Keyboard symbols
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You've seen tons of text symbols on Facebook, Myspace and YouTube. Special
characters rose to popularity along with social networking. Most text signs, like
♥
aren't really used in books and references, but are easily recognisable graphemes.
Main reasons why symbols are rising to prominence are that they convey same
meaning as words, but in a smaller space and they are well recognised among all
internet users across the globe independent of their language, culture or ethnicity.
Another reason is that they are often used as building blocks of text pictures to depict
different emotions, concepts, images and other stuff (✿◠‿◠) You can type symbols
right from your keyboard. I'm going to show you how. Also, if you want to check out
all the symbols you have in each of font you got installed on your computer, check
out Character Maps.
≧◔◡◔≦
Shortcut technique that works on Desktops and most Laptops running MS Windows.
You press Alt and, while holding it, type a code on Num Pad. It's very easy, but not
as practical for long-term usage as Shift States. Also, you can type many frequently
used symbols with this method, but not all like with Shift States.
Shift states
My Windows keyboard layout with symbolsWant to access symbols really fast
from your keyboard? Install my custom keyboard layout.
E̲n̲t̲i̲r̲e̲l̲y̲ free. Includes
source file, so you can edit it the way you want.
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Shift states for Windows symbols
Configure your keyboard layout in Windows so that you can type all additional
symbols you want as easy as any other text. Takes about 5-10 minutes to set things
up, but you'll be typing like a boss.
Character map
MS Windows Character map
CharMap allows you to view and use all characters and symbols available in all
fonts (some examples of fonts are "Arial", "Times New Roman", "Webdings")
installed on your computer.
Computer Screens Harder To Understand, Less Persuasive
WASHINGTON Students who read essays on a computer screen found the text
harder to understand, less interesting and less persuasive than students who read the
same essay on paper, a new study has found.
Researchers had 131 undergraduate students read two articles that had
appeared in Time magazine - some read from the magazine, some read the exact
same text after it had been scanned into a computer.
"We were surprised that students found paper texts easier to understand and
somewhat more convincing," said P. Karen Murphy, co-author of the study and
assistant professor of educational psychology at Ohio State University. "It may be
that students need to learn different processing abilities when they are attempting to
read computerized text."
Murphy said the results of this preliminary study cast doubt on the assumption
that computerized texts are essentially more interesting and, thus, more likely to
enhance learning.
"Given that there is such an emphasis on using computers in the classroom, this
study gives educators reason to pause and examine the supposed benefits associated
with computer use in classrooms," she said. "This study provides a first step toward
understanding how computers might influence the learning process."
Murphy conducted the study with Ohio State graduate students Joyce Long,
Theresa Holleran and Elizabeth Esterly. They presented their results Aug. 5 in
Washington at the annual meeting of the American Psychological Association.
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The study involved 64 men and 67 women, all undergraduates at Ohio State.
The students read two essays that had appeared in Time, one involving doctor-
assisted suicide for terminally ill patients and the other about school integration.
Before they read the essays, the students completed questionnaires analyzing
their knowledge and beliefs about the subjects in the texts.
After the readings, the students completed questionnaires that probed their
understanding of the essays and also asked them about how persuasive and
interesting they thought the essays were.
One-third of the students read the print essays and responded to the
questionnaires on paper. One-third read the essays on a computer and then responded
to the questionnaire on paper. The final third of participants read the essays on the
computer screens and responded to the questionnaire online.
The results showed that students in all three groups increased their knowledge
after reading the texts, and the beliefs of students in each group became more closely
aligned with the authors.
However, there were important differences, such as the fact that students who
read the essays on the computer screen found the texts more difficult to understand.
This was true regardless of how much computer experience the students reported.
"In some ways, this is surprising because the computerized essays were the
exact same text, presenting the exact same information," Murphy said. The
computerized texts even included the small picture that appeared in the print edition.
"There is no reason they should be harder to understand. But we think readers
develop strategies about how to remember and comprehend printed texts, but these
students were unable to transfer those strategies to computerized texts."
The students found the computerized texts less interesting than printed text,
which should be expected if they didn't understand the computerized versions as well,
she said.
Students who read the essays online also rated the authors as less credible and
the arguments as less persuasive. "Again, it may be that if these students did not
understand the message, they would not judge the author to be as credible and might
not find the arguments as persuasive."
There were no significant differences between the students who read the texts
online and responded to the questionnaires on paper, and those who read the online
texts and also responded to the questions online.
Murphy said that if the college students in this study had difficulty
understanding computerized text, such text may present additional hurdles for less
competent readers.
"We shouldn't make it more difficult for children to learn, which is why we
need to be careful about how we use computers in the classroom," she said.
"A lot of questions have to be answered before we continue further into making
computers part of the curriculum."
Story Source:
The above post is reprinted from materials provided by Ohio State University.
Computer operations.
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Much of the processing computers can be divided into two general types of
operation. Arithmetic procedures. Early computers performed mostly arithmetic
operations, which gave the false impression that only engineers and scientists could
benefit from computers .Of equal importance is the computers operations are
computations with numbers such as addition, subtraction, and other mathematical
ability to compare two values to determine if one is larger than, smaller than, or equal
to the other. This is called a logical operation .The comparison may take place
between numbers, letters, sounds, or even drawings The processingofthe computer is
based on the computer’sability to perform logical and arithmetical operations.
Instructions must be given to the computer to tell it how to process the data it
receives and the format needed for output and storage. The ability to follow the
program sets computers apart from most tools. However, new tools ranging from
typewriters to microwave ovens have embedded computers, or build-in computers
.An embedded computer can accept data to use several options in it’s program, but
the program itself cannot be changed. This makes these devices flexible and
convenient but not the embedded computers itself.
Curation by Algorithm
Tarleton Gillespie Social media and content-sharing platforms must regularly
make decisions about what can be said and done on their sites, extending centuries-
old debates about the proper boundaries of public expression into the digital era. But,
in addition, the particular ways in which these sites enforce these choices have their
own consequences. While some providers depend on editorially managing content, or
lean on their user community to govern for them, some are beginning to employ
algorithmic means of managing their archive, so offending content can be
procedurally and automatically removed, or kept from some users and not others.
Curation by algorithm raises new questions about what judgments are being made,
whose values are being inscribed into the technical infrastructure, and what a
dependence on these tools might mean for the contours of public discourse and users'
participation in it.
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4. Texts for physics in english for high school
1.
Physical quantities and measurements
Speaking
A physical quantity (or "physical magnitude") is a physical property of a
phenomenon, body, or substance, that can be quantified bymeasurement.
[1]
A physical
quantity can be expressed as the combination of a number – usually a real number –
and a unit or combination of units; for example, 1.6749275×10
−27
kg (the mass of the
neutron), or 299792458 metres per second (the speed of light). Physical quantities are
measured as 'nu' where n is the number and u is the unit. For example: A boy
measured the length of a room as 3m. Here 3 is the number and m(metre) is the unit.
3m can also be written as 300cm. This shows that n1u1 =n2u2. Almost all matters
have quantity.
2.
Mechanics
Kinematics
Kinematics is used in astrophysics to describe the motion of celestial bodies
and collections of such bodies. In mechanical engineering, robotics, and
biomechanics
[7]
kinematics is used to describe the motion of systems composed of
joined parts (multi-link systems) such as an engine, a robotic arm or the skeleton of
the human body.
The use of geometric transformations, also called rigid transformations, to
describe the movement of components of a mechanical system simplifies the
derivation of its equations of motion, and is central to dynamic analysis.
Kinematic analysis is the process of measuring the kinematic quantities used to
describe motion. In engineering, for instance, kinematic analysis may be used to find
the range of movement for a given mechanism, and working in reverse, using
kinematic synthesis used to design a mechanism for a desired range of motion.
[8]
In
addition, kinematics applies algebraic geometry to the study of the mechanical
advantage of a mechanical system or mechanism.
Dynamics
The study of dynamics falls under two categories: linear and rotational. Linear
dynamics pertains to objects moving in a line and involves such quantities as force,
mass/inertia,displacement (in units of distance), velocity (distance per unit time),
acceleration (distance per unit of time squared) and momentum (mass times unit of
velocity). Rotational dynamics pertains to objects that are rotating or moving in a
curved path and involves such quantities as torque, moment of inertia/rotational
inertia, angular displacement (in radians or less often, degrees), angular velocity
(radians per unit time), angular acceleration (radians per unit of time squared) and
angular momentum (moment of inertia times unit of angular velocity). Very often,
objects exhibit linear and rotational motion.
For classical electromagnetism, it is Maxwell's equations that describe the
dynamics. And the dynamics of classical systems involving both mechanics and
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electromagnetism are described by the combination of Newton's laws, Maxwell's
equations, and the Lorentz force.
Conservation law
In physics, a conservation law states that a particular measurable property of
an isolated physical system does not change as the system evolves over time. Exact
conservation laws include conservation of energy, conservation of linear momentum,
conservation of angular momentum, and conservation of electric charge. There are
also many approximate conservation laws, which apply to such quantities as
mass,parity, lepton number, baryon number, strangeness, hypercharge, etc. These
quantities are conserved in certain classes of physics processes, but not in all.
A local conservation law is usually expressed mathematically as a continuity
equation, a partial differential equation which gives a relation between the amount of
the quantity and the "transport" of that quantity. It states that the amount of the
conserved quantity at a point or within a volume can only change by the amount of
the quantity which flows in or out of the volume.
From Noether's theorem, each conservation law is associated with a symmetry
in the underlying physics.
Oscillation and Wave
The harmonic oscillator and the systems it models have a single degree of
freedom. More complicated systems have more degrees of freedom, for example two
masses and three springs (each mass being attached to fixed points and to each other).
In such cases, the behavior of each variable influences that of the others. This leads to
a coupling of the oscillations of the individual degrees of freedom. For example, two
pendulum clocks (of identical frequency) mounted on a common wall will tend to
synchronise. This phenomenon was first observed by Christiaan Huygens in 1665.
The apparent motions of the compound oscillations typically appears very
complicated but a more economic, computationally simpler and conceptually deeper
description is given by resolving the motion into normal modes.
More special cases are the coupled oscillators where energy alternates between
two forms of oscillation. Well-known is the Wilberforce pendulum, where the
oscillation alternates between an elongation of a vertical spring and the rotation of an
object at the end of that spring.
A single, all-encompassing definition for the term wave is not straightforward.
A vibration can be defined as a back-and-forthmotion around a reference value.
However, a vibration is not necessarily a wave. An attempt to define the necessary
and sufficient characteristics that qualify a phenomenon to be called a wave results in
a fuzzy border line.
The term wave is often intuitively understood as referring to a transport of
spatial disturbances that are generally not accompanied by a motion of the medium
occupying this space as a whole. In a wave, the energy of a vibration is moving away
from the source in the form of a disturbance within the surrounding medium (Hall
1980, p. 8). However, this motion is problematic for a standing wave (for example, a
wave on a string), where energy is moving in both directions equally, or for
electromagnetic (e.g., light) waves in a vacuum, where the concept of medium does
not apply and interaction with a target is the key to wave detection and practical
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applications. There are water waves on the ocean surface; gamma waves and light
waves emitted by the Sun; microwaves used in microwave ovens and in radar
equipment; radio waves broadcast by radio stations; and sound waves generated by
radio receivers, telephone handsets and living creatures (as voices), to mention only a
few wave phenomena.
It may appear that the description of waves is closely related to their physical
origin for each specific instance of a wave process. For example, acoustics is
distinguished fromoptics in that sound waves are related to a mechanical rather than
an electromagnetic wave transfer caused by vibration. Concepts such as mass,
momentum, inertia, orelasticity, become therefore crucial in describing acoustic (as
distinct from optic) wave processes. This difference in origin introduces certain wave
characteristics particular to the properties of the medium involved. For example, in
the case of air: vortices, radiation pressure, shock waves etc.; in the case of solids:
Rayleigh waves, dispersion; and so on....
Other properties, however, although usually described in terms of origin, may
be generalized to all waves. For such reasons, wave theory represents a particular
branch ofphysics that is concerned with the properties of wave processes
independently of their physical origin.
[1]
For example, based on the mechanical origin
of acoustic waves, a moving disturbance in space–time can exist if and only if the
medium involved is neither infinitely stiff nor infinitely pliable. If all the parts
making up a medium were rigidly bound, then they would all vibrate as one, with no
delay in the transmission of the vibration and therefore no wave motion. On the other
hand, if all the parts were independent, then there would not be any transmission of
the vibration and again, no wave motion. Although the above statements are
meaningless in the case of waves that do not require a medium, they reveal a
characteristic that is relevant to all waves regardless of origin: within a wave, the
phase of a vibration (that is, its position within the vibration cycle) is different for
adjacent points in space because the vibration reaches these points at different times.
3. Thermal Physics
Molecular physics
Molecular mechanics is one aspect of molecular modelling, as it refers to the
use of classical mechanics/Newtonian mechanics to describe the physical basis
behind the models. Molecular models typically describe atoms (nucleus and electrons
collectively) as point charges with an associated mass. The interactions between
neighbouring atoms are described by spring-like interactions (representing chemical
bonds) and van der Waals forces. The Lennard-Jones potential is commonly used to
describe van der Waals forces. The electrostatic interactions are computed based
onCoulomb's law. Atoms are assigned coordinates in Cartesian space or in internal
coordinates, and can also be assigned velocities in dynamical simulations. The atomic
velocities are related to the temperature of the system, a macroscopic quantity. The
collective mathematical expression is known as a potential function and is related to
the system internal energy (U), a thermodynamic quantity equal to the sum of
potential and kinetic energies. Methods which minimize the potential energy are
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known as energy minimization techniques (e.g., steepest descent and conjugate
gradient), while methods that model the behaviour of the system with propagation of
time are known as molecular dynamics.
This function, referred to as a potential function, computes the molecular
potential energy as a sum of energy terms that describe the deviation of bond lengths,
bond angles and torsion angles away from equilibrium values, plus terms for non-
bonded pairs of atoms describing van der Waals and electrostatic interactions. The set
of parameters consisting of equilibrium bond lengths, bond angles, partial charge
values, force constants and van der Waals parameters are collectively known as a
force field. Different implementations of molecular mechanics use different
mathematical expressions and different parameters for the potential function. The
common force fields in use today have been developed by using high level quantum
calculations and/or fitting to experimental data. The technique known as energy
minimization is used to find positions of zero gradient for all atoms, in other words, a
local energy minimum. Lower energy states are more stable and are commonly
investigated because of their role in chemical and biological processes. Amolecular
dynamics simulation, on the other hand, computes the behaviour of a system as a
function of time. It involves solving Newton's laws of motion, principally the second
law,
. Integration of Newton's laws of motion, using different integration
algorithms, leads to atomic trajectories in space and time. The force on an atom is
defined as the negative gradient of the potential energy function. The energy
minimization technique is useful for obtaining a static picture for comparing between
states of similar systems, while molecular dynamics provides information about the
dynamic processes with the intrinsic inclusion of temperature effects.
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