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Файл:English for Innovatics. Часть 1. Учебное пособие
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диск, представляю вам их сравнение, чтобы помочь принять
решение.
10. Разница между внутренними и внешними жесткими
дисками:
11. Есть много моментов, которые нужно учесть при выборе
нового жесткого диска, но сначала вы должны решить,
внутренний или внешний жесткий диск вам нужен.
12. Различия между ними характеризуются их функциями.
13.Сравнение внутренних внешних жестких дисков:
быстродействие и доступная скорость передачи данных,
нужно сравнить два показателя: скорость доступа и скорость
передачи данных внутренних и внешних жестких дисков.
14. Различия между внутренними и внешними жесткими
дисками в портативности и стоимости.
15. При сравнении внутреннего и внешнего жесткого диска
выигрывает портативность.
16. Для пользователей, которым необходимо иметь при себе
резервное копирование данных регулярно, внешний жесткий
диск является самым лучшим выбором.
17. Выбирайте высокую скорость внешнего жесткого диска и
большой объем кэша, который будет обеспечивать вам
высокую скорость. USB и Firewire интерфейс позволяет легко
подключить и пользоваться на любом компьютере или
внешнем жестком диске, доступ к информационной панели.
18. Зато через внутренний жесткий диск это будет сложно.
19. Что касается стоимости, внутренний жесткий диск,
конечно, дешевле чем внешние накопители.
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20. Вы должны доплатить за портативность.
21. Если вы ищете дешевый дополнительный объем памяти,
выбирайте внутренний жесткий диск, но если цена не является
проблемой, переходите на внешний жесткий диск.
22. Одно из новшеств, которые быстро оставляют позади
традиционные электромеханические жесткие диски
твердотельных накопителей, основано на NANО флэшпамяти. Хотя это и дороговато для жестких дисков, но это
лучше, чем традиционные накопители любого типа.
Text C
The Present and Future of 3D
The Beginning of the 3D Era and the Boom Phenomenon
2010 has been called the beginning of the 3D era, a year in which
the term 3D frequently appeared in the media. Here, I use 3D to
mean three-dimensional images, or to give them their proper name,
stereoscopic images, reproduced to appear in front of or behind the
screen. The word stereoscopic was coined by the inventor of the
stereoscope, Sir Charles Wheatstone, who first used the term in a
paper published in 1838. It derives from the Greek words stereos,
meaning solid, and scope, meaning viewing instrument.
The phenomenon of periodic booms in 3D is often pointed
out. These were mainly 3D movie booms that occurred in the
1950s and 1980s, and the present day is sometimes referred to as
the third boom. The fact that 3D has until now never developed
beyond a temporary fad is an indication of the difficulty in
popularizing it. Nevertheless, the repeated appearance of such
booms does suggest that 3D is a kind of dream technology for
human beings. Here I would like to mention the characteristic
ripple effect of present day 3D. The rapid development outside the
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film industry of 3D-compatible TVs, game consoles and mobile
devices currently being announced and released by various
manufacturers has exceeded the expectations of most researchers
such as myself, as well as industry related people.
Issues of Present Day 3D
Although the spread of 3D is expected to result in the creation of
new industries and culture, it is still uncertain what the merits and
added value will be for users. When asked, “What is the advantage
of 3D movies or TV?” it is not enough to simply answer that
“things leap out of or into the screen”. Scientific verification of
whether 3D can really convey different sensations than 2D, or of
what elements of 3D people find appealing, is urgently required so
that the current boom does not turn into just another temporary fad.
At our laboratory, we have been conducting an
experimental study of current 3D issues as they relate to the user
experience. From Figure 1 we can see that the line of sight is
concentrated mostly on people, and especially faces, when
watching a movie in 2D. Figure 2 is the result when viewing the
same movie in 3D. Here we see that the line of sight is
concentrated not only on people’s faces but also on the objects in
the foreground. To clarify the cause of such a distinctive
difference, we have performed a range of detailed analyses,
especially of the link with the spatial construction of visual data.
Initiatives toward the Future of 3D
While tackling the present day tasks of explaining viewer
recognition and emotional aspects, our laboratory is also facing the
challenge of looking to the future of 3D. One such direction is new
applications of 3D. An example of this is three-dimensional
character blocks for literacy learning developed through joint
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research with the Division of Developmental Neuropsychology at
the National Center for Child Health and Development. The
intention is to utilize spatial reasoning capacity in literacy learning
by adding information of depth according to the stroke order of a
character to its ordinary two-dimensional shape. Such a conceptual
shift from representing real shapes three-dimensionally to
envisioning a specific effect and venturing to express it threedimensionally could produce an unprecedented demand for 3D.
Another direction we have taken relates to the extension
towards perceptual experience through 3D representation other
than vision. Figure 3 shows an example of this, a tactile behavioral
illusion system. By combining 3D and tactile stimulation based on
certain measurements, this system enables people to experience
sensations that have not actually been triggered. Specifically, we
can create an illusion related to bodily sensation, a feeling that a
stationary object touching one’s hand is moving across the surface
of that hand. Such a shift in awareness from a single sense to the
integration of multiple senses, or in other words, from vision to
brain function, could be vital in shaping the 3D-based media of the
next generation.
The desire to see remote things or to present them so that
they can be seen is a fundamental trait in human beings. That is to
say, interest in and expectations for 3D are perfectly natural, and so
the future of 3D also seems linked, to some extent, to human
potential.
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Lesson 3
Text A
Artificial Intelligencе
Artificial intelligence (AI) is invading the world. In the 90s
and early 21st century it achieved its greatest success. There are
more and more jobs which humans leave to robots such as
exploring another planet, defusing bombs, exploring inside a
volcano or just doing boring household chores like cleaning.
Computers can perform a lot of functions: they can control cars
and planes, give us the news, play chess and football or compose
music. Many factory jobs are performed by industrial robots
nowadays. It has led to cheaper production of various goods,
including automobiles and electronics. Industrial robots have little
resemblance to a human being.
Artificial intelligence is successfully used a medical
diagnosis, stock trading, robot control, law, scientific discovery
and toys. Industrial robots are also used for packaging of
manufactured goods, transporting goods around warehouses or
hospitals or removing tiny electronic components with great
accuracy, speed and reliability. Robots can move around, sense and
manipulate their environment, predict the actions of others and
exhibit intelligent behavior. Scientists are interested in designing
robots that resemble a human.
The question may arise whether robots are our best friends
or are they dangerous. Some futurists believe that artificial
intelligence will fundamentally transform society. Ray Kurzweil
has calculated that desktop computers will have the same
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processing power as human brains by 2029. And by 2045 artificial
intelligence will have reached a point where it is able to improve
itself. Many people fear that highly intelligent robots may take
over and destroy the human race.
But there are some reasons to worry about robots. The use
of robots in industry leads to unemployment as many jobs are
performed by machines. Besides industrial robots can be dangerous
and cause harm to human workers. So much attention must be paid
to security.
Many large companies have created robots which can
perform specific functions in the manner of a man. Here are some
of them:
First, Hitachi created its second humanoid robot EMIEW2
in 2008. This robot weighs 13kg and can move on wheels
as well as two legs. The robot is 80cm tall and it has 14
microphones which enable it to recognize human voice and
sounds. The robot can distinguish voices even when three
people are speaking at the same time and it can recognize
voices spoken as far as 2m away.
The second robot is called ASIMO that is (Advanced Step in
Innovative Mobility). It is a humanoid robot created by Honda
Motor Company. The robot is 130 cm tall and weighs 54
kilograms. It can walk or run on two feet at speeds up to 6 km/h.
The robot can perform various functions. For example it can follow
the movements of people with its camera, follow a person, or greet
a person. The robot can also sense the environment
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Text В
1. Crystallizing the switch to Hydrogen
Hydrogen gas is an almost infinitely inexhaustible fuel source
that emits only clean water during combustion. Switching from
hydrocarbon-based transportation to systems powered by state-ofthe-art fuel cells therefore seems a natural choice, but numerous
obstacles have kept this technology confined to laboratories. A
prime example is the problem of on-board hydrogen storage for
vehicles: because ambient hydrogen gas is roughly 10,000 times
less dense than gasoline, it would require impractically large tanks
to obtain comparable mileage.
Compressing hydrogen gas or liquefying it at -250 °C are two ways
to increase its energy content by volume. However, chemists are
developing a more attractive strategy using specially designed
compounds, called metal hydride clusters, to produce high
hydrogen-storage densities without extreme temperatures or
pressures. The metal atoms within these molecules bind to large
numbers of hydrogen atoms, producing a solid that can reversibly
add or remove hydrogen using mild heating or cooling.
Now, Zhaomin Hou from the RIKEN Advanced Science
Institute in Wako and an international team of colleagues have
isolated a new class of ‘heterometallic’ hydride clusters that may
spur development of lighter and longer-lived fuel cell devices. By
incorporating multinuclear rare-earth metals into their compounds,
the team has produced the first high-density storage molecules that
have hydrogen addition properties that can be monitored directly
using x-ray diffraction—a technique that provides clear insights
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into cluster structure and functionality.
Rare combinations
For the past 25 years, chemists have paired so-called ‘d-block
transition metals’, such as tungsten (W) and molybdenum (Mo),
with lightweight rare-earth metals, such as yttrium (Y), to increase
the storage capacity of hydride clusters. Because the nuclei of rare
earths are shielded by many electrons, these metals can pack high
numbers of hydrogen atoms into small crystal volumes without
suffering electronic repulsions. Unfortunately, once hydrogen gas
binds to a rare-earth metal, it tends to stay there. Mixing in d-block
metals alters the rare-earth reactivity so that on-demand hydrogen
storage and release can occur.
Until now, most of these combined metal hydrides were
constructed using mononuclear rare-earth building blocks, such as
YH, with a mononuclear d-block metal. Using a different strategy,
Hou and his colleagues recently devised innovative protocols to
isolate polynuclear rare-earth hydrides using large molecular
ligands to trap these typically unstable compounds in place2.
Polynuclear hydrides feature dense, interconnected networks of
‘bridging’ hydrogen atoms connected to two or more metals—
characteristics that led the researchers to explore their potential for
hydrogen storage applications.
“It is not difficult to imagine that hydrogen atoms could bond to
multiple metal atoms in a polynuclear polyhydride complex, and
the [mode of] bonding could be different with different metal
combinations,” says Hou. “However, it is not easy to prepare
quality polyhydride samples for high-precision structure
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determinations. Hydride complexes containing both rare-earth and
d-block transition metals are even more difficult to prepare because
of their air- and moisture-sensitivity.”
A Five-way First
Performing their experiments inside nitrogen-filled and humidityfree enclosures, the team mixed one of their carefully prepared
polynuclear complexes—four yttrium metals and eight hydrogen
atoms held together by bulky organic ligands—with either a Mo or
W pentahydride. After precipitating crystals out of the reaction,
they used x-ray and neutron diffraction experiments to view their
product’s atomic structure. These measurements showed that the
two metallic components fused together, yielding a Y4MH11 (M =
Mo, W) hydride with double-, triple-, and quadruple-bridged
hydrogen atoms.
Zapping the penta-metallic polyhydride with ultraviolet light
enabled the team to remove a protective phosphorus ligand and
increase the hydrogen bridging density within the cluster. This
produced the first hydride cluster where hydrogen is bonded to five
metals in a distinctive symmetry known as trigonal bipyramidal.
“The confirmation of a penta-coordinated hydrogen atom in this
geometry is unprecedented,” says Hou.
Step-by-step scrutiny
Hou and colleagues’ experiments then demonstrated that their
heterometallic clusters possessed critical hydrogen storage and
release capabilities. Heating H2 and Y4WH11 to 80 °C caused an
oxidative addition of the gas molecule to the cluster, which they
could reverse through ultraviolet-light treatment. Despite the
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Y4MoH11 molecule not responding to the same chemical tricks,
the researchers discovered that applying a vacuum could suck H2
from the cluster, giving a new Y4MoH9 complex. Exposing this
compound to hydrogen gas at room temperature spontaneously
regenerated the original molecule (Fig. 2).
According to Hou, the most striking aspect of this chemistry is that
the hydrogen addition to the Y4MoH9 cluster can be followed
from single crystal to single crystal—meaning that the starting
material, the reaction intermediates, and the product all retain the
same rigid morphology. “No metal hydrides have previously
shown such excellent crystallinity,” he notes.
After gingerly sealing a Y4MoH9 crystal into a thin, hydrogenfilled capillary tube, the researchers monitored the spontaneous
addition reaction over 60 hours. As the cluster gradually took in
hydrogen and changed color from black to red, they watched—at
precision greater than one-millionth of a meter—yttrium and
molybdenum atoms separate and shift within the crystal unit cell.
By providing the first-ever atom-resolved views of active sites and
bonding modes for hydrogen addition to an organometallic crystal,
these findings should aid design of more sophisticated alloys in the
future.
Theoretical calculations performed by the researchers indicated
that combining two metals with starkly different electronic
properties played a big role in giving the clusters their unique
reactivity. With wide swaths of the periodic table available for
exploring using this technique, breakthroughs in heterometallic
hydride materials may have only just begun.
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