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Файл:Английский язык для информационных технологий. Часть I. Учебное пособие по формированию иноязычной профессиональной компетенции студентов технических
.pdf
4. Hardware
5. Software
6. Program
7. Programming
8. Integrated circuit
9. Chip
10. Transistor
electronic circuits used inside all computers
d) a system which processes and stores great
amount of data solving problems of numerical
computation
e) a device which can carry out routine mental
tasks by performing simple operations at high
speed
f) an electronic and mechanical equipment in a
computer system
g) a set of programs, procedures and associated
documentation
h) the process of preparation a set of coded
instructions for a computer
i) a device that has input and output
represented in the form of physical quantities
j) a small piece of a semiconductor that greatly
reduced power consumption of a circuit
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MODULE 2
UNIT 1. WHAT IS OS? HOW CAN YOU
DEFINE ITS PLACE IN A COMPUTER SYSTEM?
I. READING
1.1. Read and translate the text “Can We Make Operating System
Reliable and Secure?”[24]
C
AN WE MAKE OPERATING SYSTEM RELIABLE AND SECURE
?
Micro kernels – long discarded as unacceptable because of their lower
performance compared with monolithic kernels – might be making a
comeback in operating systems due to their potentially higher reliability, which
many researchers now regard as more important than performance. The worst
offender when it comes to reliability and security is the operating system.
Although application programs contain many flaws, if the operating system
were bug free, bugs in application programs could do only limited damage. A
few words about the relationship between reliability and security are to be said.
Problems with each of these domains often have the same root cause: bugs in
the software. A buffer overrun error can cause a system crash (reliability
problem), but it can also allow a cleverly written virus or worm to take over the
computer (security problem). Although we focus primarily on reliability,
improving reliability can also improve security.
Current operating systems have two characteristics that make them
unreliable and insecure: They are huge and they have very poor fault isolation.
The Linux kernel has more than 2.5 million lines of code; the Windows XP
kernel is more than twice as large. The large size of current operating systems
means that no one person can understand the whole thing. Clearly, it is difficult
to engineer a system well when nobody really understands it. Operating
systems do not have isolation between components. A modern operating
system contains hundreds or thousands of procedures linked together as a
single binary program running in kernel mode. Every single one of the millions
of lines of kernel code can overwrite key data structures that an unrelated
component uses, crashing the system in ways difficult to detect. In addition, if
a virus or worm infects one kernel procedure, there is no way to keep it from
rapidly spreading to others and taking control of the entire machine.
Fortunately, the situation is not hopeless. Researchers are endeavoring
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to produce more reliable operating systems. There are four different
approaches that researchers are using to make future operating systems more
reliable and secure. The most conservative approach, Nooks, is designed to
improve the reliability of existing operating systems such as Windows and
Linux. Nooks maintains the monolithic kernel structure, with hundreds or
thousands of procedures linked together in a single address space in kernel
mode, but it focuses on making device drivers – the core of the problem – less
dangerous. In particular, Nooks protects the kernel from buggy device drivers
by wrapping each driver in a layer of protective software to form a lightweight
protection domain, a technique sometimes called sandboxing. The wrapper
around each driver carefully monitors all interactions between the driver and
the kernel.
The Nooks project’s goals are: to protect the kernel against driver
failures, to recover automatically when a driver fails, to do all of this with as few
changes as possible to existing drivers and the kernel. Protecting the kernel
against malicious drivers is not a goal. The idea is to run a special control
program, called a virtual machine monitor, on the bare hardware instead of an
operating system. The virtual machine creates multiple instances of the true
machine. Each instance can run any software the bare machine can. This
technique is commonly used to allow two or more operating systems, say Linux
and Windows, to run on the same hardware at the same time, with each one
thinking it has the entire machine to itself. The use of virtual machines has a
well-deserved reputation for good fault isolation – after all, if none of the virtual
machines even know about the other ones, problems in one machine cannot
spread to others. This research is to adapt this concept to protection within a
single operating system, rather than between different operating systems. This
approach directly attacks the core of the problem: having the entire operating
system run as a single gigantic binary program in kernel mode. Instead, only a
tiny microkernel runs in kernel mode with the rest of the operating system
running as a collection of fully isolated user-mode server and driver processes.
The microkernel handles interrupts, provides the basic mechanisms for
process management, implements inter process communication, and performs
process scheduling. The most radical approach comes from an unexpected
source – Microsoft Research. In effect, the Microsoft approach discards the
concept of an operating system as a single program running in kernel mode
plus some collection of user processes running in user mode, and replaces it
with a system written in new type- safe languages that do not have all the
pointer and other problems associated with C and C++.
Thus, each of the four different attempts to improve operating system
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reliability focuses on preventing buggy device drivers from crashing the
system. It is not yet known which, if any, of these approaches will be widely
adopted in the long run. Nevertheless, it is interesting to note that micro kernels
– long discarded as unacceptable because of their lower performance compared
with monolithic kernels – might be making a comeback due to their potentially
higher reliability, which many people now regard as more important than
performance.
Study the meaning of the following words and word combinations:
• a flaw
• sandboxing fault isolation
• entire
• to endeavor
• interrupt armored
• to discard to wrap
• type-safe language
1.2. Answer the following questions:
1. Are unreliability and insecurity the same from the OS point of
view?
2. How many approaches to the problem are discussed in the text?
3. What are their main ideas of the text?
4. What approach is more acceptable from your point of view?
Why?
1.3. Read and translate the text “Hardware, Software and
Firmware”[26]
H
ARDWARE, SOFTWARE AND FIRMWARE
The units that are visible in any computer are the physical components
of a data processing system, or hardware. Thus, the input, storage, processing,
and control devices are hardware. Not visible is the software — the set of
computer programs, procedures, and associated documentation that make
possible the effective operation of the computer system. Software programs are
of two types: systems software and applications software.
Systems software are the programs designed to control the operation of
a computer system. They do not solve specific problems. They are written to
assist people in the use of the computer system by performing tasks, such as
controlling all of the operations required, to move data into and out of a com-
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puter and all of the steps in executing an application program. The person who
prepares systems software is referred to as a systems programmer. Systems
programmers are highly trained specialists and important members of the
architectural team.
Applications software are the programs written to solve specific
problems (applications), such as payroll, inventory control, and investment
analysis. The word program usually refers to an application program, and the
word programmer is usually a person who prepares applications software.
Often programs, particularly systems software, are stored in an area of memory
not used for applications software. These protected programs are stored in an
area of memory called read only memory (ROM), which can be read from but
not written on.
Firmware is a term that is commonly used to describe certain
programs that are stored in ROM. Firmware often refers to a sequence of
instructions (software) that is substituted for hardware. For example, in an
instance where cost is more important than performance, the computer system
architect might decide not to use special electronic circuits (hardware) to
multiply two numbers, but instead write instructions (software) to cause the
machine to accomplish the same function by repeated use of circuits already
designed to perform addition.
Study the meaning of the following words and word combinations:
• hardware
• software
• system software
• application software
• firmware
• visible units
• procedure
• to associate
• associated documentation
• to execute applications programs
• payroll
• inventory control
• investment analyses
• to protect
• read-only memory (ROM)
• to refer to
• to substitute
• to cause
• to accomplish
• performance
1.4. Answer the following questions:
1. What is hardware?
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2. Give the definition of software.
3. What are the types of software?
4. What is the system software?
5. What kind of tasks does system software perform?
6. Who prepares systems software?
7. What is the application software?
8. What problems does application software solve?
9. What is firmware?
10. How can a computer system architect use firmware?
II. WRITING
2.1. Write the English equivalents of the given Russian words and
word combinations:
A) Видимые устройства; система обработки данных; аппаратное
обеспечение; набор компьютерных программ; соответствующая
документация; эффективная работа; системное программное обеспечение;
прикладное программное обеспечение; системный программист;
платежная ведомость; переучет; анализ инвестиций; прикладная
программа; работающий только в режиме чтения; постоянное
запоминающее устройство; последовательность команд; в случае;
производительность; электронная цепь; умножать числа; заставить
машину выполнять ту же функцию; выполнять сложение.
) Функциональный блок; цифровой компьютер; устройство
B
ввода; устройство управления; арифметико-логическое устройство;
центральный процессор; структура компьютерной системы; первичное
запоминающее устройство; вторичное ЗУ; рассмотрение; поэтому
последовательность; оперативное ЗУ; внутренняя память; промежуточные
результаты; подобие функции человеческого мозга; размешать
содержимое по требованию; система счисления; двоичная система
счисления; возможные величины; объем информации; двоичный код;
смежные ячейки памяти; последовательность символов;
быстродействующее устройство; полупроводник; доступный.
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2.2. Write the Russian equivalents of the given English words and
word combinations:
Storage: available storage; buffer storage; computer storage; data
storage; magnetic disk storage; magnetic tape storage; input storage; intermediate
storage; internal storage; laser storage; main storage; primary storage; secondary
storage; sequential-access storage; variable storage; virtual storage.
Value: absolute value; acceptable value; additional value; binary
value; byte value; character value; constant value; correct value; data value;
digit value; discrete values; invalid value; negative value; numerical value;
output value; valid value.
Digit: binary digit; binary-coded digit; check digit; information digit;
input digit; no significant digit; significant digit; digit-by-digit.
Sequence: out of sequence; alphabetic sequence; arithmetic
sequence; binary sequence; character sequence; code sequence; instruction
sequence; data sequence; digital sequence; historical sequence; increasing
sequence; program sequence; string sequence.
2.3. Translate the following sentences:
1. Это явление сейчас изучают.
2. Причины поломки еще не установлены.
3. Анализ показал, что операционная система является
ненадежной и незащищенной.
4. Я считаю, что гипотеза о возможном возвращении к
микроядрам в операционных системах вполне оправданна.
5. Эти формулы были выведены еще в прошлом веке.
6. Каковы критерии надежности операционнои системы?
7. Эти данные были получены до того, как их запросили.
8. Меморандум подписали неделю назад.
9. Это средство не может быть применимо в данной ситуации.
III. ПОВТОРЕНИЕ ГРАММАТИКИ
Страдательный залог (The Passive Voice)
Пассив – категория глагола, которая показывает, что объект или
предмет не сам производит деиствие, а действие производят над ним.
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Страдательный залог употребляется, когда исполнитель
действия очевиден или несуществен, или когда действие или его
результат более интересны, чем исполнитель.
Образуется страдательный залог аналитически с помощью
вспомогательного глагола TO BE в соответствующем времени, лице и
числе и причастия прошедшего времени смыслового глагола (to
be+Participle II).
Дополнение в активном залоге становится подлежащим в
пассивном залоге.
Подлежащее в активном залоге становится дополнением в
пассивном залоге и предваряется предлогом by (кем-то производится
действие) или предлогом with (чем-то производится действие). The
walls were covered with posters.
Subject Verb Object
ACTIVE My sister was driving the car.
PASSIVE The car was being driven by my sister.
Subject Verb Object
Предлог by опускается, если подлежащие в активном залоге –
people, one, someone/somebody и личные местоимения.
Somebody switched on the computer.
The computer was switched on.
Предлог by не опускается, если исполнитель действия
необходим для смысла предложения.
Linux was created by Linus Torvalds.
Когда мы хотим сказать, что кто-то или что-то совершил
действие, вопрос в пассивном залоге будет строиться следующим
образом:
Who/What ....... вy? Who was Linux created by?
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Когда в предложении два дополнения, то любое из них может
быть подлежащим в пассивном залоге.
Lou sent me the document in attachment./ I was sent the document
by Lou./ The document was sent to me by Lou.
Употребление пассивного залога соответствует правилам
употребления соответствующих времен в действительном залоге.
1. The Passive Simple Tenses
Обозначают простое регулярное действие над субъектом или
объектом.
To be + PII
The computer is rebooted every hour.
The computer was rebooted an hour ago.
The computer will be rebooted in an hour.
2. The Passive Continuous Tenses
Обозначают длительное действие над субъектом или объектом.
To be + being + PII + обстоятельство времени
The computer is being rebooted now.
The computer was being rebooted when I returned.
The Future Continuous Tense – не существует. Вместо формы
Future Continuous, которая отсутствует в страдательном залоге,
употребляется Future Indefinite Passive или Future Continuous Active.
Пример: Программу будут писать весь вечер. The program will
be written the whole evening. They will be writing a program the whole
evening.
3. The Passive Perfect Tenses
Обозначают законченное деиствие над объектом или субъектом.
Have + been + PII
The computer has already been rebooted.
The computer had been rebooted by the time I came.
The computer will have been rebooted by the time I come.
The Passive Perfect Continuous Tenses –
не существуют. Вместо
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данных форм употребляются соответствующие формы Passive Perfect
или Active Perfect Continuous.
Для образования вопросительной формы первый
вспомогательныи глагол ставится перед подлежащим.
Is the computer being rebooted now?
Для образования отрицательной формы отрицательная частица
not ставится после первого вспомогательного глагола.
The computer is not being rebooted now.
Общая таблица образование страдательного залога (Passive Voice)
Настоящее время
Simple Present am, is, are
+ Participle II Present Continuous am, is, are + being
Present Perfect have, has +being
Прошедшее время
Past Present was, were +
+ Participle II Past Continuous was, were +being
Past Perfect had + been + being
Будущее время
Simple Future shall, will be
Future Perfect Shall, will + have been
Infinitive
Инфинитив представляет собой неличную глагольную форму,
которая только называет действие, не указывая ни лица, ни числа.
Формальным признаком инфинитива является частица to, которая не
имеет самостоятельного значения и не принимает ударения. Однако
частица to перед инфинитивом часто опускается.
Инфинитив имеет формы действительного и страдательного
залога (to do, to be done), может быть перфектным и неперфектным (to
+ Participle II
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