Teleconnections

2006 ◽  
Author(s):  
Huug van den Dool
Keyword(s):  
System Analysis ◽  
Severe Weather ◽  
The Other ◽  
Single Variable ◽  
Long Distance ◽  
Weather System ◽  
Daily Data ◽  
The Crimea ◽  
Time Lagged ◽  
A Chain

Mankind has long been intrigued by the possibility that weather in one location is related to weather somewhere else, especially somewhere very far away. The fascination may be mostly related to possible predictions that could be based on such relationships. The severe weather that harmed the British Army in the Crimea in November 1854 (Lindgrén and Neumann 1980) was due to a weather system moving across Europe, suggesting it could have been anticipated from observations upstream. It took analyses of many surface weathermaps, an activity starting around 1850, to see how weather systems have certain horizontal dimensions, thousands of kilometers in fact, and move around in semisystematic ways. It thus followed that, in a transient sense, the weather at two places can be related, and in a time-lagged sense that weather observed at one (or more) places serves as a predictor for weather at other locations. The other reason for fascination with teleconnection might be called “system analysis”. The idea that given an impulse at some location (“input”) a reaction can be expected thousands of miles away (the “output”) through a chain of events, is intriguing and should tell us about the workings of the system. It is akin to an engineer testing electronic equipment. Unfortunately, Nature is not a laboratory experiment where we can organize these impulses. Only by systematically observing what Nature presents us with, may we dare to search for teleconnections in some aggregate way. The word teleconnection suggests a connection at long distance, but a stricter definition requires some thought and pruning down of endless possibilities. We need to make choices about (a) simultaneous vs time-lagged teleconnections, (b) correlations vs other measures of “connection”, (c) transient vs standing teleconnections, (d) teleconnections in filtered data (e.g. seasonal means) vs unfiltered instantaneous (e.g. daily) data, and (e) one or more variables. On (a), (b) and (e) our choice in this chapter is simultaneous, use of linear correlation (except in section 4.3 where other measures of teleconnection are discussed), and a single variable respectively. On possibilities (c) and (d) we keep our options open.

scholarly journals IOT - Overview, Implementation and Upcoming Challenges

2020 ◽  
pp. 215-218
Author(s):  
Sativilla Mohan Kumar ◽  
Advin Manhar
Keyword(s):  
Internet Of Things ◽  
Environmental Monitoring ◽  
Data Integrity ◽  
The Other ◽  
The Internet ◽  
Long Distance ◽  
Physical Objects ◽  
A Chain ◽  
The Internet Of Things

IoT is a chain of Physical Objects that are installed with sensors, software, and other technologies for the goal of connecting and transferring data with other devices and systems over the Internet. In many research, it has been found that the data and communication between the Internet of Things are insecure. Also, the data which is transferred from one end to the other end is accessible for a shorts distance. A discovered protocol for Data Integrity in IoT communication. A protocol for providing an environmental monitoring solution and a system that facilitates the practical experimentation of the IoT solutions. After the data is secured with the protocols and it has received an environment for the experiments, the message has to be sent over a long distance.

Correlational Methods for Analysis of Dance Movements

2011 ◽  
Vol 29 (supplement) ◽  
pp. 283-304 ◽  
Author(s):  
Timothy R. Brick ◽  
Steven M. Boker
Keyword(s):  
Motion Capture ◽  
Mirror Symmetry ◽  
Cross Correlation ◽  
The Other ◽  
Free Form ◽  
Motion Capture Data ◽  
Complex Interactions ◽  
Dance Movements ◽  
Time Lagged ◽  
Insight Into

Among the qualities that distinguish dance from other types of human behavior and interaction are the creation and breaking of synchrony and symmetry. The combination of symmetry and synchrony can provide complex interactions. For example, two dancers might make very different movements, slowing each time the other sped up: a mirror symmetry of velocity. Examining patterns of synchrony and symmetry can provide insight into both the artistic nature of the dance, and the nature of the perceptions and responses of the dancers. However, such complex symmetries are often difficult to quantify. This paper presents three methods – Generalized Local Linear Approximation, Time-lagged Autocorrelation, and Windowed Cross-correlation – for the exploration of symmetry and synchrony in motion-capture data as is it applied to dance and illustrate these with examples from a study of free-form dance. Combined, these techniques provide powerful tools for the examination of the structure of symmetry and synchrony in dance.

scholarly journals XXIII.—On the Disruptive Discharge of Electricity: An Experimental Thesis for the Degree of Doctor of Science, Department A

1878 ◽  
Vol 28 (2) ◽  
pp. 633-671 ◽  
Author(s):  
Alexander Macfarlane
Keyword(s):  
Copper Wire ◽  
Late Summer ◽  
The Other ◽  
Straight Line ◽  
Summer Session ◽  
The Difference ◽  
A Chain ◽  
The One ◽  
Metallic Parts ◽  
The University

The experiments to which I shall refer were carried out in the physical laboratory of the University during the late summer session. I was ably assisted in conducting the experiments by three students of the laboratory,—Messrs H. A. Salvesen, G. M. Connor, and D. E. Stewart. The method which was used of measuring the difference of potential required to produce a disruptive discharge of electricity under given conditions, is that described in a paper communicated to the Royal Society of Edinburgh in 1876 in the names of Mr J. A. Paton, M. A., and myself, and was suggested to me by Professor Tait as a means of attacking the experimental problems mentioned below.The above sketch which I took of the apparatus in situ may facilitate tha description of the method. The receiver of an air-pump, having a rod capable of being moved air-tight up and down through the neck, was attached to one of the conductors of a Holtz machine in such a manner that the conductor of the machine and the rod formed one conducting system. Projecting from the bottom of the receiver was a short metallic rod, forming one conductor with the metallic parts of the air-pump, and by means of a chain with the uninsulated conductor of the Holtz machine. Brass balls and discs of various sizes were made to order, capable of being screwed on to the ends of the rods. On the table, and at a distance of about six feet from the receiver, was a stand supporting two insulated brass balls, the one fixed, the other having one degree of freedom, viz., of moving in a straight line in the plane of the table. The fixed insulated ball A was made one conductor with the insulated conductor of the Holtz and the rod of the receiver, by means of a copper wire insulated with gutta percha, having one end stuck firmly into a hole in the collar of the receiver, and having the other fitted in between the glass stem and the hollow in the ball, by which it fitted on to the stem tightly. A thin wire similarly fitted in between the ball B and its insulating stem connected the ball with the insulated half ring of a divided ring reflecting electrometer.

scholarly journals The linkage of sugar phosphate polymer to peptidoglycan in walls of Micrococcus sp. 2102

1978 ◽  
Vol 169 (2) ◽  
pp. 329-336 ◽  
Author(s):  
J Heptinstall ◽  
J Coley ◽  
P J Ward ◽  
A R Archibald ◽  
J Baddiley
Keyword(s):  
Staphylococcus Aureus ◽  
Alkaline Hydrolysis ◽  
The Other ◽  
Muramic Acid ◽  
Sugar Phosphate ◽  
Glycerol Phosphate ◽  
Homogeneous Product ◽  
A Chain

1. Protein-free walls of Micrococcus sp. 2102 contain peptidoglycan, poly-(N-acetylglucosamine 1-phosphate) and small amounts of glycerol phosphate. 2. After destruction of the poly-(N-acetylglucosamine 1-phosphate) with periodate, the glycerol phosphate remains attached to the wall, but can be removed by controlled alkaline hydrolysis. The homogeneous product comprises a chain of three glycerol phosphates and an additional phosphate residue. 3. The poly-(N-acetylglucosamine 1-phosphate) is attached through its terminal phosphate to one end of the tri(glycerol phosphate). 4. The other end of the glycerol phosphate trimer is attached through its terminal phosphate to the 3-or 4-position of an N-acetylglucosamine. It is concluded that the sequence of residues in the sugar 1-phosphate polymer-peptidoglycan complex is: (N-acetylglucosamine 1-phosphate)24-(glycerol phosphate)3-N-acetylglucosamine 1-phosphate-muramic acid (in peptidoglycan). Thus in this organism the phosphorylated wall polymer is attached to the peptidoglycan of the wall through a linkage unit comprising a chain of three glycerol phosphate residues and an N-acetylglucosamine 1-phosphate, similar to or identical with the linkage unit in Staphylococcus aureus H.

NUMERICAL ANALYSIS OF RANDOM DRIFT IN A CLINE

Genetics ◽  
1980 ◽  
Vol 94 (2) ◽  
pp. 497-517
Author(s):  
Thomas Nagylaki ◽  
Bradley Lucier
Keyword(s):  
Natural Populations ◽  
The Other ◽  
Random Genetic Drift ◽  
Gene Frequencies ◽  
Random Drift ◽  
Linear Habitat ◽  
Asymptotic Formulae ◽  
A Chain ◽  
Average Position ◽  
Uniform Population

ABSTRACT The equilibrium state of a diffusion model for random genetic drift in a cline is analyzed numerically. The monoecious organism occupies an unbounded linear habitat with constant, uniform population density. Migration is homogeneouq symmetric and independent of genotype. A single diallelic locus with a step environment is investigated in the absence of dominance and mutation. The flattening of the expected cline due to random drift is very slight in natural populations. The ratio of the variance of either gene frequency to the product of the expected gene frequencies decreases monotonically to a nonzero constant. The correlation between the gene frequencies at two points decreases monotonically to zero as the separation is increased with the average position fixed; the decrease is asymptotically exponential. The correlation decreases monotonically to a positive constant depending on the separation as the average position increasingly deviates from the center of the cline with the separation fixed. The correlation also decreases monotonically to zero if one of the points is fixed and the other is moved outward in the habitat, the ultimate decrease again being exponential. Some asymptotic formulae are derived analytically.—The loss of an allele favored in an environmental pocket is investigated by simulating a chain of demes exchanging migrants, the other assumptions being the same as above. For most natural populations, provided the allele would be maintained in the population deterministically, this process is too slow to have evolutionary importance.

scholarly journals Design and Fabrication of Small Vertical-Take-Off-Landing Unmanned Aerial Vehicle

2018 ◽  
Vol 152 ◽  
pp. 02023 ◽  
Author(s):  
Yasir Ashraf Abd Rahman ◽  
Mohammad Taghi Hajibeigy ◽  
Abdulkareem Shafiq Mahdi Al-Obaidi ◽  
Kean How Cheah
Keyword(s):  
Design Methodology ◽  
The Other ◽  
Long Distance ◽  
Open Spaces ◽  
Flight Tests ◽  
Flight Range ◽  
Horizontal Flight ◽  
Vtol Uav ◽  
Aerial Vehicle ◽  
Horizontal Thrust

Modern UAVs available in the market have well-developed to cater to the countless field of application. UAVs have their own limitations in terms of flight range and manoeuvrability. The traditional fixed-wing UAVs can fly for long distance but require runways or wide-open spaces for take-off and landing. On the other hand, the more trending multirotor UAVs are extremely manoeuvrable but cannot be used for long-distance flights because of their slower speeds and relatively higher consumption of energy. This study proposed the implementation of hybrid VTOL UAV which has the manoeuvring advantage of a multirotor UAV while having the ability to travel fast to reach a further distance. The design methodology and fabrication method are discussed extensively which would be followed by a number of flight tests to prove the concept. The proposed UAV would be equipped with quadcopter motors and a horizontal thrust motor for vertical and horizontal flight modes respectively.

Making Music, Building Roads

2021 ◽  
pp. 62-72
Author(s):  
Penny Harvey
Keyword(s):  
The Other ◽  
British Broadcasting Corporation ◽  
Long Distance ◽  
Music Making ◽  
Growing Body ◽  
Engineered Systems ◽  
The One ◽  
Relational Capacities ◽  
The Relationship ◽  
Sixtieth Anniversary

This chapter explores how the analyses of audible infrastructures presented in this volume connect to the established and growing body of literature on civic infrastructures from scholars in the humanities and social sciences. There are clearly convergent interests between those who work on roads, water, and energy systems, on the one hand, and those who study the production, circulation, and reproduction of sound, on the other. To analyze the materialities of music making, as with civic infrastructures, is to investigate the relational capacities of the materials from which things are made, the diverse types of labor through which these materials become integral to their emergent forms, and the uneven distribution of access to the wider structures that underpin the circulation and reproduction of such forms. In particular, the chapter focuses on how the relationship between the hardware of engineered systems and the software of sociality creates new possibilities for thinking about the politics of infrastructure. The chapter explores these resonances between audible and civic infrastructures by considering the M1 Symphony, a work commissioned by the British Broadcasting Corporation to mark the sixtieth anniversary of the opening of Britain’s first long-distance motorway. The example provokes reflection on the relationship between media and infrastructure, between composition and improvisation, and between ontological experiment and artful design.

Making deeper insights part 2

2021 ◽  
pp. 247-270
Author(s):  
Owen L. Petchey ◽  
Andrew P. Beckerman ◽  
Natalie Cooper ◽  
Dylan Z. Childs
Keyword(s):  
Data Analysis ◽  
Descriptive Statistics ◽  
The Other ◽  
Single Variable ◽  
Individual Variables

In the previous chapter we looked at individual variables; however, a sample may involve more than one variable. Moreover, data analysis is usually concerned with the relationships among two or more variables. These relationships might involve the same (e.g. numeric versus numeric) or different (e.g. numeric versus categorical) types of variable. In either case, we need to understand how the values of one variable relate to and/or depend on those of the other. Just as with single-variable analyses, we use both descriptive statistics and graphical summaries to explore such relationships. This chapter focuses on associations between variables. An association is any relationship between two variables that makes them dependent, i.e. knowing the value of one variable gives us some information about the possible values of the second variable. The main goal of this chapter is to show how to use descriptive statistics and visualizations to explore associations among different kinds of variables.

Influence of Hopf Bifurcation Dynamics on Conduction Failure of Action Potentials Along Nerve C-Fiber

2019 ◽  
Vol 29 (07) ◽  
pp. 1950093 ◽  
Author(s):  
Xinjing Zhang ◽  
Huaguang Gu
Keyword(s):  
Hopf Bifurcation ◽  
Coupling Strength ◽  
The Other ◽  
Dimensional Parameter ◽  
External Stimulation ◽  
C Fiber ◽  
Current Threshold ◽  
Stimulation Period ◽  
Conduction Failure ◽  
A Chain

Contrary to faithful conduction of every action potential or spike along the axon, some spikes induced by the external stimulation with a high frequency at one end of the unmyelinated nerve fiber (C-fiber) disappear during the conduction process to the other end, which leads to conduction failure. Many physiological functions such as information coding or pathological pain are involved. In the present paper, the dynamic mechanism of the conduction failure is well interpreted by two characteristics of the focus near Hopf bifurcation of the Hodgkin–Huxley (HH) model. One is that the current threshold to evoke a spike from the after-potential corresponding to the focus exhibits damping oscillations, and the other is that the damping oscillations exhibit an internal period. A chain network model composed of HH neurons and stimulated by the external periodic stimulation is used to stimulate C-fiber. In the two-dimensional parameter space of the stimulation period and coupling strength, the conduction failure appears for the coupling strength lower than that of the faithful conduction, which is due to some maximal values of the coupling current for low coupling strength not being strong enough to evoke spikes, and the coupling strength threshold between the faithful conduction and conduction failure exhibiting damping oscillations with respect to the stimulation period, due to the damping oscillations of the current threshold. The damping oscillations of the coupling strength exhibit close correlations to those of the current threshold. The coupling strength for the conduction failure exhibits maximal values as the stimulation period is approximated to 1-, 2-, 3- or 4-times of the internal period and the maximal values decrease with increasing stimulation period. In addition, the correspondence between the simulation results and the previous experimental observations is discussed. The results present deep insights into the dynamics of the conduction failure with Hopf bifurcation and are helpful to investigate the influence of other modulation factors on the conduction failure.

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