generalizations of frames, and frames were extended to Banach spaces. In this article we introduce fusion frames, -frames, Banach -frames in Banach spaces and we show that they share many useful properties with their corresponding notions in Hilbert spaces. We also ...
Frame-to-frame coherent GPU splatting
Grau Carrion, Sergi; Tost Pardell, Daniela
2008-01-01
Recently, several improvements of the classical splatting volume rendering technique have been proposed, specifically, GPU implementations that considerably speed it up. However, splatting time-varying data, even using the GPU, is still slow and not very suitable for interactive data exploration through time. In this paper, we propose a GPU-based viewaligned splatting algorithm that exploits frame-to-frame coherence to render time-varying volume datasets. Our method run-length enc...
Strategies for economic design of unbraced steel frames
Steenhuis, C.M.; Weynand, K.; Gresnigt, A.M.
1998-01-01
In frame design for optimal economy, beam and column properties, as well as the properties of the joints, should be selected in such a way that economy can be achieved during fabrication. A method by which an impression of the possible layout of rigid joints can be obtained in a very early design
Directory of Open Access Journals (Sweden)
Piven Valeriy
2016-01-01
Full Text Available The reciprocal motions at the vibrational separating machines of the sieving trunks, transmitted from the actuating mechanism, vibrate frame. The Frame weaving is put over the sieving trunks weaving, disturbing the optimal mode of operation. Therefore, for the bearing structures of separating machines vibration decrease it is necessary to optimize its structures and characteristics of the actuating mechanism, which would provide the minimal mass with the necessarily frame rigidity.
Skopina, Maria; Protasov, Vladimir
2016-01-01
This book presents a systematic study of multivariate wavelet frames with matrix dilation, in particular, orthogonal and bi-orthogonal bases, which are a special case of frames. Further, it provides algorithmic methods for the construction of dual and tight wavelet frames with a desirable approximation order, namely compactly supported wavelet frames, which are commonly required by engineers. It particularly focuses on methods of constructing them. Wavelet bases and frames are actively used in numerous applications such as audio and graphic signal processing, compression and transmission of information. They are especially useful in image recovery from incomplete observed data due to the redundancy of frame systems. The construction of multivariate wavelet frames, especially bases, with desirable properties remains a challenging problem as although a general scheme of construction is well known, its practical implementation in the multidimensional setting is difficult. Another important feature of wavelet is ...
Dynamic Simulation of Rigid Guide Structure Based on ANSYS
Directory of Open Access Journals (Sweden)
Zhang Xin
2017-01-01
Full Text Available In order to reflect the varying law of the deflection of the rigid guide when the relative motion occur between the rigid guide and the cage roller, transient dynamic simulation is carried out for the commonly used calculation model of rigid guide and bunton by ANSYS. Simulation of the horizontal force through a section of the guide evenly, and the deflection curves of each model are obtained. It is found that the deflection of the simply supported beam model is the largest, and the three-span continuous beam model have similar peak spans in each span with the spatial grid model, but the spatial grid model has obvious fluctuation with the horizontal force.
Changing climate, changing frames
International Nuclear Information System (INIS)
Vink, Martinus J.; Boezeman, Daan; Dewulf, Art; Termeer, Catrien J.A.M.
2013-01-01
Highlights: ► We show development of flood policy frames in context of climate change attention. ► Rising attention on climate change influences traditional flood policy framing. ► The new framing employs global-scale scientific climate change knowledge. ► With declining attention, framing disregards climate change, using local knowledge. ► We conclude that frames function as sensemaking devices selectively using knowledge. -- Abstract: Water management and particularly flood defence have a long history of collective action in low-lying countries like the Netherlands. The uncertain but potentially severe impacts of the recent climate change issue (e.g. sea level rise, extreme river discharges, salinisation) amplify the wicked and controversial character of flood safety policy issues. Policy proposals in this area generally involve drastic infrastructural works and long-term investments. They face the difficult challenge of framing problems and solutions in a publicly acceptable manner in ever changing circumstances. In this paper, we analyse and compare (1) how three key policy proposals publicly frame the flood safety issue, (2) the knowledge referred to in the framing and (3) how these frames are rhetorically connected or disconnected as statements in a long-term conversation. We find that (1) framings of policy proposals differ in the way they depict the importance of climate change, the relevant timeframe and the appropriate governance mode; (2) knowledge is selectively mobilised to underpin the different frames and (3) the frames about these proposals position themselves against the background of the previous proposals through rhetorical connections and disconnections. Finally, we discuss how this analysis hints at the importance of processes of powering and puzzling that lead to particular framings towards the public at different historical junctures
Lubrication of rigid ellipsida solids
Hamrock, B. J.; Dowson, D.
1982-01-01
The influence of geometry on the isothermal hydrodynamic film separating two rigid solids was investigated. The minimum film thickness is derived for fully flooded conjunctions by using the Reynolds boundary conditions. It was found that the minimum film thickness had the same speed, viscosity, and load dependence as Kapitza' classical solution. However, the incorporation of Reynolds boundary conditions resulted in an additional geometry effect. Solutions using the parabolic film approximation are compared by using the exact expression for the film in the analysis. Contour plots are known that indicate in detail the pressure developed between the solids.
Rigid inflatable gastrostomy tube malposition
Directory of Open Access Journals (Sweden)
Timothy E. Murray, MB, MCh, MRCS, FFR
2017-12-01
Full Text Available Rigid inflatable gastrostomy (RIG tubes are widely used in contemporary clinical practice for a variety of indications. Insertion of RIG tubes is associated with a high technical success rate and low incidence of mortality. In this case report, a procedural pitfall associated with intraperitoneal-extragastric malposition is described. Rigorous assessment of abdominal radiographs, as well as awareness of the expected appearance of the RIG tube and gastropexy T-fasteners, allows the abdominal radiologist to detect early RIG position in the early postprocedural period. Abdominal radiography is a widely available and inexpensive technique. The high spatial resolution it provides makes it a valuable tool in determining hardware position.
Geometry, rigidity, and group actions
Farb, Benson; Zimmer, Robert J
2011-01-01
The study of group actions is more than a hundred years old but remains to this day a vibrant and widely studied topic in a variety of mathematic fields. A central development in the last fifty years is the phenomenon of rigidity, whereby one can classify actions of certain groups, such as lattices in semi-simple Lie groups. This provides a way to classify all possible symmetries of important spaces and all spaces admitting given symmetries. Paradigmatic results can be found in the seminal work of George Mostow, Gergory Margulis, and Robert J. Zimmer, among others.The p
Frame independent cosmological perturbations
Energy Technology Data Exchange (ETDEWEB)
Prokopec, Tomislav; Weenink, Jan, E-mail: t.prokopec@uu.nl, E-mail: j.g.weenink@uu.nl [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Leuvenlaan 4, 3585 CE Utrecht (Netherlands)
2013-09-01
We compute the third order gauge invariant action for scalar-graviton interactions in the Jordan frame. We demonstrate that the gauge invariant action for scalar and tensor perturbations on one physical hypersurface only differs from that on another physical hypersurface via terms proportional to the equation of motion and boundary terms, such that the evolution of non-Gaussianity may be called unique. Moreover, we demonstrate that the gauge invariant curvature perturbation and graviton on uniform field hypersurfaces in the Jordan frame are equal to their counterparts in the Einstein frame. These frame independent perturbations are therefore particularly useful in relating results in different frames at the perturbative level. On the other hand, the field perturbation and graviton on uniform curvature hypersurfaces in the Jordan and Einstein frame are non-linearly related, as are their corresponding actions and n-point functions.
Seismic Performance of Steel Frames with Semirigid Connections
Directory of Open Access Journals (Sweden)
Iman Faridmehr
2017-01-01
Full Text Available The nonlinear stiffness matrix method was incorporated to investigate the structural performance of steel portal frames with semirigid connections. A portal frame with unstiffened extended end-plate connection was designed to demonstrate the adequacy of the proposed method. Besides, the seismic performance of steel portal frames with semirigid connections was investigated through time history analysis where kinematic hysteresis model was assigned to semirigid connections to account for energy dissipation and unloading stiffness. Based on the results of the study, it was found that generally semirigid connections influenced the force distribution which resulted in the decrease in base shear and lighter frame compared to the rigid one. The results also indicated that there was no direct relationship between maximum displacement at the top and connection stiffness in high-rise frames.
Frame on frames: an annotated bibliography
International Nuclear Information System (INIS)
Wright, T.; Tsao, H.J.
1983-01-01
The success or failure of any sample survey of a finite population is largely dependent upon the condition and adequacy of the list or frame from which the probability sample is selected. Much of the published survey sampling related work has focused on the measurement of sampling errors and, more recently, on nonsampling errors to a lesser extent. Recent studies on data quality for various types of data collection systems have revealed that the extent of the nonsampling errors far exceeds that of the sampling errors in many cases. While much of this nonsampling error, which is difficult to measure, can be attributed to poor frames, relatively little effort or theoretical work has focused on this contribution to total error. The objective of this paper is to present an annotated bibliography on frames with the hope that it will bring together, for experimenters, a number of suggestions for action when sampling from imperfect frames and that more attention will be given to this area of survey methods research
EO framing flight test results
Lareau, Andre G.
1995-09-01
Recon/Optical, Inc. (ROI) has pioneered the electro-optical (E-O) framing generation of sensors with the CA-260, a KS-87 form/fit camera with a wafer-scale focal plane array (FPA) containing a patented, on-chip, forward motion compensation (FMC) architecture. The technology has now matured to the state where production E-O framing cameras are form/fit replacing their former film counterparts. During this interim production phase, flight demonstrations and tests are continuing to prove that E-O framing produces high-quality imagery, is robust to various platforms and mission tactics, interoperable with existing and planned C3I architectures, affordable and available, and meets the war-fighters needs. This paper discusses flight test results of the CA-260 E-O framing sensor flown in the F-14A TARPS during September 1994. This demonstration provided some unique imagery permitting a comparison of low-light level, in-flight FMC-on versus FMC-off performance. A first-level comparison of the resulting imagery based upon predicted FMC performance and post- processing numerical analysis is presented. The results indicae that the patented FMC architecture performed as predicted, and that for low-light conditions resulting in limited SNR images, on-chip FMC can provide a significant image quality improvement over post- processing alternatives.
DEFF Research Database (Denmark)
Hansen, Ernst Jan de Place; Brandt, Erik
2010-01-01
A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...
American Inst. of Steel Construction, Inc., New York, NY.
In view of the cost of structural framing for school buildings, ten steel-framed schools are examined to review the economical advantages of steel for school construction. These schools do not resemble each other in size, shape, arrangement or unit cost; some are original in concept and architecture, and others are conservative. Cost and…
Edwards, Michael Todd; Cox, Dana C.
2011-01-01
In this article, the authors explore framing, a non-multiplicative technique commonly employed by students as they construct similar shapes. When students frame, they add (or subtract) a "border" of fixed width about a geometric object. Although the approach does not yield similar shapes in general, the mathematical underpinnings of…
Multimodal news framing effects
Powell, T.E.
2017-01-01
Visuals in news media play a vital role in framing citizens’ political preferences. Yet, compared to the written word, visual images are undervalued in political communication research. Using framing theory, this thesis redresses the balance by studying the combined, or multimodal, effects of visual
DEFF Research Database (Denmark)
Knudsen, Sanne
2017-01-01
The humanities, the natural and social sciences all represent advanced and systematic knowledge production—and they all receive public funding for doing so. However, although the field of public understanding of science has been well established for decades, similar research attention has not been...... directed at the humanities. The purpose of this study is to argue the case for further research of public understanding of the humanities and to take a first step in that direction by presenting a study of the framing of the humanities in Danish print news media. Different framings of the humanities...... are analyzed. Despite the differences in the issue-specific frames, the generic framing of the humanities shared by most articles is as follows: 75% explicitly frame the humanities as deficit, while the remaining 25% are more neutral. Consequently, if newspapers constitute the only source of information...
Cracking of open traffic rigid pavement
Niken Chatarina; Siswanto Yudi; Widodo; Tjahjono Elly
2017-01-01
The research is done by observing the growth of real structure cracking in Natar, Lampung, Indonesia compared to C. Niken’s et al research and literature study. The rigid pavement was done with open traffic system. There are two main crack types on Natar rigid pavement: cracks cross the road, and cracks spreads on rigid pavement surface. The observation of cracks was analyzed by analyzing material, casting, curing, loading and shrinkage mechanism. The relationship between these analysis and s...
Parametrizing Finite Frames and Optimal Frame Completions
2012-12-01
n = n ′( ∫ ∞ −∞ n pn(n)dn )( ∫ ∞ −∞ n′ pn′(n′)dn′ ) n , n′ = var (n) n = n′ 0 n , n′ . (6.3) Substituting (6.3) into (6.2) gives...frames,” in Proceedings of the SPIE Conference on Wavelets : Applications in Signal and Image Processing X, 371-380 (November 2003). [10] Casazza, P. G
Mooring and ground handling rigid airships
Walker, H., Jr.
1975-01-01
The problems of mooring and ground handling rigid airships are discussed. A brief history of Mooring and Ground Handling Rigid Airships from July 2, 1900 through September 1, 1939 is included. Also a brief history of ground handling developments with large U. S. Navy nonrigid airships between September 1, 1939 and August 31, 1962 is included wherein developed equipment and techniques appear applicable to future large rigid airships. Finally recommendations are made pertaining to equipment and procedures which appear desirable and feasible for future rigid airship programs.
Rigidizing Inflatable Deployable Dwelling (RIDD), Phase I
National Aeronautics and Space Administration — By combining thin thermoplastic films, woven Vectran reinforcements, and heat a reliable, deployable, rigidizing space habitat can be created. Although much research...
Wei, Meng; Xu, Pengxiang; Yuan, Yizhong; Tian, Xiaohui; Sun, Jinyu; Lin, Jiaping
2018-03-28
A coarse-grained model-based molecular dynamics simulation was employed to investigate the mechanical properties of NR-graft-rigid-polymer/rigid-polymer systems (N 30 -g-(R 3 ) 6 /R 10 ). An external factor (the strain rate) as well as internal factors such as the nonbonding interaction strength, the proportion of rigid polymers, and architecture parameters (the length and number of graft chains in a molecule) were examined for their effect on the tensional behavior of N 30 -g-(R 3 ) 6 /R 10 systems. Simulation results show that a higher strain rate can promote the enhancement of mechanical performance, such as a higher modulus or yield stress. Moreover, the stress and modulus increase with an increase of the nonbonding interaction strength within rigid polymers or of the rigid polymer proportion in the systems. However, the increasing stress was found to reach a limit with a continuously increasing rigid polymer proportion. On increasing the number of graft chains in a molecule, the stress increases at small strains. However, at large strains, the evident increase in stress was found in systems in which a graft molecule has longer graft chains. In addition, our research shows that N 30 -g-(R 3 ) 6 /R 10 blends exhibit improved mechanical properties and better compatibilities relative to N 30 /R 10 , which is consistent with the experimental results. Lastly, comparisons with experimental observations were also made to ensure the rationality of the simulation results. Overall, bond stretching, bond orientation, and nonbonding interactions were found to be crucial in governing the mechanical properties of the N 30 -g-(R 3 ) 6 /R 10 systems. These findings may provide important information for further experimental and simulation studies of NR hybrid materials.
NoRMCorre: An online algorithm for piecewise rigid motion correction of calcium imaging data.
Pnevmatikakis, Eftychios A; Giovannucci, Andrea
2017-11-01
Motion correction is a challenging pre-processing problem that arises early in the analysis pipeline of calcium imaging data sequences. The motion artifacts in two-photon microscopy recordings can be non-rigid, arising from the finite time of raster scanning and non-uniform deformations of the brain medium. We introduce an algorithm for fast Non-Rigid Motion Correction (NoRMCorre) based on template matching. NoRMCorre operates by splitting the field of view (FOV) into overlapping spatial patches along all directions. The patches are registered at a sub-pixel resolution for rigid translation against a regularly updated template. The estimated alignments are subsequently up-sampled to create a smooth motion field for each frame that can efficiently approximate non-rigid artifacts in a piecewise-rigid manner. Existing approaches either do not scale well in terms of computational performance or are targeted to non-rigid artifacts arising just from the finite speed of raster scanning, and thus cannot correct for non-rigid motion observable in datasets from a large FOV. NoRMCorre can be run in an online mode resulting in comparable to or even faster than real time motion registration of streaming data. We evaluate its performance with simple yet intuitive metrics and compare against other non-rigid registration methods on simulated data and in vivo two-photon calcium imaging datasets. Open source Matlab and Python code is also made available. The proposed method and accompanying code can be useful for solving large scale image registration problems in calcium imaging, especially in the presence of non-rigid deformations. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
DEFF Research Database (Denmark)
Anderson, Joel; Antalikova, Radka
2014-01-01
Denmark is currently experiencing the highest immigration rate in its modern history. Population surveys indicate that negative public attitudes toward immigrants actually stem from attitudes toward their (perceived) Islamic affiliation. We used a framing paradigm to investigate the explicit...... and implicit attitudes of Christian and Atheist Danes toward targets framed as Muslims or as immigrants. The results showed that explicit and implicit attitudes were more negative when the target was framed as a Muslim, rather than as an immigrant. Interestingly, implicit attitudes were qualified...
Geometry and the onset of rigidity in a disordered network
Vermeulen, Mathijs F. J.; Bose, Anwesha; Storm, Cornelis; Ellenbroek, Wouter G.
2017-11-01
Disordered spring networks that are undercoordinated may abruptly rigidify when sufficient strain is applied. Since the deformation in response to applied strain does not change the generic quantifiers of network architecture, the number of nodes and the number of bonds between them, this rigidity transition must have a geometric origin. Naive, degree-of-freedom-based mechanical analyses such as the Maxwell-Calladine count or the pebble game algorithm overlook such geometric rigidity transitions and offer no means of predicting or characterizing them. We apply tools that were developed for the topological analysis of zero modes and states of self-stress on regular lattices to two-dimensional random spring networks and demonstrate that the onset of rigidity, at a finite simple shear strain γ★, coincides with the appearance of a single state of self-stress, accompanied by a single floppy mode. The process conserves the topologically invariant difference between the number of zero modes and the number of states of self-stress but imparts a finite shear modulus to the spring network. Beyond the critical shear, the network acquires a highly anisotropic elastic modulus, resisting further deformation most strongly in the direction of the rigidifying shear. We confirm previously reported critical scaling of the corresponding differential shear modulus. In the subcritical regime, a singular value decomposition of the network's compatibility matrix foreshadows the onset of rigidity by way of a continuously vanishing singular value corresponding to the nascent state of self-stress.
Global Vertical Reference Frame
Czech Academy of Sciences Publication Activity Database
Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.
2004-01-01
Roč. 33, - (2004), s. 404-407 ISSN 1436-3445 Institutional research plan: CEZ:AV0Z1003909 Keywords : geopotential WO * vertical systems * global vertical frame Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Evaluating a method for automated rigid registration
DEFF Research Database (Denmark)
Darkner, Sune; Vester-Christensen, Martin; Larsen, Rasmus
2007-01-01
We evaluate a novel method for fully automated rigid registration of 2D manifolds in 3D space based on distance maps, the Gibbs sampler and Iterated Conditional Modes (ICM). The method is tested against the ICP considered as the gold standard for automated rigid registration. Furthermore...
On transforms between Gabor frames and wavelet frames
DEFF Research Database (Denmark)
Christensen, Ole; Goh, Say Song
2013-01-01
We describe a procedure that enables us to construct dual pairs of wavelet frames from certain dual pairs of Gabor frames. Applying the construction to Gabor frames generated by appropriate exponential Bsplines gives wavelet frames generated by functions whose Fourier transforms are compactly...... supported splines with geometrically distributed knot sequences. There is also a reverse transform, which yields pairs of dual Gabor frames when applied to certain wavelet frames....
Topological orders in rigid states
International Nuclear Information System (INIS)
Wen, X.G.
1990-01-01
The authors study a new kind of ordering topological order in rigid states (the states with no local gapless excitations). This paper concentrates on characterization of the different topological orders. As an example the authors discuss in detail chiral spin states of 2+1 dimensional spin systems. Chiral spin states are described by the topological Chern-Simons theories in the continuum limit. The authors show that the topological orders can be characterized by a non-Abelian gauge structure over the moduli space which parametrizes a family of the model Hamiltonians supporting topologically ordered ground states. In 2 + 1 dimensions, the non-Abelian gauge structure determines possible fractional statistics of the quasi-particle excitations over the topologically ordered ground states. The dynamics of the low lying global excitations is shown to be independent of random spatial dependent perturbations. The ground state degeneracy and the non-Abelian gauge structures discussed in this paper are very robust, even against those perturbations that break translation symmetry. The authors also discuss the symmetry properties of the degenerate ground states of chiral spin states. The authors find that some degenerate ground states of chiral spin states on torus carry non-trivial quantum numbers of the 90 degrees rotation
Semiclassical Theory of Spectral Rigidity
Berry, M. V.
1985-08-01
The spectral rigidity Δ(L) of a set of quantal energy levels is the mean square deviation of the spectral staircase from the straight line that best fits it over a range of L mean level spacings. In the semiclassical limit (hslash-> 0), formulae are obtained giving Δ(L) as a sum over classical periodic orbits. When L ~= Lmax, where Lmax ~ hslash-(N-1) for a system of N freedoms, Δ(L) is shown to display the following universal behaviour as a result of properties of very long classical orbits: if the system is classically integrable (all periodic orbits filling tori), Δ(L) = 1/15L (as in an uncorrelated (Poisson) eigenvalue sequence); if the system is classically chaotic (all periodic orbits isolated and unstable) and has no symmetry, Δ(L) = ln L/2π^2 + D if 1 ~= L ~= Lmax (as in the gaussian unitary ensemble of random-matrix theory); if the system is chaotic and has time-reversal symmetry, Δ(L) = ln L/π^2 + E if 1 ~= L ~= Lmax (as in the gaussian orthogonal ensemble). When L >> Lmax, Δ(L) saturates non-universally at a value, determined by short classical orbits, of order hslash-(N-1) for integrable systems and ln (hslash-1) for chaotic systems. These results are obtained by using the periodic-orbit expansion for the spectral density, together with classical sum rules for the intensities of long orbits and a semiclassical sum rule restricting the manner in which their contributions interfere. For two examples Δ(L) is studied in detail: the rectangular billiard (integrable), and the Riemann zeta function (assuming its zeros to be the eigenvalues of an unknown quantum system whose unknown classical limit is chaotic).
Operator representations of frames
DEFF Research Database (Denmark)
Christensen, Ole; Hasannasab, Marzieh
2017-01-01
The purpose of this paper is to consider representations of frames {fk}k∈I in a Hilbert space ℋ of the form {fk}k∈I = {Tkf0}k∈I for a linear operator T; here the index set I is either ℤ or ℒ0. While a representation of this form is available under weak conditions on the frame, the analysis...... of the properties of the operator T requires more work. For example it is a delicate issue to obtain a representation with a bounded operator, and the availability of such a representation not only depends on the frame considered as a set, but also on the chosen indexing. Using results from operator theory we show...... that by embedding the Hilbert space ℋ into a larger Hilbert space, we can always represent a frame via iterations of a bounded operator, composed with the orthogonal projection onto ℋ. The paper closes with a discussion of an open problem concerning representations of Gabor frames via iterations of a bounded...
DEFF Research Database (Denmark)
Bruggemann, Michael; Humprecht, Edda; Kleis, Rasmus
2016-01-01
This article argues that discourses of a newspaper crisis should not be regarded simply as descriptions of the actual state of the press but also as a means by which strategic actors frame the situation. The emerging frames can have substantial consequences for media policy making. The study...... as well as a qualitative analysis of policy documents and relevant media coverage. The study demonstrates that debates on the newspaper crisis are only partly influenced by (1) economic realities and (2) media policy traditions in the six countries but also reflect (3) the strategic motives of powerful...... actors and (4) the diffusion of frames across borders, particularly those coming from the United States. A transnationally uniform paradigm emerges according to which the state is expected to play the role of a benevolent but mostly passive bystander, while media companies are expected to tackle...
New Characterizations of Fusion Frames (Frames of Subspaces)
Indian Academy of Sciences (India)
In this article, we give new characterizations of fusion frames, on the properties of their synthesis operators, on the behavior of fusion frames under bounded operators with closed range, and on erasures of subspaces of fusion frames. Furthermore we show that every fusion frame is the image of an orthonormal fusion basis ...
New characterizations of fusion frames (frames of subspaces)
Indian Academy of Sciences (India)
Abstract. In this article, we give new characterizations of fusion frames, on the properties of their synthesis operators, on the behavior of fusion frames under bounded operators with closed range, and on erasures of subspaces of fusion frames. Furthermore we show that every fusion frame is the image of an orthonormal ...
The quasi-rigid premise in Precambrian tectonics
Piper, J. D. A.
1991-12-01
A simple test of the proposition that movements between multiple continental fragments driven by plate tectonics took place during the earlier eons of geological time is presented. A random distribution is derived when the collective palaeomagnetic poles are rotated into any quasi-rigid reconstruction. The test surmounts the most serious limitation of Precambrian palaeomagnetic data, namely, that the ages of magnetization are mostly poorly known. Confirmation of the quasi-rigid premise is derived in a debased form, but is not suppressed, by the deficiencies of the database. This palaeomagnetic constraint explains the distinctive isotopic, geochemical, and lithofacies signatures of the Proterozoid eon and is independently supported by the trend and long temporal continuity of crustal lineaments.
DEFF Research Database (Denmark)
Hansen, Ernst Jan de Place; Brandt, Erik
2010-01-01
A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...... is reduced. To investigate the possibilities, full-size wall elements with wooden cladding and different cavity design, type of cladding and type of wind barrier were exposed to natural climate on the outside and to a humid indoor climate on the inside. During the exposure period parts of the vapour barrier...
DEFF Research Database (Denmark)
Just, Sine Nørholm; Mouton, Nicolaas T.O.
2014-01-01
between competing frames leads to the conclusion that this political “blame game” is related to struggles over how to define the scandal, how to conceptualize its causes, and policy recommendations. Banks may have lost the battle of “Liborgate,” but the war over the meaning of financial culture is far...... from over. Originality/value – The paper is theoretically and methodologically original in its combination of the theories of framing and stasis, and it provides analytical insights into how sense is made of financial culture in the wake of the financial crisis....
International Nuclear Information System (INIS)
Joshi, V.M.; Agashe, Alok; Bairi, B.R.
1993-01-01
This report provides technical description regarding the Video Frame Processor (VFP) developed at Bhabha Atomic Research Centre. The instrument provides capture of video images available in CCIR format. Two memory planes each with a capacity of 512 x 512 x 8 bit data enable storage of two video image frames. The stored image can be processed on-line and on-line image subtraction can also be carried out for image comparisons. The VFP is a PC Add-on board and is I/O mapped within the host IBM PC/AT compatible computer. (author). 9 refs., 4 figs., 19 photographs
Frame scaling function sets and frame wavelet sets in Rd
International Nuclear Information System (INIS)
Liu Zhanwei; Hu Guoen; Wu Guochang
2009-01-01
In this paper, we classify frame wavelet sets and frame scaling function sets in higher dimensions. Firstly, we obtain a necessary condition for a set to be the frame wavelet sets. Then, we present a necessary and sufficient condition for a set to be a frame scaling function set. We give a property of frame scaling function sets, too. Some corresponding examples are given to prove our theory in each section.
Soft soils reinforced by rigid vertical inclusions
Directory of Open Access Journals (Sweden)
Iulia-Victoria NEAGOE
2013-12-01
Full Text Available Reinforcement of soft soils by rigid vertical inclusions is an increasingly used technique over the last few years. The system consists of rigid or semi-rigid vertical inclusions and a granular platform for the loads transfer from the structure to the inclusions. This technique aims to reduce the differential settlements both at ground level as below the structure. Reinforcement by rigid inclusions is mainly used for foundation works for large commercial and industrial platforms, storage tanks, wastewater treatment plants, wind farms, bridges, roads, railway embankments. The subject is one of interest as it proves the recently concerns at international level in research and design; however, most studies deal more with the static behavior and less with the dynamic one.
Rigid pricing and rationally inattentive consumer
Czech Academy of Sciences Publication Activity Database
Matějka, Filip
158 B, July (2015), s. 656-678 ISSN 0022-0531 Institutional support: RVO:67985998 Keywords : rational inattention * imperfect information * nominal rigidity Subject RIV: AH - Economics Impact factor: 1.097, year: 2015
Rigid pricing and rationally inattentive consumer
Czech Academy of Sciences Publication Activity Database
Matějka, Filip
158 B, July (2015), s. 656-678 ISSN 0022-0531 Institutional support: PRVOUK-P23 Keywords : rational inattention * imperfect information * nominal rigidity Subject RIV: AH - Economics Impact factor: 1.097, year: 2015
Analysis of Switched-Rigid Floating Oscillator
Directory of Open Access Journals (Sweden)
Prabhakar R. Marur
2009-01-01
Full Text Available In explicit finite element simulations, a technique called deformable-to-rigid (D2R switching is used routinely to reduce the computation time. Using the D2R option, the deformable parts in the model can be switched to rigid and reverted back to deformable when needed during the analysis. The time of activation of D2R however influences the overall dynamics of the system being analyzed. In this paper, a theoretical basis for the selection of time of rigid switching based on system energy is established. A floating oscillator problem is investigated for this purpose and closed-form analytical expressions are derived for different phases in rigid switching. The analytical expressions are validated by comparing the theoretical results with numerical computations.
Modeling Decomposition of Unconfined Rigid Polyurethane Foam
National Research Council Canada - National Science Library
Hobbs, Michael
1999-01-01
The decomposition of unconfined rigid polyurethane foam has been modeled by a kinetic bond-breaking scheme describing degradation of a primary polymer and formation of a thermally stable secondary polymer...
Frames and extension problems I
DEFF Research Database (Denmark)
Christensen, Ole
2014-01-01
In this article we present a short survey of frame theory in Hilbert spaces. We discuss Gabor frames and wavelet frames and set the stage for a discussion of various extension principles; this will be presented in the article Frames and extension problems II (joint with H.O. Kim and R.Y. Kim)....
Directory of Open Access Journals (Sweden)
Ioan URSU
2012-09-01
Full Text Available The paper brought to light a previous result of the author, used in the design of hydraulicservos actuating flight controls of the airplanes IAR 93 and IAR 99. The results highlights theimportance of the the kinematics of the rigid feedback linkage of the hydraulic servo in anaeroservoelastic frame.
DEFF Research Database (Denmark)
Kau, Edvin
2012-01-01
Unfolding his story very gradually and arousing the viewer’s curiosity, Sitaru invites the audience to investigate the parents’ and the boy’s mutual positions in their small flat, as well as the various layers of their conversations, through such means as framing, editing style, and the use...
Williams, Laurence; Macnaghten, Philip; Davies, Richard; Curtis, Sarah
2017-01-01
The prospect of fracking in the United Kingdom has been accompanied by significant public unease. We outline how the policy debate is being framed by UK institutional actors, finding evidence of a dominant discourse in which the policy approach is defined through a deficit model of public
DEFF Research Database (Denmark)
Haastrup, Helle Kannik
2016-01-01
How is the global media event of the Oscars localised through the talk show on Danish television? How are both the mediated film star and the special brand of Hollywood celebrity culture addressed by the cultural intermediaries in the Danish framing? These are the questions I propose to answer...
DEFF Research Database (Denmark)
Olesen, Mette
2014-01-01
In Europe, there has been a strong political will to implement light rail. This article contributes to the knowledge concerning policies around light rail by analysing how local actors frame light rail projects and which rationalities and arguments are present in this decision-making process...
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
2013-01-01
). In this process, framing (Evans & Green 2006; Fillmore 1982; Kövecses 2006; Lakoff 1987, 1996) plays a salient role in conceptualising the profile and qualities of the preferred candidate, drawing on established cultural models of what constitutes the perfect leader. Thus, in a Danish setting we may talk of two...
Global Vertical Reference Frame
Czech Academy of Sciences Publication Activity Database
Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.
-, č. 5 (2009), s. 53-63 ISSN 1801-8483 R&D Projects: GA ČR GA205/08/0328 Institutional research plan: CEZ:AV0Z10030501 Keywords : sea surface topography * satellite altimetry * vertical frames Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Institutional Justification in Frames
DEFF Research Database (Denmark)
Baden, Christian; Schultz, Friederike
Crises – such as the BP oil spill in the Gulf of Mexico (2010) – are moments in which conventional interpretations break down. This paper analyzes the dynamics of the re-construction and stabilization of meaning in the public debate and assesses how BP’s strategic framing affected the emerging...
National Research Council Canada - National Science Library
Saywell, John; Anastakis, Dimitry; Bryden, Penny E
2009-01-01
... the pervasive effects that federalism has on Canadian politics, economics, culture, and history, and provide a detailed framework in which to understand contemporary federalism. Written in honour of John T. Saywell's half-century of accomplished and influential scholarly work and teaching, Framing Canadian Federalism is a timely and fitting t...
Sparse Matrices in Frame Theory
DEFF Research Database (Denmark)
Lemvig, Jakob; Krahmer, Felix; Kutyniok, Gitta
2014-01-01
Frame theory is closely intertwined with signal processing through a canon of methodologies for the analysis of signals using (redundant) linear measurements. The canonical dual frame associated with a frame provides a means for reconstruction by a least squares approach, but other dual frames...... yield alternative reconstruction procedures. The novel paradigm of sparsity has recently entered the area of frame theory in various ways. Of those different sparsity perspectives, we will focus on the situations where frames and (not necessarily canonical) dual frames can be written as sparse matrices...
Wavelet frames and their duals
DEFF Research Database (Denmark)
Lemvig, Jakob
2008-01-01
This thesis is concerned with computational and theoretical aspects of wavelet frame analysis in higher dimensions and, in particular, with the study of so-called dual frames of wavelet frames. A frame is a system of "simple" functions or building blocks which deliver ways of analyzing signals....... The signals are then represented by linear combinations of the building blocks with coefficients found by an associated frame, called a dual frame. A wavelet frame is a frame where the building blocks are stretched (dilated) and translated versions of a single function; such a frame is said to have wavelet...... structure. The dilation of the wavelet building blocks in higher dimension is done via a square matrix which is usually taken to be integer valued. In this thesis we step away from the "usual" integer, expansive dilation and consider more general, expansive dilations. In most applications of wavelet frames...
Rigid Body Sampling and Individual Time Stepping for Rigid-Fluid Coupling of Fluid Simulation
Directory of Open Access Journals (Sweden)
Xiaokun Wang
2017-01-01
Full Text Available In this paper, we propose an efficient and simple rigid-fluid coupling scheme with scientific programming algorithms for particle-based fluid simulation and three-dimensional visualization. Our approach samples the surface of rigid bodies with boundary particles that interact with fluids. It contains two procedures, that is, surface sampling and sampling relaxation, which insures uniform distribution of particles with less iterations. Furthermore, we present a rigid-fluid coupling scheme integrating individual time stepping to rigid-fluid coupling, which gains an obvious speedup compared to previous method. The experimental results demonstrate the effectiveness of our approach.
EXPERIMENTAL STUDY OF THE BEARING CAPACITY OF SPATIAL METAL FRAMES
Directory of Open Access Journals (Sweden)
Serpik Igor' Naftol'evich
2012-10-01
Full Text Available In the article, the authors describe the principal findings of the experimental study of destruction of spatial frames made of closed-profile steel rods. Six samples of frames were tested through the application of a kinematic loading scheme. Values of forces, displacements and deformations were measured over the time. Each sample was brought to the state when the load reached its maximal value. Thereafter, the load intensity was reduced to 0.6...0.7 of its maximal value. It was identified that the destruction of rods in the event of combined stress was similar to the formation of plastic hinges in the course of regular bending. In some cases, cracks were formed in the zones of plastic hinges. This process did not cause complete destruction of frames. Destruction-related conditions were also assessed by the quasi-rigidity method implemented in STARK ES 2009 software package. The input data were used to perform failure, bending and torsion tests of steel pipes. The experiments and calculations have proven that in this case the process of destruction can be considered in accordance with the limit equilibrium method by taking account of formation of spatial plastic hinges. The quasi-rigidity method can be employed to identify the maximal load that the frames can bear.
Patient preferences and comparative ocular responses to rigid and soft contact lenses.
Fonn, D; Gauthier, C A; Pritchard, N
1995-12-01
Patient preferences and ocular responses were compared between rigid and soft contact lenses by randomly fitting 32 neophyte subjects with a rigid lens in 1 eye and a soft lens in the contralateral eye. Twenty-seven of 32 subjects completed the 3-month study and 16 subjects were willing to continue for an additional 3-month extension. Subjects preferred the comfort and handling of the soft lens but preferred the vision provided by the rigid lens and initially its ease of maintenance. There was also a marked preference for the soft lens when all aspects of lens wear were compared. Objectively, the rigid lenses were responsible for more ocular changes than the soft lenses. Palpebral aperture sizes of the rigid gas permeable (RGP) wearing eyes decreased significantly (0.5 mm; p lens wearing eyes. The incidence of corneal staining was significantly greater in the rigid lens wearing eye (50% RGP vs. 22% soft) but limbal injection was greater in the soft lens wearing eye (18% soft vs. 6% RGP). Refractive sphere, cylinder, and corneal astigmatism decreased in the rigid lens wearing eye after 3 months. This daily wear clinical trial has shown a marked subjective preference for wearing soft lenses with fewer short-term ocular effects.
Some relationship between G-frames and frames
Directory of Open Access Journals (Sweden)
Mehdi Rashidi-Kouchi
2015-06-01
Full Text Available In this paper we proved that every g-Riesz basis for Hilbert space $H$ with respect to $K$ by adding a condition is a Riesz basis for Hilbert $B(K$-module $B(H,K$. This is an extension of [A. Askarizadeh,M. A. Dehghan, {em G-frames as special frames}, Turk. J. Math., 35, (2011 1-11]. Also, we derived similar results for g-orthonormal and orthogonal bases. Some relationships between dual frame, dual g-frame and exact frame and exact g-frame are presented too.
Rigid Body Energy Minimization on Manifolds for Molecular Docking.
Mirzaei, Hanieh; Beglov, Dmitri; Paschalidis, Ioannis Ch; Vajda, Sandor; Vakili, Pirooz; Kozakov, Dima
2012-11-13
Virtually all docking methods include some local continuous minimization of an energy/scoring function in order to remove steric clashes and obtain more reliable energy values. In this paper, we describe an efficient rigid-body optimization algorithm that, compared to the most widely used algorithms, converges approximately an order of magnitude faster to conformations with equal or slightly lower energy. The space of rigid body transformations is a nonlinear manifold, namely, a space which locally resembles a Euclidean space. We use a canonical parametrization of the manifold, called the exponential parametrization, to map the Euclidean tangent space of the manifold onto the manifold itself. Thus, we locally transform the rigid body optimization to an optimization over a Euclidean space where basic optimization algorithms are applicable. Compared to commonly used methods, this formulation substantially reduces the dimension of the search space. As a result, it requires far fewer costly function and gradient evaluations and leads to a more efficient algorithm. We have selected the LBFGS quasi-Newton method for local optimization since it uses only gradient information to obtain second order information about the energy function and avoids the far more costly direct Hessian evaluations. Two applications, one in protein-protein docking, and the other in protein-small molecular interactions, as part of macromolecular docking protocols are presented. The code is available to the community under open source license, and with minimal effort can be incorporated into any molecular modeling package.
Crack identification for rigid pavements using unmanned aerial vehicles
Bahaddin Ersoz, Ahmet; Pekcan, Onur; Teke, Turker
2017-09-01
Pavement condition assessment is an essential piece of modern pavement management systems as rehabilitation strategies are planned based upon its outcomes. For proper evaluation of existing pavements, they must be continuously and effectively monitored using practical means. Conventionally, truck-based pavement monitoring systems have been in-use in assessing the remaining life of in-service pavements. Although such systems produce accurate results, their use can be expensive and data processing can be time consuming, which make them infeasible considering the demand for quick pavement evaluation. To overcome such problems, Unmanned Aerial Vehicles (UAVs) can be used as an alternative as they are relatively cheaper and easier-to-use. In this study, we propose a UAV based pavement crack identification system for monitoring rigid pavements’ existing conditions. The system consists of recently introduced image processing algorithms used together with conventional machine learning techniques, both of which are used to perform detection of cracks on rigid pavements’ surface and their classification. Through image processing, the distinct features of labelled crack bodies are first obtained from the UAV based images and then used for training of a Support Vector Machine (SVM) model. The performance of the developed SVM model was assessed with a field study performed along a rigid pavement exposed to low traffic and serious temperature changes. Available cracks were classified using the UAV based system and obtained results indicate it ensures a good alternative solution for pavement monitoring applications.
DEFF Research Database (Denmark)
Degel, Henrik; Jansen, Teunis
2006-01-01
. Development and test of software modules can be done once and reused by all. The biggest challenge in this is not technical – it is in organisation, coordination and trust. This challenge has been addressed by FishFrame - a web-based datawarehouse application. The “bottom-up” approach with maximum involvement...... for fixed reoccurring tasks like assessment working groups, data are often late and the quality can be unsatisfactory. The current situation of this “semi-manual distributed datawarehouse” can be improved technically. Methods for quality control, raising and calculation can be discussed and unified...... value to users and in the end improves the way we work with our data. FishFrame version 4.2 is presented and the lessons learned from the process are discussed....
A United Algorithm for Limit State Determination of Frames with Semi-Rigid Connections
Nguyen, Dang-Hung; Hoang, Van Long
2010-01-01
A computer program is proposed to calculate the limit states of the frameworks with the following problems: Elastic analysis, Limit analysis, First-order and second-order elastic-plastic analysis, Shakedown analysis, Optimization-Limit, Optimization-Shakedown have been realised by Nguyen-Dang Hung in 1980, namely CEPAO. All of these calculations are connected with the problem of automatic search of independent mechanism in the sense of limit analysis. This permits to solve a lot of problems i...
Ortega-Cerda, Joaquim; Seip, Kristian
2000-01-01
We solve the problem of Duffin and Schaeffer (1952) of characterizing those sequences of real frequencies which generate Fourier frames. Equivalently, we characterize the sampling sequences for the Paley-Wiener space. The key step is to connect the problem with de Branges' theory of Hilbert spaces of entire functions. We show that our description of sampling sequences permits us to obtain a classical inequality of H. Landau as a consequence of Pavlov's description of Riesz bases of complex ex...
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
2012-01-01
Danish bank, Danske Bank, during the 2008 financial crisis and hence in shaping its image projected to the public. Through the study of a number of semantic frames adopted by the Danish print press and those adopted by the Bank, this article will argue for the constructions of the press putting...... considerable strain on the Bank and its image, leading it to reconsider its previous strategy of denial of responsibility...
International Nuclear Information System (INIS)
Kalibjian, R.; Chong, Y.P.; Prono, D.S.; Cavagnolo, H.R.
1984-06-01
The ATA provides an electron beam pulse of 70-ns duration at a 1-Hz rate. Our present optical diagnostics technique involve the imaging of the visible light generated by the beam incident onto the plant of a thin sheet of material. It has already been demonstrated that the light generated has a sufficiently fast temporal reponse in performing beam diagnostics. Notwithstanding possible beam emittance degradation due to scattering in the thin sheet, the observation of beam spatial profiles with relatively high efficiencies has provided data complementary to that obtained from beam wall current monitors and from various x-ray probes and other electrical probes. The optical image sensor consists of a gated, intensified television system. The gate pulse of the image intensifier can be appropriately delayed to give frames that are time-positioned from the head to the tail of the beam with a minimum gate time of 5-ns. The spatial correlation of the time frames from pulse to pulse is very good for a stable electron beam; however, when instabilities do occur, it is difficult to properly assess the spatial composition of the head and the tail of the beam on a pulse-to-pulse basis. Multiple gating within a pulse duration becomes desirable but cannot be performed because the recycle time (20-ms) of the TV system is much longer than the beam pulse. For this reason we have developed an optical-loop framing technique that will allow the recording of two frames within one pulse duration with our present gated/intensified TV system
DEFF Research Database (Denmark)
Christensen, Ole; Heil, Christopher; Deng, Baiqiao
1999-01-01
A Gabor system is a set of time-frequency shifts S(g, Lambda) = {e(2 pi ibx) g(x - a)}((a,b)is an element of Lambda) of a function g is an element of L-2(R-d). We prove that if a finite union of Gabor systems boolean (ORk=1S)-S-r(g(k), Lambda(k)) forms a frame for L-2(R-d) then the lower and upper...
DEFF Research Database (Denmark)
Christensen, Ole; Heil, C.; Deng, B.
1997-01-01
A Gabor system is a set of time-frequency shifts$S(g,\\Lambda) = \\{e^{2\\pi i b x} g(x-a)\\}_{(a,b) \\in \\Lambda}$of a function $g \\in L^2({\\bold R}^d)$.We prove that if a finite union of Gabor systems$\\bigcup_{k=1}^r S(g_k,\\Lambda_k)$, with arbitrary sequences $\\Lambda_k$,forms a frame for $L^2({\\bold...
Adopting flexibility of the end-plate connections in steel moment frames
Ghassemieh, M.; Baei, Mahmoud; Kari, Amir; Goudarzi, A.; Laefer, Debra F.
2015-01-01
The majority of connections in moment resisting frames are considered as being fully-rigid. Consequently, the real behavior of the connection, which has some level of flexibility, is ignored. This may result in inaccurate predictions of structural response. This study investigates the influence of flexibility of the extended end-plate connections in the steel moment frames. This is done at two levels. First, the actual microbehavior of extended end-plate moment connections is explored with re...
Barasz, Kate; John, Leslie K; Keenan, Elizabeth A; Norton, Michael I
2017-10-01
Pseudo-set framing-arbitrarily grouping items or tasks together as part of an apparent "set"-motivates people to reach perceived completion points. Pseudo-set framing changes gambling choices (Study 1), effort (Studies 2 and 3), giving behavior (Field Data and Study 4), and purchase decisions (Study 5). These effects persist in the absence of any reward, when a cost must be incurred, and after participants are explicitly informed of the arbitrariness of the set. Drawing on Gestalt psychology, we develop a conceptual account that predicts what will-and will not-act as a pseudo-set, and defines the psychological process through which these pseudo-sets affect behavior: over and above typical reference points, pseudo-set framing alters perceptions of (in)completeness, making intermediate progress seem less complete. In turn, these feelings of incompleteness motivate people to persist until the pseudo-set has been fulfilled. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Multiscale multiphysics and multidomain models—Flexibility and rigidity
International Nuclear Information System (INIS)
Xia, Kelin; Opron, Kristopher; Wei, Guo-Wei
2013-01-01
The emerging complexity of large macromolecules has led to challenges in their full scale theoretical description and computer simulation. Multiscale multiphysics and multidomain models have been introduced to reduce the number of degrees of freedom while maintaining modeling accuracy and achieving computational efficiency. A total energy functional is constructed to put energies for polar and nonpolar solvation, chemical potential, fluid flow, molecular mechanics, and elastic dynamics on an equal footing. The variational principle is utilized to derive coupled governing equations for the above mentioned multiphysical descriptions. Among these governing equations is the Poisson-Boltzmann equation which describes continuum electrostatics with atomic charges. The present work introduces the theory of continuum elasticity with atomic rigidity (CEWAR). The essence of CEWAR is to formulate the shear modulus as a continuous function of atomic rigidity. As a result, the dynamics complexity of a macromolecular system is separated from its static complexity so that the more time-consuming dynamics is handled with continuum elasticity theory, while the less time-consuming static analysis is pursued with atomic approaches. We propose a simple method, flexibility-rigidity index (FRI), to analyze macromolecular flexibility and rigidity in atomic detail. The construction of FRI relies on the fundamental assumption that protein functions, such as flexibility, rigidity, and energy, are entirely determined by the structure of the protein and its environment, although the structure is in turn determined by all the interactions. As such, the FRI measures the topological connectivity of protein atoms or residues and characterizes the geometric compactness of the protein structure. As a consequence, the FRI does not resort to the interaction Hamiltonian and bypasses matrix diagonalization, which underpins most other flexibility analysis methods. FRI's computational complexity is of O
Rigidity loss in disordered network materials
Ellenbroek, Wouter G.; Hagh, Varda F.; Kumar, Avishek; Thorpe, M. F.; van Hecke, Martin
Weakly jammed sphere packings show a very peculiar elasticity, with a ratio of compression modulus to shear modulus that diverges as the number of contacts approaches the minimum required for rigidity. Creating artificial isotropic network materials with this property is a challenge: so far, the least elaborate way to generate them is to actually simulate weakly compressed repulsive spheres. The next steps in designing such networks hinge upon a solid understanding of what properties of the sphere-packing derived network are essential for its elasticity. We elucidate the topological aspects of this question by comparing the rigidity transition in these networks to that in other random spring network models, including the common bond-diluted triangular net and a self-stress-free variant of that. We use the pebble game algorithm for identifying rigid clusters in mechanical networks to demonstrate that the marginally rigid state in sphere packings is perfectly isostatic everywhere, and the addition or removal of a single bond creates a globally stressed or globally floppy network, respectively. By contrast, the other classes of random network random networks show a more localized response to addition and removal of bonds, and, correspondingly, a more gradual rigidity transition.
21 CFR 876.3630 - Penile rigidity implant.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Penile rigidity implant. 876.3630 Section 876.3630...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Prosthetic Devices § 876.3630 Penile rigidity implant. (a) Identification. A penile rigidity implant is a device that consists of a pair of semi-rigid rods implanted in the...
serialising languages: satellite-framed, verb-framed or neither
African Journals Online (AJOL)
George Saad
Ghana Journal of Linguistics 2.1: 19-38 (2013). 19. SERIALISING LANGUAGES: SATELLITE-FRAMED, VERB-FRAMED OR NEITHER. Felix K. Ameka and James Essegbey. Abstract. The diversity in the coding of the core schema of motion, i.e., Path, has led to a traditional typology of languages into verb-framed and ...
Algorithms for Graph Rigidity and Scene Analysis
DEFF Research Database (Denmark)
Berg, Alex Rune; Jordán, Tibor
2003-01-01
We investigate algorithmic questions and structural problems concerning graph families defined by `edge-counts'. Motivated by recent developments in the unique realization problem of graphs, we give an efficient algorithm to compute the rigid, redundantly rigid, M-connected, and globally rigid...... components of a graph. Our algorithm is based on (and also extends and simplifies) the idea of Hendrickson and Jacobs, as it uses orientations as the main algorithmic tool. We also consider families of bipartite graphs which occur in parallel drawings and scene analysis. We verify a conjecture of Whiteley...... by showing that 2d-connected bipartite graphs are d-tight. We give a new algorithm for finding a maximal d-sharp subgraph. We also answer a question of Imai and show that finding a maximum size d-sharp subgraph is NP-hard....
Quantum mechanics of a generalised rigid body
International Nuclear Information System (INIS)
Gripaios, Ben; Sutherland, Dave
2016-01-01
We consider the quantum version of Arnold’s generalisation of a rigid body in classical mechanics. Thus, we quantise the motion on an arbitrary Lie group manifold of a particle whose classical trajectories correspond to the geodesics of any one-sided-invariant metric. We show how the derivation of the spectrum of energy eigenstates can be simplified by making use of automorphisms of the Lie algebra and (for groups of type I) by methods of harmonic analysis. We show how the method can be extended to cosets, generalising the linear rigid rotor. As examples, we consider all connected and simply connected Lie groups up to dimension 3. This includes the universal cover of the archetypical rigid body, along with a number of new exactly solvable models. We also discuss a possible application to the topical problem of quantising a perfect fluid. (paper)
Durable bistable auxetics made of rigid solids
Shang, Xiao; Liu, Lu; Rafsanjani, Ahmad; Pasini, Damiano
2018-02-01
Bistable Auxetic Metamaterials (BAMs) are a class of monolithic perforated periodic structures with negative Poisson's ratio. Under tension, a BAM can expand and reach a second state of equilibrium through a globally large shape transformation that is ensured by the flexibility of its elastomeric base material. However, if made from a rigid polymer, or metal, BAM ceases to function due to the inevitable rupture of its ligaments. The goal of this work is to extend the unique functionality of the original kirigami architecture of BAM to a rigid solid base material. We use experiments and numerical simulations to assess performance, bistability and durability of rigid BAMs at 10,000 cycles. Geometric maps are presented to elucidate the role of the main descriptors of BAM architecture. The proposed design enables the realization of BAM from a large palette of materials, including elastic-perfectly plastic materials and potentially brittle materials.
Torsional rigidity of submanifolds with controlled geometry
DEFF Research Database (Denmark)
Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente
2009-01-01
We prove explicit upper and lower bounds for the torsional rigidity of extrinsic domains of submanifolds ^m$ with controlled radial mean curvature in ambient Riemannian manifolds ^n$ with a pole $ and with sectional curvatures bounded from above and from below, respectively. These bounds are given...... in terms of the torsional rigidities of corresponding Schwarz symmetrizations of the domains in warped product model spaces. Our main results are obtained using methods from previously established isoperimetric inequalities, as found in e.g. [MP4] and [MP5]. As in [MP4] we also characterize the geometry...... of those situations in which the bounds for the torsional rigidity are actually attained and study the behavior at infinity of the so-called geometric average of the mean exit time for Brownian motion....
Conformal frame dependence of inflation
International Nuclear Information System (INIS)
Domènech, Guillem; Sasaki, Misao
2015-01-01
Physical equivalence between different conformal frames in scalar-tensor theory of gravity is a known fact. However, assuming that matter minimally couples to the metric of a particular frame, which we call the matter Jordan frame, the matter point of view of the universe may vary from frame to frame. Thus, there is a clear distinction between gravitational sector (curvature and scalar field) and matter sector. In this paper, focusing on a simple power-law inflation model in the Einstein frame, two examples are considered; a super-inflationary and a bouncing universe Jordan frames. Then we consider a spectator curvaton minimally coupled to a Jordan frame, and compute its contribution to the curvature perturbation power spectrum. In these specific examples, we find a blue tilt at short scales for the super-inflationary case, and a blue tilt at large scales for the bouncing case
... URL of this page: https://medlineplus.gov/faq/framing.html I'd like to link to MedlinePlus, ... M. encyclopedia. Our license agreements do not permit framing of their content from our site. For more ...
Type number and rigidity of fibred surfaces
International Nuclear Information System (INIS)
Markov, P E
2001-01-01
Infinitesimal l-th order bendings, 1≤l≤∞, of higher-dimensional surfaces are considered in higher-dimensional flat spaces (for l=∞ an infinitesimal bending is assumed to be an analytic bending). In terms of the Allendoerfer type number, criteria are established for the (r,l)-rigidity (in the terminology of Sabitov) of such surfaces. In particular, an (r,l)-infinitesimal analogue is proved of the classical theorem of Allendoerfer on the unbendability of surfaces with type number ≥3 and the class of (r,l)-rigid fibred surfaces is distinguished
Financial Constraints and Nominal Price Rigidities
DEFF Research Database (Denmark)
Menno, Dominik Francesco; Balleer, Almut; Hristov, Nikolay
that these empirical patterns are consistent with a partial equilibrium menu-cost model with a working capital constraint. We then use the model to show how the presence of financial frictions changes profits and the price distribution of firms compared to a model without financial frictions. Our results suggest...... that tighter financial constraints are associated with higher nominal rigidities, higher prices and lower output. Moreover, in response to aggregate shocks, aggregate price rigidity moves substantially, the response of inflation is dampened, while output reacts more in the presence of financial frictions...
Rigid origami vertices: conditions and forcing sets
Directory of Open Access Journals (Sweden)
Zachary Abel
2016-04-01
Full Text Available We develop an intrinsic necessary and sufficient condition for single-vertex origami crease patterns to be able to fold rigidly. We classify such patterns in the case where the creases are pre-assigned to be mountains and valleys as well as in the unassigned case. We also illustrate the utility of this result by applying it to the new concept of minimal forcing sets for rigid origami models, which are the smallest collection of creases that, when folded, will force all the other creases to fold in a prescribed way.
The PgaFrame - a frame for parallel genetic algorithms
Petit Silvestre, Jordi
1997-01-01
The PgaFrame offers to non-expert users the possibility to solve optimization problems via genetic algorithms on parallel computers. This frame has appeared as the natural fusion of two different projects: PgaPack and Frames. The PgaFrame combines the major features of these projects: it integrates the capabilities to specify genetic algorithms offered by the PgaPack library and the support of Frames to the easy and portable programming of parallel machines. In this way, a complex fra...
Energy Technology Data Exchange (ETDEWEB)
Sanfilippo, Antonio P.; McGrath, Liam R.; Whitney, Paul D.
2011-11-17
We present a computational approach to radical rhetoric that leverages the co-expression of rhetoric and action features in discourse to identify violent intent. The approach combines text mining and machine learning techniques with insights from Frame Analysis and theories that explain the emergence of violence in terms of moral disengagement, the violation of sacred values and social isolation in order to build computational models that identify messages from terrorist sources and estimate their proximity to an attack. We discuss a specific application of this approach to a body of documents from and about radical and terrorist groups in the Middle East and present the results achieved.
Reference frame for Product Configuration
DEFF Research Database (Denmark)
Ladeby, Klaes Rohde; Oddsson, Gudmundur Valur
2011-01-01
This paper presents a reference frame for configuration. The reference frame is established by review of existing literature, and consequently it is a theoretical frame of reference. The review of literature shows a deterioration of the understanding of configuration. Most recent literature reports...
New avenues for framing research
de Vreese, C.H.
2012-01-01
In this article, the author reviews the studies in this special issue of the American Behavioral Scientist. It is a strong collection of articles reporting findings from an integrated project that looks at frame building, frames, and effects of frames. The project is part of an exciting large-scale
An approximate method for lateral stability analysis of wall-frame ...
Indian Academy of Sciences (India)
Example 2. The frame structure with two spans eleven storeys in figure 4 has been considered for Example 2. The section properties of columns and heights of the storeys are given in table 4. All girders have the same cross section, and the modulus of elasticity of the structure is E = 25000 MN/m2. The equivalent rigidities of ...
effects of joints stiffening on the dynamic response of frames subje
African Journals Online (AJOL)
Uncle Greg 4 Real
Mechanics Technika, Sofia, 1988. 11. Ekere, J.T., Determination of. Stiffness for Timonshenko Beam-. Columns with Infinitely Rigid Ends and Their Application in the Analysis of Frames, M.Eng.(Struct. Engr). Project, UNN, 1988. 12. Diaz de Cossio,. Development of. Design Criteria for Reinforced concrete Box Culverts, Civil.
Directory of Open Access Journals (Sweden)
Bradley C. Freeman
2017-01-01
Full Text Available As economies in Southeast Asia develop, there is renewed interest in the impact such growth has on nature. This study seeks to investigate how environmental issues have been covered in the English-language press of the region. Are some countries providing greater print news coverage versus others? Are there detectable patterns or noticeable biases in the coverage? What sources are relied upon in the print media stories? And what frames do we see in the coverage? This study identified general coverage patterns of the environment over a 10-year period (2002-2012, in several of the region’s English-language newspapers. News stories were analyzed to discern the nature of the coverage, coding for several variables as indicated by previous literature. Results indicate that use of the term climate change became preferred over that of global warming. In addition, coverage increased greatly starting in 2006. Government officials were most often the sources quoted within stories (Claims. Articles contained more “judgments” about the issue than “solutions” (Frames. Finally, though most articles eschewed mentioning a specific actor as causing climate change, “man” was implicated in a number of stories more often than simply “nature” (Blame.
International Nuclear Information System (INIS)
Arunasalam, V.
1989-05-01
World space mapping in inertial frames is used to examine the Lorentz covariance of symmetry operations. It is found that the Galilean invariant concepts of simultaneity (S), parity (P), and time reversal symmetry (T) are not Lorentz covariant concepts for inertial observers. That is, just as the concept of simultaneity has no significance independent of the Lorentz inertial frame, likewise so are the concepts of parity and time reversal. However, the world parity (W) [i.e., the space-time reversal symmetry (P-T)] is a truly Lorentz covariant concept. Indeed, it is shown that only those mapping matrices M that commute with the Lorentz transformation matrix L (i.e., [M,L] = 0) are the ones that correspond to manifestly Lorentz covariant operations. This result is in accordance with the spirit of the world space Mach's principle. Since the Lorentz transformation is an orthogonal transformation while the Galilean transformation is not an orthogonal transformation, the formal relativistic space-time mapping theory used here does not have a corresponding non-relativistic counterpart. 12 refs
Identifying issue frames in text.
Directory of Open Access Journals (Sweden)
Eyal Sagi
Full Text Available Framing, the effect of context on cognitive processes, is a prominent topic of research in psychology and public opinion research. Research on framing has traditionally relied on controlled experiments and manually annotated document collections. In this paper we present a method that allows for quantifying the relative strengths of competing linguistic frames based on corpus analysis. This method requires little human intervention and can therefore be efficiently applied to large bodies of text. We demonstrate its effectiveness by tracking changes in the framing of terror over time and comparing the framing of abortion by Democrats and Republicans in the U.S.
Cracking of open traffic rigid pavement
Directory of Open Access Journals (Sweden)
Niken Chatarina
2017-01-01
Full Text Available The research is done by observing the growth of real structure cracking in Natar, Lampung, Indonesia compared to C. Niken’s et al research and literature study. The rigid pavement was done with open traffic system. There are two main crack types on Natar rigid pavement: cracks cross the road, and cracks spreads on rigid pavement surface. The observation of cracks was analyzed by analyzing material, casting, curing, loading and shrinkage mechanism. The relationship between these analysis and shrinkage mechanism was studied in concrete micro structure. Open traffic make hydration process occur under vibration; therefore, fresh concrete was compressed and tensioned alternately since beginning. High temperature together with compression, cement dissociation, the growth of Ca2+ at very early age leads abnormal swelling. No prevention from outside water movement leads hydration process occur with limited water which caused spreads fine cracks. Limited water improves shrinkage and plastic phase becomes shorter; therefore, rigid pavement can’t accommodate the abnormal swelling and shrinking alternately and creates the spread of cracks. Discontinuing casting the concrete makes both mix under different condition, the first is shrink and the second is swell and creates weak line on the border; so, the cracks appear as cracks across the road.
Geometric integrators for stochastic rigid body dynamics
Tretyakov, Mikhail
2016-01-05
Geometric integrators play an important role in simulating dynamical systems on long time intervals with high accuracy. We will illustrate geometric integration ideas within the stochastic context, mostly on examples of stochastic thermostats for rigid body dynamics. The talk will be mainly based on joint recent work with Rusland Davidchak and Tom Ouldridge.
Rigid pricing and rationally inattentive consumer
Czech Academy of Sciences Publication Activity Database
Matějka, Filip
2010-01-01
Roč. 20, č. 2 (2010), s. 1-40 ISSN 1211-3298 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : rational inattention * nominal rigidity Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp409.pdf
About deformation and rigidity in relativity
International Nuclear Information System (INIS)
Coll, Bartolome
2007-01-01
The notion of deformation involves that of rigidity. In relativity, starting from Born's early definition of rigidity, some other ones have been proposed, offering more or less interesting aspects but also accompanied of undesired or even pathological properties. In order to clarify the origin of these difficulties presented by the notion of rigidity in relativity, we analyze with some detail significant aspects of the unambiguous classical, Newtonian, notion. In particular, the relative character of its kinetic definition is pointed out, allowing to predict and to understand the limitations imposed by Herglotz-Noether theorem. Also, its equivalent dynamic definition is obtained and, in contrast, its absolute character is shown. But in spite of this absolute character, the dynamic definition is shown to be not extensible to relativity. The metric deformation of Minkowski space by the presence of a gravitational field is interpreted as a universal deformation, and it is shown that, under natural conditions, only a simple deformation law is possible, relating locally, but in an one-to-one way, gravitational fields and gauge classes of two-forms. We argue that fields of unit vectors associated to the internal gauge class of two-forms of every space-time (and, in particular, of Minkowski space-time) are the relativistic analogues of the classical accelerated observers, i.e. of the classical rigid motions. Some other consequences of the universal law of gravitational deformation are commented
Amortizing 3D Graphics Optimization Across Multiple Frames
National Research Council Canada - National Science Library
Durbin, Jim; Gossweiler, Rich; Pausch, Randy
1995-01-01
.... Well-known techniques such as transforming hierarchical geometry into a flat list and removing redundant graphics primitives are often performed off-line on static databases, or continuously every rendering frame...
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
with the attitudes of readers and customers. The data for the analysis consist of newspaper articles from the Danish broadsheet press in the period of October 2008 to November 2009 as well as communication material from the Bank’s website. References Charteris-Black, Jonathan. 2004. Corpus Approaches to Critical....... Professional Discourse. London/NY: Continuum. Hallahan, Kirk. 1999. Seven models of framing: Implications for public relations. Journal of Public Relations Research 11 (3): 205-242. Kövecses, Zoltán. 1986. Metaphors of Anger, Pride and Love. Amsterdam: John Benjamins. Kövecses, Zoltán. 2006. Language, Mind...... how conservatives use language to dominate politics. UC Berkeley News, October 23 2003. Available at http://berkeley.edu/news/media/releases/2003/10/27_lakoff.shtml Lakoff, George and Mark Johnson. [1980] 2003. Metaphors We Live By. Chicago: The University of Chicago Press....
DEFF Research Database (Denmark)
Petersen, Nils Holger
2010-01-01
. In Black Angels the composer – among other well-known pieces of music – quotes the medieval dies irae sequence and the second movement of Schubert’s string quartet in D minor (D. 810). The musical and intermedial references are framed with striking modernistic sounds exploring instrumental possibilities...... far beyond the traditional, thus creating a framework of extreme contrasts. The paper will contextualize, analyze and interpret Black Angels – which the composer explicitly linked to the Vietnam War – in a broad context of music, intermediality, religious symbolism, and cultural memory, pointing......The purpose of this article is to discuss Crumb’s musical and intermedial intertextuality mainly through his Black Angels: Thirteen Images from the Dark Land for Electric String Quartet (1970), as an individually original but also representative compositional practice for the twentieth century...
Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames
Directory of Open Access Journals (Sweden)
Kamanli Mehmet
2017-01-01
Full Text Available After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased.
Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames
Kamanli, Mehmet; Unal, Alptug
2017-10-01
After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased.
Riesz frames and approximation of the frame coefficients
DEFF Research Database (Denmark)
Casazza, P.; Christensen, Ole
1998-01-01
A frame is a fmaily {f i } i=1 ∞ of elements in a Hilbert space with the property that every element in can be written as a (infinite) linear combination of the frame elements. Frame theory describes how one can choose the corresponding coefficients, which are called frame coefficients. From...... the mathematical point of view this is gratifying, but for applications it is a problem that the calculation requires inversion of an operator on . The projection method is introduced in order to avoid this problem. The basic idea is to consider finite subfamilies {f i } i=1 n of the frame and the orthogonal...... projection Pn onto its span. For has a representation as a linear combination of fi, i=1,2,..., n and the corresponding coefficients can be calculated using finite dimensional methods. We find conditions implying that those coefficients converge to the correct frame coefficients as n→∞, in which case we have...
Biomechanical behavior of the tibiofibular frame in nonunion.
Gunzburg, R; Boulvin, S; Bourgeois, R; Wagner, J
1991-01-01
In this paper an in vitro investigation of the biomechanical behavior of the tibiofibular frame in nonunion using electrical extensometry is presented. The intact and untreated nonunited frames are studied as well as three surgical treatments classically used in nonunion: the plating technique, the onlay graft technique and the external fixation according to Ilizarov. The monopodal position with extended knee is considered, and particular attention is paid to the different muscle insertions. The results for the plating and onlay grafting techniques resemble those for the intact frame, whereas the Ilizarov external fixator increases the overall rigidity of the frame. In the untreated nonunited tibiofibular frame, an inversion of the tension and compression areas at the level of the tibia was found. We hypothesize that this phenomenon could be one of the mechanical factors leading to nonunion. Indeed, cyclic stresses in the fracture callus might prevent bony fusion, for the areas healing under compression stresses must become tension areas once the tibia is healed and vice versa.
The two-body problem of a pseudo-rigid body and a rigid sphere
DEFF Research Database (Denmark)
Kristiansen, Kristian Uldall; Vereshchagin, M.; Gózdziewski, K.
2012-01-01
n this paper we consider the two-body problem of a spherical pseudo-rigid body and a rigid sphere. Due to the rotational and "re-labelling" symmetries, the system is shown to possess conservation of angular momentum and circulation. We follow a reduction procedure similar to that undertaken...... in the study of the two-body problem of a rigid body and a sphere so that the computed reduced non-canonical Hamiltonian takes a similar form. We then consider relative equilibria and show that the notions of locally central and planar equilibria coincide. Finally, we show that Riemann's theorem on pseudo......-rigid bodies has an extension to this system for planar relative equilibria....
Fusion frames and G-frames in Banach spaces
Indian Academy of Sciences (India)
Amir Khosravi and Behrooz Khosravi. DEFINITION 1.2. Let X be a Banach space with dual space X. ∗ and Xd be a BK-space. A countable family. {gi } in X. ∗ is called an Xd-frame ... In §2 we study g-frames in Banach spaces and in §3 we study fusion frames in Banach spaces. ..... Soc., Providence, RI) (1999). [4] Casazza ...
Analytical Study of Common Rigid Steel Connections under the Effect of Heat
Directory of Open Access Journals (Sweden)
Rohola Rahnavard
2014-01-01
Full Text Available One of the most important members of steel structure’s connection region is beam-to-column connection. Rigid connection in steel moment frame has special role in the behavior of these structures and the fire resistance of these connections can be important. In this paper the behaviors of three common types of rigid connections in Iran under the effect of heat were studied by the use of numerical finite element methods through ABAQUS software. The models were verified by the use of an experimental model through elastic and plastic amplitudes up to collapse and during numerical results, and the effect of large deformation in the nonlinear region has also been considered. The results show that the connection with the end plate had a better performance against heat than other connections. Also reduced stiffness and lateral buckling in this connection were less than other connections.
Lectures on formal and rigid geometry
Bosch, Siegfried
2014-01-01
A first version of this work appeared in 2005 as a Preprint of the Collaborative Research Center "Geometrical Structures in Mathematics" at the University of Münster. Its aim was to offer a concise and self-contained 'lecture-style' introduction to the theory of classical rigid geometry established by John Tate, together with the formal algebraic geometry approach launched by Michel Raynaud. These Lectures are now viewed commonly as an ideal means of learning advanced rigid geometry, regardless of the reader's level of background. Despite its parsimonious style, the presentation illustrates a number of key facts even more extensively than any other previous work. This Lecture Notes Volume is a revised and slightly expanded version of the original preprint and has been published at the suggestion of several experts in the field.
Financial Constraints and Nominal Price Rigidities
DEFF Research Database (Denmark)
Menno, Dominik Francesco; Balleer, Almut; Hristov, Nikolay
This paper investigates how financial market imperfections and the frequency of price adjustment interact. Based on new firm-level evidence for Germany, we document that financially constrained firms adjust prices more often than their unconstrained counterparts, both upwards and downwards. We show...... that these empirical patterns are consistent with a partial equilibrium menu-cost model with a working capital constraint. We then use the model to show how the presence of financial frictions changes profits and the price distribution of firms compared to a model without financial frictions. Our results suggest...... that tighter financial constraints are associated with higher nominal rigidities, higher prices and lower output. Moreover, in response to aggregate shocks, aggregate price rigidity moves substantially, the response of inflation is dampened, while output reacts more in the presence of financial frictions...
Rigidity of the magic pentagram game
Kalev, Amir; Miller, Carl A.
2018-01-01
A game is rigid if a near-optimal score guarantees, under the sole assumption of the validity of quantum mechanics, that the players are using an approximately unique quantum strategy. Rigidity has a vital role in quantum cryptography as it permits a strictly classical user to trust behavior in the quantum realm. This property can be traced back as far as 1998 (Mayers and Yao) and has been proved for multiple classes of games. In this paper we prove ridigity for the magic pentagram game, a simple binary constraint satisfaction game involving two players, five clauses and ten variables. We show that all near-optimal strategies for the pentagram game are approximately equivalent to a unique strategy involving real Pauli measurements on three maximally-entangled qubit pairs.
[Abdominal pain in progressive encephalomyelitis with rigidity].
Seguier, J; Serratrice, J; Lachaud, A; Belenotti, P; Benyamine, A; Verschueren, A; Boucraut, J; Attarian, S; Weiller, P-J
2015-04-01
Stiff-person syndrome is rare neurological disease, associating trunk rigidity and painful muscular spasms. A clinical variant of stiff person syndrome is the progressive encephalomyelitis with rigidity and myoclonus (PERM), which includes neurological cognitive disturbances. We report a 73-year-old woman initially addressed for abdominal pain, anorexia and severe weight-loss, for whom diagnosis of PERM was made. Because of its various clinical presentations, sometimes without evidence for neurological disease, the diagnosis of PERM is delayed. The presence of antineuropile antibodies associated with muscular spasms at electromyogram are strong evidence for this diagnosis. Copyright © 2014 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.
Progressive encephalomyelitis with rigidity and myoclonus
Turner, M.R.; Irani, S.R.; Leite, M.I.; Nithi, K.; Vincent, A.
2011-01-01
Background: The syndrome of progressive encephalopathy with limb rigidity has been historically termed progressive encephalomyelitis with rigidity and myoclonus (PERM) or stiff-person syndrome plus. Methods: The case is presented of a previously healthy 28-year-old man with a rapidly fatal form of PERM developing over 2 months. Results: Serum antibodies to both NMDA receptors (NMDAR) and glycine receptors (GlyR) were detected postmortem, and examination of the brain confirmed an autoimmune encephalomyelitis, with particular involvement of hippocampal pyramidal and cerebellar Purkinje cells and relative sparing of the neocortex. No evidence for an underlying systemic neoplasm was found. Conclusion: This case displayed not only the clinical features of PERM, previously associated with GlyR antibodies, but also some of the features associated with NMDAR antibodies. This unusual combination of antibodies may be responsible for the particularly progressive course and sudden death. PMID:21775733
Progressive Encephalomyelitis With Rigidity: A Case Report
Baraba, Ranka; Jušić, Anica; Sruk, Ana
2010-01-01
Background/Objective: The most prominent clinical features of progressive encephalomyelitis with rigidity (PER) are painful spasms and rigidity accompanied by clinical signs of brainstem and spinal cord involvement. In initial reports, PER had fatal outcome. Later, clinical improvement related to corticosteroid therapy has been described in some cases. The objective of this study was to signify a reputed clinical significance of corticosteroid therapy in PER. Methods: Case report. Results: A 50-year-old man developed progressive syndrome of tonic extensor spasms. Magnetic resonance imaging (MRI) showed areas of signal changes in cervical spinal cord and lower brainstem, whereas cerebrospinal fluid analysis indicated subacute encephalomyelitis. His condition dramatically improved on oral corticosteroid therapy. Clinical improvement was accompanied by normalization of MRI findings. Conclusion: For this patient with PER, corticosteroid therapy was a dramatically effective and life-saving treatment, although initiated rather late in the course of the disease. PMID:20397447
On the Dynamics of Rigid Manipulators
International Nuclear Information System (INIS)
Hamdan, H.; Nuseirat, A.
2001-01-01
In this paper , the dynamics of rigid robot manipulators are investigated using Selective Modal Analysis (SMA). The method allows the determination of quantitative measures of the degree of the participation of the state variables in the system modes.Using Singular Value Decomposition (SVD) of appropriate matrices, we get useful information about the controllability and the observability of the manipulator. Numerical examples to illustrate the developed methods are presented. (authors) . 20 refs.,3 figs., 5 tabs
Investment Price Rigidities and Business Cycles
Moura, Alban
2015-01-01
I incorporate investment price rigidity in a two-sector monetary model of business cycles. Fit to quarterly U.S. time series, the model suggests that price sluggishness in the investment sector is the single most empirically relevant friction to match the data. Sticky investment prices constitute an important propagation mechanism to understand the sources of aggregate fluctuations, the dynamic effects of technology shocks, and the properties of the relative price of investment goods.
Frames, agency and institutional change
DEFF Research Database (Denmark)
Rasmussen, Grane Mikael Gregaard; Jensen, Per Langaa; Gottlieb, Stefan Christoffer
2017-01-01
This study examines change and the sources influencing the formulation and diffusion of policies in construction. The change examined is the introduction of a benchmarking policy initiative in the Danish construction industry. Using institutional theory with emphasis on the concepts of frames...... and framings, we show how strategically motivated actors are able to frame policy problems in ways that disclose the mixture of motives, interests and institutional mechanisms at play in change processes. In doing so, we contribute to the literature on the role of agency in institutional change and the framing...
DEFF Research Database (Denmark)
Christensen, Ole; Goh, Say Song
2012-01-01
The time–frequency analysis of a signal is often performed via a series expansion arising from well-localized building blocks. Typically, the building blocks are based on frames having either Gabor or wavelet structure. In order to calculate the coefficients in the series expansion, a dual frame...... is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients...
Analysis of the Behaviour of Semi Rigid Steel End Plate Connections
Directory of Open Access Journals (Sweden)
Bahaz A.
2018-01-01
Full Text Available The analysis of steel-framed building structures with full strength beam to column joints is quite standard nowadays. Buildings utilizing such framing systems are widely used in design practice. However, there is a growing recognition of significant benefits in designing joints as partial strength/semi-rigid. The design of joints within this partial strength/semi-rigid approach is becoming more and more popular. This requires the knowledge of the full nonlinear moment-rotation behaviour of the joint, which is also a design parameter. The rotational behaviour of steel semi rigid connections can be studied using the finite element method for the following three reasons: i such models are inexpensive; ii they allow the understanding of local effects, which are difficult to measure accurately physically, and iii they can be used to generate extensive parametric studies. This paper presents a three-dimensional finite element model using ABAQUS software in order to identify the effect of different parameters on the behaviour of semi rigid steel beam to column end plate connections. Contact and sliding between different elements, bolt pretension and geometric and material non-linearity are included in this model. A parametric study is conducted using a model of two end-plate configurations: flush and extended end plates. The studied parameters were as follows: bolts type, end plate thickness and column web stiffener. Then, the model was calibrated and validated with experimental results taken from the literature and with the model proposed by Eurocode3. The procedure for determining the moment–rotation curve using finite element analysis is also given together with a brief explanation of how the design moment resistance and the initial rotational stiffness of the joint are obtained.
Rigid geometry of curves and their Jacobians
Lütkebohmert, Werner
2016-01-01
This book presents some of the most important aspects of rigid geometry, namely its applications to the study of smooth algebraic curves, of their Jacobians, and of abelian varieties - all of them defined over a complete non-archimedean valued field. The text starts with a survey of the foundation of rigid geometry, and then focuses on a detailed treatment of the applications. In the case of curves with split rational reduction there is a complete analogue to the fascinating theory of Riemann surfaces. In the case of proper smooth group varieties the uniformization and the construction of abelian varieties are treated in detail. Rigid geometry was established by John Tate and was enriched by a formal algebraic approach launched by Michel Raynaud. It has proved as a means to illustrate the geometric ideas behind the abstract methods of formal algebraic geometry as used by Mumford and Faltings. This book should be of great use to students wishing to enter this field, as well as those already working in it.
Power to the frame: bringing sociology back to frame analysis
Vliegenthart, R.; van Zoonen, L.
2011-01-01
This article critically reviews current frame and framing research in media and communication studies. It is first argued that most authors fail to distinguish between ‘frame’ and ‘framing’ and therewith produce a conceptual confusion and imprecision that is not conducive to the field. Second, it is
Value Framing: A Prelude to Software Problem Framing
Wieringa, Roelf J.; Gordijn, Jaap; van Eck, Pascal; Cox, K.; Hall, J.G.; Rapanotti, L.
2004-01-01
Software problem framing is a way to find specifications for software. Software problem frames can be used to structure the environment of a software system (the machine) and specify desired software properties in such a way that we can show that software with these properties will help achieve the
New characterizations of fusion frames (frames of subspaces)
Indian Academy of Sciences (India)
Theory (College Park, MD, 2003) Contemp. Math. 345, Amer. Math. Soc. (RI: Provi- dence) (2004) 87–113. [4] Casazza P G and Kutyniok G, Robustness of Fusion Frames under Erasures of sub- spaces and of Local Frame Vectors, Radon transforms, geometry, and wavelets (LA: New Orleans) (2006) Contemp. Math., Amer.
Interactive streaming of stored multiview video using redundant frame structures.
Cheung, Gene; Ortega, Antonio; Cheung, Ngai-Man
2011-03-01
While much of multiview video coding focuses on the rate-distortion performance of compressing all frames of all views for storage or non-interactive video delivery over networks, we address the problem of designing a frame structure to enable interactive multiview streaming, where clients can interactively switch views during video playback. Thus, as a client is playing back successive frames (in time) for a given view, it can send a request to the server to switch to a different view while continuing uninterrupted temporal playback. Noting that standard tools for random access (i.e., I-frame insertion) can be bandwidth-inefficient for this application, we propose a redundant representation of I-, P-, and "merge" frames, where each original picture can be encoded into multiple versions, appropriately trading off expected transmission rate with storage, to facilitate view switching. We first present ad hoc frame structures with good performance when the view-switching probabilities are either very large or very small. We then present optimization algorithms that generate more general frame structures with better overall performance for the general case. We show in our experiments that we can generate redundant frame structures offering a range of tradeoff points between transmission and storage, e.g., outperforming simple I-frame insertion structures by up to 45% in terms of bandwidth efficiency at twice the storage cost.
Jet Ventilation during Rigid Bronchoscopy in Adults: A Focused Review
Directory of Open Access Journals (Sweden)
Laurie Putz
2016-01-01
Full Text Available The indications for rigid bronchoscopy for interventional pulmonology have increased and include stent placements and transbronchial cryobiopsy procedures. The shared airway between anesthesiologist and pulmonologist and the open airway system, requiring specific ventilation techniques such as jet ventilation, need a good understanding of the procedure to reduce potentially harmful complications. Appropriate adjustment of the ventilator settings including pause pressure and peak inspiratory pressure reduces the risk of barotrauma. High frequency jet ventilation allows adequate oxygenation and carbon dioxide removal even in cases of tracheal stenosis up to frequencies of around 150 min−1; however, in an in vivo animal model, high frequency jet ventilation along with normal frequency jet ventilation (superimposed high frequency jet ventilation has been shown to improve oxygenation by increasing lung volume and carbon dioxide removal by increasing tidal volume across a large spectrum of frequencies without increasing barotrauma. General anesthesia with a continuous, intravenous, short-acting agent is safe and effective during rigid bronchoscopy procedures.
Echternach, Matthias; Dippold, Sebastian; Richter, Bernhard
2016-01-01
Vocal fold oscillation patterns in tenors singing at high pitches (stage voice above the passaggio) are not yet understood in detail. Nine professional opera tenors performed a transition from modal register (220 Hz) to falsetto or stage voice above the passaggio (440 Hz) on an /i/ vowel. High-speed digital imaging was performed using a rigid laryngoscopic system with a frame rate of 4,000 frames per second. During the transition to stage voice above the passaggio seven out of nine tenors exhibited a strong retraction of the epiglottis with rising F0, which prevented further analysis of vocal fold oscillations. During transitions to falsetto many supraglottic modifications were also observed. Tenor stage voice above the passaggio seems to be typically associated with retraction of the epiglottis for the vowel /i/ thus preventing examination of vocal fold oscillations using rigid laryngoscopy.
A Cognitive Developmental Model of Rigidity in Senescence.
Lapsley, Daniel K.; Enright, Robert D.
1983-01-01
The rigidity construct is reinterpreted in terms of the cognitive developmental approach. A review reveals both cognitive and developmental themes, with an emphasis on the structural and operational properties of rigidity. Notes weaknesses of previous approaches to rigidity and discusses implications and predictions from the proposed model.…
Directory of Open Access Journals (Sweden)
Yakhlef O.
2017-06-01
Full Text Available A fixed point algorithmis proposed to solve a fluid-structure interaction problem with the supplementary constraint that the structure displacements are limited by a rigid obstacle. Fictitious domain approach with penalization is used for the fluid equations. The surface forces from the fluid acting on the structure are computed using the fluid solution in the structure domain. The continuity of the fluid and structure velocities is imposed through the penalization parameter. The constraint of non-penetration of the elastic structure into the rigid obstacle is treated weakly. A convex constrained optimization problem is solved in order to get the structure displacements. Numerical results are presented.
FRAME CATAGORIZATION OF CONVERSATIONAL INTIMACY
Lyubov Kit
2017-01-01
The article deals with the notion of intimacy. The frame of intimacy is studied on the basis of the linguistic parameters, analysis of text extracts and universal knowledge about intimacy. Frame analysis helped to establish the catagorization of types and nominators of intimate speech genres, their construction in static and dynamic aspects.
Frame Catagorization of Conversational Intimacy
Lyubov Kit
2017-01-01
The article deals with the notion of intimacy. The frame of intimacy is studied on the basis of the linguistic parameters, analysis of text extracts and universal knowledge about intimacy. Frame analysis helped to establish the catagorization of types and nominators of intimate speech genres, their construction in static and dynamic aspects.
Kruml, David
2010-12-01
Skew frames represent a common generalization of frames and orthomodular lattices. They could serve as Lindenbaum algebras of quantum intuitionistic logic as well as invariants of noncommutative C*-algebras. It is shown that lattices of open projections with skew (partial) operations are complete invariants of C*-algebras and that these operations are preserved by morphims of C*-algebras.
Influence of flock coating on bending rigidity of woven fabrics
Ozdemir, O.; Kesimci, M. O.
2017-10-01
This work presents the preliminary results of our efforts that focused on the effect of the flock coating on the bending rigidity of woven fabrics. For this objective, a laboratory scale flocking unit is designed and flocked samples of controlled flock density are produced. Bending rigidity of the samples with different flock densities are measured on both flocked and unflocked sides. It is shown that the bending rigidity depends on both flock density and whether the side to be measured is flocked or not. Adhesive layer thickness on the bending rigidity is shown to be dramatic. And at higher basis weights, flock density gets less effective on bending rigidity.
Rigid-only versus combined rigid and flexible percutaneous nephrolithotomy (PNL)
DEFF Research Database (Denmark)
Cracco, Cecilia M; Knoll, Thomas; Liatsikos, Evangelos N
2017-01-01
INTRODUCTION: Percutaneous nephrolithotomy (PNL) is usually performed worldwide with a rigid-only antegrade approach. Daily practice suggests that adding flexible nephroscopy and/or ureteroscopy to conventional rigid PNL might improve its efficacy and safety, but available evidence is weak....... Appraisal of reliable outcomes of such PNL techniques would better guide intraoperative choices and optimize surgical results. Therefore our objective was to systematically review relevant literature comparing the outcomes of rigid-only PNL and combined flexible PNLs (adding flexible nephroscopy and....../or flexible ureteroscopy) for the treatment of large and/or complex upper urinary tract calculi, with regard to efficacy and safety. EVIDENCE ACQUISITION: Ovid MedLine (R), PubMed, Scopus and Web of Science databases were searched in August 2016 to identify relevant studies. Article selection was performed...
Clinical effects of using rigid gas permeable contact lens for refractoriness amblyopia
Directory of Open Access Journals (Sweden)
Xiao-Yan Li
2014-07-01
Full Text Available AIM:To explore the clinical effects of using rigid gas permeable contact lens(RGPfor refractoriness amblyopia patients. METHODS: Ninety-eight cases(98 eyeswere voluntarily divided into RGP group and frame glasses group, and the two groups were received the regularity combined training to treat amblyopia for 6mo. We overviewed the corrected vision(on that day, 1, 3, 6moand the complication in RGP group. RESULTS: The corrected vision in RGP group was obviously better than that in control group during the same time. The therapeutic efficacy in RGP group was better than that in frame glasses group, without serious complications at 6mo after treatment.CONCLUSION: RGP groups could get better corrected visual acuity. It is safe and effective to improve corrected vision for refractoriness amblyopia patients.
Brownian dynamics of confined rigid bodies
Energy Technology Data Exchange (ETDEWEB)
Delong, Steven; Balboa Usabiaga, Florencio; Donev, Aleksandar, E-mail: donev@courant.nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)
2015-10-14
We introduce numerical methods for simulating the diffusive motion of rigid bodies of arbitrary shape immersed in a viscous fluid. We parameterize the orientation of the bodies using normalized quaternions, which are numerically robust, space efficient, and easy to accumulate. We construct a system of overdamped Langevin equations in the quaternion representation that accounts for hydrodynamic effects, preserves the unit-norm constraint on the quaternion, and is time reversible with respect to the Gibbs-Boltzmann distribution at equilibrium. We introduce two schemes for temporal integration of the overdamped Langevin equations of motion, one based on the Fixman midpoint method and the other based on a random finite difference approach, both of which ensure that the correct stochastic drift term is captured in a computationally efficient way. We study several examples of rigid colloidal particles diffusing near a no-slip boundary and demonstrate the importance of the choice of tracking point on the measured translational mean square displacement (MSD). We examine the average short-time as well as the long-time quasi-two-dimensional diffusion coefficient of a rigid particle sedimented near a bottom wall due to gravity. For several particle shapes, we find a choice of tracking point that makes the MSD essentially linear with time, allowing us to estimate the long-time diffusion coefficient efficiently using a Monte Carlo method. However, in general, such a special choice of tracking point does not exist, and numerical techniques for simulating long trajectories, such as the ones we introduce here, are necessary to study diffusion on long time scales.
Grasping rigid objects in zero-g
Anderson, Greg D.
1993-12-01
The extra vehicular activity helper/retriever (EVAHR) is a prototype for an autonomous free- flying robotic astronaut helper. The ability to grasp a moving object is a fundamental skill required for any autonomous free-flyer. This paper discusses an algorithm that couples resolved acceleration control with potential field based obstacle avoidance to enable a manipulator to track and capture a rigid object in (imperfect) zero-g while avoiding joint limits, singular configurations, and unintentional impacts between the manipulator and the environment.
Rigid gas permeable lenses and patient management.
Terry, R; Schnider, C; Holden, B A
1989-01-01
The introduction of new rigid gas permeable (RGP) contact lens materials provides the practitioner with a number of alternatives for patient management. But whatever the lens materials used, problems related to the lenses, care and maintenance solutions, and patients may arise. This paper examines concerns such as parameter instability, durability of lenses, compatibility of materials and solutions, patient education and compliance, 3 and 9 o'clock staining, corneal distortion, and lid changes. Suggestions are made on ways to avoid or minimize problems related to RGP lens wear.
Mechanical Characterization of Rigid Polyurethane Foams
Energy Technology Data Exchange (ETDEWEB)
Lu, Wei-Yang [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Mechanics of Materials
2014-12-01
Foam materials are used to protect sensitive components from impact loading. In order to predict and simulate the foam performance under various loading conditions, a validated foam model is needed and the mechanical properties of foams need to be characterized. Uniaxial compression and tension tests were conducted for different densities of foams under various temperatures and loading rates. Crush stress, tensile strength, and elastic modulus were obtained. A newly developed confined compression experiment provided data for investigating the foam flow direction. A biaxial tension experiment was also developed to explore the damage surface of a rigid polyurethane foam.
A rigid porous filter and filtration method
Energy Technology Data Exchange (ETDEWEB)
Chiang, Ta-Kuan; Straub, Douglas, Straub L.; Dennis, Richard A.
1998-12-01
The present invention involves a porous rigid filter comprising a plurality of concentric filtration elements having internal flow passages and forming external flow passages there between. The present invention also involves a pressure vessel containing the filter for the removal of particulate from high pressure particulate containing gases, and further involves a method for using the filter to remove such particulate. The present filter has the advantage of requiring fewer filter elements due to the high surface area- to-volume ratio provided by the filter, requires a reduced pressure vessel size, and exhibits enhanced mechanical design properties, improved cleaning properties, configuration options, modularity and ease of fabrication.
Serialising languages: Satellite-framed, verb-framed or neither ...
African Journals Online (AJOL)
The diversity in the coding of the core schema of motion, i.e., Path, has led to a traditional typology of languages into verb-framed and satellite-framed languages. In the former Path is encoded in verbs and in the latter it is encoded in non-verb elements that function as sisters to co-event expressing verbs such as manner ...
Framing of health information messages.
Akl, Elie A; Oxman, Andrew D; Herrin, Jeph; Vist, Gunn E; Terrenato, Irene; Sperati, Francesca; Costiniuk, Cecilia; Blank, Diana; Schünemann, Holger
2011-12-07
The same information about the evidence on health effects can be framed either in positive words or in negative words. Some research suggests that positive versus negative framing can lead to different decisions, a phenomenon described as the framing effect. Attribute framing is the positive versus negative description of a specific attribute of a single item or a state, for example, "the chance of survival with cancer is 2/3" versus "the chance of mortality with cancer is 1/3". Goal framing is the description of the consequences of performing or not performing an act as a gain versus a loss, for example, "if you undergo a screening test for cancer, your survival will be prolonged" versus "if you don't undergo screening test for cancer, your survival will be shortened". To evaluate the effects of attribute (positive versus negative) framing and of goal (gain versus loss) framing of the same health information, on understanding, perception of effectiveness, persuasiveness, and behavior of health professionals, policy makers, and consumers. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, issue 3 2007), MEDLINE (Ovid) (1966 to October 2007), EMBASE (Ovid) (1980 to October 2007), PsycINFO (Ovid) (1887 to October 2007). There were no language restrictions. We reviewed the reference lists of related systematic reviews, included studies and of excluded but closely related studies. We also contacted experts in the field. We included randomized controlled trials, quasi-randomised controlled trials, and cross-over studies with health professionals, policy makers, and consumers evaluating one of the two types of framing. Two review authors extracted data in duplicate and independently. We graded the quality of evidence for each outcome using the GRADE approach. We standardized the outcome effects using standardized mean difference (SMD). We stratified the analysis by the type of framing (attribute, goal) and conducted pre
Social costs of natural gas market rigidities
Energy Technology Data Exchange (ETDEWEB)
Broadman, H.G.; Darmstadter, J.; Montgomery, W.D.
1983-01-01
To the extent that there are market imperfections and other constraints limiting consumption of gas to levels significantly below those dictated by underlying economic factors of cost and producibility, society bears the cost resulting from misallocation of resources and avoidable environmental deterioration. Given the regulatory and institutional setting within which the natural gas industry has been forced to operate, there is a strong presumption that such inhibitions on gas use may in fact exist. Some rigidities stem undoubtedly from characteristics unique to gas as a natural-resource commodity. This report presents a framework for reviewing potential sources of constraints, rigidities, and distortions in the functioning of natural gas markets under the Natural Gas Policy Act of 1978 (NGPA) and other legislation. The organizing principle and primary focus of the paper are the sequence of transactions between wellhead and point of consumption, with major attention to industrial and power plant use. The transactions in question are between: producers and pipelines; pipelines and distributors; distributors and end users; and pipelines and industrial end users (mainline sales). In addition to these vertical transactions, there are horizontal transactions between pipelines (off-system sales) and between distributors. 22 references, 1 figure, 1 table.
Optimized imaging using non-rigid registration
International Nuclear Information System (INIS)
Berkels, Benjamin; Binev, Peter; Blom, Douglas A.; Dahmen, Wolfgang; Sharpley, Robert C.; Vogt, Thomas
2014-01-01
The extraordinary improvements of modern imaging devices offer access to data with unprecedented information content. However, widely used image processing methodologies fall far short of exploiting the full breadth of information offered by numerous types of scanning probe, optical, and electron microscopies. In many applications, it is necessary to keep measurement intensities below a desired threshold. We propose a methodology for extracting an increased level of information by processing a series of data sets suffering, in particular, from high degree of spatial uncertainty caused by complex multiscale motion during the acquisition process. An important role is played by a non-rigid pixel-wise registration method that can cope with low signal-to-noise ratios. This is accompanied by formulating objective quality measures which replace human intervention and visual inspection in the processing chain. Scanning transmission electron microscopy of siliceous zeolite material exhibits the above-mentioned obstructions and therefore serves as orientation and a test of our procedures. - Highlights: • Developed a new process for extracting more information from a series of STEM images. • An objective non-rigid registration process copes with distortions. • Images of zeolite Y show retrieval of all information available from the data set. • Quantitative measures of registration quality were implemented. • Applicable to any serially acquired data, e.g. STM, AFM, STXM, etc
Vertebral Column Resection for Rigid Spinal Deformity.
Saifi, Comron; Laratta, Joseph L; Petridis, Petros; Shillingford, Jamal N; Lehman, Ronald A; Lenke, Lawrence G
2017-05-01
Broad narrative review. To review the evolution, operative technique, outcomes, and complications associated with posterior vertebral column resection. A literature review of posterior vertebral column resection was performed. The authors' surgical technique is outlined in detail. The authors' experience and the literature regarding vertebral column resection are discussed at length. Treatment of severe, rigid coronal and/or sagittal malalignment with posterior vertebral column resection results in approximately 50-70% correction depending on the type of deformity. Surgical site infection rates range from 2.9% to 9.7%. Transient and permanent neurologic injury rates range from 0% to 13.8% and 0% to 6.3%, respectively. Although there are significant variations in EBL throughout the literature, it can be minimized by utilizing tranexamic acid intraoperatively. The ability to correct a rigid deformity in the spine relies on osteotomies. Each osteotomy is associated with a particular magnitude of correction at a single level. Posterior vertebral column resection is the most powerful posterior osteotomy method providing a successful correction of fixed complex deformities. Despite meticulous surgical technique and precision, this robust osteotomy technique can be associated with significant morbidity even in the most experienced hands.
Frames and counter-frames giving meaning to dementia: a framing analysis of media content.
Van Gorp, Baldwin; Vercruysse, Tom
2012-04-01
Media tend to reinforce the stigmatization of dementia as one of the most dreaded diseases in western society, which may have repercussions on the quality of life of those with the illness. The persons with dementia, but also those around them become imbued with the idea that life comes to an end as soon as the diagnosis is pronounced. The aim of this paper is to understand the dominant images related to dementia by means of an inductive framing analysis. The sample is composed of newspaper articles from six Belgian newspapers (2008-2010) and a convenience sample of popular images of the condition in movies, documentaries, literature and health care communications. The results demonstrate that the most dominant frame postulates that a human being is composed of two distinct parts: a material body and an immaterial mind. If this frame is used, the person with dementia ends up with no identity, which is in opposition to the Western ideals of personal self-fulfilment and individualism. For each dominant frame an alternative counter-frame is defined. It is concluded that the relative absence of counter-frames confirms the negative image of dementia. The inventory might be a help for caregivers and other professionals who want to evaluate their communication strategy. It is discussed that a more resolute use of counter-frames in communication about dementia might mitigate the stigma that surrounds dementia. Copyright © 2012 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Valerie Jean O’Keeffe
2015-06-01
Full Text Available Current patient safety policy focuses nursing on patient care goals, often overriding nurses’ safety. Without understanding how nurses construct work health and safety (WHS, patient and nurse safety cannot be reconciled. Using ethnography, we examine social contexts of safety, studying 72 nurses across five Australian hospitals making decisions during patient encounters. In enacting safe practice, nurses used “frames” built from their contextual experiences to guide their behavior. Frames are produced by nurses, and they structure how nurses make sense of their work. Using thematic analysis, we identify four frames that inform nurses’ decisions about WHS: (a communicating builds knowledge, (b experiencing situations guides decisions, (c adapting procedures streamlines work, and (d team working promotes safe working. Nurses’ frames question current policy and practice by challenging how nurses’ safety is positioned relative to patient safety. Recognizing these frames can assist the design and implementation of effective WHS management.
Vertical bending strength and torsional rigidity analysis of formula student car chassis
Hazimi, Hashfi; Ubaidillah, Setiyawan, Adi Eka Putra; Ramdhani, Hanief Cahya; Saputra, Murnanda Zaesy; Imaduddin, Fitrian
2018-02-01
Formula Society of Automotive Engineers (FSAE) is a competition for students to construct formula student car. One of an essential part of a formula student car is its chassis. Chassis is an internal vehicle frame which holds all another part of the vehicle and secures the driver. The team have to design their chassis and tests their design to achieve the best chassis that fulfill the regulation. This paper contains chassis design from Bengawan FSAE Team and some FEA tests to find out the Tensile Strength, Torsional Rigidity, and Von Misses Stress of Formula SAE car. Torsional rigidity was found by applying the static torsional test. The results from torsional rigidity test are a maximum deformation of 9.9512 mm with 1.7064 safety factor, and 35.935 MPa maximum Von Misses Stress. Moreover, then the result of the vertical bending strength test is 8.1214 mm max deformation with safety factor 4.2717, and 29.226 MPa maximum Von Misses Stress.
Numerical algorithm for rigid body position estimation using the quaternion approach
Zigic, Miodrag; Grahovac, Nenad
2017-11-01
This paper deals with rigid body attitude estimation on the basis of the data obtained from an inertial measurement unit mounted on the body. The aim of this work is to present the numerical algorithm, which can be easily applied to the wide class of problems concerning rigid body positioning, arising in aerospace and marine engineering, or in increasingly popular robotic systems and unmanned aerial vehicles. Following the considerations of kinematics of rigid bodies, the relations between accelerations of different points of the body are given. A rotation matrix is formed using the quaternion approach to avoid singularities. We present numerical procedures for determination of the absolute accelerations of the center of mass and of an arbitrary point of the body expressed in the inertial reference frame, as well as its attitude. An application of the algorithm to the example of a heavy symmetrical gyroscope is presented, where input data for the numerical procedure are obtained from the solution of differential equations of motion, instead of using sensor measurements.
DEFF Research Database (Denmark)
Lazarov, Boyan Stefanov; Ditlevsen, Ove
2005-01-01
The object of study is a stationary Gaussian white noise excited plane multistory shear frame with a large number of rigid traverses. All the traverse-connecting columns have finite symmetrical yield limits except the columns in one or more of the bottom floors. The columns behave linearly elasti...
Flexible body dynamics in a local frame with explicitly predicted motion
DEFF Research Database (Denmark)
Kawamoto, A.; Krenk, Steen; Suzuki, A.
2010-01-01
This paper deals with formulation of dynamics of a moving flexible body in a local frame of reference. In a conventional approach the local frame is normally fixed to the corresponding body and always represents the positions and angles of the body: the positions and angles are represented...... of motion extremely complicated. This is because the representation of the rotation of a body is highly non-linear and this non-linearity makes the coefficient matrices dependent on the coordinates themselves. In this paper, we propose an alternative way of treating the issue by explicitly predicting...... the body motions and regularly updating the local frame. First, the motion of the local frame is assumed to explicitly follow the associated moving body. Then, the equations of motion are derived in a set of generalized coordinates that express both rigid-body and elastic degrees of freedom in the local...
The design and analysis of the mechanical property test platform frame for marine structures
Directory of Open Access Journals (Sweden)
Wen-xian Tang
2016-01-01
Full Text Available In order to realize mechanical properties test of the emergency towing arrangements, anchor chain and other large marine components, a large-tonnage and multi-function horizontal tension test platform is put forward in this paper. The paper analyzes the disadvantages of the frame structure of the existing experimental platform and designs the composite structure of the concrete and steel. The steel has good elasticity and toughness, the concrete has good performance of high rigidity and compression resistance, so the composite structure takes the advantages of both. The sharp of the frame is like “L”, which can be used to testing different projects. The paper gives the detailed size and analysis procedure of the frame. And it finds a more reasonable structure by means of finite element to analyze and optimize. The frame structure has the advantages of low weight and cost. The platform has been installed in Zhoushan, China successfully.
Elastic image registration via rigid object motion induced deformation
Zheng, Xiaofen; Udupa, Jayaram K.; Hirsch, Bruce E.
2011-03-01
In this paper, we estimate the deformations induced on soft tissues by the rigid independent movements of hard objects and create an admixture of rigid and elastic adaptive image registration transformations. By automatically segmenting and independently estimating the movement of rigid objects in 3D images, we can maintain rigidity in bones and hard tissues while appropriately deforming soft tissues. We tested our algorithms on 20 pairs of 3D MRI datasets pertaining to a kinematic study of the flexibility of the ankle complex of normal feet as well as ankles affected by abnormalities in foot architecture and ligament injuries. The results show that elastic image registration via rigid object-induced deformation outperforms purely rigid and purely nonrigid approaches.
A characterization of tight and dual generalized translation invariant frames
DEFF Research Database (Denmark)
Jakobsen, Mads Sielemann; Lemvig, Jakob
2015-01-01
, for each j we let Γj, be a closed subgroup of G such that G/Γj is compact. A GTI system is then the collection of functions UjεJ{gj, p(· - γ}γεΓj, pεPj. Many well known systems, such as wavelet, shearlet and Gabor systems, both the discrete and continuous types, are GTI systems. We characterize when...... such systems form tight frames, and when two GTI Bessel systems form dual frames for L2(G). In particular, this offers a unified approach to the theory of discrete and continuous frames and, e.g., yields well known results for discrete and continuous Gabor and wavelet systems....
Consumption habits and interest rate rigidity
Directory of Open Access Journals (Sweden)
Wilfredo L. Maldonado
2011-09-01
Full Text Available In this paper we provide a micro model of loans which the lender is a monopolistic bank and the borrower is a competitive consumer with consumption habits who may default on part of his debt. In this setting, we prove that the loan demand curve is kinked and therefore it is possible to find interest rate rigidity in equilibrium as well as asymmetric response of loans to interest rate variations. Finally, we show through an example that the credit supply, as a function of the marginal cost of the bank, exhibits a discontinuity on that marginal cost. As a consequence, lowering the basic interest rate of the economy may produce a sudden increase in credit demand/supply and in the default on debts.
Modeling Decomposition of Unconfined Rigid Polyurethane Foam
Energy Technology Data Exchange (ETDEWEB)
CHU,TZE YAO; ERICKSON,KENNETH L.; HOBBS,MICHAEL L.
1999-11-01
The decomposition of unconfined rigid polyurethane foam has been modeled by a kinetic bond-breaking scheme describing degradation of a primary polymer and formation of a thermally stable secondary polymer. The bond-breaking scheme is resolved using percolation theory to describe evolving polymer fragments. The polymer fragments vaporize according to individual vapor pressures. Kinetic parameters for the model were obtained from Thermal Gravimetric Analysis (TGA). The chemical structure of the foam was determined from the preparation techniques and ingredients used to synthesize the foam. Scale-up effects were investigated by simulating the response of an incident heat flux of 25 W/cm{sup 2} on a partially confined 8.8-cm diameter by 15-cm long right circular cylinder of foam which contained an encapsulated component. Predictions of center, midradial, and component temperatures, as well as regression of the foam surface, were in agreement with measurements using thermocouples and X-ray imaging.
Modeling Decomposition of Unconfined Rigid Polyurethane Foam
Energy Technology Data Exchange (ETDEWEB)
HOBBS,MICHAEL L.; ERICKSON,KENNETH L.; CHU,TZE YAO
1999-11-08
The decomposition of unconfined rigid polyurethane foam has been modeled by a kinetic bond-breaking scheme describing degradation of a primary polymer and formation of a thermally stable secondary polymer. The bond-breaking scheme is resolved using percolation theory to describe evolving polymer fragments. The polymer fragments vaporize according to individual vapor pressures. Kinetic parameters for the model were obtained from Thermal Gravimetric Analysis (TGA). The chemical structure of the foam was determined from the preparation techniques and ingredients used to synthesize the foam. Scale-up effects were investigated by simulating the response of an incident heat flux of 25 W/cm{sup 2} on a partially confined 8.8-cm diameter by 15-cm long right circular cylinder of foam that contained an encapsulated component. Predictions of center, midradial, and component temperatures, as well as regression of the foam surface, were in agreement with measurements using thermocouples and X-ray imaging.
Field cracking performance of airfield rigid pavements
Directory of Open Access Journals (Sweden)
Yusuf Mehta
2017-08-01
Full Text Available This paper discusses cracking in airport pavements as studied in Construction Cycle 6 of testing carried out at the National Airport Pavement Testing Facility by the Federal Aviation Administration. Pavements of three different flexural strengths as well as two different subgrades, a soft bituminous layer and a more rigid layer known as econocrete, were tested. In addition to this, cracking near two types of isolated transition joints, a reinforced edge joint and a thickened edge joint, was considered. The pavement sections were tested using a moving load simulating that of an aircraft. It has been determined that the degree of cracking was reduced as the flexural strength of the pavement was increased and that fewer cracks formed over the econocrete base than over the bituminous base. In addition, the thickened edge transition joint was more effective in preventing cracking at the edges compared to the reinforced edge joint.
Observational properties of rigidly rotating dust configurations
Energy Technology Data Exchange (ETDEWEB)
Ilyas, Batyr; Malafarina, Daniele [Nazarbayev University, Department of Physics, Astana (Kazakhstan); Yang, Jinye [Fudan University, Center for Field Theory and Particle Physics and Department of Physics, Shanghai (China); Bambi, Cosimo [Fudan University, Center for Field Theory and Particle Physics and Department of Physics, Shanghai (China); Eberhard-Karls Universitaet Tuebingen, Theoretical Astrophysics, Tuebingen (Germany)
2017-07-15
We study the observational properties of a class of exact solutions of Einstein's field equations describing stationary, axially symmetric, rigidly rotating dust (i.e. non-interacting particles). We ask the question whether such solutions can describe astrophysical rotating dark matter clouds near the center of galaxies and we probe the possibility that they may constitute an alternative to supermassive black holes at the center of galaxies. We show that light emission from accretion disks made of ordinary baryonic matter in this space-time has several differences with respect to the emission of light from similar accretion disks around black holes. The shape of the iron Kα line in the reflection spectrum of accretion disks can potentially distinguish this class of solutions from the Kerr metric, but this may not be possible with current X-ray missions. (orig.)
Static friction between rigid fractal surfaces.
Alonso-Marroquin, Fernando; Huang, Pengyu; Hanaor, Dorian A H; Flores-Johnson, E A; Proust, Gwénaëlle; Gan, Yixiang; Shen, Luming
2015-09-01
Using spheropolygon-based simulations and contact slope analysis, we investigate the effects of surface topography and atomic scale friction on the macroscopically observed friction between rigid blocks with fractal surface structures. From our mathematical derivation, the angle of macroscopic friction is the result of the sum of the angle of atomic friction and the slope angle between the contact surfaces. The latter is obtained from the determination of all possible contact slopes between the two surface profiles through an alternative signature function. Our theory is validated through numerical simulations of spheropolygons with fractal Koch surfaces and is applied to the description of frictional properties of Weierstrass-Mandelbrot surfaces. The agreement between simulations and theory suggests that for interpreting macroscopic frictional behavior, the descriptors of surface morphology should be defined from the signature function rather than from the slopes of the contacting surfaces.
Management of rigid post-traumatic kyphosis.
Wu, S S; Hwa, S Y; Lin, L C; Pai, W M; Chen, P Q; Au, M K
1996-10-01
Rigid post-traumatic kyphosis after fracture of the thoracolumbar and lumbar spine represents a failure of initial management of the injury. Kyphosis moves the center of gravity anterior. The kyphosis and instability may result in pain, deformity, and increased neurologic deficits. Management for symptomatic post-traumatic kyphosis always has presented a challenge to orthopedic surgeons. To evaluate the surgical results of one stage posterior correction for rigid symptomatic post-traumatic kyphosis of the thoracolumbar and lumbar spine. The management for post-traumatic kyphosis remains controversial. Anterior, posterior, or combined anterior and posterior procedures have been advocated by different authors and show various degrees of success. One vertebra immediately above and below the level of the deformity was instrumented posteriorly by a transpedicular system (internal fixator AO). Posterior decompression was performed by excision of the spinal process and bilateral laminectomy. With the deformed vertebra through the pedicle, the vertebral body carefully is removed around the pedicle level, approximating a wedge shape. The extent to which the deformed vertebral body should be removed is determined by the attempted correction. Correction of the deformity is achieved by manipulation of the operating table and compression of the adjacent Schanz screws above and below the lesion. Thirteen patients with post-traumatic kyphosis with symptoms of fatigue and pain caused by slow progression of kyphotic deformities received posterior decompression, correction, and stabilization as a definitive treatment. The precorrection kyphosis ranged from 30-60 degrees, with a mean of 40 degrees +/- 10.8 degrees. After correction, kyphosis was reduced to an average of 1.5 degrees +/- 3.8 degrees, with a range from -5 degrees to 5 degrees. The average angle of correction was 38.8 degrees +/- 10.4 degrees, with a range from 25 degrees to 60 degrees. Significant difference was found
Rigid-only versus combined rigid and flexible percutaneous nephrolithotomy: a systematic review.
Cracco, Cecilia M; Knoll, Thomas; Liatsikos, Evangelos N; Osther, Palle J; Smith, Arthur D; Scarpa, Roberto M; Scoffone, Cesare M
2017-08-01
Percutaneous nephrolithotomy (PNL) is usually performed worldwide with a rigid-only antegrade approach. Daily practice suggests that adding flexible nephroscopy and/or ureteroscopy to conventional rigid PNL might improve its efficacy and safety, but available evidence is weak. Appraisal of reliable outcomes of such PNL techniques would better guide intraoperative choices and optimize surgical results. Therefore, our objective was to systematically review relevant literature comparing the outcomes of rigid-only PNL and combined flexible PNLs (adding flexible nephroscopy and/or flexible ureteroscopy) for the treatment of large and/or complex upper urinary tract calculi, with regard to efficacy and safety. Ovid MedLine, PubMed, Scopus and Web of Science databases were searched in August 2016 to identify relevant studies. Article selection was performed according to the Preferred Reporting Items for Systematic Review and Meta-analysis criteria. Six articles reporting on 666 patients were included: two randomized controlled trials, two retrospective comparative studies and two case series ≥50 patients (one prospective and one retrospective). A narrative synthesis of minor evidences was also prepared. The adjunct of flexible nephroscopy and/or ureteroscopy provided better stone-free rates (range 86.7-96.97%), through a single percutaneous access most of the times and in any position, reducing the need for second-look procedures. Safety of the combined flexible procedures was improved to a variable degree, with a consensual reduction of the mean hospital stay (range 5.1-7 days). The current evidence suggests that patients with large and/or complex urolithiasis might benefit from the adjunct of flexible nephroscopy and/or ureteroscopy to rigid PNL.
DEFF Research Database (Denmark)
Christensen, Ole; Lindner, Alexander M
2001-01-01
We give lower frame bounds for finite subfamilies of a frame of exponentials {e(i lambdak(.))}k is an element ofZ in L-2(-pi,pi). We also present a method for approximation of the inverse frame operator corresponding to {e(i lambdak(.))}k is an element ofZ, where knowledge of the frame bounds for...
Another frame, another game? : Explaining framing effects in economic games
Gerlach, Philipp; Jaeger, B.; Hopfensitz, A.; Lori, E.
2016-01-01
Small changes in the framing of games (i.e., the way in which the game situation is described to participants) can have large effects on players' choices. For example, referring to a prisoner's dilemma game as the "Community Game" as opposed to the "Wall Street Game" can double the cooperation rate
Rigidity and definition of Caribbean plate motion from COCONet and campaign GPS observations
Mattioli, G. S.; Miller, J. A.; DeMets, C.; Jansma, P. E.
2015-12-01
The kinematic model of the Caribbean plate presented by DeMets et al. (2007) is based on velocities from 6 continuous and 14 campaign GPS sites. COCONet is a multi-hazard GPS-Met observatory, which extends the existing infrastructure of the PBO in North America into the Caribbean basin. In 2010, UNAVCO in collaboration with UCAR, was funded by NSF to design, build, and initially maintain a network of 50 new cGPS/Met sites and include data from another 50 existing sites in the Caribbean region. The COCONet siting plan is for 46 new stations, 21 refurbished stations, and 77 existing stations across 26 nations in the Caribbean region. Data from all COCONet sites flow into the UNAVCO archive and are processed by the PBO analysis centers and are also processed independently by the UTA Geodesy Lab using GIPSY-OASISII (v.6.3) using an APP strategy and final, precise orbits, clocks, and EOP from JPL in the IGS08r frame. We present a refined estimate of Caribbean plate motion by evaluating data from an expanded number of stations with an improved spatial distribution. In order to better constrain the eastern margin of the plate near the Lesser Antilles subduction interface, campaign GPS observations have been collected on the island of Dominica over the last decade. These are combined with additional campaign observations from the western Caribbean, specifically from Honduras and Nicaragua. We have analyzed a total of 117 sites from the Caribbean region, including campaign data and the data from the cGPS stations that comprise COCONet. An updated velocity field for the Caribbean plate is presented and an inversion of the velocities for 24 sites yields a plate angular velocity that differs from previously published models. Our best fitting inversion to GPS velocities from these 24 sites suggests that 2-plate model for the Caribbean is required to fit the GPS observations, which implies that the Caribbean is undergoing modest (1-3 mm/yr) deformation within its interior. Some
Thermal stresses in an orthotropic rectangular plate with a rigid ribbonlike inclusion
International Nuclear Information System (INIS)
Sumi, N.
1981-01-01
On the basis of the complex variable method for determining the stationary two-dimensional thermal stresses, the thermal stresses in an orthotropic rectangular plate with a rigid ribbonlike inclusion under a steady state temperature field is considered. The solution is found by the analytic continuation argument and the modified mapping-collocation technique. Numerical results indicate a dependence of the orthotropic stress intensity factors on the thermal, elastic and geometrical constants over a certain parameter range. (orig.)
The rigid Horowitz-Myers conjecture
Energy Technology Data Exchange (ETDEWEB)
Woolgar, Eric [Dept. of Mathematical and Statistical Sciences andTheoretical Physics Institute, University of Alberta,Edmonton, AB, T6G 2G1 (Canada)
2017-03-20
The new positive energy conjecture was first formulated by Horowitz and Myers in the late 1990s to probe for a possible extended, nonsupersymmetric AdS/CFT correspondence. We consider a version formulated for complete, asymptotically Poincaré-Einstein Riemannian metrics (M,g) with bounded scalar curvature R≥−n(n−1) and with no (inner) boundary except possibly a finite union of compact, totally geodesic hypersurfaces (horizons). This version then asserts that any such (M,g) must have mass not less than a certain bound which is realized as the mass m{sub 0} of a metric g{sub 0} induced on a time-symmetric slice of a spacetime called an AdS soliton. This conjecture remains unproved, having so far resisted standard techniques. Little is known other than that the conjecture is true for metrics which are sufficiently small perturbations of g{sub 0}. We pose another test for the conjecture. We assume its validity and attempt to prove as a corollary the corresponding scalar curvature rigidity statement, which is that g{sub 0} is the unique asymptotically Poincaré-Einstein metric with mass m{sub 0} obeying R≥−n(n−1). Were a second such metric g{sub 1} not isometric to g{sub 0} to exist, it then may well admit perturbations of lower mass, contradicting the assumed validity of the conjecture. We find enough rigidity to show that the minimum mass metric must be static Einstein, so the problem is reduced to that of static uniqueness. When n=3 the manifold must be isometric to a time-symmetric slice of an AdS soliton spacetime, or must have a non-compact horizon. En route we study the mass aspect, obtaining and generalizing known results: (i) we relate the mass aspect of static metrics to the holographic energy density, (ii) we obtain the conformal invariance of the mass aspect when the bulk dimension is odd, and (iii) we show the vanishing of the mass aspect for negative Einstein manifolds with Einstein conformal boundary.
Reinforced molecular recognition as an alternative to rigid receptors
Otto, Sijbren
2006-01-01
In theory, a perfectly rigid receptor will probably be an unbeatable binder. However, rigidity may not be easy to achieve in practice and it is certainly not Nature’s method to realise high affinity. In many proteins binding affinity is increased through non-covalent interactions within the protein.
Non-rigid image registration using bone growth model
DEFF Research Database (Denmark)
Bro-Nielsen, Morten; Gramkow, Claus; Kreiborg, Sven
1997-01-01
Non-rigid registration has traditionally used physical models like elasticity and fluids. These models are very seldom valid models of the difference between the registered images. This paper presents a non-rigid registration algorithm, which uses a model of bone growth as a model of the change b...
Sparsity and spectral properties of dual frames
DEFF Research Database (Denmark)
Krahmer, Felix; Kutyniok, Gitta; Lemvig, Jakob
2013-01-01
We study sparsity and spectral properties of dual frames of a given finite frame. We show that any finite frame has a dual with no more than $n^2$ non-vanishing entries, where $n$ denotes the ambient dimension, and that for most frames no sparser dual is possible. Moreover, we derive an expressio...
2010-10-01
... 49 Transportation 5 2010-10-01 2010-10-01 false Frames. 393.201 Section 393.201 Transportation... SAFE OPERATION Frames, Cab and Body Components, Wheels, Steering, and Suspension Systems § 393.201 Frames. (a) The frame or chassis of each commercial motor vehicle shall not be cracked, loose, sagging or...
Key Frame Extraction in the Summary Space.
Li, Xuelong; Zhao, Bin; Lu, Xiaoqiang
2017-07-04
Key frame extraction is an efficient way to create the video summary which helps users obtain a quick comprehension of the video content. Generally, the key frames should be representative of the video content, meanwhile, diverse to reduce the redundancy. Based on the assumption that the video data are near a subspace of a high-dimensional space, a new approach, named as key frame extraction in the summary space, is proposed for key frame extraction in this paper. The proposed approach aims to find the representative frames of the video and filter out similar frames from the representative frame set. First of all, the video data are mapped to a high-dimensional space, named as summary space. Then, a new representation is learned for each frame by analyzing the intrinsic structure of the summary space. Specifically, the learned representation can reflect the representativeness of the frame, and is utilized to select representative frames. Next, the perceptual hash algorithm is employed to measure the similarity of representative frames. As a result, the key frame set is obtained after filtering out similar frames from the representative frame set. Finally, the video summary is constructed by assigning the key frames in temporal order. Additionally, the ground truth, created by filtering out similar frames from human-created summaries, is utilized to evaluate the quality of the video summary. Compared with several traditional approaches, the experimental results on 80 videos from two datasets indicate the superior performance of our approach.
The theory of pseudo-rigid bodies
Cohen, Harley
1988-01-01
This monograph concerns the development, analysis, and application of the theory of pseudo-rigid bodies. It collects together our work on that subject over the last five years. While some results have appeared else where, much of the work is new. Our objective in writing this mono graph has been to present a new theory of the deformation of bodies, one that has not only a firm theoretical basis, but also the simplicity to serve as an effective tool in practical problems. Consequently, the main body of the treatise is a multifaceted development of the theory, from foundations to explicit solutions to linearizations to methods of approximation. The fact that this variety of aspects, each examined in considerable detail, can be collected together in a single, unified treat ment gives this theory an elegance that we feel sets it apart from many others. While our goal has always been to give a complete treatment of the theory as it now stands, the work here is not meant to be definitive. Theories are not ent...
Almost Poisson integration of rigid body systems
International Nuclear Information System (INIS)
Austin, M.A.; Krishnaprasad, P.S.; Li-Sheng Wang
1993-01-01
In this paper we discuss the numerical integration of Lie-Poisson systems using the mid-point rule. Since such systems result from the reduction of hamiltonian systems with symmetry by lie group actions, we also present examples of reconstruction rules for the full dynamics. A primary motivation is to preserve in the integration process, various conserved quantities of the original dynamics. A main result of this paper is an O(h 3 ) error estimate for the Lie-Poisson structure, where h is the integration step-size. We note that Lie-Poisson systems appear naturally in many areas of physical science and engineering, including theoretical mechanics of fluids and plasmas, satellite dynamics, and polarization dynamics. In the present paper we consider a series of progressively complicated examples related to rigid body systems. We also consider a dissipative example associated to a Lie-Poisson system. The behavior of the mid-point rule and an associated reconstruction rule is numerically explored. 24 refs., 9 figs
Framing the future of fracking
Metze, Tamara
2017-01-01
Hydraulic fracturing is a technology developed to improve and increase the production of natural gas. In many countries, including the Netherlands, it has caused environmental controversies. In these controversies, 'futurity framing' may open up debates for alternative paradigms such as
Watson, Andrew B.
2012-01-01
To enhance the quality of the theatre experience, the film industry is interested in achieving higher frame rates for capture and display. In this talk I will describe the basic spatio-temporal sensitivities of human vision, and how they respond to the time sequence of static images that is fundamental to cinematic presentation.
Quantum strategies in moving frames
International Nuclear Information System (INIS)
Tan Jianchuan; Wang Anmin
2009-01-01
We investigate quantum strategies in moving frames by considering Prisoners' Dilemma and propose four thresholds of γ for two players to determine their Nash Equilibria. We find that the relativistic operations could enhance or diminish the quantum features of the game for different players who move in different directions relative to the arbiter
Media framing and social movements
Vliegenthart, R.; Snow, D.A.; Della Porta, D.; Klandermans, B.; McAdam, D.
2013-01-01
In their study of media content, mass communication scholars commonly rely on Entman's (1993: 52) definition of framing: "[selecting] some aspects of a perceived reality and make them more salient in a communicating text, in such a way as to promote a particular problem definition, causal
Quantum strategies in moving frames
Energy Technology Data Exchange (ETDEWEB)
Tan Jianchuan [Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China)], E-mail: tanjc@mail.ustc.edu.cn; Wang Anmin [Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China)], E-mail: anmwang@ustc.edu.cn
2009-02-16
We investigate quantum strategies in moving frames by considering Prisoners' Dilemma and propose four thresholds of {gamma} for two players to determine their Nash Equilibria. We find that the relativistic operations could enhance or diminish the quantum features of the game for different players who move in different directions relative to the arbiter.
G-frames with bounded linear operators
Xiao, Xiang-chun; Zhu, Yu-can; Shu, Zhi-biao; Ding, Ming-ling
2015-01-01
In this paper, we introduce the more general g-frame which is called a $K$-g-frame by combining a g-frame with a bounded linear operator $K$ in a Hilbert space. We give several equivalent characterizations for $K$-g-frames and discuss the stability of perturbation for $K$-g-frames. We also investigate the relationship between a $K$-g-frame and the range of the bounded linear operator $K$. In the end, we give two sufficient conditions for the remainder of a $K$-g-frame after an erasure to stil...
Framing and misperception in public good experiments
DEFF Research Database (Denmark)
Fosgaard, Toke Reinholt; Hansen, Lars Gårn; Wengström, Erik Roland
2017-01-01
Earlier studies have found that framing has substantial impact on the degree of cooperation observed in public good experiments. We show that the way the public good game is framed affects misperceptions about the incentives of the game. Moreover, we show that such framing-induced differences...... in misperceptions are linked to the framing effect on subjects' cooperation behavior. When we do not control for the different levels of misperceptions between frames, we observe a significant framing effect on subjects’ cooperation preferences. However, this framing effect becomes insignificant once we remove...
Frame covariant nonminimal multifield inflation
Directory of Open Access Journals (Sweden)
Sotirios Karamitsos
2018-02-01
Full Text Available We introduce a frame-covariant formalism for inflation of scalar-curvature theories by adopting a differential geometric approach which treats the scalar fields as coordinates living on a field-space manifold. This ensures that our description of inflation is both conformally and reparameterization covariant. Our formulation gives rise to extensions of the usual Hubble and potential slow-roll parameters to generalized fully frame-covariant forms, which allow us to provide manifestly frame-invariant predictions for cosmological observables, such as the tensor-to-scalar ratio r, the spectral indices nR and nT, their runnings αR and αT, the non-Gaussianity parameter fNL, and the isocurvature fraction βiso. We examine the role of the field space curvature in the generation and transfer of isocurvature modes, and we investigate the effect of boundary conditions for the scalar fields at the end of inflation on the observable inflationary quantities. We explore the stability of the trajectories with respect to the boundary conditions by using a suitable sensitivity parameter. To illustrate our approach, we first analyze a simple minimal two-field scenario before studying a more realistic nonminimal model inspired by Higgs inflation. We find that isocurvature effects are greatly enhanced in the latter scenario and must be taken into account for certain values in the parameter space such that the model is properly normalized to the observed scalar power spectrum PR. Finally, we outline how our frame-covariant approach may be extended beyond the tree-level approximation through the Vilkovisky–De Witt formalism, which we generalize to take into account conformal transformations, thereby leading to a fully frame-invariant effective action at the one-loop level.
Frame covariant nonminimal multifield inflation
Karamitsos, Sotirios; Pilaftsis, Apostolos
2018-02-01
We introduce a frame-covariant formalism for inflation of scalar-curvature theories by adopting a differential geometric approach which treats the scalar fields as coordinates living on a field-space manifold. This ensures that our description of inflation is both conformally and reparameterization covariant. Our formulation gives rise to extensions of the usual Hubble and potential slow-roll parameters to generalized fully frame-covariant forms, which allow us to provide manifestly frame-invariant predictions for cosmological observables, such as the tensor-to-scalar ratio r, the spectral indices nR and nT, their runnings αR and αT, the non-Gaussianity parameter fNL, and the isocurvature fraction βiso. We examine the role of the field space curvature in the generation and transfer of isocurvature modes, and we investigate the effect of boundary conditions for the scalar fields at the end of inflation on the observable inflationary quantities. We explore the stability of the trajectories with respect to the boundary conditions by using a suitable sensitivity parameter. To illustrate our approach, we first analyze a simple minimal two-field scenario before studying a more realistic nonminimal model inspired by Higgs inflation. We find that isocurvature effects are greatly enhanced in the latter scenario and must be taken into account for certain values in the parameter space such that the model is properly normalized to the observed scalar power spectrum PR. Finally, we outline how our frame-covariant approach may be extended beyond the tree-level approximation through the Vilkovisky-De Witt formalism, which we generalize to take into account conformal transformations, thereby leading to a fully frame-invariant effective action at the one-loop level.
Molecular rigidity and enthalpy-entropy compensation in DNA melting.
Vargas-Lara, Fernando; Starr, Francis W; Douglas, Jack F
2017-11-15
Enthalpy-entropy compensation (EEC) is observed in diverse molecular binding processes of importance to living systems and manufacturing applications, but this widely occurring phenomenon is not sufficiently understood from a molecular physics standpoint. To gain insight into this fundamental problem, we focus on the melting of double-stranded DNA (dsDNA) since measurements exhibiting EEC are extensive for nucleic acid complexes and existing coarse-grained models of DNA allow us to explore the influence of changes in molecular parameters on the energetic parameters by using molecular dynamics simulations. Previous experimental and computational studies have indicated a correlation between EEC and changes in molecular rigidity in certain binding-unbinding processes, and, correspondingly, we estimate measures of DNA molecular rigidity under a wide range of conditions, along with resultant changes in the enthalpy and entropy of binding. In particular, we consider variations in dsDNA rigidity that arise from changes of intrinsic molecular rigidity such as varying the associative interaction strength between the DNA bases, the length of the DNA chains, and the bending stiffness of the individual DNA chains. We also consider extrinsic changes of molecular rigidity arising from the addition of polymer additives and geometrical confinement of DNA between parallel plates. All our computations confirm EEC and indicate that this phenomenon is indeed highly correlated with changes in molecular rigidity. However, two distinct patterns relating to how DNA rigidity influences the entropy of association emerge from our analysis. Increasing the intrinsic DNA rigidity increases the entropy of binding, but increases in molecular rigidity from external constraints decreases the entropy of binding. EEC arises in numerous synthetic and biological binding processes and we suggest that changes in molecular rigidity might provide a common origin of this ubiquitous phenomenon in the mutual
Elasto-plastic frame under horizontal and vertical Gaussian excitation
DEFF Research Database (Denmark)
Ditlevsen, Ove Dalager; Tarp-Johansen, Niels Jacob; Randrup-Thomsen, S.
1999-01-01
Taking geometric non-linearity into account anoscillator of the form as aportal frame with a rigid traverse and with ideal-elastic ideal-plasticclamped-in columns behaves under horizontalexcitation as an ideal-elastic hardening / softening-plastic oscilator given that the columns carry atension....../compression axial force. Assuming that the horizontal excitationof the traverse is Gaussian white noise, statistics related to the plastic displacement response are determinedby use of simulation based on the Slepian modelprocess method combined with envelope excursion properties. Besidesgiving physical insight...... the method givesgood approximations to results obtained by slow direct simulation of thetotal response. Moreover, the influence of a randomly varying axial column force isinvestigated by direct response simulation. This case corresponds to parametric excitation as generated by the vertical acceleration...
Farzadkhoo, Maryam; Keshavarzi, Alireza; Hamidifar, Hossein; Javan, Mahmood
2018-03-26
Releasing and mixing of pollutants in rivers can cause serious threats for downstream users. Longitudinal dispersion is an important factor in describing pollutant transport process in rivers. The focus of this study is on the effect of floodplain rigid vegetation characteristics including its arrangement, density and relative depth (the ratio of the flow depth in the main channel to that over floodplain) on flow and longitudinal dispersion coefficient in a meandering channel with compound cross section. Digital image processing technique was used to measure the tracer concentration. Sequential images were continuously captured at seven sections downstream of release point. PVC cylinders were installed over the floodplain to simulate rigid vegetation in tandem and random arrangements. Acoustic Doppler Velocimeter (Micro-ADV) was used to measure 3-D velocity components. The results showed that roughening the flood plain with stems increases the longitudinal flow velocity and Reynolds shear stress in the main channel, while these parameters decrease in the flood plain compared to non-vegetated cases. As a result, in the presence of rigid vegetation, the travel time decreases in the main channel up to 20% compared to non-vegetated conditions. As the relative flow depth increases, the dimensionless longitudinal dispersion coefficient, K/U ∗ H, decreases up to 74%. Also, the dimensionless longitudinal dispersion coefficient increases up to 38% with stem density in a specific relative flow depth of D r = 0.11. Finally, a comparison has been made between laboratory data and some well-known previously reported models. Later, the most accurate equations are presented for predicting the longitudinal dispersion coefficient in rigid vegetated compound meandering channels. The results of the present study reveal that rigid vegetation over flood plain can be used as an alternative method in river rehabilitation projects for environmental management purposes. Copyright
Nanomanufacturing of continuous composite nanofibers with confiment-induced morphologies
Kamperman, M.M.G.; Korley, L.T.J.; Yau, B.; Johansen, K.M.; Joo, Y.L.; Wiesner, U.
2010-01-01
Continuous core-shell nanofibers with poly(isoprene-block-dimethylaminoethyl methacrylate) (PI-b-PDMAEMA) block copolymer/polymer derived ceramic (PDC) precursor nanocomposites as cores enveloped in rigid polyacrylonitrile (PAN) shells were nanomanufactured using coaxial electrospinning. The
Variance based OFDM frame synchronization
Directory of Open Access Journals (Sweden)
Z. Fedra
2012-04-01
Full Text Available The paper deals with a new frame synchronization scheme for OFDM systems and calculates the complexity of this scheme. The scheme is based on the computing of the detection window variance. The variance is computed in two delayed times, so a modified Early-Late loop is used for the frame position detection. The proposed algorithm deals with different variants of OFDM parameters including guard interval, cyclic prefix, and has good properties regarding the choice of the algorithm's parameters since the parameters may be chosen within a wide range without having a high influence on system performance. The verification of the proposed algorithm functionality has been performed on a development environment using universal software radio peripheral (USRP hardware.
Meta framing and polyphonic structures
DEFF Research Database (Denmark)
Pedersen, Karsten
2017-01-01
The present case study deals with the Danish tabloid BT’s coverage of Cycling team owner Bjarne Riis’s possible knowledge of doping use in his cycling teams. BT sees itself as a sports paper and tries to signal that it takes sports coverage as seriously other kinds of news. We see that reflected...... and mapping the entire news output in one specified week, and draws on insights from framing theory as well as polyphony theory....
Innovations in rocking wall-frame systems-theory and development
Grigorian, Mark; Tavousi, Shayan
2017-09-01
The need to improve the seismic performance of buildings has brought about innovative systems such as rocking wall-moment frame (RWMF) combinations. The behavior of RWMFs can best be visualized by the moment-frame (MF) restraining the wall in place, and the rigid rocking wall (RRW) providing additional damping and imposing uniform drift along the height of the frame. A novel method of analysis followed by the development of a new lateral resisting system is introduced. The proposed concepts lead to an efficient structural configuration with provisions for self-centering, reparability, performance control, damage tolerance and collapse prevention. Exact, unique, closed form formulae have been provided to assess the collapse prevention and self-centering capabilities of the system. The objective is to provide an informative account of RWMF behavior for preliminary design as well as educational purposes. All formulae have been verified by independent computer analysis. Parametric examples have been provided to verify the validity of the proposed solutions.
Predicting the Strength of Online News Frames
Directory of Open Access Journals (Sweden)
Hrvoje Jakopović
2017-10-01
Full Text Available Framing theory is one of the most significant approaches to understanding media and their potential impact on publics. Leaving aside that fact, the author finds that publicity effects seem to be dispersed and difficult to catch for public relations. This article employs a specific research design, which could be applied to public relations practice, namely with a view to observing correlations between specific media frames and individual frames. The approach is based on the typology of news frames. The author attributes negative, positive and neutral determinants to the types of frames in his empirical research. Online news regarding three transport organizations and the accompanying user comments (identified as negative, positive and neutral are analysed by means of the method of content and sentiment analysis. The author recognizes user comments and reviews as individual frames that take part in the creation of online image. Furthermore, he identifies the types of media frames as well as individual frames manifested as image, and undertakes correlation research in order to establish their prediction potential. The results expose the most frequently used types of media frames concerning the transport domain. The media are keen to report through the attribution of responsibility frame, and after that, through the economic frame and the conflict frame, but, on the other hand, they tend to neglect the human interest frame and the morality frame. The results show that specific types of news frames enable better prediction of user reactions. The economic frame and the human interest frame therefore represent the most predictable types of frame.
Friction effects on lateral loading behavior of rigid piles
DEFF Research Database (Denmark)
Zania, Varvara; Hededal, Ole
2012-01-01
The adequacy of the p -y curves used in the current practice for the design of rigid pile foundations with large diameter, like in the case of monopile foundations of offshore wind turbines, has been widely questioned. The current study aims at analyzing the lateral behavior of rigid piles, while...... the lateral capacity of the pile. The obtained p - y curves demonstrate the importance of the aforementioned parameters in the design of rigid piles, as the reduction of friction along the interface reduces not only the ultimate load but also the stiffness of the soil-pile response. Read More: http...
Observations on the partial breaking of N=2 rigid supersymmetry
Directory of Open Access Journals (Sweden)
Laura Andrianopoli
2015-05-01
Full Text Available We study the partial breaking of N=2 rigid supersymmetry for a generic rigid special geometry of n abelian vector multiplets in the presence of Fayet–Iliopoulos terms induced by the hyper-Kähler momentum map. By exhibiting the symplectic structure of the problem we give invariant conditions for the breaking to occur, which rely on a quartic invariant of the Fayet–Iliopoulos charges as well as on a modification of the N=2 rigid symmetry algebra by a vector central charge.
Observations on the Partial Breaking of $N=2$ Rigid Supersymmetry
Andrianopoli, Laura; Ferrara, Sergio; Trigiante, Mario
2015-01-01
We study the partial breaking of $N=2$ rigid supersymmetry for a generic rigid special geometry of $n$ abelian vector multiplets in the presence of Fayet-Iliopoulos terms induced by the Hyper-K\\"ahler momentum map. By exhibiting the symplectic structure of the problem we give invariant conditions for the breaking to occur, which rely on a quartic invariant of the Fayet-Iliopoulos charges as well as on a modification of the $N=2$ rigid symmetry algebra by a vector central charge.
Soft-rigid interaction mechanism towards a lobster-inspired hybrid actuator
Chen, Yaohui; Wan, Fang; Wu, Tong; Song, Chaoyang
2018-01-01
Soft pneumatic actuators (SPAs) are intrinsically light-weight, compliant and therefore ideal to directly interact with humans and be implemented into wearable robotic devices. However, they also pose new challenges in describing and sensing their continuous deformation. In this paper, we propose a hybrid actuator design with bio-inspirations from the lobsters, which can generate reconfigurable bending movements through the internal soft chamber interacting with the external rigid shells. This design with joint and link structures enables us to exactly track its bending configurations that previously posed a significant challenge to soft robots. Analytic models are developed to illustrate the soft-rigid interaction mechanism with experimental validation. A robotic glove using hybrid actuators to assist grasping is assembled to illustrate their potentials in safe human-robot interactions. Considering all the design merits, our work presents a practical approach to the design of next-generation robots capable of achieving both good accuracy and compliance.
Work flow of signal processing data of ground penetrating radar case of rigid pavement measurements
Handayani, Gunawan
2015-04-01
The signal processing of Ground Penetrating Radar (GPR) requires a certain work flow to obtain good results. Even though the Ground Penetrating Radar data looks similar with seismic reflection data, but the GPR data has particular signatures that the seismic reflection data does not have. This is something to do with coupling between antennae and the ground surface. Because of this, the GPR data should be treated differently from the seismic signal data processing work flow. Even though most of the processing steps still follow the same work flow of seismic reflection data such as: filtering, predictive deconvolution etc. This paper presents the work flow of GPR processing data on rigid pavement measurements. The processing steps start from raw data, de-Wow process, remove DC and continue with the standard process to get rid of noises i.e. filtering process. Some radargram particular features of rigid pavement along with pile foundations are presented.
Work flow of signal processing data of ground penetrating radar case of rigid pavement measurements
Energy Technology Data Exchange (ETDEWEB)
Handayani, Gunawan [The Earth Physics and Complex Systems Research Group (Jl. Ganesa 10 Bandung Indonesia) gunawanhandayani@gmail.com (Indonesia)
2015-04-16
The signal processing of Ground Penetrating Radar (GPR) requires a certain work flow to obtain good results. Even though the Ground Penetrating Radar data looks similar with seismic reflection data, but the GPR data has particular signatures that the seismic reflection data does not have. This is something to do with coupling between antennae and the ground surface. Because of this, the GPR data should be treated differently from the seismic signal data processing work flow. Even though most of the processing steps still follow the same work flow of seismic reflection data such as: filtering, predictive deconvolution etc. This paper presents the work flow of GPR processing data on rigid pavement measurements. The processing steps start from raw data, de-Wow process, remove DC and continue with the standard process to get rid of noises i.e. filtering process. Some radargram particular features of rigid pavement along with pile foundations are presented.
Work flow of signal processing data of ground penetrating radar case of rigid pavement measurements
International Nuclear Information System (INIS)
Handayani, Gunawan
2015-01-01
The signal processing of Ground Penetrating Radar (GPR) requires a certain work flow to obtain good results. Even though the Ground Penetrating Radar data looks similar with seismic reflection data, but the GPR data has particular signatures that the seismic reflection data does not have. This is something to do with coupling between antennae and the ground surface. Because of this, the GPR data should be treated differently from the seismic signal data processing work flow. Even though most of the processing steps still follow the same work flow of seismic reflection data such as: filtering, predictive deconvolution etc. This paper presents the work flow of GPR processing data on rigid pavement measurements. The processing steps start from raw data, de-Wow process, remove DC and continue with the standard process to get rid of noises i.e. filtering process. Some radargram particular features of rigid pavement along with pile foundations are presented
Frames and generalized shift-invariant systems
DEFF Research Database (Denmark)
Christensen, Ole
2004-01-01
With motivation from the theory of Hilbert-Schmidt operators we review recent topics concerning frames in L 2 (R) and their duals. Frames are generalizations of orthonormal bases in Hilbert spaces. As for an orthonormal basis, a frame allows each element in the underlying Hilbert space to be writ......With motivation from the theory of Hilbert-Schmidt operators we review recent topics concerning frames in L 2 (R) and their duals. Frames are generalizations of orthonormal bases in Hilbert spaces. As for an orthonormal basis, a frame allows each element in the underlying Hilbert space...
Monolithic LTCC seal frame and lid
Energy Technology Data Exchange (ETDEWEB)
Krueger, Daniel S.; Peterson, Kenneth A.; Stockdale, Dave; Duncan, James Brent; Riggs, Bristen
2016-06-21
A method for forming a monolithic seal frame and lid for use with a substrate and electronic circuitry comprises the steps of forming a mandrel from a ceramic and glass based material, forming a seal frame and lid block from a ceramic and glass based material, creating a seal frame and lid by forming a compartment and a plurality of sidewalls in the seal frame and lid block, placing the seal frame and lid on the mandrel such that the mandrel fits within the compartment, and cofiring the seal frame and lid block.
Energy Technology Data Exchange (ETDEWEB)
Numajiri, S. [Mitsubishi Motor Corp., Tokyo (Japan); Tamura, Y. [Mitsubishi Automotive Engineering Co. Ltd., Tokyo (Japan)
1997-10-01
A crankshaft bending stress analysis method using an elastically supported continuous beam model has been established based on the exact evaluation of the stress concentration at fillet R sections and the crankshaft rigidity. Through various examinations, it was revealed that the calculation results of the bending stress well agreed with the actual measurements. This allowed the reliability analysis and the rigidity analysis to be used to determine optimized crankshaft specifications and web shape, which in turn made it possible to apply this method to the weight reduction of a crankshaft (material removal from web). 1 ref., 7 figs., 1 tab.
Li, Yuanyuan; Wang, Zilu; Wang, Cong; Huang, Wenhu
2018-01-01
Based on Nodal Coordinate Formulation (NCF) and Absolute Nodal Coordinate Formulation (ANCF), this paper establishes rigid-flexible coupling dynamic model of the spacecraft with large deployable solar arrays and multiple clearance joints to analyze and control the satellite attitude under deployment disturbance. Considering torque spring, close cable loop (CCL) configuration and latch mechanisms, a typical spacecraft composed of a rigid main-body described by NCF and two flexible panels described by ANCF is used as a demonstration case. Nonlinear contact force model and modified Coulomb friction model are selected to establish normal contact force and tangential friction model, respectively. Generalized elastic force are derived and all generalized forces are defined in the NCF-ANCF frame. The Newmark-β method is used to solve system equations of motion. The availability and superiority of the proposed model is verified through comparing with numerical co-simulations of Patran and ADAMS software. The numerical results reveal the effects of panel flexibility, joint clearance and their coupling on satellite attitude. The effects of clearance number, clearance size and clearance stiffness on satellite attitude are investigated. Furthermore, a proportional-differential (PD) attitude controller of spacecraft is designed to discuss the effect of attitude control on the dynamic responses of the whole system.
[Arterial rigidity in patients with chronic obstructive pulmonary disease].
Karoli, N A; Dolishniaia, G R; Rebrov, A P
2012-01-01
The aim of this open study was to estimate arterial rigidity in patients with chronic obstructive pulmonary disease (COPD). It included 105 patients above 40 years of age. Exclusion criteria were clinical signs of CHD, peripheral atherosclerosis, and other severe chronic diseases in the exacerbation phase. The control group was comprised of 27 practically healthy volunteers. The arterial fluid was detected using a Tensioclinic arteriograph (Tensiomed, Hungary). Arterial rigidity was estimated in patients of two age groups (below and above 60 years) with COPD of different severity The results suggest the development of arterial wall lesions in proportion to the patients' age and COPD severity. It was shown that excessive arterial rigidity and accelerated pulse wave reflection (increased speed of pulse wave propagation and augmentation index) exert significant influence on the elevation of central arterial pressure. Enhanced rigidity of the arterial wall being a cardiovascular risk factor further prospective studies are needed.
Resin Infusion Rigidized Inflatable Concept Development and Demonstration
National Aeronautics and Space Administration — A novel concept utilizing resin infusion to rigidize inflatable structures was developed at JSC ES. This ICA project intends to complete manufacturing of a prototype...
Rigid body motion in stereo 3D simulation
International Nuclear Information System (INIS)
Zabunov, Svetoslav
2010-01-01
This paper addresses the difficulties experienced by first-grade students studying rigid body motion at Sofia University. Most quantities describing the rigid body are in relations that the students find hard to visualize and understand. They also lose the notion of cause-result relations between vector quantities, such as the relation between torque and angular momentum. Consequently, the understanding of physical laws and conservation principles in free rigid body motion is hampered. This paper presents the capabilities of a 3D simulation, which aims to clarify these questions to the students, who are taught mechanics in the general physics course. The rigid body motion simulations may be observed at http://ialms.net/sim/, and are intended to complement traditional learning practices, not replace them, as the author shares the opinion that no simulation may fully resemble reality.
Resin Infusion Rigidized Inflatable Concept Development and Demonstration Project
National Aeronautics and Space Administration — Utilizing resin infusion to rigidize an inflatable structure and form fiber-reinforced composites on-orbit is a novel concept that builds on current NASA technology...
Re-analysis of exponential rigid-rotor astron equilibria
International Nuclear Information System (INIS)
Lovelace, R.V.; Larrabee, D.A.; Fleischmann, H.H.
1978-01-01
Previous studies of exponential rigid-rotor astron equilibria include particles which are not trapped in the self-field of the configuration. The modification of these studies required to exclude untrapped particles is derived
Genus Ranges of 4-Regular Rigid Vertex Graphs.
Buck, Dorothy; Dolzhenko, Egor; Jonoska, Nataša; Saito, Masahico; Valencia, Karin
2015-01-01
A rigid vertex of a graph is one that has a prescribed cyclic order of its incident edges. We study orientable genus ranges of 4-regular rigid vertex graphs. The (orientable) genus range is a set of genera values over all orientable surfaces into which a graph is embedded cellularly, and the embeddings of rigid vertex graphs are required to preserve the prescribed cyclic order of incident edges at every vertex. The genus ranges of 4-regular rigid vertex graphs are sets of consecutive integers, and we address two questions: which intervals of integers appear as genus ranges of such graphs, and what types of graphs realize a given genus range. For graphs with 2 n vertices ( n > 1), we prove that all intervals [ a, b ] for all a genus ranges. For graphs with 2 n - 1 vertices ( n ≥ 1), we prove that all intervals [ a, b ] for all a genus ranges. We also provide constructions of graphs that realize these ranges.
A Concise Introduction to Mechanics of Rigid Bodies Multidisciplinary Engineering
Huang, L
2012-01-01
A Concise Introduction to Mechanics of Rigid Bodies: Multidisciplinary Engineering presents concise, key concepts of kinematics and dynamics of rigid bodies. This compact volume bridges the steep gap between introductory texts on engineering mechanics, which focus on one and two dimensional motions of particles and rigid bodies, and advanced texts on multi-body dynamics in high dimension spaces found in multidisciplinary areas like mechatronics, robotics and biomechanics. In the book, rigid body motions in the spaces with different dimensions are described in addition to studies in a uniform framework supported by vector and matrix operations. Rigorous mathematic tools and explanations are provided to clarify the most complex concepts. This book also: Provides practical examples from different engineering areas, offering a link between theoretical fundamentals and everyday applications Offers simplified mathematical equations to clearly present essential theories in robotics and mechanics Presents statics...
Stabilization of Rigid Body Dynamics by Internal and External Torques
National Research Council Canada - National Science Library
Bloch, A. M; Krishnaprasad, P. S; Marsden, J. E; Sanchez de Alvarez, G
1990-01-01
...] with quadratic feedback torques for internal rotors. We show that with such torques, the equations for the rigid body with momentum wheels are Hamiltonian with respect to a Lie-Poisson bracket structure. Further...
Rigidity theorem for Willmore surfaces in a sphere
Indian Academy of Sciences (India)
Home; Journals; Proceedings – Mathematical Sciences; Volume 126; Issue 2. Rigidity ... Center of Mathematical Sciences, Zhejiang University, Hangzhou 310027, People's Republic of China; College of Mathematics and Information Science, Jiangxi Normal University, Nanchang 330022, People's Republic of China ...
Boundary shear stress along rigid trapezoidal bends
Christopher I. Thornton; Kyung-Seop Sin; Paul Sclafani; Steven R. Abt
2012-01-01
The migration of alluvial channels through the geologic landform is an outcome of the natural erosive processes. Mankind continually attempts to stabilize channel meandering processes, both vertically and horizontally, to reduce sediment discharge, provide boundary definition, and enable economic development along the river's edge. A critical component in the...
“Mind the Trap”: Mindfulness Practice Reduces Cognitive Rigidity
Greenberg, Jonathan; Reiner, Keren; Meiran, Nachshon
2012-01-01
Two experiments examined the relation between mindfulness practice and cognitive rigidity by using a variation of the Einstellung water jar task. Participants were required to use three hypothetical jars to obtain a specific amount of water. Initial problems were solvable by the same complex formula, but in later problems ("critical" or "trap" problems) solving was possible by an additional much simpler formula. A rigidity score was compiled through perseverance of the complex formula. In Exp...
Probing protein ensemble rigidity and hydrogen-deuterium exchange.
Sljoka, Adnan; Wilson, Derek
2013-10-01
Protein rigidity and flexibility can be analyzed accurately and efficiently using the program floppy inclusion and rigid substructure topography (FIRST). Previous studies using FIRST were designed to analyze the rigidity and flexibility of proteins using a single static (snapshot) structure. It is however well known that proteins can undergo spontaneous sub-molecular unfolding and refolding, or conformational dynamics, even under conditions that strongly favor a well-defined native structure. These (local) unfolding events result in a large number of conformers that differ from each other very slightly. In this context, proteins are better represented as a thermodynamic ensemble of 'native-like' structures, and not just as a single static low-energy structure. Working with this notion, we introduce a novel FIRST-based approach for predicting rigidity/flexibility of the protein ensemble by (i) averaging the hydrogen bonding strengths from the entire ensemble and (ii) by refining the mathematical model of hydrogen bonds. Furthermore, we combine our FIRST-ensemble rigidity predictions with the ensemble solvent accessibility data of the backbone amides and propose a novel computational method which uses both rigidity and solvent accessibility for predicting hydrogen-deuterium exchange (HDX). To validate our predictions, we report a novel site specific HDX experiment which characterizes the native structural ensemble of Acylphosphatase from hyperthermophile Sulfolobus solfataricus (Sso AcP). The sub-structural conformational dynamics that is observed by HDX data, is closely matched with the FIRST-ensemble rigidity predictions, which could not be attained using the traditional single 'snapshot' rigidity analysis. Moreover, the computational predictions of regions that are protected from HDX and those that undergo exchange are in very good agreement with the experimental HDX profile of Sso AcP.
Probing protein ensemble rigidity and hydrogen-deuterium exchange
Sljoka, Adnan; Wilson, Derek
2013-10-01
Protein rigidity and flexibility can be analyzed accurately and efficiently using the program floppy inclusion and rigid substructure topography (FIRST). Previous studies using FIRST were designed to analyze the rigidity and flexibility of proteins using a single static (snapshot) structure. It is however well known that proteins can undergo spontaneous sub-molecular unfolding and refolding, or conformational dynamics, even under conditions that strongly favor a well-defined native structure. These (local) unfolding events result in a large number of conformers that differ from each other very slightly. In this context, proteins are better represented as a thermodynamic ensemble of ‘native-like’ structures, and not just as a single static low-energy structure. Working with this notion, we introduce a novel FIRST-based approach for predicting rigidity/flexibility of the protein ensemble by (i) averaging the hydrogen bonding strengths from the entire ensemble and (ii) by refining the mathematical model of hydrogen bonds. Furthermore, we combine our FIRST-ensemble rigidity predictions with the ensemble solvent accessibility data of the backbone amides and propose a novel computational method which uses both rigidity and solvent accessibility for predicting hydrogen-deuterium exchange (HDX). To validate our predictions, we report a novel site specific HDX experiment which characterizes the native structural ensemble of Acylphosphatase from hyperthermophile Sulfolobus solfataricus (Sso AcP). The sub-structural conformational dynamics that is observed by HDX data, is closely matched with the FIRST-ensemble rigidity predictions, which could not be attained using the traditional single ‘snapshot’ rigidity analysis. Moreover, the computational predictions of regions that are protected from HDX and those that undergo exchange are in very good agreement with the experimental HDX profile of Sso AcP.
Development of stiffer and ductile glulam portal frame
Komatsu, Kohei
2017-11-01
Portal frame structures, which are constituted of straight glulam beams and columns connected semi-rigidly by steel insert gusset plate with a lot of drift pins, were the first successful glulam structures widely used in Japan. In addition to this connection system, the author invented also a new type of jointing devise for glulam structures named as "Lagscrewbolt" which had a full threaded portion at inner part to grip wooden member as well as another thread part at the end of shank to connect with other member. The initial type of "Lagscrewbolt" was successfully applied to a various types of glulam buildings which could be rapidly built-up on construction site. Its strength performance, however, was rather brittle therefore the improvement of the ductility was a crucial research subject. In order to give a sufficient ductility on the "Lagscrewbolted joint system", so-called "Slotted Bolted Connection" concept was adopted for making use of large energy dissipation characteristics due to high-tension bolted steel connection with slotted bolt holes. Static & dynamic performance of glulam portal frame specimens was evaluated by static cyclic loading test as well as shaking table test. Current latest form of the jointing system can show very high ductility as well as stable hysteretic cyclic loops by inserting brass-shim between steel-to-steel friction interfaces
Decomposition of Riesz frames and waveletsinto a finite union of linearly independent sets
DEFF Research Database (Denmark)
Christensen, Ole; Lindner, Alexander M
2002-01-01
We characterize Riesz frames and prove that every Riesz frame is the union of a finite number of Riesz sequences. Furthermore, it is shown that for piecewise continuous wavelets with compact support, the associated regular wavelet systems can be decomposed into a finite number of linearly indepen...
A Unified Transform for LTI Systems--Presented as a (Generalized) Frame
Feuer, A.; Van Den Hof, P.M.J.; Heuberger, P.S.C.
2006-01-01
We present a set of functions in L2([0,8)) and show it to be a (tight) generalized frame (as presented by G. Kaiser (1994)). The analysis side of the frame operation is called the continuous unified transform. We show that some of the well-known transforms (such as Laplace, Laguerre, Kautz, and
A Boolean extension of a frame and a representation of discontinuity ...
African Journals Online (AJOL)
Point-free modeling of mappings that are not necessarily continuous has been so far based on the extension of a frame to its frame of sublocales, mimicking the replacement of a topological space by its discretization. This otherwise successful procedure has, however, certain disadvantages making it not quite parallel with ...
Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation
Energy Technology Data Exchange (ETDEWEB)
Arena, Lois B. [Steven Winter Associates, Inc., Norwalk, CT (United States). Consortium for Advanced Residential Buildings (CARB)
2016-07-13
High R-value wall assemblies (R-40 and above) are gaining popularity in the market due to programs such as the U.S. Department of Energy Zero Energy Ready Home program, Passive House, Net Zero Energy Home challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used double-wall systems to achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double-wall systems is that there are very few new exterior details. Exterior sheathings, structural bracings, house wraps or building paper, window and door flashings, and siding attachments are usually identical to good details in conventional framed-wall systems. However, although the details in double-wall systems are very similar to those in conventional stick framing, there is sometimes less room for error. Several studies have confirmed colder temperatures of exterior sheathing in high R-value wall assemblies that do not have exterior rigid foam insulation. These colder temperatures can lead to increased chances for condensation from air exfiltration, and they have the potential to result in moisture-related problems (Straube and Smegal 2009, Arena 2014, Ueno 2015). The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and reduce material brought to landfills due to failures and resulting decay. Although this document focuses on double-wall framing techniques, the majority of the information about how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture-related damage and are intended for builders, framing contractors, architects, and
Reciprocal frame architecture in Japan
POPOVIC LARSEN, Olga
2010-01-01
p. 1866-1876 Reciprocal Frame Structures (RF) are a form of a three-dimensional grillage structure. In their simplest configuration they are formed by placing beams in a closed circuit in which each beam is supported by the preceding beam at the inner end, and by an external wall or ring beam on the outer end. In their more complex configurations gridshell-like structures with a double curvature can be formed. Although RFs have been used in many countries throughout history and are k...
Mechanical Energy Change in Inertial Reference Frames
Ghanbari, Saeed
2016-01-01
The mechanical energy change of a system in an inertial frame of reference equals work done by the total nonconservative force in the same frame. This relation is covariant under the Galilean transformations from inertial frame S to S', where S' moves with constant velocity relative to S. In the presence of nonconservative forces, such as normal…
Oversampling of wavelet frames for real dilations
DEFF Research Database (Denmark)
Bownik, Marcin; Lemvig, Jakob
2012-01-01
We generalize the Second Oversampling Theorem for wavelet frames and dual wavelet frames from the setting of integer dilations to real dilations. We also study the relationship between dilation matrix oversampling of semi-orthogonal Parseval wavelet frames and the additional shift invariance gain...
Influence of framing on medical decision making
Gong, Jingjing; Zhang, Yan; Feng, Jun; Huang, Yonghua; Wei, Yazhou; Zhang, Weiwei
2013-01-01
Numerous studies have demonstrated the robustness of the framing effect in a variety of contexts, especially in medical decision making. Unfortunately, research is still inconsistent as to how so many variables impact framing effects in medical decision making. Additionally, much attention should be paid to the framing effect not only in hypothetical scenarios but also in clinical experience.
Fight or flight: Affective news framing effects
Feinholdt, A.
2016-01-01
This dissertation investigates how emotions shape and are shaped by news framing and how this interplay leads to a number of affective news framing effects. My work reveals that emotions do not only function as mechanisms but also as channels strengthening or weakening framing effects. In addition,
Computable Frames in Computable Banach Spaces
Directory of Open Access Journals (Sweden)
S.K. Kaushik
2016-06-01
Full Text Available We develop some parts of the frame theory in Banach spaces from the point of view of Computable Analysis. We define computable M-basis and use it to construct a computable Banach space of scalar valued sequences. Computable Xd frames and computable Banach frames are also defined and computable versions of sufficient conditions for their existence are obtained.
Influence of framing on medical decision making
Gong, Jingjing; Zhang, Yan; Feng, Jun; Huang, Yonghua; Wei, Yazhou; Zhang, Weiwei
2013-01-01
Numerous studies have demonstrated the robustness of the framing effect in a variety of contexts, especially in medical decision making. Unfortunately, research is still inconsistent as to how so many variables impact framing effects in medical decision making. Additionally, much attention should be paid to the framing effect not only in hypothetical scenarios but also in clinical experience. PMID:27034630
21 CFR 886.5842 - Spectacle frame.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Spectacle frame. 886.5842 Section 886.5842 Food... DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5842 Spectacle frame. (a) Identification. A spectacle frame is a device made of metal or plastic intended to hold prescription spectacle lenses worn by a...
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Time frames. 710.35 Section 710.35 Energy DEPARTMENT OF... Matter or Special Nuclear Material Miscellaneous § 710.35 Time frames. Statements of time established for processing aspects of a case under this subpart are the agency's desired time frames in implementing the...
Evaluation and the Framing of Race
House, Ernest R.
2017-01-01
Racial framing can have strong effects on programs, policies, and even evaluations. Racial framing developed as a justification for the exploitation of minorities and has been a primary causal factor in the persistence of racism. By being aware of its pattern, structure, origins, and how racial framing generates effects, we can significantly…
PARAMETRIC RESONANSE IN STATICALLY INDETERMINATE FRAMES
Directory of Open Access Journals (Sweden)
Yu.V. Vorona
2014-12-01
Full Text Available The technique for development and reduction of discrete dynamics models of frames is presented. Construction of the models is carried out using finite element method, generalized coordinates and tools of modern computer software. Parametric resonance in a statically indeterminate frame caused by external excitations is investigated. Main instability domains of the frame are determined.
Parametric Study Of Window Frame Geometry
DEFF Research Database (Denmark)
Zajas, Jan Jakub; Heiselberg, Per
2013-01-01
This paper describes a parametric study on window frame geometry with the goal of designing frames with very good thermal properties. Three different parametric frame models are introduced, deseribed by a number of variables. In the first part of the study, a process of sensitivity analysis...
International Nuclear Information System (INIS)
Haj Kacem, Yassine; Hadj-Taieb, Ezzedine
2017-01-01
A numerical solution based on the finite element method is presented to describe wave propagations in the transient flow of homogeneous gas-liquid mixtures in rigid and quasi-rigid pipes. The rigid model is deduced by neglecting the liquid compressibility and the pipe wall elasticity against the gas compressibility. But, these two parameters are taken into consideration in the quasi-rigid model. The effect of fluid compressibility on the pressure waves of transient flow is then analyzed and confronted to the pipe wall elasticity. To validate the reliability of the model presented herein, the numerical results are compared with those obtained by the finite difference method and experiment. The results show that the pressure wave propagation is significantly influenced by gas-fluid mass ratio and pipe wall elasticity. (authors)
An Automated Analysis-Synthesis Package for Design Optimization ...
African Journals Online (AJOL)
90 standards is developed for the design optimization of framed structures - continuous beams, plane and space trusses and rigid frames, grids and composite truss-rigid frames. The package will enable the structural engineer to effectively and ...
Joint Center Estimation Using Single-Frame Optimization: Part 1: Numerical Simulation
Directory of Open Access Journals (Sweden)
Eric Frick
2018-04-01
Full Text Available The biomechanical models used to refine and stabilize motion capture processes are almost invariably driven by joint center estimates, and any errors in joint center calculation carry over and can be compounded when calculating joint kinematics. Unfortunately, accurate determination of joint centers is a complex task, primarily due to measurements being contaminated by soft-tissue artifact (STA. This paper proposes a novel approach to joint center estimation implemented via sequential application of single-frame optimization (SFO. First, the method minimizes the variance of individual time frames’ joint center estimations via the developed variance minimization method to obtain accurate overall initial conditions. These initial conditions are used to stabilize an optimization-based linearization of human motion that determines a time-varying joint center estimation. In this manner, the complex and nonlinear behavior of human motion contaminated by STA can be captured as a continuous series of unique rigid-body realizations without requiring a complex analytical model to describe the behavior of STA. This article intends to offer proof of concept, and the presented method must be further developed before it can be reasonably applied to human motion. Numerical simulations were introduced to verify and substantiate the efficacy of the proposed methodology. When directly compared with a state-of-the-art inertial method, SFO reduced the error due to soft-tissue artifact in all cases by more than 45%. Instead of producing a single vector value to describe the joint center location during a motion capture trial as existing methods often do, the proposed method produced time-varying solutions that were highly correlated (r > 0.82 with the true, time-varying joint center solution.
Randomized trial comparing office flexible to rigid cystoscopy in women.
Quiroz, Lieschen H; Shobeiri, S Abbas; Nihira, Mikio A; Brady, Jordan; Wild, Robert A
2012-11-01
The objective of the study was to compare office rigid cystoscopy (RC) versus flexible cystoscopy (FC) in women. This was a prospective randomized trial comparing FC to RC. Aims were to assess 1-week post-procedural complications, compare procedure pain scores, and to assess physician perception of patient discomfort. Pain scores were assessed by visual analogue scale (VAS) and 5-point verbal descriptor scale (VDS). Chi-square was used for categorical comparison and t tests or Wilcoxon test for continuous variables. One hundred women were enrolled. The mean age of participants was 59.7 years (± SD 14.6), and 91 % were Caucasian. This was the first cystoscopy for 86 % of participants. On the 1-week post-procedure questionnaire (85 % response rate), participants in the FC group reported urinary frequency more often than in the RC group (p = 0.041). The FC group reported urgency with urination lasting 1-2 days (p = 0.030) and burning with urination lasting >3 days (p = 0.026), more than the RC group. These symptoms did not persist at 7 days. The duration of the procedure was slightly faster for the FC group (4.6 ± 1.8 min vs 5.7 ± 3.4 min, p = 0.046). Median VAS scores were 0.9 (0.1-2.72) for the FC group and 0.5 (0-2.4) for the RC group (p = 0.505). There were no significant differences between patient or physician perception of pain in either group. Urinary frequency and duration of urinary burning post procedure occurred more frequently in the FC group, although these symptoms were transient. Both office FC and RC are generally well tolerated in women with overall low morbidity.
The method for staining of anterior lens capsule in cases with small and rigid pupils
Directory of Open Access Journals (Sweden)
V. Kumar
2012-01-01
Full Text Available Purpose: to evaluate the safety and effectiveness of proposed method for staining with trypan blue anterior lens capsule in cases with small and rigid pupils.Methods: the safety and effectiveness of the proposed method was evaluated in 169 cases having small and rigid pupils of III and IV grade. Surgical steps included: irrigation of anterior chamber with small amount of air, enough to block the pupil; irrigation of posterior chamber with little amount of dye followed by aspiration of air bubble. the excess dye came out and stained the capsule in pupillary area.Results: No difficulty was encountered in irrigating the posterior chamber with dye. Uneven staining of the capsule was noticed in 16 cases (9.5%. In 3 cases (1.8% extensive staining of iris and posterior capsule was observed. Continuous curvilinear capsulorhexis was performed successfully in 97.6% cases. In 4 cases there was radial run of the rhexis extending up to posterior capsule. Postopera- tive inflammation of 1st and 2nd degree was observed in 5.9 and 23.1% cases, which was related to unavoidable trauma to iris tissue during pupil stretching.Conclusion: the proposed method of capsule staining in cases with small and rigid pupils is safe and effective.
The method for staining of anterior lens capsule in cases with small and rigid pupils
Directory of Open Access Journals (Sweden)
V. Kumar
2014-07-01
Full Text Available Purpose: to evaluate the safety and effectiveness of proposed method for staining with trypan blue anterior lens capsule in cases with small and rigid pupils.Methods: the safety and effectiveness of the proposed method was evaluated in 169 cases having small and rigid pupils of III and IV grade. Surgical steps included: irrigation of anterior chamber with small amount of air, enough to block the pupil; irrigation of posterior chamber with little amount of dye followed by aspiration of air bubble. the excess dye came out and stained the capsule in pupillary area.Results: No difficulty was encountered in irrigating the posterior chamber with dye. Uneven staining of the capsule was noticed in 16 cases (9.5%. In 3 cases (1.8% extensive staining of iris and posterior capsule was observed. Continuous curvilinear capsulorhexis was performed successfully in 97.6% cases. In 4 cases there was radial run of the rhexis extending up to posterior capsule. Postopera- tive inflammation of 1st and 2nd degree was observed in 5.9 and 23.1% cases, which was related to unavoidable trauma to iris tissue during pupil stretching.Conclusion: the proposed method of capsule staining in cases with small and rigid pupils is safe and effective.
Continuous auditing & continuous monitoring : Continuous value?
van Hillo, Rutger; Weigand, Hans; Espana, S; Ralyte, J; Souveyet, C
2016-01-01
Advancements in information technology, new laws and regulations and rapidly changing business conditions have led to a need for more timely and ongoing assurance with effectively working controls. Continuous Auditing (CA) and Continuous Monitoring (CM) technologies have made this possible by
DEFF Research Database (Denmark)
Lazarov, Boyan Stefanov; Ditlevsen, Ove
2005-01-01
The object of study is a stationary Gaussian white noise excited plane multistory shear frame with a large number of rigid traverses. All the traverse-connecting columns have finite symmetrical yield limits except the columns in one or more of the bottom floors. The columns behave linearly elastic...... within the yield limits and ideally plastic outside these without accumulating eigenstresses. Within the elastic domain the frame is modeled as a linearly damped oscillator. The white noise excitation acts on the mass of the first floor making the movement of the elastic bottom floors simulate a ground...
Nonlinear pushover analysis of infilled concrete frames
Huang, Chao Hsun; Tuan, Yungting Alex; Hsu, Ruo Yun
2006-12-01
Six reinforced concrete frames with or without masonry infills were constructed and tested under horizontal cyclic loads. All six frames had identical details in which the transverse reinforcement in columns was provided by rectangular hoops that did not meet current ACI specifications for ductile frames. For comparison purposes, the columns in three of these frames were jacketed by carbon-fiber-reinforced-polymer (CFRP) sheets to avoid possible shear failure. A nonlinear pushover analysis, in which the force-deformation relationships of individual elements were developed based on ACI 318, FEMA 356, and Chen’s model, was carried out for these frames and compared to test results. Both the failure mechanisms and impact of infills on the behaviors of these frames were examined in the study. Conclusions from the present analysis provide structural engineers with valuable information for evaluation and design of infilled concrete frame building structures.
An introduction to finite tight frames
Waldron, Shayne F D
2018-01-01
This textbook is an introduction to the theory and applications of finite tight frames, an area that has developed rapidly in the last decade. Stimulating much of this growth are the applications of finite frames to diverse fields such as signal processing, quantum information theory, multivariate orthogonal polynomials, and remote sensing. Key features and topics: * First book entirely devoted to finite frames * Extensive exercises and MATLAB examples for classroom use * Important examples, such as harmonic and Heisenberg frames, are presented in preliminary chapters, encouraging readers to explore and develop an intuitive feeling for tight frames * Later chapters delve into general theory details and recent research results * Many illustrations showing the special aspects of the geometry of finite frames * Provides an overview of the field of finite tight frames * Discusses future research directions in the field Featuring exercises and MATLAB examples in each chapter, the book is well suited as a textbook ...
Analisis Framing dalam Riset Public Relations
Directory of Open Access Journals (Sweden)
NARAYANA MAHENDRA PRASTYA
2016-12-01
Full Text Available This paper aims to give description about how to use frame analysis in Public Relations (PR research. The author use two framing models: Entman and Pan & Kosicki. The object is organization official statement about particular issue. Frame analysis method rarely used in Public Relations research. This methods commonly use in journalism study, to analyse the news in media. Meanwhile, the key word of framing is the social construction of reality. Organization can make social construction of realty in their official statement. In acacemic term, frame analysis in PR research is useful to know how organization positioned themselves in particular situation. Other benefit is use to evaluat whether the organization frame is conformable with the public opinion or agenda setting media or not. In practical term, frame analysis give benefit for PR practitioner to create the message that can be undserstood by public, also give positive image for organization.
Characterization of Oblique Dual Frame Pairs
DEFF Research Database (Denmark)
Christensen, Ole; Eldar, Yonina
2006-01-01
Given a frame for a subspace W of a Hilbert space H, we consider all possible families of oblique dual frame vectors on an appropriately chosen subspace V. In place of the standard description, which involves computing the pseudoinverse of the frame operator, we develop an alternative...... characterization which in some cases can be computationally more efficient. We first treat the case of a general frame on an arbitrary Hilbert space, and then specialize the results to shift-invariant frames with multiple generators. In particular, we present explicit versions of our general conditions...... for the case of shift-invariant spaces with a single generator. The theory is also adapted to the standard frame setting in which the original and dual frames are defined on the same space. Copyright (C) 2006 Hindawi Publishing Corporation. All rights reserved....
Directory of Open Access Journals (Sweden)
Xiaojia Xiang
2015-01-01
Full Text Available The collocation method is extended to the special orthogonal group SO(3 with application to optimal attitude control (OAC of a rigid body. A left-invariant rigid-body attitude dynamical model on SO(3 is established. For the left invariance of the attitude configuration equation in body-fixed frame, a geometrically exact numerical method on SO(3, referred to as the geometric collocation method, is proposed by deriving the equivalent Lie algebra equation in so(3 of the left-invariant configuration equation. When compared with the general Gauss pseudo-spectral method, the explicit RKMK, and Lie group variational integrator having the same order and stepsize in numerical tests for evolving a free-floating rigid-body attitude dynamics, the proposed method is higher in accuracy, time performance, and structural conservativeness. In addition, the numerical method is applied to solve a constrained OAC problem on SO(3. The optimal control problem is transcribed into a nonlinear programming problem, in which the equivalent Lie algebra equation is being considered as the defect constraints instead of the configuration equation. The transcription method is coordinate-free and does not need chart switching or special handling of singularities. More importantly, with the numerical advantage of the geometric collocation method, the proposed OAC method may generate satisfying convergence rate.
General terms and rigidity: another solution to the trivialization problem
Directory of Open Access Journals (Sweden)
Eleonora Orlando
2014-06-01
Full Text Available In this paper I am concerned with the problem of applying the notion of rigidity to general terms. In Naming and Necessity, Kripke has clearly suggested that we should include some general terms among the rigid ones, namely, those common nouns semantically correlated with natural substances, species and phenomena, in general, natural kinds -'water', 'tiger', 'heat'- and some adjectives -'red', 'hot', 'loud'. However, the notion of rigidity has been defined for singular terms; after all, the notion that Kripke has provided us with is the notion of a rigid designator. But general terms do not designate single individuals: rather, they apply to many of them. In sum, the original concept of rigidity cannot be straightforwardly applied to general terms: it has to be somehow redefined in order to make it cover them. As is known, two main positions have been put forward to accomplish that task: the identity of designation conception, according to which a rigid general term is one that designates the same property or kind in all possible worlds, and the essentialist conception, which conceives of a rigid general term as an essentialist one, namely, a term that expresses an essential property of an object. My purpose in the present paper is to defend a particular version of the identity of designation conception: on the proposed approach, a rigid general term will be one that expresses the same property in all possible worlds and names the property it expresses. In my opinion, the position can be established on the basis of an inference to the best explanation of our intuitive interpretation and evaluation, relative to counterfactual circumstances, of statements containing different kinds of general terms, which is strictly analogous to our intuitive interpretation and evaluation, relative to such circumstances, of statements containing different kinds of singular ones. I will argue that it is possible to offer a new solution to the trivialization
Discursive Framings of Human Rights
DEFF Research Database (Denmark)
What does it mean to be a subject of human rights? The status of the subject is closely connected with the form and rhetoric of the framing discourse, and this book investigates the relationship between the status of the subject and the form of human rights discourse, in differing aesthetic...... and social contexts. Historical as well as contemporary declarations of rights have stressed both the protective and political aspects of human rights. But in concrete situations and conflictual moments, the high moral legitimacy of human rights rhetoric has often clouded the actual character of specific...... interventions, and so made it difficult to differentiate between the objects of humanitarian intervention and the subjects of politics. Critically re-examining this opposition – between victims and agents of human rights – through a focus on the ways in which discourses of rights are formed and circulated...
Soft-matter composites with electrically tunable elastic rigidity
Shan, Wanliang; Lu, Tong; Majidi, Carmel
2013-08-01
We use a phase-changing metal alloy to reversibly tune the elastic rigidity of an elastomer composite. The elastomer is embedded with a sheet of low-melting-point Field’s metal and an electric Joule heater composed of a serpentine channel of liquid-phase gallium-indium-tin (Galinstan®) alloy. At room temperature, the embedded Field’s metal is solid and the composite remains elastically rigid. Joule heating causes the Field’s metal to melt and allows the surrounding elastomer to freely stretch and bend. Using a tensile testing machine, we measure that the effective elastic modulus of the composite reversibly changes by four orders of magnitude when powered on and off. This dramatic change in rigidity is accurately predicted with a model for an elastic composite. Reversible rigidity control is also accomplished by replacing the Field’s metal with shape memory polymer. In addition to demonstrating electrically tunable rigidity with an elastomer, we also introduce a new technique to rapidly produce soft-matter electronics and multifunctional materials in several minutes with laser-patterned adhesive film and masked deposition of liquid-phase metal alloy.
Evaluation for rigidity of box construction of nuclear reactor building
International Nuclear Information System (INIS)
Yamakawa, Tetsuo
1979-01-01
A huge box-shaped structure (hereafter, called box construction) of reinforced concrete is presently utilized as the reactor building structure in nuclear power plants. Evaluation of the rigidity of the huge box construction is required for making a vibration analysis model of nuclear reactor buildings. It is necessary to handle the box construction as the plates to which the force in plane is applied. This paper describes that the bending theory in elementary beam theory is equivalent to a peculiar, orthogonally anisotropic plate, the shearing rigidity and film rigidity in y direction of which are put to infinity and the Poisson's ratio is put to zero, viewed from the two-dimensional theory of elasticity. The form factor of 1.2 for shearing deformation in rectangular cross section was calculated from the parabolic distribution of shearing stress intensity, and it is the maximum value. The factor is equal to 1.2 for slender beams, but smaller than 1.2 for short and thick beams, having tendency to converge to 1.0. The non-conformity of boundary conditions regarding the shearing force at the both ends of cantilevers does not affect very seriously the evaluation of shearing rigidity. From the above results, it was found that the application of the theory to the box construction was able to give the rigidity evaluation with sufficient engineering accuracy. The theory can also be applied to the evaluation of tube type ultrahigh buildings. (Wakatsuki, Y.)
Unified Creep Plasticity Damage (UCPD) Model for Rigid Polyurethane Foams.
Energy Technology Data Exchange (ETDEWEB)
Neilsen, Michael K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lu, Wei-Yang [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scherzinger, William M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hinnerichs, Terry D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lo, Chi S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-06-01
Numerous experiments were performed to characterize the mechanical response of several different rigid polyurethane foams (FR3712, PMDI10, PMDI20, and TufFoam35) to large deformation. In these experiments, the effects of load path, loading rate, and temperature were investigated. Results from these experiments indicated that rigid polyurethane foams exhibit significant volumetric and deviatoric plasticity when they are compressed. Rigid polyurethane foams were also found to be very strain-rate and temperature dependent. These foams are also rather brittle and crack when loaded to small strains in tension or to larger strains in compression. Thus, a new Unified Creep Plasticity Damage (UCPD) model was developed and implemented into SIERRA with the name Foam Damage to describe the mechanical response of these foams to large deformation at a variety of temperatures and strain rates. This report includes a description of recent experiments and experimental findings. Next, development of a UCPD model for rigid, polyurethane foams is described. Selection of material parameters for a variety of rigid polyurethane foams is then discussed and finite element simulations with the new UCPD model are compared with experimental results to show behavior that can be captured with this model.
Packing density of rigid aggregates is independent of scale.
Zangmeister, Christopher D; Radney, James G; Dockery, Lance T; Young, Jessica T; Ma, Xiaofei; You, Rian; Zachariah, Michael R
2014-06-24
Large planetary seedlings, comets, microscale pharmaceuticals, and nanoscale soot particles are made from rigid, aggregated subunits that are compacted under low compression into larger structures spanning over 10 orders of magnitude in dimensional space. Here, we demonstrate that the packing density (θf) of compacted rigid aggregates is independent of spatial scale for systems under weak compaction. The θf of rigid aggregated structures across six orders of magnitude were measured using nanoscale spherical soot aerosol composed of aggregates with ∼ 17-nm monomeric subunits and aggregates made from uniform monomeric 6-mm spherical subunits at the macroscale. We find θf = 0.36 ± 0.02 at both dimensions. These values are remarkably similar to θf observed for comet nuclei and measured values of other rigid aggregated systems across a wide variety of spatial and formative conditions. We present a packing model that incorporates the aggregate morphology and show that θf is independent of both monomer and aggregate size. These observations suggest that the θf of rigid aggregates subject to weak compaction forces is independent of spatial dimension across varied formative conditions.
Czech Academy of Sciences Publication Activity Database
Hlaváček, Ivan; Lovíšek, J.
2011-01-01
Roč. 91, č. 9 (2011), s. 711-723 ISSN 0044-2267 R&D Projects: GA AV ČR(CZ) IAA100190803 Institutional research plan: CEZ:AV0Z10190503 Keywords : functionally graded plate * optimal design Subject RIV: BA - General Mathematics Impact factor: 0.863, year: 2011 http://onlinelibrary.wiley.com/doi/10.1002/zamm.201000119/abstract
Witjes, J.A.; Moonen, P.M.J.; Heijden, A.G. van der
2005-01-01
INTRODUCTION AND OBJECTIVE: Several studies have shown that rigid fluorescence cystoscopy (RFC) with hexaminolevulinate (HAL) is superior to standard rigid white light (RWLC) cystoscopy in diagnosing bladder tumours, with a clinically relevant impact on the patient's management. These studies,
Efficient computation of root mean square deviations under rigid transformations.
Hildebrandt, Anna K; Dietzen, Matthias; Lengauer, Thomas; Lenhof, Hans-Peter; Althaus, Ernst; Hildebrandt, Andreas
2014-04-15
The computation of root mean square deviations (RMSD) is an important step in many bioinformatics applications. If approached naively, each RMSD computation takes time linear in the number of atoms. In addition, a careful implementation is required to achieve numerical stability, which further increases runtimes. In practice, the structural variations under consideration are often induced by rigid transformations of the protein, or are at least dominated by a rigid component. In this work, we show how RMSD values resulting from rigid transformations can be computed in constant time from the protein's covariance matrix, which can be precomputed in linear time. As a typical application scenario is protein clustering, we will also show how the Ward-distance which is popular in this field can be reduced to RMSD evaluations, yielding a constant time approach for their computation. Copyright © 2014 Wiley Periodicals, Inc.
Interaction of the rigid journal with Newtonian fluid
Michal, Havlásek; František, Pochylý
2017-09-01
This paper deals with the problem of identification of added effects of incompressible Newtonian fluid that impacts on the rigid journal performing translational motion. It considers two degrees of freedom. The axial motion of the rigid journal was neglected. It assumes small oscillations and linear model. The task was solved for two geometrical configurations of the computational domain. In the first variant of geometry, there is no flow between the bases of journal and stator. The second variant of geometry also allows liquid to flow in space between the bases of journal and stator. The introduction describes the mathematical model for the identification of added mass, damping and stiffness matrices. On the basis of the mathematical model and computational modeling of velocity and pressure fields using CFD, the force components are determined. From there, the mentioned matrices are determined depending on the eccentricity of the rigid journal.
Fibroblast motility on substrates with different rigidities: modeling approach
Gracheva, Maria; Dokukina, Irina
2009-03-01
We develop a discrete model for cell locomotion on substrates with different rigidities and simulate experiments described in Lo, Wang, Dembo, Wang (2000) ``Cell movement is guided by the rigidity of the substrate'', Biophys. J. 79: 144-152. In these experiments fibroblasts were planted on a substrate with a step rigidity and showed preference for locomotion over stiffer side of the substrate when approaches the boundary between the soft and the stiff sides of the substrate. The model reproduces experimentally observed behavior of fibroblasts. In particular, we are able to show with our model how cell characteristics (such as cell length, shape, area and speed) change during cell crawling through the ``soft-stiff'' substrate boundary. Also, our model suggests the temporary increase of both cell speed and area in that very moment when cell leaves soft side of substrate.
A concise introduction to mechanics of rigid bodies multidisciplinary engineering
Huang, L
2017-01-01
This updated second edition broadens the explanation of rotational kinematics and dynamics — the most important aspect of rigid body motion in three-dimensional space and a topic of much greater complexity than linear motion. It expands treatment of vector and matrix, and includes quaternion operations to describe and analyze rigid body motion which are found in robot control, trajectory planning, 3D vision system calibration, and hand-eye coordination of robots in assembly work, etc. It features updated treatments of concepts in all chapters and case studies. The textbook retains its comprehensiveness in coverage and compactness in size, which make it easily accessible to the readers from multidisciplinary areas who want to grasp the key concepts of rigid body mechanics which are usually scattered in multiple volumes of traditional textbooks. Theoretical concepts are explained through examples taken from across engineering disciplines and links to applications and more advanced courses (e.g. industrial rob...
Toxicity evaluation and hazard review for Rigid Foam
Energy Technology Data Exchange (ETDEWEB)
Archuleta, M.M.; Stocum, W.E.
1994-02-01
Rigid Foam is a chemical delay foam used to completely encapsulate an object or to block access to an area. Prior studies have indicated that the final foam product is essentially non-toxic. The purpose of this study was to evaluate and summarize the current chemical and toxicological data available on the components of Rigid Foam and to update the information available on the toxicity of the final Rigid Foam product. Since the possibility exists for a partial deployment of Rigid Foam where only one of the components is released, this study also examined the toxicity of its chemical constituents. Rigid Foam is composed of an {open_quotes}A{close_quotes} and {open_quotes}B{close_quotes} Component. The {open_quotes}A{close_quotes} component is primarily a polymeric isocyanate and the {open_quotes}B{close_quotes} component is a mixture of polyols. In addition to the primary constituents, dichlorodifluoromethane and trichlorofluoromethane are present as blowing agents along with catalysts and silicone surfactants necessary for foaming. The pre-deployed {open_quotes}A{close_quotes} and {open_quotes}B{close_quotes} components are stored in separate vessels and are brought together in static mixing nozzles for dispersal. The results of this evaluation indicate that a completely deployed Rigid Foam under normal conditions is essentially non-toxic as determined previously. However, in the event of a partial deployment or deployment of an individual component directly at an unprotected individual, the degree of hazard is increased due to the toxic and corrosive nature of the individual constituents. The health hazard would depend on the properties of the material to which the person was exposed.
Rigid 4D N=2 supersymmetric backgrounds and actions
Energy Technology Data Exchange (ETDEWEB)
Butter, Daniel; Inverso, Gianluca; Lodato, Ivano [Nikhef Theory Group,Science Park 105, 1098 XG Amsterdam (Netherlands)
2015-09-15
We classify all N=2 rigid supersymmetric backgrounds in four dimensions with both Lorentzian and Euclidean signature that preserve eight real supercharges, up to discrete identifications. Among the backgrounds we find specific warpings of S{sup 3}×ℝ and AdS{sub 3}×ℝ, AdS{sub 2}×S{sup 2} and H{sup 2}×S{sup 2} with generic radii, and some more exotic geometries. We provide the generic two-derivative rigid vector and hypermultiplet actions and analyze the conditions imposed on the special Kähler and hyperkähler target spaces.
Topology-Preserving Rigid Transformation of 2D Digital Images.
Ngo, Phuc; Passat, Nicolas; Kenmochi, Yukiko; Talbot, Hugues
2014-02-01
We provide conditions under which 2D digital images preserve their topological properties under rigid transformations. We consider the two most common digital topology models, namely dual adjacency and well-composedness. This paper leads to the proposal of optimal preprocessing strategies that ensure the topological invariance of images under arbitrary rigid transformations. These results and methods are proved to be valid for various kinds of images (binary, gray-level, label), thus providing generic and efficient tools, which can be used in particular in the context of image registration and warping.
Nonlinear vibration of an axially loaded beam carrying rigid bodies
Directory of Open Access Journals (Sweden)
O. Barry
2016-12-01
Full Text Available This paper investigates the nonlinear vibration due to mid-plane stretching of an axially loaded simply supported beam carrying multiple rigid masses. Explicit expressions and closed form solutions of both linear and nonlinear analysis of the present vibration problem are presented for the first time. The validity of the analytical model is demonstrated using finite element analysis and via comparison with the result in the literature. Parametric studies are conducted to examine how the nonlinear frequency and frequency response curve are affected by tension, rotational inertia, and number of intermediate rigid bodies.
Extremal surfaces and the rigidity of null geodesic incompleteness
International Nuclear Information System (INIS)
Silva, I P Costa e; Flores, J L
2015-01-01
An important, if relatively less well known aspect of the singularity theorems in Lorentzian geometry, is to understand how their conclusions fare upon weakening or suppression of one or more of their hypotheses. Then, theorems with modified conclusion may arise, showing that those conclusions will fail only in special cases, at least some of which may be described. These are the so-called rigidity theorems, and have many important examples in the specialized literature. In this paper, we prove rigidity results for generalized plane waves and certain globally hyperbolic spacetimes in the presence of extremal compact surfaces. (paper)
DEFF Research Database (Denmark)
Lazarov, Boyan Stefanov; Ditlevsen, Ove Dalager
2003-01-01
The object of study is a stationary Gaussian white noise excited MDOF linear elastic, ideal plastic, linearly damped, statically determinate oscillator with several potential elements of ideal plastic yielding. Specifically the study is exemplified for a plane multistory shear frame with rigid...... traverses where all the connecting columns except the columns in one or more of the bottom floors have finite symmetrical yield limits. The white noise excitation acts on the mass of the first floor making the movement of the elastic bottom floors simulate a ground motion that interacts with the structure...
DEFF Research Database (Denmark)
Lazarov, Boyan Stefanov; Ditlevsen, Ove Dalager
2004-01-01
The object of study is a stationary Gaussian white noise excited multi-degree-of-freedom (MDOF) linear elastic, ideal plastic, linearly damped, statically determinate oscillator with several potential elements of ideal plastic yielding. Specifically the study is exemplified for a plane multistory...... shear frame with rigid traverses where all the connecting columns except the columns in one or more of the bottom floors have finite symmetrical yield limits. The white noise excitation acts on the mass of the first floor making the movement of the elastic bottom floors simulate a ground motion...
The frame/content theory of evolution of speech production.
MacNeilage, P F
1998-08-01
The species-specific organizational property of speech is a continual mouth open-close alternation, the two phases of which are subject to continual articulatory modulation. The cycle constitutes the syllable, and the open and closed phases are segments-vowels and consonants, respectively. The fact that segmental serial ordering errors in normal adults obey syllable structure constraints suggests that syllabic "frames" and segmental "content" elements are separately controlled in the speech production process. The frames may derive from cycles of mandibular oscillation present in humans from babbling onset, which are responsible for the open-close alternation. These communication-related frames perhaps first evolved when the ingestion-related cyclicities of mandibular oscillation (associated with mastication [chewing] sucking and licking) took on communicative significance as lipsmacks, tonguesmacks, and teeth chatters--displays that are prominent in many nonhuman primates. The new role of Broca's area and its surround in human vocal communication may have derived from its evolutionary history as the main cortical center for the control of ingestive processes. The frame and content components of speech may have subsequently evolved separate realizations within two general purpose primate motor control systems: (1) a motivation-related medial "intrinsic" system, including anterior cingulate cortex and the supplementary motor area, for self-generated behavior, formerly responsible for ancestral vocalization control and now also responsible for frames, and (2) a lateral "extrinsic" system, including Broca's area and surround, and Wernicke's area, specialized for response to external input (and therefore the emergent vocal learning capacity) and more responsible for content.
Do framing effects reveal irrational choice?
Mandel, David R
2014-06-01
Framing effects have long been viewed as compelling evidence of irrationality in human decision making, yet that view rests on the questionable assumption that numeric quantifiers used to convey the expected values of choice options are uniformly interpreted as exact values. Two experiments show that when the exactness of such quantifiers is made explicit by the experimenter, framing effects vanish. However, when the same quantifiers are given a lower bound (at least) meaning, the typical framing effect is found. A 3rd experiment confirmed that most people spontaneously interpret the quantifiers in standard framing tests as lower bounded and that their interpretations strongly moderate the framing effect. Notably, in each experiment, a significant majority of participants made rational choices, either choosing the option that maximized expected value (i.e., lives saved) or choosing consistently across frames when the options were of equal expected value. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Frames in the Ethiopian Debate on Biofuels
Directory of Open Access Journals (Sweden)
Brigitte Portner
2013-01-01
Full Text Available Biofuel production, while highly contested, is supported by a number of policies worldwide. Ethiopia was among the first sub-Saharan countries to devise a biofuel policy strategy to guide the associated demand toward sustainable development. In this paper, I discuss Ethiopia’s biofuel policy from an interpretative research position using a frames approach and argue that useful insights can be obtained by paying more attention to national contexts and values represented in the debates on whether biofuel production can or will contribute to sustainable development. To this end, I was able to distinguish three major frames used in the Ethiopian debate on biofuels: an environmental rehabilitation frame, a green revolution frame and a legitimacy frame. The article concludes that actors advocating for frames related to social and human issues have difficulties entering the debate and forming alliances, and that those voices need to be included in order for Ethiopia to develop a sustainable biofuel sector.
Nonlinear approximation with nonstationary Gabor frames
DEFF Research Database (Denmark)
Ottosen, Emil Solsbæk; Nielsen, Morten
2018-01-01
We consider sparseness properties of adaptive time-frequency representations obtained using nonstationary Gabor frames (NSGFs). NSGFs generalize classical Gabor frames by allowing for adaptivity in either time or frequency. It is known that the concept of painless nonorthogonal expansions...... resolution. Based on this characterization we prove an upper bound on the approximation error occurring when thresholding the coefficients of the corresponding frame expansions. We complement the theoretical results with numerical experiments, estimating the rate of approximation obtained from thresholding...
A Formal Description of Problem Frames
Souleymane KOUSSOUBE; Roger NOUSSI; Balira O. KONFE
2014-01-01
Michael Jackson defines a Problem Frame as a mean to describe and classify software development problems. The initial description of problem Frames is essentially graphical. A weakness of this proposal is the lack of formal specification allowing efficient reasoning tools. This paper deals with Problem Frames’ formal specification with Description Logics. We first propose a formal terminology of Problem Frames leading to the specification of a Problem Frames’ TBOX and a specific problem’s ABO...
Supporting Product Line Evolution with Framed Aspects
DEFF Research Database (Denmark)
Loughran, Neil; Rashid, Awais; Zhang, Weishan
2004-01-01
This paper discusses how evolution in software product lines can be supported using framed aspects: a combination of aspect-oriented programming and frame technology. Product line architectures and assets are subject to maintenance and evolution throughout their lifetime due to the emergence of new...... of both technologies in combination. The amalgamation of framing and aspect-oriented techniques can help in the integration of new features and thus reduce the risk of architectural erosion....
High Resolution Quantification of Cellular Forces for Rigidity Sensing
Liu, Shuaimin
This thesis describes a comprehensive study of understanding the mechanism of rigidity sensing by quantitative analysis using submicron pillar array substrates. From mechanobiology perspective, we explore and study molecular pathways involved in rigidity and force sensing at cell-matrix adhesions with regard to cancer, regeneration, and development by quantification methods. In Chapter 2 and 3, we developed fabrication and imaging techniques to enhance the performance of a submicron pillar device in terms of spatial and temporal measurement ability, and we discovered a correlation of rigidity sensing forces and corresponding proteins involved in the early rigidity sensing events. In Chapter 2, we introduced optical effect arising from submicron structure imaging, and we described a technique to identify the correct focal plane of pillar tip by fabricating a substrate with designed-offset pillars. From calibration result, we identified the correct focal plane that was previously overlooked, and verified our findings by other imaging techniques. In Chapter 3, we described several techniques to selectively functionalize elastomeric pillars top and compared these techniques in terms of purposes and fabrication complexity. Techniques introduced in this chapter included direct labeling, such as stamping of fluorescent substances (organic dye, nano-diamond, q-dot) to pillars top, as well as indirect labeling that selectively modify the surface of molds with either metal or fluorescent substances. In Chapter 4, we examined the characteristics of local contractility forces and identified the components formed a sarcomere like contractile unit (CU) that cells use to sense rigidity. CUs were found to be assembled at cell edge, contain myosin II, alpha-actinin, tropomodulin and tropomyosin (Tm), and resemble sarcomeres in size (˜2 mum) and function. Then we performed quantitative analysis of CUs to evaluate rigidity sensing activity over ˜8 hours time course and found that
Morphogenesis of Kinetic Reciprocal Frames
DEFF Research Database (Denmark)
Parigi, Dario; Sassone, Mario
2011-01-01
Kinetic structures in civil engineering and architecture gained considerable more attention in the very recent years as a practical solution to face time dependant performances. Realized projects are mostly bridges, retractable roofs, while in architecture the trend follows the category of intera......Kinetic structures in civil engineering and architecture gained considerable more attention in the very recent years as a practical solution to face time dependant performances. Realized projects are mostly bridges, retractable roofs, while in architecture the trend follows the category...... (RF) were studied in the past as a practical solution to span distances with shorter elements. Leonardo da Vinci discovered interesting RF patterns and studied three dimensional arch structures for bridges. RF are generally defined as structures that forms closed circuits of forces, and where elements...... joins in intermediate points. In the present paper we will describe a new subset of kinetic structures based on reciprocal frames topology and pin-slot constraint, a connection where a pin is constrained to move along a slot, and to rotate around its axis. The first step in obtaining a kinetic...
Flat-field and Dark Frame Corrections for IRIS Data
Saar, S. H.; Jaeggli, S. A.; Bush, R. I.; Boerner, P.; Wuelser, J.; Tarbell, T. D.; Lites, B. W.; De Pontieu, B.
2013-12-01
We discuss the development of flat-field and dark frame corrections for Interface Region Imaging Spectrograph (IRIS) data. Flat-fields for IRIS were taken prior to launch using a lamp filtered to NUV wavelengths; following launch the Sun itself was used as a flat-field source. The solar flat-field for the slit-jaw imagers is constructed using the Chae method, which extracts the moving object and fixed gain patterns from a set of dithered images. The spectrographic flat-fields are produced by significantly defocusing the telescope and averaging many images in a scan to remove solar structure, so that the average spectral profile can be removed. A given dark frame consists of pedestal and dark current components. In IRIS, both are temperature dependent, though they respond to different measured temperatures; the dark current is also exposure time dependent. Each CCD readout port has a slightly different temperature and exposure time response. We have analyzed a series of dark frames over an IRIS orbit to calibrate for these effects. We plan to continue to monitor the flat-field and dark frames regularly for any changes.
A novel simultaneous streak and framing camera without principle errors
Jingzhen, L.; Fengshan, S.; Ningwen, L.; Xiangdong, G.; Bin, H.; Qingyang, W.; Hongyi, C.; Yi, C.; Xiaowei, L.
2018-02-01
A novel simultaneous streak and framing camera with continuous access, the perfect information of which is far more important for the exact interpretation and precise evaluation of many detonation events and shockwave phenomena, has been developed. The camera with the maximum imaging frequency of 2 × 106 fps and the maximum scanning velocity of 16.3 mm/μs has fine imaging properties which are the eigen resolution of over 40 lp/mm in the temporal direction and over 60 lp/mm in the spatial direction and the framing frequency principle error of zero for framing record, and the maximum time resolving power of 8 ns and the scanning velocity nonuniformity of 0.136%~-0.277% for streak record. The test data have verified the performance of the camera quantitatively. This camera, simultaneously gained frames and streak with parallax-free and identical time base, is characterized by the plane optical system at oblique incidence different from space system, the innovative camera obscura without principle errors, and the high velocity motor driven beryllium-like rotating mirror, made of high strength aluminum alloy with cellular lateral structure. Experiments demonstrate that the camera is very useful and reliable to take high quality pictures of the detonation events.
Bioethics and the Framing of Climate Change's Health Risks.
Valles, Sean A
2015-06-01
Cheryl Cox Macpherson recently argued, in an article for this journal, that 'Climate Change is a Bioethics Problem'. This article elaborates on that position, particularly highlighting bioethicists' potential ability to help reframe the current climate change discourse to give more attention to its health risks. This reframing process is especially important because of the looming problem of climate change skepticism. Recent empirical evidence from science framing experiments indicates that the public reacts especially positively to climate change messages framed in public health terms, and bioethicists are particularly well positioned to contribute their expertise to the process of carefully developing and communicating such messages. Additionally, as climate framing research and practice continue, it will be important for bioethicists to contribute to the creation of that project's nascent ethical standards. The discourse surrounding antibiotic resistance is posited as an example that can lend insight into how communicating a public health-framed message, including the participation of bioethicists, can help to override public skepticism about the findings of politically contentious scientific fields. © 2014 John Wiley & Sons Ltd.
Idiopathic scoliosis instrumentation using the Lea Plaza sublaminar frame. A preliminary report.
Bauduin, G; Damas, A; Medina, J R; Dorantes, F
1997-01-01
We reviewed 28 patients with idiopathic scoliosis operated on using the segmental sublaminar instrumentation devised by Lea Plaza. The results at 2 years show that the spine is rebalanced and normal alignment in the sagittal plane is obtained. The biplanar correction of double curves averaged 64% with a loss of 10% at 2 years. The upper and lower limits of the fusion area must be determined accurately in relation to the pattern of the curve. Combined anterior and posterior arthrodesis is advised in flexible or rigid curves of more than 60 degrees in skeletally immature or mature patients respectively. In double curves over-correction of the primary curve behind its flexibility index, and inclusion of the mobile transitional segments in the fusion area produce decompensation in the frontal plane. One case of total loosening of the frame occurred, but there was no protrusion of the frame, no fractures of the laminae, no sepsis, no pseudarthrosis and no permanent neural damage.
Network-based H.264/AVC whole frame loss visibility model and frame dropping methods.
Chang, Yueh-Lun; Lin, Ting-Lan; Cosman, Pamela C
2012-08-01
We examine the visual effect of whole frame loss by different decoders. Whole frame losses are introduced in H.264/AVC compressed videos which are then decoded by two different decoders with different common concealment effects: frame copy and frame interpolation. The videos are seen by human observers who respond to each glitch they spot. We found that about 39% of whole frame losses of B frames are not observed by any of the subjects, and over 58% of the B frame losses are observed by 20% or fewer of the subjects. Using simple predictive features which can be calculated inside a network node with no access to the original video and no pixel level reconstruction of the frame, we developed models which can predict the visibility of whole B frame losses. The models are then used in a router to predict the visual impact of a frame loss and perform intelligent frame dropping to relieve network congestion. Dropping frames based on their visual scores proves superior to random dropping of B frames.
Rigid rod spaced fullerene as building block for nanoclusters
Indian Academy of Sciences (India)
By using phenylacetylene based rigid-rod linkers (PhA), we have successfully synthesized two fullerene derivatives, C60-PhA and C60-PhA-C60. The absorption spectral features of C60, as well as that of the phenylacetylene moiety are retained in the monomeric forms of these fullerene derivatives, ruling out the possibility ...
Study of rigidity of semiconducting vanadate glasses and its ...
Indian Academy of Sciences (India)
Administrator
to the increase in the molar volume and the role of different modifiers. These parameters along with the coor- dination number of the glasses affect the glass transition ... glass system (Kawamoto et al 1979, 1980; Music et al. 1994). The purpose of this study is to analyse quantitatively the elastic moduli and hence the rigidity ...
Rigid indented cylindrical cathode for X-ray tube
Hudgens, Claude R.
1985-01-01
A cathode assembly for a vacuum tube includes a wire filament, a straight bular anode parallel to and surrounding the wire filament, and insulating spacers for rigidly fastening the filament with respect to the anode, and with one side of the anode indented or flattened such that only one portion of the anode is heated to emitting temperatures by the filament.
Anti-synchronization of the rigid body exhibiting chaotic dynamics ...
African Journals Online (AJOL)
Based on a method derived from nonlinear control theory, we present a novel technical approach for synchronizing the dynamics of a rigid body exhibiting chaotic motion. In this framework, the active control technique is modified and employed to design control functions based on Lyapunov stability theory and ...
Static quark potential for a rigid string with constant density
International Nuclear Information System (INIS)
Zhou Xiaoan
1990-01-01
The static quark potential of a rigid string with constant density is calculated using a saddle point approximation. The 1/R dependence of the potential at large R is -π/6R, which agrees nicely with the analysis of Eichten et al. (-0.52/R). The universality of the coefficient of the 1/R term is discussed. (orig.)
Role of Rigid Endoscopic Detorsion in the Management of Sigmoid ...
African Journals Online (AJOL)
The ANNALS of AFRICAN SURGERY. July 2015 Volume 12 Issue 2. 85. ORIGINAL PAPER. Role of Rigid Endoscopic Detorsion in the. Management of Sigmoid Volvulus. Ngeno M, Ooko PB, Seno S, Oloo M, Topazian HM, White RE. Tenwek Hospital. Correspondence to: Dr. Mercy Ngeno, PO Box 39-20400, Bomet, Kenya.
Efficient Electroluminescence from a New Conjugated Rigid-Rod Polyquinoline
National Research Council Canada - National Science Library
Zhang, Xuejun, Ph.D
1998-01-01
A new conjugated rigid-rod polyquinoline, poly (2,2'-p-phenylene)-6,6'-bis(4-(p-tert-butylphenyl)quinoline)), was synthesized and its thin film was used as the emissive layer in light-emitting diodes...
Numerical rigid plastic modelling of shear capacity of keyed joints
DEFF Research Database (Denmark)
Herfelt, Morten Andersen; Poulsen, Peter Noe; Hoang, Linh Cao
2015-01-01
Keyed shear joints are currently designed using simple and conservative design formulas, yet these formulas do not take the local mechanisms in the concrete core of the joint into account. To investigate this phenomenon a rigid, perfectly plastic finite element model of keyed joints is used...
Dielectric relaxation phenomena of rigid polar liquid molecules ...
Indian Academy of Sciences (India)
journal of. October 2001 physics pp. 775–793. Dielectric relaxation phenomena of rigid polar liquid molecules under giga hertz electric field. K DUTTA, S K SIT and S ... BDH, England, n-hexane and n-heptane from M/s. E Merck ... used in medicine as drug to induce sleep and relieve pain and in the manufacture of D.D.T..
Study of rigidity of semiconducting vanadate glasses and its ...
Indian Academy of Sciences (India)
These parameters along with the coordination number of the glasses affect the glass transition temperature. The correlation between the elastic moduli and thermal properties of these samples showed that 0.25MoO3–0.25PbO–0.5V2O5 glass is the most rigid and has an applicable glass transition temperature for coating.
Dielectric relaxation phenomena of rigid polar liquid molecules ...
Indian Academy of Sciences (India)
The dielectric relaxation phenomena of rigid polar liquid molecules chloral and ethyltrichloroacetate () in benzene, -hexane and -heptane () under 4.2, 9.8 and 24.6 GHz electric ﬁelds at 30°C are studied to show the possible existence of double relaxation times 2 and 1 for rotations of the whole and the ﬂexible ...
Flexible (Polyactive®) versus rigid (hydroxyapatite) dental implants
Meijer, G.J.; Heethaar, J.; Cune, M.S.; de Putter, C.; van Blitterswijk, Clemens
1997-01-01
In a beagle dog study, the peri-implant bone changes around flexible (Polyactive®) and rigid hydroxyapatite (HA) implants were investigated radiographically by quantitative digital subtraction analysis and by assessment of marginal bone height, with the aid of a computerized method. A loss of
Influence of rigid boundary on the propagation of torsional surface ...
Indian Academy of Sciences (India)
Influence of rigid boundary on the propagation of torsional surface wave in an inhomogeneous layer. Shishir Gupta. ∗. , Rehena Sultana and Santimoy Kundu. Department of Applied Mathematics, Indian School of Mines, Dhanbad 826 004, India. ∗. Corresponding author. e-mail: shishir ism@yahoo.com. The present work ...
Controlling rigid formations of mobile agents under inconsistent measurements
Garcia de Marina Peinado, Hector; Cao, Ming; Jayawardhana, Bayu
2015-01-01
—Despite the great success of using gradient-based controllers to stabilize rigid formations of autonomous agents in the past years, surprising yet intriguing undesirable collective motions have been reported recently, when inconsistent measurements are used in the agents’ local controllers. To make
Rigidity theorem for Willmore surfaces in a sphere
Indian Academy of Sciences (India)
(Math. Sci.) Vol. 126, No. 2, May 2016, pp. 253–260. c Indian Academy of Sciences. Rigidity theorem for Willmore surfaces in a sphere. HONGWEI XU1 and DENGYUN YANG2,∗. 1Center of Mathematical Sciences, Zhejiang University, Hangzhou 310027,. People's Republic of China. 2College of Mathematics and ...
Short Communication: Statistical determination of the rigidity in ...
African Journals Online (AJOL)
From the graph of load against displacement, the rigidity in flexion at different moisture levels was determined from which the Young modulus was calculated. Linear regression models were fitted to the data and the results showed significant correlation coefficients between the Young modulus and moisture content for each ...
Impulsive and rigid temperament subtypes and executive functioning
African Journals Online (AJOL)
The aim of this study was to explore differences between the executive performance profiles in second order temperament trait configurations consisted of levels of harm avoidance (HA) and novelty seeking (NS). These trait configurations yield the impulsive temperament subtype (high NS and low HA) and the rigid ...
A survey on stability and rigidity results for Lie algebras
Crainic, Marius; Schätz, Florian; Struchiner, Ivan
2014-01-01
We give simple and unified proofs of the known stability and rigidity results for Lie algebras, Lie subalgebras and Lie algebra homomorphisms. Moreover, we investigate when a Lie algebra homomorphism is stable under all automorphisms of the codomain (including outer automorphisms).
"Mind the trap": mindfulness practice reduces cognitive rigidity.
Directory of Open Access Journals (Sweden)
Jonathan Greenberg
Full Text Available Two experiments examined the relation between mindfulness practice and cognitive rigidity by using a variation of the Einstellung water jar task. Participants were required to use three hypothetical jars to obtain a specific amount of water. Initial problems were solvable by the same complex formula, but in later problems ("critical" or "trap" problems solving was possible by an additional much simpler formula. A rigidity score was compiled through perseverance of the complex formula. In Experiment 1, experienced mindfulness meditators received significantly lower rigidity scores than non-meditators who had registered for their first meditation retreat. Similar results were obtained in randomized controlled Experiment 2 comparing non-meditators who underwent an eight meeting mindfulness program with a waiting list group. The authors conclude that mindfulness meditation reduces cognitive rigidity via the tendency to be "blinded" by experience. Results are discussed in light of the benefits of mindfulness practice regarding a reduced tendency to overlook novel and adaptive ways of responding due to past experience, both in and out of the clinical setting.
Knowledge-In-Action: An Example with Rigid Body Motion
Da Costa, Sayonara Salvador Cabral; Moreira, Marco Antonio
2005-01-01
This paper reports the analysis of the resolution of a paper-and-pencil problem, by eight undergraduate students majoring in engineering (six) and physics (two) at the Pontifcia Universidade Catlica do Rio Grande do Sul, in Porto Alegre, Brazil. The problem concerns kinetics of a rigid body, and the analysis was done in the light of Johnson-Lairds…
Vortex statistics for turbulence in a container with rigid boundaries
DEFF Research Database (Denmark)
Clercx, H.J.H.; Nielsen, A.H.
2000-01-01
The evolution of vortex statistics for decaying two-dimensional turbulence in a square container with rigid no-slip walls is compared with a few available experimental results and with the scaling theory of two-dimensional turbulent decay as proposed by Carnevale et al. Power-law exponents...
Viscoelastic materials with anisotropic rigid particles: stress-deformation behavior
Sagis, L.M.C.; Linden, van der E.
2001-01-01
In this paper we have derived constitutive equations for the stress tensor of a viscoelastic material with anisotropic rigid particles. We have assumed that the material has fading memory. The expressions are valid for slow and small deformations from equilibrium, and for systems that are nearly
Rigid sphere transport through a colloidal gas–liquid interface
de Folter, J.W.J.; de Villeneuve, V.W.A.; Aarts, D.G.A.L.; Lekkerkerker, H.N.W.
2010-01-01
In this paper we report on the gravity-driven transport of rigid spheres of various sizes through the fluid–fluid interface of a demixed colloid–polymer mixture. Three consecutive stages can be distinguished: (i) the sphere approaches the interface by sedimenting through the polymer-rich phase, (ii)
Rigidity and bradykinesia reduce interlimb coordination in Parkinsonian gait
Winogrodzka, Ania; Wagenaar, Robert C.; Booij, Jan; Wolters, Eric C.
2005-01-01
Objective: To assess the influence of rigidity and bradykinesia and the extent of dopaminergic degeneration on interlimb coordination during walking in early, drug-naive patients with Parkinson's disease (PD). Design: The interlimb coordination was examined during a systematic manipulation of
On the mechanism of gas transport in rigid polymer membranes
Hensema, E.R.; Hensema, E.R.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.
1993-01-01
Conventional polymers are compared as gas separation membrane materials with tailormade polymers. The increased permeability of the latter are due to their higher free volume available for gas transport. The increased free volume is associated with the rigidity polymer backbone. Free volume is
Flexibility versus rigidity in the practice of Islamic Family law
N.Y. Shehada (Nahda)
2009-01-01
textabstractThe last decades have witnessed a sustained critique of the mainstream Orientalist notion that classical Islamic family law was rigid, inflexible, and homogeneous. Many historians have used innovative methods to demonstrate that jurists and judges in precodification times enjoyed the
A Novel SFP Extracting/Tracking Framework for Rigid Microstructure Measurement
Directory of Open Access Journals (Sweden)
Sheng Liu
2012-01-01
Full Text Available 3D measurement and reconstruction of rigid microstructures rely on the precise matches of structural feature points (SFPs between microscopic images. However, most of the existing algorithms fail in extracting and tracking at microscale due to the poor quality of the microscopic images. This paper presents a novel framework for extracting and matching SFPs in microscopic images under two stereo microscopic imaging modes in our system, that is, fixed-positioning stereo and continuous-rotational stereo modes, respectively. A 4-DOF (degree of freedom micro visual measurement system is developed for 3D projective structural measurement of rigid microstructures using the SFPs obtained from microscopic images by the proposed framework. Under the fixed-positioning stereo mode, a similarity-pictorial structure algorithm is designed to preserve the illumination invariance in SFPs matching, while a method based on particle filter with affine transformation is developed for accurate tracking of multiple SFPs in image sequence under the continuous-rotational stereo mode. The experimental results demonstrate that the problems of visual distortion, illumination variability, and irregular motion estimation in micro visual measurement process can be effectively resolved by the proposed framework.
Rigid-flexible coupling dynamics of three-dimensional hub-beams system
International Nuclear Information System (INIS)
Liu Jinyang; Lu Hao
2007-01-01
In the previous research of the coupling dynamics of a hub-beam system, coupling between the rotational motion of hub and the torsion deformation of beam is not taken into account since the system undergoes planar motion. Due to the small longitudinal deformation, coupling between the rotational motion of hub and the longitudinal deformation of beam is also neglected. In this paper, rigid-flexible coupling dynamics is extended to a hub-beams system with three-dimensional large overall motion. Not only coupling between the large overall motion and the bending deformation, but also coupling between the large overall motion and the torsional deformation are taken into account. In case of temperature increase, the longitudinal deformation caused by the thermal expansion is significant, such that coupling between the large overall motion and the longitudinal deformation is also investigated. Combining the characteristics of the hybrid coordinate formulation and the absolute nodal coordinate formulation, the system generalized coordinates include the relative nodal displacement and the slope of each beam element with respect to the body-fixed frame of the hub, and the variables related to the spatial large overall motion of the hub and beams. Based on precise strain-displacement relation, the geometric stiffening effect is taken into account, and the rigid-flexible coupling dynamic equations are derived using velocity variational principle. Finite element method is employed for discretization. Simulation of a hub-beams system is used to show the coupling effect between the large overall motion and the torsional deformation as well as the longitudinal deformation. Furthermore, conservation of energy in case of free motion is shown to verify the formulation
International Nuclear Information System (INIS)
Jia, Zhenyong; Zhou, Qun; Li, Xiaowei; Fu, Yu; Ming, Hai; Zheng, Junwei
2015-01-01
Highlights: • Rigid porous framework of Li 4 Ti 5 O 12 microspheres can be fabricated by mutual molten growth of primary particles. • Well-confined nanosized tortuous channels are formed inside Li 4 Ti 5 O 12 microspheres. • Li 4 Ti 5 O 12 microspheres with rigid porous structures exhibit greatly enhanced electrochemical performance. - Abstract: Highly controllable porous architecture is desirable to tailor the physical and chemical properties of functional materials in advanced lithium ion batteries. Here, porous microspheres of spinel lithium titanate (Li 4 Ti 5 O 12 ), a promising alternative anode material for lithium ion batteries, are fabricated by mutual molten growth method in a controllable manner. The key role of the rigidity of the porous structure on the performance of the electrode materials in lithium ion batteries is demonstrated. Rigid framework of the materials is formed by second growth of the primary particles that fused together to generate an interconnected nanopore system inside the spheres, leading to better electrolyte diffusion and lower interparticle contact resistance, relative to the non-porous counterpart. The pristine Li 4 Ti 5 O 12 microspheres with uniform pore distribution and continuous framework exhibit high tap density, remarkable reversible capacity and rate capability, as well as excellent cycling stability. The present method is scalable and may provide a new approach to fabricate other candidate electrode materials for applications that require both high power and high volumetric energy density
Ortega, Michael; Redon, Stephane; Coquillart, Sabine
2007-01-01
This paper describes a generalization of the god-object method for haptic interaction between rigid bodies. Our approach separates the computation of the motion of the six degree-of-freedom god-object from the computation of the force applied to the user. The motion of the god-object is computed using continuous collision detection and constraint-based quasi-statics, which enables high-quality haptic interaction between contacting rigid bodies. The force applied to the user is computed using a novel constraint-based quasi-static approach, which allows us to suppress force artifacts typically found in previous methods. The constraint-based force applied to the user, which handles any number of simultaneous contact points, is computed within a few microseconds, while the update of the configuration of the rigid god-object is performed within a few milliseconds for rigid bodies containing up to tens of thousands of triangles. Our approach has been successfully tested on complex benchmarks. Our results show that the separation into asynchronous processes allows us to satisfy the different update rates required by the haptic and visual displays. Force shading and textures can be added and enlarge the range of haptic perception of a virtual environment. This paper is an extension of [1].
Initial Development of an Electronic Testis Rigidity Tester
Directory of Open Access Journals (Sweden)
Petros Mirilas
2011-01-01
Full Text Available We aimed to develop our previously presented mechanical device, the Testis Rigidity Tester (TRT, into an electronic system (Electronic Testis Rigidity Tester, ETRT by applying tactile imaging, which has been used successfully with other solid organs. A measuring device, located at the front end of the ETRT incorporates a tactile sensor comprising an array of microsensors. By application of a predetermined deformation of 2 mm, increased pressure alters linearly the resistance of each microsensor, producing changes of voltage. These signals were amplified, filtered, and digitized, and then processed by an electronic collector system, which presented them as a color-filled contour plot of the area of the testis coming into contact with the sensor. Testis models of different rigidity served for initial evaluation of ETRT; their evacuated central spaces contained different, increasing glue masses. An independent method of rigidity measurement, using an electric weight scale and a micrometer, showed that the more the glue injected, the greater the force needed for a 2-mm deformation. In a preliminary test, a single sensor connected to a multimeter showed similar force measurement for the same deformation in these phantoms. For each of the testis models compressed in the same manner, the ETRT system offered a map of pressures, represented by a color scale within the contour plot of the contact area with the sensor. ETRT found certain differences in rigidity between models that had escaped detection by a blind observer. ETRT is easy to use and provides a color-coded “insight“ of the testis internal structure. After experimental testing, it could be valuable in intraoperative evaluation of testes, so that the surgeon can decide about orchectomy or orcheopexy.
Matrix rigidity regulates cancer cell growth and cellular phenotype.
Directory of Open Access Journals (Sweden)
Robert W Tilghman
2010-09-01
Full Text Available The mechanical properties of the extracellular matrix have an important role in cell growth and differentiation. However, it is unclear as to what extent cancer cells respond to changes in the mechanical properties (rigidity/stiffness of the microenvironment and how this response varies among cancer cell lines.In this study we used a recently developed 96-well plate system that arrays extracellular matrix-conjugated polyacrylamide gels that increase in stiffness by at least 50-fold across the plate. This plate was used to determine how changes in the rigidity of the extracellular matrix modulate the biological properties of tumor cells. The cell lines tested fall into one of two categories based on their proliferation on substrates of differing stiffness: "rigidity dependent" (those which show an increase in cell growth as extracellular rigidity is increased, and "rigidity independent" (those which grow equally on both soft and stiff substrates. Cells which grew poorly on soft gels also showed decreased spreading and migration under these conditions. More importantly, seeding the cell lines into the lungs of nude mice revealed that the ability of cells to grow on soft gels in vitro correlated with their ability to grow in a soft tissue environment in vivo. The lung carcinoma line A549 responded to culture on soft gels by expressing the differentiated epithelial marker E-cadherin and decreasing the expression of the mesenchymal transcription factor Slug.These observations suggest that the mechanical properties of the matrix environment play a significant role in regulating the proliferation and the morphological properties of cancer cells. Further, the multiwell format of the soft-plate assay is a useful and effective adjunct to established 3-dimensional cell culture models.
Strategic rigidity and foresight for technology adoption among electric utilities
International Nuclear Information System (INIS)
Shah, Arsalan Nisar; Palacios, Miguel; Ruiz, Felipe
2013-01-01
The variation in the adoption of a technology as a major source of competitive advantage has been attributed to the wide-ranging strategic foresight and the integrative capability of a firm. These possible areas of competitive advantage can exist in the periphery of the firm's strategic vision and can get easily blurred as a result of rigidness and can permeate in the decision-making process of the firm. This article explores how electric utility firms with a renewable energy portfolio can become strategically rigid in terms of adoption of newer technologies. The reluctance or delay in the adoption of new technology can be characterized as strategic rigidness, brought upon as a result of a firm's core competence or core capability in the other, more conventional technology arrangement. This paper explores the implications of such rigidness on the performance of a firm and consequently on the energy eco-system. The paper substantiates the results by emphasizing the case of Iberdrola S.A., an incumbent firm as a wind energy developer and its adoption decision behavior. We illustrate that the very routines that create competitive advantage for firms in the electric utility industry are vulnerable as they might also develop as sources of competitive disadvantage, when firms confront environmental change and uncertainty. - Highlights: • Present a firm-level perspective on technology adoption behavior among electric utilities. • Firms with mature technology can become rigid towards newer technologies. • Case study analysis of a major electric utility firm. • Implications of ‘technology rigidness’ on the energy eco-system
Moving frames for heart fiber geometry
DEFF Research Database (Denmark)
Piuze, Emmanuel; Sporring, Jon; Siddiqi, Kaleem
2013-01-01
frames to study the rotations of a frame field attached to the local fiber direction. This approach provides a new set of parameters that are complimentary to those of Savadjiev et al. and offers a framework for developing new models of the cardiac fiber architecture. This framework is used to compute...
Time-framing and health risks: editorial
Brown, P.; Heyman, B.; Alaszewski, A.
2013-01-01
This special issue is the last in a four-part series Health Care Through the ‘Lens of Risk’, which focuses on risk categorisation, valuing, expecting and time-framing, respectively, and has been published in 2012-2013. The present editorial introduces the issue of time-framing in relation to an
Framing Behaviours in Novice Interaction Designers
Lotz, Nicole; Sharp, Helen; Woodroffe, Mark; Blyth, Richard; Rajah, Dino; Ranganai, Turugare
2015-01-01
Framing design problems and solutions has been recognised in design studies as a central designerly activity. Some recent findings with expert designers relate framing practices to problem-solution co-evolution and analogy use, two further widely recognised design strategies. We wanted to understand if interaction design novices also use…
A Framing Primer for Community College Leaders
Nausieda, Ryan
2014-01-01
The purpose of this article is to be a tool for community college leaders, as well as campus members, to positively and effectively utilize framing on their campuses. The fictional case of Maggie Pascal at Midwestern Community College illustrates the process of framing the change of a new partnership with Wind Energy Corporation to internal…
Teaching the Dynamics of Framing Competitions
Rinke, Eike Mark
2012-01-01
Framing theory is one of the most thriving and complex fields of communication theory, and as such it has grown to be an integral part of many political communication, public opinion, and communication theory courses. Part of the complexity stems from scholars' efforts to develop accounts of framing processes that are closer to the "real world" of…
Sustainable food and agriculture: stakeholder's frames
van Gorp, B.; van der Goot, M.J.
2012-01-01
Despite its importance, the notion of sustainability is open for discursive struggle. This article's primary objective is to acquire insight into the manner in which the principal stakeholders strategically use frames in their public communication about sustainable food and agriculture. A framing
An introduction to frames and Riesz bases
Christensen, Ole
2016-01-01
This revised and expanded monograph presents the general theory for frames and Riesz bases in Hilbert spaces as well as its concrete realizations within Gabor analysis, wavelet analysis, and generalized shift-invariant systems. Compared with the first edition, more emphasis is put on explicit constructions with attractive properties. Based on the exiting development of frame theory over the last decade, this second edition now includes new sections on the rapidly growing fields of LCA groups, generalized shift-invariant systems, duality theory for as well Gabor frames as wavelet frames, and open problems in the field. Key features include: *Elementary introduction to frame theory in finite-dimensional spaces * Basic results presented in an accessible way for both pure and applied mathematicians * Extensive exercises make the work suitable as a textbook for use in graduate courses * Full proofs includ ed in introductory chapters; only basic knowledge of functional analysis required * Explicit constructi...
PAIR FRAMES IN HILBERT C∗−MODULES 1. Introduction Frames ...
Indian Academy of Sciences (India)
53
and sufficient conditions for a Hilbert C∗−module to admit a pair frame with a symbol and two standard Bessel sequences. Moreover by generalizing some of the results obtained for Bessel multipliers in Hilbert C∗−modules to pair frames and considering the stability of pair frames under invertible operators, we construct.
Karaton, Muhammet
2014-01-01
A beam-column element based on the Euler-Bernoulli beam theory is researched for nonlinear dynamic analysis of reinforced concrete (RC) structural element. Stiffness matrix of this element is obtained by using rigidity method. A solution technique that included nonlinear dynamic substructure procedure is developed for dynamic analyses of RC frames. A predicted-corrected form of the Bossak-α method is applied for dynamic integration scheme. A comparison of experimental data of a RC column element with numerical results, obtained from proposed solution technique, is studied for verification the numerical solutions. Furthermore, nonlinear cyclic analysis results of a portal reinforced concrete frame are achieved for comparing the proposed solution technique with Fibre element, based on flexibility method. However, seismic damage analyses of an 8-story RC frame structure with soft-story are investigated for cases of lumped/distributed mass and load. Damage region, propagation, and intensities according to both approaches are researched.
Directory of Open Access Journals (Sweden)
Muhammet Karaton
2014-01-01
Full Text Available A beam-column element based on the Euler-Bernoulli beam theory is researched for nonlinear dynamic analysis of reinforced concrete (RC structural element. Stiffness matrix of this element is obtained by using rigidity method. A solution technique that included nonlinear dynamic substructure procedure is developed for dynamic analyses of RC frames. A predicted-corrected form of the Bossak-α method is applied for dynamic integration scheme. A comparison of experimental data of a RC column element with numerical results, obtained from proposed solution technique, is studied for verification the numerical solutions. Furthermore, nonlinear cyclic analysis results of a portal reinforced concrete frame are achieved for comparing the proposed solution technique with Fibre element, based on flexibility method. However, seismic damage analyses of an 8-story RC frame structure with soft-story are investigated for cases of lumped/distributed mass and load. Damage region, propagation, and intensities according to both approaches are researched.
ANALISIS FRAMING BERITA TAWURAN ANTAR PELAJAR DI HARIAN KOMPAS
Directory of Open Access Journals (Sweden)
Sri Widowati Herieningsih
2016-02-01
Full Text Available Student brawls occur continuously in various cities, especially in the Jakarta, the attention of many people, and did not escape the attention of the media. Framing Kompas is a mayor concern in this study. The study conducted by taking a sample 0f 37 news, between 2008 to 2012. The paradigm used is the paradigm of constructivism. The method used is the analysis of the model Entman framing.The results that the Kompas student brawls see that the problem is complexs issue, and not ordinary deliguency, but it leads to crime, a form of deviance. Student brawls, agroup behavior, and other problems caused by unclear, revenge hereditary, in solidarity with friends, as well as maintain the good name of the school, violence derived from the senior students to yunior. Recommendation are offfered to prevent and fight is, sanction, both preventive and repressive, conducted formal and nonformal.
Rigid motion correction of dual opposed planar projections in single photon imaging
Angelis, G. I.; Ryder, W. J.; Gillam, J. E.; Boisson, F.; Kyme, A. Z.; Fulton, R. R.; Meikle, S. R.; Kench, P. L.
2017-05-01
Awake and/or freely moving small animal single photon emission imaging allows the continuous study of molecules exhibiting slow kinetics without the need to restrain or anaesthetise the animals. Estimating motion free projections in freely moving small animal planar imaging can be considered as a limited angle tomography problem, except that we wish to estimate the 2D planar projections rather than the 3D volume, where the angular sampling in all three axes depends on the rotational motion of the animal. In this study, we hypothesise that the motion corrected planar projections estimated by reconstructing an estimate of the 3D volume using an iterative motion compensating reconstruction algorithm and integrating it along the projection path, will closely match the true, motion-less, planar distribution regardless of the object motion. We tested this hypothesis for the case of rigid motion using Monte-Carlo simulations and experimental phantom data based on a dual opposed detector system, where object motion was modelled with 6 degrees of freedom. In addition, we investigated the quantitative accuracy of the regional activity extracted from the geometric mean of opposing motion corrected planar projections. Results showed that it is feasible to estimate qualitatively accurate motion-corrected projections for a wide range of motions around all 3 axes. Errors in the geometric mean estimates of regional activity were relatively small and within 10% of expected true values. In addition, quantitative regional errors were dependent on the observed motion, as well as on the surrounding activity of overlapping organs. We conclude that both qualitatively and quantitatively accurate motion-free projections of the tracer distribution in a rigidly moving object can be estimated from dual opposed detectors using a correction approach within an iterative reconstruction framework and we expect this approach can be extended to the case of non-rigid motion.
International Nuclear Information System (INIS)
Breunhoelder, Gert
2002-01-01
This presentation deals with the following keypoints: Information Technology (IT) Business Continuity and Recovery essential for any business; lessons learned after Sept. 11 event; Detailed planning, redundancy and testing being the key elements for probability estimation of disasters
The welded CNC machine tool frame
Directory of Open Access Journals (Sweden)
Boral Piotr
2018-01-01
Full Text Available Machine tools are built based on cast-iron bodies. Cast iron well dumps down vibrations and is dimensionally stable. Therefore, many conventional machine tools are modernized and modified into CNC machine tools based on the seasoned old bodies of those machine tools. Nevertheless, CNC machine tools are also manufactured based on polymer concrete, which vibration damping ability is even better. On the other hand, attempts made in the past by leading machine tool manufacturers to use welded frames in CNC machine tools failed. The revival of interest in welded frames was spurred by economic considerations, as steel systems are much thinner compared to cast-iron ones. They are able to carry the same loads. The construction of CNC machine tools with a welded steel frame undertaken at the Institute of Mechanical Technologies (ITM of the Czestochowa University of Technology is an attempt to solve this constructional problem. The machine tool frame was designed with use of CAD solid works system. The ultimate success of using the welded frame is determined not only by the frame itself, but also generally the design of the machine tool and its operation parameters. The welded frame was used for a high-accuracy three-axis milling machine. In this respect, it is equal of professional machine tools manufactured by reputed companies. It can be either a production machine tool or a test stand.
International Nuclear Information System (INIS)
Peng, Y.K.M.
1978-04-01
A tokamak configuration is proposed that permits the rapid replacement of a plasma discharge in a ''burn'' chamber by another one in a time scale much shorter than the elementary thermal time constant of the chamber first wall. With respect to the chamber, the effective duty cycle factor can thus be made arbitrarily close to unity minimizing the cyclic thermal stress in the first wall. At least one plasma discharge always exists in the new tokamak configuration, hence, a continuous tokamak. By incorporating adiabatic toroidal compression, configurations of continuous tokamak compressors are introduced. To operate continuous tokamaks, it is necessary to introduce the concept of mixed poloidal field coils, which spatially groups all the poloidal field coils into three sets, all contributing simultaneously to inducing the plasma current and maintaining the proper plasma shape and position. Preliminary numerical calculations of axisymmetric MHD equilibria in continuous tokamaks indicate the feasibility of their continued plasma operation. Advanced concepts of continuous tokamaks to reduce the topological complexity and to allow the burn plasma aspect ratio to decrease for increased beta are then suggested
Makhrojan, Agus; Suprihadi, Agus; Budi, Sigit Setijo; Jamari, J.; Ismail, Rifky
2017-01-01
The electric car is transportation which growing and constantly put through improvisation vehicle design. One of the structural components of the electric car which holds a major role is a frame. The purpose of this study is to get monocoque frame design which lightweight and powerful for a city car with two passengers that was able to improve the efficiency of the battery voltage source. Monocoque frame should be able to accept the normal loads such as the weight of batteries, passenger, and body. The most important thing, monocoque frame should also be able to protect the driver and passengers in the event of a collision. Mild steel was chosen for the design because it is easy to obtain and reasonable price as well as easy to shaped for two-seater electric car. FEM (finite element method) was used to determine stress determination and rigidity of the monocoque frame when receiving a static load. The results show that the monocoque frame was still able to withstand the required loads with minimal deflection.
A FRAMING OF FUTURE EUROPEAN PARLIAMENT ELECTIONS 2014 IN A SOCIAL MEDIA CONTEXT
Directory of Open Access Journals (Sweden)
Dorian Pocovnicu
2013-12-01
Full Text Available Communication in marketing has always been a continuous conceptual hybrid of input from various domains: marketing, P.R., communication, sociology. With the constant transformation of web 2.0. phenomenon, the demarcation lines between these domains and their influence has become more blured and difficult to pinpoint. As a result, specific research methods and theories have become adaptable instruments, laying the path for grounded theory approaches or new research methods. Framing theory, having as basis that the media focuses attention on certain events and then places them within a field of meaning, has shifted towards organisations, and further on, to institutions. Framing is a quality of communication that leads others to accept one meaning over another. Framing theory suggests that how something is presented (the “frame” influences the choices people make. In online communicative contexts, their own personal framings allows the communicative actors to make use of language and forethought so that specific embodiments of future evolutions may be depicted. In our case, we shall focus on the topic: European Parliament elections, which are to take place in 2014, and on the manner in which it has been framed in two online chat session with three MEPs. It is our intention to identify the framing techniques used, the framing links and the framing alignments.
Journalism Curiosity and Story Telling Frame
DEFF Research Database (Denmark)
Grunwald, Ebbe; Rupar, Verica
2009-01-01
which helps to define what is known of a topic. Using the newspaper coverage of the events following the discovery of a ‘mysterious sickness' in the previous home of a group of Tasmanian devils sent to Copenhagen Zoo as a christening gift for the baby of the Danish royal, the article examines how...... the epistemological and organisational dimension of frames relates to the process of meaning-making. We suggest refining the concept of frame in journalism studies by making a distinction between a frame (an epistemological category) and an angle (a textual organisation category). Our investigation shows...
Framing of regimes and transition strategies
DEFF Research Database (Denmark)
Jensen, Jens Stissing
2012-01-01
This article suggests that transition strategies are always formulated in the context of specific representations of the regime and the challenges it faces. It is argued that the framing of a regime affects the envisioning of transition strategies. An analysis of the current development agenda fo...... for the housing construction sector in Denmark reveals the relevance and impacts of different regime framings. It is proposed that the ability to cope with framing issues as situated and political processes is at the core of the governance of transitions....
Rigidity of complete noncompact bach-flat n-manifolds
Chu, Yawei; Feng, Pinghua
2012-11-01
Let (Mn,g) be a complete noncompact Bach-flat n-manifold with the positive Yamabe constant and constant scalar curvature. Assume that the L2-norm of the trace-free Riemannian curvature tensor R∘m is finite. In this paper, we prove that (Mn,g) is a constant curvature space if the L-norm of R∘m is sufficiently small. Moreover, we get a gap theorem for (Mn,g) with positive scalar curvature. This can be viewed as a generalization of our earlier results of 4-dimensional Bach-flat manifolds with constant scalar curvature R≥0 [Y.W. Chu, A rigidity theorem for complete noncompact Bach-flat manifolds, J. Geom. Phys. 61 (2011) 516-521]. Furthermore, when n>9, we derive a rigidity result for R<0.
Rigid inclusions-Comparison between analytical and numerical methods
International Nuclear Information System (INIS)
Gomez Perez, R.; Melentijevic, S.
2014-01-01
This paper compares different analytical methods for analysis of rigid inclusions with finite element modeling. First of all, the load transfer in the distribution layer is analyzed for its different thicknesses and different inclusion grids to define the range between results obtained by analytical and numerical methods. The interaction between the soft soil and the inclusion in the estimation of settlements is studied as well. Considering different stiffness of the soft soil, settlements obtained analytical and numerically are compared. The influence of the soft soil modulus of elasticity on the neutral point depth was also performed by finite elements. This depth has a great importance for the definition of the total length of rigid inclusion. (Author)
MRS2016: Rigid Moon Rotation Series in the Relativistic Approximation
Pashkevich, V. V.
2017-03-01
The rigid Moon rotation problem is studied for the relativistic (kinematical) case, in which the geodetic perturbations in the Moon rotation are taken into account. As the result of this research the high-precision Moon Rotation Series MRS2016 in the relativistic approximation was constructed for the first time and the discrepancies between the high-precision numerical and the semi-analytical solutions of the rigid Moon rotation were investigated with respect to the fixed ecliptic of epoch J2000, by the numerical and analytical methods. The residuals between the numerical solution and MRS2016 in the perturbing terms of the physical librations do not exceed 80 mas and 10 arc seconds over 2000 and 6000 years, respectively.
Rigid-plastic seismic design of reinforced concrete structures
DEFF Research Database (Denmark)
Costa, Joao Domingues; Bento, R.; Levtchitch, V.
2007-01-01
In this paper a new seismic design procedure for Reinforced Concrete (R/C) structures is proposed-the Rigid-Plastic Seismic Design (RPSD) method. This is a design procedure based on Non-Linear Time-History Analysis (NLTHA) for systems expected to perform in the non-linear range during a lifetime...... earthquake event. The theoretical background is the Theory of Plasticity (Rigid-Plastic Structures). Firstly, a collapse mechanism is chosen and the corresponding stress field is made safe outside the regions where plastic behaviour takes place. It is shown that this allows the determination of the required...... required strength throughout the structure. Any artificial considerations intended to adjust results according to empirical observations are avoided, which, from a conceptual point of view, is considered to be an advantage over other simplified design procedures for seismic design. The procedure...
Nonlinear Receding-Horizon Control of Rigid Link Robot Manipulators
Directory of Open Access Journals (Sweden)
R. Hedjar
2005-03-01
Full Text Available The approximate nonlinear receding-horizon control law is used to treat the trajectory tracking control problem of rigid link robot manipulators. The derived nonlinear predictive law uses a quadratic performance index of the predicted tracking error and the predicted control effort. A key feature of this control law is that, for their implementation, there is no need to perform an online optimization, and asymptotic tracking of smooth reference trajectories is guaranteed. It is shown that this controller achieves the positions tracking objectives via link position measurements. The stability convergence of the output tracking error to the origin is proved. To enhance the robustness of the closed loop system with respect to payload uncertainties and viscous friction, an integral action is introduced in the loop. A nonlinear observer is used to estimate velocity. Simulation results for a two-link rigid robot are performed to validate the performance of the proposed controller.
Nonlinear Receding-Horizon Control of Rigid Link Robot Manipulators
Directory of Open Access Journals (Sweden)
R. Hedjar
2008-11-01
Full Text Available The approximate nonlinear receding-horizon control law is used to treat the trajectory tracking control problem of rigid link robot manipulators. The derived nonlinear predictive law uses a quadratic performance index of the predicted tracking error and the predicted control effort. A key feature of this control law is that, for their implementation, there is no need to perform an online optimization, and asymptotic tracking of smooth reference trajectories is guaranteed. It is shown that this controller achieves the positions tracking objectives via link position measurements. The stability convergence of the output tracking error to the origin is proved. To enhance the robustness of the closed loop system with respect to payload uncertainties and viscous friction, an integral action is introduced in the loop. A nonlinear observer is used to estimate velocity. Simulation results for a two-link rigid robot are performed to validate the performance of the proposed controller.
One-DOF Superimposed Rigid Origami with Multiple States.
Liu, Xiang; Gattas, Joseph M; Chen, Yan
2016-11-10
Origami-inspired engineering design is increasingly used in the development of self-folding structures. The majority of existing self-folding structures either use a bespoke crease pattern to form a single structure, or a universal crease pattern capable of forming numerous structures with multiple folding steps. This paper presents a new approach whereby multiple distinct, rigid-foldable crease patterns are superimposed in the same sheet such that kinematic independence and 1-DOF mobility of each individual pattern is preserved. This is enabled by the cross-crease vertex, a special configuration consisting of two pairs of collinear crease lines, which is proven here by means of a kinematic analysis to contain two independent 1-DOF rigid-foldable states. This enables many new origami-inspired engineering design possibilities, with two explored in depth: the compact folding of non-flat-foldable structures and sequent folding origami that can transform between multiple states without unfolding.
Steady fall of a rigid body in viscous fluid
Czech Academy of Sciences Publication Activity Database
Nečasová, Šárka
2005-01-01
Roč. 63, Sp. Is. (2005), s. 2113-2119 ISSN 0362-546X. [Invited Talks from the Fourth World Congress of Nonlinear Analysts (WCNA 2004). Orlando , 30.7.2004-7.8.2004] R&D Projects: GA ČR(CZ) GA201/02/0684 Institutional research plan: CEZ:AV0Z1019905 Keywords : steady fall * rigid body * viscous fluid Subject RIV: BA - General Mathematics Impact factor: 0.519, year: 2005
NOLB: Nonlinear Rigid Block Normal Mode Analysis Method
Hoffmann , Alexandre; Grudinin , Sergei
2017-01-01
International audience; We present a new conceptually simple and computationally efficient method for nonlinear normal mode analysis called NOLB. It relies on the rotations-translations of blocks (RTB) theoretical basis developed by Y.-H. Sanejouand and colleagues. We demonstrate how to physically interpret the eigenvalues computed in the RTB basis in terms of angular and linear velocities applied to the rigid blocks and how to construct a nonlinear extrapolation of motion out of these veloci...
Dielectric relaxation phenomena of rigid polar liquid molecules ...
Indian Academy of Sciences (India)
Abstract. The dielectric relaxation phenomena of rigid polar liquid molecules chloral and ethyl- trichloroacetate (j) in benzene, n-hexane and n-heptane (i) under 4.2, 9.8 and 24.6 GHz electric fields at 30ÆC are studied to show the possible existence of double relaxation times τ2 and τ1 for rotations of the whole and the ...
Nonlinear dynamics mathematical models for rigid bodies with a liquid
Lukovsky, Ivan A
2015-01-01
This book is devoted to analytically approximate methods in the nonlinear dynamics of a rigid body with cavities partly filled by liquid. It combines several methods and compares the results with experimental data. It is useful for experienced and early-stage readers interested in analytical approaches to fluid-structure interaction problems, the fundamental mathematical background and modeling the dynamics of such complex mechanical systems.
On Polya's inequality for torsional rigidity and first Dirichlet eigenvalue
Berg, M. van den; Ferone, V.; Nitsch, C.; Trombetti, C.
2016-01-01
Let $\\Omega$ be an open set in Euclidean space with finite Lebesgue measure $|\\Omega|$. We obtain some properties of the set function $F:\\Omega\\mapsto \\R^+$ defined by $$ F(\\Omega)=\\frac{T(\\Omega)\\lambda_1(\\Omega)}{|\\Omega|} ,$$ where $T(\\Omega)$ and $\\lambda_1(\\Omega)$ are the torsional rigidity and the first eigenvalue of the Dirichlet Laplacian respectively. We improve the classical P\\'olya bound $F(\\Omega)\\le 1,$ and show that $$F(\\Omega)\\le 1- \
Shape Optimization of Revolute-Jointed Rigid-Flexible Manipulator
Mahto, S.; Dixit, U. S.
2014-10-01
This work illustrates the shape optimization of flexible link of revolute-jointed rigid-flexible manipulator. Flexible link is considered as Euler-Bernoulli beam and dynamic analysis is carried out by finite element based on Langrange approach. Nonlinear classical search technique (Sequential Quadratic Programming method) is applied to extremize the four different objectives. Different optimized shapes are obtained for different optimization problems. Optimized shapes improve the static and dynamic response of the system viz. fundamental frequency, hub angles, flexural vibration, etc.
Direct vision bladder catheterization using a short rigid ureteroscope.
Rozanski, T A; Salazar, F; Thompson, I M
1998-05-01
We describe the use of a short, rigid ureteroscope to place a Foley catheter into the bladder under direct vision. The Circon ACMI MICRO-6 short ureteroscope was passed through a 22F Foley catheter modified with a catheter punch device. The catheter was placed rapidly and without difficulty in 2 patients with significant undermining of the trigone after transurethral incision of the prostate. This technique is rapid, simple, and avoids the potential complications of blind catheter placement following difficult transurethral procedures.
Sicily in its Mediterranean geological frame
Energy Technology Data Exchange (ETDEWEB)
Broquet, P.
2016-10-01
The Island of Sicily is generally considered to be the geological link between the North African Fold Belt and the Appennines, in Italy. This comes from a cylindristic meaning and is only partly exact. As a matter of fact, Sicily is essentially Greek; Ionian. Up to Middle Cretaceous time, the Sicilian area was a submerged shoal in the sea or the Panormide area, bordering the Ionian Ocean. This shoal lay between the future North African Fold Belt and the Appennines, forming an intermediate link between the Appenninic, Apulian, Panormian and Tunisian platforms. It was only during the Middle to Upper Cretaceous that the Atlantic and Ligure Oceans merged, making a continuous relationship between the Appenninic, Sicilian and North African sedimentary series. The key time periods are the Permian, Cretaceous and Oligo-Miocene periods leading to the formation of the actual Calabro-Sicilian arc. From the Permian to the present, the Sicilian geological history pertains to three oceanic domains: Ionian, Ligurian and Atlantic, of which the Ionian and Ligurian were under the influence of Tethys (Neo and Paleo-Tethys). The Tethysian identity of Sicily constitutes the major aspect of its geological history. However, the European and African plate tectonic movements complicated its structure. During the Middle Miocene subduction, southern Sicily became African, meanwhile its north-eastern part became, in Pliocene time, Maghrebian by accretion. Sicily is thus a truly geological patchwork, but its main section remains Ionian and now constitutes a link between North Africa and the Appennines. With older data, but also by means of recent results, we will replace Sicily in its Mediterranean frame, giving the mean stages of its paleogeographical and then its tectonic evolution. We will review the calabro-sicilian arc evolution from the Oligocene, developing the actual context and recalling the main fundamental play of the Numidian flysch. (Author)
Chiral Orientation of Skeletal Muscle Cells Requires Rigid Substrate
Directory of Open Access Journals (Sweden)
Ninghao Zhu
2017-06-01
Full Text Available Reconstitution of tissue morphology with inherent left–right (LR asymmetry is essential for tissue/organ functions. For skeletal muscle, the largest tissue in mammalian organisms, successful myogenesis requires the regulation of the LR asymmetry to form the appropriate muscle alignment. However, the key factor for reproducing the LR asymmetry of skeletal tissues in a controllable, engineering context remains largely unknown. Recent reports indicate that cell chirality may underlie the LR development in tissue morphogenesis. Here, we report that a rigid substrate is required for the chirality of skeletal muscle cells. By using alternating micropatterned cell-adherent and cell-repellent stripes on a rigid substrate, we found that C2C12 skeletal muscle myoblasts exhibited a unidirectional tilted orientation with respect to the stripe boundary. Importantly, such chiral orientation was reduced when soft substrates were used instead. In addition, we demonstrated the key role of actin stress fibers in the formation of the chiral orientation. This study reveals that a rigid substrate is required for the chiral pattern of myoblasts, paving the way for reconstructing damaged muscle tissue with inherent LR asymmetry in the future.
Field dependent cosmic ray streaming at high rigidities
International Nuclear Information System (INIS)
Swinson, D.B.
1976-01-01
Data from underground μ meson telescopes at depths of 25, 40, and 80 mwe covering the period 1965--1973 have been analyzed as a function of interplanetary magnetic field direction. Cosmic ray streaming both in and perpendicular to the ecliptic plane, with directions dependent on the sense of the interplanetary magnetic field, is observed throughout the period at all depths. The field dependent streaming in the ecliptic plane exhibits some variability in amplitude and phase but contains a component in the direction perpendicular to the interplanetary magnetic field direction which is consistent with B x delN streaming due to a perpendicular cosmic ray density gradient pointing southward (higher density below the ecliptic plane than above it). In the case of the field dependent streaming perpendicular to the ecliptic plane the direction of the streaming has remained remarkably consistent over the 9-year period. One possible source of this streaming is B x delN streaming due to a radial heliocentric cosmic ray density gradient; this possibility is discussed along with other possible sources. There does not appear to be an obvious variation in the amplitude of the field dependent streaming either in or perpendicular to the ecliptic plane with increasing rigidity; both effects are still apparent at rigidities well above the 52-GV threshold rigidity of the Socorro 80-mwe telescope. The amplitudes of both anisotropies appear larger at solar maximum than at solar minimum
Integrable Problems of the Dynamics of Coupled Rigid Bodies
Bogoyavlenskiĭ, O. I.
1993-06-01
Several classical problems of dynamics are shown to be integrable for the special systems of coupled rigid bodies introduced in this paper and called Ck-central configurations. It is proved that the dynamics of an arbitrary Ck-central configuration in the Newtonian gravitational field with an arbitrary quadratic potential is integrable in the Liouville sense and in theta-functions of Riemann surfaces. A hidden symmetry of the inertial dynamics of these configurations is found, and reductions of the corresponding Lagrange equations to the Euler equations on the direct sums of Lie coalgebras SO(3) are obtained. Reductions and integrable cases of the equations for the rotation of a heavy Ck-central configuration about a fixed point are indicated. Separation of rotations of a space station type orbiting system, which is a Ck-central configuration of rigid bodies, is proved. This result leads to the possibility of independent stabilization of rotations of the rigid bodies in such orbiting configurations. Integrability of the inertial dynamics of CRn-central configurations of coupled gyrostats is proved.
Green waste cooking oil-based rigid polyurethane foam
Enderus, N. F.; Tahir, S. M.
2017-11-01
Polyurethane is a versatile polymer traditionally prepared using petroleum-based raw material. Petroleum, however, is a non-renewable material and polyurethane produced was found to be non-biodegradable. In quest for a more environmentally friendly alternative, wastecooking oil, a highly abundant domestic waste with easily derivatized structure, is a viable candidate to replace petroleum. In this study,an investigation to determine physical and chemical properties of rigid polyurethane (PU) foam from waste cooking oil (WCO) was carried out. WCO was first adsorbed by using coconut husk activated carbon adsorbent prior to be used for polyol synthesis. The purified WCO was then used to synthesize polyol via transesterification reaction to yield alcohol groups in the WCO chains structure. Finally, the WCO-based polyol was used to prepare rigid PU foam. The optimum formulation for PU formation was found to be 90 polyol: 60 glycerol: 54 water: 40 diethanolamine: 23 diisocyanate. The rigid PU foam has density of 208.4 kg/m3 with maximum compressive strength and capability to receive load at 0.03 MPa and 0.09 kN, respectively. WCO-based PU can potentially be used to replace petroleum-based PU as house construction materials such as insulation panels.
LENUS (Irish Health Repository)
Ahmad, Nasir Zaheer
2012-06-01
Rigid sigmoidoscopy is sometimes performed at first presentation in colorectal clinics. We assessed the feasibility of flexible sigmoidoscopy in similar situations by comparing it with rigid sigmoidoscopy as a first investigative tool.
Towards Sub-Microarsecond Rigid Earth Nutation Series in the Hamiltonian Theory
National Research Council Canada - National Science Library
Souchay, Jean; Folgueira, M
2000-01-01
...) are based on the works of Kinoshita (1977) and Wahr (1979). In Kinoshita's work, the rigid Earth nutation series were calculated by the application of the Hamiltonian canonical equations to the rotation of the rigid and elliptical Earth...
Nucleosome–nucleosome interactions via histone tails and linker DNA regulate nuclear rigidity
Shimamoto, Yuta; Tamura, Sachiko; Masumoto, Hiroshi; Maeshima, Kazuhiro
2017-01-01
Cells, as well as the nuclei inside them, experience significant mechanical stress in diverse biological processes, including contraction, migration, and adhesion. The structural stability of nuclei must therefore be maintained in order to protect genome integrity. Despite extensive knowledge on nuclear architecture and components, however, the underlying physical and molecular mechanisms remain largely unknown. We address this by subjecting isolated human cell nuclei to microneedle-based quantitative micromanipulation with a series of biochemical perturbations of the chromatin. We find that the mechanical rigidity of nuclei depends on the continuity of the nucleosomal fiber and interactions between nucleosomes. Disrupting these chromatin features by varying cation concentration, acetylating histone tails, or digesting linker DNA results in loss of nuclear rigidity. In contrast, the levels of key chromatin assembly factors, including cohesin, condensin II, and CTCF, and a major nuclear envelope protein, lamin, are unaffected. Together with in situ evidence using living cells and a simple mechanical model, our findings reveal a chromatin-based regulation of the nuclear mechanical response and provide insight into the significance of local and global chromatin structures, such as those associated with interdigitated or melted nucleosomal fibers. PMID:28428255
Gabor frames by sampling and periodization
DEFF Research Database (Denmark)
Søndergaard, Peter Lempel
2007-01-01
By sampling the window of Gabor frame for L-2 (R) belonging to Feichtingers algebra S-0 (R), one obtains a Gabor frame for l(2) (Z). In this article we present a survey of results by R. Orr and A.J.E.M. Janssen and extend their ideas to cover interrelations among Gabor frames for the four spaces L......-2 (R), l(2) (Z), L-2 ([O,L]) and C-L. Some new results about the general dual windows with respect to sampling and periodization are presented as well. This theory is used to show a new result of the Kaiblinger type to construct an approximation to the canonical dual window of a Gabor frame for L-2...
News Media Framing of Negative Campaigning
DEFF Research Database (Denmark)
Pedersen, Rasmus Tue
2014-01-01
News media coverage of election campaigns is often characterized by use of the strategic game frame and a focus on politicians’ use of negative campaigning. However, the exact relationship between these two characteristics of news coverage is largely unexplored. This article theorizes that consumer...... demand and norms of journalistic independence might induce the news media outlets to cover negative campaigning with a strategic game frame. A comprehensive content analysis based on several newspaper types, several election campaigns, and several different measurements of media framing confirms...... that news coverage of negative campaigning does apply the strategic game frame to a significantly larger degree than articles covering positive campaigning. This finding has significant implications for campaigning politicians and for scholars studying campaign and media effects....
The characteristics of a successful framing process
DEFF Research Database (Denmark)
Haase, Louise Møller
2017-01-01
In design schools and university we need to teach students how to frame their projects in ways that create a significant and new perspective on the problem situation as well as clear direction for the solution. We teach students how to engage in user research, prototyping, conceptualization...... every day during the development of a conceptual design. This study indicated a significant difference between the high-grade students and the low-grade students both when it came to how they formulated the frame, how they revised the frame, their research strategy, their documentation as well......, business and technology analysis, but often the ability to take information from these different processes and add it together, into a new way of solving the wicked problem, is left for the student to figure out either in a supervised or unsupervised process. Previous research in the framing process has...
Approximation of the inverse G-frame operator
Indian Academy of Sciences (India)
In this paper, we introduce the concept of (strong) projection method for -frames which works for all conditional -Riesz frames. We also derive a method for approximation of the inverse -frame operator which is efficient for all -frames. We show how the inverse of -frame operator can be approximated as close as we ...
Approximation of the inverse G-frame operator
Indian Academy of Sciences (India)
... projection method for -frames which works for all conditional -Riesz frames. We also derive a method for approximation of the inverse -frame operator which is efficient for all -frames. We show how the inverse of -frame operator can be approximated as close as we like using finite-dimensional linear algebra.
Figurative framing : Shaping public discourse through metaphor, hyperbole and irony
Burgers, C.; Konijn, E.A.; Steen, G.J.
2016-01-01
Framing is an important concept in communication, yet many framing studies set out to develop frames relevant to only one issue. We expand framing theory by introducing figurative framing. We posit that figurative language types like metaphor, hyperbole and irony are important in shaping public
Figurative framing: Shaping public discourse through metaphor, hyperbole and irony
Burgers, C.F.; Konijn, E.A.; Steen, G.J.
2016-01-01
Framing is an important concept in communication, yet many framing studies set out to develop frames relevant to only one issue. We expand framing theory by introducing figurative framing. We posit that figurative language types like metaphor, hyperbole and irony are important in shaping public
High Performance Commercial Fenestration Framing Systems
Energy Technology Data Exchange (ETDEWEB)
Mike Manteghi; Sneh Kumar; Joshua Early; Bhaskar Adusumalli
2010-01-31
A major objective of the U.S. Department of Energy is to have a zero energy commercial building by the year 2025. Windows have a major influence on the energy performance of the building envelope as they control over 55% of building energy load, and represent one important area where technologies can be developed to save energy. Aluminum framing systems are used in over 80% of commercial fenestration products (i.e. windows, curtain walls, store fronts, etc.). Aluminum framing systems are often required in commercial buildings because of their inherent good structural properties and long service life, which is required from commercial and architectural frames. At the same time, they are lightweight and durable, requiring very little maintenance, and offer design flexibility. An additional benefit of aluminum framing systems is their relatively low cost and easy manufacturability. Aluminum, being an easily recyclable material, also offers sustainable features. However, from energy efficiency point of view, aluminum frames have lower thermal performance due to the very high thermal conductivity of aluminum. Fenestration systems constructed of aluminum alloys therefore have lower performance in terms of being effective barrier to energy transfer (heat loss or gain). Despite the lower energy performance, aluminum is the choice material for commercial framing systems and dominates the commercial/architectural fenestration market because of the reasons mentioned above. In addition, there is no other cost effective and energy efficient replacement material available to take place of aluminum in the commercial/architectural market. Hence it is imperative to improve the performance of aluminum framing system to improve the energy performance of commercial fenestration system and in turn reduce the energy consumption of commercial building and achieve zero energy building by 2025. The objective of this project was to develop high performance, energy efficient commercial
MCP gated x-ray framing camera
Cai, Houzhi; Liu, Jinyuan; Niu, Lihong; Liao, Hua; Zhou, Junlan
2009-11-01
A four-frame gated microchannel plate (MCP) camera is described in this article. Each frame photocathode coated with gold on the MCP is part of a transmission line with open circuit end driven by the gating electrical pulse. The gating pulse is 230 ps in width and 2.5 kV in amplitude. The camera is tested by illuminating its photocathode with ultraviolet laser pulses, 266 nm in wavelength, which shows exposure time as short as 80 ps.
Frame Narratives and The Gothic Subject
Southward, D.
2015-01-01
So endemic to the early Gothic, yet so often critically neglected, the trope of the found manuscript, and by extension the frame narrative, is nonetheless revealing of a particular anxiety within the genre as a whole, and one which contemporary Gothic texts increasingly problematize as a force of narrative antagonism. This paper explores the relationship between the framer and framed in both Mary Shelley's classic Gothic text Frankenstein and Richard Flanagan's Tazmanian Gothic text Gould's B...
Stability of wavelet frames with matrix dilations
DEFF Research Database (Denmark)
Christensen, Ole; Sun, Wenchang
2006-01-01
Under certain assumptions we show that a wavelet frame {Tau(A(j), b(j,k))psi} (j,k is an element of Z) := {vertical bar detA(j)vertical bar(-1/2) psi(A(j)(-1)(x - b(j,k)))} (j,k is an element of Z) in L-2(R-d) remains a frame when the dilation matrices A(j) and the translation parameters b...
Quantum communication, reference frames, and gauge theory
International Nuclear Information System (INIS)
Enk, S. J. van
2006-01-01
We consider quantum communication in the case that the communicating parties not only do not share a reference frame but use imperfect quantum communication channels, in that each channel applies some fixed but unknown unitary rotation to each qubit. We discuss similarities and differences between reference frames within that quantum communication model and gauge fields in gauge theory. We generalize the concept of refbits and analyze various quantum communication protocols within the communication model
PLASTIC ANALYSIS OF STEEL FRAME STRUCTURE
Directory of Open Access Journals (Sweden)
M. Rogac
2013-05-01
Full Text Available This paper presents the plastic analysis of steel frame structure loaded by gravity loads. By applying the cinematic theorem of ultimate analysis, the ultimate load for the case of elastic - ideally plastic material is calculated. The identical structure was treated in the computer program SAP2000 where the zone of material reinforcement in the plastic area was covered. Keywords: Steel frame structure, plastic analysis, ultimate gravity load, material reinforcement.
Nonlinear stability analysis of the frame structures
Directory of Open Access Journals (Sweden)
Ćorić Stanko
2016-01-01
Full Text Available In this paper the phenomenon of instability of frames in elasto-plastic domain was investigated. Numerical analysis was performed by the finite element method. Stiffness matrices were derived using the trigonometric shape functions related to exact solution of the differential equation of bending according to the second order theory. When the buckling of structure occurs in plastic domain, it is necessary to replace the constant modulus of elasticity E with the tangent modulus Et. Tangent modulus is stress dependent function and takes into account the changes of the member stiffness in the inelastic range. For the purposes of numerical investigation in this analysis, part of the computer program ALIN was created in a way that this program now can be used for elastic and elasto-plastic stability analysis of frame structures. This program is developed in the C++ programming language. Using this program, it is possible to calculate the critical load of frames in the elastic and inelastic domain. In this analysis, the algorithm for the calculation of buckling lengths of compressed columns of the frames was also established. The algorithm is based on the calculation of the global stability analysis of frame structures. Results obtained using this algorithm were compared with the approximate solutions from the European (EC3 and national (JUS standards for the steel structures. By the given procedure in this paper it is possible to follow the behavior of the plane frames in plastic domain and to calculate the real critical load in that domain.
Framing Integration – from Welfare to Citizenship
Directory of Open Access Journals (Sweden)
Ragnhild Ihle
2014-03-01
Full Text Available This article will study the contested concept of integration in Norway through a frame analysis approach. The aim is to study different understandings of the term "integration" as it is presented in a select body of policy documents in Norway. The methodology involved is to search in the documents and in relevant research for various interpretations of the concept, and relate them to diagnostic framing, prognostic framing and motivational framing. This method is associated with both critical frame analysis and genealogy. The analysis defines a timeline, from 1975 forward, of six concepts of integration: 1 individuals in need, care and clientification; 2 preservation of culture - a tribute to colourful community; 3 the upheaval of living conditions in specific social groups; 4 absence of structural barriers, racism and discrimination; 5 living conditions, identity and belonging; 6 Influence, participation and activation. The frames related to these concepts will expose conceptual prejudices, detect inconsistencies, challenge generalisations, and give visibility to the processes of exclusion.
To end life or not to prolong life: the effect of message framing on attitudes toward euthanasia.
Gamliel, Eyal
2013-05-01
People ascribe "euthanasia" different values and view it differently. This study hypothesized that a different framing of objectively the same euthanasia situations would affect people's attitudes toward it. Indeed, "positive" framing of euthanasia as not prolonging life resulted in more support for both passive and active euthanasia relative to "negative" framing of the objectively same situations as ending life. Two experiments replicated this pattern using either continuous measures of attitude or dichotomous measures of choice. The article offers two theoretical explanations for the effect of message framing on attitudes toward euthanasia, discusses implications of this effect, and suggests future research.
Leuridan, Steven; Goossens, Quentin; Roosen, Jorg; Pastrav, Leonard; Denis, Kathleen; Mulier, Michiel; Desmet, Wim; Vander Sloten, Jos
2017-02-01
Accurate pre-clinical evaluation of the initial stability of new cementless hip stems using in vitro micromotion measurements is an important step in the design process to assess the new stem's potential. Several measuring systems, linear variable displacement transducer-based and other, require assuming bone or implant to be rigid to obtain micromotion values or to calculate derived quantities such as relative implant tilting. An alternative linear variable displacement transducer-based measuring system not requiring a rigid body assumption was developed in this study. The system combined advantages of local unidirectional and frame-and-bracket micromotion measuring concepts. The influence and possible errors that would be made by adopting a rigid body assumption were quantified. Furthermore, as the system allowed emulating local unidirectional and frame-and-bracket systems, the influence of adopting rigid body assumptions were also analyzed for both concepts. Synthetic and embalmed bone models were tested in combination with primary and revision implants. Single-legged stance phase loading was applied to the implant - bone constructs. Adopting a rigid body assumption resulted in an overestimation of mediolateral micromotion of up to 49.7μm at more distal measuring locations. Maximal average relative rotational motion was overestimated by 0.12° around the anteroposterior axis. Frontal and sagittal tilting calculations based on a unidirectional measuring concept underestimated the true tilting by an order of magnitude. Non-rigid behavior is a factor that should not be dismissed in micromotion stability evaluations of primary and revision femoral implants. Copyright © 2017 Elsevier Ltd. All rights reserved.
A stress function for 3D frame analysis
McRobie, Frank Allan; Williams, CJK
2017-01-01
This paper generalises Rankine diagrams for 3D trusses to be applicable to 3D frames. Rankine diagrams are a graphical representation of a state of self-stress in a 3D truss, with the area of reciprocal polygons representing the axial force in their corresponding original bars. Rankine diagrams are a polyhedral version of the continuous Maxwell-Rankine stress function. In this paper we present a new stress function. It is piecewise linear and discontinuous and it allows the analysis of 3D fra...
Out-of-plane (SH) soil-structure interaction: a shear wall with rigid and flexible ring foundation
Le, Thang; Lee, Vincent W.; Luo, Hao
2016-02-01
Soil-structure interaction (SSI) of a building and shear wall above a foundation in an elastic half-space has long been an important research subject for earthquake engineers and strong-motion seismologists. Numerous papers have been published since the early 1970s; however, very few of these papers have analytic closed-form solutions available. The soil-structure interaction problem is one of the most classic problems connecting the two disciplines of earthquake engineering and civil engineering. The interaction effect represents the mechanism of energy transfer and dissipation among the elements of the dynamic system, namely the soil subgrade, foundation, and superstructure. This interaction effect is important across many structure, foundation, and subgrade types but is most pronounced when a rigid superstructure is founded on a relatively soft lower foundation and subgrade. This effect may only be ignored when the subgrade is much harder than a flexible superstructure: for instance a flexible moment frame superstructure founded on a thin compacted soil layer on top of very stiff bedrock below. This paper will study the interaction effect of the subgrade and the superstructure. The analytical solution of the interaction of a shear wall, flexible-rigid foundation, and an elastic half-space is derived for incident SH waves with various angles of incidence. It found that the flexible ring (soft layer) cannot be used as an isolation mechanism to decouple a superstructure from its substructure resting on a shaking half-space.
Some properties of dual and approximate dual of fusion frames
Arefijamaal, Ali Akbar; Neyshaburi, Fahimeh Arabyani
2016-01-01
In this paper we extend the notion of approximate dual to fusion frames and present some approaches to obtain dual and approximate alternate dual fusion frames. Also, we study the stability of dual and approximate alternate dual fusion frames.
Directory of Open Access Journals (Sweden)
Bram Geron
2013-09-01
Full Text Available Programs with control are usually modeled using lambda calculus extended with control operators. Instead of modifying lambda calculus, we consider a different model of computation. We introduce continuation calculus, or CC, a deterministic model of computation that is evaluated using only head reduction, and argue that it is suitable for modeling programs with control. It is demonstrated how to define programs, specify them, and prove them correct. This is shown in detail by presenting in CC a list multiplication program that prematurely returns when it encounters a zero. The correctness proof includes termination of the program. In continuation calculus we can model both call-by-name and call-by-value. In addition, call-by-name functions can be applied to call-by-value results, and conversely.
Min, Zhe; Ren, Hongliang; Meng, Max Q-H
2017-10-01
Accurate understanding of surgical tool-tip tracking error is important for decision making in image-guided surgery. In this Letter, the authors present a novel method to estimate/model surgical tool-tip tracking error in which they take pivot calibration uncertainty into consideration. First, a new type of error that is referred to as total target registration error (TTRE) is formally defined in a single-rigid registration. Target localisation error (TLE) in two spaces to be registered is considered in proposed TTRE formulation. With first-order approximation in fiducial localisation error (FLE) or TLE magnitude, TTRE statistics (mean, covariance matrix and root-mean-square (RMS)) are then derived. Second, surgical tool-tip tracking error in optical tracking system (OTS) frame is formulated using TTRE when pivot calibration uncertainty is considered. Finally, TTRE statistics of tool-tip in OTS frame are then propagated relative to a coordinate reference frame (CRF) rigid-body. Monte Carlo simulations are conducted to validate the proposed error model. The percentage passing statistical tests that there is no difference between simulated and theoretical mean and covariance matrix of tool-tip tracking error in CRF space is more than 90% in all test cases. The RMS percentage difference between simulated and theoretical tool-tip tracking error in CRF space is within 5% in all test cases.
Sub-Frame Crossing for Streaming Video over Wireless Networks
Aziz, Hussein Muzahim; Grahn, Håkan; Lundberg, Lars
2010-01-01
Transmitting a real time video streaming over a wireless network cannot guarantee that all the frames could be received by the mobile devices. The characteristics of a wireless network in terms of the available bandwidth, frame delay, and frame losses cannot be known in advanced. In this work, we propose a new mechanism for streaming video over a wireless channel. The proposed mechanism prevents freezing frames in the mobile devices. This is done by splitting the video frame in two sub-frames...
A short introduction to frames, Gabor systems, and wavelet systems
DEFF Research Database (Denmark)
Christensen, Ole
2014-01-01
In this article we present a short survey of frame theory in Hilbert spaces. We discuss Gabor frames and wavelet frames, and a recent transform that allows to move results from one setting into the other and vice versa.......In this article we present a short survey of frame theory in Hilbert spaces. We discuss Gabor frames and wavelet frames, and a recent transform that allows to move results from one setting into the other and vice versa....
International Nuclear Information System (INIS)
Broadbent, H A; Ketterl, T P; Reid, C S
2010-01-01
The design, fabrication and initial performance of a single substrate, miniature, low-cost conductivity, temperature, depth (CTD) sensor board with interconnects are presented. In combination these sensors measure ocean salinity. The miniature CTD device board was designed and fabricated as the main component of a 50 mm × 25 mm × 25 mm animal-attached biologger. The board was fabricated using printed circuit processes and consists of two distinct regions on a continuous single liquid crystal polymer substrate: an 18 mm × 28 mm rigid multi-metal sensor section and a 72 mm long flexible interconnect section. The 95% confidence intervals for the conductivity, temperature and pressure sensors were demonstrated to be ±0.083 mS cm −1 , 0.01 °C, and ±0.135 dbar, respectively.
Classification of rigid and deformable objects using a novel tactile sensor
DEFF Research Database (Denmark)
Drimus, Alin; Kootstra, Gert; Bilberg, Arne
2011-01-01
In this paper, we present a novel array tactile sensor for use in robotic grippers based on a flexible piezoresistive rubber. We start by describing the physical principles of piezoresistive materials and continue by outlining how to build a flexible array tactile sensor using stitch electrodes...... various rigid and deformable objects. We represent the array of tactile images for each grasped object to a time series of features and use this as the input for a KNN classifier. Dynamic time warping is used for calculating distances between different time series of features. In the end, we compare...... the results with the ones obtained from an experimental setup that uses a Weiss Robotics tactile sensor with similar characteristics and we conclude by exemplifying how the results of the classification can be used in different industrial applications....
Rigid Patient Positioning is Unreliable in Total Hip Arthroplasty.
Milone, Michael T; Schwarzkopf, Ran; Meere, Patrick A; Carroll, Kaitlin M; Jerabek, Seth A; Vigdorchik, Jonathan
2017-06-01
To our knowledge, no study has assessed the ability of rigid patient positioning devices to afford arthroplasty surgeons with ideal acetabular orientation throughout surgery. The purpose of this study is to use robotic arm-assisted computer navigation to assess the reliability of pelvic position in total hip arthroplasty performed on patients positioned with rigid positioning devices. A prospective cohort of 100 hips (94 patients) underwent robotic-guided total hip arthroplasty in the lateral decubitus position from the posterior approach, 77 stabilized by universal lateral positioner, and 23 by peg board. Before reaming, computed tomography-templated computer software generated true values of pelvic anteversion and inclination based on the position of the robot arm registered to the patient's preoperative pelvic computed tomography. Mean alteration in anteversion and inclination values was 1.7° (absolute value, 5.3°; range, -20° to 20°) and 1.6° (absolute value, 2.6°; range, -8° to 10°), respectively. And 22% of anteversion values were altered by >10° and 41% by >5°. There was no difference between hip positioners used (P = .36). Anteversion variability was correlated with body mass index (P = .02). Despite the use of rigid patient positioning devices-a lateral hip positioner or peg board-this study reveals clinically important malposition of the pelvis in many cases, especially with regard to anteversion. These results show a clear need to pay particular attention to anatomic landmarks or computer-assisted techniques to assure accurate acetabular cup positioning. Patient positioning should not be solely trusted. Copyright © 2017 Elsevier Inc. All rights reserved.
Vertical dimensional stability and rigidity of occlusal registration materials.
Walker, Mary P; Wu, Edis; Heckman, M Elizabeth; Alderman, Nicholas
2009-01-01
Dimensionally accurate occlusal registration records are essential for restorative dentistry; moreover, since records are not used immediately or may be used more than once, the registration material should exhibit accuracy over time (a concept known as dimensional stability). It has been speculated that materials with increased hardness or rigidity should produce more accurate registration records due to an increased resistance to distortion. This study compared the rigidity and associated dimensional accuracy of a recently marketed bisacrylic occlusal registration material and a vinyl polysiloxane (VPS). Maxillary and mandibular typodont arches were mounted on a plasterless articulator from which teeth No. 3, 13, and 15 had been removed to simulate edentulous spaces. After preparing teeth No. 2, 4, 12, and 14 as bridge abutments, the remaining teeth were equilibrated selectively to produce even anterior contact. Four digital photographs were taken to make vertical interarch measurements at four locations (teeth No. 3, 7, 10, and 14). Following initial photos (controls), 10 interocclusal records were made using each registration material, with material placed only in the segments in which teeth were prepared. The records were used for mounting the maxillary arch against the mandibular arch after 48, 72, and 120 hours. There were significant effects on vertical dimensional change related to arch location, material, and mounting time. Both materials demonstrated significantly larger posterior vertical openings than anterior vertical openings, while the bisacrylate produced a larger posterior opening than VPS at 48 and 72 hours and a larger anterior opening at all mounting times. There also was a significant difference in hardness/rigidity due to material and measurement time; at all measurement times, bisacrylate exhibited a significantly higher hardness number.
A genetic scale of reading frame coding.
Michel, Christian J
2014-08-21
The reading frame coding (RFC) of codes (sets) of trinucleotides is a genetic concept which has been largely ignored during the last 50 years. A first objective is the definition of a new and simple statistical parameter PrRFC for analysing the probability (efficiency) of reading frame coding (RFC) of any trinucleotide code. A second objective is to reveal different classes and subclasses of trinucleotide codes involved in reading frame coding: the circular codes of 20 trinucleotides and the bijective genetic codes of 20 trinucleotides coding the 20 amino acids. This approach allows us to propose a genetic scale of reading frame coding which ranges from 1/3 with the random codes (RFC probability identical in the three frames) to 1 with the comma-free circular codes (RFC probability maximal in the reading frame and null in the two shifted frames). This genetic scale shows, in particular, the reading frame coding probabilities of the 12,964,440 circular codes (PrRFC=83.2% in average), the 216 C(3) self-complementary circular codes (PrRFC=84.1% in average) including the code X identified in eukaryotic and prokaryotic genes (PrRFC=81.3%) and the 339,738,624 bijective genetic codes (PrRFC=61.5% in average) including the 52 codes without permuted trinucleotides (PrRFC=66.0% in average). Otherwise, the reading frame coding probabilities of each trinucleotide code coding an amino acid with the universal genetic code are also determined. The four amino acids Gly, Lys, Phe and Pro are coded by codes (not circular) with RFC probabilities equal to 2/3, 1/2, 1/2 and 2/3, respectively. The amino acid Leu is coded by a circular code (not comma-free) with a RFC probability equal to 18/19. The 15 other amino acids are coded by comma-free circular codes, i.e. with RFC probabilities equal to 1. The identification of coding properties in some classes of trinucleotide codes studied here may bring new insights in the origin and evolution of the genetic code. Copyright © 2014 Elsevier
Rigid-Plastic Post-Buckling Analysis of Columns and Quadratic Plates
DEFF Research Database (Denmark)
Jönsson, Jeppe
2008-01-01
The objective of this paper is to show the application of a novel approach to the rigid plastic hinge and yield line theory in post-buckling analysis of slender plates and columns. The upper bound theorem of plasticity theory and the associated flow law of plasticity are used to find...... yield lines accommodate differential rotations of rigid parts and the area “collapse” yield lines accommodate local area changes of the rigid parts thereby preserving compatibility of the rigid parts of a plate. The approach will be illustrated for rigid plastic column analysis and for a quadratic plate...... of the post-buckling behaviour. The rigid plastic theory of plates, referred to as yield line theory, involves large rigid parts of the plate mutually rotating about yielding hinge lines, however in order to accommodate in plane plastic deformations area “collapse” yield lines have been introduced. The hinge...
Rigid body formulation in a finite element context with contact interaction
Refachinho de Campos, Paulo R.; Gay Neto, Alfredo
2018-03-01
The present work proposes a formulation to employ rigid bodies together with flexible bodies in the context of a nonlinear finite element solver, with contact interactions. Inertial contributions due to distribution of mass of a rigid body are fully developed, considering a general pole position associated with a single node, representing a rigid body element. Additionally, a mechanical constraint is proposed to connect a rigid region composed by several nodes, which is useful for linking rigid/flexible bodies in a finite element environment. Rodrigues rotation parameters are used to describe finite rotations, by an updated Lagrangian description. In addition, the contact formulation entitled master-surface to master-surface is employed in conjunction with the rigid body element and flexible bodies, aiming to consider their interaction in a rigid-flexible multibody environment. New surface parameterizations are presented to establish contact pairs, permitting pointwise interaction in a frictional scenario. Numerical examples are provided to show robustness and applicability of the methods.
Sim, Jaehyun; Sim, Jun; Park, Eunsung; Lee, Julian
2015-06-01
Many proteins undergo large-scale motions where relatively rigid domains move against each other. The identification of rigid domains, as well as the hinge residues important for their relative movements, is important for various applications including flexible docking simulations. In this work, we develop a method for protein rigid domain identification based on an exhaustive enumeration of maximal rigid domains, the rigid domains not fully contained within other domains. The computation is performed by mapping the problem to that of finding maximal cliques in a graph. A minimal set of rigid domains are then selected, which cover most of the protein with minimal overlap. In contrast to the results of existing methods that partition a protein into non-overlapping domains using approximate algorithms, the rigid domains obtained from exact enumeration naturally contain overlapping regions, which correspond to the hinges of the inter-domain bending motion. The performance of the algorithm is demonstrated on several proteins. © 2015 Wiley Periodicals, Inc.
Wood frame systems for wood homes
Directory of Open Access Journals (Sweden)
Julio Cesar Molina
2010-12-01
Full Text Available The use of constructive systems that combine strength, speed, with competitive differential techniques and mainly, compromising with the environment, is becoming more popular in Brazil. The constructive system in wood frame for houses of up to five stories is very interesting, because it is a light system, structured in reforested treated wood which allows the combination of several materials, besides allowing speed in the construction and total control of the expenses already in the project phase for being industrialized. The structural behavior of the wood frame is superior to the structural masonry in strength, thermal and acoustic comfort. However, in Brazil, the wood frame is still little known and used, due to lack of technical knowledge about the system, prejudice associated the bad use of the wood as construction material, or still, in some cases, lack of normalization. The aim of this manuscript consists of presenting the main technical characteristics and advantages of the constructive system in wood frame homes, approaching the main stages of the constructive process through examples, showing the materials used in the construction, in addition the main international normative recommendations of the project. Thus, this manuscript also hopes to contribute to the popularization of the wood frame system in Brazil, since it is a competitive, fast and ecologically correct system. Moreover, nowadays, an enormous effort of the technical, commercial and industrial section has been accomplished for the development of this system in the country.
Physics of Non-Inertial Reference Frames
International Nuclear Information System (INIS)
Kamalov, Timur F.
2010-01-01
Physics of non-inertial reference frames is a generalizing of Newton's laws to any reference frames. It is the system of general axioms for classical and quantum mechanics. The first, Kinematics Principle reads: the kinematic state of a body free of forces conserves and equal in absolute value to an invariant of the observer's reference frame. The second, Dynamics Principle extended Newton's second law to non-inertial reference frames and also contains additional variables there are higher derivatives of coordinates. Dynamics Principle reads: a force induces a change in the kinematic state of the body and is proportional to the rate of its change. It is mean that if the kinematic invariant of the reference frame is n-th derivative with respect the time, then the dynamics of a body being affected by the force F is described by the 2n-th differential equation. The third, Statics Principle reads: the sum of all forces acting a body at rest is equal to zero.
Manufacturing of neutron reflector frame for JMTR
International Nuclear Information System (INIS)
Hanawa, Yoshio; Tsuboi, Kazuaki; Takahashi, Kunihiro; Uchida, Munenori; Suzuki, Ken
2010-03-01
Beryllium has been used as the neutron reflector in the Japan Materials Testing Reactor (JMTR). A beryllium frame is arranged in the JMTR core and the frame consists of 3 sections (North, East and West). Each section has 7 stories of the beryllium blocks. Each block is connected by the aluminium joints. The capsule or the berylium plug is located in the inside of the beryllium frame. The first criticality achieved in 1968 and the frame has been replaced 6 times and now the 7th frame is being manufactured. The replacement is planned to be done in the spring of 2010. The design has been modified to decrease the swelling camber and the lifetime has been improved. The manufacturing procedure is severely controlled to assure the quality. The chemical composition must be specified to minimize the swelling and radiation. The machining procedure is highly controlled because beryllium is very brittle. And the environmental control is also important, because the beryllium is a toxic material. (author)
Symmetry and Reduction for Coordinated Rigid Body Networks
Hanszligmann, H; Smith, T R
2004-01-01
Motivated by interest in the collective behavior of autonomous agents, we study networks of rigid bodies and the problem of coordinated orientation and position across the group. Our main result is the reduction of the networked system in the case that individuals are coupled by control inputs that depend only on relative configuration. We use reduction theory based on semi-direct products; this yields flat Poisson spaces which enable efficient formulation of control laws. In the second part of the paper, we apply the reduction results to particular choices of kinetic energy and prove stability of coordinated behaviors.
Microstructural Dynamics and Rheology of Suspensions of Rigid Fibers
Butler, Jason E.; Snook, Braden
2018-01-01
The dynamics and rheology of suspensions of rigid, non-Brownian fibers in Newtonian fluids are reviewed. Experiments, theories, and computer simulations are considered, with an emphasis on suspensions at semidilute and concentrated conditions. In these suspensions, interactions between the particles strongly influence the microstructure and rheological properties of the suspension. The interactions can arise from hydrodynamic disturbances, giving multibody interactions at long ranges and pairwise lubrication forces over short distances. For concentrated suspensions, additional interactions due to excluded volume (contacts) and adhesive forces are addressed. The relative importance of the various interactions as a function of fiber concentration is assessed.
On the surprising rigidity of the Pauli exclusion principle
International Nuclear Information System (INIS)
Greenberg, O.W.
1989-01-01
I review recent attempts to construct a local quantum field theory of small violations of the Pauli exclusion principle and suggest a qualitative reason for the surprising rigidity of the Pauli principle. I suggest that small violations can occur in our four-dimensional world as a consequence of the compactification of a higher-dimensional theory in which the exclusion principle is exactly valid. I briefly mention a recent experiment which places a severe limit on possible violations of the exclusion principle. (orig.)
Centrifuge modelling of rigid piles in soft clay
DEFF Research Database (Denmark)
Klinkvort, R.T.; Poder, M.; Truong, P.
2016-01-01
of this study is to employ centrifuge modelling in order to derive experimental p-y curves for rigid piles embedded in over-consolidated soft clay. A kaolin clay sample was prepared and pre-consolidated by applying a constant pressure at the soil surface, while different over-consolidation ratios were achieved...... within the clay sample by carrying out the experiments at different g fields. The findings suggest that the normalised shape of the p-y curves can be predicted within a sufficient accuracy using the current methodology but that the ultimate lat-eral resistance is underestimated at shallow depths...
Cosmic ray fluctuations at rigidities 4 to 180 GV
International Nuclear Information System (INIS)
Benko, G.; Erdoes, G.; Stehlik, M.; Katz, M.E.; Nosov, S.F.
1986-07-01
The power spectral density of cosmic ray fluctuations observed at both underground and ground level during the years 1976-1980 was calculated. The spectral index is independent of the phase of solar cycle in the frequency range of 5x10 -7 - 5x10 -5 Hz and its value is equal to 2. The level of fluctuations shows a weak dependence on the rigidity (R) of the particles P∼R -2/3 . The obtained experimental results are in agreement with the theoretical predictions. (author)
Rigidity of minimal submanifolds with flat normal bundle
Indian Academy of Sciences (India)
Rigidity of minimal submanifolds with flat normal bundle. 461. = a. ∫. M u2(1+q)+ 2 a f 2 − 2. ∫. M u2q+1f 〈∇f, ∇u〉. − (2q + 1). ∫. M u2qf 2|∇u|2, which gives a .... that depends on n, ϵ and q. We now try to transform (2.15) the right hand side only involved u in the power two. For that, we use Young's inequality: ab ≤ βsas.
Assessment of Lumped-Parameter Models for Rigid Footings
DEFF Research Database (Denmark)
Andersen, Lars
2010-01-01
The quality of consistent lumped-parameter models of rigid footings is examined. Emphasis is put on the maximum response during excitation and the geometrical damping related to free vibrations. The optimal order of a lumped-parameter model is determined for each degree of freedom, i.e. horizontal...... and vertical translations as well as torsion and rocking, and the necessity of coupling between horizontal sliding and rocking is discussed. Most of the analyses are carried out for hexagonal footings; but in order to generalise the conclusions to a broader variety of footings, comparisons are made...... with the response of circular and square foundations....
Nonlinear complex dynamics and Keynesian rigidity: A short introduction
Jovero, Edgardo
2005-09-01
The topic of this paper is to show that the greater acceptance and intense use of complex nonlinear dynamics in macroeconomics makes sense only within the neoKeynesian tradition. An example is presented regarding the behavior of an open-economy two-sector growth model endowed with Keynesian rigidity. The Keynesian view that structural instability globally exists in the aggregate economy is put forward, and therefore the need arises for policy to alleviate this instability in the form of dampened fluctuations is presented as an alternative view for macroeconomic theorizing.
Rigid supersymmetry from conformal supergravity in five dimensions
Pini, Alessandro; Rodriguez-Gomez, Diego; Schmude, Johannes
2015-09-01
We study the rigid limit of 5d conformal supergravity with minimal supersymmetry on Riemannian manifolds. The necessary and sufficient condition for the existence of a solution is the existence of a conformal Killing vector. Whenever a certain SU(2) curvature becomes abelian the backgrounds define a transversally holomorphic foliation. Subsequently we turn to the question under which circumstances these backgrounds admit a kinetic Yang-Mills term in the action of a vector multiplet. Here we find that the conformal Killing vector has to be Killing. We supplement the discussion with various appendices.
Rigid supersymmetry from conformal supergravity in five dimensions
Energy Technology Data Exchange (ETDEWEB)
Pini, Alessandro [Department of Physics, Universidad de Oviedo, Avda. Calvo Sotelo 18, 33007, Oviedo (Spain); Centre for Research in String Theory, School of Physics, Queen Mary University of London,Mile End Road, London, E1 4NS (United Kingdom); Rodriguez-Gomez, Diego; Schmude, Johannes [Department of Physics, Universidad de Oviedo, Avda. Calvo Sotelo 18, 33007, Oviedo (Spain)
2015-09-17
We study the rigid limit of 5d conformal supergravity with minimal supersymmetry on Riemannian manifolds. The necessary and sufficient condition for the existence of a solution is the existence of a conformal Killing vector. Whenever a certain SU(2) curvature becomes abelian the backgrounds define a transversally holomorphic foliation. Subsequently we turn to the question under which circumstances these backgrounds admit a kinetic Yang-Mills term in the action of a vector multiplet. Here we find that the conformal Killing vector has to be Killing. We supplement the discussion with various appendices.
Spinor and twistor formulations of massless particles with rigidity
Energy Technology Data Exchange (ETDEWEB)
Deguchi, Shinichi, E-mail: deguchi@phys.cst.nihon-u.ac.jp [Institute of Quantum Science, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo 101-8308 (Japan); Suzuki, Takafumi [Junior College Funabashi Campus, Nihon University, Narashinodai, Funabashi, Chiba 274-8501 (Japan)
2014-04-04
The 4-dimensional model of a massless particle with rigidity whose Lagrangian is proportional to its world-line curvature is reformulated in terms of spinor and twistor variables. We begin with a first-order Lagrangian that is equivalent to the original Lagrangian proportional to the extrinsic curvature of a particle world-line. The first-order Lagrangian is written in terms of spacetime and spinor variables, leading to a spinor representation of the Lagrangian. Then its corresponding action is expressed in terms of twistor variables, leading to the gauged Shirafuji action.
The impact of cine EPID image acquisition frame rate on markerless soft-tissue tracking
International Nuclear Information System (INIS)
Yip, Stephen; Rottmann, Joerg; Berbeco, Ross
2014-01-01
Purpose: Although reduction of the cine electronic portal imaging device (EPID) acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor autotracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87 Hz with an amorphous silicon portal imager (AS1000, Varian Medical Systems, Palo Alto, CA). The maximum frame rate of 12.87 Hz is imposed by the EPID. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for autotracking. The difference between the programmed and autotracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at 11 field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise are correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the autotracking errors increased at frame rates lower than 4.29 Hz. Above 4.29 Hz, changes in errors were negligible withδ < 1.60 mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R = 0.94) and patient studies (R = 0.72). Moderate to poor correlation was found between image noise and tracking error with R −0.58 and −0.19 for both studies, respectively. Conclusions: Cine EPID
On Λ-Type Duality of Frames in Banach Spaces
Directory of Open Access Journals (Sweden)
Renu Chugh
2013-11-01
Full Text Available Frames are redundant system which are useful in the reconstruction of certain classes of spaces. The dual of a frame (Hilbert always exists and can be obtained in a natural way. Due to the presence of three Banach spaces in the definition of retro Banach frames (or Banach frames duality of frames in Banach spaces is not similar to frames for Hilbert spaces. In this paper we introduce the notion of Λ-type duality of retro Banach frames. This can be generalized to Banach frames in Banach spaces. Necessary and sufficient conditions for the existence of the dual of retro Banach frames are obtained. A special class of retro Banach frames which always admit a dual frame is discussed.
Construction sector development: frames and governance responses
DEFF Research Database (Denmark)
Jensen, Jens Stissing; Gottlieb, Stefan C.; Thuesen, Christian Langhoff
2011-01-01
The governance of construction sector development constitutes an important policy issue in many European countries due to the increasing impact that construction as well as the built environment have on gross domestic product and the environment. Previous studies have discussed how national...... construction industries have been framed as objects of development. However, less attention has been placed on exploring how an industry is recognized and framed as an object that can be subjected to organized development activities from the viewpoint of strategically motivated actors, and how such framing...... activities may be governed. Based on a case study of the sector development activities in the Danish construction industry, this paper argues that governance strategies should not necessarily be designed to ensure the development of a single industrial conceptualization. First, drawing on concepts from...
Hamiltonian deformations of Gabor frames: First steps.
de Gosson, Maurice A
2015-03-01
Gabor frames can advantageously be redefined using the Heisenberg-Weyl operators familiar from harmonic analysis and quantum mechanics. Not only does this redefinition allow us to recover in a very simple way known results of symplectic covariance, but it immediately leads to the consideration of a general deformation scheme by Hamiltonian isotopies ( i.e. arbitrary paths of non-linear symplectic mappings passing through the identity). We will study in some detail an associated weak notion of Hamiltonian deformation of Gabor frames, using ideas from semiclassical physics involving coherent states and Gaussian approximations. We will thereafter discuss possible applications and extensions of our method, which can be viewed - as the title suggests - as the very first steps towards a general deformation theory for Gabor frames.
Scaffolding Advanced Writing through Writing Frames
Directory of Open Access Journals (Sweden)
Sara Salehpour
2014-05-01
Full Text Available Mastering writing has always proved an almost insurmountable barrier to EFL learners. In an attempt to alleviate problems advanced EFL learners have with writing, this study aimed at investigating the effect of scaffolded instruction through writing frames constructed from extended prefabricated lexical bundles. 40 female advanced English students, selected out of a population of 65, were randomly assigned into experimental and control groups. The participants of both groups were assigned a writing pre-test prior to any instruction, and a writing post-test following the twenty-session scaffolded instruction in both groups. The results revealed that the participants in the experimental group outperformed their counterparts in the control group as a result of the writing frames they were provided with. Overall, it is concluded that scaffolded instruction through writing frames can be a useful means of helping advanced students to improve their writing quality.
Frame Complexity and the Financial Crisis
DEFF Research Database (Denmark)
Kleinnijenhuis, Jan; Schultz, Friederike; Oegema, Dirk
2015-01-01
Communicative complexity concerns the variety of issues and stakeholders (agenda complexity) and their associations (frame complexity) in the news. One issue may dominate news in crises (9/11, Katrina), but as soon as complexity recovers, uncertainty may decrease and the public mood may improve....... The financial crisis in the United States, the United Kingdom, and Germany (2007–2012) offers an example. An automated content analysis was applied to over 160,000 newspaper articles. Frame complexity decreased until the spotlight fell on the demise of Bear Stearns and Lehman Brothers (2008). The subsequent...... gradual recovery was only partly interrupted by the euro crisis. A Vector AutoRegression time series analysis shows that increasing frame complexity may indeed have fostered the recovery of financial markets and consumer confidence....
Karakaşlı, Ahmet; Ceçen, Berivan; Erduran, Mehmet; Taylan, Orçun; Hapa, Onur; Havıtcıoğlu, Hasan
2014-01-01
This study aims to examine the motion and stability of the adjacent segment following rigid fixation of the lumbar spine. The study included 17 fresh-frozen lamb lumbar spines (including the sacrum to T12). Biomechanical testing was performed using an axial compression testing machine. Axial compression was applied to all the specimens using a loading speed of 5 mm min-1. A specifically designed fixture was used to generate torque ≤8400 Nmm. The fixture was used with each specimen to achieve flexion and extension, axial neutral compression, and right and left bending. All specimens were tested intact, and again after implantation using posterior pedicle screws and rod fixation. During testing intervertebral displacement at the adjacent level (L5-S1) was recorded continuously via extensometry. Axial compression and superior-inferior displacement were lower in the adjacent segment (L5-S1) than anterior-posterior displacement following rigid fixation. Statistical analysis showed that there was a numerical difference and a significant change between the intact spine and the adjacent segment in the axial compression and extension positions (p<0.027). The intact spines demonstrated the maximum displacement and the difference in extension positions were significant (p<0.015). Rigid fixation of the lumbar spine altered the range of motion at the adjacent segment level. As such, abnormal stress on the adjacent segment causes spinal instability, which may subsequently cause facet joint degeneration and low back pain.
Zhen, Shanshan; Yu, Rongjun
2016-07-20
Human risk-taking attitudes can be influenced by two logically equivalent but descriptively different frames, termed the framing effect. The classic hypothetical vignette-based task (Asian disease problem) and a recently developed reward-based gambling task have been widely used to assess individual differences in the framing effect. Previous studies treat framing bias as a stable trait that has genetic basis. However, these two paradigms differ in terms of task domain (loss vs. gain) and task context (vignette-based vs. reward-based) and the convergent validity of these measurements remains unknown. Here, we developed a vignette-based task and a gambling task in both gain and loss domains and tested correlations of the framing effect among these tasks in 159 young adults. Our results revealed no significant correlation between the vignette-based task in the loss domain and the gambling task in the gain domain, indicating low convergent validity. The current findings raise the question of how to measure the framing effect precisely, especially in individual difference studies using large samples and expensive neuroscience methods. Our results suggest that the framing effect is influenced by both task domain and task context and future research should be cautious about the operationalization of the framing effect.
News framing and public opinion: A mediation analysis of framing effects on political attitudes
Lecheler, S.K.; de Vreese, C.H.
2012-01-01
There is no satisfactory account of the psychological processes that mediate a news framing effect. Based on an experimental study (N = 1,537), this article presents a mediation analysis of a news framing effect on opinion, testing for two important mediation processes: belief importance and belief
Authentication of Surveillance Videos: Detecting Frame Duplication Based on Residual Frame.
Fadl, Sondos M; Han, Qi; Li, Qiong
2017-10-16
Nowadays, surveillance systems are used to control crimes. Therefore, the authenticity of digital video increases the accuracy of deciding to admit the digital video as legal evidence or not. Inter-frame duplication forgery is the most common type of video forgery methods. However, many existing methods have been proposed for detecting this type of forgery and these methods require high computational time and impractical. In this study, we propose an efficient inter-frame duplication detection algorithm based on standard deviation of residual frames. Standard deviation of residual frame is applied to select some frames and ignore others, which represent a static scene. Then, the entropy of discrete cosine transform coefficients is calculated for each selected residual frame to represent its discriminating feature. Duplicated frames are then detected exactly using subsequence feature analysis. The experimental results demonstrated that the proposed method is effective to identify inter-frame duplication forgery with localization and acceptable running time. © 2017 American Academy of Forensic Sciences.
NChina16: A stable geodetic reference frame for geological hazard studies in North China
Wang, Guoquan; Bao, Yan; Gan, Weijun; Geng, Jianghui; Xiao, Gengru; Shen, Jack S.
2018-04-01
We have developed a stable North China Reference Frame 2016 (NChina16) using five years of continuous GPS observations (2011.8-2016.8) from 12 continuously operating reference stations (CORS) fixed to the North China Craton. Applications of NChina16 in landslide and subsidence studies are illustrated in this article. A method for realizing a regional geodetic reference frame is introduced. The primary result of this study is the seven parameters for transforming Cartesian ECEF (Earth-Centered, Earth-Fixed) coordinates X, Y, and Z from the International GNSS Service Reference Frame 2008 (IGS08) to NChina16. The seven parameters include the epoch that is used to align the regional reference frame to IGS08 and the time derivatives of three translations and three rotations. The GIPSY-OASIS (V6.4) software package was used to obtain the precise point positioning (PPP) daily solutions with respect to IGS08. The frame stability of NChina16 is approximately 0.5 mm/year in both horizontal and vertical directions. This study also developed a regional model for correcting seasonal motions superimposed into the vertical component of the GPS-derived displacement time series. Long-term GPS observations (1999-2016) from five CORS in North China were used to develop the seasonal model. According to this study, the PPP daily solutions with respect to NChina16 could achieve 2-3 mm horizontal accuracy and 4-5 mm vertical accuracy after being modified by the regional model. NChina16 will be critical to study geodynamic problems in North China, such as earthquakes, faulting, subsidence, and landslides. The regional reference frame will be periodically updated every few years to mitigate degradation of the frame with time and be synchronized with the update of IGS reference frame.
High frame rate synthetic aperture duplex imaging
DEFF Research Database (Denmark)
Stuart, Matthias Bo; Tomov, Borislav Gueorguiev; Pihl, Michael Johannes
2013-01-01
aperture flow imaging as demonstrated in this paper. Synthetic aperture, directional beamforming, and cross-correlation are used to produce B-mode and vector velocity images at high frame rates. The frame rate equals the effective pulse repetition frequency of each imaging mode. Emissions for making the B...... is determined by estimating the flow velocity in all directions and choosing the one with the strongest correlation. The method works for all angles, including fully axial and fully transverse flows. Field II simulations with a 192 element, 7 MHz linear array are made of laminar, transverse flow profiles...
Riemannian geometry in an orthogonal frame
Cartan, Elie Joseph
2001-01-01
Foreword by S S Chern. In 1926-27, Cartan gave a series of lectures in which he introduced exterior forms at the very beginning and used extensively orthogonal frames throughout to investigate the geometry of Riemannian manifolds. In this course he solved a series of problems in Euclidean and non-Euclidean spaces, as well as a series of variational problems on geodesics. In 1960, Sergei P Finikov translated from French into Russian his notes of these Cartan's lectures and published them as a book entitled Riemannian Geometry in an Orthogonal Frame. This book has many innovations, such as the n
Expanding Technological Frames Towards Mediated Collaboration
DEFF Research Database (Denmark)
Bjørn, Pernille; Scupola, Ada; Fitzgerald, Brian
2006-01-01
This paper provides an in-depth analysis of technological and social factors leading to the successful adoption of groupware in a virtual team in educational setting. Drawing on a theoretical framework based on the concept of technological frames, we conducted an action research study to analyze...... the chronological sequence of events leading to groupware adoption. We argue that groupware adoption can be conceptualized as a three-step process of expanding and aligning individual technological frames towards groupware: The first step comprises activities facilitating participants in articulation and evaluation...... collaborative practice and use of technology, and that this activity cannot take place at the outset....
A protoscientific master metaphor for framing violence.
Krauss, Herbert H
2006-11-01
Every new field of investigation requires a guiding scheme or frame. Its purpose is to provide a heuristic for discovery and a structure for organizing information. Neither the World Health Organization's public health nor a biosocial model of violence are adequate for providing a protoscientific frame for conceptualizing violent acts. This essay suggests a master metaphor--Burke's Dramatism--through which to deepen and expand our knowledge of violence and what must be done to reduce its toll. An illustrative example is presented.
Computational Fluid Dynamics Demonstration of Rigid Bodies in Motion
Camarena, Ernesto; Vu, Bruce T.
2011-01-01
The Design Analysis Branch (NE-Ml) at the Kennedy Space Center has not had the ability to accurately couple Rigid Body Dynamics (RBD) and Computational Fluid Dynamics (CFD). OVERFLOW-D is a flow solver that has been developed by NASA to have the capability to analyze and simulate dynamic motions with up to six Degrees of Freedom (6-DOF). Two simulations were prepared over the course of the internship to demonstrate 6DOF motion of rigid bodies under aerodynamic loading. The geometries in the simulations were based on a conceptual Space Launch System (SLS). The first simulation that was prepared and computed was the motion of a Solid Rocket Booster (SRB) as it separates from its core stage. To reduce computational time during the development of the simulation, only half of the physical domain with respect to the symmetry plane was simulated. Then a full solution was prepared and computed. The second simulation was a model of the SLS as it departs from a launch pad under a 20 knot crosswind. This simulation was reduced to Two Dimensions (2D) to reduce both preparation and computation time. By allowing 2-DOF for translations and 1-DOF for rotation, the simulation predicted unrealistic rotation. The simulation was then constrained to only allow translations.
Biomimetic model systems of rigid hair beds: Part II - Experiment
Jammalamadaka, Mani S. S.; Hood, Kaitlyn; Hosoi, Anette
2017-11-01
Crustaceans - such as lobsters, crabs and stomapods - have hairy appendages that they use to recognize and track odorants in the surrounding fluid. An array of rigid hairs impedes flow at different rates depending on the spacing between hairs and the Reynolds number, Re. At larger Reynolds number (Re>1), fluid travels through the hairs rather than around them, a phenomenon called leakiness. Crustaceans flick their appendages at different speeds in order to manipulate the leakiness between the hairs, allowing the hairs to either detect the odors in a sample of fluid or collect a new sample. Theoretical and numerical studies predict that there is a fast flow region near the hairs that moves closer to the hairs as Re increases. Here, we test this theory experimentally. We 3D printed rigid hairs with an aspect ratio of 30:1 in rectangular arrays with different hair packing fractions. We custom built an experimental setup which establishes poiseuille flow at intermediate Re, Re <=200. We track the flow dynamics through the hair beds using tracer particles and Particle Imaging Velocimetry. We will then compare the modelling predictions with the experimental outcomes.
Awake craniotomy using electromagnetic navigation technology without rigid pin fixation.
Morsy, Ahmed A; Ng, Wai Hoe
2015-11-01
We report our institutional experience using an electromagnetic navigation system, without rigid head fixation, for awake craniotomy patients. The StealthStation® S7 AxiEM™ navigation system (Medtronic, Inc.) was used for this technique. Detailed preoperative clinical and neuropsychological evaluations, patient education and contrast-enhanced MRI (thickness 1.5mm) were performed for each patient. The AxiEM Mobile Emitter was typically placed in a holder, which was mounted to the operating room table, and a non-invasive patient tracker was used as the patient reference device. A monitored conscious sedation technique was used in all awake craniotomy patients, and the AxiEM Navigation Pointer was used for navigation during the procedure. This offers the same accuracy as optical navigation, but without head pin fixation or interference with intraoperative neurophysiological techniques and surgical instruments. The application of the electromagnetic neuronavigation technology without rigid head fixation during an awake craniotomy is accurate, and offers superior patient comfort. It is recommended as an effective adjunctive technique for the conduct of awake surgery. Copyright © 2015 Elsevier Ltd. All rights reserved.
Heat Transfer Modeling for Rigid High-Temperature Fibrous Insulation
Daryabeigi, Kamran; Cunnington, George R.; Knutson, Jeffrey R.
2012-01-01
Combined radiation and conduction heat transfer through a high-temperature, high-porosity, rigid multiple-fiber fibrous insulation was modeled using a thermal model previously used to model heat transfer in flexible single-fiber fibrous insulation. The rigid insulation studied was alumina enhanced thermal barrier (AETB) at densities between 130 and 260 kilograms per cubic meter. The model consists of using the diffusion approximation for radiation heat transfer, a semi-empirical solid conduction model, and a standard gas conduction model. The relevant parameters needed for the heat transfer model were estimated from steady-state thermal measurements in nitrogen gas at various temperatures and environmental pressures. The heat transfer modeling methodology was evaluated by comparison with standard thermal conductivity measurements, and steady-state thermal measurements in helium and carbon dioxide gases. The heat transfer model is applicable over the temperature range of 300 to 1360 K, pressure range of 0.133 to 101.3 x 10(exp 3) Pa, and over the insulation density range of 130 to 260 kilograms per cubic meter in various gaseous environments.
Collisions of Constrained Rigid Body Systems with Friction
Directory of Open Access Journals (Sweden)
Haijun Shen
1998-01-01
Full Text Available A new approach is developed for the general collision problem of two rigid body systems with constraints (e.g., articulated systems, such as massy linkages in which the relative tangential velocity at the point of contact and the associated friction force can change direction during the collision. This is beyond the framework of conventional methods, which can give significant and very obvious errors for this problem, and both extends and consolidates recent work. A new parameterization and theory characterize if, when and how the relative tangential velocity changes direction during contact. Elastic and dissipative phenomena and different values for static and kinetic friction coefficients are included. The method is based on the explicitly physical analysis of events at the point of contact. Using this method, Example 1 resolves (and corrects a paradox (in the literature of the collision of a double pendulum with the ground. The method fundamentally subsumes other recent models and the collision of rigid bodies; it yields the same results as conventional methods when they would apply (Example 2. The new method reformulates and extends recent approaches in a completely physical context.
Modyfication of the Rigid Polyurethane-Polyisocyanurate Foams
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Bogusław Czupryński
2014-01-01
Full Text Available The effect of polyethylene glycol 1500 on physicomechanical properties of rigid polyurethane-polyisocyanurate (PUR-PIR foams has been studied. It was found that application of polyethylene glycol 1500 for synthesis of foams in amount from 0% to 20% w/w had an effect on reduction of brittleness and softening point, while the greater the increase in compressive strength the higher its content in foam composition was. Wastes from production of these foams were ground and subjected to glycolysis in diethylene glycol with the addition of ethanolamine and zinc stearate. Liquid brown products were obtained. Properties of the resulting products were defined in order to determine their suitability for synthesis of new foams. It was found that glycolysate 6 was the most suitable for reuse and its application in different amounts allowed us to prepare 4 new foams (nos. 25, 26, 27, and 28. Properties of foams prepared in this manner were determined and, on their basis, the suitability of glycolysates for production of rigid PUR-PIR foams was evaluated.
Dynamics of parallel robots from rigid bodies to flexible elements
Briot, Sébastien
2015-01-01
This book starts with a short recapitulation on basic concepts, common to any types of robots (serial, tree structure, parallel, etc.), that are also necessary for computation of the dynamic models of parallel robots. Then, as dynamics requires the use of geometry and kinematics, the general equations of geometric and kinematic models of parallel robots are given. After, it is explained that parallel robot dynamic models can be obtained by decomposing the real robot into two virtual systems: a tree-structure robot (equivalent to the robot legs for which all joints would be actuated) plus a free body corresponding to the platform. Thus, the dynamics of rigid tree-structure robots is analyzed and algorithms to obtain their dynamic models in the most compact form are given. The dynamic model of the real rigid parallel robot is obtained by closing the loops through the use of the Lagrange multipliers. The problem of the dynamic model degeneracy near singularities is treated and optimal trajectory planning for cro...
Rigid spherical particles in highly turbulent Taylor-Couette flow
Bakhuis, Dennis; Verschoof, Ruben A.; Mathai, Varghese; Huisman, Sander G.; Lohse, Detlef; Sun, Chao
2016-11-01
Many industrial and maritime processes are subject to enormous frictional losses. Reducing these losses even slightly will already lead to large financial and environmental benefits. The understanding of the underlying physical mechanism of frictional drag reduction is still limited, for example, in bubbly drag reduction there is an ongoing debate whether deformability and bubble size are the key parameters. In this experimental study we report high precision torque measurements using rigid non-deformable spherical particles in highly turbulent Taylor-Couette flow with Reynolds numbers up to 2 ×106 . The particles are made of polystyrene with an average density of 1.036 g cm-3 and three different diameters: 8mm, 4mm, and 1.5mm. Particle volume fractions of up to 6% were used. By varying the particle diameter, density ratio of the particles and the working fluid, and volume fraction of the particles, the effect on the torque is compared to the single phase case. These systematic measurements show that adding rigid spherical particles only results in very minor drag reduction. This work is financially supported by Netherlands Organisation for Scientific Research (NWO) by VIDI Grant Number 13477.
A method for measuring the inertia properties of rigid bodies
Gobbi, M.; Mastinu, G.; Previati, G.
2011-01-01
A method for the measurement of the inertia properties of rigid bodies is presented. Given a rigid body and its mass, the method allows to measure (identify) the centre of gravity location and the inertia tensor during a single test. The proposed technique is based on the analysis of the free motion of a multi-cable pendulum to which the body under consideration is connected. The motion of the pendulum and the forces acting on the system are recorded and the inertia properties are identified by means of a proper mathematical procedure based on a least square estimation. After the body is positioned on the test rig, the full identification procedure takes less than 10 min. The natural frequencies of the pendulum and the accelerations involved are quite low, making this method suitable for many practical applications. In this paper, the proposed method is described and two test rigs are presented: the first is developed for bodies up to 3500 kg and the second for bodies up to 400 kg. A validation of the measurement method is performed with satisfactory results. The test rig holds a third part quality certificate according to an ISO 9001 standard and could be scaled up to measure the inertia properties of huge bodies, such as trucks, airplanes or even ships.
Origami-Inspired Folding of Thick, Rigid Panels
Trease, Brian P.; Thomson, Mark W.; Sigel, Deborah A.; Walkemeyer, Phillip E.; Zirbel, Shannon; Howell, Larry; Lang, Robert
2014-01-01
To achieve power of 250 kW or greater, a large compression ratio of stowed-to-deployed area is needed. Origami folding patterns were used to inspire the folding of a solar array to achieve synchronous deployment; however, origami models are generally created for near-zero-thickness material. Panel thickness is one of the main challenges of origami-inspired design. Three origami-inspired folding techniques (flasher, square twist, and map fold) were created with rigid panels and hinges. Hinge components are added to the model to enable folding of thick, rigid materials. Origami models are created assuming zero (or near zero) thickness. When a material with finite thickness is used, the panels are required to bend around an increasingly thick fold as they move away from the center of the model. The two approaches for dealing with material thickness are to use membrane hinges to connect the panels, or to add panel hinges, or hinges of the same thickness, at an appropriate width to enable folding.
Directory of Open Access Journals (Sweden)
Wenguang Yang
2016-01-01
Full Text Available This paper proposes an improved rigid multibody model for the dynamic analysis of the planetary gearbox in a wind turbine. The improvements mainly include choosing the inertia frame as the reference frame of the carrier, the ring, and the sun and adding a new degree of freedom for each planet. An element assembly method is introduced to build the model, and a time-varying mesh stiffness model is presented. A planetary gear study case is employed to verify the validity of the improved model. Comparisons between the improvement model and the traditional model show that the natural characteristics are very close; the improved model can obtain the right equivalent moment of inertia of the planetary gear in the transient simulation, and all the rotation speeds satisfy the transmission relationships well; harmonic resonance and resonance modulation phenomena can be found in their vibration signals. The improved model is applied in a multistage gearbox dynamics analysis to reveal the prospects of the model. Modal analysis and transient analysis with and without time-varying mesh stiffness considered are conducted. The rotation speeds from the transient analysis are consistent with the theory, and resonance modulation can be found in the vibration signals.
Directory of Open Access Journals (Sweden)
Soeprapto Gambiro
2017-01-01
Full Text Available Various types of reinforced concrete floors can be applied to building construction. The floor of the building can be made of cast in place or precast concrete. The floors should function as a rigid diaphragm, in order to distribute the lateral forces on the building frame. While the floor is made of precast concrete, especially those without overtopping, should be arranged in such a way to function as a diaphragm. In order for the precast slab can function as a diaphragm, the components must be connected to the building frame and between the component itself . Some of them are drag strut, boundary element (chord, transverse joint, collector and longitudinal joint. This paper will discuss the influence of the longitudinal joint shear key with some types. The test specimen is modeled as two HCS are mounted parallel to each other , then the both of HCS are combined with perimeter beams to obtain the same model with the actual conditions and simplify to execute. All models of the test specimen are made to represent the three types of shear key. The test specimen is loaded the shear force and observed the structure behavior and crack patterns.