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Power Block
The Puretic power block is a special kind of mechanised winch used to haul nets on fishing vessels. The power block is a large pulley of aluminium with a hard rubber-coated Sheave (mechanical), sheave. While many men were needed for the back-breaking work of hauling a purse seine manually, the same work could be done by fewer men with a power block.Schmidt PG (1959) "The Puretic power block and its effect on modern purse seining". I''Modern Fishing Gear Of The World 1'' pp. 400–414. Editor Hilmar Kristjohsson, FAO, Rome. The Puretic power block revolutionized the technology of hauling fishing nets, particularly purse seine nets. According to the FAO, Food and Agriculture Organization of the United Nations (FAO), "no single invention has contributed more to the success of purse seine net hauling" than the power block, which was "the linch-pin in the mechanization of purse seining".FAO: Fishing EquipmentPower block Rome. Retrieved 28 May 2009. History The power block was invente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maritime Geography
Maritime geography is a collection of terms used by Navy, naval military units to loosely define three maritime regions: brown water, green water, and blue water. Definitions The elements of maritime geography are loosely defined and their meanings have changed throughout history. The USA's 2010 Naval Operations Concept defines blue water as "the open ocean", green water as "coastal waters, ports and harbors", and brown water as "navigable rivers and their estuaries". Robert Rubel of the US Naval War College includes bays in his definition of brown water, and in the past US military commentators have extended brown water out to from shore. During the Cold War, green water denoted those areas of ocean in which naval forces might encounter land-based aircraft and brown water, land-based artillery. The development of long-range bombers with antiship missiles turned most of the oceans to "green" and the term all but disappeared. After the Cold War, US Amphibious warfare, amphibious t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: ''passive'' sonar means listening for the sound made by vessels; ''active'' sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and sodar (an upward-looking in-air sonar) is used for atmospheric investigations. The term ''sonar'' is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low ( infrasonic) to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish And Fisheries
Sir Alister Clavering Hardy (10 February 1896 – 22 May 1985) was a British marine biologist, an expert on marine ecosystems spanning organisms from zooplankton to whales. He had the artistic skill to illustrate his books with his own drawings, maps, diagrams, and paintings. Hardy served as zoologist on the RRS ''Discovery''s voyage to explore the Antarctic between 1925 and 1927. On the voyage he invented the Continuous Plankton Recorder; it enabled any ship to collect plankton samples during an ordinary voyage. After retiring from his academic work, Hardy founded the Religious Experience Research Centre in 1969; he won the Templeton Prize for this in 1985. ''Camoufleur'' and artist Hardy was born in Nottingham, the son of Richard Hardy, an architect, and his wife, Elizabeth Hannah Clavering. He was educated not far away at Oundle School. He had intended to go to Oxford University in 1914, but on the outbreak of war he instead volunteered for the army, and was made a ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Wiley & Sons, Inc
John Wiley & Sons, Inc., commonly known as Wiley (), is an American multinational publishing company that focuses on academic publishing and instructional materials. The company was founded in 1807 and produces books, journals, and encyclopedias, in print and electronically, as well as online products and services, training materials, and educational materials for undergraduate, graduate, and continuing education students. History The company was established in 1807 when Charles Wiley opened a print shop in Manhattan. The company was the publisher of 19th century American literary figures like James Fenimore Cooper, Washington Irving, Herman Melville, and Edgar Allan Poe, as well as of legal, religious, and other non-fiction titles. The firm took its current name in 1865. Wiley later shifted its focus to scientific, technical, and engineering subject areas, abandoning its literary interests. Wiley's son John (born in Flatbush, New York, October 4, 1808; died in East O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Policy
''Marine Policy'' is a monthly interdisciplinary peer-reviewed academic journal published by Elsevier concerning ocean policy studies, analyzing social science disciplines relevant to the formulation of marine policy. It was established in 1977 by founding editor Tony Loftas. The current editor-in-chief is Sebastián Villasante ( University of Santiago de Compostela). Abstracting and indexing According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 3.5. See also * List of international relations journals The following list of scholarly journals in international relations contains notable English-language academic journals on international relations. It is not comprehensive, as there are hundreds currently published. Popular magazines or other publi ... References External links * {{DEFAULTSORT:Marine Policy Elsevier academic journals English-language journals International relations journals Monthly journals Academic journals esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier BV
Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', '' Cell'', the ScienceDirect collection of electronic journals, '' Trends'', the '' Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services include digital tools for data management, instruction, research analytics, and assessment. Elsevier is part of the RELX Group, known until 2015 as Reed Elsevier, a publicly traded company. According to RELX reports, in 2022 Elsevier published more than 600,000 articles annually in over 2,800 journals. As of 2018, its archives contained over 17 million documents and 40,000 e-books, with over one billion annual downloads. Researchers have criticized Elsevier for its high profit margins a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labour Demand
In economics, the labor demand of an employer is the number of labor-hours that the employer is willing to hire based on the various exogenous (externally determined) variables it is faced with, such as the wage rate, the unit cost of capital, the market-determined selling price of its output, etc. The function specifying the quantity of labor that would be demanded at any of various possible values of these exogenous variables is called the labor demand function. The sum of the labor-hours demanded by all employers in total is the market demand for labor. Perfect competitor The long-run labor demand function of a competitive firm is determined by the following profit maximization problem: : \text \,\, pQ - wL - rK \,\, \text \,\, Q, \, L, \, \text \, K : \text :Q = f\,(L, K), where ''p'' is the exogenous selling price of the produced output, ''Q'' is the chosen quantity of output to be produced per month, ''w'' is the hourly wage rate paid to a worker, ''L'' is the number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Five-dollar Note
The Canadian five-dollar note is the lowest denomination and one of the most common banknotes of the Canadian dollar. As with all modern Canadian banknotes, all text is in both English and French . Frontier series note The most recent Canadian five-dollar note, part of the Frontier series, is predominantly blue and was introduced 7 November 2013, using the same technology found in the other notes of that series. The bill features a portrait of Canada's seventh prime minister, Wilfrid Laurier, and a hologram of the Mackenzie Tower from the West Block on Parliament Hill on the front; the back features an astronaut working with Dextre attached to the Canadarm2. This note features raised, textured printing as well as a special tactile feature (similar to Braille dots) to assist the blind in identifying the denomination. Security features include "Bank of Canada" and "" visible only under ultraviolet light, and yellow dots representing the EURion constellation on the reverse sid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Menhaden
Menhaden, also known as mossbunker, bunker, and "the most important fish in the sea", are forage fish of the genera ''Brevoortia'' and ''Ethmidium'', two genera of marine fish in the order Clupeiformes. ''Menhaden'' is a blend of ''poghaden'' (''pogy'' for short) and an Eastern Algonquian languages, Algonquian word akin to Narragansett language, Narragansett ''munnawhatteaûg'', derived from ''munnohquohteau'' ("he fertilizes"), referring to their use of the fish as fertilizer. It is generally thought that Pilgrims (Plymouth Colony), Pilgrims were advised by Tisquantum (also known as Squanto) to plant menhaden with their crops. Description Menhaden are flat and have soft flesh and a deeply forked tail. They rarely exceed in length, and have a varied weight range. Gulf menhaden and Atlantic menhaden are small oily-fleshed fish, bright silver, and characterized by a series of smaller spots behind the main humeral spot. They tend to have larger scales than yellowfin menhaden and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anchovy
An anchovy is a small, common forage fish of the Family (biology), family Engraulidae. Most species are found in marine waters, but several will enter brackish water, and some in South America are restricted to fresh water. More than 140 species are placed in 16 genera; they are found in the Atlantic, Indian and Pacific Oceans, and in the Black Sea and the Mediterranean Sea. Anchovies are usually classified as oily fish. Taxonomy Anchovies are classified into two subfamilies and 16 genera: * Superfamily Engrauloidea ** Genus †''Clupeopsis'' Casier, 1946 ** Genus †''Monosmilus'' Capobianco et al, 2020 ** Family Engraulidae Theodore Gill, Gill, 1861 *** Subfamily Engraulinae Theodore Gill, Gill, 1861 **** Genus ''Amazonsprattus'' Tyson R. Roberts, Roberts, 1984 **** Genus ''Anchoa'' David Starr Jordan, D. S. Jordan & Barton Warren Evermann, Evermann, 1927 **** Genus ''Anchovia'' D. S. Jordan & Evermann, 1895 **** Genus ''Anchoviella'' Henry Weed Fowler, Fowler, 1911 **** G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sardine
Sardine and pilchard are common names for various species of small, oily forage fish in the herring suborder Clupeoidei. The term "sardine" was first used in English during the early 15th century; a somewhat dubious etymology says it comes from the Italian island of Sardinia, around which sardines were once supposedly abundant. The terms "sardine" and "pilchard" are not precise, and what is meant depends on the region. The United Kingdom's Sea Fish Industry Authority, for example, classifies sardines as young pilchards. One criterion suggests fish shorter in length than are sardines, and larger fish are pilchards. The FAO/ WHO Codex standard for canned sardines cites 21 species that may be classed as sardines. FishBase, a database of information about fish, calls at least six species pilchards, over a dozen just sardines, and many more with the two basic names qualified by various adjectives. Etymology The word ''sardine'' first appeared in English in the 15th cen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmon
Salmon (; : salmon) are any of several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the genera ''Salmo'' and ''Oncorhynchus'' of the family (biology), family Salmonidae, native to tributary, tributaries of the North Atlantic (''Salmo'') and North Pacific (''Oncorhynchus'') basins. ''Salmon'' is a colloquial or common name used for fish in this group, but is not a scientific name. Other closely related fish in the same family include trout, Salvelinus, char, Thymallus, grayling, Freshwater whitefish, whitefish, lenok and Hucho, taimen, all coldwater fish of the subarctic and cooler temperate regions with some sporadic endorheic populations in Central Asia. Salmon are typically fish migration, anadromous: they hatch in the shallow gravel stream bed, beds of freshwater headstreams and spend their juvenile fish, juvenile years in rivers, lakes and freshwater wetlands, migrate to the ocean as adults and live like sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
