REGULAR VIRTUAL COORDINATE SYSTEM OF COORDINATES OVER THE FIELD OF MOVING VISUAL LANDMARKS

2020 ◽  
pp. 11-17
Author(s):  
T. A. Tikhomirova ◽  
G. T. Fedorenko ◽  
K. M. Nazarenko ◽  
E. S. Nazarenko
Keyword(s):  
Coordinate System ◽  
Random Structure ◽  
Quasi Equilibrium ◽  
Global Instability ◽  
Visual Landmarks ◽  
T Matrix ◽  
Grid Nodes ◽  
Special Case ◽  
Over Time ◽  
Virtual Coordinate

The problem objects tracing in respect to large sample of visual landmarks whose position, shape, and optical properties change over time is considered. A Regular Virtual Coordinate System (RVCS) based on visual landmarks triangulation is proposed. RVCS is created using a linear iterative algorithm to relax initial triangulation to the quasi equilibrium state – shagreen, in which the grid nodes are located close to centers of their surroundings. It is shown that shagreen has a dense boundary with strongly elongated cells and the central core with almost regular triangles. We proposed to use the shagreen core as a virtual barycentric mesh because its geometry is regular and resistant to random displacements of visual landmarks, while correctly mirror affinity transformations. The use of RVCS allows to minimize the amount of information for representing the object trajectory while maintaining the accuracy of its localization close to the maximum achievable when using all available landmarks. It is shown that due to its global instability of the shagreen with random structure the triangulations with less then 100 vertices should be relaxed by no more then T = 10 – 20 simple iterations. This process can be represented by single linear operator which in special case T = 2t is created by t matrix multiplications. In addition, shagreen indicates the smooth trend for rough landscape, which increases the reliability of the estimation of local normals.

The Special Case of Anesthesia

2019 ◽  
pp. 49-56
Author(s):  
Robert L. Wears ◽  
Kathleen M. Sutcliffe
Keyword(s):  
Medical Specialty ◽  
Clinical Safety ◽  
Complex Interactions ◽  
State Of Affairs ◽  
Special Case ◽  
Over Time

Anesthesia became the only medical specialty to undertake systematic and dramatic improvements in safety over time. Evidence suggests that this process began through the fortuitous engagement of engineers in anesthesia work, supported by respected leaders in the field. The goal was not simply to solve a problem. The aims were too deeply understand the nature of the technology, the work, and the complex interactions that take place in work as carried out. Oddly, healthcare more generally failed to emulate these efforts. This state of affairs may be attributed to the substantive influence of non-clinical safety scientists in anesthesia, and also to differences in widely accepted methodological and investigative research approaches.

An Evaluation of the Stereocinematographic Method to Estimate Fish Swimming Speed

1992 ◽  
Vol 49 (3) ◽  
pp. 523-531 ◽  
Author(s):  
Daniel Boisclair
Keyword(s):  
Coordinate System ◽  
Sample Size ◽  
Swimming Speed ◽  
Fish Swimming ◽  
Individual Fish ◽  
Precision And Accuracy ◽  
Over Time

I evaluated the precision and accuracy of the stereocinematographic (SCG) method for estimating fish swimming speed. The SCG method implements the differences in images recorded by two cameras to determine the position of a target in an x, y, z, coordinate system. Movements and speeds were determined using variations in the position of the targets over time. Movements of rulers [Formula: see text] estimated in the laboratory did not differ significantly from measured values. The accuracy of the SCG method in the field was assessed by comparing simultaneous estimates of the speed of the head and of the tail of individual fish observed in in situ enclosures. Differences between these descriptors of fish swimming were always < 2 body lengths (bl)∙s−1 and, on average, did not differ significantly from 0. Swimming speeds [Formula: see text] ranged from 0.6 to 20.7 cm∙s−1 (0.1–3.8 bl∙s−1). Speed variations between two consecutive 1-s intervals ranged from −23.9 cm∙s−1 (deceleration) to 23.6 cm∙s−1 (acceleration). Positioning fish at 1- to 6-s intervals tended to decrease the variance of swimming speed estimates. A sample size of 100–150 speeds per hour was sufficient to accurately describe fish swimming in an in situ enclosure.

scholarly journals Metric Characterizations ofα-Well-Posedness for a System of Mixed Quasivariational-Like Inequalities in Banach Spaces

2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
L. C. Ceng ◽  
Y. C. Lin
Keyword(s):  
Banach Spaces ◽  
Existence And Uniqueness ◽  
Equilibrium Problems ◽  
Uniqueness Of Solution ◽  
Quasi Equilibrium ◽  
Well Posedness ◽  
Special Case

The purpose of this paper is to investigate the problems of the well-posedness for a system of mixed quasivariational-like inequalities in Banach spaces. First, we generalize the concept ofα-well-posedness to the system of mixed quasivariational-like inequalities, which includes symmetric quasi-equilibrium problems as a special case. Second, we establish some metric characterizations ofα-well-posedness for the system of mixed quasivariational-like inequalities. Under some suitable conditions, we prove that theα-well-posedness is equivalent to the existence and uniqueness of solution for the system of mixed quasivariational-like inequalities. The corresponding concept ofα-well-posedness in the generalized sense is also considered for the system of mixed quasivariational-like inequalities having more than one solution. The results presented in this paper generalize and improve some known results in the literature.

scholarly journals Derivation of the Quantum Vlasov Equation and Dispersion Relation of a Relativistic Electron Gas

1967 ◽  
Vol 22 (6) ◽  
pp. 869-872 ◽  
Author(s):  
D. BlSkamp
Keyword(s):  
Dispersion Relation ◽  
Relativistic Electron ◽  
Vlasov Equation ◽  
Thermal Equilibrium ◽  
Electron Gas ◽  
Quasi Equilibrium ◽  
Electron Positron ◽  
The One ◽  
Special Case ◽  
Quantum Vlasov Equation

The selfconsistent field equation (VLASOV equation) is derived for the one-particle WIGNER function of a relativistic electron-positron gas. From the linearized form we obtain the dispersion relation for any quasi-equilibrium state, which for the special case of thermal equilibrium has already been derived by TSYTOVICH 1.

Language Attrition as a Special Case of Processing Change

2019 ◽  
pp. 72-87
Author(s):  
Michael Sharwood Smith
Keyword(s):  
Cognitive Processing ◽  
Language Processing ◽  
Language Attrition ◽  
Change Over Time ◽  
Knowledge Representations ◽  
Language Representation ◽  
Research Findings ◽  
Processing Mechanisms ◽  
Special Case ◽  
Over Time

This chapter examines the ways in which language processing has been treated in both the attrition and the acquisition literature, embedding the discussion within a wider view of how knowledge representations change over time. Even where particular types of language representation are understood to be governed by principles unique to language, attrition must be seen as a manifestation of general cognitive processing principles as well. For this you need a framework that allows many different strands of research to be carried out within a single, detailed, workable, unified account. This can lead to richer and more reliable explanations of research findings. The chapter will employ such a framework to examine language attrition with regard to 1) the nature and operation of language processing mechanisms; 2) how these relate to other types of cognitive processing; 3) how processing acts as the driver of representational change.

Introits and ingressae – Milan and Rome: the elaboration of chant melodies, the operation of musical memory

2010 ◽  
Vol 19 (2) ◽  
pp. 89-122 ◽  
Author(s):  
Terence Bailey
Keyword(s):  
Eleventh Century ◽  
Musical Culture ◽  
Firm Basis ◽  
The Alps ◽  
Precise Relationship ◽  
Relationship Of ◽  
Musical Memory ◽  
Special Case ◽  
Over Time ◽  
Old Roman

ABSTRACTAlthough it has always been plain to see that the Milanese and Roman Mass shared many texts, that the melodies were also shared has gone largely unnoticed, or at any rate undemonstrated, except in the special case of the few offertory chants with wider concordances in Franco-Roman, Milanese and Visigothic books. This article takes up the particular case of the Roman and Milanese entrance antiphons: first, the circumstances of the importation of the Roman introits into the Ambrosian Mass; and, second, the precise relationship of the Ambrosian and Franco-Roman (Gregorian) melodies. It has long been understood that chants of the Old Roman repertory provide a firm basis for an understanding of the changes, inevitable over time, in an orally transmitted repertory. It emerges that the Ambrosian melodies, transcribed in neumes in about the middle of the eleventh century, offer a second opportunity for a sondage. This other, unsuspected, version of the chants, miraculously preserved and stabilised north of the Alps in the ninth and tenth centuries also allows for convincing demonstrations of the musical procedures employed in the elaboration of the melodies and in their adaptation to different texts. And not least, the isolation of what is shared between versions notated at a distance of centuries give us the basis of an objective estimation of the effectiveness of musical memory in a musical culture that did not rely on notation.

scholarly journals Morphological dynamics of an englacial channel

2016 ◽  
Vol 20 (7) ◽  
pp. 2947-2964 ◽  
Author(s):  
Geir Vatne ◽  
Tristram D. L. Irvine-Fynn
Keyword(s):  
Quasi Equilibrium ◽  
Upstream Migration ◽  
Potential Significance ◽  
Flow Paths ◽  
Ice Dynamics ◽  
Channel Form ◽  
Rapid Transition ◽  
Dominant Process ◽  
Over Time

Abstract. Despite an interest in the hydraulic functioning of supraglacial and englacial channels over the last 4 decades, the processes and forms of such ice-bounded streams have remained poorly documented. Recent glaciological research has demonstrated the potential significance of so-called "cut-and-closure" streams, where englacial or subglacial flow paths are created from the long-term incision of supraglacial channels. These flow paths are reported to exhibit step-pool morphology, comprising knickpoints and/or knickzones, exaggerated in dimensions in comparison to supraglacial channels. However, little is known of the development of such channels' morphology. Here, we examine the spatial organisation of step pools and the upstream migration of steps, many of which form knickzones, with repeated surveys over a 10-year period in an englacial conduit in cold-based Austre Brøggerbreen, Svalbard. The observations show upstream step recession to be the dominant process for channel evolution. This is paralleled by an increase in average step height and conduit gradient over time. Characteristic channel-reach types and step-riser forms are consistently observed in each of the morphological surveys reported. We suggest that the formation of steps has a hydrodynamic origin, where step-pool geometry is more efficient for energy dissipation than meanders. The englacial channel system is one in rapid transition towards a quasi-equilibrium form within a decadal timescale. The evolution and recession of knickzones reported here result in the formation of a 37 m deep moulin shaft, suggesting that over time an incising supraglacial channel may evolve towards an englacial channel form exhibiting a stable end-point characterised by a singular vertical descent, which potentially can reach the glacier bed. This challenges the prevailing notions that crevasses or hydrofractures are needed to form deep moulins. Our observations highlight the need to further examine the adjustment processes in cut-and-closure channels to better understand their coupling to supraglacial meltwater sources and potential significance in cold-based glacier hydrology and ice dynamics.

scholarly journals On Stress-Strength Reliability with a Time-Dependent Strength

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Serkan Eryilmaz
Keyword(s):  
Stochastic Process ◽  
Stochastic Ordering ◽  
Random Variable ◽  
Time Dependent ◽  
Special Case ◽  
Weibull Process ◽  
Over Time

The study of stress-strength reliability in a time-dependent context needs to model at least one of the stress or strength quantities as dynamic. We study the stress-strength reliability for the case in which the strength of the system is decreasing in time and the stress remains fixed over time; that is, the strength of the system is modeled as a stochastic process and the stress is considered to be a usual random variable. We present stochastic ordering results among the lifetimes of the systems which have the same strength but are subjected to different stresses. Multicomponent form of the aforementioned stress-strength interference is also considered. We illustrate the results for the special case when the strength is modeled by a Weibull process.

scholarly journals An Efficient Bypassing Void Routing Algorithm for Wireless Sensor Network

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Xunli Fan ◽  
Feifei Du
Keyword(s):  
Wireless Sensor Network ◽  
Sensor Network ◽  
Geographic Routing ◽  
Transmission Delay ◽  
Wireless Sensor ◽  
Delivery Ratio ◽  
Random Structure ◽  
Control Packet ◽  
Coordinate Mapping ◽  
Virtual Coordinate

Since the sensor node’s distribution in a wireless sensor network (WSN) is irregular, geographic routing protocols using the greedy algorithm can cause local minima problem. This problem may fail due to routing voids and lead to failure of data transmission. Based on the virtual coordinate mapping, this paper proposes an efficient bypassing void routing protocol to solve the control packet overhead and transmission delay in routing void of WSN, which is called EBVRPVCM. The basic idea is to transfer the random structure of void edge to a regular one through mapping the coordinates on a virtual circle. In EBVRPVCM, some strategies, executed in different regions, are selected through virtual coordinates to bypass routing void efficiently. The regular edge is established by coordinate mapping that can shorten the average routing path length and decrease the transmission delay. The virtual coordinate mapping is not affected by the real geographic node position, and the control packet overhead can be reduced accordingly. Compared with RGP and GPSR, simulation results demonstrate that EBVRPVCM can successfully find the shortest routing path with higher delivery ratio and less control packet overhead and energy consumption.

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