Special Purpose Application Software.

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Special Purpose Application Software is the software created for execution of a single specific task. Some examples are Chess game, calculator, camera application in your mobile phone which allows you only to capture and share pictures, web browsers, media players, calendar programs.

Evolution of operating systems. Classification of operating systems, including for mobile devices.

What is Windows 7?It is redesigned with Windows Shell with a new taskbar. Windows 7 includes a number of new features, such as advances in touch and handwriting recognition, support for virtual hard disks, improved performance on multi-core processors, improved boot performance, Direct Access, and kernel improvements.

System requirements

Windows 7 requires the following computer hardware:

32 Bit		64 Bit
A Processor of 1 GHz or faster 32-bit	A Processor of 1 GHz or faster 64-bit
(x86)		(x64)
At least 1 GB of RAM memory	At least 2 GB of RAM memory
A hard disk with at least 16GB space	A hard disk with at least 20GB space
Available		available.
DirectX® 9 graphics processor with		DirectX® 9 graphics processor with
WDDM or higher driver		WDDM or higher driver
A DVD drive from which to install		A DVD drive from which to install
Windows.		Windows.
A monitor, keyboard, and mouse or		A monitor, keyboard, and mouse or
other pointing device.		other pointing device.

Table 2- Windows 7 Requirements

Basic Operations in Windows7.Let us have a look at the basic operations available with Windows 7. This knowledge will be helpful to you to make working with your computer easy.

First, we will learn about some required fundamental skills before performing basic operations available with your operating systems.

Log on to your computer.The process of starting a computer session is called logging on. When you start the computer, Windows displays a Welcome screen containing links to each of the computer's active user accounts. (If your computer is part of a domain, you will need to press Ctrl + Alt + Delete to display the Welcome screen.) You select your user account and, if your account is password protected, enter your password to log on to the computer. See Table 3 below for the login interface. When logging on to a computer which is part of a domain, you will always enter your domain credentials.

Brief descriptions of each component are given below.

N	Name	Brief Description

	Desktop	Work area on which you see your programs
	Start Menu	Let you open programs available in your computer
	Task Bar	Let you launch and monitor running programs
	Notification area	A portion of the taskbar that provides a temporary source for
		notifications and status.
	Task Buttons	Currently opened programs/applications
	Desktop Icons	Icons that belongs to and leads you to important parts of the
		computer
	Shortcut Icons	Easy way to access programs
	Windows Gadgets	Popular mini-programs
	Table 3: Components of Windows 7 User Interface

Questions:

1. What is Software?

2. Differentiate System software and Application software.

3. What are the responsibilities of Operating Systems?

4. Define the following with suitable examples.

Single–user OS

Multi-user OS

5. What are utility programs? Define some tasks performed by them.

6. What is meant by library programs?

7. What are program language translators? Briefly describe three translating approaches.

8. State the advantages and disadvantages of Bespoke Application Software.

References

2. Lorenzo Cantoni (University of Lugano, Switzerland) James A. Danowski (University of Illinois at Chicago, IL, USA) Communication and Technology, 576 pages.

3. Craig Van Slyke Information Communication Technologies: Concepts, Methodologies, Tools, and Applications (6 Volumes). ISBN13: 9781599049496, 2008, Pages: 4288

4. Utelbaeva A.K.,Utelbaeva A.K. Study guide for lectures on discipline “Computer science”, Shimkent 2008, 84 pages.

Lecture №4. Human-computer interaction.

Purpose: to work with a system, the users need to be able to control the system and assess the state of the system.

Plan:

1. User interface as means of human-computer interaction. Usability of interfaces.

2. Types of interfaces: command line interface, text interface, graphic interface.

3. Physical and mental characteristics of the user. Development stages of the user interface. Types of testing of interfaces (testing of users). Perspectives of development of interfaces.

1.User interface as means of human-computer interaction. Usability of interfaces.

Human–computer interaction (commonly referred to as HCI) researches the design and use of computer technology, focused on the interfaces between people (users) and computers. Researchers in the field of HCI both observe the ways in which humans interact with computers and design technologies that let humans interact with computers in novel ways.

Humans interact with computers in many ways; and the interface between humans and the computers they use is crucial to facilitating this interaction. Desktop applications, internet browsers, handheld computers, and computer kiosks make use of the prevalent graphical user interfaces (GUI) of today. Voice user interfaces (VUI) are used for speech recognition and synthesing systems, and the emerging multi-modal and gestalt User Interfaces (GUI) allow humans to engage with embodied character agents in a way that cannot be achieved with other interface paradigms. The growth in human-computer interaction field has been in quality of interaction, and in different branching in its history. Instead of designing regular interfaces, the different research branches have had different focus on the concepts of multimodality rather than unimodality, intelligent adaptive interfaces rather than command/action based ones, and finally active rather than passive interfaces

The Association for Computing Machinery (ACM) defines human-computer interaction as "a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them". An important facet of HCI is the securing of user satisfaction (or simply End User Computing Satisfaction). "Because human–computer interaction studies a human and a machine in communication, it draws from supporting knowledge on both the machine and the human side. On the machine side, techniques in computer graphics, operating systems, programming languages, and development environments are relevant. On the human side, communication theory, graphic and industrial design disciplines, linguistics, social sciences, cognitive psychology, social psychology, and human factors such as computer user satisfaction are relevant. And, of course, engineering and design methods are relevant."Due to the multidisciplinary nature of HCI, people with different backgrounds contribute to its success. HCI is also sometimes termed human–machine interaction (HMI), man–machine interaction (MMI) or computer–human interaction (CHI).

Poorly designed human-machine interfaces can lead to many unexpected problems. A classic example of this is the Three Mile Island accident, a nuclear meltdown accident, where investigations concluded that the design of the human–machine interface was at least partly responsible for the disaster. Similarly, accidents in aviation have resulted from manufacturers' decisions to use non-standard flight instrument or throttle quadrant layouts: even though the new designs were proposed to be superior in basic human–machine interaction, pilots had already ingrained the "standard" layout and thus the conceptually good idea actually had undesirable results.

Human–computer interaction studies the ways in which humans make, or don't make, use of computational artifacts, systems and infrastructures. In doing so, much of the research in the field seeks to improve human-computer interaction by improving the usability of computer interfaces. How usability is to be precisely understood, how it relates to other social and cultural values and when it is, and when it may not be a desirable property of computer interfaces is increasingly debated.

The human–computer interface can be described as the point of communication between the human user and the computer. The flow of information between the human and computer is defined as the loop of interaction. The loop of interaction has several aspects to it, including:

· Visual Based :The visual based human computer inter-action is probably the most widespread area in HCI research.

· Audio Based : The audio based interaction between a computer and a human is another important area of in HCI systems. This area deals with information acquired by different audio signals.

· Task environment: The conditions and goals set upon the user.

· Machine environment: The environment that the computer is connected to, e.g. a laptop in a college student's dorm room.

· Areas of the interface: Non-overlapping areas involve processes of the human and computer not pertaining to their interaction. Meanwhile, the overlapping areas only concern themselves with the processes pertaining to their interaction.

· Input flow: The flow of information that begins in the task environment, when the user has some task that requires using their computer.

· Output: The flow of information that originates in the machine environment.

· Feedback: Loops through the interface that evaluate, moderate, and confirm processes as they pass from the human through the interface to the computer and back.

· Fit: This is the match between the computer design, the user and the task to optimize the human resources needed to accomplish the task.

Topics in HCI include:

Definition of User Interface.

In computer science and human-computer interaction, the user interface (of a computer program) refers to the graphical, textual and auditory information the program presents to the user. The user employs several control sequences (such as keystrokes with the computer keyboard, movements of the computer mouse, or selections with the touchscreen) to control the program.

2. Types of interfaces: command line interface, text interface, graphic interface.

There exist several types of user interfaces.

· Command-Line Interface (CLI): The user provides the input by typing a command string with the computer keyboard and the system provides output by printing text on the computer monitor.

A Command Line Interface allows the user to interact directly with the computer system by typing in commands (instructions) into a screen,

You cannot just type in any kind of instruction of course, because the computer will only react to a definite set of words.

These commands are very specific, for example in DOS you could type in:

copy c:\item.txt d:\

That tells the machine to copy the file 'item.txt' that resides in the root directory of drive C: into the root directory of drive D:\

Many commands have what are called 'switches'. These are extra parameters or flags which add extra functionality to the command. For example:

»Dir gives a directory listing

»Dir /w gives the listing across the page

»Dir /s includes the sub directories

»Dir /p pauses at the bottom of every page

Before Windows was developed, this type of user interface was what most people used to get the computer to follow instructions. Nowadays, very few people have the knowledge to be able to use a command line interface.

An example of this type of interface is DOS (Disk Operating System).

Sometimes referred to as the command screen or a text interface, the command line or Windows command line is a user interface that is navigated by typing commands at prompts, instead of using the mouse. For example, the Windows folder in a Windows command line (MS-DOS) is C:\Windows> (as shown in the picture) and in Unix or Linux, it may be % or >. Unlike a GUI operating system, a command line only uses a keyboard to navigate by entering commands and does not utilize a mouse for navigating.

Because a command line interface requires unique commands, this interface is often more difficult to learn because of the need to memorize dozens of different commands. However, a command line operating system can be a very valuable resource and should not be ignored. For example, users who have Microsoft Windows may find trivial tasks, such as renaming 100+ files in a folder, a very difficult task. However, renaming 100+ files in a directory can be done in less than a minute with a command entered into the command line.

Advantages and Disadvantages
Advantages	Disadvantages
If the user knows the correct commands then this type of interface can be much faster than any other type of interface	For someone who has never used a CLI, it can be very confusing
This type of interface needs much less memory (RAM) in order to use compared to other types of user interfaces	Commands have to be typed precisely. If there is a spelling error the command will fail
This type of interface does not use as much CPU processing time as others	If you mis-type an instruction, it is often necessary to start from scratch again
A low resolution, cheaper monitor can be used with this type of interface	There are a large number of commands which need to be learned - in the case of Unix it can be hundreds
A CLI does not require Windows to run	You can't just guess what the instruction might be and you can't just 'have a go'.

Table 4- Advantages and Disadvantages

WIMP or GUI Interface

A graphical user interface (GUI) is the most common type of user interface in use today. It is a very 'friendly' way for people to interact with the computer because it makes use of pictures, graphics and icons - hence why it is called 'graphical'.

A GUI (pronounced gooey) is also known as a WIMP interface because it makes use of:

Windows - a rectangular area on the screen where the commonly used applications run

Icons - a picture or symbol which is used to represent a software application or hardware device

Menus - a list of options from which the user can choose what they require

Pointers - a symbol such as an arrow which moves around the screen as you move your mouse. Helps you to select objects.

Advantages and Disadvantages
Advantages	Disadvantages
This type of user interface is easy to use, especially for a beginner	GUIs take up a much larger amount of hard disk space than other interfaces
It is easy to explore and find your way around the system using a WIMP/ GUI interface	They need significantly more memory (RAM) to run than other interface types
You do not have to learn complicated commands	They use more processing power than other types of interface
There are usually a reasonable 'help' system included with WIMP interfaces	They can be slow for experienced programmers to use. These people often find CLI interfaces much faster to use
You get the benefits of WYSIWYG
They let you exchange data between different software applications

Table 5- Advantages and Disadvantages

A GUI is an interface built around visual (graphical) things:

· Windows are regions of the screen used to display information

· Icons are small pictures that are used to represent folders, software, etc.

· Menus are lists of options the user can select from

· A pointer is an arrow that can be moved around the screen and is used to select things

Windows XP is an example of an operating system with a GUI.

GUIs are quite easy to use due to the visual nature of the interface – the user has lots of visual clues as to what things do.

However, to display all of the nice graphics required by a GUI takes a lot of computing power so quite a powerful computer is needed.

· Graphical User Interface (GUI): The use of pictures rather than just words to represent the input and output of a program. Input is accepted via devices such as keyboard and mouse.

Many years ago when computers were not very powerful they could not display the colourful graphics required for a GUI. The only interface available to most computer uses was the ‘command line’.

The user would see nothing but a black screen. They would have totype a command to make anything happen.

To copy a text file called NOTES from a floppy disc to the hard drive the user would have to type:> COPY A:\NOTES.TXT C:\

The user would have to learn a whole set of strange commands so that they could make use of the computer system. Plus it was not very interesting look at – no visual clues to tell you what to do next.

3. Physical and mental characteristics of the user. Development stages of the user interface. Types of testing of interfaces (testing of users). Perspectives of development of interfaces.This meant computers used to be quite difficult to use, so this type of interface is only really suitable for expert users.

The system that people use to interact with a computer (to give it commands, to see the results of those commands, etc.) is known as the user interface.

Operating system command-line interfaces

Operating system (OS) command line interfaces are usually distinct programs supplied with the operating system.

A program that implements such a text interface is often called a command-line interpreter, command processor or shell.

Application command-line interfaces

Application programs (as opposed to operating systems) may also have command line interfaces.

An application program may support none, any, or all of these three major types of command line interface mechanisms:

1. Parameters: Most operating systems support a means to pass additional information to a program when it is launched. When a program is launched from an OS command line shell, additional text provided along with the program name is passed to the launched program.

2. Interactive command line sessions: After launch, a program may provide an operator with an independent means to enter commands in the form of text.

3. OS inter-process communication: Most operating systems support means of inter-process communication (for example; standard streams or named pipes). Command lines from client processes may be redirected to a CLI program by one of these methods.

Menu Interface

This type of interface lets you interact with a computer or device by working your way through a series of screens or menus.

Think about your iPod or mobile phone, they both use a menu driven interface. You are presented with a menu, you make a choice and then the next menu appears on the screen. You make another choice and so on.

Cashpoint machines (ATMs) are another good example of a menu driven interface.

Menu driven interfaces can also be verbal rather than visual. Have you ever made a telephone call and been asked to 'press 1 for abc, press 2 for def, press 3 for ghi'?

Most of the software that you use have menu interfaces. You can use many features of the software by working your way through the menu options. Have a look at the menus in your word processor or spreadsheet package and see how many different choices you are given.

A well designed menu interface is simple to use, you just follow the instructions and make your choices.

Advantages and Disadvantages
Advantages	Disadvantages
Extremely easy to use. Someone who has never seen the interface before can work out what to do	A poorly designed menu interface may be slow to use
There are no commands to learn or remember	It can be irritating if there are too many menu screens to work through - users get annoyed or bored if it takes too long
Step-by-step options are given so that the user doesn't have to remember anything	You often can't go to the exact place you want right at the start. You have to work your way through the menu screens even if you know where you want to get to.
Even if you don't know what to do, you can usually guess your way around the options	The menu can take up a large part of the screen so you have to keep flicking back and forwards between applications
Menu interfaces don't have to be visual, they can be spoken - good for telephones or for visually impaired people	If the menu is poorly designed it might be hard to read e.g. writing is too small for people with poor sight, colours might clash and be difficult to read, font style might be hard to read.

Table 6- Advantages and Disadvantages

Lecture №5. Database systems.

Purpose: to provide an overview about Database Management Systems (DBMS) and introduce one of DBMS: SQL

Plan:

1.Bases of database systems: concept, characteristic, architecture. Data models. Normalization. Integrity constraint on data. Query tuning and their processing.

2.Fundamentals of SQL. Parallel processing of data and their restoration.

3.Design and development of databases. Technology of programming of ORM. The distributed, parallel and heterogeneous databases.

1.Bases of database systems: concept, characteristic, architecture. Data models. Normalization. Integrity constraint on data. Query tuning and their processing.

Introduction to Databases.A database is a structured collection of records or data. A computer database is a kind of software to organize the storage of data. Databases help you organize this related information in a logical fashion for easy access and retrieval. To develop a database, there are several models used such as Hierarchical model, Network model, Relational model, Object-Oriented model etc.

Hierarchical model.In a hierarchical model, data is organized into an inverted tree-like structure. This structure arranges the various data elements in a hierarchy and helps to establish logical relationships among data elements of multiple files. Each unit in the model is a record which is also known as a node. Each record has a single parent.

Figure 1- Hierarchical Model

Network model.The network model tends to store records with links to other records. Each record in the database can have multiple parents, i.e., the relationships among data elements can have a many to many relationships. So this model is an expansion to the hierarchical structure, allowing many-to-many relationships in a tree-like structure that allows multiple parents.

The network model provides greater advantage than the hierarchical model in that it promotes greater flexibility and data accessibility.

Figure 2- Network Model

Relational model.The relational model for the database management is a database model based on relations. The basic data structure of the relational model is a table where information about a particular entity (say, a student) is represented in columns and rows. The columns enumerate the various attributes(i.e. characteristics) of anentity(e.g. student name, address, registration _number).The rows (also called records) represent instances of an entity (e.g. specific student).

Object –Oriented model.In this Model we have to discuss the functionality of the object oriented Programming. It takes more than storage of programming language objects. It provides full-featured database programming capability, while containing native language compatibility. It adds the database functionality to object programming languages. This approach is the analogical of the application and database development into a constant data model and language environment. Applications require less code, use more natural data modeling, and code bases are easier to maintain. Object developers can write complete database applications with a decent amount of additional effort. But object-oriented databases are more expensive to develop.

Database Management System.A Database Management System (DBMS) is computer software designed for the purpose of managing databases based on a variety of data models. A DBMS is a complex set of software programs that controls the organization, storage, management, and retrieval of data in a database. DBMS are categorized according to their data structures or types, sometime DBMS is also known as a Database Manager. Data management tasks fall into one of four general categories as given below:

Entering data into the database.

Housekeeping tasks such as updating data, deleting obsolete records, and backing up the database.

Sorting the data: arranging or re-arranging the database‟s records.

Obtaining subsets of data.

There are several advantages in DBMS such as reduced data redundancy and inconsistency, enhanced data integrity, improved security etc.

Normalization of databases is a process of transformation of database to the kind answering the normalized forms.

Classification of limitations of integrity

In the theory of relational databases it is accepted to distinguish four types of limitations of integrity:

· Limitation of database is name a limit on values that it is let to accept to the indicated database.

· Limiting to the variable of relation is name a limit on values that it is let to accept to the indicated variable of relation.

· Limitation of attribute is name a limit on values that it is let to accept to the indicated attribute.

· Limitation of type is not that another, as determination of great number of values this type consists of that.

Example of widespread restriction of level of a variable of the relation is the potential key; an example of widespread restriction of level of the database is the foreign key.

Integrity and truth of data in a DB

Integrity of a DB doesn't guarantee reliability (truth) of the information which is contained in it, but provides at least plausibility of this information, rejecting certainly improbable, impossible values. Thus, it isn't necessary to confuse integrity (consistency) of a DB to truth of a DB. Truth and consistency — not same.

Reliability (or truth) is compliance of the facts which are stored in the database, to the real world. It is obvious that determination of reliability of a DB requires possession of full knowledges both about DB contents, and about the real world. Determination of integrity of a DB requires only possession of knowledge of contents of a DB and about the rules set for it. Therefore the DBMS can't guarantee existence in the database only of the true expressions; all that she can make, are to guarantee absence of any data causing violation of integrity constraints (that is to guarantee that she doesn't contain any data not compatible to these restrictions).

Query tuning

The DBMS SQL component which defines how to realize navigation on physical data structures for access to the required data, is called the query optimizer (query optimizer).

The navigation logic (algorithm option) for access to the required data is called way or the access method (access path).

The sequence of the operations performed by the optimizer which provide the selected access paths is called the execution plan (execution plan).

Process, the used query optimizer for determination of an access path, is called query tuning (query optimization).

During process of optimization of requestsways of access for all types of the SQL DML teams are determined. However the SQL SELECT team represents the greatest complexity in the solution of a task of the choice of a way of access. Therefore this process is usually called optimization of a request, but not optimization of ways of access to data. Further, it should be noted that the term "optimization of requests" is not absolutely exact — in the sense that there is no guarantee that in the course of optimization of a request the optimum way of access will be really received.

Thus, optimization of requests can be determined as the amount of all techniques which are applied to increase in efficiency of handling of requests.

2.Fundamentals of SQL. Parallel processing of data and their restoration.

The structured language of requests (Structured Query Language) – the standard of communication with the database which is supported by ANSI. The majority of databases solid adheres to the ANSI-92 standard. Almost each separate database uses some unique set of syntax, though very strongly similar to the ANSI standard. In most cases, this syntax is extension of the basic standard though there are cases when such syntax results in different results for different databases.

In the general terms, "SQL the database" is the general name for the relational database management system (RDMS). For some systems, "database" also concerns to group of tables, data, the configuration information which are essentially separate part from other, similar constructions. In this case, each installation of SQL of the database can consist of several databases. In other systems, they are mentioned as tables.

The table – construction of the database which consists of the columns containing lines of data. Usually tables are created to contain the connected information. Within the same database several tables can be created.

Each column represents attribute or set of objects attributes, for example identification numbers of employees, growth, color of machines, etc. Often concerning a column the term a field with specifying of a name, for example "in the field of Name" is used. The field of a line is the minimum element of the table. Each column in the table has a certain name, data type and the size. Column names shall be unique within the table.

Every line (or record) represents set of attributes of a specific object, for example, the line can contain identification number of the employee, the size of its salary, year of its birth, etc. Lines of tables have no names. To address a specific line, the user needs to specify some attribute (or a set of attributes), it is unique it identifying.

One of the major operations which are executed by dataful operation is selection of the information which is stored in the database. For this purpose the user shall execute a request (query).

Types of requests of data

There are four main types of requests of data in SQL which relate to so-called language of a manipulation data (DataManipulationLanguage or DML):

• SELECT – to choose lines from tables;

• INSERT – to add a line to the table;

• UPDATE – to change lines in the table;

• DELETE – to remove lines in the table;

Each of these requests has different operators and functions which are used to make some dataful actions. The SELECT QUERY has the most large number of options. There are also additional types of the requests used together with SELECT, the JOIN and UNION type. But so far, we will concentrate only on the main requests.

Use of a Select query for selection of the necessary data

To obtain information which is stored in the database the Select query is used. Basic action of this request is restricted to one table though there are constructions providing selection from several tables at the same time. To receive all lines of data for specific columns, the request of such look is used:

SELECT column1, column2 FROM table_name;

Also, it is possible to receive all columns from the table, using the podstanovochny sign "*":

SELECT * FROM table_name;

It can be useful in that case when you are going to choose data with a certain condition of WHERE. The following inquiry will return all columns from all lines where "column1" contains 3 value:

SELECT * FROM table_name WHERE column1=3;

3.Design and development of databases. Technology of programming of ORM. The distributed, parallel and heterogeneous databases.

Design of databases — process of creation of the database scheme and determination of necessary integrity constraints.

Main objectives of design of databases:

• Support of storage in a DB of all necessary information.

• A data acquisition possibility on all necessary requests.

• Abbreviation of redundance and duplicating of data.

• Support of integrity of the database.

Main design stages of databases

Conceptual design

Conceptual design — creation of a semantic domain model, that is information model of the highest level of abstraction. Such model is created without orientation to any specific DBMS and a data model. The terms "semantic model", "conceptual model" are synonyms.

The specific type and the maintenance of conceptual model of the database is defined by the formal device selected for this purpose. Graphic notations, similar to ER charts are usually used.

Most often the conceptual model of the database includes:

• description of information objects or concepts of data domain and communications in between.

• description of integrity constraints, that is requirements to admissible values of data and to communications in between.

Logic design

Logic design — creation of the database scheme on the basis of a specific data model, for example, a relational data model. For a relational data model data logical model — a set of diagrams of the relations, it is normal with specifying of primary keys, and also the "communications" between the relations representing foreign keys.

Conversion of conceptual model to a logical model is, as a rule, carried out by the formal rules. This stage can be substantially automated.

At a stage of logic design specifics of a specific data model are considered, but specifics of specific DBMS can not be considered.

Physical design

Physical design — creation of the database scheme for specific DBMS. Specifics of specific DBMS can include restrictions for naming of database objects, restrictions for the supported data types, etc. Besides, specifics of specific DBMS in case of physical design include a choice of the decisions connected to a physical medium of data storage (a choice of methods of management of disk memory, division of a DB according to files and devices, data access methods), creation of indexes etc.

What is ORM?

ORM or Object-relational mappingis a technology of programming which allows to transform incompatible types of models to OOP, in particular, between the data store and subjects to programming. ORM is used for simplification of process of saving objects in a relational database and their extraction, in case of this ORM itself cares for data transformation between two incompatible statuses. The majority of ORM tools considerably rely on meta data of the database and objects so objects need to know nothing about a database structure, and the database — nothing about how data are organized in the application. ORM provides complete division of tasks in well programmed applications in case of which both the database, and the application can work dataful everyone in the root form.

Fugure3- ORM`s work

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