wiktionary The term nearfield can refer to near field mathematics , an algebraic structure near and far field , parts of an electromagnetic field disambig ... more details
File ADAM A5 active monitor IBC 2008.jpg thumb ADAM A5 near field active monitor ADAM Audio is a loudspeaker manufacturing company, based in Berlin , Germany . The company offers home loudspeakers these are quite unusual being typically active speaker active and studio monitor s. The latter range from nearfield to big main monitors. Both ranges may be supplemented with ADAM subwoofer s. Newest product is a preamplifier. ADAM loudspeakers are often praised for their open and clear presentation of high frequencies. ref name sosreview http www.soundonsound.com sos nov06 articles adam.htm Review of Adam A7 monitor in Sound on Sound magazine ref This is achieved by using an Tweeter AMT tweeter Air Motion Transformer variety of tweeter design, a folded ribbon called A.R.T. Accelerating Ribbon Technology ref name ARTdescription http www.adam audio.com art page1.htm Description of Accelerating Ribbon Technology on ADAM website ref . A.R.T. is also used on midranges in bigger speaker models. References references External links http www.adam audio.com ADAM Audio home page DEFAULTSORT Adam Audio Category Companies based in Berlin Category Loudspeaker manufacturers Germany company stub sv ADAM Audio ... more details
cleanup article date March 2008 Acoustic holography is a method that is used to estimate the sound field near a source by measuring Acoustics acoustic parameters away from the source via an array of pressure and or particle velocity transducers . Measuring techniques included within acoustic holography are becoming increasingly popular in various fields, most notably those of transportation, vehicle and aircraft design, and Noise, vibration, and harshness NVH Noise, vibration, and harshness . The general idea of acoustic holography has led to different versions such as near field acoustic holography NAH and statistically optimal near field acoustic holography SONAH . For audio rendition, the wave field synthesis is the most related procedure. References Reflist cite journal author J. D. Maynard, E. G. Williams, and Y. Lee title Nearfield acoustic holography I. Theory of generalized holography and the development of NAH journal The Journal of the Acoustical Society of America month October year 1985 volume 78 issue 4 pages 1395&ndash 1413 doi 10.1121 1.392911 bibcode 1985ASAJ...78.1395M cite conference author J. Hald title Patch near field acoustical holography using a new statistically optimal method booktitle Inter noise 2003, Jeju International Convention Center, Seogwipo, Korea, 2003 08 25&ndash 2003 08 28 External links http www.acoustic holography.com Acoustic holography http www.lmsintl.com acoustic holography An introduction to Acoustic Holography DEFAULTSORT Acoustic Holography Category Acoustics Category Sound measurements physics stub ... more details
File Swas 1.jpg thumb 250px Submillimeter Wave Astronomy Satellite SWAS The Submillimeter Wave Astronomy Satellite SWAS was an astronomical observatory launched on December 5, 1998 as part of the Small Explorer program within NASA . Investigators at Smithsonian Astrophysical Observatory and Goddard Space Flight Center designed the telescope and the spacecraft, respectively. The satellite examined microwaves from 487 556 GHz that originated in water molecules, molecular oxygen, atomic carbon, and carbon monoxide in space. This corresponds to wavelengths of about 0.54 to 0.61 millimeters 540 to 610 m . ref http www.nearfield.com amta amta94ds.htm Nearfield SWAS reF SWAS made observations until July 21, 2004. In June 2005, the spacecraft was reactivated for a 3 month period after a year of stand by operation in order to observe the effects of the Deep Impact spacecraft Deep Impact probe s collision with comet 9P Tempel P Tempel 1 . ref cite web url http lambda.gsfc.nasa.gov product swas title The SWAS Mission publisher NASA year 2008 accessdate 2008 12 12 ref The main optic of SWAS is a 55 cm x 71 cm elliptical off axis Cassegrain telescope, sending light into a pair of Schottky diode receivers. reF http irsa.ipac.caltech.edu Missions swas.html IRSA SWAS Caltech ref SWAS observed a unique area of the spectrum alternately described as submillimeter for the wavelength of light seen , microwave, radio, and or far infrared. class wikitable style text align center font size 11px float left margin 2px bgcolor style font size smaller colspan 8 align center Comparison ref http herschel.jpl.nasa.gov relatedMissions.shtml JPL Herschel Space Observatory Related Missions ref Name Year Wavelength Aperture Human Eye 0.39 0.75 m 0.01 m SWAS 1998 540 610 m 0.55 0.7 Spitzer Space Telescope Spitzer 2003 3 180 m 0.85 m Hubble Space Telescope Hubble Wide Field Camera 3 WFC3 2009 0.2 1.7 m 2.4 m Herschel Space Observatory Herschel 2009 60 672 m 3.5 m clear See also Far infrared ... more details
for the large airplane built by Hughes Spruce goose In mathematics, a Hughes plane is one of the non Desarguesian projective plane s found by harvtxt Daniel Hughes 1957 . There are examples of order p sup 2 n sup for every odd prime p and every positive integer n . Construction The construction of a Hughes plane is based on a Near field mathematics nearfield N of order p sup 2n sup for p an odd prime whose kernel K has order p sup n sup and coincides with the center of N . Properties A Hughes plane H ref harvnb Dembowski 1968 loc pg.247 ref is a non Desarguesian projective plane of odd square prime power order of Lenz Barlotti type I.1, has a Desarguesian Baer subplane H sub 0 sub , is a self dual plane in which every orthogonal polarity of H sub 0 sub can be extended to a polarity of H , every central collineation of H sub 0 sub extends to a central collineation of H , and the full collineation group of H has two point orbits one of which is H sub 0 sub , two line orbits, and four flag orbits. The smallest Hughes Plane order 9 The Hughes plane of order 9 was actually found earlier by Veblen and Wedderburn in 1907. ref Citation last1 Veblen first1 O. last2 Wedderburn first2 J.H.M. title Non Desarguesian and non Pascalian geometries journal Transactions of the AMS year 1907 volume 8 pages 379 388 ref Notes reflist References Citation last Dembowski first P. title Finite Geometries year 1968 publisher Springer Verlag place Berlin Citation doi 10.4153 CJM 1957 045 0 last1 Hughes first1 D. R. title A class of non Desarguesian projective planes id MathSciNet id 0087960 year 1957 journal Canadian Journal of Mathematics. Journal Canadien de Math matiques issn 0008 414X volume 9 pages 378 388 url http www.cms.math.ca cjm v9 p378 Citation last1 Weibel first1 Charles title Survey of Non Desarguesian Planes url http www.ams.org notices 200710 year 2007 journal Notices of the AMS volume 54 issue 10 pages 1294 1303 Category Projective geometry Category Finite geometry ... more details
Edward M. Long is an audio engineer known for introducing the first near field studio monitor s ref cite web url http www.bobhodas.com educational resources.html title Speaker Placement and Acoustic Environment Effects on Nearfield Monitor Systems last Hodas first Bob month November year 1994 work Mix publisher Penton Media accessdate May 3, 2011 ref ref cite journal url http mixguides.com studiomonitors products features audio livin large title Livin Large last Petersen first George date November 1, 2007 work Mix publisher Penton Media accessdate May 3, 2011 ref and the first time aligned loudspeaker Audio crossover crossover . ref name Borwick cite book url http books.google.com books?id 9DeZqnsjetgC&pg PA474 pages 474 476 title Loudspeaker and headphone handbook last Borwick first John publisher Focal Press year 2001 isbn 0240515781 edition 3 ref ref cite journal url http mixonline.com TECnology Hall of Fame UREI 813 monitors 090106 title 1977 UREI 813 Studio Monitors date September 1, 2006 work Mix publisher Penton Media accessdate May 3, 2011 ref ref cite web url http tecfoundation.com hof 06techof.html title TECnology Hall of Fame 2006 work TECnology Hall of Fame publisher TEC Foundation accessdate May 3, 2011 ref Long worked with Bag End and Ron Wickersham, and developed a method for extending low frequency response in subwoofer s. ref cite web url http www.bagend.com elfm2eqreview.htm title ELF M2 Review work EQ magazine accessdate May 3, 2011 ref Long developed a passive crossover for loudspeakers which aligned the bandpasses in time. Patented in 1976 as Time Alignment , the crossover design was influential in loudspeaker development from the late 1970s throughout the 1980s. ref cite web url http www.aes.org e lib browse.cfm?elib 2283 title A Time Align Technique for Loudspeaker System Design last Long first Edward M. month May year 1976 work AES E Library publisher Audio Engineering Society location Oakland, California accessdate May 2, 2011 ref References ... more details
lateral extent of the target. At this point the synthetic aperture is within the target nearfield region ... can be measured by the analytic signal phase measurement method described earlier. Vertical nearfield ... more details
There be Peace 2003, ICC, ICCD77130 Still You Speak 2004, ICC Without the Song and Dance 2005, Nearfield CARGO Musical 2007, Nearfield Design with Paul Field Invisible Fire 1988, Krea Holland Garth Hewitt ... more details
File Nearfield optics.png thumb Diagram illustrating near field optics , with the diffraction of light coming from NSOM fiber probe, showing wavelength of light and the near field. Near field scanning optical microscopy NSOM SNOM is a microscopy technique for nanostructure investigation that breaks the far field Diffraction limited system resolution limit by exploiting the properties of evanescent waves . This is done by placing the detector very close distance much smaller than wavelength to the specimen surface. This allows for the surface inspection with high spatial, spectral and temporal Spectral resolution resolving power . With this technique, the resolution of the image is limited by the size of the detector aperture and not by the wavelength of the illuminating light. In particular, lateral resolution of 20 nm and vertical resolution of 2 5 nm have been demonstrated. ref cite journal author U. D rig et al. title Near field optical scanning microscopy journal J. Appl. Phys. volume 59 year 1986 page 3318 ref ref cite journal author Y. Oshikane et al. title Observation of nanostructure by scanning near field optical microscope with small sphere probe journal Sci. Technol. Adv. Mater. volume 8 year 2007 page 181 url http www.iop.org EJ article 1468 6996 8 3 A12 STAM 8 3 A12.pdf format free pdf doi 10.1016 j.stam.2007.02.013 issue 3 ref As in optical microscopy, the contrast mechanism can be easily adapted to study different properties, such as refractive index , chemical structure and local stress. Dynamic properties can also be studied at a sub wavelength scale using this technique. NSOM SNOM is a form of scanning probe microscopy . History Edward Hutchinson Synge, a scientist, is given credit for conceiving and developing the idea for an imaging instrument ... mechanism. ref name Olympus07 http www.olympusmicro.com primer techniques nearfield nearfieldintro.html ... Force Microscopy, Scanning Nearfield Optical Microscopy and Nanoscratching Application to Rough and Natural ... more details
measurement and its caveats. Nearfield measurements Room acoustics have much lower effect on nearfield ... Frequency Loudspeaker Assessment by Nearfield Sound Pressure Measurement, 1974 04 AES Published ref ... more details
with distance in the near and far field nearfield , typically 3 4 dB per doubling of distance ... nearfield. Devices like this generally have nearfields of only a few meters. However, sound radiated ... more details
SP 5B nearfield studio monitors ref http www.soundonsound.com sos feb02 articles maudiosp5b.asp ... USB Sound On Sound, Sep 2003 ref 2003 BX5 active nearfield reference studio monitors ref http ... more details
Distinguish Ambisonics Ambiophonics is a method in the public domain that employs digital signal processing DSP and two loudspeakers directly in front of the listener in order to improve reproduction of stereophonic and 5.1 surround sound for music, movies, and games in home theaters, gaming PCs, workstations, or studio monitoring applications. First implemented using mechanical means in 1986, ref Bock, T.M.and Keele, D.B. Jr., The Effects of Interaural Crosstalk on Stereo Reproduction. and Minimizing Interaural Crosstalk in Nearfield Monitoring by the Use of a Physical Barrier, AES Preprints 2420 A and 2420 B November 1986 ref ref Glasgal, Ralph, The Domestic Concert Hall, Stereophile magazine , July 1988 ref today a number of hardware and Virtual Studio Technology VST plug in makers offer Ambiophonic DSP. ref name Miller VST Robert E. Robin Miller III, User Guide to VST plug in Ambiophonic DSP, www.filmaker.com ref Ambiophonics eliminates crosstalk inherent in the conventional stereo triangle speaker placement, and thereby generates a speaker binaural soundfield that emulates headphone binaural recording binaural , and creates for the listener improved perception of reality of recorded auditory scenes. A second speaker pair can be added in back in order to enable 360 surround sound reproduction. Additional surround speakers may be used for hall ambience, including height, if desired. Ambiophonics, stereophonics, and human hearing In stereophonics, the reproduced sound is distorted by crosstalk, where signals from either speaker reach not only the intended ear, but the opposite ear, causing comb filter ing that distorts timbre of central voices, and creating false early reflections due to the delay of sound reaching the opposite ear. In addition, auditory images are bounded between left L and right R speakers, usually positioned at 30 with respect to the listener, thereby including 60 , only 1 6 of the horizontal circle, with the listener at the center. Human heari ... more details
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