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Clothing Insulation
Clothing insulation is the thermal insulation provided by clothing.ANSI/ASHRAE Standard 55-2010, Thermal Environmental Conditions for Human Occupancy Even if the main role of clothing is to protect from the cold, protective clothing also exists to protect from heat, such as for metallurgical workers or firemen. As regards thermal comfort, only the first case is considered. Thermophysiological comfort Thermophysiological comfort is the capacity of the clothing material that makes the balance of moisture and heat between the body and the environment. It is a property of textile materials that creates ease by maintaining moisture and thermal levels in a human's resting and active states. The selection of textile material significantly affects the comfort of the wearer. Different textile fiber holds individual properties that suit in different environments. Natural fibers are breathable and absorb moisture, while synthetic fibers are hydrophobic; they repel moisture and do not allow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Insulation
Thermal insulation is the reduction of heat transfer (i.e., the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials. Heat flow is an inevitable consequence of contact between objects of different temperature. Thermal insulation provides a region of insulation in which thermal conduction is reduced, creating a thermal break or thermal barrier, or thermal radiation is reflected rather than absorbed by the lower-temperature body. The insulating capability of a material is measured as the inverse of thermal conductivity, thermal conductivity (k). Low thermal conductivity is equivalent to high insulating capability (R-value (insulation), resistance value). In thermal engineering, other important properties of insulating materials are product density, density (ρ) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelvin
The kelvin (symbol: K) is the base unit for temperature in the International System of Units (SI). The Kelvin scale is an absolute temperature scale that starts at the lowest possible temperature (absolute zero), taken to be 0 K. By definition, the Celsius scale (symbol °C) and the Kelvin scale have the exact same magnitude; that is, a rise of 1 K is equal to a rise of 1 °C and vice versa, and any temperature in degrees Celsius can be converted to kelvin by adding 273.15. The 19th century British scientist Lord Kelvin first developed and proposed the scale. It was often called the "absolute Celsius" scale in the early 20th century. The kelvin was formally added to the International System of Units in 1954, defining 273.16 K to be the triple point of water. The Celsius, Fahrenheit, and Rankine scales were redefined in terms of the Kelvin scale using this definition. The 2019 revision of the SI now defines the kelvin in terms of energy by setting the Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Insulance
The ''R''-value is a measure of how well a two-dimensional barrier, such as a layer of insulation, a window or a complete wall or ceiling, resists the conductive flow of heat, in the context of construction. R-value is the temperature difference per unit of heat flux needed to sustain one unit of heat flux between the warmer surface and colder surface of a barrier under steady-state conditions. The measure is therefore equally relevant for lowering energy bills for heating in the winter, for cooling in the summer, and for general comfort. The ''R-value'' is the building industry term for thermal resistance "per unit area." It is sometimes denoted RSI-value if the SI units are used. An R-value can be given for a material (e.g., for polyethylene foam), or for an assembly of materials (e.g., a wall or a window). In the case of materials, it is often expressed in terms of R-value per metre. R-values are additive for layers of materials, and the higher the R-value the better th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duvet
A duvet ( , ; ), usually called a comforter or (''down-filled'') quilt in American English, and a doona in Australian English, is a type of bedding consisting of a soft flat bag filled with down feather, down, feathers, wool, cotton, silk, or a synthetic alternative, and is typically protected with a removable duvet cover, cover, similar to a pillow and pillow case. The term ''duvet'' is mainly British, especially in reference to the bedding; rarely used in US English, it often refers to the cover. Sleepers often use a duvet without a top bed sheet, as the duvet cover can readily be removed and laundered as often as the bottom sheet. Duvets (known there as eiderdowns, in translation) originated in rural Europe and were filled with the down feathers of ducks or geese. The best quality feathers are taken from the Eider, eider duck, which is known for its effectiveness as a Thermal insulation, thermal insulator. Prior to the uptake of the duvet as a popular bedding option in Bri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Down Feather
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down. Powder down is a specialized type of down found only in a few groups of birds. Down is a fine thermal insulator and padding, used in goods such as Down jacket, jackets, bedding (duvets and featherbeds), pillows and sleeping bags. The discovery of feathers trapped in ancient amber suggests that some species of non-avian dinosaur likely possessed down-like feathers. Description and etymology The word ''down'' comes from the Old Norse word ''dúnn'', which had the same meaning as its modern equivalent. The down feather is considered to be the most "straightforward" of all feather types. It has a short or vestigial rachis (shaft), few barb (feather), barbs, and barbules that lack hooks. There are three types of down: natal down, body down and powder down. Natal down is the layer of down feathers that cover most birds at some point in their early developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornell University
Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson White in 1865. Since its founding, Cornell University has been a Mixed-sex education, co-educational and nonsectarian institution. As of fall 2024, the student body included 16,128 undergraduate and 10,665 graduate students from all 50 U.S. states and 130 countries. The university is organized into eight Undergraduate education, undergraduate colleges and seven Postgraduate education, graduate divisions on its main Ithaca campus. Each college and academic division has near autonomy in defining its respective admission standards and academic curriculum. In addition to its primary campus in Ithaca, Cornell University administers three satellite campuses, including two in New York City, the Weill Cornell Medicine, medical school and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tog (unit)
The tog is a measure of thermal insulance of a unit area, also known as thermal resistance. It is commonly used in the textile industry and often seen quoted on household items such as duvets, sleeping bags and carpet underlay. Origin F. T. Peirce and W. H. Rees, of the Shirley Institute in Manchester, England, developed the tog in 1946 as more convenient alternative to the SI unit m2⋅K/W, writing in their paper ''The Transmission of Heat Through Textile Fabrics – part II'': The results given in this paper are expressed in terms of watts, °C and metres. So that practical clothing may be described conveniently by a range of small integers, the unit of thermal resistance, to be called the “tog”, is the resistance that will maintain a temperature difference of 0.1 °C. with a flux of 1 watt per square metre, or in more practical terms, 10 °C. with a flux of 1 watt per square decimetre.Peirce and Rees do not give any explanation in their paper for their ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clothing Ensembles And Garments
Clothing (also known as clothes, garments, dress, apparel, or attire) is any item worn on a human human body, body. Typically, clothing is made of fabrics or textiles, but over time it has included garments made from animal skin and other thin sheets of materials and natural products found in the environment, put together. The wearing of clothing is mostly restricted to human beings and is a feature of all human societies. The amount and type of clothing worn depends on gender, body type, social factors, and geographic considerations. Garments cover the body, footwear covers the feet, gloves cover the hands, while hats and headgear cover the head, and underwear covers the intimate parts. Clothing serves many purposes: it can serve as protection from the elements, rough surfaces, sharp stones, rash-causing plants, and insect bites, by providing a barrier between the skin and the environment. Clothing can insulate against cold or hot conditions, and it can provide a hygienic barrie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Manikin
The thermal manikin is a human model designed for scientific testing of thermal environments without the risk or inaccuracies inherent in human subject testing. Thermal manikins are primarily used in automotive, Building science, indoor environment, outdoor environment, military and clothing research. The first thermal manikins in the 1940s were developed by the US Army and consisted of one whole-body sampling zone. Modern-day manikins can have over 30 individually controlled zones. Each zone (right hand, pelvis, etc.) contains a heating element and temperature sensors within the “skin” of the manikin. This allows the control software to heat the manikin to a normal human body temperature, while logging the amount of power necessary to do so in each zone and the temperature of that zone. History Clothing insulation is the thermal insulation provided by clothing and it is measured in clo. The measuring unit was developed in 1941. Shortly afterward, thermal manikins were develope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hour
An hour (symbol: h; also abbreviated hr) is a unit of time historically reckoned as of a day and defined contemporarily as exactly 3,600 seconds ( SI). There are 60 minutes in an hour, and 24 hours in a day. The hour was initially established in the ancient Near East as a variable measure of of the night or daytime. Such seasonal hours, also known as temporal hours or unequal hours, varied by season and latitude. Equal hours or equinoctial hours were taken as of the day as measured from noon to noon; the minor seasonal variations of this unit were eventually smoothed by making it of the mean solar day. Since this unit was not constant due to long term variations in the Earth's rotation, the hour was finally separated from the Earth's rotation and defined in terms of the atomic or physical second. It is a non-SI unit that is accepted for use with SI. In the modern metric system, one hour is defined as 3,600 atomic seconds. However, on rare occasions an hour may inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fahrenheit
The Fahrenheit scale () is a scale of temperature, temperature scale based on one proposed in 1724 by the German-Polish physicist Daniel Gabriel Fahrenheit (1686–1736). It uses the degree Fahrenheit (symbol: °F) as the unit. Several accounts of how he originally defined his scale exist, but the original paper suggests the lower defining point, 0 °F, was established as the freezing temperature of a solution of brine made from a mixture of water, ice, and ammonium chloride (a Salt (chemistry), salt). The other limit established was his best estimate of the average human body temperature, originally set at 90 °F, then 96 °F (about 2.6 °F less than the modern value due to a later redefinition of the scale). For much of the 20th century, the Fahrenheit scale was defined by two fixed points with a 180 °F separation: the temperature at which pure water freezes was defined as 32 °F and the boiling point of water was defined to be 212 °F, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foot (length)
The foot (standard symbol: ft) is a unit of length in the British imperial and United States customary systems of measurement. The prime symbol, , is commonly used to represent the foot. In both customary and imperial units, one foot comprises 12 inches, and one yard comprises three feet. Since an international agreement in 1959, the foot is defined as equal to exactly 0.3048 meters. Historically, the "foot" was a part of many local systems of units, including the Greek, Roman, Chinese, French, and English systems. It varied in length from country to country, from city to city, and sometimes from trade to trade. Its length was usually between 250 mm and 335 mm and was generally, but not always, subdivided into 12 inches or 16 digits. The United States is the only industrialized country that uses the (international) foot in preference to the meter in its commercial, engineering, and standards activities. The foot is legally recognized in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
