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Project

1-Wire Weather Station

The weather station in this project is quite basic, measuring only temperature, pressure, and humidity, but it may be easily expanded to measure other weather components, such as wind speed and rainfall. The design is based on using a series of…

Project

3x3x3 LED Cube

LEDs (light-emitting diodes) are rectifying semiconductor devices that convert electrical energy into electromagnetic radiation. You can use these devices to create a 3-dimensional light display. LED cubes require some care and good soldering skills…

Project

Chatbot, an Artificially Intelligent Microcontroller

The term "Chatbot" is used for a computer or computer program that is made to emulate some form of human intelligence through conversation. In this project, you will learn how easy it is to make a specific microcontroller—an Arduino™ Uno—seem as…

Project

Text-Controlled RGB LED

A red, green, and blue (RGB) light-emitting diode (LED) is a useful electronic component that can produce visible light in a variety of colors. This is done by varying the intensity of the light output of the three different color LED elements (red,…

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from article Electric filter

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from article Electric filter

Passive, lumped-element filters. (a) RC low-pass filter. (b) LC band-pass filter.

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from article Electric filter

Ladder structure. (a) Overall structure with alternating series and shunt arms. (b) LC circuit whose impedance contains both a finite-frequency pole and a zero. Such circuits are used in the series and shunt arms of the ladder structure.

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from article Electric filter

Mechanical filter.

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from article Electric filter

Single-amplifier filters. (a) Low-pass Sallen-Key filter. (b) Low-pass, infinite-gain, single-amplifier filter. (c) Cascade of second-order filter realizations.

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from article Electric filter

Multiple-amplifier filters. (a) State-variable (KHN) filter. (b) Tow-Thomas filter.

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from article Electric filter

Simulated-inductor realization of fifth-order high-pass filter. (a) RLC prototype, normalized for cutoff frequency of 1 rad/s (0.159 Hz). (b) Direct active-RC realization.

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from article Satellite television broadcasting

Direct broadcasting television satellite system.

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from article Genetically modified organism (GMO)

Transgenic zebrafish cells. Green fluorescent protein (GFP) is a fluorescent protein first discovered in the jellyfish Aequorea victoria. GFP is commonly used as a reporter of gene expression in other species. Here, GFP is expressed by zebrafish…

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from article Genetically modified organism (GMO)

Genome editing technologies. In particular, targeted nucleases are a powerful tool for precise genome editing in GMOs. Among these tools are (a) transcription activator-like effector nucleases (TALENs), (b) zinc-finger proteins (ZFPs), (c) homing…

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from article Modeling language

Systems engineering work space.

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from article Modeling language

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from article Modeling language

Component diagram for car window control. The small rectangles signify that this is a component diagram.

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from article Modeling language

Example of deep dependency structure.

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from article Telemetering

Functions of a generic aerospace telemetry system.

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from article Telemetering

Functions of a supervisory control and data acquisition (SCADA) system.

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from article Telemetering

Functions of a spacecraft telemetry and command system, using packet telemetry.

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from article Web 2.0

Web 2.0 encourages Internet users to actively participate as contributors and to help customize the media and technology as they see fit either for their own purposes or for the benefit of the Web community in which they participate. (Credit:…

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from article Matched-field processing

Plane-wave signal incident on a linear sensor array without any reflections. (a) Signal and sensor-array geometry. (b) Typical plane-wave array-signal-processor output, A(θ), and the matched-field processing output, B(θ), versus signal incident…

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from article Matched-field processing

Plane-wave signal incident on a linear sensor array with one reflection. (a) Signal and sensor-array geometry. (b) Typical plane-wave array-signal-processor output, A(θ), and the matched-field processing output, B(θ), versus signal incident angle, θ.

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from article Matched-field processing

Signals from a remote source incident on a linear sensor array in a waveguide with two reflecting surfaces and four signal paths connecting the source and the array. (a) Signal and sensor-array geometry. (b) Typical plane-wave array-signal-processor…

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from article Neandertal DNA

The geographical range within which Neandertal remains have been found (dashed line). White dots show the sites of the discoveries used to estimate the almost-complete hypervariable segment I (HVS-I) sequence of the Neandertal mtDNA. The approximate…

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from article Neandertal DNA

The mtDNA hypervariable segment I (HVS-I) diversity found in eight Neandertals. The nucleotide substitutions and insertions relative to the Cambridge Reference Sequence (CRS) are shaded. (Credit: Igor Ovchinnikov and William Goodwin)

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from article Neandertal DNA

Phylogenetic analysis of the Neandertal mtDNA hypervariable segment I (HVS-I) sequence. (a) Neighbor-joining tree of the Neandertal mtDNA sequences and 2500 modern human HVS-I sequences from 43 modern populations. (b) Neighbor-joining tree of the…

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from article Moving-target indication

Diagram of radar system with moving-target indication.

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from article Amplitude-modulation radio

An example of a low-frequency broadcast antenna. This three-tower array is connected to the Beidweiler long-wave transmitter (located in Beidweiler, Luxembourg), which broadcasts at a frequency of 234 kHz. Each tower is 290 m (951 ft) tall. (Photo…

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from article Philosophy of science

Pulpit Rock Park in Colorado Springs, Colorado, photographed with camera equipment sensitive to infrared wavelengths of light outside of the visible portion of the electromagnetic spectrum that humans can perceive. The "invisible" light is rendered…

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from article Philosophy of science

Bust of the Greek polymath Aristotle. (Credit: Photos.com/Getty Images)

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from article Frequency-modulation radio

Modulated waveforms.

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from article Frequency-modulation radio

FM subcarrier services.

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from article Frequency-modulation radio

IBOC digital radio signal (FM hybrid).

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from article Bioinformatics

Bioinformatics (indicated by the star in the diagram) is a scientific discipline that combines biology, mathematics, and computer science. It applies the power of computer processing to the study of biological systems. (Copyright © McGraw Hill)

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from article Bioinformatics

The central dogma of molecular biology explains how genetic material is transcribed into RNA, which is translated into proteins; then, proteins function to create metabolites, which affect the phenotypes of cells, tissues, and organisms. Scientists…

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from article Cellphone camera

The Samsung Galaxy S10’s three rear cameras. From left to right: 12-MP telephoto camera, f/2.4 aperture; 12-MP wide-angle camera, dual f/1.5 and f/2.4 aperture; and 16-MP ultrawide camera, f/2.2 aperture.

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from article Cellphone camera

Photograph taken with the iPhone XR’s single, rear 12-MP wide-angle camera with an f/1.8 aperture, 5X digital zoom, six-element lens system, autofocus with focus pixels, optical image stabilization, out-of-focus background (bokeh) and depth control,…

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from article Cellphone camera

The Bayer filter, invented by Brice Bayer of Eastman Kodak, overlays the camera image sensor grid to permit the measurement of color by the individual photo sensors. The data are analyzed to provide a color photograph. (a) Top view of the Bayer…

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from article Computer-system evaluation

Taxonomy of performance models.

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from article Neandertals

Neandertal cranium excavated from Forbes' Quarry, Gibraltar. Note the pronounced brow ridges, large braincase, and receding forehead. (Credit: Clive Finlayson/Gibraltar Museum)

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from article Neandertals

Gorham's Cave, Gibraltar, is the last known site of Neandertal occupation, being dated possibly to 30,000 years ago. (Credit: Clive Finlayson/Gibraltar Museum)

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from article Neandertals

Reconstructed skull of a Neandertal from the cave at La Chapelle-aux-Saints, France. (Credit: Illustration adapted from an original drawing by M. F. Ashley Montagu)

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from article Prehistoric technology

Elements of stone flaking. (a) Relationship between the core and the flake. (b) Major feature of the ventral or release surface of the flake. (After I. Tattersall, E. Delson, and J. A. Van Couvering, eds., Encyclopedia of Human Evolution and…

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from article Prehistoric technology

Principal techniques of stone-tool manufacture. (a) Hard-hammer, with free-hand percussion. (b) Anvil technique. (c) Bipolar technique. (d) Soft-hammer percussion. (e) Indirect percussion or punch technique. (f) Pressure flaking. (After…

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from article Prehistoric technology

Potters from the village of Harappa, Pakistan, display their wares in front of a replica of a two-chambered kiln used by ancient potters in the Indus Valley civilization. (Photo courtesy of R. P. Wright)

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from article Cellular automata