sonic anemometer , an infrared gas analyzer and some sensor to hygrometer measure humidity ... ref main Infrared gas analyzer Image Humidity sensor.jpg thumb left An example of a hygrometer This sensor ... the anemometer to get their air sample. ref name Baldocchi2001 main Hygrometer The hygrogemeter is an essential ... more details
Refimprove date January 2007 Expert subject meteorology date November 2008 Image Stevenson screen exterior.JPG thumb Exterior of a Stevenson screen Image Stevenson screen interior.JPG thumb Interior of a Stevenson screen A Stevenson screen or instrument shelter is an enclosure to shield meteorological instruments against precipitation meteorology precipitation and direct heat radiation from outside sources, while still allowing air to circulate freely around them. ref cite web url http www.on.ec.gc.ca skywatchers ontario wx office tour compound screen e.html title Stevenson Screen accessdate 2007 12 04 publisher Environment Canada ref It forms part of a standard weather station . The Stevenson screen holds instruments that may include thermometer s ordinary, maximum minimum thermometer maximum minimum , a hygrometer , a psychrometer, a dewcell , a barometer and a thermograph . Stevenson screens may also be known as a cotton region shelter, an instrument shelter, a thermometer shelter, a thermoscreen or a thermometer screen. Its purpose is to provide a standardised environment in which to measure temperature, humidity, dewpoint and atmospheric pressure. History It was designed by Thomas Stevenson 1818 1887 , a United Kingdom of Great Britain and Ireland British civil engineer and father of the author Robert Louis Stevenson . Composition The traditional Stevenson Screen is a box shape, constructed of wood, in a double louver ed design. However, it is possible to construct a screen using other materials and shapes, such as a pyramid. The World Meteorological Organization WMO agreed standard for the height of the thermometers is between 1.25 m 4 ft 1 in and 2 m 6 ft 7 in above the ground. Size The interior size of the screen will depend on the number of instruments that are to be used. A single screen may measure 765 mm high by 610 mm wide by 593 mm deep 30.1 in by 24.0 in by 23.3 in and a double screen 765 mm high by 1050 mm wide x 59 ... more details
Image IMG 0430 aws rothera 1200x900.jpg thumb right An AWS in Antarctica An automatic weather station AWS is an automated version of the traditional weather station , either to save human labour or to enable measurements from remote areas. ref name AWSs An AWS will typically consist of a weather proof enclosure containing the data logger , rechargeable battery , telemetry optional and the meteorological sensors with an attached Photovoltaic module solar panel or wind turbine and mounted upon a mast. The specific configuration may vary due to the purpose of the system. ref name AWSs cite web url http www.automaticweatherstation.com index.html title Automatic Weather Stations last King first Jeremy accessdate 2009 04 15 ref The system may report in near real time via the Argos System and the Global Telecommunications System , ref name AWSP cite web url http uwamrc.ssec.wisc.edu aboutaws.html title About the Automatic Weather Station project work Automatic Weather Station project publisher The National Science Foundation Office of Polar Programs accessdate 2009 04 15 Dead link date November 2010 bot H3llBot ref or save the data for later recovery. ref name ADDI cite web url http www.aadi.no Aanderaa Products AWS default.aspx title ADDI Automatic weather stations publisher ADDI accessdate 2009 04 15 ref In the past, automatic weather stations were often placed where electricity and communication lines were available. Nowadays, the photovoltaic module solar panel , wind turbine and mobile phone technology have made it possible to have wireless stations that are not connected to the electrical grid or telecommunications network. ref name ABM Sensors Most automatic weather stations have ref name AWSs ref name NHW cite web url http www.northantsweather.org.uk weathertour aws.htm title North Hants Weather AWS accessdate 2009 04 15 ref Thermometer for measuring temperature Anemometer for measuring wind speed Wind vane for measuring wind direction Hygrometer for measuring humi ... more details
Arjen Roelofs 1 March 1754, Hijum 11 May 1828, Hijum was a Netherlands Dutch astronomer . Early life Roelofs was born on the Hommema sate estate near Hijum in Friesland , as the youngest of four sons and two daughters. His father was Roelof Pytters, a tenant farmer and tax receiver. His mother was Neeltje Alberts from Finkum. The oldest son Klaas trained as a steersman, but did not work as one, and instead became a doctor in Sexbierum . The other sister Lisbeth married and left the household. It was not an easy life on the farm, but this is where the other three boys, Pieter, Albert and Arjen had to work. Their mother stimulated the interest of the three sons in mathematics and science , however their father was unhappy with this. After their parents had died in 1790, the three brothers took over the farm, and their sister Antje became their housekeeper. None of these four ever married, and they all lived on the farm until they died. Arjen Roelofs was supposed to have had polio so he could not use his right leg very well, and later he could not work on the farm anymore. This enabled him to spend more time on his hobbies. Also his brothers joined him in his hobbies. Pieter was known as a mathematician , but was also an excellent instrument maker . Arjen designed telescope s, and Pieter made them. Albert was a clockmaker . Pieter and Arjen took meteorological measurements and made instruments to accomplish this. They made thermometer s, hygrometer s, and measured wind speed and wind direction . Circle of friends Eise Eisinga regularly spent time at Hijum. He ensured that University of Franeker professor Johan Henri van Swinden became a very regular visitor. Roelofs also took on students. His cousin Roel Hessels Hommema, and his friend Rinse Bearts Gelder were taught in Hijum. Later Arjen regularly worked with instrument maker and farmer Sieds Johannes Rienks of Hallum . In 1817 they presented a plan for the construction of a telescope to the Dutch Government. The plan ... more details
sur l hygrom trie , published in 1783, he records experiments made with various forms of hygrometer in all climates and at all temperatures, and supports the claims of his hair hygrometer against ... more details
glossary search?id mixing ratio1 ref Measurement Image Umidaderelativa.jpg thumb A hygrometer ... humidity is called a psychrometer or hygrometer . A humidistat is used to regulate the relative ... Dew point Dew point depression Humidity indicator Hygrometer Psychrometrics References Reflist ... more details
Image Humidor Vorbereitung.jpg thumb right A humidor is being prepared for use. Image Elie Bleu Medailles.JPG thumb An Elie Bleu Medaille in blue. A humidor is any kind of box or room with constant humidity , used to store cigar s, cigarette s, or smoking pipe tobacco pipe tobacco. For private use, small wooden or acrylic glass humidor boxes for a few dozen cigars are used, while cigar shops may have walk in humidors, sometimes consisting of a whole floor. Humidors can be used to store other goods for which a certain level of humidity is desirable the Colorado Rockies Major League Baseball team stores baseball ball game balls in a large humidor at their home stadium, Coors Field , to counteract the effects of Denver s high altitude and generally low humidity. Humidors of all sizes use hygrometer s to keep track of the humidity levels. Classification of humidors Room humidor Most common in cigar bars or stores. One room is built as or converted to a humidor where all the cigars are stored. Cabinet humidor Usually placed on the floor as a piece of furniture. Typically holds 1000 5000 cigars. Table humidor Often quite heavy, though portable in theory, it s usually kept in one location. Capacity ranges from three hundred to a few thousand cigars. It usually comes with a polished wood exterior, marble, leather or combination of exotic elements, and glass top. Personal humidor Semi regular cigar smokers will sometimes keep a small humidor in their homes for personal storage, special events, or aesthetic characteristics of the humidor itself . Usually contains 20 75 cigars. This may also be known as a Desktop Humidor . Citation needed date January 2009 Travel humidor Portable and made for carrying cigars enough for the outing or event. Usual counts supported are 2 to 10 cigars. Construction Commercially made humidor cases are typically made of woodboard, although other materials, like acrylic glass and metal, are not uncommon. Carbon fibre , silicon carbide , and polyethyl ... more details
About other uses of the root word meteor Meteor disambiguation about data mining Data mining Meteorology is the interdisciplinary scientific study of the atmosphere . It observes the changes in temperature, air pressure, moisture and wind direction. Usually, temperature, pressure, wind measurements and humidity are the variables that are measured by a thermometer, barometer, anemometer, and hygrometer, respectively. There are many methods of collecting data and Radar , Lidar , satellites are some of them. Weather forecasts are made by collecting quantitative data about the current state of the atmosphere. The main issue arise in this prediction is, it involves high dimensional characters. To overcome this issue, it is necessary to first analyze and simplify the data before proceeding with other analysis. Some data mining techniques are appropriate in this context. What is Data mining? Data mining , the extraction of hidden predictive information from large databases, is a powerful new technology with great potential to analyze important information in data warehouses. Consequently, data mining consists of more than collecting and analyzing data, it also includes analyze and predictions. The tools which are use to analysis can include statistical models , mathematical algorithms and machine learning methods. These methods include algorithms that improve their performance automatically through experience, such as neural networks or decision trees ref cite news author Seifert, W. title Data Mining An Overview journal CRS year 2004 ref The network architecture and signal process used to model nervous systems can roughly be divided into three categories, each based on a different philosophy. Feedforward neural network the input information defines the initial signals into set of output signals. ref cite news author Kohonen, T. 2002 . title The Self Organizing Map. journal IEEE pages 1464 1480. ref Feedback network the input information defines the initial activity state ... more details
distinguish Hygrometer File Hydrometer6455.png thumb upright Hydrometer from Practical Physics File Aerometer.svg thumb upright Schematic drawing of a hydrometer. The lower the density of the fluid, the deeper the weighted float B will sink the depth can be read off the scale A. A hydrometer is an instrument used to measure the specific gravity or relative density of liquids that is, the ratio of the density of the liquid to the density of water. A hydrometer is usually made of glass and consists of a cylindrical stem and a bulb weighted with mercury element mercury or lead shot to make it float upright. The liquid to be tested is poured into a tall container, often a graduated cylinder , and the hydrometer is gently lowered into the liquid until it floats freely. The point at which the surface of the liquid touches the stem of the hydrometer is noted. Hydrometers usually contain a scale inside the stem, so that the specific gravity can be read directly. A variety of scales exist, and are used depending on the context. Hydrometers may be calibrated for different uses, such as a lactometer for measuring the density creaminess of milk, a saccharometer for measuring the density of sugar in a liquid, or an alcoholometer for measuring higher levels of alcohol in Distilled beverage spirits . Principle Operation of the hydrometer is based on Buoyancy Archimedes principle that a solid suspended in a fluid will be buoyed up by a force equal to the weight of the fluid displaced by the submerged part of the suspended solid. Thus, the lower the density of the substance, the farther the hydrometer will sink. See also Relative density Relative density and hydrometers Relative density and hydrometers . History An early description of a hydrometer appears in a letter from Synesius of Cyrene to the Greek scholar Hypatia of Alexandria . In Synesius fifteenth letter, he requests Hypatia to make a hydrometer for him. Hypatia is given credit for inventing the hydrometer or hydroscope sometime ... more details
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