Signal-to-noise ratio is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to the noise power expressed in decibels. A ratio higher than 1:1 indicates more signal than noise. While SNR is quoted for electrical signals, it can be applied to any form of signal, for example isotope levels in an ice core, biochemical signaling between cells, or financial trading signals. Signal-to-noise ratio is sometimes used metaphorically to refer to the ratio of useful information to false or irrelevant data in a conversation or exchange. For example, in online discussion forums and other online communities, off-topic posts and spam are regarded as "noise" that interferes with the "signal" of appropriate discussion; the signal-to-noise ratio, the bandwidth, the channel capacity of a communication channel are connected by the Shannon–Hartley theorem. Signal-to-noise ratio is defined as the ratio of the power of a signal to the power of background noise: S N R = P s i g n a l P n o i s e, where P is average power.
Both signal and noise power must be measured at the same or equivalent points in a system, within the same system bandwidth. Depending on whether the signal is a constant or a random variable, the signal-to-noise ratio for random noise N becomes: S N R = s 2 E where E refers to the expected value, i.e. in this case the mean square of N, or S N R = E E If the noise has expected value of zero, as is common, the denominator is its variance, the square of its standard deviation σN. The signal and the noise must be measured the same way, for example as voltages across the same impedance; the root mean squares can alternatively be used in the ratio: S N R = P s i g n a l P n o i s e = 2, where A is root mean square amplitude. Because many signals have a wide dynamic range, signals are expressed using the logarithmic decibel scale. Based upon the definition of decibel and noise may be expressed in decibels as P s i g n a l, d B = 10 log 10 and P n o i s e, d B = 10 log 10 . In a similar manner, SNR may be expressed in decibels as S N R d B = 10 log 10 .
Using the definition of SNR S N R d B = 10 log 10 . Using the quotient rule for logarithms 10 log 10 ( P s i g n a l
Song of Spring is a 1950 Italian melodrama film directed by Mario Costa and starring Leonardo Cortese, Delia Scala and Tamara Lees. The film's sets were designed by Alberto Boccianti. Leonardo Cortese as Mario Delia Scala as Rosetta Tamara Lees as Evi Claudio Villa as Himself Laura Gore as Maria Aroldo Tieri as Nino Ludmilla Dudarova as Elena Checco Durante as Pippo Dante Maggio as Gigetto Paola Borboni as Lidia Arturo Bragaglia Piero Lulli as Ugo Enrico Glori Franco Pesce Jone Morino as Fanny Felice Romano Giuseppe Pierozzi Aldo Silvani Vittorio Sanipoli as Max Pasquale Sorrenti. Il cinema e la Puglia. Schena, 1984. Song of Spring on IMDb
Tafers is a municipality in the district of Sense in the canton of Fribourg in Switzerland. It is one of the municipalities with a large majority of German speakers in the French speaking Canton of Fribourg. Tafers has an area of 8.42 km2. Of this area, 5.33 km2 or 63.5% is used for agricultural purposes, while 1.78 km2 or 21.2% is forested. Of the rest of the land, 1.25 km2 or 14.9% is settled and 0.01 km2 or 0.1% is unproductive land. Of the built up area, industrial buildings made up 1.8% of the total area while housing and buildings made up 9.2% and transportation infrastructure made up 3.1%. Out of the forested land, all of the forested land area is covered with heavy forests. Of the agricultural land, 40.0% is used for growing crops and 22.6% is pastures. The blazon of the municipal coat of arms is Gules, a Guard statant afrontee clad Azure and Sable ensigned with a Cross on sinister, holding in dexter a Halberd Argent. Tafers has a population of 3,450; as of 2008, 10.8% of the population are resident foreign nationals.
Over the last 10 years the population has changed at a rate of 4.9%. Migration accounted for 7.8%, while births and deaths accounted for 2.4%. Most of the population speaks German as their first language, French is the second most common and Serbo-Croatian is the third. There are 1 person who speaks Romansh; as of 2008, the population was 51.0 % female. The population was made up of 154 non-Swiss men. There were 151 non-Swiss women. Of the population in the municipality, 847 or about 32.2% were born in Tafers and lived there in 2000. There were 1,089 or 41.5% who were born in the same canton, while 315 or 12.0% were born somewhere else in Switzerland, 279 or 10.6% were born outside of Switzerland. As of 2000, children and teenagers make up 23.2% of the population, while adults make up 60.6% and seniors make up 16.2%. As of 2000, there were 1,099 people who were single and never married in the municipality. There were 1,274 married individuals, 177 widows or widowers and 77 individuals who are divorced.
As of 2000, there were 959 private households in the municipality, an average of 2.5 persons per household. There were 226 households that consist of only one person and 75 households with five or more people. In 2000, a total of 929 apartments were permanently occupied, while 39 apartments were seasonally occupied and 13 apartments were empty; as of 2009, the construction rate of new housing units was 20.4 new units per 1000 residents. The vacancy rate for the municipality, in 2010, was 5.18%. The historical population is given in the following chart: The Parish Church of St. Martin and the Sigristen House are listed as Swiss heritage site of national significance. In the 2011 federal election the most popular party was the CVP; the next three most popular parties were the SVP, the SPS and the CSP. The CVP received about the same percentage of the vote; the SVP moved from third in 2007 to second in 2011, the SPS moved from fourth in 2007 to third and the CSP moved from second in 2007 to fourth.
A total of 1,249 votes were cast in this election, of which 0.9 % were invalid. As of 2010, Tafers had an unemployment rate of 2.1%. As of 2008, there were 66 people employed in the primary economic sector and about 25 businesses involved in this sector. 301 people were employed in the secondary sector and there were 23 businesses in this sector. 1,047 people were employed in the tertiary sector, with 89 businesses in this sector. There were 1,372 residents of the municipality who were employed in some capacity, of which females made up 42.8% of the workforce. In 2008 the total number of full-time equivalent jobs was 1,110; the number of jobs in the primary sector was 43, all of which were in agriculture. The number of jobs in the secondary sector was 280 of which 156 or were in manufacturing and 67 were in construction; the number of jobs in the tertiary sector was 787. In the tertiary sector. In 2000, there were 1,053 workers who commuted into the municipality and 870 workers who commuted away.
The municipality is a net importer of workers, with about 1.2 workers entering the municipality for every one leaving. Of the working population, 13.8% used public transportation to get to work, 60.9% used a private car. From the 2000 census, 2,041 or 77.7% were Roman Catholic, while 276 or 10.5% belonged to the Swiss Reformed Church. Of the rest of the population, there were 47 members of an Orthodox church, there were 2 individuals who belonged to the Christian Catholic Church, there were 44 individuals who belonged to another Christian church. There was 1 individual, Jewish, 72 who were Islamic. There were 10 individuals who were 2 individuals who belonged to another church. 76 (or about
Kalamunda National Park is a national park in Western Australia, 23 kilometres east of Perth, near the town of Kalamunda. The park is composed of typical Darling Scarp woodland including species of marri and wandoo with a diverse understorey including a range of wildflowers. Piesse Brook flows through the park before joining the Helena River, making the park and important catchment area for both the Helena and the Swan Rivers. No fees apply to enter the park but facilities exist within the park for visitors apart from several walk trails including the northern end of the Bibbulmun Track; the park lies within the Mundaring-Kalamunda Important Bird Area, so identified by BirdLife International because of its importance as a non-breeding season roost site and foraging base for long-billed black cockatoos. Protected areas of Western Australia
The Tobler hyperelliptical projection is a family of equal-area pseudocylindrical projections that may be used for world maps. Waldo R. Tobler introduced the construction in 1973 as the hyperelliptical projection, now known as the Tobler hyperelliptical projection; as with any pseudocylindrical projection, in the projection’s normal aspect, the parallels of latitude are parallel, straight lines. Their spacing is calculated to provide the equal-area property; the projection blends the cylindrical equal-area projection with meridians of longitude that follow a particular kind of curve known as superellipses or Lamé curves or sometimes as hyperellipses. The curve is described by xk + yk = γk; the relative weight of the cylindrical equal-area projection is given as α, ranging from all cylindrical equal-area with α = 1 to all hyperellipses with α = 0. When α = 0 and k = 1 the projection degenerates to the Collignon projection. Tobler favored the parameterization shown with the top illustration. List of map projections
Toshitada Doi is a Japanese electrical engineer, who played a significant role in the digital audio revolution. He received a degree in electrical engineering from the Tokyo Institute of Technology in 1964, a PhD from Tohoku University in 1972, he started the first digital audio project within Sony. He was the driving force behind the PCM adaptor, was a prominent member of the Sony/Philips taskforce responsible for the design of the Compact Disc, he created, among the CIRC error correction system. He, with Kees Immink, refutes the myth that the Compact Disc's playing time was determined by Beethoven's Ninth Symphony, he was the lead engineer of the DASH multi-track digital audio tape recorder. In the 1990s, he headed Sony's Digital Creatures Laboratory, where he was responsible for the Aibo, Sony's robotic dog. In 2003, Doi created the a running humanoid robot. Fellowship, Audio Engineering Society Eduard Rhein Prize, 1981 Silver Medal, Audio Engineering Society Toshitada Doi, Machine learning luminary - and AIBO's first master Four Qrio’s perform various dance numbers