Signal processingSignal processing is an electrical engineering subfield that focuses on analyzing, modifying and synthesizing signals, such as sound, , potential fields, seismic signals, altimetry processing, and scientific measurements. Signal processing techniques are used to optimize transmissions, digital storage efficiency, correcting distorted signals, subjective video quality and to also detect or pinpoint components of interest in a measured signal. According to Alan V. Oppenheim and Ronald W.
Detection theoryDetection theory or signal detection theory is a means to measure the ability to differentiate between information-bearing patterns (called stimulus in living organisms, signal in machines) and random patterns that distract from the information (called noise, consisting of background stimuli and random activity of the detection machine and of the nervous system of the operator). In the field of electronics, signal recovery is the separation of such patterns from a disguising background.
ShoeA shoe is an item of footwear intended to protect and comfort the human foot. Though the human foot can adapt to varied terrains and climate conditions, it is vulnerable, and shoes provide protection. Form was originally tied to function but over time shoes also became fashion items. Some shoes are worn as safety equipment, such as steel-toe boots, which are required footwear at industrial worksites. Additionally, fashion has often evolved into many different designs, such as high heels, which are most commonly worn by women during fancy occasions.
String vibrationA vibration in a string is a wave. Resonance causes a vibrating string to produce a sound with constant frequency, i.e. constant pitch. If the length or tension of the string is correctly adjusted, the sound produced is a musical tone. Vibrating strings are the basis of string instruments such as guitars, cellos, and pianos. The velocity of propagation of a wave in a string () is proportional to the square root of the force of tension of the string () and inversely proportional to the square root of the linear density () of the string: This relationship was discovered by Vincenzo Galilei in the late 1500s.
Pointe shoeA pointe shoe (UKpwæ̃t, USpwɑːnt,_pɔːɪnt), also called a ballet shoe, is a type of shoe worn by ballet dancers when performing pointe work. Pointe shoes were conceived in response to the desire for dancers to appear weightless and sylph-like and have evolved to enable dancers to dance en pointe (on the tips of their toes) for extended periods of time. They are manufactured in a variety of colors, most commonly in shades of light pink. Women began to dance ballet in 1681, twenty years after King Louis XIV of France ordered the founding of the Académie Royale de Danse.
Hearing protection fit-testingHearing protector fit-testing, also known as field attenuation estimation system (FAES), measures the degree of noise attenuation when using the hearing protection device by a particular worker in the enterprise. Such measurements are necessary because noise attenuation is very variable among workers, and it can be close to zero for a significant proportion of them. Individual anatomical differences and varying ability to correctly apply HPD do not allow predicting noise attenuation in workers based on laboratory measurements with satisfactory accuracy.
DoorA door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fits into the doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.
High-heeled shoeHigh-heeled shoes, also known as high heels, are a type of shoe with an upward-angled sole. The heel in such shoes is raised above the ball of the foot. High heels cause the legs to appear longer, make the wearer appear taller, accentuating the calf muscle. There are many types of high heels in varying colors, materials, styles, and heights. High heels have been used in various ways to communicate nationality, professional affiliation, gender, and social status.
