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

Design patterns offer proven solutions to recurring software design challenges, promoting code reusability, maintainability, and efficiency. They can be categorized into three main types:

Behavioral Design Patterns

These patterns focus on communication and interaction between objects, enhancing flexibility. Examples include:

• Observer Pattern: Enables one-to-many dependencies, where changes in one object automatically notify dependent objects.
• Iterator Pattern: Provides sequential access to elements within a collection without exposing its underlying structure.

Creational Design Patterns

These patterns address object creation mechanisms, ensuring suitable instantiation processes. Examples include:

• Singleton Pattern: Restricts object creation to a single

Structural Design Patterns

Decorator - Adds additional functionality to a class

Adapter - 'adapts' one interface for a class into one that the client expects

Façade - creates a simplified interface from an existing one

Flyweight - A high quantity of objects share common properties to save space.

Bridge - decouples an abstraction from its implementation so that the two can vary independently.

Behavioral Design Patterns

Chain of Responsibility - Linked list of handlers

Command - Enables all the info for a request to be contained within a single object.

Interpreter - Developing domain specific languages

Iterator - Sequentially access elements of an aggregate object.

Mediator - Removes the need for classes to communicate with each other directly.

Observer... Continue reading "Structural and Behavioral Design Patterns in Software Development" »

Understanding the Internet: A Global Network

The Internet is a global network of interconnected computers that any device can join. It functions as a Wide Area Network (WAN), which is essentially a series of connected Local Area Networks (LANs).

Data packets are transmitted between computers using protocols that govern how information is sent and received.

Key Internet Technologies and Services

Technologies and services available over the Internet include:

• Web Pages: HTML documents presenting images, sound, and text, accessed via a web browser.
• Web Applications: Software accessed through a web browser.
• Native Applications: Applications developed for specific devices (e.g., smartphones), accessible without a browser.
• Email: Electronic mail communication.

Data Project Management: A Comprehensive Guide

Goal Setting: The Foundation of Project Planning

Every project requires a clear destination to determine its success. Goal setting is the first step in project planning, providing a roadmap for the project's journey.

Tools & Skills: Assessing Project Resources

The upper blocks of DR (Data Requirements) focus on evaluating the resources necessary for data project implementation. These resources include:

• Hard Resources: Data, software tools, processing
• Soft Resources: Skills, domain expertise, human resources for execution

Process & Value: Implementation and Delivery

The lower blocks of DR concentrate on project implementation and delivery. DR serves as a planning tool, helping project managers:

• Identify

Inserting Tables into Slides

In the Insert Object dialog box, click the Create From File option and click Browse to locate and choose the document or spreadsheet that contains the table. By default, the presentation software will insert the table. When you click OK, the entire document or spreadsheet is imported to your slide. Double-click the inserted text to remove extra text if the document contains more than the table. If you check the Link checkbox while inserting, after you update the table in the document or spreadsheet, then right click on the imported table in the presentation software, and select the option Update Link, the embedded table gets updated automatically. Drag and drop the table on the slide to position it.

Chart Design Principles

Convey... Continue reading "Embed and Link Objects in Presentations: Best Practices" »

1. What is recurrence for worst case of QuickSort and what is the time complexity in Worst case? Recurrence is T(n) = T(n-1) + O(n) and time complexity is O(n^2) 2. Suppose we have a O(n) time algorithm that finds median of an unsorted array. Now consider a QuickSort implementation where we first find median using the above algorithm, then use median as pivot. What will be the worst case time complexity of this modified QuickSort. O(nLogn)  3. Given an unsorted array. The array has this property that every element in array is at most k distance from its position in sorted array where k is a positive integer smaller than size of array. Which sorting algorithm can be easily modified for sorting this array and what is the obtainable time complexity?

Explanation

10.1 Pivot tables

What is a pivot table? It is one of the most powerful tools in Excel. They are also called “dynamic” because the data on them can be changed by rearranging or changing the position of the column and row headers in an easy and quick way.

The use of a dynamic table is to obtain information summaries from our data grid in order to be able to quickly analyze big volumes of information. These type of tables can be used in situations such as:

• When you have a table with rows that have different date and you need to organize the information by time periods (month, semester, etc.)
• When you need to change the arrangement in the rows or column cells to show different perspectives from the same data set.

Follow these steps to... Continue reading "Excel Pivot Tables, Search and Logic Functions, Macros" »

Business Values of Telecom Standardization for Operators

1. Multiple sources of supply (decrease risk of sole supplier dependencies/lock-in, improve choice at competitive prices).
2. Interoperability, e.g., multi-vendor networks, service interop.
3. Assurance that investment in technology should not abruptly change or fail.

Business Values of Telecom Standardization for Vendors

1. Network vendors can sell to all service operators, freed from vendor-specific R&D.
2. Reduce customization.
3. Build reputation / customer confidence - strong standards brand.
4. Larger markets from wide adoption, greater economies of scale.

Types of Standards Bodies

1. Accredited
2. Treaty-based
3. Partnerships

Telecom Acronyms Explained

1. ITU: International Telecommunication Union
2. IETF: Internet Engineering