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Автоматизированная информационная система (АИС) в экономике – это совокупность методов и средств информационного, технического, программно-математического и организационно-правового характера, предназначенная для информационного обеспечения решения экономических задач. В соответствии с кибернетическим подходом система управления представляет собой совокупность объекта управления, например предприятие, и субъекта управления - управленческого аппарата.

формирование основ информационной и компьютерной культуры, готовности эффективно использовать приобретенные в рамках изучения дисциплины теоретические знания, практические умения и устойчивые навыки применения современных информационных технологий в профессиональной деятельности. Цель курса: Задачи курса формирование представлений о возможностях современных информационных технологий; ознакомление с техническими характеристиками и составом программного обеспечения современных ПК; применение ПК для решения задач информационной поддержки и анализа предметной области средствами СУБД; использование инструментальных программных средств - текстовых и табличных процессоров - для работы с базами данных;

Введение Информатика – это наука, изучающая закономерности протекания информационных процессов в автоматизированных системах. Правовая информатика – это научное направление, изучающее закономерности протекания информационных процессов в автоматизированных системах в правовой сфере. посвящена проблемам формирования правовой информации, правовым аспектам использования информационных ресурсов, информационного взаимодействия, в том числе правовой защиты информации. Домашнее задание Выпишите основные информационные процессы и кратко их охарактеризуйте.

Вы скопировали полностью из Интернета текст нормативно-правового акта. Нарушили ли Вы при этом право владельца сайта, с которого скопировали текст? 1. Да 2. Нет 3. Нет, если у меня есть его разрешение. Можно ли разместить на своем сайте опубликованную в печати статью какого-нибудь автора? 1. Можно, с указанием имени автора и источника заимствования. 2. Можно, с разрешения издателя, издавшего данную статью. 3. Можно, но исключительно с ведома автора и с выплатой ему авторского вознаграждения. 4. Можно, поскольку опубликованные статьи не охраняются авторским правом

Существующие САПР технологических процессов «Спрут» - Московский государственный технический университет им. Н. Э. Баумана; «Вертикаль» - фирма АСКОН (Санкт-Петербург); «ТИС-процесс» - СПбГУ ИТМО каф. ТПС; «Т – FLEX» – ЗАО «Топ Системы» (Москва); «TECHCARD» - фирма ИНТЕРМЕХ (Белоруссия). Система «ВЕРТИКАЛЬ» Интерфейс ВЕРТИКАЛЬ

Корпорация Dassault Systems Дочерняя компания Dassault SmarTeam Corporation (Израиль) Создана в 1995 г. Офисы расположены в США, Израиле, Франции, Германии и Великобритании Более 230 сотрудников Более 40,000 пользователей в различных отраслях промышленности Продукт PDM - система ENOVIA SMARTEAM

процедурно - ориентированного программирования Особенности: процедурная декомпозиция на модули; нисходящее программирование; структуризация модулей (небольшой объем модулей, отступы, ликвидация оператора goto) Методология ГОСТ 19.701 -90 Основные понятия: класс, объект, отношения между классами Основные принципы ООП: наследование, Отношения между классами : инкапсуляция, полиморфизм Методология объектно – ориентированного программирования (ООП) зависимости, ассоциации, обобщения, агрегации

CAD – конструирование илделия; CAE – системы расчета элементов изделия; CAM – системы расчета управляющих программ; CAPP системы проектирования технологических процессов; PDM –системы (Product Date Management) система управления изделием. Примечание: Базовые системы PLM - решений Одновременно PDM-система является базовым средством, с помощью которого реализуется единое информационное пространство для всех этапов жизненного цикла изделия. Возможности PDM –системы : распараллеливание процессов проектирования объектов и процессов; синхронизация проведения изменений на основе приема RedLine; отслеживание жизненного цикла технологических документов; контроль процесса управления на основе технология «workflow»; быстрый авторизованный доступ к документам и моделям на основе электронного архива; работа над проектом удаленных пользователей через Интернет.

Жизненный цикл изделия ТПП ТхПП Компьютерная поддержка этапов ЖЦИ получила свое оформление в методологии и стандартах ИПИ ИПИ - Информационная Поддержка процессов жизненного цикла Изделия). ИПИ - русскоязычный аналог известного c середины 80-х годов прошлого столетия термина CALS CALS - Computer-Aided Acquisition and Lifecycle Support – поддержка непрерывных поставок и жизненного цикла. Составляющие развиваются на протяжении ЖЦИ определение продукта полное электронное описание изделия среда и ресурсы его создания, среда эксплуатации)

Спиральная модель проектирования Компания Rational Software Corporation Методология КИС на базе унифицированного процесса – Rational Unified Process - RUP использование языка UML; большой набор справочных пособий и шаблонов; наличие инструментария (Rational Suite) для эффективного проектирования сложных программных систем.

Требование системности при разработке КИС Система - совокупность взаимосвязанных элементов, образующих целостность объекта Основные термины системного подхода: Структура - организация взаимодействия элементов системы посредством определённых связей  Функция - назначение элемента в системе Состояние - стабильных значений переменных параметров объекта Процесс - динамическое изменение системы во времени. Требование комплексности при разработке КИС Комплексный подход – это требование учёта входящих в структуру КИС взаимосвязанные факторы, которые влияют на разрабатываемую КИС Комплексный подход имеет два аспекта: а) применительно к КИС б) применительно к инструментарию, с помощью которого разрабатывается и эксплуатируется КИС .

Информационная система Входной поток X={x(i)} Выходной поток Y={y(i)} Правила (алгоритмы) F поведения системы X → Y Виды обеспечения методическое (комплекс эксплуатационных документов, а так же технический и рабочий проект ИС); математическое (методы и алгоритмы для ИС); программное (комплекс программ для ИС); информационное (информационная база и базы данных) техническое (компьютеры, сетевые средства и серверы); организационно-правовое (комплекс документов, регламентирующих организацию ИС, функции подразделений, права доступа и меру ответственности отдельных лиц).

Информационная система — прикладная программная система, ориентированная на сбор, хранение, поиск и обработку информации. Классификация информационных систем Основания классификации: область применения; уровень функциональности; масштаб использования; Способ организации работ.

Mathematical Backgrounds. Information Theory In 1949, Shannon provides a theoretical foundations for cryptography based on his fundamental work on information theory. He measured the theoretical secrecy of a cipher by the uncertainty about the plaintext given the received ciphertext. If, no matter how much ciphertext is intercepted, nothing can be learned about the plaintext, the cipher achieves perfect secrecy. Entropy and Equivocation Information theory measures the amount of information in a message by the average number of bits needed to encoded all possible messages in an optimal encoding. The Sex field in a database, for example, contains only one bit of information because it can be encoded with one bit (Male can be represented by “0”, Female by “1”). If the field is represented by an ASCII character encoding of the character strings “MALE” and “FEMALE”, it will take up more space, but will not contain any more information. Mathematical Backgrounds. Information Theory The amount of information in a message is formally measured by the entropy of the message. The entropy is a function of the probability distribution over the set of all possible messages. Let X1,..., Xn be n possible messages occurring with probabilities p(X1),...,p(Xn), the sum of this probabilities p(Xi), i=1,...,n equals to one. The entropy of a given message is defined by the weighted average: H(X)=−Σinp(Xi)log2 p(Xi). As the sum taken over all messages X: H(X)=–ΣXp(X)log2 p(X)=ΣXp(X)log2 [1/p(X)].

Some ciphers actually used by Soviet spies used a square like this: Encryption Algorithms The Straddling Checkerboard Eight of the most common letters are translated to a single digit. The two digits not used in this way begin two-digit combinations that stand for the remaining letters. This is an example of a variable length code with the prefix property. When it is possible to tell, from the digits one has already seen of a symbol, whether or not one needs to include the next digit in the symbol, then spaces between the digits of a symbol are not needed, and this is what is known as the prefix property. Of course, the second digit of a two-digit combination could also have stood, by itself, for another letter; but because when you start from the beginning and move forwards, there is no chance of confusion, this is a workable and usable system. Thus, the message SENDMONEY would become 4 1 0 22 25 7 0 1 66, or, rather, 41022 25701 66 because spaces to show where the letters begin are not needed; the first digit representing a letter determines if its substitute is one or two digits long. More complicated codes that work this way, using only the two binary digits 0 and 1, are used as a form of data compression. The most famous variable-length prefix-property binary codes are the Huffman codes; Encryption Algorithms The Straddling Checkerboard

Encryption Algorithms Transposition Cipher A lot of codes are simple in design. Just by changing the order of words, letters, or the way read them can turn the message into secret code. The simplest examples of the Transposition Ciphers are: Lumping Words (Format) Get rid of spaces and returns to lump words together. Use upper case to make the code harder to read and decode. Ciphertext: THISISHARDCODEFORMANYPEOPLE Message: THIS IS HARD CODE FOR MANY PEOPLE Character Bloks Block letter of a message by 2,3 or more characters. Ciphertext: TH IS IS HA RD CO DE FO RM AN YP EO PL E Message: THIS IS HARD CODE FOR MANY PEOPLE Backwards English Writing words, sentences, or entire message backwards can be very confusing! Ciphertext: SIHT SI DRAH EDOC ROF YNAM ELPOEP Message: THIS IS HARD CODE FOR MANY PEOPLE Reading SIHT backwards yields the answer THIS. Encryption Algorithms Transposition Cipher Transposition cipher rearrange characters according to some scheme. This rearrangement was classically done with the aid of some type of geometric figure. Enciphering procedure consists of two steps as shown next: Plaintext Figure Ciphertext Write-in Take-off First, the plaintext was written into the figure according to some “Write-in” path, then the ciphertext was taken off the figure according to some “Take-off” path. Example 2.1. Suppose that the plaintext CRYPTOGRAPHY is written into 3 rows by 4 columns matrix by rows as follows: 1 2 3 4 C R Y P T O G R A P H Y If the columns are taken off in the order 3-1-4-2, the resulting ciphertext is YGHCTAPRYROP.

Contents Introduction: Data security. Fundamental concepts of cryptography. Transposition and Substitution ciphers: Simple transposition. Product cipher. Simple substitution cipher. Caesar cipher. Vigener cipher. Mono and Poly alphabetic substitution cipher: Playfair cipher. Rotor machines. The Enigma: a unique rotor machine. Data Encryption Standard (DES): History of the DES. DES algorithms.Weak and semi weak keys. Advanced DES versions. IDEA. Blowfish. Advanced Encryption Standard (AES): Reindgiil Algorithm. Number theory: Prime numbers. Euler’s function. Euler’s theorem. Congruence. Public Key Cipher: Principles of the public key cipher. One-way function. Deffie and Hellman algorithm. Contents cont. RSA Cipher: Riverst, Shamir and Adleman public key cipher. Practical aspects. Linear Feedback Shift Register: Pseudorandom key generation by LFSR. M- sequences. Stream cipher: Synchronous stream ciphers. Self- synchronizing cipher. Cryptographic Keys Management: Keys generation, distribution and athetifacation of Public Keys Communication Security: Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL). Authentication Protocols: Password- authentication key agreement protocols. Password Authentification Protocol (PAP)

Science, which learns, as it is necessary to arrive to save the maintenance of messages in secret, is named as cryptography. The people who are engaged in cryptography, call cryptographer. Cryptanalysts are experts in the field of cryptanalysis - sciences about opening of cods, which answers a question on how to read the clear text disappearing under the coded. The section of a science uniting cryptography and cryptanalysis, is named by cryptology. The cryptography is engaged in search and research of mathematical methods of information conversion. Sphere of interests of cryptoanalysis - research of the information possibility decoding without knowledge of keys. The modern cryptography includes four large sections: 1) Symmetric cryptosystems. 2) Cryptosystems with opened key. 3) Digital signature systems. 4) Control of keys. The main directions of usage of cryptography methods - transmission of the confidential information on data links (for example, e-mail), authenticity installation of the transferred messages, the storage of information (documents, databases) on carriers in coded type.

The process of making an archive file is called archiving or packing. Reconstructing the original files from the archive is termed unarchiving, unpacking or extracting. An archive file is a file that is composed of one or more files along with metadata that can include source volume and medium information, file directory structure, error detection and recovery information, file comments, and usually employs some form of lossless compression. Archive files may also be encrypted in part or as a whole. Archive files are used to collect multiple data files together into a single file for easier portability and storage. Computer archive files are created by File archiver software, Optical disc authoring software, or Disk image software that uses an archive format determined by that software. The file extension or file header of the archive file are indicators of the file format used. Archive files are sometimes accompanied by separate parity archive (PAR) files that allow for additional error detection and recovery, particularly in recovery of missing package files in a multi-file archive. Archives can have extensions like .zip, .rar, .tar and etc. Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data. The term lossless is in contrast to lossy data compression, which only allows an approximation of the original data to be reconstructed, in exchange for better compression rates. Lossless data compression is used in many applications. For example, it is used in the popular ZIP file format and in the Unix tool gzip. It is also often used as a component within lossy data compression technologies.

1.7.1. BIOS BIOS stands for Basic Input and Output System. It is sometimes called ROM BIOS because it is stored in a Read-Only Memory (ROM) chip on the mainboard. BIOS is the first program to run when you turn on your computer. BIOS performs the following functions: 1. Initializing and testing hardware in your computer (a process called “POST”, for Power On Self Test). 2. Loading and running your operating system. 3. Helping your operating system and application programs to manage your PC hardware by means of a set of routines called BIOS Run-Time Service. 1.7.1.1. BIOS SETUP BIOS Setup is an interactive BIOS program that you need to run when: 1. Changing the hardware of your system. (for example: installing a new Hard Disk etc..) 2. Modifying the behavior of your computer. (for example: changing the system time or date, or turning special features on or off etc.) 3. Enhancing your computer’s behavior. (for example: speeding up performance by turning on shadowing or cache) How to run BIOS Setup: • To access BIOS setup menu, press key after “POST”, and before the OS is loaded. The BIOS usually display the following message: Press DEL to enter SETUP

Fig. 1.6.1. M.Flynn's classifications: classes SISD and SIMD CPU is one or several processor elements, CU is a control unit, Mem is the data memory. Classical serial cars concern class SISD or, otherwise, cars a fon-nejman type, first of all. In such cars there is only one stream of the commands, all commands are processed consistently one after another and each command initiates one scalar operation. SIMD (Single Instruction stream/Multiple Data stream) - a single stream of commands and a plural data stream (fig. 1.6.1). In this class of architecture one stream of commands including, unlike the previous class, vector commands remains. It allows carrying out one arithmetic operation at once over many data, for example, over vector elements. MISD (Multiple Instruction stream/Single Data stream) - a plural stream of commands and a single data stream (fig. 1.6.2). Definition means presence in architecture of many processors processing the same data stream. However neither Flynn, nor other experts in the field of architecture of computers could not present till now a convincing example of the real-life computing system constructed on the given principle. A number of researchers is carried by conveyor cars to the given class, however it has not found a definitive recognition in scientific community. We will consider that while the given class is empty.

use without knowledge of system of commands is absolutely impossible, after all the Assembler language represents symbolical record of digital codes of computer language, codes of commands of the processor. Certainly, for development of the software there are every possible software. To use them it is usually possible and without knowledge of system of commands of the processor. More often programming languages of high level, such as Pascal and SI are applied. However the knowledge of system of commands and the Assembler language allows to increase several times efficiency of some most important parts of the software of any micropro-cessor system - from the microcontroller to the personal computer. For this reason in this chapter we will consider the main types of commands which are available for the majority of processors, and features of their application. Each command, chosen (read) of memory the processor, defines algorithm of behavior of the processor on the next some steps. The code of command speaks about what operation should be executed to the processor and with what operands (that is codes of data) where to take initial information for command execution and where to place result (if it is necessary). The code of command can borrow from one to several bytes, and the processor learns about that, how many command byte he should read, from the first byte read by it or a word. In the processor the code of command is deciphered and will be transformed to a set of the micro operations which are carried out by separate knots of the processor. But to the developer of microprocessor systems this knowledge isn't too important, to it the result of performance of this or that command is important only. 2.3.1. Addressing of operands The most part of commands of the processor works with codes of data (operands). One commands demand entrance operands (one or two), others give out target operands (one operand is more often). Entrance operands are called still as operands sources, and days off are called as operands receivers. All these codes of operands (entrance and target) should settle down somewhere. They can be in internal registers of the processor (the most convenient and fast option). They can settle down in system memory (the most widespread option). At last, they can be in input-output devices (the most exceptional case).

In item calculation systems any number is represented in the form of sequence of figures and signs which quantitative value depends on what place (position) is borrowed with everyone from them among. Quantity of the various figures used for the image of numbers in an item calculation system, name its basis. I.e. if in a calculation system for the image of numbers it is used r various among themselves the figures designating integers the basis of this system will be number r, being by the whole positive number. Let's consider the sequence of figures representing some number in which the whole and fractional parts are divided by a comma: ± an-1 an-2 ... aj ... a1a0 If in the set number to renumber the positions borrowed in figures, an index i we shall see, that it runs the sequence of values laying within the limits of -m = = 0. For an estimation of quantitative value of each category of number the basis of a calculation system which specifies is used, in how many times unit i+1 the category is more than unit i the younger category. Considering above told, set number it is possible to present so: ± (an-1*rn-1+an-2*rn-2+ ... +a0*r0) The given expression is used for record of numbers in any item calculation system.

In 1945 father of modern computer architecture John von Neumann, a large mathematician prepared a lecture about a machine which would keep the programs in memory. A lecture was sent to the scientists and got a mass appeal, as in him von Neumann clear and simply formulated general principles of functioning of universal computing devices, or computers. He was the consultant of project EDVAC and brought in the large personal payment in many fundamental inventions which underlay one of the first in history computers. In 1946 engineers which headed development, John Eckert and John Мauchly made attempt patent all bases of EDVAC technology, including those things which was thought by von Neumann. The first computer, in which principles von Neumann were incarnate, was built in 1949 by English researcher Maurice Wilkes. And for today swingeing majority of computers is done in accordance with principles of von Neumann (Fig. 1). CPU is a central processor unit. ALU is arithmetic and logic unit - for arithmetic calculations and acceptance of logical decisions. Memory is storages of data - serves for storage of information. CU is control unit - co-ordination of different blocks of COMPUTER.