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Fitzroy High School | Notable alumni | Notable alumni
Filmmaker Nadia Tass
Invincibles Test Cricketer Neil Harvey
Architect/developer Nonda Katsalidis
Cinematographer/director Vincent Monton
Actor George Spartels
Politician Lidia Thorpe (Years 7 and 9) |
Fitzroy High School | Teachers | Teachers
Writer Helen Garner, former MP Caroline Hogg, former Lord Mayor of Melbourne John So, painter John Brack, and past director of the National Gallery of Australia James Mollison previously taught at the school. |
Fitzroy High School | References | References |
Fitzroy High School | External links | External links
Fitzroy High School
Education Minister's media release
The Age: report of opening
Category:Educational institutions established in 1915
Category:Public high schools in Melbourne
Category:1915 establishments in Australia
Category:Fitzroy, Victoria |
Fitzroy High School | Table of Content | More citations needed, History, Closure, Twelve years later, Fitzroy High reopens its doors, Re-opening, New campus, Notable alumni, Teachers, References, External links |
Stepping switch | short description | In electrical engineering, a stepping switch or stepping relay, also known as a uniselector, is an electromechanical device that switches an input signal path to one of several possible output paths, directed by a train of electrical pulses.
The major use of stepping switches was in early automatic telephone exchanges to route telephone calls. Later, they were often used in industrial control systems. During World War II, Japanese cypher machines, known in the United States as CORAL, JADE, and PURPLE, contained them. Code breakers at Bletchley Park employed uniselectors driven by a continuously rotating motor rather than a series of pulses in the Colossus to cryptanalyse the German Lorenz ciphers.
In a uniselector, the stepping switch steps only along or around one axis, although several sets of contacts are often operated simultaneously. In other types, such as the Strowger switch, invented by Almon Brown Strowger in 1888, mechanical switching occurs in two directions, across a grid of contacts. |
Stepping switch | Single-axis stepping switches | Single-axis stepping switches
thumb|350px|An example of a Western Electric 7A Rotary (Bird-cage) Line Finder assembly. The horizontal shaft is driven by a gear and when the Line Finder's electromagnet is energized, a flexible disc at the base of the Line Finder's brush carriage is engaged through friction to the horizontal shaft's driving disc, causing the brush carriage to rotate.
Stepping switches were widely used in telephony and industrial control systems when electromechanical technology was paramount.
A basic stepping switch is an electrically operated rotary switch with a single (typically input) terminal, and multiple (typically output) terminals. Like other typical rotary switches, the single terminal connects to one of the multiple terminals by rotating a contact arm, sometimes called a wiper, to the desired position. Moving from one position to the next is called stepping, hence the name of the mechanism. Using traditional terminology, this is a single-pole, multi-position switch.
While some stepping switches have only one pole (layer of contacts), a typical switch has more; in the latter case, all wipers are aligned and move together. Hence, one input with multiple wires could be connected to one of multiple outputs, based on the receipt of a single set of pulses. In this configuration, the rotating contacts resembled the head support arms in a modern hard disk drive. Multipole switches were common; some had perhaps as many as a dozen poles, but those were less common.
Most switches have a bank of stationary contacts extending over half a cylinder, while some have only a third of a cylinder. The typical "half-cylinder" switch has two sets of wiper contacts opposite each other, while the "third of a cylinder" type has three sets, equally spaced. For any given level, both or all three wipers are connected, so it makes no difference which of the two (or three) is connecting. When access to more outlets was required, the rotor had two sets of wipers opposite each other but offset vertically: on the first half rotation one set of outlets was accessed; the second set of outlets was accessed on the second half rotation.
An electromagnet advances (steps) the wipers to the next position when fed with a pulse of DC. The magnet's armature (spring-loaded) operates a pawl that advances a ratchet. When the pawl reaches its full stroke, it blocks the ratchet so it and the wipers will not overshoot. When power to the coil disconnects, the spring retracts the pawl. Another pawl, sometimes called a detent spring, pivoted on the frame ensures that the wipers do not move backward; contact friction keeps them in place. Some uniselector designs step on application of the operate pulse; others step on its removal.
thumb|alt=An array of stepping switches|An array of uniselector stepping switches as installed in a telephone exchange. The silver dials show the current position of the moving wipers. The fixed feeder brushes are barely visible.
In most applications, such as telephony, it is desirable to be able to return the wipers to a "home" position; this is at the beginning of rotation, at one end of the array of fixed contacts. Some switches have a cam attached to the wiper shaft. This cam operates a set of contacts when the wiper is at home position, which is at the beginning of the span of rotation. Other circuit designs used one level (pole) of the contacts to home the wipers, so the separate homing contacts were not needed.
Typical stepping switches have contacts directly operated by the stepping magnet's armature; these contacts can serve to make the magnet cycle ("self-step") and advance the wipers as long as power is applied. The external control circuits remove power when the wipers reach the desired position; that could be the home position.
Most stepping switches rotate the wipers in only one direction, but some are bidirectional; the latter have a second magnet to rotate the wipers the other way. A third variety "winds" a spring as the wiper steps progressively, and a ratchet holds the wipers from returning to home position. When the circuit is no longer needed, another electromagnet releases the holding pawl; the spring then returns the wipers to their home position.
Stepping switches were quite noisy in operation (especially when self-stepping), because their mechanisms accelerated and stopped quickly to minimize operating time. One could compare their sound to that of some snap-action mechanisms. Nevertheless, they were engineered for long life, given periodic maintenance; they were quite reliable.
Single-axis stepping switches are sometimes known as uniselectors. |
Stepping switch | Two-axis stepping switch | Two-axis stepping switch
Slightly more complicated was the two axis stepping switch, (also called Strowger switch or two motion selector in Britain). Typically, a single compact group of wipers could connect to one of 100 (or 200) different fixed contacts, in ten levels. When the switch was idle, the wipers were disengaged from the fixed contacts. The wipers moved up and down on a vertical shaft, and rotated into the contact bank to make a connection. A spring, internal to the vertical shaft, returned the wipers to their home position at the bottom.
This type had two stepping coils with pawls and ratchets, one to raise the wipers to the desired banks of contacts, and one to rotate the wipers into the banks. These were commonly used in telephone switching with ten banks of ten contacts. The coils were typically driven by the electrical pulses derived from a rotary telephone dial. On a two-motion selector, as a digit was dialed, the wipers would step up the banks, then automatically rotate (self-step) into the selected bank until they found an "unused" outlet to the next switch stage. The last two digits dialed would operate the connector switch (final selector in Britain). The second to last digit would cause the wipers to move up and the last digit would cause them to rotate into the bank to the called customer's line outlet. If the line was idle then ringing voltage would be applied to the called line and ringing tone was sent to the calling line.
Another variant of the two-axis switch was the Stromberg-Carlson X-Y Switch which was quite common in telephone exchanges in the western USA. It was a flat mechanism, and the moving contacts moved both sidewise, as well as to and fro. It was quite reliable, and could be maintained by people with minimal training. |
Stepping switch | Applications | Applications
Stepping switches are used in a variety of applications, other than telephone systems. By connecting several in series with the highest output of one going to the stepping contact of the next, a counter could be constructed. Or by feeding the stepping contact with an endless pulse train via a relay, and controlling the relay from the switch's own output, it can be made to automatically hunt for the first unpowered line (or powered, depending on whether the relay is normally open or normally closed). They could also be used as a demultiplexer, so that two input lines could control a number of output devices. One input line steps the switch until the correct device is selected, and the other then powers that device. Many other applications are possible.
Such switches were used in a series of Japanese cypher machines during World War 2: CORAL, JADE, PURPLE (the names were American). The British code-breaking machine called Colossus used rotary stepping switches, which was used to break the German Lorenz cipher. |
Stepping switch | References | References |
Stepping switch | External links | External links
Explanation of the way a stepping switch works
Summary of the Rotary Stepper switch with demos
Category:Switches
Category:American inventions
Category:Telephone exchanges
Category:Telecommunications equipment |
Stepping switch | Table of Content | short description, Single-axis stepping switches, Two-axis stepping switch, Applications, References, External links |
Asian supermarket | Short description | alt=|thumb|A selection of instant noodles in a Mitsuwa Marketplace storeIn non-Asian countries, an Asian supermarket largely describes a category of grocery stores that focuses and stocks items and products imported from countries located in the Far East (e.g. East, Southeast and South Asia).
These stores go further than a typical quintessential supermarket in that they sell general merchandise, goods, and services related to specific Asian countries of origin, immigrant communities or the ethnic enclave that the store may be located in.
They would also often tend to diversify by carrying products from other fellow Asian countries; Japanese supermarkets would carry some Chinese, Indonesian, Korean and Singaporean products; Korean supermarkets carry some Chinese and Japanese products; Taiwanese supermarkets carry Chinese, Korean, Japanese, Thai, Vietnamese products, and so on. |
Asian supermarket | Overview | Overview
Asian supermarkets carry items and ingredients generally well-suited for Asian cuisines and simply not found or considerably more expensive in most Western supermarkets, due to low turnover and small quantities.
While it primarily caters to a single particular Asian cultural group, many also additionally caters to other Asian immigrant groups who do not have easy access to foodstuffs from their country of origin. These are prevalent in Asian enclaves in the United States and Canada. Urban centers such as New York City, Los Angeles, Washington, D.C., San Diego, Chicago, Houston, Dallas, Atlanta, San Francisco, Philadelphia, St. Louis, and Seattle have Chinatowns, Little Indias, Little Saigons, Koreatowns, or Japantowns and other ethnic neighborhoods with specialty small business, but surrounding areas or smaller cities will have Asian supermarkets providing the same but reduced amenities for the same purposes.
thumb|Nijiya Market, a Japanese chain market, in San Diego, California|alt=Sometimes, these markets are surrounded by an Asian-themed strip mall. The markets are generally ethnocentric and may be mainly Chinese, Indonesian, Japanese or Filipino market; however, in many areas such supermarkets cater to a more diverse Asian population as a means of diversification and Pan-Asian cooperation.
It is this diversity that led to the establishment of Pan-Asian goods in a one-stop shop with aisles selling foods in common and others dedicated to other groups such as Pakistani, Bangladeshi, Indian, Malaysian, Singaporean, Vietnamese, Thai, Taiwanese, Korean, and others. Some Asian supermarkets in Australia and the United States also stock Pacific food items aimed at the Pacific Islander communities in those countries.Example of Asian supermarket that also stocks food items from the Pacific Islands. Similarly, some Asian supermarkets in the Netherlands stock items from Suriname aimed at the large Surinamese communities of Indian and Javanese origins found in the country.
Despite sourcing from many multiple nations, items stocked are very different depending on their target ethnic market. For example, in Chinese and Vietnamese supermarkets it is common for animal meat to be hung on hooks for display; in Japanese supermarkets this is less common except for seafood. Chinese supermarkets may also carry Japanese products but the range of selection would be very limited as compared to a Japanese supermarket. For example, for green tea, in a Japanese market, an entire aisle may be dedicated to it, stocking a wide variety and grades of regional loose-leaf teas, whereas the Chinese market may simply carry a few brands of Japanese tea bags and bottled teas, while focusing on chrysanthemum tea. |
Asian supermarket | Chains | Chains
thumb|T&T Supermarket chain in Toronto, Ontario|alt=T & T Supermarket chain in Toronto, Ontario
Though most Asian supermarkets tend to be neighborhood-oriented, small and independent and may carry similar or even identical names, many large chains of stores have floor area that is comparable to other American supermarket chain stores. Among the largest of these chains is H Mart, which has 66 locations.
Major chains include:
Chinese and Pan-Asian: Hong Kong Supermarket (US-6 locations), Kam Man Food (East Coast US), Hoo Hing (UK), Wing Yip (UK), Miracle Supermarket (Australia-New South Wales), Grand Asia Market (US), Nations Fresh Foods (Canada-Ontario), Lion Supermarket (US- Silicon Valley), zTao Marketplace (US-Texas, Georgia), G&L Supermarket (Good Luck Plaza ) (Chinese, Southeast Asian, Indian, Korean and Japanese) (Australia-New South Wales) Asian Foods (Chinese, Japanese, Thai, Malaysian, Indonesian, Singaporean, Indian, Sri Lankan, Bangladeshi, Pakistani, Filipino and Korean) (Australia-Queensland) iFresh Supermarket
Filipino and Pan-Asian: Seafood City (US-25 stores, Canada-5 stores), Island Pacific Supermarket (US-California), Manila Oriental Market (Filipino, Japanese, Chinese, Vietnamese, Thai, Indian and Korean) (US-California), Amazing Oriental (東方行) (Chinese, Indian, Japanese, Malaysian, Filipino, Sri Lankan, Taiwanese, Vietnamese, Indonesian, Korean, Singaporean, Surinamese and Thai) (Netherlands)
Hmong and Pan-Asian: Shuang Hur Supermarket (3 stores in Minneapolis and Saint Paul, Minnesota
Indian and Pan-Asian: Patel Brothers (US-54 stores), Subzi Mandi Cash & Carry (US-10 stores, Canada-5 stores), Sabzi Mandi (Canada-7 stores), Panchvati Supermarket (Canada-5 stores), MKS Spices 'N Things (Australia-Victoria), Asian Food Centre (Canada-7 stores), India Town Food Centre (Canada-2 stores).
Japanese: Marukai (US, 14 stores), Nijiya Market (US, 12 stores), Mitsuwa Marketplace (US, 11 stores), Uwajimaya (Greater Seattle and Greater Portland, OR), Yaohan (defunct)
Korean: H Mart (84 stores as of 2021), Oseyo (UK, 20 stores), Lotte Plaza (US, 14 stores), Zion Market (US, 6 stores), K-Mart (FR, 6 stores), Assi Market (US, 3 stores), Arirang Supermarket (US, 2 stores), Galleria Supermarket (Canada-Greater Toronto)
Taiwanese: 99 Ranch Market (US), T & T Supermarket (Canada), 168 Market (US-California, Nevada, 6 stores)
Vietnamese: Shun Fat Supermarket (US-15 locations)
Indonesian: Maya Asian Market, currently 1 store in Lynnwood, Washington |
Asian supermarket | Online | Online
Due to concentration of immigrant communities in metropolitan areas, few Asian supermarket chain stores are located in non-metro areas. In order to better compete and serve this market, a few of these chains have begun online sales, which compete directly with the likes of general online e-commerce merchandisers such as Amazon.com, Walmart.com, Shopee and Rakuten. |
Asian supermarket | In Asia | In Asia
Major operators in Asia such as AEON, Don Quijote (Don Don Donki) and Jusco operate somewhat like Asian supermarkets, as they offer products not normally found in their home countries; as such they also serve as a platform for selling regional Asian cuisines and foods from their origin country. An example would be selling a Singaporean drink in Japan and vice versa, when they are both Asian countries. |
Asian supermarket | Operations | Operations
Most of these supermarkets are started and operated by Asian immigrant entrepreneurs and their families. Others are started by investors of existing corporate conglomerates already headquartered in Asia, namely Mainland China, Hong Kong, Japan, the Philippines, Singapore, South Korea, and Taiwan.
Asian supermarkets can range from small mom-and-pop grocery stores to large big-box stores and may cater specifically to one ethnic Asian immigrant group or to a wide pan-Asian crowd. They serve the generally unserved or underserved immigrant and descendant population. They are usually the main attraction for food shopping within overseas Asian shopping malls and Chinatowns. Asian supermarkets may re-occupy older buildings formerly anchored by mainstream regional or national supermarket chains.
thumb|Kam Man Food in Quincy, Massachusetts|alt= Chinese shopping centers and supermarkets have been constructed using traditional Chinese architecture, and provide services catered toward immigrant customers. Examples include Asian restaurants, beauty salons, bakeries, foreign film rental stores, travel agencies, book stores, and other businesses.
In recent years, some mainstream markets have attempted to compete with Asian supermarkets for the minority customer base by stocking certain Asian goods as well as directing marketing towards various Asian ethnic immigrant populations. Conversely, some Asian supermarkets attempt to appeal to the general population. Asian markets are reputed to have lower prices than the mainstream chains.
Asian supermarkets represent a new trend in which Asian immigrants no longer settle in old enclaves such as Chinatown, San Francisco but in suburbs where shopping centers provide services as well as cultural amenities, such as hosting ethnic festivals, shows and dance.
One of the major redevelopments highlighted in the press has been Buford Highway in the Atlanta suburb of Doraville, Georgia, where Asian supermarkets have done brisk business in a once-blighted neighborhood. Such supermarkets have also revitalized the once-rundown sections of Bellaire Blvd in Houston, Texas, and turned it into a thriving new Asian shopping district. There are also many competing Chinese supermarkets in the Southern California Chinatowns and Vietnamese markets anchoring communities such as Little Saigon. |
Asian supermarket | Products | Products
alt=|thumb|Shelves of Asian canned goods in a 99 Ranch Market store
+Asian branded productsCategoryExamples Vegetable nori/gim and green laver (parae/aonori), bamboo shoots, bok choy, bean sprouts, welsh onions, ginger, kang kong, mustard greens, daikonFruitdurian, pomelo, Asian pear, mango, lychee, mangosteen, rambutan, coconut Grain jasmine rice, basmati rice Beverage soy milk, chrysanthemum tea, bubble tea, sake, soju, green tea, thai iced tea, oolong tea, Ramune Seasoning chili, soy sauce, Phu Quoc fish sauce Ingredients black bean, century eggs, ginseng Packaged snacks prawn crackers, Pocky, rice cakes, Tobi nuts, dried Jackfruit Merchandise rice cookers, woks, fashion magazines, newspapers, cigarettes Bakery Chinese pastries, Curry puffs, banh mi Seafood fish, shellfish, sushi Delicacies sea cucumber, shark fin, abalonesMeat Chinese sausage
+ International brandsControlling polityBrand Australia Maharajah's Choice, Pandaroo, The Han Kitchen, Soul Papa & Co, bubbleme China Haw flakes, Tsingtao Beer Canada Brar's, Nanak's, Surati Cambodia Angkor Beer Hong Kong Lee Kum Kee, Vitasoy, Bamboo Garden, Sau Tao, Amoy Foods, Swire Sugars India Amul, India Gate, Old Monk Indonesia Indofood, Kopiko, Teh botol, Bintang Beer Japan Calbee, Calpis, Glico, Kikkoman (JFC), Meiji, Maruchan, Nissin Foods, Shirakiku, Pocari Sweat, Ajinomoto, Yamasa, S&B, House Foods, Kagome, Sapporo, Morinaga (Mori-Nu), Yakult, Asahi, Kirin, Ito-en, Yamamotoyama, Kadoya, Nagatanien(ja), Nishimoto Korea Binggrae, CJ CheilJedang, Crown, Dongwon, Haitai, HiteJinro, Lotte, Nongshim, Orion, Ottogi, Paldo, Pulmuone, Samyang Food Malaysia Brahim's, Baba's (), Julie's, Lingam's, Munchy's, Rotiboy, OldTown White Coffee Nepal Wai Wai Philippines Barrio Fiesta, Goldilocks, Tobi Nuts, San Miguel Brewery, Mama Sita's Singapore 100plus, Axe Brand, Ayam, Asian Home Gourmet, Irvins, Koka noodles, Marigold, Pokka, Prima Taste, Tiger Beer, Yeo's, Tee Yih Jia, Tiger Balm, TWG Tea, Ya Kun Sri Lanka Dilmah Taiwan Uni-President Enterprises Corporation, Wei Chuan, I-Mei, Companion Foods, Chin Chin, Ve Wong, Kimlan Foods, Hsin Tung Yang, Want Want, Chimei Thailand Chaokoh, Aroy-D, Thai President Foods (Mama), Tiparos, Lobo, Malee, Charoen Pokphand Foods, Vitamilk Vietnam Vinamilk, Bao Long, Trung Nguyên United Kingdom Patak's, Sharwood's United States King's Hawaiian, Thai Kitchen and Simply Asia, Sriracha, VH, Sun Noodle, Sun Foods LLC (Hinode) |
Asian supermarket | See also | See also
Religious goods store
Chinatown
Koreatown
Japantown
Vietnamtown
Little Manila
Night market
Wet market
Toko (shop), similar type of shop in the Netherlands
List of supermarket chains in the United States |
Asian supermarket | References | References |
Asian supermarket | External links | External links
"The New Chinatown? Try the Asian Mall", The New York Times—article on the growing trend of Asian supermarkets in the United States
Asian food dollars go east—article on impact of Asian supermarkets in New Zealand
"Grass Jelly, Anyone? 99 Ranch Brings Asian Flavor to East Bay"—newspaper article from Berkeley, CA
Category:Asian cuisine
Category:Asian drinks
Category:Supermarkets by culture |
Asian supermarket | Table of Content | Short description, Overview, Chains, Online, In Asia, Operations, Products, See also, References, External links |
Category:Cinemaware games | [[Category:Video games by company]] | Category:Video games by company |
Category:Cinemaware games | Table of Content | [[Category:Video games by company]] |
Anodizing | short description | right|thumb|These carabiners have an anodized aluminium surface that has been dyed; they are made in many colors.
Anodizing is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts.
The process is called anodizing because the part to be treated forms the anode electrode of an electrolytic cell. Anodizing increases resistance to corrosion and wear, and provides better adhesion for paint primers and glues than bare metal does. Anodic films can also be used for several cosmetic effects, either with thick porous coatings that can absorb dyes or with thin transparent coatings that add reflected light wave interference effects.
Anodizing is also used to prevent galling of threaded components and to make dielectric films for electrolytic capacitors. Anodic films are most commonly applied to protect aluminium alloys, although processes also exist for titanium, zinc, magnesium, niobium, zirconium, hafnium, and tantalum. Iron or carbon steel metal exfoliates when oxidized under neutral or alkaline micro-electrolytic conditions; i.e., the iron oxide (actually ferric hydroxide or hydrated iron oxide, also known as rust) forms by anoxic anodic pits and large cathodic surface, these pits concentrate anions such as sulfate and chloride accelerating the underlying metal to corrosion. Carbon flakes or nodules in iron or steel with high carbon content (high-carbon steel, cast iron) may cause an electrolytic potential and interfere with coating or plating. Ferrous metals are commonly anodized electrolytically in nitric acid or by treatment with red fuming nitric acid to form hard black Iron(II,III) oxide. This oxide remains conformal even when plated on wiring and the wiring is bent.
Anodizing changes the microscopic texture of the surface and the crystal structure of the metal near the surface. Thick coatings are normally porous, so a sealing process is often needed to achieve corrosion resistance. Anodized aluminium surfaces, for example, are harder than aluminium but have low to moderate wear resistance that can be improved with increasing thickness or by applying suitable sealing substances. Anodic films are generally much stronger and more adherent than most types of paint and metal plating, but also more brittle. This makes them less likely to crack and peel from ageing and wear, but more susceptible to cracking from thermal stress. |
Anodizing | History | History
Anodizing was first used on an industrial scale in 1923 to protect Duralumin seaplane parts from corrosion. This early chromic acid–based process was called the Bengough–Stuart process and was documented in British defence specification DEF STAN 03-24/3. It is still used today despite its legacy requirements for a complicated voltage cycle now known to be unnecessary. Variations of this process soon evolved, and the first sulfuric acid anodizing process was patented by Gower and O'Brien in 1927. Sulfuric acid soon became and remains the most common anodizing electrolyte.
Oxalic acid anodizing was first patented in Japan in 1923 and later widely used in Germany, particularly for architectural applications. Anodized aluminium extrusion was a popular architectural material in the 1960s and 1970s, but has since been displaced by cheaper plastics and powder coating.. The phosphoric acid processes are the most recent major development, so far only used as pretreatments for adhesives or organic paints.. A wide variety of proprietary and increasingly complex variations of all these anodizing processes continue to be developed by industry, so the growing trend in military and industrial standards is to classify by coating properties rather than by process chemistry. |
Anodizing | Aluminium | Aluminium
thumb|upright|Colored anodized aluminium key blanks
Aluminium alloys are anodized to increase corrosion resistance and to allow dyeing (coloring), improved lubrication, or improved adhesion. However, anodizing does not increase the strength of the aluminium object. The anodic layer is insulative..
When exposed to air at room temperature, or any other gas containing oxygen, pure aluminium self-passivates by forming a surface layer of amorphous aluminium oxide 2 to 3 nm thick,. which provides very effective protection against corrosion. Aluminium alloys typically form a thicker oxide layer, 5–15 nm thick, but tend to be more susceptible to corrosion. Aluminium alloy parts are anodized to greatly increase the thickness of this layer for corrosion resistance. The corrosion resistance of aluminium alloys is significantly decreased by certain alloying elements or impurities: copper, iron, and silicon,. so 2000-, 4000-, 6000 and 7000-series Al alloys tend to be most susceptible.
Although anodizing produces a very regular and uniform coating, microscopic fissures in the coating can lead to corrosion. Further, the coating is susceptible to chemical dissolution in the presence of high- and low-pH chemistry, which results in stripping the coating and corrosion of the substrate. To combat this, various techniques have been developed either to reduce the number of fissures, to insert more chemically stable compounds into the oxide, or both. For instance, sulphuric-anodized articles are normally sealed, either through hydro-thermal sealing or precipitating sealing, to reduce porosity and interstitial pathways that allow corrosive ion exchange between the surface and the substrate. Precipitating seals enhance chemical stability but are less effective in eliminating ionic exchange pathways. Most recently, new techniques to partially convert the amorphous oxide coating into more stable micro-crystalline compounds have been developed that have shown significant improvement based on shorter bond lengths.
Some aluminium aircraft parts, architectural materials, and consumer products are anodized. Anodized aluminium can be found on MP3 players, smartphones, multi-tools, flashlights, cookware, cameras, sporting goods, firearms, window frames, roofs, in electrolytic capacitors, and on many other products both for corrosion resistance and the ability to retain dye. Although anodizing only has moderate wear resistance, the deeper pores can better retain a lubricating film than a smooth surface would.
Anodized coatings have a much lower thermal conductivity and coefficient of linear expansion than aluminium. As a result, the coating will crack from thermal stress if exposed to temperatures above 80 °C (353 K). The coating can crack, but it will not peel. The melting point of aluminium oxide is 2050°C (2323K), much higher than pure aluminium's 658°C (931K). This and the insulativity of aluminium oxide can make welding more difficult.
In typical commercial aluminium anodizing processes, the aluminium oxide is grown down into the surface and out from the surface by equal amounts. Therefore, anodizing will increase the part dimensions on each surface by half the oxide thickness. For example, a coating that is 2 μm thick will increase the part dimensions by 1 μm per surface. If the part is anodized on all sides, then all linear dimensions will increase by the oxide thickness. Anodized aluminium surfaces are harder than aluminium but have low to moderate wear resistance, although this can be improved with thickness and sealing. |
Anodizing | Process | Process |
Anodizing | Desmut | Desmut
A desmut solution can be applied to the surface of aluminium to remove contaminates. Nitric acid is typically used to remove smut (residue), but is being replaced because of environmental concerns. |
Anodizing | Electrolysis | Electrolysis
The anodized aluminium layer is created by passing a direct current through an electrolytic solution, with the aluminium object serving as the anode (the positive electrode in an electrolytic cell). The current releases hydrogen at the cathode (the negative electrode) and oxygen at the surface of the aluminium anode, creating a build-up of aluminium oxide. Alternating current and pulsed current is also possible but rarely used. The voltage required by various solutions may range from 1 to 300 V DC, although most fall in the range of 15 to 21 V. Higher voltages are typically required for thicker coatings formed in sulfuric and organic acid. The anodizing current varies with the area of aluminium being anodized and typically ranges from 30 to 300 A/m2.
Aluminium anodizing (eloxal or Electrolytic Oxidation of Aluminium) is usually performed in an acidic solution, typically sulphuric acid or chromic acid, which slowly dissolves the aluminium oxide. The acid action is balanced with the oxidation rate to form a coating with nanopores, 10–150 nm in diameter. These pores are what allow the electrolyte solution and current to reach the aluminium substrate and continue growing the coating to greater thickness beyond what is produced by auto-passivation.. These pores allow for the dye to be absorbed, however, this must be followed by sealing or the dye will not stay. Dye is typically followed up by a clean nickel acetate seal. Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches break through the dyed layer.
Conditions such as electrolyte concentration, acidity, solution temperature, and current must be controlled to allow the formation of a consistent oxide layer. Harder, thicker films tend to be produced by more concentrated solutions at lower temperatures with higher voltages and currents. The film thickness can range from under 0.5 micrometers for bright decorative work up to 150 micrometers for architectural applications. |
Anodizing | Dual-finishing | Dual-finishing
Anodizing can be performed in combination with chromate conversion coating. Each process provides corrosion resistance, with anodizing offering a significant advantage when it comes to ruggedness or physical wear resistance. The reason for combining the processes can vary, however, the significant difference between anodizing and chromate conversion coating is the electrical conductivity of the films produced. Although both stable compounds, chromate conversion coating has a greatly increased electrical conductivity. Applications where this may be useful are varied, however the issue of grounding components as part of a larger system is an obvious one.
The dual finishing process uses the best each process has to offer, anodizing with its hard wear resistance and chromate conversion coating with its electrical conductivity.
The process steps can typically involve chromate conversion coating the entire component, followed by a masking of the surface in areas where the chromate coating must remain intact. Beyond that, the chromate coating is then dissolved in unmasked areas. The component can then be anodized, with anodizing taking to the unmasked areas. The exact process will vary dependent on service provider, component geometry and required outcome. It helps to protect aluminium article. |
Anodizing | Widely used specifications | Widely used specifications
The most widely used anodizing specification in the US is a U.S. military spec, MIL-A-8625, which defines three types of aluminium anodizing. Type I is chromic acid anodizing, Type II is sulphuric acid anodizing, and Type III is sulphuric acid hard anodizing. Other anodizing specifications include more MIL-SPECs (e.g., MIL-A-63576), aerospace industry specs by organizations such as SAE, ASTM, and ISO (e.g., AMS 2469, AMS 2470, AMS 2471, AMS 2472, AMS 2482, ASTM B580, ASTM D3933, ISO 10074, and BS 5599), and corporation-specific specs (such as those of Boeing, Lockheed Martin, Airbus and other large contractors). AMS 2468 is obsolete. None of these specifications define a detailed process or chemistry, but rather a set of tests and quality assurance measures which the anodized product must meet. BS 1615 guides the selection of alloys for anodizing. For British defense work, a detailed chromic and sulfuric anodizing processes are described by DEF STAN 03-24/3 and DEF STAN 03-25/3 respectively. STAN 03-24/3 STAN 03-25/3 |
Anodizing | Chromic acid (Type I) | Chromic acid (Type I)
The oldest anodizing process uses chromic acid. It is widely known as the Bengough-Stuart process but, due to the safety regulations regarding air quality control, is not preferred by vendors when the additive material associated with type II doesn't break tolerances. In North America, it is known as Type I because it is so designated by the MIL-A-8625 standard, but it is also covered by AMS 2470 and MIL-A-8625 Type IB. In the UK it is normally specified as Def Stan 03/24 and used in areas that are prone to come into contact with propellants etc. There are also Boeing and Airbus standards. Chromic acid produces thinner, 0.5 μm to 18 μm (0.00002" to 0.0007")US Military Specification MIL-A-8625, ASSIST database more opaque films that are softer, ductile, and to a degree self-healing. They are harder to dye and may be applied as a pretreatment before painting. The method of film formation is different from using sulfuric acid in that the voltage is ramped up through the process cycle. |
Anodizing | Sulfuric acid (Type II & III) | Sulfuric acid (Type II & III)
Sulfuric acid is the most widely used solution to produce an anodized coating. Coatings of moderate thickness 1.8 μm to 25 μm (0.00007" to 0.001") are known as Type II in North America, as named by MIL-A-8625, while coatings thicker than 25 μm (0.001") are known as Type III, hard-coat, hard anodizing, or engineered anodizing. Very thin coatings similar to those produced by chromic anodizing are known as Type IIB. Thick coatings require more process control, and are produced in a refrigerated tank near the freezing point of water with higher voltages than the thinner coatings. Hard anodizing can be made between 13 and 150 μm (0.0005" to 0.006") thick. Anodizing thickness increases wear resistance, corrosion resistance, ability to retain lubricants and PTFE coatings, and electrical and thermal insulation. Sealing Type III will improve corrosion resistance at the cost of reducing abrasion resistance. Sealing will reduce this greatly. Standards for thin (Soft/Standard) sulfuric anodizing are given by MIL-A-8625 Types II and IIB, AMS 2471 (undyed), and AMS 2472 (dyed), BS EN ISO 12373/1 (decorative), BS 3987 (Architectural). Standards for thick sulphuric anodizing are given by MIL-A-8625 Type III, AMS 2469, BS ISO 10074, BS EN 2536 and the obsolete AMS 2468 and DEF STAN 03-26/1. |
Anodizing | Organic acid | Organic acid
Anodizing can produce yellowish integral colors without dyes if it is carried out in weak acids with high voltages, high current densities, and strong refrigeration. Shades of color are restricted to a range which includes pale yellow, gold, deep bronze, brown, grey, and black. Some advanced variations can produce a white coating with 80% reflectivity. The shade of color produced is sensitive to variations in the metallurgy of the underlying alloy and cannot be reproduced consistently.
Anodizing in some organic acids, for example malic acid, can enter a 'runaway' situation, in which the current drives the acid to attack the aluminium far more aggressively than normal, resulting in huge pits and scarring. Also, if the current or voltage are driven too high, 'burning' can set in; in this case, the supplies act as if nearly shorted and large, uneven and amorphous black regions develop.
Integral color anodizing is generally done with organic acids, but the same effect has been produced in laboratories with very dilute sulfuric acid. Integral color anodizing was originally performed with oxalic acid, but sulfonated aromatic compounds containing oxygen, particularly sulfosalicylic acid, have been more common since the 1960s. Thicknesses of up to 50 μm can be achieved. Organic acid anodizing is called Type IC by MIL-A-8625. |
Anodizing | Phosphoric acid | Phosphoric acid
Anodizing can be carried out in phosphoric acid, usually as a surface preparation for adhesives. This is described in standard ASTM D3933. |
Anodizing | Borate and tartrate baths | Borate and tartrate baths
Anodizing can also be performed in borate or tartrate baths in which aluminium oxide is insoluble. In these processes, the coating growth stops when the part is fully covered, and the thickness is linearly related to the voltage applied. These coatings are free of pores, relative to the sulfuric and chromic acid processes. This type of coating is widely used to make electrolytic capacitors because the thin aluminium films (typically less than 0.5 μm) would risk being pierced by acidic processes. |
Anodizing | Plasma electrolytic oxidation | Plasma electrolytic oxidation
Plasma electrolytic oxidation is a similar process, but where higher voltages are applied. This causes sparks to occur and results in more crystalline/ceramic type coatings. |
Anodizing | Other metals | Other metals |
Anodizing | Magnesium | Magnesium
Magnesium is anodized primarily as a primer for paint. A thin (5 μm) film is sufficient for this. Thicker coatings of 25 μm and up can provide mild corrosion resistance when sealed with oil, wax, or sodium silicate. Standards for magnesium anodizing are given in AMS 2466, AMS 2478, AMS 2479, and ASTM B893. |
Anodizing | Niobium | Niobium
Niobium anodizes in a similar fashion to titanium with a range of attractive colors being formed by interference at different film thicknesses. Again the film thickness is dependent on the anodizing voltage. Uses include jewelry and commemorative coins. |
Anodizing | Stainless steel | Stainless steel
thumb|right|anodized stainless steel test plate (molybdate based solution)
Stainless steel can be anodized in baths containing sulphuric acid and hexavalent chromium compounds.Handbuch der Galvanotechnik Band III, eds. H. Dettner and J. Elze,Munich 1969.,p.291Baths containing NaOH or KOH solutions can be used too.As hexavalent chromium compounds are prohibited for use in the EU based on ROHS regulations and are toxic and carcinogenic, solutions based on molybdate are proposed as a replacement (e.g. molybdate 30-100g/ boric acid 10-18 g/manganese sulfate 0.5 - 5 g/1 liter of water, 0.1 - 20 A/dm2, 0.1–15 minutes). |
Anodizing | Tantalum | Tantalum
Tantalum anodizes similarly to titanium and niobium with a range of attractive colors being formed by interference at different film thicknesses. Again the film thickness is dependent on the anodizing voltage and typically ranges from 18 to 23 Angstroms per volt depending on electrolyte and temperature. Uses include tantalum capacitors. |
Anodizing | Titanium | Titanium
upright=1.2|thumb|Selected colors achievable through anodization of titanium
An anodized oxide layer has a thickness in the range of to several micrometers. Standards for titanium anodizing are given by AMS 2487 and AMS 2488.
AMS 2488 Type III anodizing of titanium generates an array of different colors without dyes, for which it is sometimes used in art, costume jewellery, body piercing jewellery and wedding rings. The color formed is dependent on the thickness of the oxide (which is determined by the anodizing voltage); it is caused by the interference of light reflecting off the oxide surface with light travelling through it and reflecting off the underlying metal surface. AMS 2488 Type II anodizing produces a thicker matte grey finish with higher wear resistance. |
Anodizing | Zinc | Zinc
Zinc is rarely anodized, but a process was developed by the International Lead Zinc Research Organization and covered by MIL-A-81801. A solution of ammonium phosphate, chromate and fluoride with voltages of up to 200 V can produce olive green coatings up to 80 μm thick. The coatings are hard and corrosion resistant.
Zinc or galvanized steel can be anodized using DC at lower voltages (20–30 V) in silicate baths containing varying concentrations of sodium silicate, sodium hydroxide, borax, sodium nitrite, and nickel sulfate.Imam, M. A., Moniruzzaman, M., & Mamun, M. A. ANODIZING OF ZINC FOR IMPROVED SURFACE PROPERTIES. Proceedings of a meeting held 20–24 November 2011, 18th International Corrosion Congress, Perth, Australia, pp. 199–206 (2012), |
Anodizing | Dyeing | Dyeing
thumb|Colored iPod Mini cases are dyed following anodizing and before thermal sealing.
The most common anodizing processes, for example, sulphuric acid on aluminium, produce a porous surface which can accept dyes easily. The number of dye colors is almost endless; however, the colors produced tend to vary according to the base alloy. The most common colors in the industry, due to them being relatively cheap, are yellow, green, blue, black, orange, purple and red. Though some may prefer lighter colors, in practice they may be difficult to produce on certain alloys such as high-silicon casting grades and 2000-series aluminium-copper alloys. Another concern is the "lightfastness" of organic dyestuffs—some colors (reds and blues) are particularly prone to fading. Black dyes and gold produced by inorganic means (ferric ammonium oxalate) are more lightfast. Dyed anodizing is usually sealed to reduce or eliminate dye bleed out. White color cannot be applied due to the larger molecule size than the pore size of the oxide layer.
Alternatively, metal (usually tin) can be electrolytically deposited in the pores of the anodic coating to provide more lightfast colors. Metal dye colors range from pale champagne to black. Bronze shades are commonly used for architectural metals. Alternatively, the color may be produced integral to the film. This is done during the anodizing process using organic acids mixed with the sulfuric electrolyte and a pulsed current.
Splash effects are created by dying the unsealed porous surface in lighter colors and then splashing darker color dyes onto the surface. Aqueous and solvent-based dye mixtures may also be alternately applied since the colored dyes will resist each other and leave spotted effects.
alt=aluminum anodizing interference color|thumb|Anodizing interference colors
Another interesting coloring method is anodizing interference coloring. The thin oil film resting on the water's surface displays a rainbow hue due to the interference between light reflected from the water-oil interface and the oil film's surface. Because the oil film's thickness isn't regulated, the resulting rainbow color appears random.
In the anodizing coloring of aluminum, desired colors are achieved by depositing a controllably thick metal layer (typically tin) at the base of the porous structure. This involves reflections on the aluminum substrate and the upper metal surface. The color resulting from interference shifts from blue, green, and yellow to red as the deposited metal layer thickens. Beyond a specific thickness, the optical interference vanishes, and the color turns bronze. Interference-colored anodized aluminum parts exhibit a distinctive quality: their color varies when viewed from different angles. The interference coloring involves a 3-step process: sulfuric acid anodizing, electrochemical modification of the anodic pore, and metal (tin) deposition. |
Anodizing | Sealing | Sealing
Sealing is the final step in the anodizing process. Acidic anodizing solutions produce pores in the anodized coating. These pores can absorb dyes and retain lubricants but are also an avenue for corrosion. When lubrication properties are not critical, they are usually sealed after dyeing to increase corrosion resistance and dye retention. There are three most common types of sealing.
Long immersion in boiling-hot——deionized water or steam is the simplest sealing process, although it is not completely effective and reduces abrasion resistance by 20%. The oxide is converted into its hydrated form and the resulting swelling reduces the porosity of the surface.
Mid-temperature sealing process which works at in solutions containing organic additives and metal salts. However, this process will likely leach the colors.
Cold sealing process, where the pores are closed by impregnation of a sealant in a room-temperature bath, is more popular due to energy savings. Coatings sealed in this method are not suitable for adhesive bonding. Teflon, nickel acetate, cobalt acetate, and hot sodium or potassium dichromate seals are commonly used. MIL-A-8625 requires sealing for thin coatings (Types I and II) and allows it as an option for thick ones (Type III). |
Anodizing | Cleaning | Cleaning
Anodized aluminium surfaces that are not regularly cleaned are susceptible to panel edge staining, a unique type of surface staining that can affect the structural integrity of the metal. |
Anodizing | Environmental impact | Environmental impact
Anodizing is one of the more environmentally friendly metal finishing processes. Except for organic (aka integral color) anodizing, the by-products contain only small amounts of heavy metals, halogens, or volatile organic compounds. Integral color anodizing produces no VOCs, heavy metals, or halogens as all of the byproducts found in the effluent streams of other processes come from their dyes or plating materials. The most common anodizing effluents, aluminium hydroxide and aluminium sulfate, are recycled for the manufacturing of alum, baking powder, cosmetics, newsprint and fertilizer or used by industrial wastewater treatment systems. |
Anodizing | Mechanical considerations | Mechanical considerations
Anodizing will raise the surface since the oxide created occupies more space than the base metal converted. This will generally not be of consequence except where there are tight tolerances. If so, the thickness of the anodizing layer has to be taken into account when choosing the machining dimension. A general practice on engineering drawing is to specify that "dimensions apply after all surface finishes". This will force the machine shop to take into account the anodization thickness when performing the final machining of the mechanical part before anodization. Also in the case of small holes threaded to accept screws, anodizing may cause the screws to bind, thus the threaded holes may need to be chased with a tap to restore the original dimensions. Alternatively, special oversize taps may be used to precompensate for this growth. In the case of unthreaded holes that accept fixed-diameter pins or rods, a slightly oversized hole to allow for the dimension change may be appropriate. Depending on the alloy and thickness of the anodized coating, the same may have a significantly negative effect on fatigue life. Conversely, anodizing may increase fatigue life by preventing corrosion pitting. |
Anodizing | See also | See also
Black oxide
Phosphate conversion coating
Electrochemical coloring of metals |
Anodizing | References | References |
Anodizing | Citations | Citations |
Anodizing | Bibliography | Bibliography
|
Anodizing | External links | External links
"Titanium in Technicolor", an article on anodizing titanium from Theodore Gray's How2.0 column in Popular Science
Category:Coatings
Category:Corrosion prevention
Category:Electrolysis
Category:Metallurgical processes |
Anodizing | Table of Content | short description, History, Aluminium, Process, Desmut, Electrolysis, Dual-finishing, Widely used specifications, Chromic acid (Type I), Sulfuric acid (Type II & III), Organic acid, Phosphoric acid, Borate and tartrate baths, Plasma electrolytic oxidation, Other metals, Magnesium, Niobium, Stainless steel, Tantalum, Titanium, Zinc, Dyeing, Sealing, Cleaning, Environmental impact, Mechanical considerations, See also, References, Citations, Bibliography, External links |
Vyšehrad | Short description | thumb|Vyšehrad from the southwest
Vyšehrad (German: Wyschehrad, Prager Hochburg, English: "upper castle") is a historic fort in Prague, Czech Republic, just over 3 km southeast of Prague Castle, on the east bank of the Vltava River.Granville Baker, From a Terrace in Prague, pg. 44, Echo Library (2008), It was probably built in the 10th century. Inside the fort are the Basilica of St. Peter and St. Paul and the Vyšehrad Cemetery, containing the remains of many famous Czechs, such as Antonín Dvořák, Bedřich Smetana, Karel Čapek, and Alphonse Mucha. It also contains Prague's oldest Rotunda of St. Martin, from the 11th century. |
Vyšehrad | History | History
Local legend holds that Vyšehrad was the location of the first settlement which later became Prague, though thus far this claim remains unsubstantiated.
upright|thumb|left|Coat of arms of Vyšehrad from 19 century
Legend has it that Duke Krok founded Vyšehrad while looking for a safer seat than in Budeč. On a steep rock above the Vltava river, he ordered a forest to be cut down and a castle built there. Also according to legend, Prince Křesomysl imprisoned the knight Horymír at Vyšehrad because he damaged silver mines, and Horymír jumped with his horse Šemík over the walls and from Libuše's bath into the river.
When the Přemyslid dynasty settled on the current site of Prague Castle, the two castles maintained opposing spheres of influence for approximately two centuries. The zenith of Vyšehrad was during the second half of the 11th century, when Vratislav II transferred his seat from Prague Castle to Vyšehrad, and the original fort was remodeled as a complex comprising the sovereign's palatial residence, a church, and the seat of the chapter. The period of growth ended around 1140 when Prince Soběslav moved his seat back to Prague Castle.Ehrenberger, Tomaš The Most Beautiful 88 Castles, pg. 114, Kartografie Praha a.s.,
When Holy Roman Emperor Charles IV began to build the Prague Castle in its current dimensions in the early 14th century, the deteriorating Vyšehrad was abandoned as a royal seat. Later the whole complex was renewed by Charles IV and new fortifications, with two gates and a royal palace were built, while the Basilica of Saints Peter and Paul awaited repair. At the beginning of the Hussite Wars, the Hussites conquered and ransacked Vyšehrad in 1420. The troops of King George of Poděbrady did the same in 1448. The castle was then abandoned and became ruined. It underwent a renovation in the 17th century, when the Habsburg monarchy took over the Czech lands after the Thirty Years' War and remodeled it in 1654 as a Baroque fortress, turning it into a training center for the Imperial Army of the Emperor, and later incorporating it into the Baroque city walls.
The present form of Vyšehrad as a fortified residence, with powerful brick ramparts, bastions, and the Tábor and Leopold gates, is a result of Baroque remodeling. The Cihelná brána (Brick gate) is an Empire-style structure, dating from 1841. The main part of the Špička Gate, parts of the Romanesque bridge, and the ruined Gothic lookout tower known as Libušina lázeň (Libuše's Bath) are the only fragments that have been preserved from the Middle Ages. The Romanesque rotunda of St. Martin dates from the second half of the 11th century. The 11th century Basilica of Sts. Peter and Paul, which dominates Vyšehrad, was remodeled in the second half of the 14th century and again in 1885 and 1887 in neo-Gothic style. Vyšehrad and the area around it became part of the capital city in 1883. The area is one of the cadastral districts of the city.
By the twenty-first century, Vyšehrad has become a public park that is a popular site for recreation and celebrations. For example, it is a popular place for Czechs to celebrate New Year's Eve. |
Vyšehrad | Statues | Statues
Josef Václav Myslbek's statues south of the church, originally from Palacký Bridge
Libuše and Přemysl – mythical Czech rulers settled in the 8th century at Vyšehrad
Ctirad and Šárka – the characters of the Maidens' War, when women after the death of Libuše built the castle Děvín lying on the opposite hill of the Vyšehrad
Lumír and Píseň – Lumír was a legendary famous singer who refused to sing celebration song after the Maidens' War ended to the winning men and instead of it sang about the famous Vyšehrad
Záboj and Slavoj – leaders of the rebellion against invasion of the German troops of Charlemagne, allegedly led the victorious battle in 805
Statue of Mikuláš Karlach, Karlach's sets
Statue of Saint Wenceslas by Johann Georg Bendl, northwest bastion
Bust of Václav Štulc, near Nové proboštství building |
Vyšehrad | See also | See also
Battle of Vyšehrad
Libuše
Má vlast (symphonic poem by Bedřich Smetana including a movement Vyšehrad)
Church of Our Lady on the Lawn |
Vyšehrad | References | References |
Vyšehrad | External links | External links
Official Page
Vysehrad Photogallery
Category:Castles in Prague
Category:Districts of Prague
Category:National cultural monuments of the Czech Republic
Category:Prague 2
Category:Forts in the Czech Republic |
Vyšehrad | Table of Content | Short description, History, Statues, See also, References, External links |
Constabulary | Short description | Constabulary may have several definitions:
A civil, non-paramilitary (police) force consisting of police officers called constables. This is the usual definition in the United Kingdom, in which all county police forces once bore the title (and some still do). Constables also exist in some U.S. states including Texas and Pennsylvania.
In English-speaking Canada, the starting rank of all police officers is Constable. The provincial police service of Newfoundland and Labrador is the Royal Newfoundland Constabulary. This term reflects the force’s history of having been modelled after the Royal Irish Constabulary. In this case, Constabulary is used in the same sense in which it is used in the UK.
A large civil police force organised and trained along military lines, which may contain paramilitary elements. This is the usual definition in places outside Great Britain such as the former Royal Irish Constabulary, the former Royal Ulster Constabulary, Royal Newfoundland Constabulary, Jamaica Constabulary Force.
A military or paramilitary type force consisting of soldiers trained for police duties. Mostly established by the United States in the several countries over which it had protective status e.g. Philippine Constabulary; United States Constabulary in West Germany after World War II. These forces also performed military functions by maintaining "mobile forces" of organised units. |
Constabulary | Current UK police services titled "constabulary" | Current UK police services titled "constabulary"
Avon and Somerset Constabulary
Belfast International Airport Constabulary
Cambridgeshire Constabulary
Cheshire Constabulary
Civil Nuclear Constabulary
Derbyshire Constabulary
Durham Constabulary
Gloucestershire Constabulary
Hampshire and Isle of Wight Constabulary
Hampstead Heath Constabulary
Havering Parks Constabulary
Hertfordshire Constabulary
Kew Constabulary
Lancashire Constabulary
Norfolk Constabulary
Suffolk Constabulary |
Constabulary | Current constabularies in the Netherlands{{clarify | Current constabularies in the Netherlands
Royal Marechaussee
Dienst Speciale Interventies
Brigade Speciale Beveiligingsopdrachten |
Constabulary | Historic constabularies | Historic constabularies
Philippines
Philippine Constabulary – created in 1901 by the American colonial administration. It was demilitarised and merged with the Integrated National Police in 1991 to form the Philippine National Police.
Ireland
Royal Irish Constabulary – The United Kingdom's paramilitary police force in Ireland from 1822–1922.
Northern Ireland
Royal Ulster Constabulary – The United Kingdom's police force in Northern Ireland from 1922 – 2001 when it was reformed as the Police Service of Northern Ireland.
Ulster Special Constabulary – a reserve police force from 1920 until it was disbanded in 1970.
Free City of Danzig
Free City of Danzig Police – The law enforcement agency of the semi-autonomous Free City of Danzig from 1919 - 1945.
United States
United States Constabulary – United States Army military gendarmerie force. From 1946 to 1952, in the aftermath of World War II, it acted as an occupation and security force in the U.S. Occupation Zone of West Germany and Austria.
Pennsylvania State Constables – an elected office held in all Pennsylvania townships, boroughs, and cities except Philadelphia; unrelated to the Pennsylvania State Police
Malaysia
North Borneo Constabulary – The paramilitary police force of North Borneo from 1800s to 1963 where it was officially incorporated into Royal Malaysia Police shortly after the formation of Malaysia.
Sarawak Constabulary – The paramilitary police force of Kingdom of Sarawak from 1800s to 1963 where it was officially incorporated into Royal Malaysia Police shortly after the formation of Malaysia.
South Africa
South African Constabulary – The paramilitary gendarmerie force raised by the British Army to police captured areas of the two former Boer republics of the Transvaal and Orange Free State during the Second Boer War from 1900 to 1908. |
Constabulary | Further reading | Further reading
Segal, David R., Brian J. Reed, and David E. Rohall. “Constabulary Attitudes of National Guard and Regular Soldiers in the U.S. Army.” Armed Forces & Society, Jul 1998; Vol. 24: pp. 535–548. http://afs.sagepub.com/cgi/content/abstract/24/4/535
Moskos, Charles C., Jr. “UN Peacekeepers: The Constabulary Ethic and Military Professionalism.” Armed Forces & Society, Jul 1975; Vol. 1: pp. 388–401. |
Constabulary | External links | External links
Category:Law enforcement units |
Constabulary | Table of Content | Short description, Current UK police services titled "constabulary", Current constabularies in the Netherlands{{clarify, Historic constabularies, Further reading, External links |
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Failure modes |
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Visitor center | Short description | thumb|The simplest form of visitor center is an information board, such as this one in Wallendbeen, Australia
A visitor center or centre (see American and British English spelling differences), visitor information center or tourist information centre is a physical location that provides information to tourists. |
Visitor center | Types | Types
A visitor center may be a Civic center at a specific attraction or place of interest, such as a landmark, national park, national forest, or state park, providing information (such as trail maps, and about camp sites, staff contact, restrooms, etc.) and in-depth educational exhibits and artifact displays (for example, about natural or cultural history). Often a film or other media display is used. If the site has permit requirements or guided tours, the visitor center is often the place where these are coordinated.
A tourist information center provides visitors with information on the area's attractions, lodgings, maps, and other items relevant to tourism. These are often operated at the airport or other port of entry, by the local government or chamber of commerce. Some are called information centers. |
Visitor center | Signage | Signage
The Unicode code block Letterlike Symbols allocates a code point (U+2139) for a symbol that may used to identify an information source. The default form is a lower case, roman type, serif, extra bold, letter , but the script typeface form is common. |
Visitor center | Europe | Europe |
Visitor center | United Kingdom | United Kingdom
In the United Kingdom, there is a nationwide network of Tourist Information Centres run by the British Tourist Authority (BTA), represented online by the VisitBritain website and public relations organisation. Other TICs are run by local authorities or through private organisations such as local shops in association with BTA.
In England, VisitEngland promotes domestic tourism.
In Wales, the Welsh Government supports TICs through Visit Wales.
In Scotland, the Scottish Government supports VisitScotland, the official tourist organisation of Scotland, which also operates Tourist Information Centres across Scotland. |
Visitor center | Poland | Poland
In Poland there are special offices and tables giving free information about tourist attractions. Offices are situated in interesting places in popular tourists' destinations and tables usually stay near monuments and important culture |
Visitor center | North America | North America
In North America, a welcome center is a rest area with a visitor center, located after the entrance from one state or province to another state or province or in some cases another country, usually along an Interstate Highway or other freeway. These information centers are operated by the state they are located in. The first example opened on 4 May 1935, next to US 12 in New Buffalo, Michigan, near the Indiana state line.
Many United States cities, such as Houston, Texas and Boca Raton, Florida, as well as counties and other areas smaller than states, also operate welcome centers, though usually with less facilities than state centers have.
In Ontario, there are 11 Ontario Travel Information Centres located along 400-series highways. |
Visitor center | South America | South America |
Visitor center | Peru | Peru
Peru features Iperú, Tourist Information and Assistance, a free service that provides tourist information for domestic and foreign travelers, the information covers destinations, attractions, recommended routes and licensed tourism companies in Peru. It also provides assistance on various procedures or where tourists have problems of various kinds. Iperú receives complaints and suggestions for destinations and tourism companies operating in Peru (lodging, travel agencies, airlines, buses, etc.).
Iperú, Tourist Information and Assistance has a nationwide network represented online by the Peru.travel website, the 24/7 line (51 1) 5748000, and 31 local offices in 13 regions in all over Peru: Lima-Callao, Amazonas, Piura, Lambayeque, La Libertad, Ancash, Arequipa, Tacna, Puno, Ayacucho, Cusco, Tumbes and Iquitos.
The official tourist organization or national tourist board of Peru is PromPerú, a national organization that promotes both tourism and international commerce of this country worldwide. |
Visitor center | Oceania | Oceania
In Australia, most visitor centres are local or state government-run, or in some cases as an association of tourism operators on behalf of the government, usually managed by a board or executive. Those that comply with a national accreditation programme use the italic as pictured. These visitor information centres (often abbreviated as VICs) provide information on the local area, and usually perform services such as accommodation and tour bookings, flight/bus/train/hire car options, and act as the first point of contact a visitor has with the town or region. |
Visitor center | Gallery | Gallery |
Visitor center | See also | See also
Heritage center
Heritage interpretation
Interpretation center
Nature center
United States Capitol Visitor Center |
Visitor center | References | References |
Visitor center | External links | External links
VisitEurope.com EU Visitors Center
Category:Tourism industry |
Visitor center | Table of Content | Short description, Types, Signage, Europe, United Kingdom, Poland, North America, South America, Peru, Oceania, Gallery, See also, References, External links |
Delegated legislation in the United Kingdom | Short description | Delegated legislation or secondary legislation in the United Kingdom is law that is not enacted by a legislative assembly such as the UK Parliament, but made by a government minister, a delegated person or an authorised body under powers given to them by an Act of Parliament.
Statutory instruments are the most frequently used type of secondary legislation, with approximately 3,500 made each year, although only about 1,000 need to be considered by Parliament. They usually have either "Rules", "Order" or "Regulations" in their title.
Secondary legislation is used for a wide variety of purposes such as fixing the date on which an Act of Parliament will come into force; setting fees for a public service; or establishing the details of an Act of Parliament. Delegated legislation is dependent on its parent act, which prescribes its parameters and procedures. Although a large volume of delegated legislation is written without close parliamentary scrutiny, there are statutory instruments to prevent its misuse. |
Delegated legislation in the United Kingdom | Background | Background
Delegated legislation is derived from its parent act, which prescribes its parameters and procedures. Delegated legislation saves parliamentary time by considering matters of technical detail. Such details are prepared by those with relevant expert knowledge.
Through its inherent flexibility, delegated legislation accommodates changing circumstances such as changing fees for public services, developments in science or minor changes in government policy. Delegated legislation allows the rapid drafting of emergency powers. In comparison to acts of Parliament, which may take much time to pass, the flexibility of delegated legislation can be used to solve problems of governance in a timely way.
Delegated legislation is effected by signature of the author or his authorized representative. In the case of the monarch, only his verbal assent is required. A statutory instrument related to the parent act is required to write delegated legislation. It ensures the legislation is catalogued and published by the King's Printer. Exceptions are directions and by-laws where notifications are made to affected entities.
Criticism of delegated legislation may arise because:
it is subject to a lesser degree of parliamentary scrutiny than acts of Parliament.
it may be used to remove from the scrutiny of the parliament matters that are causing difficulty for the government by designating them "matters concerning detail".
within the large volume of delegated legislation there may be little public knowledge of changes being made. However, the statutory instruments are in place to prevent misuse. |
Delegated legislation in the United Kingdom | Types | Types
Delegated legislation can take a variety of forms, each with different uses. The boundaries between the forms are not fixed. The types used will be determined by the wording of the parent Act.
Orders in Council are made by the King on the advice of the Privy Council (the Government). Orders in Council are used in matters of constitutional significance. An example is bringing into force emergency powers to be exercised by ministers.
Orders of Council are made by the lords of the Privy Council. They are used for regulation of professional bodies and the higher education sector.
Ministerial orders are made by ministers.
Orders exercise executive powers of government ministers. An example is the dissolution of a public body. Commencement orders set the date on which an Act, or part of an Act, comes into force.
Regulations set out how an Act is to be implemented and are usually made by ministers.
Rules set out procedures for operation of a government entity such as the courts or the Patent Office. Rules may be made by ministers or, if specified in the parent Act, a senior judge. In Scotland, rules of court take the form of Scottish statutory instruments. Those regulating civil procedure are enacted by the Court of Session and are called Acts of Sederunt. Those regulating criminal procedure are enacted by the High Court of Justiciary as Acts of Adjournal. Acts of Adjournal can modify primary legislation where it relates to criminal judicial procedure.
Schemes are made by commissions to proscribe how entities under their remit are governed. An example is the Charity Commission which supervises charitable organizations.
Directions are a means by which ministers give legally binding instructions to a public body about the way it exercises its functions.
By-laws are laws of limited application (usually restricted to certain places) made by local authorities or certain other bodies (for example, train operating companies or the National Trust) to control the activities of the people in public spaces. |
Delegated legislation in the United Kingdom | Church of England instruments | Church of England instruments
The secondary legislation of the Church of England is known as "instruments". The procedure for the General Synod approving instruments is set out in the standing orders of the General Synod.
After approval of the General Synod, the instruments are presented before Parliament, signed by the Archbishop of Canterbury and the Archbishop of York.
Sometimes they have a different date for when they are "made" and when they come "into force".
So far they have only been used to commence Church of England measures. |
Delegated legislation in the United Kingdom | Crown Dependencies | Crown Dependencies
The Isle of Man has a similar system – the diocesan synod takes the place of the General Synod, Tynwald takes the place of Parliament and the Bishop of Sodor and Man takes the place of the Archbishops of Canterbury and York. Similarly to instruments the United Kingdom, in the Isle of Man orders are presented by the Lord Bishop of Sodor and Man to Tynwald so that to particular provisions of measures can be commenced.
There is no equivalent for the Channel Islands – application of measures to the Channel Islands happens at Parliament. Previously this happened through statutory instruments rather than instruments. Currently the procedure has been modified through the Channel Islands Measure 2020 so it will occur directly in the measure and therefore the instrument that commences the measure. |
Delegated legislation in the United Kingdom | Layout of official documents | Layout of official documents
A document which records delegated legislation will begin with a preamble. It describes the author of the legislation, the related parent Act and its preconditions and any stakeholders. The terms used in the document are determined by the type of delegated legislation it records. For instance, in orders, clauses are called "articles". Clauses may be grouped under headings and in complex delegated legislation, the document may be divided into parts. The main text is followed by any schedules and explanatory notes. |
Delegated legislation in the United Kingdom | Controls | Controls
Delegated legislation is controlled by Parliament and the judiciary. Parliamentary controls include "affirmative resolution procedures" where the legislation requires approval in both houses of parliament and "negative resolution procedures" where the legislation may be vetoed by either house. By convention, the House of Lords will not veto but rather pass a motion to convey its concerns about the legislation.
Judicial control of delegated legislation is exercised through judicial review. Delegated legislation can be quashed by a court if it is found to be ultra vires (outside the parameters defined in the parent act). There are two types of ultra vires. In "substantive ultra vires", delegated legislation is deemed void because it goes beyond the powers defined in the parent act. In "procedural ultra vires", delegated legislation is deemed void because of some procedural deficiency. A court may also quash delegated legislation on the basis of unreasonableness. |
Delegated legislation in the United Kingdom | See also | See also
Statutory Instrument Practice, 3rd edition (June 2003), Cabinet Office and His Majesty's Stationery Office
House of Commons Information Office Factsheet L7 - Statutory Instruments |
Delegated legislation in the United Kingdom | References | References
Category:Laws in the United Kingdom
Category:United Kingdom administrative law |
Delegated legislation in the United Kingdom | Table of Content | Short description, Background, Types, Church of England instruments, Crown Dependencies, Layout of official documents, Controls, See also, References |
Philadelphia History Museum | Use mdy dates | The Philadelphia History Museum was a public history museum located in Center City, Philadelphia from 1938 until 2018. From 1938 until 2010, the museum was known as the Atwater Kent Museum. The museum occupied architect John Haviland's landmark Greek Revival structure built in 1824–1826 for the Franklin Institute. The Museum operated as a city agency as part of Philadelphia's Department of Recreation. The building was listed on the National Register of Historic Places on August 1, 1979. |
Philadelphia History Museum | History | History
The museum was established through the efforts of Philadelphia Mayor S. Davis Wilson, Frances Wistar, president of the Philadelphia Society for the Preservation of Landmarks, and A. Atwater Kent, radio pioneer and inventor. In 1938 Kent purchased the former Franklin Institute building, which the Institute had vacated in 1933,, p.36 and gifted the building to the city for use as a public history museum. Following renovations carried out by the Works Progress Administration, the Museum opened in 1941.
After years of declining attendance and financial shortfalls, the museum closed its doors in 2018. In September 2019, the city approved a plan to transfer the museum's collections to Drexel University who would preserve the collections and offer them out for loan. Drexel was granted control of the collection in April 2022.
Drexel University has reverted the name of the collection to refer to Atwater Kent as the Atwater Kent Collection at Drexel. |
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