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Interstellar travel

Interstellar space travel is manned or unmanned travel between stars. Interstellar travel is much more difficult than travel within the Solar System, though travel in starships is a staple of science fiction. Actually, there is no suitable techno ...

Mechanism

A mechanism is a mechanical device for doing something. It includes the idea of tools and machines, but is used for a wider range of objects, processes and ideas. Palaeolithic hand axes were one of the first tools used. Simple modern mechanisms w ...

National Academy of Engineering

United States National Academy of Engineering, a private, non-profit institution that was founded in 1964. Election to the NAE is considered the highest achievement in engineering-related fields and often comes as a recognition of a lifetimes wor ...

National Research Council

National Research Council of USA is the working arm of United States National Academies, carrying out most of the studies done in their names. The National Research Council was organized in 1916 in response to the increased need for scientific an ...

Negative feedback

Negative feedback is a basic concept of cybernetics; it is the basis of regulation and control. It is important in engineering and physiology. In biology and physiology negative feedback is known as homeostasis. Negative feedback occurs when the ...

Nuclear engineering

Nuclear engineering is a field of engineering dealing with application of atomic nuclei breakdown and other sub-atomic physics, based on the principles of nuclear physics. It includes the interaction and maintenance of nuclear fission systems and ...

Packaged terminal air conditioner

A packaged terminal air conditioner is a kind of self-contained heating and air conditioning system. It is commonly found in hotels, motels, senior housing facilities, hospitals, condominiums, apartment buildings, add-on rooms & sunrooms. Many PT ...

Pelton wheel

The pelton wheel is a kind of water turbine. It is used in power plants, to convert a water flow into a movement of a wheel. Lester Alan Pelton invented it in the 1870s. In a regular wheel for example of a mill, the energy is obtained from the we ...

Perpetual motion

Perpetual motion refers to a movement that goes on forever once started without additional energy added. A machine that could be set in motion once would continue to move forever. Such a device or system would be against the law of conservation o ...

Pipe (material)

A pipe is a tube or hollow cylinder for the transport of fluid. The terms pipe and tube can be used for the same objects. Pipe is generally specified by the internal diameter whereas tube is usually defined by the outside diameter but may be spec ...

Plans (drawings)

Plans are a set of two-dimensional diagrams or drawings used to describe a place or object, or to communicate building or fabrication instructions. Usually plans are drawn or printed on paper, but they can take the form of a digital file.

Power consumption

In electrical engineering, power consumption refers to the electrical energy per unit time, supplied to operate something, such as a home appliance. Power consumption is usually measured in units of watts or kilowatts. The energy used by equipmen ...

Resilience

Resilience generally means the ability to recover from some shock or disturbance. There are different meanings for resilience in psychology: the mental ability to recover quickly from depression, illness or misfortune resilience of a system: the ...

Second moment of area

The moment of force about any point is the product of the force and perpendicular distance between them. If this first moment is again multiplied by the perpendicular distance between them, the product so obtained is called the second moment of f ...

Software engineering

Software engineering is a field of engineering, for designing and writing programs for computers or other electronic devices. A software engineer, or programmer, writes software and compiles software using methods that improve it. Better quality ...

Soil classification

Soil classification means that one finds categories of soils that are based on general characteristics as well as criteria that decide about the use that is possible. Soil classification can be approached from both the perspective of pedogenesis ...

Spoke

A spoke is one of several rods radiating from the center of a wheel, connecting the hub with the round traction surface. The term originally meant the portions of a log which one had split lengthwise into four or six sections. The radial members ...

Spring (device)

A spring is a device typically made of metal, usually steel. The metal can be compressed squeezed. When the compression force is removed, the spring returns to its original length. The metal is usually spring steel, and it is wound tightly. There ...

Stress (mechanics)

Stress is the force per unit area on a body that tends to cause it to change shape. Stress is a measure of the internal forces in a body between its particles. These internal forces are a reaction to the external forces applied on the body that c ...

Structural engineering

Structural engineering is a subset of civil engineering dealing with the design and analysis of buildings and large non-building structures to withstand both the gravity and wind loads as well as natural disasters. Besides, it may also cover desi ...

Structural load

Structural loads or actions are forces, deformations, or accelerations applied to a structure or its components. A load is the amount of weight a structure has to carry. Loads cause stresses, deformations, and displacements in structures. Structu ...

Structural pipe fitting

Structural pipe fitting is a pipe used for various structures. A Structural pipe fitting, also known as a slip on pipe fitting, clamp or pipe clamp is used to build structures such as handrails, guardrails, and other types of pipe or tubular stru ...

Suspension (vehicle)

Suspension is the term given to the system of springs, shock absorbers and linkages. The suspension acts as an intermediate between the car and the road and solves several problems: Ensures acceptable running smoothness, compensates for uneven pa ...

Thermal efficiency

The thermal efficiency is a dimensionless performance measure of a thermal device such as an internal combustion engine, a boiler, or a furnace, for example. The input, Q i n {\displaystyle Q_{in}\,}, to the device is heat, or the heat-content of ...

Torque

In physics, torque is the tendency of a force to turn or twist. If a force is used to begin to spin an object, or to stop an object from spinning, a torque is made. The force applied to a lever, multiplied by the distance from the levers fulcrum, ...

Torque converter

A torque converter, or torque multiplier, is a device for multiplying torque. It is widely used in transmission systems for road and rail vehicles with internal combustion engines.

Transmission

In mechanics, a transmission or gearbox means gears working together. The most common transmission is the transmission in a car. In a car, the engine makes the crankshaft spin. The crankshaft makes the transmissions gears spin, which spin some mo ...

Turbine

A turbine is an engine that turns fluid movement into energy. Simple turbines have a shaft with a blade on it. Moving fluids, such as water or air, push the blades so that they turn around with the shaft. The turning movement is most often used t ...

Two-wheel drive

Two-wheel drive describes vehicles in which, in theory, two wheels receive power from the engine at the same time. Usually the two wheels are on the same axle in the drivetrain. Most vehicles with two-wheel drive are mainly for use on roads and h ...

Water supply system

A water supply system or water supply network is an engineering system which provides a supply of water. A water supply system typically includes: Water pressurizing by such as pumping stations are usually needed at the outlet of underground or a ...

Wind engineering

Wind engineering studies effects of wind on the buildings and its possible damage or problems to their inhabitants. From the point of structural engineering, it is interested in strong winds, which may cause discomfort, as well as extreme winds, ...

Ethnography

Ethnography is a kind of anthropology. Ethnographers study specific cultures. Ethnography mostly uses participant observation. The researcher becomes part of the setting or mixes with the people being studied. They try to record patterns of socia ...

Auto-ethnography

Auto-ethnography is a method of social research whose defining characteristic is that the author links personal experience and autobiography with social, political, and cultural concepts. Its difference from ethnography is the high degree of subj ...

Bronislaw Malinowski

Bronislaw Malinowski was a well known British sociocultural anthropologist. He is most famous for his work on the Trobriand Islands, creating a formal ethnographic process, and for coming up with the idea of functionalism.

Participant observation

Participant observation is a way of getting information about a group of people. A person doing participant observation will live with a group of people in their normal environment. They do this so they can learn about that groups way of life. On ...

Forensic science

Forensic science is when different fields of science work together to answer the questions a lawyer would ask. Most often, forensics is about proving that someone was present at a place where a crime was committed. Specialists take samples which ...

Autopsy

An autopsy is a medical examination of a corpse to find out what killed it. Autopsies are done by specialised doctors, called pathologists. Autopsies are not done all the time. They are usually done either for medical reasons, for legal ones. One ...

Digital forensics

Digital forensics is a forensic science where experts look at computer devices to help solve crime. It can also include mobile phones. The experts who do digital forensics are often called "analysts" or "investigators". When an expert is asked to ...

Footprint

Footprints are shapes on the ground where people or animals walked. The foot touches the ground and at that position a footprint appears afterwards. This can happen because the ground is muddy or snowy and the foot sinks a little bit into the gro ...

Forensic anthropology

Forensic anthropology is the analysis of human remains for the purpose of solving criminal cases and identifying the cause of death. In order to understand the death of a person, forensic anthropologists collect information from their bones. Fore ...

Forensic psychology

Forensic psychology is a branch of psychology which relates to the law. The main part of forensic psychology is working with the criminal justice system. Forensic psychology is the use of psychological practices and principles and applying them t ...

Gunshot residue

Gunshot residue is one of the results of firing a gun. When a bullet leaves the barrel of a firearm, it is accompanied by gases that include both burned and unburned particles of gunpowder. It also includes traces of metal from the firearm, the a ...

History of science

The history of science is the study of the historical development of science and scientific knowledge. The English word scientist is relatively recent – first coined by William Whewell in the 19th century. Previously, people investigating nature ...

Age of the Earth

The age of the Earth is estimated at a little over 4.5 billion years. Working this out was a difficult problem to solve. For most of human history, the basic facts about the planet were unknown. The problem was tackled by Earth scientists in the ...

Catastrophism

Catastrophism is the idea that Earth has been affected in the past by sudden, short-lived, violent events. Catastrophes, possibly worldwide in scope, came between long periods of quiet inactivity. This was called catastrophism by William Whewell ...

Classical element

The Greek classical elements are fire, air, water, and earth. In Greek philosophy, science and medicine, these make up a whole. Fire is both hot and dry. Water is both cold and wet. Air is both hot and wet. Earth is both cold and dry. The image b ...

Edward Drinker Cope

Edward Drinker Cope was an American biologist. He was notable for his work on fossil animals of North America. Cope was born in Philadelphia, Pennsylvania. Cope was a paleontologist, comparative anatomist, herpetologist and ichthyologist. He wrot ...

Discovery (observation)

Discovery is the act of detecting something new, or something "old" that had been unknown. In science and academic disciplines, discovery is the observation of new phenomena. It is discovery of new actions, or new events. It provides new reasonin ...

Invisible College

The Invisible College was the name given to themselves by a group of like-minded scientists and natural philosophers in England in the mid-17th century. The informal association is considered to have been one of the origins of the Royal Society. ...

Luminiferous aether

Luminiferous aether is a substance once believed to fill the Universe and explain how the transmission of waves of light can happen. People believed that light was a kind of wave. Waves travel over the surface of water in a pond, through the air ...

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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!

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