CIS 350
data transfer rate=
(1/access time) * unit of data transfer
The supervisor is the portion of the OS that receives control and performs two important functions: ______ and _______
- calling the correct interrupt handler - transferring control to the scheduler
characteristics and their cost implications: speed volatility access method portability capacity
- cost increases as speed increases - cost increase as volatility decreases - cheapest to more expensive: serial, direct, parallel - portability increases cost - cost increases as capacity increases
interrupts can occur for a variety of reasons, including:
- executing a service call - a hardware-generate interrupt indicating an error - an interrupt generated by a peripheral device
A multitasking OS manages hardware resources to achieve the following goals:
- meet each program's resource needs - prevent programs from interfering with one another - use hardware and other resources efficiently
Advantages of virtual resource management:
- more tasks are completed because more programs are present - programs are simpler - scarce and/or expensive resources can be applied to their highest purpose and shifted rapidly in response to changing demands.
list several operating system functions
- serves as a central point of control over hardware and software resources - coordinates access to shared resources -implements access controls and authentication - provides a set of utility programs to perform functions needed by multiple application programs
What data items are typically included in a PCB?
- unique process identification number - current state of the process - events the process is waiting for - resources allocated exclusively to the process -machine resources consumed - process ownership and access privileges - scheduling priority or data for determining scheduling priority
Calculate the S/N ratio (in dB) given the following criteria: The channel length is 4.5 km The sender generates the signal at 60 dB The channel has a noise level of 22 dB at the sending end The channel adds 7.5 dB of noise per km
-94.75dB
Process groups are modular architecture. The alternative is monolithic which:
-Requires more resources (the ones allocated to idle modules) -Makes program design much more complex -Makes program update more complex (can't swap out smaller modules)
if the modification states of the is Yes- __________ No - _________
-The page in memory is written to disk (an area called the swap space, swap file, or page file) and the corresponding page table is updated -No write to disk is required but the page table must still be updated
What will be the parity bit given the following conditions? 0 1 1 0 1 1 0 1 Parity Method: Even Parity
1
Platter diameter is currently between ______ inches.
1 and 3
The sender encodes a bit value by sending a specific voltage. If the received voltage is above the threshold, the signal is assumed to contain a ____. If it is below it is assumed to contain a ____
1, 0
Assume you are working with a 800 x 600 24-bit color image. What is the amount of storage space required to save the image?
1,440,000 bytes
With any error detection method there are four possible outcomes per message:
1. An error occurs and is detected (good) 2. An error occurs and isn't detected (very bad) 3. No error occurs but one is detected anyway (bad?) 4. No error occurs and none is detected (good)
If all the text from the question appears on a printed page in 24-point Times New Roman font, what is the height of each letter
1/3 inch
______ inch is the standard pixel size, called a point.
1/72
Typical access times are _______ for DRAM and ______ for SRAM.
10 to 20 ns, 1 to 5 ns
Primary storage is typically faster than secondary storage speed by a factor of ____ or more.
10^5
calculate the maximum channel length (in km) given the following criteria: a. a fiber optic cable carries one signal b. the sender generates the signal at 45 dB c. the receiver needs a 7.5 dB S/N ratio for accurate reception d. the signal attenuates at 1.5 dB per kilometer
25 km
Repeaters are typically required every __ or __ km for single mode fiber optic cable
40-50
common size of CRC
64 to 1024 bits
the point of a positive peak is ____, the zero point between a positive and negative peak is _____ and the point of a negative peak is ____
90, 180, 270
Assume that you are working with a 1024 x 768 monochrome image. What is the amount of storage space required to save the image?
98304 bytes
A receiver informs a sender that data was received correctly by sending a _____ message. It informs the sender of a transmission or reception error by sending a ______ message
ACK, NAK
is most common character representation methods
ASCII
What does it mean that the service lay is a form of code reuse?
Application programs perform I/O and other functions by calling a subroutine or method that already exists in the OS - the application programmer reuses program code embedded in the operating system
three standard optical storage media that are written only during manufacturing are called
CD-ROM, DVD-ROM, BD
______ is an error detection method that treats an entire data block as a binary value divides that value by a binary key value, and appends the remainder to the data block as check data
CRC
______ is the latest widely used standard of twisted pair wire although ______ is more common because it was used for many years
Category 6a, Category 5
Current packaging is ______ is essentially a SIMM with independent electrical contacts on both sides of module
DIMMs
commonly used standards for video controller IDLs include _____ and ________
Direct3D, OpenGL
The two most widely used video controller IDLs are ______ and _________
Drect3D, OpenGL
Tapes are mounted in a tape drive, which is a slow parallel access device, for reading and writing.
FALSE (slow serial access drive)
In the ______ scheduling method, threads are dispatched in order of their arrival
FCFS
the ______ or _________ format is commonly used to compress still images
GIF, JPEG
first used _____ in the late 1970s and it grew to dominate computing by the end of the 20th century
GUI
Common bitmap compression formats include ________ and______ for still images and __________ for moving images.
Graphics Interchange Formal (GIF) , Joint Photographic Experts Group (JPEG) , Moving Picture Experts Group (MPEG)
a _____ compresses an image by rpelacing some inage components, such as lines and shapes, with equivalent drawing command
Image description language
commonly used flat plannel display types include ____, _______ and ______
LCD, LED, and plasma
____ are a more recent entrant to the flat panel display market. Modern LED displays, often called ______, achieve high-quality color display with organic compounds.
Light-emitting diodes (LEDs) , organic LED (OLED) displays
________ contains a matrix of liquid crystals sandwiched between two polarizing filter panels that block all light except light approaching from a specific angle. Modern LCDs use an _______ with one or more transistors for every pixel.
Liquid crystal display (LCD) , active matrix display
______ is a standardized method of encoding notes and instruments for communication with synthesizers and sound cards
MIDI
____ and _____ are promising new technologies for implement NVM that promise significant increases in longevity
MRAM, PCM
is a standard for storing and transporting control information between computers and electronic musical instruments.
Musical Instrument Digital Interface (MIDI)
When any interrupt is received, the CPU automaticaly suspends the currently executing thread, pushes current register values onto the stack, and transfers control to the _______
OS supervisor
_________ gives the ability to distribute compressed documents with complete authorial control over exact forms of the printed and displayed document, regardless of end users specific computer, OS, or printer.
commonly used two-dimensional bar-code formats include ____ and _______
PDF417, QR Code
_________ is an image description language designed mainly for printed documents, although it can also be used to generate video display outputs.
PostScript
____ and _______ are commonly used image description languages for documents
PostScript, PDF
Components of a video controller include display generator circuitry, software stored in ROM, a video processor, and ____
RAM
The main advantage of ______ is its high raw data transfer capacity and the mobility afforded by avoiding wired infrastructure
RF transmission
_____ is the earliest type of NVM, with data content written permanently during manufacturing
ROM
oldest to newest ROM technologies
ROM, PROM, EPROM, EEPROM
A channel's _____ describes the mathematical relationship between noise power and signal power
S/N ratio
serial transmission standards, including ____ and _____, are replacing parallel transmission standards for connecting secondary storage devices and controllers
SATA and SAS
standards for high speed and low latency communication between servers and secondary storage devices include _____, ______ and ________
SCSI, SAS, and infiniband
_____ replaced DIP in late 1980s which incorporates multiple memory chips on a tiny printed circuit board.
SIMMs
Modern desktop and laptio computers generally use memory packaged on small standardized circuit boards called _____
SIMMs or DIMMs
A channel's effective speed limit is determined by the power of the data-carrying signal in relation to the power of noise in the channel. This relationship is called the ______ which is measured at the channel's receiving end or at specific distance from the sender, usually in units of signal power called decibels
Signal-to-noise ratio (S/N)
is a read-ahead RAM that uses the same clock pulse as the system bus. Read and write operations are broken into a series of simple steps, each of which can be completed in one bus clock cycle
Synchronous DRAM (SDRAM)
____ is more cost effective and ____ is more efficient
TDM, FDM
A magnetic storage device converts electrical signals into magnetic charges, captures the magnetic charge on a storage medium, and later regenerates an electrical current from the stored magnetic charge
TRUE
RAM is fabricated in the same manner as microprocessors
TRUE
__________ enables a flat panel display to function as both an input and output device. The most common touchscreen technology is based on ________ which is the ability of a substance or object to hold an electrical charge.
Touchscreen technology , capacitance
Parity checking has high ______ for transmitted data since transmission errors ten to affect adjacent bits.
Type I
for any error detection method, a decrease in _____ is accompanied by an increase in ____ error
Type I error, Type II error
the probability of not detecting a real error is called _____ (false negative). the probability of incorrectly identifying good data as an error is called ______
Type I error, Type II error
In _____ program memory references correspond to physical memory locations. In ____, the CPU must calculate the physical memory location that corresponds to a program memory reference
absolute addressing, indirect addressing
A read/write head is mounted on an ______ for each side of each platter.
access arm
in a magnetic or optical disk drive, a read/write head is mounted on the end of a ____
access arm
Storage device speed is called ____
access time
Storage device speed is called ________ which is the time required to perform one complete read or write operation.
access time
____ is typically stated in milliseconds for secodnary storage devices and nanoseconds for primary storage deevices
access time
Video display colors are called ________(RGB) and their inverse colors are called _________ (CMY). Combining all three can generate _____. A separate black dye is, identified by the letter K, is generally used.
additive colors, subtractive colors, black
the process of converting an address operand into a physical address in a memory partition or page frame is called _______
address resolution or address mapping
A CPU's or computer's ______ is the highest numbered storage byte that can be represented
addressable memory
Advantages and disadvantages of twisted-pair wire
advantages: low cost and ease of installation disadvantages: high susceptibility to noise, limited transmission capacity because of low bandwidth, and low amplitude limit.
_____ is a measure of peak signal strength
amplitude
is a measure of wave height or power- maximum distance between a wave peak and its zero value
amplitude
_______ represents bit values as specific wave amplitudes
amplitude modulation
________ encodes data by varying the magnitude of wave peaks in an analog signal
amplitude modulation or AM
_____ represents bit values as specific wave amplitudes and is sometimes called ______
amplitude modulation, amplitude-shift keying
three characteristics of a sine wave
amplitude, phase, frequency
A _______ signal can encode an infinite number of possible numeric values
analog
Sound is an ______ that must be converted to digital form for computer processing or storage.
analog signal
An ______ uses the full range of a carrier wave characteristic to encode continuous data values
analog signal.
accepts a continuous electrical signal representing sound, samples it at regular intervals, and outputs a stream of bits representing the samples.
analog-to-digital converter
A _____ converts analog sound waves into a digital representation
analog-to-digital converter or ADC
The surface area allocated to store a bit is called
areal density
the _____ of a magnetic or optical storage medium is the ratio of bits stored to a unit of the medium's surface area
areal density
sender and receiver devices are separated by greater distances and each devices has its own clock. Doesnt send continuous streams of data.
asynchronous communication
______ is loss of signal strength as it travels through a transmission medium
attenuation
______ is the reduction in signal strength (amplitude) caused by interactions between the signal's energy and the transmission medium
attenuation
is the reduction in signal strength (amplitude) caused by interactions between the signal's energy and the transmission medium.
attenuation
A device that generates spoken messages based on text input is called an ______
audio response unit
a device that generates spoken message based on text input is called a __________
audio response unit
the time required to move between two sectors separated by an average number of recording surfaces, tracks, and sectors
average access delay
is the sum of average access delay and the time required to read one sector
average access time
A channel's _____ is the difference between the highest and lowest frequencies that can be transmitted
bandwidth
The difference between a signal's maximum and minimum frequencies is called the signal
bandwidth
A ________ detects specific patterns of bars or boxes. The simplest type of bar code contains a series of vertical bars of equal length but varied thickness and spacing. To detect these bars, bar-code readers use _________ that sweep a narrow laser beam back and forth across the bar code.
bar-code scanner , scanning lasers
______ are installed much like OSs (directly) but provide only minimal OS-type functions, such as the capability to start and stop VMs and manage physical resources on behalf of VMs.
bare-metal hypervisors
________ describes architecturers that store the most significant byte at the lowest memory address. _______ describes architectures that store the least significant byte at the lowest memory address
big endian, little endian
The _____ endian storage format places the _____ byte of a word in the lowest memory address. THe _____ endian storage format places to ____ byte of a work in the lowest memory address
big, most significant little, least significant
A _____ signal is a discrete signal that can encode only two possible values
binary
can represent only one of two possible values in each signal event
binary signals
As transmission speed is increased, the duration of each bit in the signal, known as _____, decreases
bit time
A stored set of numbers describing the content of all pixels in an image is called a_________
bitmap
in a computer, an image is stored as a ____, with each pixel represented by one or more numbers
bitmap
At the most fundamental level, a message is simply a sequence of ______
bits
is generic term for describing secondary storage data transfer units. Typically in bytes.
block
______ generates a _____ consisting of a single parity bit for each bit position in the group of characters or bytes
block checking, block check character
Parity checking can be expanded to groups of characters by using ______, also called _____. To implement this method, the sendign device counts the number of 1-valued bits at each bit position in a block then combines parity bits for each position into a ________ .
block checking, longitudinal redundancy checking, block check character
when a thread makes an I/O service request its placed in the _____ state until processing of the request is finished
blocked
the thread is in _____ when it is waiting for a resource or for an error to be resolved, thus not eligible for the running state
blocked state
high bandwidth
broadband
unichannel transmission of a single message to multiple recipients is called _____
broadcast mode
in a touchscreen that uses _____ , matrix of capacitors layered above or within the display panel is charged and reacts to presses from fingers and other electrically conductive objects
capacitance
A _____ wave transports encoded data through a transmission medium
carrier
a wave with encoded bits is called a ______ because it transports bits from one place to another
carrier wave
_______ cabling meets an industry standard that specifices four twisted-pairs and can support data transmission rates up to 1 Gbps
category 6e
Electrical current is routed through the _______ layer to the ________ layer, which is composed of organic compounds that emit red, green, or blue light, depending on their chemical composition. The ________ layer transmits electrical current to the _____ layer, which is connected to the negative side of the power supply. The ________ layer is plastic and conductive polymers are used for the cathode and anode.
cathode , emissive layer, conducting, anode, transparent
Like maximum signal frequency, ______ bandwidth determines the raw data transfer rate
channel (or medium)
A display device's ______ is the number of colors that can be displayed simultaneously
chromatic depth
most local phone service uses _____ swithcing to route messages from a wired home phone to the local phone-switching center
circuit
for most disk drives, the unit of data access and transfer is a ____ or _____
clock, sector
______ Cable contains a single copper conductor surrounded by a thick plastic insulator, a metallic shield, and a tough plastic outer wrapping
coaxial
contains a single copper conductor surrounded by a thick plastic insulator, a metallic shield, and a tough plastic outer wrapping
coaxial cable
the service layer is a form of ______
code reuse
the capability to accept and hold a magnetic charge.
coercivity
A _____ message contains instructions that control some aspect of the communication process
command
Through the ____ layer, a user or system administrator can run application and OS utility programs and manage system resources, such as files, folders, and I/O devices
command
through the ____ layer, a user or system administration can run application and OS utility programs and manage system resources, such as files, folders, and I/O devices
command
a set of commands and syntax requirements is called a _____
command language
A set of commands and syntax requirements is called a _____
command language.
the _____, ______ and ______ are the main layers of an OS
command layer, service layer, kernel
The _____, sometimes called the ____, is the user interface to the OS. Through this layer, a user or system admin can run application and OS utility programs and manage system resources, such as files, folders, and I/O devices
command layer, shell
A _______ consists of a sending device, a receiving device, and the transmission medium connecting them
communication channel
is a set of rules and conventions for communication.
communication protocol
Main advantage of MIDI is its _______
compact storage format
One way to address problem of fragmented space is to relocate all programs in memory periodically in a process called ______
compaction
One way to address the problem of fragmented free space is to relocate all programs in memory periodically in a process called
compaction
A __________ signal is created by combining multiple simple signals
composite
a signal created by combining multiple simple signals
composite (or complex) signal
on a computer with a single CPU, multitasking is achieved by _____ execution of multiple processes
concurrent
When memory allocation is _____, it means all portions of the program and OS are loaded into sequential locations in memory
contiguous
______ files make for a better performing system
contiguous
_______ means all portions of the program and OS are loaded into sequential locations in memory. No breaks
contiguous
with _____ all portions of a process must be loaded into sequential physical memory partitions
contiguous memory allocation
electrical signals are usually transmitted through ________ because its inexpensive, highly conductive, and easy to manufacture.
copper wire
______ is noise added to the signal from EMI generated by adjacent transmission lines in a parallel communication channel
crosstalk
noise added to the signal transmitted through an electrical transmission line or an RF band from EMI generated by adjacent lines or bands
crosstalk
Pointing devices can be used to enter drawings into a computer system or control the position of a _______ on a display device.
cursor
is the most widely used error-detection method. It produces BCC for a group of character or bytes and unlike block checking, this character is usually much larger than 8 bits and is generated by a more complex mathematical algorithm
cyclic redundancy checking
A ________ consists of all tracks at an equivalent distance from the edge or spindle on all platter surfaces.
cylinder
______ consists of all tracks at an equivalent distance from the edge or spindle on all platter surfaces
cylinder
_______ vary in format and content and can include any primitive CPU data types or complex data types. A ________ contains instructions that control some aspect of the communication process.
data messages, command messages
The ____ rate is the speed at which data can be moved to or from a storage device over a communication channel
data transfer
the data transfer rate of a magnetic or optical disk drive can be calculated by dividing 1 by the drive's access tiem and multiplying the result by the
data transfer unit size
average access time can usually be improved by ____ files stored on a disk
defragmenting
device at the end of a multiplexed channel that extracts individual message streams ("conversations" among different senders/receivers) and copies them onto independent non—multiplexed channels
demultiplexer
THe functions of the kernel are performed by a set of ________, which enable the service layer to "talk" to multple devices of the same type in the same way
device drivers
Data is represented and processed within the CPU as ______
digital electrical signals
can contain one of a finite number of values in each signal event
digital signal (discrete signal)
are microprocessors specialized for processing continuous streams of audio or graphical data. Commonly embedded in audio and video hardware.
digital signal processor (DSP)
performs the reverse transformation accepting a stream of bits representing sound samples and generating a continuous electrical signal that can be amplified and routed to a speaker.
digital-to-analog converter
the benefits of subdividing large processes into smaller ones are subject to the law of ________
diminishing returns
utility reorganized disk content so that a file's contents are stored in sequential sectors, tracks, and platters.
disk defragmentation
the act of giving control of a CPU to a ready thread is called ______
dispatching
the act of selecting a running thread and loading its register contents is called _____ and is performed by the _____
dispatching, scheduler
____ is any change in a signal characteristic caused by components of the communciaiton channel
distortion
changes to the data signal caused by interaction with the communication channel.
distortion
_____ creates an interlocking pattern of colored pixels that fools the eye into thinking a uniform color is being displayed
dithering
_____ is a process that generates color approximation sby placing small dots of different colors in an interlocking pattern
dithering
________ is a process that generates color approximations by placing small dots of different colors in an interlocking pattern. Gray scale dithering is usually called _______
dithering, half-tonigh
a _____ printer moves a print head containing a matrix of pins over the paper
dot matrix
A _______ moves a print head containing a matrix of pins over the paper.
dot matrix printer
a video display's resolution is described by the units ______
dots per inch or dpi
Multiple disk drives can be enclosed in a single storage cabinet; this arrangement is referred to as a _______
drive array
• Early packages were _______ installed on expansion cards or directly in motherboard.
dual-inline package (DIP)
______ stores each bit by using a single transistor and capacitor. Capacitors lose their charge quickly so they require a fresh infusion of power thousands of times per second. each refresh operation is called a _______
dynamic RAM (DRAM), refresh cycle
A net or ________ describes the transmission capacity actually achieved with a communication protocol
effective data transfer rate
the term ______ describes the maximum number of bits r bytes per second that the channel actually achieves with a specific communication protocol
effective data transfer rate
_______ is the main cause of attenuation with electrical signals and transmission media
electrical resistance
noise can be introduced into copper, aluminum, and other wire types by _________. This can be produced by a variety of sources, including electric motors, radio equipment, and nearby power or communication lines. it is the "extra" signal added to the original signal during transmission by leakage into the medium
electromagnetic interference
_____ cant affect optical signals but can affect electrical or RF signals
electromagnetic interference or EMI
A crucial component of any communication protocol is a method for detecting and correcting ________ in data transmission, reception, or interpretation
errors
Under ______ parity, the sender sets the parity bit to 0 if the count of 1-valued data bits is even or to 1 if the count of 1-value data bits is odd
even
Under _______ parity, the sender sets the parity bit to 0 if the count of 1-valued data bits is even or to 1 if the count of 1-valued data bits is odd
even
the sender sets the parity bit to 0 if the count of 1-valued data bits is even or to 1 if the count is odd.
even parity
with parity checking, sender and receiver must agree whether error detection is based on ____ or ______
even parity, odd parity
_______ scheduling assigns a priority level to each process or thread
explicit priority
4. Moving image quality improves as the number of frames per second (fps) decreases
false
6. A monochrome display can display black, white, and many shades of gray in between, so it requires 8 bits per pixel
false
A signal wire completes an electrical circuit between sending and receiving devices
false
All image formats are lossless
false
All printers and output devices use a standard language for all operating systems called the Universal Display Language
false
CRTs are the most energy efficient displays available on the market today
false
Circuit switching makes efficient use of channel capacity in most data transmission situations
false
Coercible material per sector is greater at the center than in the platter edge
false
Magnetic tape and disk are considered volatile storage media
false
Multitasking operating systems are not the norm for general-purpose computers
false
Narrowband channels in a single broadband channel must use the same signaling methods, communication protocols, and transmission speeds
false
Noncontiguous memory allocation uses small fixed-size partitions, usually no larger than 124 KB
false
Phase is a wave characteristic that's fundamentally the same as amplitude or frequency
false
Unlike block checking, CRC cannot product a BCC for a group of characters or bytes
false
Wait states increase CPU and computer system performance
false
memory allocation is less complex when the OS supports multitasking
false
the act of giving control of a CPU to a ready thread is called engaging
false
the only portion of a process that must be in memory at any point during execution is the next instruction to be fetched
false
Unlike block checking, CRC cannot produce a BCC for a group of characters or bytes
false
Coaxial cable is the most common transmission medium for phone and local area network (LAN) connections
false (twisted pair)
An analog signal can contain one of a finite number of possible values
false- infinite
Speech recognition systems are user-independent
false- user dependent
contains strands of light-conducting filaments made of plastic or glass
fiber optic cable
software programs stored permanently in ROM are called
firmware
When ______ schedulig, the scheduler always dispatches the ready thread that has been waiting the longest
first come first served
Most common NVM used today is _______. Write performance is slower than DRAM. Every write is mildly destructive.
flash RAM
is an electrical switch that remembers its last position.
flip flop
A collection of characters of similar style and appearance is called a _____
font
a collection of characters of similar style and appearance is called a ______
font
______ occurs when memory partitions allocated to a single process or purpose are scattered throughout physical memory
fragmentation
is the number of cycles occurring in 1 second and is measured in hertz.
frequency
the _______ of a sine wave is measured in hertz
frequency
______ encodes data by varying the distance between wave peaks in an analog signal
frequency modulation or FM
_______ represents bit values by varying carrier wave frequency while holding amplitude constant. It is also called _____
frequency modulation, frequency-shift keying
multiple messages can be transmitted on a single transmission line or circuit by _____ multipleixing or _____ multiplexing
frequency-division, time-division
Under ______ a single broadband channel is partitioned into multiple narrowband subchannels. Each subchannel represents a different frequency range and they are transmitted in each subchannel at a fixed frequency range.
frequency-dvidision multiplexing
In ____ mode, the receiver can communicate with the sender at any time over the second transmission line, even while data is still being transmitted on the first line.
full-duplex
The inefficiencies of half-duplex mode can be avoided by using two signal wires called _____, where the receiver can communicate with the sender at any time over the second transmission line, even while data is still being transmitted on the first line.
full-duplex mode
_____ mode implements two way transmission with two separate communication channels; ______ mode implements two way transmission with only one communication channel
full-duplex, half duplex
_______ touchscreen input interprets a sequence of touch information as a single command
gesture-based
______ also called _____, routes signals between two locations through a physical connection
guided transmission, wired transmission
uses a single shred channel, and each node takes turns using the transmission line to transmit and receiv
half-duplex mode
the three components that are summed to calcuate average access time for a disk drive are
head to head switching time, track to track seek time, rotational delay
accurate high-speed transmission and reception of digital square waves requires ______
high bandwidth
Higher bandwidth implies _____ data transfer rates
higher
A _______ is an OS that enables dividing a single physical computer or cluster into multiple virtual machines
hypervisor
_____ is an OS that enables dividing a single physical computer or cluster into multiple virtual machines
hypervisor
Printers create complex images using a __________ so that the printer can scale the image easily
image description language
_____ can print each character as its received, although small buffers are commonly used to improve performance
impact printers
As the number of active processes increases, the system overhead _____
increases
_____ areal density also reduces coercible material per bit and risks having the sorted charge fall below the read threshold. Therefore, more coercible medium coatings and more precise positioning of read/write head over storage medium must accompany increased areal density.
increasing
A ______ printer forces ink onto a page by heating it or forcing it out with a piezoelectric membrane
inkjet
A ______ printer uses droplets of ink dispensed by either heat or an electromechanical process
inkjet
______ are the most common printing technology and prints with liquid ink placed directly onto paper.
inkjet printers
speed and capacity are _____: a faster communication channel has a higher transmission capacity per time unit than a slower channel does.
interdependent
A _____ causes the currently executing process to be _____ and control to be passed to the _____
interrupt, pushed, supervisor
Type I and Type II errors are _____ related
inversely
The _____ is the OS portion that manages resources and interacts directly with computer hardware via device drivers and logical commands
kernel
Keyboards use an integrate microprocessor, called a_________ to generate bit stream outputs. When keys are pressed, a keyboard controller generates output called a _______, a 1-or2-byte data element representing a specific keyboard event.
keyboard controller,
Keyboards use an integrate microprocessor, called a_________ to generate bit stream outputs. When keys are pressed, a keyboard controller generates output called a _______, a 1-or2-byte data element representing a specific keyboard event.
keyboard controller, scan code
A _____ operates with an electrical charge and the attraction of ink to this charge.
laser printer
Color laser output uses three separate print generators (____________)
laser, drum, and laser modulators
_____ describes any method that intermixes clock synchronization information with encoded bit values
line coding
______ methods such as 8b/10b and 64/66b add extra signal transitions to a stream of data bits to ensure sender and receiver clocks remain synchronized
line coding
After sending a message, the first node signals its intent to cease transmission by sending a special control message called a ______
line turnaround
In half-duplex mode after sending a message, the first node signal its intent to cease transmission by sending a special control message called a ________
line turnaround
during half duplex transmission, sender and receiver switch roles after a _____ message is transmitted
line turnaround
what is the event sequence when a process or thread reads from a file?
look on page 406
All compression methods are _______, meaning they result in some loss of image quality.
lossy
Tendency of magnetically charged particles to lose their charge over time is called
magnetic decay
is the tendency of magnetically charged particles to lose their charge over time.
magnetic decay
is a single device with rigid platters, access arms and read/write heads, a motor to spin the platters, a servo to move the access arms, and all the electronics needed to control the drive, read and write sectors, and communicate with the system bus.
magnetic disk drive
_____ are flat, circular platters with metallic coatings that are rotated beneath read/write heads.
magnetic disk media
occurs when the polarity of adjacent bits is opposite so their magnetic fields tend to cancel out the charge of both areas.
magnetic leakage
data stored on magnetic media for long periods of tiem might be lost because of ____ and _____
magnetic leakage, magnetic decay
is a ribbon of plastic with a coercible coating.
magnetic tape
scans for light or dark marks at specific locations on a page
mark sensor
Volatility is not a binary characteristic, it's a ___________
matter of degree
is the fastest rate the drive can support and assumes sequential access to sectors.
maximum data transfer rate
defines how message bits are encoded and transmitted across the communication media
media control
the difference between the maximum and minimum frequencies that can be propagated through a transmission medium is called the _______
medium bandwidht
attenuation is proportional to the _______
medium's length
_______ is the assignment of specific memory addresses to system software, application programs, and data
memory allocation
__________ refers to protecting memory allocated to one program from unauthorized access by another program
memory protection
is a unit of data or information transmitted from a sender to a recipient. They can be categorized into data messages and command messages.
mesage
A _______ is a unit of data or information transmitted from a sender to a recipient
message
A _________ is a unit of data or information transmitted from a sender to a recipient
message
defines the content and format of data and command messages
message content
Type I error is also called _____ and type II error is also called ______
miss rate, false positive rate
the term ______ describes encoding data as variations in one or more physical parameters of a signal
modulation
A _____ display can display one of two colors, so it requires only 1 bit per pixel. A ________ display can display black, white, and many shades of gray in between. The number of distinct colors or gray shades that can be displayed is sometimes called the _______
monochrome, gray scale, chromatic depth
________ output is when only one frequency can be generated at a time. _______ is many different frequencies and different notes.
monophonic, polyphonic
SRAM is _____ expensive than DRAM. DRAM is ______ with more memory cells packed into each chip. DRAM is _______ than SRAM because of refresh cycles
more, simpler, slower
When considered as a byte sequence, the leftmost byte is called the ______ and the rightmost byte is called the _______
most significant byte, least significant byte
______ is a technique for embedding multiple bit values in a single wave characteristic, such as frequency or amplitude
multilevel coding
______ uses more than two signal characteristic levels to encode multiple bits in a single signal
multilevel coding
is a technique for embedding multiple bit values in a single wave characteristic, such as frequency or amplitude.
multilevel coding
______ cable can be constructed of glass or plastic
multimode fiber optic
has an optical fiber with a large diameter, compared with the wavelength of the light signals they carry
multimode optical cable
device that accepts multiple incoming independent message streams from separate channels and combines them for transmission over one multiplexed channel
multiplexer
A ____ OS supports multiple active processes or users
multitasking
OS support for running multiple program simultaneously is called
multitasking
OS support for running multiple programs simultaneously is called _____
multitasking
____ enables servers to work on hundreds to hundreds of thousand of processes at the same time, each dedicated to a specific user or task
multitasking
A ______ process contains subunits that can be executed concurrently or simultaneously
multithreaded
A process or program that divides itself into multiple threads is said to be ______
multithreaded
Access times of primary storage devices are generally expressed in _______. And for secondary are expressed in ______ or microseconds.
nanosecond, milliseconds
low bandwidth
narrowband
If ASCII control characters are used, a ______ control character is sent if errors are detected, and an _______ control character is sent if no errors are detected
negative acknowledge (NAK), acknowledge (ACK)
in a communication channel, ______ refers to unwanted singal components added to the data signal that might be interpreted incorrectly as data
noise
refers to unwanted signal components added to the data signal that might be interpreted incorrectly as data
noise
Under a ______ memory allocation scheme, portions of a single process might be physically located in scattered partitions of main memory
noncontiguous
_______ uses small fixed-sezed partitions, usually no larger than 64 KB, although 250 MB partitions are assumed to simplify the discussion and figures in this section
noncontiguous allocation
Memory devices comprised of semiconductors and other forms of RAM with long-term or permanent data retention are generically known as ___
nonvolatile memory
A storage device or medium is ______ if it holds data without loss over long periods and is _________ if it cant reliably hold data for long periods.
nonvolatile, volatile
what tricks can be played to minimize difference of SRAM and DRAM being slower than CPU?
o Read-ahead memory access (pre-fetch next memory location) o Synchronous read operations o On-chip caches
the sender sets the parity bit to 0 if the count of 1-valued data bits is odd . The sender sets the count to 1 if even
odd parity
In indirect addressing, the content of a _____ is added to calculate the corresponding physical memory address
offset register
______ encodes bit values with rapid pulses of electrical or optical power
on-off keying
square waves can be generated by rapidly switching an electrical or optical power source
on-off keying (OOK)
The _______ is the most important software component installed on any computer system
operating system
__________ devices combine optical-scanning or digital camera technology with a special-purpose processor or software to interpret bitmap content.
optical character recognition
A _____ generate bitmap representations of printed images
optical scanner
An _______ generates bitmap representations of printed images. A bright white light shines on the page or other flat surface, and reflected light is detected by an array of photo sensors.
optical scanner
Primary advantages of ______ compared with magnetic storage are higher areal density and longer data life.
optical storage
A _____ display achieves high-quality color display with organic compounts
organic LED or OLED
the ____ layers of an OS provide services to application programs or directly to end users
outermost
THe ______ layers provide services to application programs or directly to end users. The ____ layer encapsulates hardware resources- controlling and managing access by users and applications
outermost, innermost
most networks use _____ switching to enable senders and receivers to efficiently share a single communication channel
packet
the most common type of TDM, divides messages from all users or applications into small pieces called packets
packet switching
messages transmitted by time division multiplexing are divided into _____ before physical transmission
packets
A _____ is the unit of memory read from or written to the swap space
page
Each ____ is a small fixed-size portion of a program, normally between 1 and 4 KB.
page
A ______ occurs when a process or thread references a memory page not currently held in memory
page fault
in virtual memory management, memory references by a process must be converted to an offset in a _____
page frame
A reference to a page held in memory is called a _____ and a reference to a page held in secondary storage is called a ______
page hit, page fault
_____ is where a page in memory is removed to make room for the needed page
page swap
____ stores information about all pages of a single process
page table
in virtual memory management, a memory page's location is determined by searching a ______
page table
_____ store information about page locations, allocated page frames, and secondary storage space
page tables
Virtual memory management divides a program into partitions called _______
pages
virtual memory management divides a program into partitions called ____
pages
A _______ is simply a table of colors
palette
Most common display surfaces are ______ and _________ displays
paper and flat panel
_____ transmission uses multiple lines to send multiple bits simultaneously
parallel
_______ transmission uses a separate transmission line for each bit position
parallel
can simultaneously access multiple storage locations.
parallel access
adapts the technique to carry multiple parts of a message simultaneously
parallel transmission
the original process is called the ______, and the newly created process is called the ______
parent process, child process
In _____, an error detection bit is added to each character or byte, and the bit value is determined by counting the number of 1 bits
parity checking
Usually indicates completion of a previous processing request - currently running thread moves to ready state and thread(s) that were waiting for the peripheral device move from blocked to ready state
peripheral device
is a specific time point in a wave's cycle. it is measured in degrees
phase
represents bit values as the instantaneous changes in the phase of a carrier wave
phase shift modulation
a _____ is a basic component of human speech
phoneme
human speech consists of a series of sounds called _____, roughly corresponding to the sounds of each letter of the alphabet
phonemes
A _____ is a small device in optical scanners and digital cameras that converts light into an electrical signal
photosensor
Light reflected from a mark, a symbol, or an object is reflected into a ________
photosensor
A computer system's _______ is the actual number of memory bytes that are physically installed in the machine
physical memory
Modern displays are made up of cells, the smallest unit of which we call the __________
pixel
each cell in a video display surface's matrix represents a _____
pixel
Each cell in the matrix represents one part of an image, called a ________. For _______, a pixel is either empty or contains one or more inks or dyes. For ________, a pixel displays no light or light o specific color and intensity.
pixel, printed output, video display
Inkjet and laser printers use _____ as the fundamental output unit, so more complex communication methods are required.
pixels
A _____ display illuminates a pixel using excited gas and a colored phosphor
plasma
In a ________, each pixel contains a gas that emits ultraviolet light when electricity is applied. They're brighter and have a wider viewing angle than LCDs, but they require more power than LCDs.
plasma display
A ______ is a printer that generates line drawings on wide sheets or rolls of paper. They can handle paper widths up to 64 inches.
plotter
A ______ is 1/72 of an inch and is considered a standard pixel size
point
font size is measured in units called
points
A _____ sound card can generate multiple notes simultaneously. A _____ sound card can generate only one note at a time
polyphonic, monophonic
_______ capture devices differ in the degree of embedded computer power.
portable data
Access arms of equal length are attached to a __________ which moves the access arms so that read/write heads can be positioned anywhere between the outermost track and innermost track.
positioning servo
In ________ scheduling, a thread can be removed involuntarily from the running state.
preemptive
_____ scheduling refers to any type of scheduling in which a running thread can lose control of the CPU to another thread
preemptive
In _______ a thread can be removed involuntarily from the running state
preemptive scheduling
_________ devices are generally volatile and ______ are nonvolatile.
primary storage, secondary
_______ determines which ready thread should be dispatched to the CPU according to one or more of the following methods: first come first serve, explicit priority, shortest time remaining
priority based scheduling
A ____ is a unit of executing software thats managed independently by the OS and can request and receive hardware resources and OS services
process
A _____ is a unit of executing software that's managed independently by the OS and can request and receive hardware resources and OS services.
process
A _________ is a unit of executing software that's managed independently by the OS and can request and receive hardware resources and OS services
process
The OS keeps track of each process by creating and updating a data structure called a __________
process control block (PCB)
information about a process's execution state, such as register values and process status, are stored in a ______
process control block or PCB
A group of processes descended from a common ancestor, including the common ancestor itself is called a _______
process family
the list of PCBs, sometimes called a _____ is often searched by OS components.
process queue or process list.
are another example of 2D bar codes. They're widely used on posters and printed material to provide scanable information to a cell phone app.
quick response codes
_____ describes transmissions using frequencies between 50 Hz and 1 THz
radio frequency (RF)
isn't restricted to any specific order when accessing data. Rather, it can access any storage location directly
random access
_______ is the maximum number of bits or bytes per second that the channel can carry
raw data transfer rate
____ measures a channel's theoretical capacity. ____ measures the actual capacity of a channel when a specific communciation protocol is used
raw data transfer rate, effective data transfer rate
A successful read operation requires a magnetic charge above a certain threshold
read threshold
In a magnetic disk drive, a(n) ____________________ is mounted on the end of an access arm for each platter surface.
read/write head
the ______ of a hard disk drive generate or respond to a magenetic field
read/write heads
Threads in the _______ are idle, pending availability of a CPU. Many threads can be in this state at one time
ready state
dispatching a thread moves it from the _____ state to the _____ state
ready, running
A computer's physical devices and associated system software are called ______. the resources that are apparent to a program or user are called ______
real resources, virtual resources
______ guarantees a minimum amount of CPU time to a thread if the thread makes an explicit real-time scheduling request when its created. Guarantees a thread enough resoruces to complete its function.
real-time scheduling
______ scheduling guarantees that a thread receives enough resources to complete one ____ within a maximum time interval
real-time, thread cycle
color video display can be achieved by using elements colored _____, _____ and ______
red, green, blue
dynamic RAM requires frequent _____ to maintain its data content
refresh ccylces
Each transfer of a full screen of data from the display generator to the monitor is called a ______
refresh cycle
The number of refresh cycles per second is normally stated in hertz and called the ______
refresh rate
The drawback of wireless transmission include:
regulatory and legal issues, cost of transmitting and receiving stations, high demand for unused radio frequencies, susceptibility to many forms of external interference security concerns.
A _____ extracts the data embedded in a signal it receives and retransmits a new signal containing the same data
repeater
one or more _____ are used when channel length needs to be longer than S/N ratio would normally allow. These extract the data embedded in a signal it receives and retransmits a new signal containing the same data
repeaters
The_______ of a display is the number of pixels displayed per linear measurement unit. It is typically stated in dots per inch.
resolution
OS ________ are essentially a bridge between users, their processes, and the hardware resources used by these processes.
resource allocation.
All active thread control blocks are organized into a data structure called a ______
run queue or thread list
How do you determine which read thread has been waiting the longest?
run the run queue by waiting time
After it is dispatched, the thread enters the _______ and retains control of a CPU until one of these events: the thread or parent process terminates or an interrupt occurs
running state
The process of converting analog sound waves to digital representation is called_____
sampling
______ is the process of converting analog sound waves to a digital representaion thousands of times per second
sampling
the process of converting analog sound waves to digital representation is called _____
sampling
when a user presses a key, the keyboard controller sends a _____ to the computer
scan code
______ describes the decision-making process the OS uses to determine which ready thread moves to the running state and the OS process that makes scheduling decision is called the ______
scheduling; scheduler
_______ is a fractional portion of a track. Until recently, a sector held 512 bytes.
sector
describes the data transfer unit for magnetic disk and optical disc drives.
sector
time to read two adjacent sectors on the same track and recording surface.
sequential access time
_______ communication send bits one at a time over a single transmisison line or electrical circuit
serial
A ______ storage device stores and retrieves data items in a linear, or sequential, order.
serial access
storage devices stores and retrieves data items in a liner, or sequential order
serial access
transmits all bits one at a time over a single electrical transmission line, optical fiber, or frequency band
serial transmission
three broad classes of access methods are
serial, random, parallel
bare-metal hypervisor is used for applications such as _______ and _______
server consolidation and desktop virtualization
A request to execute a service layer function is called a _____
service call
A request to execute a service-layer function is called a _____
service call
implies a resource request by the thread - thread moves to the blocked state unless the resource can be immediately provided
service call
THe ____ of the OS contains thousands of reusable components that provide functions ranging from file and folder manipulation to accessing I/O devices, starting and stopping programs, and creating, moving, and resizing GUI windows
service layer
The _____ contains thousands of reusable components that provide functions ranging from file and folder manipulation to accessing I/O devices; starting and stopping programs; and creating, moving, and resizing GUI windows.
service layer
The ____ is the user interface to the OS
shell
________ scheduling chooses the next thread to be dispatched based on the expected amount of CPU time needed to complete the process
shortest time remaining (STR)
with the ______ scheduling method, threads requiring the least CPU time are dispatched first
shortest time remaining or STR
wireless networks and cell phones use the upper end of the RF spectrum called _____
shortwave radio
the child processes of a single parent are collectively called _____
sibling processes
a ____ is a data transmission event or group of events representing a bit or group of bits
signal
S/N ratio =
signal power - noise power
A communicaiton channel using electrical signals must have at least two wires- a ______ and a _______ to form a complete electrical circuit
signal wire, return wire
A single electrical communication channel requires two wires: a _______, which carries data, and a ______, which completes an electrical circuit between sending and receiving devices
signal wire, return wire
In _____ mode, messages flow in only one direction
simplex
light, radio frequencies, and electricity travel through space or cables as a _________
sine wave
_____ cable uses fibers that vary continuously in diameter from center to edge
single mode fiber optic
uses smaller diameter optical fibers that vary continuously in density from center to edge
single-mode cable
Resource allocation in a ______ OS involves only two running programs- an application and the OS
single-tasking
The drawbacks of using bitmaps to represent high quality images are _____ and no________ for raw bitmaps. An _______ addresses both drawbacks by storing images compactly. Many, but not all, are device independent.
size and standard storage format, image description language
Because of slight differences in parallel transmission lines, data bits might arrive at the receiver at slightly different times. The timing difference between bits, called _____, increases with distance and transmission rate
skew
the length of a parallel communication channel is limited by _____, which can cause bits to arrive at slightly different times
skew
a _____ mimcs the behavior and physical size of a magnetic disk drive but has no moving parts
solid state drive
is a storage device that mimics the behavior of a magnetic disk drive but uses flash RAM or other NVM devices as the storage medium and read/write mechanism.
solid state drive
differences between solid state and magnetic disk drives Read speeds Write speeds volatility Portability
solid-state faster, solid-state slower (80% of read), magnetic longer life, solid-state more
General-purpose audio hardware can be integrated on a computer or cell phone motherboard or packaged as an expansion card that connects to the system bus (________)
sound card
Processes can create, or ________, other processes and communicate with them
spawn
processes can create or ______, other processes and communicate with them
spawn
• Most current speech-recognition systems are _________ which means theyre trained to recognize the sounds of individual human speakers with acceptable accuracy.
speaker dependent
_____ speech-recognition programs must be trained to recognize one person's voice
speaker-dependent
________ is the process of recognizing and responding to the meaning embedded in spoken words, phrases, or sentences. Human speech consists of a series of sounds called _______, roughly corresponding to the sounds of each letter of the alphabet.
speech recognition, phonemes
A more general and complex approach to speech generation is ________, in which vocal sounds are stored in the system.
speech synthesis
is the most important characteristic differentiating primary and secondary storage
speed
is the most important characteristic differentiating primary and secondary storage.
speed
portability is usually obtained at the expense of ______
speed
digital signals are sent by using _____ waves
square
A _____ can be approximated by combining a series of sine waves. Higher quality approximations require higher banwidth
square wave
Digital signal can be generated by using a _______ instead of a sine wave. This contains abrupt amplitude shifts between two different values
square wave
_______ are the preferred method of transmitting digital data over short distances, such as on a system bus
square waves
in asynchronous transmission, at least one ______ is added to the beginning of each message
start bit
added to the beginning of each message. The ____ wakes up the receiver, informs it that a message is about to arrive, and provides an opportunity for the receiver to synchronize its clock before data bits arrive
start bits
is implemented entirely with transistors. Basic storage unit is a flip-flop circuit.
static RAM (SRAM)
A storage device consists of a read/write mechanism and a storage medium. The ______ is the device or substance that actually holds data. The ______ is the device used to read or write data to and from the storage medium. _______ provides the interface between the storage device and the system bus.
storage medium, read/write mechanism, device controller
The printing industry generally uses inks based on the _____ colors, which are _____, _____ and _______. A _____ ink can also be used as a fourth color
subtractive, cyan, magenta, yellow, black
_________ Transmission ensures that sender and receive clocks are always synchronized by sending continuous data streams
sunchronous
is calculated with much less optimistic assumptions about data location.
sustained data transfer rate
a secondary storage region, called the _____ is reserved for the task of storing pages not held in memory
swap space
memory pages not held in primary storage are held in the _____ of a secondary storage device
swap space
A secondary storage region, called the _____ is reserved for the task of storing pages not held in memory
swap space or swap file or page file
in _______ communication, signals are transmitted continuously, even when theres no data to send, to ensure clock synchronization
synchronous
sender and receiver synchronize the start and duration of each bit value by referencing a common clock signal. describes any means by which sender/receiver keeps both clock parameters the same
synchronous communication
when no data is being transmitted, _______ are sent continuously to prevent clock drift
synchronous idle characters
hardware resources consumed by an OS's resource allocation functions are called _____
system overhead
the resources consumed by OS resource allocation procedures are sometimes referred to as ______
system overhead
the resources consumed by resource allocation procedures are sometimes referred to as ______
system overhead
the advantage of organizing an application program into a family of threads instead of multiple processes is that ______________________
system overhead for resource allocation and process management is reduced.
Tapes are mounted in a ________, which is slow serial access device, for reading and writing.
tape drive
A _____ is an executable subunit of a process that's scheduled independently but shares memory and I/O resources
thread
A ______ is a portion of a process that can be scheduled and executed independently.
thread
A ______ is a portion of a process that can be scheduled and executed independtly
thread
The OS keeps track of thread-specific information in a _______
thread control block
A ______ typically includes instructions to process a single transaction, retrieve and store one data item from an I/O device, or retrieve and analyze one set of factory control data
thread cycle
describes any technique that breaks data transfer capacity into time slices and allocates them to multiple users
time-division multiplexing (TDM)
The CPU periodically generates a ______ to give the scheduler an opportunity to allocate the CPU to another ready process
timer interrupt
is generated at regular intervals of between several dozen and several thousand CPU cycles
timer interrupt
A(n) ____________________ is an LCD or LED display with additional TFT layers that detect the position of electrical field changes based on capacitance.
touchscreen
______ is one concentric circle of a platter, or the surface area
track
a ____ is a series of sectors stored along one concentric circle on a platter
track
the communication path that transports signals is called a _____
transmission medium
5. Because plasma displays actively generate colored light near the display surface, theyre brighter and have a wider viewing angle than LCDs
true
A parallel channel's transmits individual bits over separate wires, fibers, or frequencies
true
A raw data transfer rate is the maximum number of bits or bytes per second that the channel can carry
true
A storage device consists of a read/write mechanism and a storage medium
true
An advantage of optical over mechanical mice is a lack of moving parts that can be contaminated with dust and dirt
true
Analog signals have high transmission capacity and high error rate
true
At a minimum, sound cards include an ADC, a DAC, a low-power amplifier, and connectors (jacks) for a microphone and a speaker or headphones.
true
Both SRAM and DRAM are slower than CPU
true
Color laser output uses four separate print generators
true
Command messages an be used to transmit information about data messages, such as format, content, length, and other information the receiver needs to interpret the data message correctly.
true
Compared to magnetic disk, tapes are more susceptible to problems (leakage, decay, etc.)
true
Cyclic redundancy checking (CRC) is the most widely used error detection method
true
DRAM chip cannot perform a refresh operation at the same time it performs a read or write operation.
true
Data is normally recorded on both sides of a platter
true
Higher resolutions correspond to smaller pixel sizes
true
In an Intel CPU, a page table entry includes the page's physical memory address if its loaded into memory
true
Modern display devices use the additive colors to produce the colors that we see
true
Modern video monitors, often called flat panel displays, use a wide variety of technologies to generate displays.
true
OLED displays combine many of the best features of LCDs and plasma displays.
true
Operating systems are organized internally into layers.
true
Parity checking can be based on even or odd bit counts
true
Phonemes sound similar when voiced repetitively by the same person
true
RAM is fabricated in the same manner as microprocessors.
true
RF transmission is more complex than wired transmission because it incorporates more sophisticated error detection/correction and security methods
true
Read/write and storage medium can be same or different technologies
true
SRAM is volatile
true
The OS creates a PCB when a process is created, updates the PCB as the process status changes, and deletes the PCB when the process terminates
true
The basic unit of display is the pixel
true
Unlike PDF417 bar codes, QR codes are intended to be scanned by an optical scanner, not scanning lasers.
true
a blocked thread is waiting for an event to occur, such as allocation of a requested resource or correction of an error condition
true
a single device can employ multiple access methods
true
analog signal can carry more information than digital signals in a fixed time interval
true
capacitors charge and discharge faster than batteries
true
higher transmission frequency yields higher raw data transfer rate
true
noncontiguous memory allocation is more flexible than contiguous memory allocation, but flexibility comes at a price
true
sequential access time is faster than average access time
true
the amount of voltage produced varies over long distances
true
the nature of a sine wave makes holding phase constant impossible
true
with an Intel CPU, virtual memory management responsibility is split between the CPU and the OS
true
is similar to coaxial cable, except that it contains two internal conductors and is thinner
twin-axial cable.
__________ Cable is the most common transmission medium for phone and local area network (LAN) connections
twisted pair
is the most common transmission medium for wired telephone and local area network connections
twisted-pair wire
the two most common forms of copper wiring used for data communication are bundles of _____ and ______
twisted-pair wire and coaxial cable
_______ also called ______, uses the atmosphere or space to carry messages encoded in radio frequency or light signals
unguided transmission, wireless transmission
A _____ is a line segment with a specific angle and length in relation to a point of origin. Line drawings can be described as a ________, a series of concatenated or linked vectors that can be used to construct complex shapes, such as boxes, triangles, and the inner and outer lines of a table or spreadsheet.
vector, vector list
______ is a flash RAM technology that provides higher capacity than traditional 20/planar flash RAM technology
vertical flash RAM
If all page frames are allocated, a page currently in memory, called the ______, must be written to the swap space before the reference page is loaded into a page frame
victim
A _____ accepts data or commands over the system bus and generates output for a video monitor
video controller
The ________accepts commands and data from the CPU and memory and generates analog or digital video signals, which are transmitted to the monitor.
video controller
Video display panels are connected to a ____ that's connected to a port on the system bus or a dedicated video bus
video controller
______ is connected through dedicated low-speed communication links
video display
A _______ resource is apparent to a process or user, although it might not physically exist
virtual
to achieve efficient use of memory and a large number of concurrently executing processes, most OSs use _____ memory management
virtual
_______ divides a program into partitions called pages
virtual memory management
is an application that installs under a traditional OS and enables VMs to be created and run within it
virtualization environment
the contents of most forms of RAM are ______ making them unsitable for long term data storage
volatile
Primary storage devices must closely match CPU speed and word size to avoid ______
wait states
Frequency dividision multiplexing of optical channels is sometimes called _____
wavelength-division multiplexing
portability is implemented in one of two ways
• The entire storage device- storage medium, read/write mechanism, and possibly controller- can be transported between computer systems • The storage medium can be removed from the storage device and transported to a compatible storage medium on another computer
