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Helicopter Logging
Heli-logging, or helicopter logging, is a method of logging that uses helicopters to remove cut trees from forests by lifting them on cables attached to a helicopter. Helicopter logging is often used in inaccessible areas of forests. Because the use of helicopters reduces the level of infrastructure required to log in a specific location, the method also helps to reduce the environmental impact of logging. It also can increase the productivity in these remote areas. History Process Heli-logging is also known as standing stem harvesting, which is based on individual tree selection (ITS).Cleaver, D. 2001Standing Stem Harvesting The International Mountain Logging and 11th Pacific Northwest Skyline Symposium 2001, 280-284. The selection process is done by engineers and surveyors. The trees are selected based on demand for specific types and grades. Before the selection process is complete, the selected trees are bored to check their reliability. The selected trees are then marke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logging The Town Belt, Wellington 18 April 2005 02
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucks or flatcar#Skeleton car, skeleton cars. Logging is the beginning of a supply chain that provides raw material for many products societies worldwide use for housing, construction, energy, and consumer paper products. Logging systems are also used to manage forests, reduce the risk of wildfires, and restore ecosystem functions, though their efficiency for these purposes has been challenged. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities. Illegal logging refers to the harvester (forestry), harvesting, transportation, purchase, or sale of timb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felled Tree
Lumber is wood that has been processed into dimensional lumber, including beams and planks or boards, a stage in the process of wood production. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, window frames). Lumber has many uses beyond home building. Lumber is sometimes referred to as timber as an archaic term and still in England, while in most parts of the world (especially the United States and Canada) the term timber refers specifically to unprocessed wood fiber, such as cut logs or standing trees that have yet to be cut. Lumber may be supplied either rough- sawn, or surfaced on one or more of its faces. Beside pulpwood, ''rough lumber'' is the raw material for furniture-making, and manufacture of other items requiring cutting and shaping. It is available in many species, including hardwoods and softwoods, such as white pine and red pine, because of their low cost. ''Finished lumber'' is supplied in standard sizes, mostl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopters
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most common h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ScienceDirect
ScienceDirect is a website which provides access to a large bibliographic database of scientific and medical publications of the Dutch publisher Elsevier. It hosts over 18 million pieces of content from more than 4,000 academic journals and 30,000 e-books of this publisher. The access to the full-text requires subscription, while the bibliographic metadata is free to read. ScienceDirect is operated by Elsevier. It was launched in March 1997. Usage The journals are grouped into four main sections: ''Physical Sciences and Engineering'', ''Life Sciences'', ''Health Sciences'', and ''Social Sciences and Humanities''. Article abstracts are freely available, and access to their full texts (in PDF and, for newer publications, also HTML) generally requires a subscription or pay-per-view purchase unless the content is freely available in open access. Subscriptions to the overall offering hosted on ScienceDirect, rather than to specific titles it carries, are usually acquired through a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomorphology (journal)
''Geomorphology'' is a peer-reviewed scientific journal about geomorphology Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or n .... External links * Earth and atmospheric sciences journals Elsevier academic journals English-language journals Geomorphology journals {{Geomorphology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landslides
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Causes Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This is essentially due to a decrease in the shear strength of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utilities
A public utility company (usually just utility) is an organization that maintains the infrastructure for a public service (often also providing a service using that infrastructure). Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies. Public utilities are meant to supply goods/services that are considered essential; water, gas, electricity, telephone, and other communication systems represent much of the public utility market. The transmission lines used in the transportation of electricity, or natural gas pipelines, have natural monopoly characteristics. If the infrastructure already exists in a given area, minimal benefit is gained through competing. In other words, these industries are characterized by ''economies of scale'' in production. There are many different types of public utilities. Some, especially large companies, offer multiple products, such as electricity and natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loggers
Lumberjacks are mostly North American workers in the logging industry who perform the initial harvesting and transport of trees for ultimate processing into forest products. The term usually refers to loggers in the era (before 1945 in the United States) when trees were felled using hand tools and dragged by oxen to rivers. The work was difficult, dangerous, intermittent, low-paying, and involved living in primitive conditions. However, the men built a traditional culture that celebrated strength, masculinity, confrontation with danger, and resistance to modernization. Terminology The term lumberjack is of Canadian derivation. The first attested use of the word comes from an 1831 letter to the ''Cobourg Star and General Advertiser'' in the following passage: "my misfortunes have been brought upon me chiefly by an incorrigible, though perhaps useful, race of mortals called lumberjacks, whom, however, I would name the Cossack's of Upper Canada, who, having been reared among th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-64 Skycrane
The Sikorsky S-64 Skycrane is an American twin-engine heavy-lift helicopter. It is the civil version of the United States Army's CH-54 Tarhe. It is currently produced as the S-64 Aircrane by Erickson Inc. Development Under Sikorsky The Sikorsky S-64 was designed as an enlarged version of the prototype ''flying crane'' helicopter, the Sikorsky S-60. The S-64 had a six-blade main rotor and was powered by two Pratt & Whitney JFTD12A turboshaft engines. The prototype S-64 first flew on 9 May 1962 and was followed by two further examples for evaluation by the German armed forces. The Germans did not place an order, but the United States Army placed an initial order for six S-64A helicopters (with the designation YCH-54A Tarhe). Seven S-64E variants were built by Sikorsky for the civil market. Under Erickson Originally a Sikorsky Aircraft product, the type certificate and manufacturing rights were purchased from them by Erickson Air-Crane in 1992. Since that time, Erick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volumes
Volume is a measure of occupied three-dimensional space. It is often quantified numerically using SI derived units (such as the cubic metre and litre) or by various imperial or US customary units (such as the gallon, quart, cubic inch). The definition of length (cubed) is interrelated with volume. The volume of a container is generally understood to be the capacity of the container; i.e., the amount of fluid (gas or liquid) that the container could hold, rather than the amount of space the container itself displaces. In ancient times, volume is measured using similar-shaped natural containers and later on, standardized containers. Some simple three-dimensional shapes can have its volume easily calculated using arithmetic formulas. Volumes of more complicated shapes can be calculated with integral calculus if a formula exists for the shape's boundary. Zero-, one- and two-dimensional objects have no volume; in fourth and higher dimensions, an analogous concept to the normal volu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Database
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spans formal techniques and practical considerations, including data modeling, efficient data representation and storage, query languages, security and privacy of sensitive data, and distributed computing issues, including supporting concurrent access and fault tolerance. A database management system (DBMS) is the software that interacts with end users, applications, and the database itself to capture and analyze the data. The DBMS software additionally encompasses the core facilities provided to administer the database. The sum total of the database, the DBMS and the associated applications can be referred to as a database system. Often the term "database" is also used loosely to refer to any of the DBMS, the database system or an appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
