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So I moulded and casted an improved cockpit from my vac-formed master, cleaned it up, and hey, not bad!
All credit for the electronics and programming work goes to my dad, who is just roughing out the sequencing for the micropython system. He assures me the modulation and frequency can be made a lot smoother, but these tests are just to understand what we're trying to acheive
Teisipäev, 14. aprill kell 19.30 ja 21.00
Kanuti Gildi SAAL (Pikk 20)
Pilet 10/7 eelmüügist, 12/7 enne kontserti
KAVAS:
“Rhythmus 21” (1921): Video Hans Richter, muusika Ove-Kuth Kadak (2015, esiettekanne) … 3’10”
“(üle)küllus” (2015, esiettekanne): Muusika ja video Aljona Kastjušina … 7’
“Controcorrente” (2012, Eesti esiettekanne): Muusika ja video Ivan Penov … 7’30″
“Phase Walk” (2015, esiettekanne): Henri Georg Viies … u 7’
“Cross modulation” (2015, esiettekanne): Muusika Ekke Västrik … 7’
“Ghosts and Whispers” (2014, Eesti esiettekanne): Muusika ja video Damiano Marconi … 6’30″
“Merkin” (2015, esiettekanne): Hendrik Tammjärv … u 7’
“Seppie senz’ossa” (2013, Eesti esiettekanne): Video Paolo Pachini, muusika Roberto Doati … 10’
“Rhythmus 21” (1921): Video Hans Richter, muusika Giovanni Tancredi (2015, esiettekanne) … 3’10”
Audiovisuaalsed kompositsioonid, versioon 1.2: visuaalne väljendus muusikalise mõtte laiendusena.
Eesti Muusika- ja Teatriakadeemia kompositsiooniosakonna audiovisuaalse kompositsiooni kontsert toob kokku selle valdkonna ajaloo olulise repertuaari ja EMTA audiovisuaalse kompositsiooni tudengite loomingu. Sel aastal esitleb EMTA muuhulgas rahvusvaheliselt tuntud heliloojate Paolo Pachini ja Roberto Doati audiovisuaalse kompositsiooni “Seppie senz’ossa” (2013) Eesti esiettekannet.
Kontserdi kunstiline juht on Paolo Girol.
Kestus: umbes 1 tund.
Saadaval piiratud hulk pileteid (kontsert kantakse ette kaks korda, igal kontserdil ainult 50 istekohta patjadel). Hilinejaid sisse ei lubata!
Koostöös Eesti Muusika- ja Teatriakadeemia kompositsiooniosakonna ja festivaliga “Saksa kevad”
Group 1_
Cynthia Castillo, Moises Talavera, Amir Hanna, Guillermo Perez, Osvaldo Andrade
Networked Fabrication for Urban Provocations.
Shifting Paradigms from Mass Production to Mass Customization
Computational architecture and design course
Conventional construction methods all depart from the basic premises of mass production: standardization, modulation and a production line. What these systems developed during the last two centuries fail to take into account are the evolutionary leaps and bounds the manufacturing industry has taken over the last decades. With the introduction of CNC technologies and rapid prototyping machines have altered the paradigms of fabrication forever. It is due to these new tools that it is now possible to create (n) amount of completely unique and different pieces with the same amount of energy and material that is required to create (n) identical pieces. The possibilities for implementation of new forms, textures, materials and languages are infinite due to the versatility that these new tools offer a growing network of architects, designers, fabricators that are integrating them into their professional practices to generate unique and precise objects that respond to countless data and real-life conditions.
Instructors:
Monika Wittig [ LaN, IaaC ]
Shane Salisbury [ LaN, IaaC ]
Filippo Moroni [ SOLIDO, Politecnico di Milano ]
MS Josh Updyke [ Advanced Manufacturing Institute, KSU, Protei ]
Aaron Gutiérrez Cortes [ Amorphica ]
We designed our buffers clean up your sound and allow the maximum tone from your pickups and cables to your amp. Low output impedance can send the signal through long cables without losing response and top frequencies. Not operable with battery.
Blacktron Gold - Listening and Assault Unit
Spacecraft equipped with:
- stereo cockpit
- optoechoic head
- white noise generator
- modulation metronome
- dual megabass cannon
- large aperture antenna with phrase scanning
- dual IR (iridium) jam-session-er
- powerful pro-tone torpedo
- dual frequency Hi-Fi-per sonic missiles
Jerusalem, Israel: In an outdoor, shopping-mall network of pedestrian streets, an art construction runs overhead like a canopy. It consists of a long series of closely spaced wires, strung with numerous, loosely hanging gold-colored tags. When contemplating this construction attentively, one notices a subtle modulation of light flowing through it continuously, back and forth, from end to end. It isn’t clear to me, however, whether this effect was created, simply, by gentle breezes flowing through the mall’s network of streets, or whether (the more likely case, in my estimation) it was electronically controlled.
(2/4)
Dolby demonstrated publicly for the first time its recently announced Dolby PRM-4200 Professional Reference Monitor. The world's first LCD-based video reference display that accurately reveals true and deep black levels with higher contrast across the entire color spectrum provides an unprecedented luminance range and level.
Scheduled for availability later this year, the 42-inch monitor was specifically designed for professionals who rely on the most accurate measurement tools for color-critical work. It uses a backlight comprised of red, green, and blue LEDs that are modulated individually on a frame-by-frame basis. The LCD panel is also modulated in real time as part of the dual-modulation process.
12 Interlocking Irregular Hyperboloidal Dodecahedra 360 units
In my hand.
Following an initial prototype with only a singular unit type which attempted a hexahedral symmetry analog of 30 Dodecahedra, I developed this more nuanced version, which has a different exterior weaving pattern and multiple paper proportions. However, as a constraint, I attempted to use only one pocket type for all of the units. This makes some vertices different than others in terms of the dihedral angles of the surrounding units, but the edges shafts are long enough to accommodate modulation between vertices without appreciable difficulty in most cases. This is constructed via scaffolding so that each dodecahedron represents one edge of a cube. The resulting compound is at the time of writing this, the largest interlocking origami cubic symmetry wireframe compound by unit count that I know of.
Designed by me.
Folded out of Cordenons’ Stardream paper.
about 0 to 100% duty cycle, up to 4kW (if used with not included heat-sinks), about 28kHz pulse width modulation frequency (PWM)
Stereo Viewer for all my photos: jongames.com/stereophoto/
Here, we've pretty much settled on curve of intensity change, but we wanted to see what it would look like where all the LEDs are always on at a low level, but pulsing to higher intensity.
This is all being done with pulse width modulation and an arduino.
Next step, more LEDs, brighter, with a wider view angle.
From Minas Gerais in Brazil comes this 4" wide specimen of optical calcite placed upon a reflective CD-R disc. A green laser beam is directed through the crystal in the direction shown by the arrow. Green laser light is scattered as it enters and exits the calcite. Within the calcite the laser beam stimulates red fluorescence likely due to manganese impurities.
The photo was taken through red laser goggles acting as a high Q magenta (green rejection) notch filter.
Contains:
Calcite (FL Orange Red >Green Laser) Act: Mn?
Shown under green laser light.
Series best viewed in Light Box mode using Right and Left arrows to navigate.
The Dirty Carter Electronic Sound Generating Instrument was designed by John Richards (Dirty Electronics) and Chris Carter from legendary Industrial pioneers Throbbing Gristle. It was produced for a special performance by Carter and the 25 strong Dirty Electronics Ensemble in 2010. It was originally designed as a touch controlled instrument with the player's skin resistance completing the circuit. This hard wired modification by A.S.M.O. gives more control and predictability by wiring all to the touch contacts to pots and switches. An additional low pass resonant filter has been added, LFO and an external CV socket for filter modulation.
The case is made of stained ply and the front panel is covered with black leatherette.
Backpanel: fuses.
Designed by Robert Moog in 1970, the Minimoog Model D synthesizer is still regarded as the Rolls Royce equivalent for analog keyboard-based synthesizers. Specifically designed for touring musicians, the minimoog exported electronic music experiments from university labs out to the masses - and her deep farting bass-sounds (think of Kraftwerk's Autobahn), lead and space bleeps and sweeps have become HUGELY popular over the last 38 years.
There were originally 13,000 minimoogs produced between 1970 and 1981. After a brief hiatus during the digital-synth craze in the 1980s, the minimoog enjoyed a resurgence of interest among musicians since the 1990s...and yes, it's becoming harder to get a hold on one.
I obtained this Mini from a studio garage sale back in 1989 for US$ 150 (in prime condition - save the crackling external input knob). After lying dormant for 7 years now, it's time to bring life back into this 1973 model D mini. Tropical humidity heavily damaged the furnishing. It needs re-tuning of the oscillators, cleaning of the electronic board, new switches for filter modulation, and thinking about a new base panel.
Title: Concha Renaissance San Juan Resort
Other title: Concha
Creator: Toro, Osvaldo 1914-1995; Ferrer, Miguel, 1915-2004; Salvadori, Mario George, 1907-1997; Marvel & Marchand Architects
Creator role: Architect
Date: 1958 (original) 2008 (renovation)
Current location: San Juan, Puerto Rico
Description of work: Renaissance Hotels tasked architect Jose R. Marchand and interior designer Jorge Rossello with renovating and saving this beachside landmark. "[B]y the mid-1990s the venerable La Concha hotel had been shuttered, abandoned and left to rot...Originally designed by Osvaldo Toro and Miguel Ferrer, with an eccentric but utterly loveable seashell-shaped restaurant by Mario Salvatori [sic], La Concha was a beautifully massed, expertly sited, vividly inventive building perfectly in sync with its time. Closely attuning the hotel to its sun-swept setting, the architects created deep-shading overhangs, open corridors, windows and doors that gave onto lush interior courtyards and provided cross ventilation, and beautifully lacy quiebra-sol (their take on a brise-soleil) for further modulation of the light and heat" (Frank, Michael. "La Concha Revival". Architectural Digest. Aug 2009, p. 103-104. Print).
Description of view: View of the south side of the hotel from the pool and lounge area located in the center of the hotel.
Work type: Architecture and Landscape
Style of work: Modern: International Style
Culture: Puerto Rican
Materials/Techniques: Concrete
Trees
Plants
Source: Pisciotta, Henry (copyright Henry Pisciotta)
Date photographed: May 13, 2008
Resource type: Image
File format: JPEG
Image size: 3072H X 2304W pixels
Permitted uses: This image is posted publicly for non-profit educational uses, excluding printed publication. Other uses are not permitted. For additional details see: alias.libraries.psu.edu/vius/copyright/publicrightsarch.htm
Collection: Worldwide Building and Landscape Pictures
Filename: WB2010-0273 Concha.JPG
Record ID: WB2010-0273
Sub collection: resorts
Copyright holder: Copyright Henry Pisciotta
about 0 to 100% duty cycle, up to 4kW (if used with not included heat-sinks), about 28kHz pulse width modulation frequency (PWM)
Stereo Viewer for all my photos: jongames.com/stereophoto/
My first QSL card from outside the United States. Hector lives in Cienfuegos, Cuba, 1149 miles from my location in Louisville, Kentucky.
QSO: www.flickr.com/photos/jmschneid/8556896541
Current callsign is KB4BB
Sarah Perkins | Springfield MO
"Pierced Container" (2010)
Sterling, copper, enamel
As a maker of hollowware, I use properties of the metal: the plasticity, the permanence and the dimensionality. As an enameler, I use properties of the glass: the preciousness, the surface qualities and the color. In my work these properties function together to make a whole, with the two materials complementing and completing each other, rather than one being visually more important than the other.
My work reflects my emotional response to my environment, often referring to landscape, body part or natural object. Some of the forms are based directly on plants, fruits, rock formations and other natural objects. The colors and enamel imagery are derived from natural objects as well because I find the natural modulations of color, texture and surface very appealing and very intimate.
Además de abreviación para Bogotá, bta es:
BlueTooth Address
Bluetooth is a wireless protocol for exchanging data over short distances from fixed and mobile devices, creating personal area networks (PANs). It was originally conceived as a wireless alternative to RS232 data cables. It can connect several devices, overcoming problems of synchronization.
Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 frequencies. In its basic mode, the modulation is Gaussian frequency-shift keying (GFSK). It can achieve a gross data rate of 1 Mb/s. Bluetooth provides a way to connect and exchange information between devices such as mobile phones, telephones, laptops, personal computers, printers, Global Positioning System (GPS) receivers, digital cameras, and video game consoles through a secure, globally unlicensed Industrial, Scientific, and Medical (ISM) 2.4 GHz short-range radio frequency bandwidth. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group (SIG). The Bluetooth SIG consists of companies in the areas of telecommunication, computing, networking, and consumer electronics
Listen: A Music and Video Experiment
Featured video art and experimental music throughout the Murphy Art Center -- including Alchemy in Suite 3, Suite 4 next door and multiple spaces upstairs near Big Car. www.bigcar.org
Friday, March 6, 2009.
Big Car's First Friday show for March featured a bevy of local, regional, national and international video and sound artists. All of the music accompanied video art projections. The night included a show of Herron video artists in Suite 214 next door to Big Car (see artist statements below), a program of experimental videos from other local artists in Suite 3 and 4 on street level (J. Andrew Salyer, Jennie Mynhier, Laura Salyer, Jim Walker, Flounder Lee) and a Microcinema screening (FATELESS, Color + Modulation, SLIDE, Hub Culture Retrospectives: Antarctica, Independent Exposure: Asthmatic Kitty Records Edition 2008, The Collected Films of Ryan Jeffery, Op Art, Modular Moves, Jellies: The Art of Nature) also in Suite 214. For more about Microcinema visit www.microcinema.com.
The night's musical offerings in Suite 215 (Big Car's regular space) and in other nearby spaces included performances by Butler University's Ensemble 48 (playing a soundtrack to the silent film "Man with the Movie Camera"), Marck Ferrari, Ben Ishmael Revival, Shiny Black Shirt, Sea Krowns, Ensemble 48, Actuel, Playboy Psychonauts, Stallio, Sky Thing and Tonos Triad.
Also in the street level space that night, Big Car also hosted the installation "Unified Fields" that featured the interactive music and art of duo Mana2 (Jordan Munson, Michael Drews).
The event was sponsored by Microcinema and was a partnership with the Toby at the IMA.
PCM bays to the left. The programme entered the site as PCM (Pulse-Code Modulation) via Carlisle link, and was decoded and fed into the transmitter drives.
From Don Edwards San Francisco Bay National Wildlife Reserve, near Drawbridge, the Weep Site, north connector, on Feb. 18, 2008. Salinity = 52-PPT. Photomicrograph taken at 1,000x magnification, oil immersion, with Hoffman Modulation optics. This Cyanobacterial filament exhibited a well-defined sheath and was not motile. This filament represents the majority of Cyanobacterial filaments found at this site at this date. By May, as the Weep Site evaporated and the salinity went up above 100-PPT, the Cyanobacteria vanished, to be replaced by a community of Dinoflagellates.
Dimensions: 20" wide X 10" tall X 12" deep.
Uses standard 1/4" jacks for audio out and patch panel.
Monophonic, with low-pass filter, envelope (HADSR) controls, LFO, pitch width modulation, white and pink noise generation, and external signal in jack.
About the Korg MS-10:
Xung PWM là cụm từ viết tắt của Pulse Width Modulation, giải nghĩa hiểu đơn giản thì xung PWM là một loại tín hiệu được ứng dụng trong vật lý để điều chỉnh điện áp tải ra của các thiết bị điện tử, thiết bị điện dựa trên sự thay đổi về độ rộng của chuỗi xung vuông, điều này dẫn đến sự thay đổi điện áp ra.
Các PWM khi biến đổi sẽ có cùng 1 tần số và khác nhau về độ rộng của sườn dương hay sườn âm.
👉Tham khảo thêm bài viết sau đây để rõ hơn.
shadow.vn/pwm-la-gi-va-anh-huong-den-den-pin-nhu-the-nao
SHADOW Việt Nam - Chuyên cung cấp đèn pin cao cấp, đèn pin nhập khẩu chính hãng
Add: Số 51A Phan Kế Bính, phường Cống Vị, quận Ba Đình, Hà Nội
SĐT: 0934883366
TIN: 0108618521
--------------------------------
Các trang mạng xã hội khác của Shadow Việt Nam:
dribbble.com/shots/19683553-Xung-PWM-l-g-r-ng-xung-nh-h-n...
linkhay.com/blog/390918/xung-pwm-la-gi-do-rong-xung-anh-h...
The rope & pulley prototype set up at ITP for a user testing session. When my right side faces the computer, pulling the rope towards my body triggers a note on the MIDI synthesizer. Pulling the rope with increasing speed increases the volume of the note as well as a sound modulating parameter. Decreasing the pulley's speed decreases the volume and modulation parameter. When the pulley stops rotating, the system turns off the note on the synthesizer.
This synth has lots of knobs for direct control over all the important parameters but also has a deep menu system with lots of possibilities.
A very underrated synth but I love it!
Demos:
(1) Modulation Sequencers:
www.youtube.com/watch?v=hQCDXRs3O7A
(2) Stunning vocoder based song
www.youtube.com/watch?v=QGdHsdL9op4
(3) Dance, not my style but a good demo.
JW4103 optic talk setwith Red Light Source 60KM
Description
JW4103 Optical Talk Set is an intelligent and efficient instrument that combines in one set the functions of both a digital optical phone and a stabilized light source. It is widely used in operations of installation, optical testing, maintenance and fiber attenuation value testing in data network, CATV and Telecommunication network. The JW4103 Talk Set can carry out full-duplex communication with high quality connection and not be affected by distance.
Features:
Full-duplex digital communication with high quality conversation connection and low background noise
Together with Optical Clip-on Coupler, enables on line communications available
Combining functions of both a digital optical phone call and a stabilized light source
Large LCD display with backlight
Low battery power indication
Applications:
Maintenance in Telecom
Maintenance CATV
Test Lab of optical fibers
Other Fiber Optic Measurements
Specification:
Type
JW4103
Wavelength(nm)
1310/1550
Emitter Type
FP-LD
Transmission Distance
≥ 80km
Dynamic Range
40dB
Output Power
-5~-7dBm(9/125um), CW or 2KHz, 1KHz, 270Hz Modulation
Output Stabvlity
± 0.1dB/± 0.25dB(1/8hrs) CW
Power Supply
Rechargeable Battery + Power Supply Adaptor
Battery Operating Time
5 hours
Optical Connector
FC/PC
Operating Temperatrue(C)
-10 ~ +60
Storage Temperatrue(C)
-25 ~ +70
Dimension(mm)
215X115X55
The layering corresponds to Milankovitch cycle
Graham P. Weedon:
"The 21 000 year (21 ka) precession cycle was detected in all three cases, the 100 ka eccentricity cycle in two cases and the 41 ka obliquity cycle in one. Filtering revealed that the supposed 21 ka sedimentary cycles are grouped into packets of four or five small and large amplitude cycles. The packets reflect the 100 ka modulation of the 21 ka precession cycle. Local disruption of the packaging can be used to locate hiatuses in pelagic strata."
source: jgs.lyellcollection.org/cgi/content/abstract/ 146/1/133
Headset (HS02) assembly showing placement of Tx coil interface about the left eye. The Class-AB coil driver is controlled via a 50MHz Direct Digital Synthesizer DDS that includes high speed Frequency and Phase modulation control of telemetry data. The headset Virtex6 FPGA controls the DDS class-AB coil driver.
12 Interlocking Irregular Hyperboloidal Dodecahedra 360 units
2-fold view.
Following an initial prototype with only a singular unit type which attempted a hexahedral symmetry analog of 30 Dodecahedra, I developed this more nuanced version, which has a different exterior weaving pattern and multiple paper proportions. However, as a constraint, I attempted to use only one pocket type for all of the units. This makes some vertices different than others in terms of the dihedral angles of the surrounding units, but the edges shafts are long enough to accommodate modulation between vertices without appreciable difficulty in most cases. This is constructed via scaffolding so that each dodecahedron represents one edge of a cube. The resulting compound is at the time of writing this, the largest interlocking origami cubic symmetry wireframe compound by unit count that I know of.
Designed by me.
Folded out of Cordenons’ Stardream paper.
With an array of hardware controls, MPK Mini lets you record, compose, and perform with virtual instruments, effect plugins, and DAWs whenever inspiration strikes. It features 25 velocity-sensitive synth-action keys, a 4-way thumbstick for dynamic pitch and modulation manipulation, 8 backlit velocity-sensitive MPC-style pads, and 8 assignable Q-Link knobs. Plus, two banks expand the number of MPC-style pads to 16 for extended creative capabilities.
More Info / Available here:
www.recordcase.de/en/AKAI+Professional+MPK+Mini.htm?pid=G...
Garland Fielder 'White Cube', 2010, Holly Johnson Gallery, Dallas
Garland Fielder exhibit 'Modulations'
The mallard or wild duck (Anas platyrhynchos) is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa. It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. This duck belongs to the subfamily Anatinae of the waterfowl family Anatidae. Males have green heads, while the females (hens or ducks) have mainly brown-speckled plumage. Both sexes have an area of white-bordered black or iridescent purple or blue feathers called a speculum on their wings; males especially tend to have blue speculum feathers. The mallard is 50–65 cm (20–26 in) long, of which the body makes up around two-thirds the length. The wingspan is 81–98 cm (32–39 in) and the bill is 4.4 to 6.1 cm (1.7 to 2.4 in) long. It is often slightly heavier than most other dabbling ducks, weighing 0.7–1.6 kg (1.5–3.5 lb). Mallards live in wetlands, eat water plants and small animals, and are social animals preferring to congregate in groups or flocks of varying sizes.
The female lays 8 to 13 creamy white to greenish-buff spotless eggs, on alternate days. Incubation takes 27 to 28 days and fledging takes 50 to 60 days. The ducklings are precocial and fully capable of swimming as soon as they hatch.
The mallard is considered to be a species of least concern by the International Union for Conservation of Nature (IUCN). Unlike many waterfowl, mallards are considered an invasive species in some regions. It is a very adaptable species, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The non-migratory mallard interbreeds with indigenous wild ducks of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in the extinction of many indigenous waterfowl. This species is the main ancestor of most breeds of domestic duck, and its naturally evolved wild gene pool has been genetically polluted by the domestic and feral mallard populations.
Taxonomy and evolutionary history
The mallard was one of the many bird species originally described in the 1758 10th edition of Systema Naturae by Carl Linnaeus. He gave it two binomial names: Anas platyrhynchos and Anas boschas.The latter was generally preferred until 1906 when Einar Lönnberg established that A. platyrhynchos had priority, as it appeared on an earlier page in the text. The scientific name comes from Latin Anas, "duck" and Ancient Greek πλατυρυγχος, platyrhynchus, "broad-billed" (from πλατύς, platys, "broad" and ρυγχός, rhunkhos, "bill"). The genome of Anas platyrhynchos was sequenced in 2013.
The name mallard originally referred to any wild drake, and it is sometimes still used this way. It was derived from the Old French malart or mallart for "wild drake" although its true derivation is unclear. It may be related to, or at least influenced by, an Old High German masculine proper name Madelhart, clues lying in the alternative English forms "maudelard" and "mawdelard". Masle (male) has also been proposed as an influence.
Mallards frequently interbreed with their closest relatives in the genus Anas, such as the American black duck, and also with species more distantly related, such as the northern pintail, leading to various hybrids that may be fully fertile. The mallard has hybridized with more than 40 species in the wild, and an additional 20 species in captivity, though fertile hybrids typically have two Anas parents. Mallards and their domestic conspecifics are fully interfertile; many wild mallard populations in North America contain significant amounts of domestic mallard DNA.
Genetic analysis has shown that certain mallards appear to be closer to their Indo-Pacific relatives, while others are related to their American relatives. Mitochondrial DNA data for the D-loop sequence suggest that mallards may have evolved in the general area of Siberia. Mallard bones rather abruptly appear in food remains of ancient humans and other deposits of fossil bones in Europe, without a good candidate for a local predecessor species. The large Ice Age palaeosubspecies that made up at least the European and West Asian populations during the Pleistocene has been named Anas platyrhynchos palaeoboschas.
Mallards are differentiated in their mitochondrial DNA between North American and Eurasian populations,[19] but the nuclear genome displays a notable lack of genetic structure. Haplotypes typical of American mallard relatives and eastern spot-billed ducks can be found in mallards around the Bering Sea. The Aleutian Islands hold a population of mallards that appear to be evolving towards becoming a subspecies, as gene flow with other populations is very limited.
Also, the paucity of morphological differences between the Old World mallards and the New World mallard demonstrates the extent to which the genome is shared among them such that birds like the Chinese spot-billed duck are highly similar to the Old World mallard, and birds such as the Hawaiian duck are highly similar to the New World mallard.
The size of the mallard varies clinally; for example, birds from Greenland, though larger, have smaller bills, paler plumage, and stockier bodies than birds further south and are sometimes classified as a separate subspecies, the Greenland mallard (A. p. conboschas).
Description
The mallard is a medium-sized waterfowl species that is often slightly heavier than most other dabbling ducks. It is 50–65 cm (20–26 in) long – of which the body makes up around two-thirds – has a wingspan of 81–98 cm (32–39 in),[24]: 505 and weighs 0.7–1.6 kg (1.5–3.5 lb).[25] Among standard measurements, the wing chord is 25.7 to 30.6 cm (10.1 to 12.0 in), the bill is 4.4 to 6.1 cm (1.7 to 2.4 in), and the tarsus is 4.1 to 4.8 cm (1.6 to 1.9 in). The breeding male mallard is unmistakable, with a glossy bottle-green head and a white collar that demarcates the head from the purple-tinged brown breast, grey-brown wings, and a pale grey belly. The rear of the male is black, with white-bordered dark tail feathers. The bill of the male is a yellowish-orange tipped with black, with that of the female generally darker and ranging from black to mottled orange and brown. The female mallard is predominantly mottled, with each individual feather showing sharp contrast from buff to very dark brown, a coloration shared by most female dabbling ducks, and has buff cheeks, eyebrow, throat, and neck, with a darker crown and eye-stripe. Mallards, like other sexually-dimorphic birds, can sometimes go though spontaneous sex reversal, often caused by damaged or nonfunctioning sex organs, such as the ovaries in mallard hens. This phenomenon can cause female mallards to exhibit male plumage, and vice versa (phenotypic feminisation or masculinisation).
Both male and female mallards have distinct iridescent purple-blue speculum feathers edged with white, which are prominent in flight or at rest but temporarily shed during the annual summer moult. Upon hatching, the plumage of the duckling is yellow on the underside and face (with streaks by the eyes) and black on the back (with some yellow spots) all the way to the top and back of the head. Its legs and bill are also black. As it nears a month in age, the duckling's plumage starts becoming drab, looking more like the female, though more streaked, and its legs lose their dark grey colouring. Two months after hatching, the fledgling period has ended, and the duckling is now a juvenile. The duckling is able to fly 50–60 days after hatching. Its bill soon loses its dark grey colouring, and its sex can finally be distinguished visually by three factors: 1) the bill is yellow in males, but black and orange in females; 2) the breast feathers are reddish-brown in males, but brown in females; and 3) in males, the centre tail feather (drake feather) is curled, but in females, the centre tail feather is straight. During the final period of maturity leading up to adulthood (6–10 months of age), the plumage of female juveniles remains the same while the plumage of male juveniles gradually changes to its characteristic colours. This change in plumage also applies to adult mallard males when they transition in and out of their non-breeding eclipse plumage at the beginning and the end of the summer moulting period. The adulthood age for mallards is fourteen months, and the average life expectancy is three years, but they can live to twenty.
Several species of duck have brown-plumaged females that can be confused with the female mallard. The female gadwall (Mareca strepera) has an orange-lined bill, white belly, black and white speculum that is seen as a white square on the wings in flight, and is a smaller bird. More similar to the female mallard in North America are the American black duck (A. rubripes), which is notably darker-hued in both sexes than the mallard, and the mottled duck (A. fulvigula), which is somewhat darker than the female mallard, and with slightly different bare-part colouration and no white edge on the speculum.
Mallards are among the most common bird species to exhibit aberrant colouration, typically due to genetic mutations.[39] The female pictured here is leucistic; leucism in birds often results in 'cream-colored', 'apricot' or muted feathers on certain parts of the body.
In captivity, domestic ducks come in wild-type plumages, white, and other colours. Most of these colour variants are also known in domestic mallards not bred as livestock, but kept as pets, aviary birds, etc., where they are rare but increasing in availability.
A noisy species, the female has the deep quack stereotypically associated with ducks. Male mallards make a sound phonetically similar to that of the female, a typical quack, but it is deeper and quieter compared to that of the female. Research conducted by Middlesex University on two English mallard populations found that the vocalisations of the mallard varies depending on their environment and have something akin to a regional accent, with urban mallards in London being much louder and more vociferous compared to rural mallards in Cornwall, serving as an adaptation to persistent levels of anthropogenic noise.
When incubating a nest, or when offspring are present, females vocalise differently, making a call that sounds like a truncated version of the usual quack. This maternal vocalisation is highly attractive to their young. The repetition and frequency modulation of these quacks form the auditory basis for species identification in offspring, a process known as acoustic conspecific identification. In addition, females hiss if the nest or offspring are threatened or interfered with. When taking off, the wings of a mallard produce a characteristic faint whistling noise.
The mallard is a rare example of both Allen's Rule and Bergmann's Rule in birds. Bergmann's Rule, which states that polar forms tend to be larger than related ones from warmer climates, has numerous examples in birds, as in case of the Greenland mallard which is larger than the mallards further south. Allen's Rule says that appendages like ears tend to be smaller in polar forms to minimise heat loss, and larger in tropical and desert equivalents to facilitate heat diffusion, and that the polar taxa are stockier overall. Examples of this rule in birds are rare as they lack external ears, but the bill of ducks is supplied with a few blood vessels to prevent heat loss, and, as in the Greenland mallard, the bill is smaller than that of birds farther south, illustrating the rule.
Due to the variability of the mallard's genetic code, which gives it its vast interbreeding capability, mutations in the genes that decide plumage colour are very common and have resulted in a wide variety of hybrids, such as Brewer's duck (mallard × gadwall, Mareca strepera).
Distribution and habitat
The mallard is widely distributed across the Northern and Southern Hemispheres; in North America its range extends from southern and central Alaska to Mexico, the Hawaiian Islands, across the Palearctic, from Iceland and southern Greenland and parts of Morocco (North Africa) in the west, Scandinavia and Britain to the north, and to Siberia, Japan, and South Korea. Also in the east, it ranges to south-eastern and south-western Australia and New Zealand in the Southern hemisphere. It is strongly migratory in the northern parts of its breeding range, and winters farther south. For example, in North America, it winters south to the southern United States and northern Mexico, but also regularly strays into Central America and the Caribbean between September and May. A drake later named "Trevor" attracted media attention in 2018 when it turned up on the island of Niue, an atypical location for mallards.
The mallard inhabits a wide range of habitats and climates, from the Arctic tundra to subtropical regions. It is found in both fresh- and salt-water wetlands, including parks, small ponds, rivers, lakes and estuaries, as well as shallow inlets and open sea within sight of the coastline. Water depths of less than 0.9 metres (3.0 ft) are preferred, with birds avoiding areas more than a few metres deep. They are attracted to bodies of water with aquatic vegetation.
Behaviour
The mallard is omnivorous and very flexible in its choice of food. Its diet may vary based on several factors, including the stage of the breeding cycle, short-term variations in available food, nutrient availability, and interspecific and intraspecific competition. The majority of the mallard's diet seems to be made up of gastropods, insects (including beetles, flies, lepidopterans, dragonflies, and caddisflies), crustaceans, other arthropods, worms, many varieties of seeds and plant matter, and roots and tubers. During the breeding season, male birds were recorded to have eaten 37.6% animal matter and 62.4% plant matter, most notably the grass Echinochloa crus-galli, and nonlaying females ate 37.0% animal matter and 63.0% plant matter, while laying females ate 71.9% animal matter and only 28.1% plant matter. Plants generally make up the larger part of a bird's diet, especially during autumn migration and in the winter.
The mallard usually feeds by dabbling for plant food or grazing; there are reports of it eating frogs. However, in 2017 a flock of mallards in Romania were observed hunting small migratory birds, including grey wagtails and black redstarts, the first documented occasion they had been seen attacking and consuming large vertebrates. It usually nests on a river bank, but not always near water. It is highly gregarious outside of the breeding season and forms large flocks, which are known as "sordes".
Breeding
Mallards usually form pairs (in October and November in the Northern Hemisphere) until the female lays eggs at the start of the nesting season, which is around the beginning of spring. At this time she is left by the male who joins up with other males to await the moulting period, which begins in June (in the Northern Hemisphere). During the brief time before this, however, the males are still sexually potent and some of them either remain on standby to sire replacement clutches (for female mallards that have lost or abandoned their previous clutch) or forcibly mate with females that appear to be isolated or unattached regardless of their species and whether or not they have a brood of ducklings.
Nesting sites are typically on the ground, hidden in vegetation where the female's speckled plumage serves as effective camouflage, but female mallards have also been known to nest in hollows in trees, boathouses, roof gardens and on balconies, sometimes resulting in hatched offspring having difficulty following their parent to water.
Egg clutches number 8–13 creamy white to greenish-buff eggs free of speckles. They measure about 58 mm (2.3 in) in length and 32 mm (1.3 in) in width.[90] The eggs are laid on alternate days, and incubation begins when the clutch is almost complete. Incubation takes 27–28 days and fledging takes 50–60 days. The ducklings are precocial and fully capable of swimming as soon as they hatch. However, filial imprinting compels them to instinctively stay near the mother, not only for warmth and protection but also to learn about and remember their habitat as well as how and where to forage for food. Though adoptions are known to occur, female mallards typically do not tolerate stray ducklings near their broods, and will violently attack and drive away any unfamiliar young, sometimes going as far as to kill them.
When ducklings mature into flight-capable juveniles, they learn about and remember their traditional migratory routes (unless they are born and raised in captivity). In New Zealand, where mallards are naturalised, the nesting season has been found to be longer, eggs and clutches are larger and nest survival is generally greater compared with mallards in their native range.
In cases where a nest or brood fails, some mallards may mate for a second time in an attempt to raise a second clutch, typically around early-to-mid summer. In addition, mallards may occasionally breed during the autumn in cases of unseasonably warm weather; one such instance of a 'late' clutch occurred in November 2011, in which a female successfully hatched and raised a clutch of eleven ducklings at the London Wetland Centre.
During the breeding season, both male and female mallards can become aggressive, driving off competitors to themselves or their mate by charging at them. Males tend to fight more than females and attack each other by repeatedly pecking at their rival's chest, ripping out feathers and even skin on rare occasions. Female mallards are also known to carry out 'inciting displays', which encourage other ducks in the flock to begin fighting. It is possible that this behaviour allows the female to evaluate the strength of potential partners.
The drakes that end up being left out after the others have paired off with mating partners sometimes target an isolated female duck, even one of a different species, and proceed to chase and peck at her until she weakens, at which point the males take turns copulating with the female. Lebret (1961) calls this behaviour "Attempted Rape Flight", and Stanley Cramp and K.E.L. Simmons (1977) speak of "rape-intent flights". Male mallards also occasionally chase other male ducks of a different species, and even each other, in the same way. In one documented case of "homosexual necrophilia", a male mallard copulated with another male he was chasing after the chased male died upon flying into a glass window. This paper was awarded an Ig Nobel Prize in 2003.
Mallards are opportunistically targeted by brood parasites, occasionally having eggs laid in their nests by redheads, ruddy ducks, lesser scaup, gadwalls, northern shovelers, northern pintails, cinnamon teal, common goldeneyes, and other mallards. These eggs are generally accepted when they resemble the eggs of the host mallard, but the hen may attempt to eject them or even abandon the nest if parasitism occurs during egg laying.
Predators and threats
In addition to human hunting, mallards of all ages (but especially young ones) and in all locations must contend with a wide diversity of predators including raptors and owls, mustelids, corvids, snakes, raccoons, opossums, skunks, turtles, large fish, felids, and canids, the last two including domestic cats and dogs. The most prolific natural predators of adult mallards are red foxes (Vulpes vulpes; which most often pick off brooding females) and the faster or larger birds of prey, (e.g. peregrine falcons, Aquila or Haliaeetus eagles). In North America, adult mallards face no fewer than 15 species of birds of prey, from northern harriers (Circus hudsonius) and short-eared owls (Asio flammeus) (both smaller than a mallard) to huge bald (Haliaeetus leucocephalus) and golden eagles (Aquila chrysaetos), and about a dozen species of mammalian predators, not counting several more avian and mammalian predators who threaten eggs and nestlings.
Mallards are also preyed upon by other waterside apex predators, such as grey herons (Ardea cinerea), great blue herons (Ardea herodias) and black-crowned night herons (Nycticorax nycticorax), the European herring gull (Larus argentatus), the wels catfish (Silurus glanis), and the northern pike (Esox lucius). Crows (Corvus spp.) are also known to kill ducklings and adults on occasion. Also, mallards may be attacked by larger anseriformes such as swans (Cygnus spp.) and geese during the breeding season, and are frequently driven off by these birds over territorial disputes. Mute swans (Cygnus olor) have been known to attack or even kill mallards if they feel that the ducks pose a threat to their offspring. Common loons (Gavia inmer) are similarly territorial and aggressive towards other birds in such disputes, and will frequently drive mallards away from their territory. However, in 2019, a pair of common loons in Wisconsin were observed raising a mallard duckling for several weeks, having seemingly adopted the bird after it had been abandoned by its parents.
The predation-avoidance behaviour of sleeping with one eye open, allowing one brain hemisphere to remain aware while the other half sleeps, was first demonstrated in mallards, although it is believed to be widespread among birds in general.
Status and conservation
Since 1998, the mallard has been rated as a species of least concern on the IUCN Red List of Endangered Species. This is because it has a large range–more than 20,000,000 km2 (7,700,000 mi2) and because its population is increasing, rather than declining by 30% over ten years or three generations and thus is not warranted a vulnerable rating. Also, the population size of the mallard is very large.
Unlike many waterfowl, mallards have benefited from human alterations to the world – so much so that they are now considered an invasive species in some regions. They are a common sight in urban parks, lakes, ponds, and other human-made water features in the regions they inhabit, and are often tolerated or encouraged in human habitat due to their placid nature towards humans and their beautiful and iridescent colours. While most are not domesticated, mallards are so successful at coexisting in human regions that the main conservation risk they pose comes from the loss of genetic diversity among a region's traditional ducks once humans and mallards colonise an area. Mallards are very adaptable, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The release of feral mallards in areas where they are not native sometimes creates problems through interbreeding with indigenous waterfowl. These non-migratory mallards interbreed with indigenous wild ducks from local populations of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in the extinction of many indigenous waterfowl. The mallard itself is the ancestor of most domestic ducks, and its naturally evolved wild gene pool gets genetically polluted in turn by the domestic and feral populations. Over time, a continuum of hybrids ranging between almost typical examples of either species develop; the speciation process is beginning to reverse itself. This has created conservation concerns for relatives of the mallard, such as the Hawaiian duck, the New Zealand grey duck (A. s. superciliosa) subspecies of the Pacific black duck, the American black duck, the mottled duck, Meller's duck, the yellow-billed duck, and the Mexican duck, in the latter case even leading to a dispute as to whether these birds should be considered a species (and thus entitled to more conservation research and funding) or included in the mallard species. Ecological changes and hunting have also led to a decline of local species; for example, the New Zealand grey duck population declined drastically due to overhunting in the mid-20th century. Hybrid offspring of Hawaiian ducks seem to be less well adapted to native habitat, and using them in re-introduction projects apparently reduces success. In summary, the problems of mallards "hybridising away" relatives is more a consequence of local ducks declining than of mallards spreading; allopatric speciation and isolating behaviour have produced today's diversity of mallard-like ducks despite the fact that, in most, if not all, of these populations, hybridisation must have occurred to some extent.
Invasiveness
Mallards are causing severe "genetic pollution" to South Africa's biodiversity by breeding with endemic ducks even though the Agreement on the Conservation of African-Eurasian Migratory Waterbirds – an agreement to protect the local waterfowl populations – applies to the mallard as well as other ducks.[131] The hybrids of mallards and the yellow-billed duck are fertile, capable of producing hybrid offspring. If this continues, only hybrids occur and in the long term result in the extinction of various indigenous waterfowl. The mallard can crossbreed with 63 other species, posing a severe threat to indigenous waterfowl's genetic integrity. Mallards and their hybrids compete with indigenous birds for resources, including nest sites, roosting sites, and food.
Availability of mallards, mallard ducklings, and fertilised mallard eggs for public sale and private ownership, either as poultry or as pets, is currently legal in the United States, except for the state of Florida, which has currently banned domestic ownership of mallards. This is to prevent hybridisation with the native mottled duck.
The mallard is considered an invasive species in Australia and New Zealand, where it competes with the Pacific black duck (known as the grey duck locally in New Zealand) which was over-hunted in the past. There, and elsewhere, mallards are spreading with increasing urbanisation and hybridising with local relatives.
The eastern or Chinese spot-billed duck is currently introgressing into the mallard populations of the Primorsky Krai, possibly due to habitat changes from global warming. The Mariana mallard was a resident allopatric population – in most respects a good species – apparently initially derived from mallard-Pacific black duck hybrids; it became extinct in the late 20th century.
The Laysan duck is an insular relative of the mallard, with a very small and fluctuating population. Mallards sometimes arrive on its island home during migration, and can be expected to occasionally have remained and hybridised with Laysan ducks as long as these species have existed. However, these hybrids are less well adapted to the peculiar ecological conditions of Laysan Island than the local ducks, and thus have lower fitness. Laysan ducks were found throughout the Hawaiian archipelago before 400 AD, after which they suffered a rapid decline during the Polynesian colonisation.Now, their range includes only Laysan Island. It is one of the successfully translocated birds, after having become nearly extinct in the early 20th century.
Relationship with humans
Mallards have often been ubiquitous in their regions among the ponds, rivers, and streams of human parks, farms, and other human-made waterways – even to the point of visiting water features in human courtyards.
George Hetzel, mallard still life painting, 1883–1884
Mallards have had a long relationship with humans. Almost all domestic duck breeds derive from the mallard, with the exception of a few Muscovy breeds, and are listed under the trinomial name A. p. domesticus. Mallards are generally monogamous while domestic ducks are mostly polygamous. Domestic ducks have no territorial behaviour and are less aggressive than mallards. Domestic ducks are mostly kept for meat; their eggs are also eaten, and have a strong flavour. They were first domesticated in Southeast Asia at least 4,000 years ago, during the Neolithic Age, and were also farmed by the Romans in Europe, and the Malays in Asia. As the domestic duck and the mallard are the same species as each other, it is common for mallards to mate with domestic ducks and produce hybrid offspring that are fully fertile. Because of this, mallards have been found to be contaminated with the genes of the domestic duck.
While the keeping of domestic breeds is more popular, pure-bred mallards are sometimes kept for eggs and meat, although they may require wing clipping to restrict flying.
Hunting
Mallards are one of the most common varieties of ducks hunted as a sport due to the large population size. The ideal location for hunting mallards is considered to be where the water level is somewhat shallow where the birds can be found foraging for food. Hunting mallards might cause the population to decline in some places, at some times, and with some populations. In certain countries, the mallard may be legally shot but is protected under national acts and policies. For example, in the United Kingdom, the mallard is protected under the Wildlife and Countryside Act 1981, which restricts certain hunting methods or taking or killing mallards.
As food
Since ancient times, the mallard has been eaten as food. The wild mallard was eaten in Neolithic Greece. Usually, only the breast and thigh meat is eaten. It does not need to be hung before preparation, and is often braised or roasted, sometimes flavoured with bitter orange or with port.
Garland Fielder 'White Cube', 2010, Holly Johnson Gallery, Dallas
Garland Fielder exhibit 'Modulations'
Home, still feeling sick. I decided to finally go and look at the circuit.
The two diode 555 pwm, MOSFET low-side power switch, excess
instrumentation and rat's nest wiring. :)
The Dirty Carter Electronic Sound Generating Instrument was designed by John Richards (Dirty Electronics) and Chris Carter from legendary Industrial pioneers Throbbing Gristle. It was produced for a special performance by Carter and the 25 strong Dirty Electronics Ensemble in 2010. It was originally designed as a touch controlled instrument with the player's skin resistance completing the circuit. This hard wired modification by A.S.M.O. gives more control and predictability by wiring all to the touch contacts to pots and switches. An additional low pass resonant filter has been added, LFO and an external CV socket for filter modulation.
The case is made of stained ply and the front panel is covered with black leatherette.
Plaster cast, 1813
(date carved in plaster with Author’s inscription)
Current placing: Scarpa wing, cm 175x103x64
This is the marble model which can be found at the Hermitage in S.Petersbourg (Russia). Another plaster cast representing the Grazie can be found in the Council Chamber at Possagno. There are some variations on the model: instead of a stele, a tree trunk acts as a stand): This is a marble cast which can be found at the Museum in Edinburgh (Scotland- UK). The poetical expression of the Grazie represents sweetness, affection as well as agility and harmony: the three goddesses have just come out from the fountain where they had been bathing (Carlo Scarpa actually wanted to place them near a fountain), they embrace each other creating a pleasant interlacement. They bow their heads tenderly creating a harmonious modulation of bodies. The firmness of their flesh as well as the delicacy of their nimble bodies make this work one of the best-known masterpieces by Canova.
Title: Concha Renaissance San Juan Resort
Other title: Concha
Creator: Toro, Osvaldo 1914-1995; Ferrer, Miguel, 1915-2004; Salvadori, Mario George, 1907-1997; Marvel & Marchand Architects
Creator role: Architect
Date: 1958 (original) 2008 (renovation)
Current location: San Juan, Puerto Rico
Description of work: Renaissance Hotels tasked architect Jose R. Marchand and interior designer Jorge Rossello with renovating and saving this beachside landmark. "[B]y the mid-1990s the venerable La Concha hotel had been shuttered, abandoned and left to rot...Originally designed by Osvaldo Toro and Miguel Ferrer, with an eccentric but utterly loveable seashell-shaped restaurant by Mario Salvatori [sic], La Concha was a beautifully massed, expertly sited, vividly inventive building perfectly in sync with its time. Closely attuning the hotel to its sun-swept setting, the architects created deep-shading overhangs, open corridors, windows and doors that gave onto lush interior courtyards and provided cross ventilation, and beautifully lacy quiebra-sol (their take on a brise-soleil) for further modulation of the light and heat" (Frank, Michael. "La Concha Revival". Architectural Digest. Aug 2009, p. 103-104. Print).
Description of view: View of the outdoor shower and spa area by the beachfront pool.
Work type: Architecture and Landscape
Style of work: Modern: International Style
Culture: Puerto Rican
Materials/Techniques: Concrete
Plants
Trees
Source: Pisciotta, Henry (copyright Henry Pisciotta)
Date photographed: May 13, 2008
Resource type: Image
File format: JPEG
Image size: 2304H X 3072W pixels
Permitted uses: This image is posted publicly for non-profit educational uses, excluding printed publication. Other uses are not permitted. For additional details see: alias.libraries.psu.edu/vius/copyright/publicrightsarch.htm
Collection: Worldwide Building and Landscape Pictures
Filename: WB2010-0280 Concha.JPG
Record ID: WB2010-0280
Sub collection: resorts
Copyright holder: Copyright Henry Pisciotta