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

At the Beginning

Hello, I'm Laura and I'm going to talk about recycling.

Important Oracle SQL Data Dictionary Views

Important Oracle SQL tablespaces views include: dba_tablespaces, dba_data_files, dba_tables, user_types, user_source.

Creating Complex Object Types

CREATE OR REPLACE TYPE direccion AS OBJECT(
    calle VARCHAR2(50),
    numero NUMBER(3),
    piso NUMBER(2),
    puerto VARCHAR2(1),
    codpostal NUMBER(5),
    localidad VARCHAR2(50),
    provincia VARCHAR2(50)
);

CREATE OR REPLACE TYPE persona AS OBJECT(
    dni VARCHAR2(9),
    nombre VARCHAR2(50),
    apellido1 VARCHAR2(50),
    apellido2 VARCHAR2(50),
    telefono NUMBER(9),
    fecha_nac DATE,
    direccion direccion
);

Creating Tables Using Object Types

CREATE TABLE agenda OF persona;

DESC agenda; -- Visualize table structure


CREATE TABLE agenda2

Resistors

• Longer side on positive
• Limit current through circuit
• Measured in ohms (Ω)

Voltage, Current, and Resistance

• Voltage (V): Exerted force to push electricity
• Current (I): Amount of electricity pushed (measured in Amps)
• Resistance (R): Constraints on the flow of electricity
• V = I*R, R=V/I, I=V/R

Diodes

• Act as stop-gap gates
• Ensure electron flow in intended direction

Motors

• Regular DC motors: Spin at various speeds
• Servo motors: Directional control, moving arm from controllable positions

Serial Communications

• Used to print values to Serial Monitor
• Good for troubleshooting

LEDs

• Light Emitting Diodes
• Light up when required forward voltage is found
• Intensity of light depends on current flow

Photodiodes

• Trip to reception of light, not emission of it
• Basics of solar

What is the Difference Between Principle - Principle of Operation?

Brayton Cycle

The continuous combustion cycle.

How Does Engine Thrust Vary?

Low temperature gives greater thrust.

Which Statement is True?

At lower engine speeds...

Static Thrust is Developed

Aircraft on the ground and stationary.

The Fan Bypass Ratio (BPR)

The mass ratio of air that passes...

P2 and P7 Sensors are Pickups for

Inlet and outer pressures.

Thrust

Increases with an increase in speed.

EPR (Engine Pressure Ratio) is

The main parameter that shows the thrust produced.

Compressor Inlet Screens

For protection against Foreign Object Debris (FOD).

Intakes are Designed to

Decelerate the free air stream.

What is the Shape of a Jet Engine Air Intake?

Divergent

Compressor Stall

Is the airflow separation... Continue reading "Jet Engine Fundamentals and Operations" »

The Motherboard: The Backbone of Your Computer

The motherboard is the central component of a computer, connecting all of its parts together. It serves as a platform for the CPU, memory, hard drives, optical drives, video card, sound card, and other ports and expansion cards.

Features of a Motherboard

• Supports various types of components
• Supports a single type of CPU and few types of memories
• Video Cards, Hard disks, Sound Cards must be compatible with the motherboard to function properly
• Motherboards, cases, and power supplies must be compatible to work properly together

Popular Motherboard Manufacturers

• Intel
• ASUS
• AOpen
• ABIT
• Biostar
• Gigabyte
• MSI

The CPU: The Brain of Your Computer

The CPU, or Central Processing Unit, is the brain of the computer. It handles... Continue reading "Motherboard and CPU: The Core Components of a Computer" »

Fossil Fuel Power Stations

Fossil fuels, such as coal, oil, and natural gas, are used to heat water in a boiler. Steam from the boiler turns a turbine, which is connected to the rotor of a generator. The generator produces electricity, which is transported by a network of high voltage power lines. After that, the steam goes to a condenser where it cools and becomes liquid water again. Finally, the water is pumped back to the boiler.

Combined Cycle Power Stations

Electricity is generated in two systems. In the first, natural gas is burned with compressed air. This produces superheated gases which turn a turbine to generate electricity. In the second, the hot gases from the first system are used to produce steam in a heat recovery boiler. Then the... Continue reading "Types of Power Stations: Fossil Fuels, Combined Cycle, Hydroelectric, Geothermal, and Solar" »

Java Book Class Example

Sorting and Displaying Books by Price

This code defines a simple Book class in Java and demonstrates how to sort and display a list of books by price in ascending order.

Book Class

The Book class has the following attributes:

• bookId: Unique identifier for each book.
• title: Title of the book.
• author: Author of the book.
• publisher: Publisher of the book.
• price: Price of the book.

The class provides a constructor to initialize these attributes, getters to access them, setters to modify them, and a toString() method to represent a Book object as a string.

Program3 Class

The Program3 class contains the main method, which performs the following actions:

1. Creates a list of Book objects.
2. Adds several book instances to the list.
3. Sorts the bookList

1. Definition of an Automated Control System:

   
   

It is a group of elements that are combined to optimize a process working together

2. What is a variable in an automated control system?

It is a magnitude (light, sound, temperature, pressure) that can be measured to be used in a program

3. How many sensors (variables) does the LEGO NXT Robot have?

4: distance, pressure/contact, light, and sound

4. How many outputs does the LEGO NXT Robot have?

3: (A, B, C) for motors.

5. What kind of battery does the LEGO NXT Robot have?

9v rechargeable

6. What is the variable in an automated heating system?

temperature

7. What is the difference between open & closed loop systems?

open loop systems are simple sequences regulated by time.

8. What kind of system (open or closed loop) is a heating

Plastics

Plastics are materials formed by chains of carbon and hydrogen atoms. We call the chains polymers, while the atoms that form them are called monomers.

Thermoplastics

Thermoplastic materials are plastics that are softened by heating and can be formed and melted as many times as we want. This is because their polymers have weak bonds. (Polyethylene (PE), Polystyrene (PS), PVC (polyvinyl chloride))

Thermoset Plastics

The polymers of thermoset plastics criss-cross to form networks. Because of this bond, the plastics can be shaped using heat; however, once they have been formed, they cannot be re-melted to create different forms. (Melamine, Bakelite, Polyester resins)

Elastomers

Elastomers are very flexible materials that recover their shape and... Continue reading "Understanding Plastics: Types and Manufacturing Processes" »