Data Science and Music Technology Quiz

Data Storage

• Data storage is a broad topic encompassing several levels of memory
• This ranges from individual bits to mass storage devices.

1.1 Bits and Their Storage

• A Central Processing Unit (CPU) has two main parts, a control unit and an arithmetic logic unit (ALU).
• The control unit directs operations across the computer
• The arithmetic logic unit (ALU) executes arithmetic (+, -, ÷, x) and logical (AND, OR, XOR, NOT) operations.
• Registers are temporary storage areas in the CPU that hold instructions or data. -Registers are faster than main memory
• Registers are used for storing data, accepting data, and transferring data to and from memory.

Data Representation

• Bits (binary digits) are used to represent numbers, text characters, images, and sound.

Boolean Operations

• Boolean operations manipulate true/false values.
• Key Boolean operations include AND, OR, XOR (exclusive or), and NOT.
• Truth tables are used to define the behavior of these operations.

Gates

• Gates are electronic circuits that perform Boolean operations.
• They are the basic building blocks of computers
• VLSI (Very Large Scale Integration) is used to construct computers from these building blocks.

Storage Hierarchy

• Registers hold data immediately used with an operation.
• Main memory stores data and programs for immediate to near future access.
• Auxiliary memory stores data and programs for later use.

Binary Notation

• Binary notation uses 0s and 1s to represent numeric values, as opposed to the decimal system (0-9).

1.2 Main Memory

• Main memory is also called primary memory, internal storage, or primary storage.
• It temporarily holds instructions and data for the currently running program.
• Contents are lost if the computer power is turned off (volatile).
• Main memory is used to store instructions, data for running programs

Memory Cells

• A cell is a unit of main memory, typically 8 bits which is one byte.
• Most significant bit is the left-most bit in a memory cell
• Least significant bit is the right-most bit in a memory cell

Memory Addresses

• Each memory location has a unique address.
• Used by the CPU to store data and retrieve data from a particular location
• Addresses are typically numerical (though symbolic can be used as well).

Bits, Bytes, and Words

• A bit is a binary digit (0 or 1).
• A byte consists of 8 bits.
• Units of measurement for data storage: -1 kilobyte (KB) = 1024 bytes -1 megabyte (MB)=1024 kilobytes -1 gigabyte (GB) = 1024 megabytes -1 terabyte (TB) =1024 gigabytes -1 petabyte (PB) = 1024 terabytes

RAM and ROM

• RAM (Random Access Memory) has two types SRAM and DRAM.
• SRAM is faster, static, and not constantly refreshed.
• DRAM is used in most PCs, dynamic, and constantly refreshed by the CPU.
• ROM (Read-Only Memory) is non-volatile and data cannot be changed.

1.3 Mass Storage

• Mass storage, also called secondary storage.
• Includes Magnetic disk(Floppy Disks, Hard Disks, Tape) and Optical disk (Compact disks, DVD-ROM, Blue-ray Disks), and Flash Drives (Secure Digital (SD) Memory Card)

Data Organization in Hard Disks

• Data is organized into: -Tracks -Sectors -Clusters -Cylinders

Disk Access Speed

• Access time is the time it takes to access data from a disk. It is determined by seek time + rotational delay + data transfer

• Magnetic Tape Storage

• Data is stored as small magnetic spots. -3.5-inch tape wound on a reel

• 3.5-inch tape in data cartridge

• Cassette tapes

• Tape capacity is measured in characters per inch (CPI) or bytes per inch (BPI).

• Uses two (read/write and erase) heads

Storage categories comparison

• Disks are reliable and data is accessible directly
• Magnetic tapes are inexpensive, but data is accessed sequentially

Optical disk storage

• Metallic materials are spread over the surface of the disk.
• A laser hits the surface to create spots representing Os and 1s

Compact Disks

• CD-ROM drives only read data from CDs,
• CD-ROM stores about 700 MB per disk
• CD-R drives write to a disk only once
• CD-RW drives can erase and record repeatedly

Digital Versatile Disk (DVD)

• DVD drives can read CD-ROMs and have higher capacity than CDs.

Blue-Ray Disks

• Higher storage capacity than DVDs, with comparable speeds.

Flash Memory

-Nonvolatile RAM.

• Uses flash chips, commonly found in cellular phones and digital cameras.
• Requires less power and smaller than disk drives.
• Examples are Secure Digital (SD) Memory cards

Files

• Files are units of data in mass storage systems
• Consists of fields and key fields
• A physical record conforms with characteristics of the storage
• Logical records naturally occur as paragraphs or pages (logical divisions of files)
• Data such as characters, fields, records, and files make up Databases

File Storage and Retrieval

• Key is an identifying record (or set of records)
• A buffer holds data temporarily during transfer.

1.4 Representation of Information as Bit Patterns

• Information—text, numbers, images and sound—is represented in computers as bit patterns.

• Representing Text

• ASCII (American Standard Code for Information Interchange) uses 7-bit patterns. -Unicode uses 16-bit patterns, allowing representation of a wider range of characters than ASCII

• Representing Numbers

• Computers use binary notation to represent numerical values.
• Overflow and truncation can occur when using numbers too large/too small for the binary system

• Representing Images

• Bitmaps represent images as a grid of pixels.
• Shades of gray and color images are represented by combining bits within each pixel

• Representing Sound

• Sound is represented by sampling the amplitude of the sound wave at regular intervals.
• The data acquired from samples is represented in binary format
• Higher sample rates and bit depth result in higher quality sound reproduction

Large-Scale Data

• The amount of data, from commercial and scientific sources, has grown significantly.
• This growth results from advancements in data generation and collection technologies

Data Science

• Data science combines aspects of computer science, math, and statistics.

Skill sets for Data Science

Combining computer science skills, math/statistics skills, data science, and domain expertise is essential in the field

Classifying Tasks

• Predict credit card fraud in transactions
• Predict customer churn in telephone contracts
• Classify sky objects (stars/galaxies) from celestial surveys

Regression Tasks

• Predicting sales amount based on expenditure factors.
• Estimating wind speeds, using environmental variables like temperature, humidity, etc.
• Predicting stock market indices using trends in historical data values.

Clustering Tasks

• Segmenting market based on customer attributes (e.g., location, lifestyle).
• Grouping documents that shares common terms, to improve information retrieval and other data mining operations -Analyzing and summarizing large data sets. (e.g., classifying geographical areas based on different factors)

Data Science

• Dealing with large scale data -Analyzing large datasets for information.
• Creating models based on data that can predict information
• Applying data to real world issues.

Test your knowledge on the sample rates used in music CDs, the fundamentals of data collection in data science, and pseudocode logic. This quiz covers key concepts that bridge the worlds of audio quality and modern data practices. Prepare to challenge yourself on various topics related to music technology and data science.