Notes, summaries, assignments, exams, and problems for Computers

What is APOO?

APOO (Analysis and Object-Oriented Programming) considers a problem and a solution from the perspective of objects, things, or concepts. APOO is the investigation of domain objects and their relationships.

What is OOP?

OOP (Object-Oriented Programming) is a logical solution in terms of software components and their collaborations and responsibilities.

UML Language

The UML (Unified Modeling Language) is the standard language for typesetting to view the results of the analysis and design.

Subactivities:

1. Define essential use cases.
2. Draw use case diagrams.
3. Refine the conceptual model.
4. Refine the glossary.
5. Set system sequence diagrams.
6. Set operation contracts.
7. Set state diagrams.

What is a Use Case Diagram?

A use case diagram is used to identify... Continue reading "Object-Oriented Analysis and Design Principles" »

Core Concepts of Artificial Intelligence

Defining Key AI Components

• Artificial Intelligence (AI): A study to perceive, reason, and act. Systems that think like humans, trying to understand how the human mind works. Systems based on rules.
• Intelligent Agent: An entity capable of perceiving its environment, processing these perceptions, and responding or acting in that environment rationally and appropriately.
• Prolog: A functional programming language based on logic.
• Rational Agent: Agent = Architecture + Program. The program depends on the environment in which it operates.

Types of Intelligent Agents and Programs

The agent program dictates how the agent chooses its actions:

1. Simple Reflex Agent

   Actions depend solely on the current perception and predefined

Network Resource Sharing Fundamentals

A network resource is a logical entity capable of action at the request of another. The use of shared resources can be performed through a network.

High-Speed Data Connectivity

Disk Management and Fiber Channel

For servers, Fiber Channel interfaces are important for fast disk connections with extreme speed specifications.

Fiber Channel technology is traditionally used for building Storage Area Networks (SANs). The Fiber Channel Standard is an interconnection technology designed for broadband communication. This standard consists of a set of standards developed by ANSI.

• Maximum distance allowed: 10 km.
• Protocols transported include: SCSI, IP, IPI, HIPPI, IEEE 802, and even ATM.

Managing Printing Resources

Local Area... Continue reading "Core Network Resources, Protocols, and Server Technologies" »

1. Data Models and Conceptual Schemes

The conceptual scheme within the ANSI/X3/SPARC framework aims to define the data and the relationships between them that will be computerized in a particular organization, subsequently translating this into a canonical schema. The primary challenge is defining the set of entities to be stored in the database (DB), a task dependent solely on the Database Administrator (DBA).

Recall the three conceptual models, often called semantic models:

• MER (Entity-Relationship Model)
• Binary Model
• RMT (Semantic Model)

Once the conceptual design is complete, the process moves to the logical design or definition of the canonical schema. This translation process is performed using logic models, also known as data models. The most... Continue reading "Database Fundamentals: Comparing Relational, Hierarchical, and Network Models" »

Web Engineering Models

Data Model

Compatible with the entity-relationship model and UML class diagrams.

Hypertext Model

• Composition: Site pages, content units of pages.
• Unit: Atomic content element, used to publish the information specified in data models.
• Navigation: Specified by links.
• Links: Between units of a page, between units of different pages, or between pages.
• Defines both the content and navigation.

Presentation Model

• The appearance of web pages.
• Does not include specific elements for conceptual modeling; notations are used.
• XML.
• The presentation is specified using XSL stylesheets.

Web Engineering UML-Based Methodology (UWE)

• Proposal based on UML and the Unified Process, adapted to the web.
• Specific object-oriented techniques are used.
• Proposes an

History of Windows NT

Windows NT was originally developed to be OS/2 3.0 before Microsoft and IBM discontinued their work on OS/2.

• Unlike Windows 3.1, which was a GUI running on MS-DOS, Windows NT is a standalone operating system.

It is based on a microkernel, supporting up to 4GB of RAM, FAT file systems, NTFS, HPFS, built-in network support, multiprocessor support, and C2 security.

Windows NT Features

• It is based on variations of the kernel of Mac UNIX. The microkernel architecture supports applications not originally designed for Windows NT.
• It manages basic operations systems and other layers above them.
• Supports five subsystems: Windows 32-bit, 16-bit Windows, DOS, POSIX, and OS/2.
• Functions as a Client-Server in a network environment.
• Allows development

Storage Devices

Storage Devices: devices that store information. They comprise:

Magnetic Disks

Magnetic disks: Hard drives, floppy disks have large capacity, non-volatile random access, but live slower. It is a closed box, partly comprising:

• Platters: Stored information resides here.
• Head: Reads and writes on the platters.
• Motors: Spin the platters and move the heads.

Components of Magnetic Disks

Platters: Glass, ceramic, or aluminum; joined by a shaft and a motor to rotate at 3600 and 7200 rpm, with a diameter of 5.5 inches.

Heads: Magnetic sensor that reads the charge and a magnet to change the charges for writing.

Spindle (Topic): Support for the disks.

Actuator: The motor that moves the heads.

Structure and Organization

Tracks (Structure-Runs): Concentric... Continue reading "Understanding Computer Storage Devices and Media" »

Fundamentals of Information Security

Core Security Principles

• Confidentiality (Privacy): Ensures information is not accessible to unauthorized individuals.
• Integrity: Guarantees information can only be modified by authorized personnel.
• Availability (Operability): Ensures information is accessible and usable when needed.

Common Information Security Threats

Software and System Vulnerabilities

• Bug: An error or flaw in a computer program or system that causes it to produce an incorrect or unexpected result, or to behave in unintended ways.
• Trojan: A type of malware that disguises itself as legitimate software, allowing external users unauthorized access to a computer system.

Network and Data Attacks

• IP Spoofing: The act of creating Internet Protocol (IP)

Criteria to organize files · quick-access necessary when a single record is accessed. -not needed if a file will be processed in batches. Easy to update-a file on CD-ROM updates and never ease storage is not considered economic. -minimum data redundancy. -redundancy can be used to speed up access. · a single-index · Maintenance cheaper. -fewer errors.· Reliability A directory can have subdirectories, thus forming a hierarchical structure in the shape of an inverted tree, is symbolized by a bar of division (/) Some directories on Linux: • / bin Contains executable programs that are part of the Linux operating system . Many Linux commands like cat, cp, ls, more and tar are located in this directory. • / bootIt contains the kernel (or... Continue reading "Parcial_2_antonio_B" »