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Sample records for vhf receivers aboard

  1. Design and Development of VHF Antennas for Space Borne Signal of Opportunity Receivers for Cubesat Platforms

    Science.gov (United States)

    Deshpande, Manohar; Piepmeier, Jeffrey

    2015-01-01

    Design and Development of VHF Antennas for Space Borne Signal of Opportunity Receivers for Cubesat Platforms. Space borne microwave remote sensors at VHF/UHF frequencies are important instruments to observe reflective properties of land surfaces through thick and heavy forestation on a global scale. One of the most cost effective ways of measuring land reflectivity at VHF/UHF frequencies is to use signals transmitted by existing communication satellites (operating at VHF/UHF band) as a signal of opportunity (SoOp) signal and passive receivers integrated with airborne/space borne platforms operating in the Low Earth Orbit (LEO). One of the critical components of the passive receiver is two antennas (one to receive only direct signal and other to receive only reflected signal) which need to have ideally high (>30dB) isolation. However, because of small size of host platforms and broad beam width of dipole antennas, achieving adequate isolation between two channels is a challenging problem and need to be solved for successful implementation of space borne SoOp technology for remote sensing. In this presentation a novel enabling VHF antenna technology for Cubesat platforms is presented to receive direct as well as reflected signal with needed isolation. The novel scheme also allows enhancing the gain of individual channels by factor of 2 without use of reflecting ground plane

  2. Design VHF Antennas for Space Borne Receivers for SmallSats

    Science.gov (United States)

    Deshpande, Manohar

    2017-01-01

    Space borne microwave remote sensors at VHF/UHF frequencies are important instruments to observe reflective properties of land surfaces through thick and heavy forestation on a global scale. One of the most cost effective ways of measuring land reflectivity at VHF/UHF frequencies is to use signals transmitted by existing communication satellites (operating at VHF/UHF band) as a signal of opportunity (SoOp) signal and passive receivers integrated with airborne/space borne platforms operating in the Low Earth Orbit (LEO). One of the critical components of the passive receiver is two antennas (one to receive only direct signal and other to receive only reflected signal) which need to have ideally high (>30dB) isolation. However, because of small size of host platforms and broad beam width of dipole antennas, achieving adequate isolation between two channels is a challenging problem and need to be solved for successful implementation of space borne SoOp technology for remote sensing. In this presentation a novel enabling VHF antenna technology for Cubesat platforms is presented to receive direct as well as reflected signal with needed isolation. The novel scheme also allows enhancing the gain of individual channels by factor of 2 without use of reflecting ground plane.

  3. Development Of VHF (240-270 MHz) Antennas For SoOp (Signal Of Opportunity) Receiver For 6u Cubesat Platforms

    Science.gov (United States)

    Joseph, A. T.; Deshpande, M.; O'Neill, P. E.; Miles, L.

    2016-01-01

    The main goal of this research is to design, fabricate, and test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a truly global direct surface soil moisture (SM) and RZSM measurement system (Figure 1) over a variety of land covers with limited density restrictions. In SoOp methodology, signals transmitted by already existing transmitters (known as transmitters of opportunity, in this case the Military Satellite Communication (MilSatCom) System's UHF Follow-On program) are utilized to measure properties of reflecting targets by recording reflected signals using a simple passive microwave receiver.

  4. Dicty_cDB: VHF264 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF264 (Link to dictyBase) - - - Contig-U16260-1 VHF264P (Link to Original site) VHF...264F 606 VHF264Z 693 VHF264P 1279 - - Show VHF264 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-C/VHF264Q.Seq.d/ Representative seq. ID VHF...264P (Link to Original site) Representative DNA sequence >VHF264 (VHF264Q) /CSM/VH/VHF2-C/VHF...DRRKNIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKV SGDMRYMSCRADEQERGITIKSSSVSLHFEMPKEDKLPAGCTS

  5. Dicty_cDB: VHF181 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF181 (Link to dictyBase) - - - Contig-U16260-1 VHF181P (Link to Original site) VHF...181F 610 VHF181Z 416 VHF181P 1006 - - Show VHF181 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF1-D/VHF181Q.Seq.d/ Representative seq. ID VHF...181P (Link to Original site) Representative DNA sequence >VHF181 (VHF181Q) /CSM/VH/VHF1-D/VHF...VKYKMVNFTIDQIRAIMDRRENIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKVSG DMRYMSCRADEQERGITIKSSSVSLHF

  6. Dicty_cDB: VHF777 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF777 (Link to dictyBase) - - - Contig-U16283-1 VHF777P (Link to Original site) VHF...777F 474 VHF777Z 669 VHF777P 1123 - - Show VHF777 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF7-D/VHF777Q.Seq.d/ Representative seq. ID VHF...777P (Link to Original site) Representative DNA sequence >VHF777 (VHF777Q) /CSM/VH/VHF7-D/VHF...PNIIGVEHYKVATDVQKILXRI*itsryychfryg*fi *rpksncipcs*dstflittirscprxhqygr*ir*tlrlyq

  7. Dicty_cDB: VHF354 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF354 (Link to dictyBase) - - - Contig-U16260-1 VHF354P (Link to Original site) VHF...354F 617 VHF354Z 721 VHF354P 1318 - - Show VHF354 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-C/VHF354Q.Seq.d/ Representative seq. ID VHF...354P (Link to Original site) Representative DNA sequence >VHF354 (VHF354Q) /CSM/VH/VHF3-C/VHF...no Acid sequence LSSAKKVKYKMVNFTIDQIRAIMDRRENIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKV SGD

  8. Dicty_cDB: VHF590 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF590 (Link to dictyBase) - - - Contig-U16306-1 VHF590P (Link to Original site) VHF...590F 115 VHF590Z 603 VHF590P 698 - - Show VHF590 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF5-D/VHF590Q.Seq.d/ Representative seq. ID VHF...590P (Link to Original site) Representative DNA sequence >VHF590 (VHF590Q) /CSM/VH/VHF5-D/VHF5...qlphvlrqlk*sqnfhkkylkkvqeqqq--- ---rwifhrwccfqsthdamyflyqxfgslsw*snlxrpkist*xfyhifghfw*rls*l ss*ipi*lqkwysyv

  9. Dicty_cDB: VHF536 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF536 (Link to dictyBase) - - - Contig-U16531-1 VHF536P (Link to Original site) VHF...536F 255 VHF536Z 685 VHF536P 920 - - Show VHF536 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF5-B/VHF536Q.Seq.d/ Representative seq. ID VHF...536P (Link to Original site) Representative DNA sequence >VHF536 (VHF536Q) /CSM/VH/VHF5-B/VHF5...ti*mlhliskvmtvh*mslslfyggyfl*lsi*llwnysig qvvvcliksikxerllkstmt--- ---*erlcl*ilxlvsichf

  10. Dicty_cDB: VHF730 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF730 (Link to dictyBase) - - - Contig-U15767-1 VHF730P (Link to Original site) VHF...730F 569 VHF730Z 718 VHF730P 1267 - - Show VHF730 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF7-B/VHF730Q.Seq.d/ Representative seq. ID VHF...730P (Link to Original site) Representative DNA sequence >VHF730 (VHF730Q) /CSM/VH/VHF7-B/VHF...QEKRIPVLNSMDANDSINKKA RISWPDGFKYFFVDNQAGDSESAKSGKNLPIQRDIELNWNGEAYEYSNSNYFPINGQXFN DVSYPV--- ---lhvvvvkxvhtlpvnvnqivhf

  11. Dicty_cDB: VHF649 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF649 (Link to dictyBase) - - - Contig-U11031-1 VHF649P (Link to Original site) VHF...649F 562 VHF649Z 671 VHF649P 1213 - - Show VHF649 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF6-C/VHF649Q.Seq.d/ Representative seq. ID VHF...649P (Link to Original site) Representative DNA sequence >VHF649 (VHF649Q) /CSM/VH/VHF6-C/VHF...PNTPPTIKIELPSQSILKPSGQLKK*x* Translated Amino Acid sequence (All Frames) Frame A: i*qlvchlsivlfhhqviyphvlklekhf

  12. Dicty_cDB: VHF527 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF527 (Link to dictyBase) - - - Contig-U16260-1 VHF527P (Link to Original site) VHF...527F 571 VHF527Z 456 VHF527P 1007 - - Show VHF527 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF5-B/VHF527Q.Seq.d/ Representative seq. ID VHF...527P (Link to Original site) Representative DNA sequence >VHF527 (VHF527Q) /CSM/VH/VHF5-B/VHF...AKKVKYKMVNFTIDQIRAIMDRRENIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKV SGDMRYMSCRADEQXRGITIKSSSVSLHF

  13. Dicty_cDB: VHF294 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF294 (Link to dictyBase) - - - Contig-U16441-1 VHF294P (Link to Original site) VHF...294F 573 VHF294Z 215 VHF294P 768 - - Show VHF294 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-D/VHF294Q.Seq.d/ Representative seq. ID VHF...294P (Link to Original site) Representative DNA sequence >VHF294 (VHF294Q) /CSM/VH/VHF2-D/VHF2...ssfst*scisfttfry*gfsdctfr*fhfn**RFWFNMEQCII QWVMFYS--- ---DCHVSIKKFFKWWQRLDRWCCXXXSCXXXSWWFWFPTFLRIQISNXXY*k

  14. Dicty_cDB: VHF690 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF690 (Link to dictyBase) - - - Contig-U11064-1 VHF690P (Link to Original site) VHF...690F 199 VHF690Z 419 VHF690P 598 - - Show VHF690 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF6-D/VHF690Q.Seq.d/ Representative seq. ID VHF...690P (Link to Original site) Representative DNA sequence >VHF690 (VHF690Q) /CSM/VH/VHF6-D/VHF6...vllksqsknqyl*hlikslidfinif*hgmhqiyhqrkkn*nq *k--- ---rrwfpr*rernhhfqlc*sts*rgcryw

  15. Dicty_cDB: VHF273 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF273 (Link to dictyBase) - - - Contig-U11514-1 VHF273P (Link to Original site) VHF...273F 644 VHF273Z 678 VHF273P 1302 - - Show VHF273 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-D/VHF273Q.Seq.d/ Representative seq. ID VHF...273P (Link to Original site) Representative DNA sequence >VHF273 (VHF273Q) /CSM/VH/VHF2-D/VHF...ctr*ccnvkdwchyssrl*syrs*ts*nrsifidr*iftsh*kdw**s llwfsnetr*skmcchcnwckhflwscckfstrnrrtwssssys*kywslly*fhrhlg

  16. Dicty_cDB: VHF243 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF243 (Link to dictyBase) - - - Contig-U16423-1 VHF243P (Link to Original site) VHF...243F 580 VHF243Z 334 VHF243P 894 - - Show VHF243 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-B/VHF243Q.Seq.d/ Representative seq. ID VHF...243P (Link to Original site) Representative DNA sequence >VHF243 (VHF243Q) /CSM/VH/VHF2-B/VHF2...AATCNAGATATTCCAGATTGGTTTGAAAAGATGG TACA sequence update 2002.10.25 Translated Amino Acid sequence ifihadkff*RISHF

  17. Dicty_cDB: VHF134 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF134 (Link to dictyBase) - - - Contig-U16260-1 VHF134P (Link to Original site) VHF...134F 533 VHF134Z 404 VHF134P 917 - - Show VHF134 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF1-B/VHF134Q.Seq.d/ Representative seq. ID VHF...134P (Link to Original site) Representative DNA sequence >VHF134 (VHF134Q) /CSM/VH/VHF1-B/VHF1...cid sequence LSSAKKVKYKMVNFTIDQIRAIMDRRENIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKV SGDMRYMSCRADEQERGITIKSSSVSLHFEMPKE

  18. Dicty_cDB: VHF892 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF892 (Link to dictyBase) - - - Contig-U16260-1 VHF892P (Link to Original site) VHF...892F 140 VHF892Z 417 VHF892P 537 - - Show VHF892 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF8-D/VHF892Q.Seq.d/ Representative seq. ID VHF...892P (Link to Original site) Representative DNA sequence >VHF892 (VHF892Q) /CSM/VH/VHF8-D/VHF8... Translated Amino Acid sequence TIKSSSVSLHFEMPXEDKLPAGCTSHEFLINLIDSPSHVDFS--- ---ELTASPNILEPIYLVEITAPENAIGGI

  19. Dicty_cDB: VHF479 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF479 (Link to dictyBase) - - - Contig-U11426-1 VHF479P (Link to Original site) VHF...479F 629 VHF479Z 691 VHF479P 1300 - - Show VHF479 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF4-D/VHF479Q.Seq.d/ Representative seq. ID VHF...479P (Link to Original site) Representative DNA sequence >VHF479 (VHF479Q) /CSM/VH/VHF4-D/VHF...EKNPQEWRWSGGFFVDSISDYVVKSRNTERPDHDSLLF HVNIKEKQGTHFIRIPLSSKESPPYIIQNDTQFKISFFQRDSPENIDYIEPKEKLCYGWD EPSAEYVL

  20. Dicty_cDB: VHF754 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF754 (Link to dictyBase) - - - Contig-U16531-1 VHF754P (Link to Original site) VHF...754F 526 VHF754Z 624 VHF754P 1130 - - Show VHF754 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF7-C/VHF754Q.Seq.d/ Representative seq. ID VHF...754P (Link to Original site) Representative DNA sequence >VHF754 (VHF754Q) /CSM/VH/VHF7-C/VHF...ixnkmqwlkmlqvk*killk*ekvvslgiiftipf--- ---flvsichfnchc*itfccsrwnnlxllxfldsryllqw*

  1. Dicty_cDB: VHF461 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF461 (Link to dictyBase) - - - Contig-U11551-1 VHF461P (Link to Original site) VHF...461F 646 VHF461Z 261 VHF461P 887 - - Show VHF461 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF4-C/VHF461Q.Seq.d/ Representative seq. ID VHF...461P (Link to Original site) Representative DNA sequence >VHF461 (VHF461Q) /CSM/VH/VHF4-C/VHF4...TTAAATTATTAAAAATAGTAAATAAAAAAAA sequence update 2002.10.25 Translated Amino Acid sequence fyfifenfkthfhiiffl

  2. Dicty_cDB: VHF781 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF781 (Link to dictyBase) - - - Contig-U16440-1 VHF781P (Link to Original site) VHF...781F 452 VHF781Z 680 VHF781P 1112 - - Show VHF781 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF7-D/VHF781Q.Seq.d/ Representative seq. ID VHF...781P (Link to Original site) Representative DNA sequence >VHF781 (VHF781Q) /CSM/VH/VHF7-D/VHF...vlkmmmlkf*xixftr*r Frame C: glldinkleeiik*rfhlfylfl*rlllayhfhkilfqlisktaligsnfnhyiqikmim y*l*iqdqrmf*kdqqmvv

  3. Dicty_cDB: VHF435 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF435 (Link to dictyBase) - - - Contig-U16260-1 VHF435P (Link to Original site) VHF...435F 616 VHF435Z 703 VHF435P 1299 - - Show VHF435 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF4-B/VHF435Q.Seq.d/ Representative seq. ID VHF...435P (Link to Original site) Representative DNA sequence >VHF435 (VHF435Q) /CSM/VH/VHF4-B/VHF...AKKVKYKMVNFTIDQIRAIMDRRENIRNMSVIAHVDHGKTTLSDSLIQRAGIIADKV SGDMRYMSCRADEQERGITIKSSSVSLHF

  4. Dicty_cDB: VHF553 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF553 (Link to dictyBase) - - - Contig-U16433-1 VHF553P (Link to Original site) VHF...553F 122 VHF553Z 533 VHF553P 635 - - Show VHF553 Library VH (Link to library) Clone ID VHF... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF5-C/VHF553Q.Seq.d/ Representative seq. ID VHF...553P (Link to Original site) Representative DNA sequence >VHF553 (VHF553Q) /CSM/VH/VHF5-C/VHF5...ed Amino Acid sequence syhfylfiy*IIIYLLNYYLLSCVNYLPINFNILYIY--- ---YVINLTLDGDNVNGFPKTVTVKPAPSXEQXYAEGEGLVKVF

  5. Dicty_cDB: VHF163 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF163 (Link to dictyBase) - - - Contig-U11129-1 VHF163P (Link to Original site) VHF1...63F 611 VHF163Z 654 VHF163P 1245 - - Show VHF163 Library VH (Link to library) Clone ID VHF1...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF1-C/VHF163Q.Seq.d/ Representative seq. ID VHF1...63P (Link to Original site) Representative DNA sequence >VHF163 (VHF163Q) /CSM/VH/VHF1-C/VHF1...nt alignments: (bits) Value VHF163 (VHF163Q) /CSM/VH/VHF1-C/VHF163Q.Seq.d/ 2357 0.0 VHM584 (VHM584Q) /CSM/VH

  6. Dicty_cDB: VHF444 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available (Link to library) VHF444 (Link to dictyBase) - G20601 DDB0204337 Contig-U12392-1 VHF444P (Link to Original...site) VHF444F 579 VHF444Z 213 VHF444P 772 - - Show VHF444 Library VH (Link to library) Clone ID VHF444 (Link...tsukuba.ac.jp/CSM/VH/VHF4-B/VHF444Q.Seq.d/ Representative seq. ID VHF444P (Link to Original site) Representative...Representative DNA sequence >VHF444 (VHF444Q) /CSM/VH/VHF4-B/VHF444Q.Seq.d/ CAAAAGAAATAAATAATTATGCCATCA...significant alignments: (bits) Value VHF444 (VHF444Q) /CSM/VH/VHF4-B/VHF444Q.Seq.d/ 1479 0.0 VHA836 (VHA836Q)

  7. Dicty_cDB: VHF338 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF338 (Link to dictyBase) - - - Contig-U14303-1 VHF338P (Link to Original site) VHF3...38F 208 VHF338Z 685 VHF338P 873 - - Show VHF338 Library VH (Link to library) Clone ID VHF3... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-B/VHF338Q.Seq.d/ Representative seq. ID VHF3...38P (Link to Original site) Representative DNA sequence >VHF338 (VHF338Q) /CSM/VH/VHF3-B/VHF3...significant alignments: (bits) Value VHF338 (VHF338Q) /CSM/VH/VHF3-B/VHF338Q.Seq.d/ 1296 0.0 VHK267 (VHK267Q

  8. Dicty_cDB: VHF394 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF394 (Link to dictyBase) - - - Contig-U16260-1 VHF394P (Link to Original site) VHF3...94F 563 VHF394Z 417 VHF394P 960 - - Show VHF394 Library VH (Link to library) Clone ID VHF3... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-D/VHF394Q.Seq.d/ Representative seq. ID VHF3...94P (Link to Original site) Representative DNA sequence >VHF394 (VHF394Q) /CSM/VH/VHF3-D/VHF3...nt alignments: (bits) Value VHF394 (VHF394Q) /CSM/VH/VHF3-D/VHF394Q.Seq.d/ 1776 0

  9. Dicty_cDB: VHF340 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF340 (Link to dictyBase) - - - Contig-U11939-1 VHF340P (Link to Original site) VHF3...40F 113 VHF340Z 506 VHF340P 599 - - Show VHF340 Library VH (Link to library) Clone ID VHF3... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-B/VHF340Q.Seq.d/ Representative seq. ID VHF3...40P (Link to Original site) Representative DNA sequence >VHF340 (VHF340Q) /CSM/VH/VHF3-B/VHF3...Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF340 (VHF340Q) /CSM/VH/VHF3-B/VHF3

  10. Dicty_cDB: VHF329 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF329 (Link to dictyBase) - - - Contig-U16260-1 VHF329P (Link to Original site) VHF3...29F 618 VHF329Z 633 VHF329P 1231 - - Show VHF329 Library VH (Link to library) Clone ID VHF3...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-B/VHF329Q.Seq.d/ Representative seq. ID VHF3...29P (Link to Original site) Representative DNA sequence >VHF329 (VHF329Q) /CSM/VH/VHF3-B/VHF3...s CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF329 (VHF329Q) /CSM/VH/VHF3

  11. Dicty_cDB: VHF187 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF187 (Link to dictyBase) - - - Contig-U16363-1 VHF187P (Link to Original site) VHF1...87F 549 VHF187Z 707 VHF187P 1236 - - Show VHF187 Library VH (Link to library) Clone ID VHF1...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF1-D/VHF187Q.Seq.d/ Representative seq. ID VHF1...87P (Link to Original site) Representative DNA sequence >VHF187 (VHF187Q) /CSM/VH/VHF1-D/VHF1...* Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF187 (VHF1

  12. Dicty_cDB: VHF368 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF368 (Link to dictyBase) - - - Contig-U12673-1 VHF368P (Link to Original site) VHF3...68F 597 VHF368Z 746 VHF368P 1323 - - Show VHF368 Library VH (Link to library) Clone ID VHF3...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-C/VHF368Q.Seq.d/ Representative seq. ID VHF3...68P (Link to Original site) Representative DNA sequence >VHF368 (VHF368Q) /CSM/VH/VHF3-C/VHF3...ikfpknkii*nki k*nkiky Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF368 (VHF3

  13. Dicty_cDB: VHF348 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF348 (Link to dictyBase) - - - Contig-U13926-1 VHF348P (Link to Original site) VHF3...48F 539 VHF348Z 473 VHF348P 992 - - Show VHF348 Library VH (Link to library) Clone ID VHF3... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-B/VHF348Q.Seq.d/ Representative seq. ID VHF3...48P (Link to Original site) Representative DNA sequence >VHF348 (VHF348Q) /CSM/VH/VHF3-B/VHF3...ksxvlmliltck Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF3

  14. Dicty_cDB: VHF312 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF312 (Link to dictyBase) - - - Contig-U15897-1 VHF312P (Link to Original site) VHF3...12F 543 VHF312Z 483 VHF312P 1006 - - Show VHF312 Library VH (Link to library) Clone ID VHF3...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-A/VHF312Q.Seq.d/ Representative seq. ID VHF3...12P (Link to Original site) Representative DNA sequence >VHF312 (VHF312Q) /CSM/VH/VHF3-A/VHF3... 4.0 %: extracellular, including cell wall 4.0 %: plasma membrane 4.0 %: peroxisomal >> prediction for VHF31

  15. Dicty_cDB: VHF375 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF375 (Link to dictyBase) - - - Contig-U16260-1 VHF375P (Link to Original site) VHF3...75F 432 VHF375Z 670 VHF375P 1082 - - Show VHF375 Library VH (Link to library) Clone ID VHF3...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-D/VHF375Q.Seq.d/ Representative seq. ID VHF3...75P (Link to Original site) Representative DNA sequence >VHF375 (VHF375Q) /CSM/VH/VHF3-D/VHF3...pperekv*pqksqiltnstknskqfkshxsfqr*xsnlkk Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF3

  16. Dicty_cDB: VHF190 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available F0-ATPase putative regulatory protein IF1 (if1) mRNA, complete cds; nuclear gene for mitochondrial produc...VH (Link to library) VHF190 (Link to dictyBase) - - - Contig-U12594-1 - (Link to Original site) VHF1...90F 581 - - - - - - Show VHF190 Library VH (Link to library) Clone ID VHF190 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF1-D/VHF190Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF190 (VHF190Q) /CSM/VH/VHF1-D/VHF190Q.Seq.d/ ATTTTTCATTTTAAAAA

  17. Dicty_cDB: VHF331 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF331 (Link to dictyBase) - - - - - (Link to Original site) VHF3...31F 609 - - - - - - Show VHF331 Library VH (Link to library) Clone ID VHF331 (Link to dictyBase) Atlas ID... - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-B/VHF3...31Q.Seq.d/ Representative seq. ID - (Link to Original site) Representative DNA sequence >VHF3...31 (VHF331Q) /CSM/VH/VHF3-B/VHF331Q.Seq.d/ AACTCTCGAGTGCAAAAAAAGTAAAGTACAAAATGGTTAATTTCA

  18. Dicty_cDB: VHF709 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF709 (Link to dictyBase) - - - Contig-U15897-1 - (Link to Original site) - - VHF...709Z 602 - - - - Show VHF709 Library VH (Link to library) Clone ID VHF709 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF7-A/VHF709Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF709 (VHF709Q) /CSM/VH/VHF7-A/VHF709Q.Seq.d/ XXXXXXXXXXCGTCCAA...vestir Frame B: ---sknfttrsrlqlccsfnglxpr**rw*tnrqhyhg*cksiwsssfnlsryyw*yrcs ilpqiq*kwchhsnlpiw*wsflyhf

  19. Dicty_cDB: VHF236 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF236 (Link to dictyBase) - - - Contig-U14303-1 - (Link to Original site) - - VHF...236Z 611 - - - - Show VHF236 Library VH (Link to library) Clone ID VHF236 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF2-B/VHF236Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF236 (VHF236Q) /CSM/VH/VHF2-B/VHF236Q.Seq.d/ XXXXXXXXXXTGCCATT...VQKISQELKHLT*tfvsylvlk Frame B: ---plvicc*ninvlhfveilsxhglay*xhcfplvlv*fqilsrmiqs

  20. Dicty_cDB: VHF140 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF140 (Link to dictyBase) - - - Contig-U15309-1 - (Link to Original site) - - VHF...140Z 518 - - - - Show VHF140 Library VH (Link to library) Clone ID VHF140 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF1-B/VHF140Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF140 (VHF140Q) /CSM/VH/VHF1-B/VHF140Q.Seq.d/ XXXXXXXXXXCCGATAA...EDYINMQIKQLENSENSQELIQKLNEHLSEYKASVEEIKHNVQNN Frame C: ---iixvtlmlflqngilhfigviil

  1. Dicty_cDB: VHF507 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF507 (Link to dictyBase) - - - Contig-U11594-1 - (Link to Original site) - - VHF...507Z 541 - - - - Show VHF507 Library VH (Link to library) Clone ID VHF507 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF5-A/VHF507Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF507 (VHF507Q) /CSM/VH/VHF5-A/VHF507Q.Seq.d/ XXXXXXXXXXTACCAAT...nvhsmiwihvglxlvigx*sncfvttsfikst mmvllcstftmllkpsixwivvsmkkyf*clemnxhfw*sviki*knv

  2. Dicty_cDB: VHF321 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF321 (Link to dictyBase) - - - Contig-U16260-1 - (Link to Original site) VHF...321F 617 - - - - - - Show VHF321 Library VH (Link to library) Clone ID VHF321 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF3-A/VHF321Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF321 (VHF321Q) /CSM/VH/VHF3-A/VHF321Q.Seq.d/ AACTCTCGAGTGCAAAA...VIAHVDHGKTTLSDSLIQRAGIIADKV SGDMRYMSCRADEQERGITIKSSSVSLHFEMPKEDKLPAGCTSHEFLINLIDSPGHVDFS SEVTAALRVTDGALVVIDC

  3. Dicty_cDB: VHF866 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF866 (Link to dictyBase) - - - Contig-U16600-1 - (Link to Original site) - - VHF...866Z 388 - - - - Show VHF866 Library VH (Link to library) Clone ID VHF866 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF8-C/VHF866Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF866 (VHF866Q) /CSM/VH/VHF8-C/VHF866Q.Seq.d/ XXXXXXXXXXAAGCAGC...Frame C: ---qhnnifklafptiknftgvpmxfvmtnegdnlgnftvkthfakffstyyscgeaghh yfdsccn*y*qkqgckfhs*h*xkssrr*lcfxqnwfi

  4. Dicty_cDB: VHF155 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF155 (Link to dictyBase) - - - - VHF155P (Link to Original site) VHF155F 587 VHF1...55Z 643 VHF155P 1210 - - Show VHF155 Library VH (Link to library) Clone ID VHF155 (Link... to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF1...-C/VHF155Q.Seq.d/ Representative seq. ID VHF155P (Link to... Original site) Representative DNA sequence >VHF155 (VHF155Q) /CSM/VH/VHF1-C/VHF155Q.Seq.d/ ATTCTCGATACTGGAA

  5. Dicty_cDB: VHF392 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF392 (Link to dictyBase) - - - - VHF392P (Link to Original site) VHF392F 568 VHF3...92Z 375 VHF392P 923 - - Show VHF392 Library VH (Link to library) Clone ID VHF392 (Link ...to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3...-D/VHF392Q.Seq.d/ Representative seq. ID VHF392P (Link to ...Original site) Representative DNA sequence >VHF392 (VHF392Q) /CSM/VH/VHF3-D/VHF392Q.Seq.d/ AACTCTCGAGTGCAAAA

  6. Dicty_cDB: VHF366 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF366 (Link to dictyBase) - - - Contig-U12131-1 | Contig-U13633-1 VHF3...66P (Link to Original site) VHF366F 590 VHF366Z 544 VHF366P 1114 - - Show VHF366 Library VH (Link to library) Clone ID VHF3...131-1 | Contig-U13633-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-C/VHF3...66Q.Seq.d/ Representative seq. ID VHF366P (Link to Original site) Representative DNA sequence >VHF366 (VHF3...66Q) /CSM/VH/VHF3-C/VHF366Q.Seq.d/ AATAATTTATTATTATTATTAATAAGTAATAGAAATAAAAGATGGAACCAATTCCAGATA

  7. Dicty_cDB: VHF310 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF310 (Link to dictyBase) - - - Contig-U16260-1 - (Link to Original site) - - VHF3...10Z 625 - - - - Show VHF310 Library VH (Link to library) Clone ID VHF310 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF3-A/VHF310Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF310 (VHF310Q) /CSM/VH/VHF3-A/VHF310Q.Seq.d/ XXXXXXXXXXTCGTCAA...omology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VHF310 (VHF310Q) /CSM/VH/VHF3-A/VHF3

  8. Dicty_cDB: VHF315 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF315 (Link to dictyBase) - G20600 DDB0169270 Contig-U12450-1 VHF3...15P (Link to Original site) VHF315F 216 VHF315Z 353 VHF315P 549 - - Show VHF315 Library VH (Link to library) Clone ID VHF3...ontig-U12450-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF3-A/VHF3...15Q.Seq.d/ Representative seq. ID VHF315P (Link to Original site) Representative DNA sequence >VHF315 (VHF315Q) /CSM/VH/VHF3...-A/VHF315Q.Seq.d/ ATTAAAAAACTTCTTACTTGGACACCCCTTTTATATATATAAATAAAAACTTCTAAATAT AAATCCCA

  9. Dicty_cDB: VHF381 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF381 (Link to dictyBase) - - - Contig-U16508-1 - (Link to Original site) - - VHF3...81Z 645 - - - - Show VHF381 Library VH (Link to library) Clone ID VHF381 (Link to dicty...iol.tsukuba.ac.jp/CSM/VH/VHF3-D/VHF381Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >VHF381 (VHF381Q) /CSM/VH/VHF3-D/VHF381Q.Seq.d/ XXXXXXXXXXCAACCAA...ignments: (bits) Value VHF381 (VHF381Q) /CSM/VH/VHF3-D/VHF381Q.Seq.d/ 1223 0.0 VHP767 (VHP767Q) /CSM/VH/VHP7

  10. Dicty_cDB: VHF210 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF210 (Link to dictyBase) - - - Contig-U12400-1 | Contig-U16431-1 VHF...210P (Link to Original site) VHF210F 613 VHF210Z 636 VHF210P 1229 - - Show VHF210 Library VH (Link to library) Clone ID VHF...400-1 | Contig-U16431-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-A/VHF...210Q.Seq.d/ Representative seq. ID VHF210P (Link to Original site) Representative DNA sequence >VHF210 (VHF...210Q) /CSM/VH/VHF2-A/VHF210Q.Seq.d/ AATAAAATGATAAGATCATCAATAAAAAATAAAATAACAACAACAAAAAGTTTATCATGT

  11. Dicty_cDB: VHF575 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF575 (Link to dictyBase) - - - Contig-U15481-1 | Contig-U15981-1 VHF...575P (Link to Original site) VHF575F 586 VHF575Z 397 VHF575P 963 - - Show VHF575 Library VH (Link to library) Clone ID VHF...81-1 | Contig-U15981-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF5-D/VHF...575Q.Seq.d/ Representative seq. ID VHF575P (Link to Original site) Representative DNA sequence >VHF575 (VHF...575Q) /CSM/VH/VHF5-D/VHF575Q.Seq.d/ ATAATAATACAAAGAAGAAATGAAAAATATAAATAATAAAATTTTAAAGATTTTTATTCT

  12. Dicty_cDB: VHF296 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF296 (Link to dictyBase) - G23392 DDB0187414 Contig-U12449-1 VHF...296P (Link to Original site) VHF296F 241 VHF296Z 482 VHF296P 703 - - Show VHF296 Library VH (Link to library) Clone ID VHF...ontig-U12449-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-D/VHF...296Q.Seq.d/ Representative seq. ID VHF296P (Link to Original site) Representative DNA sequence >VHF296 (VHF296Q) /CSM/VH/VHF...2-D/VHF296Q.Seq.d/ GATTATCAGAAAGATTACATTATGAAATTATACCAGATTGTATTAAAATTATTGAAAGCT CAAAACAA

  13. Dicty_cDB: VHF436 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF436 (Link to dictyBase) - - - - VHF436P (Link to Original site) VHF436F 618 VHF...436Z 699 VHF436P 1297 - - Show VHF436 Library VH (Link to library) Clone ID VHF436 (Link... to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF...4-B/VHF436Q.Seq.d/ Representative seq. ID VHF436P (Link to... Original site) Representative DNA sequence >VHF436 (VHF436Q) /CSM/VH/VHF4-B/VHF436Q.Seq.d/ AACTCTCGAGTGCAAA

  14. Dicty_cDB: VHF158 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF158 (Link to dictyBase) - - - - VHF158P (Link to Original site) VHF158F 608 VHF...158Z 693 VHF158P 1281 - - Show VHF158 Library VH (Link to library) Clone ID VHF158 (Link... to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF...1-C/VHF158Q.Seq.d/ Representative seq. ID VHF158P (Link to... Original site) Representative DNA sequence >VHF158 (VHF158Q) /CSM/VH/VHF1-C/VHF158Q.Seq.d/ AACTCTCGAGTGCAAA

  15. Dicty_cDB: VHF847 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF847 (Link to dictyBase) - - - Contig-U15351-1 | Contig-U16514-1 VHF...847P (Link to Original site) VHF847F 478 VHF847Z 709 VHF847P 1167 - - Show VHF847 Library VH (Link to library) Clone ID VHF...351-1 | Contig-U16514-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF8-B/VHF...847Q.Seq.d/ Representative seq. ID VHF847P (Link to Original site) Representative DNA sequence >VHF847 (VHF...847Q) /CSM/VH/VHF8-B/VHF847Q.Seq.d/ TATGATGTTCCACTTATAATTCAAACGGTTGCCAATAATAAATCAACAAAACTCANTCTT

  16. Dicty_cDB: VHF272 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF272 (Link to dictyBase) - - - Contig-U15754-1 VHF272P (Link to Original site) VHF...272F 515 VHF272Z 603 VHF272P 1098 - - Show VHF272 Library VH (Link to library) Clone ID VHF...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHF2-C/VHF272Q.Seq.d/ Representative seq. ID VHF...272P (Link to Original site) Representative DNA sequence >VHF272 (VHF272Q) /CSM/VH/VHF2-C/VHF...id sequence (All Frames) Frame A: ixfssq**wnkkd*mihy*eiligrigvpm*vidngqlfvkimvvnhgptfhtimldhvh idgqrivlvdfvidfkifv*v*hf

  17. Very Compact and Broadband Active Antenna for VHF Band Applications

    Directory of Open Access Journals (Sweden)

    Y. Taachouche

    2012-01-01

    Full Text Available An active receiving antenna with small size consisting of a monopole loaded with a transistor bipolar is presented in this paper. A transistor is used in order to miniaturize the receiving active antenna size in VHF band. The vertical size of the structure is equal to λ/175, where λ is the wavelength at the lower frequency of the bandwidth. Despite the very small size of the antenna, the frequency bandwidth is very wide and the gain is suitable for FM application with sensitive receivers.

  18. PMSE Observations With the Tri-Static EISCAT VHF Radars

    Science.gov (United States)

    Mann, I.; Tjulin, A.; Häggström, I.

    2013-12-01

    The polar mesospheric summer echoes (PMSE) are generated in the ionosphere at roughly 80 to 90 altitude by electron irregularities in the presence of charged solid particles and PMSE are most likely observed when ice particles form onto nanodust. PMSE formation is an important part in understanding mesospheric processes, but is also an interesting example for dusty plasma phenomena occurring in space. To investigate the phenomena that lead to formation of PMSE it is helpful to study the radar reflectivity of the mesosphere at different angles. PMSE were previously studied at different aspect angles in order to better understand the scattering process. Another way is observing PMSE from multiple sites simultaneously. During this summer the EISCAT radars that are located in Northern Scandinavia could for the first time be used for tri-static observations in the VHF band and we carried out observations during three subsequent days in June 2013. The radar signal was transmitted in zenith direction with the EISCAT VHF antenna near Tromsø (69.59 deg N, 19.23 deg E) and the scattered signal was measured from Tromsø, Kiruna (67.86 deg N, 20.44 deg E) and Sodankylä (67.36 deg N, 26.63 deg E). Zenith observations were simultaneously carried out with the Tromsø UHF radar (933 MHz). Other groups have previously reported the observations of PMSE simultaneously with the EISCAT VHF and UHF radars, but with a much lower occurrence rate for the UHF. UHF observations made during this campaign are dominated by incoherent scatter. The VHF system in Tromsø detected PMSE for a large fraction of the observation time. The VHF receivers in Kiruna and Sodankylä were pointed at typical PMSE heights above the Tromsø transmitter and detected radar reflections at the same time and altitude as the Tromsø radar. These observations are among the first tri-static observations of PMSE. Preliminary results from the campaign will be presented and discussed.

  19. Dicty_cDB: VHF476 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available uences producing significant alignments: (bits) Value VHF476 (VHF476Q) /CSM/VH/VHF4-D/VHF476Q.Seq.d/ 198 2e-...46 own update 2003.10.17 Homology vs DNA Score E Sequences producing significant alignments: (bits) Value...e 2008.10.29 Homology vs Protein Score E Sequences producing significant alignments: (bits) Value (Q54AX5) R

  20. 47 CFR 80.911 - VHF transmitter.

    Science.gov (United States)

    2010-10-01

    ... MARITIME SERVICES Compulsory Radiotelephone Installations for Small Passenger Boats § 80.911 VHF..., measured at the power input terminals to the transmitter, and the output power of the transmitter, terminated in a matching artificial load, must be measured at the end of 10 minutes of continuous operation...

  1. First wind shear observation in PMSE with the tristatic EISCAT VHF radar

    Science.gov (United States)

    Mann, I.; Häggström, I.; Tjulin, A.; Rostami, S.; Anyairo, C. C.; Dalin, P.

    2016-11-01

    The Polar Summer Mesosphere has the lowest temperatures that occur in the entire Earth system. Water ice particles below the optically observable size range participate there in the formation of strong radar echoes (Polar Mesospheric Summer Echoes, PMSE). To study PMSE we carried out observations with the European Incoherent Scatter (EISCAT) VHF and EISCAT UHF radar simultaneously from a site near Tromsø (69.58°N, 19.2272°E) and observed VHF backscattering also with the EISCAT receivers in Kiruna (67.86°N, 20.44°E) and Sodankylä (67.36°N, 26.63°E). This is one of the first tristatic measurements with EISCAT VHF, and we therefore describe the observations and geometry in detail. We present observations made on 26 June 2013 from 7:00 to 13:00 h UT where we found similar PMSE patterns with all three VHF receivers and found signs of wind shear in PMSE. The observations suggest that the PMSE contains sublayers that move in different directions horizontally, and this points to Kelvin-Helmholtz instability possibly playing a role in PMSE formation. We find no signs of PMSE in the UHF data. The electron densities that we derive from observed incoherent scatter at UHF are at PMSE altitudes close to the noise level but possibly indicate reduced electron densities directly above the PMSE.

  2. Dicty_cDB: VHF729 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ences producing significant alignments: (bits) Value VHF729 (VHF729Q) /CSM/VH/VHF...4-A/CHC421Q.Seq.d/ 139 9e-33 own update 2002.12.27 Homology vs DNA Score E Sequences producing significant alignments: (bits) Value... 139 2e-29 1 dna update 2008.10.31 Homology vs Protein Score E Sequences producing significant alignments: (bits) Value

  3. From ultrafast spectroscopy to bidirectional molecular switches: DHA/VHF

    Science.gov (United States)

    Schmidhammer, U.; De Waele, V.; Buntinx, G.; Riedle, E.

    The photoconversion from dihydroazulene (DHA) to vinylheptafulvene (VHF) is governed by two mechanisms: The ring opening proceeds on the excited energy surface on the picosecond time scale. It is followed by an intemal conversion to the VHF ground state that is accelerated by the presence of a conical intersection in the case of cyclopenta-DHA. This conical intersection hinders the photoinduced back reaction from the final VHF products. However, we successfully photoconverted the cyanophenyl-VHF-cis back to the DHA with a second delayed pulse. This opens the route to the development of bistable DHAs.

  4. An analysis on the mid-latitude scintillation and coherence frequency bandwidth using transionospheric VHF signals

    Energy Technology Data Exchange (ETDEWEB)

    Juang, Zhen [Los Alamos National Laboratory; Roussel-dupre, Robert [Los Alamos National Laboratory

    2008-01-01

    An analysis was perfonned on the mid-latitude scintillation and coherence frequency bandwidth (Fcoh) using transionospheric VHF signal data. The data include 1062 events spanning from November 1997 to June 2002. Each event records FORTE satellite received VHF signals from LAPP located at Los Alamos, New Mexico. Fcohs were derived to study scintillation characteristics on diurnal and seasonal variations, as well as changes due to solar and geomagnetic activities. Comparisons to the VHFIUHF coherence frequency bandwidth studies previously reported at equatorial and mid-latitude regions are made using a 4th power frequency dependence relationship. Furthennore, a wideband ionospheric scintillation model, WBMOD, was used to estimate Fcohs and compared with our VHF Fcoh values. Our analysis indicates mid-latitude scintillation characteristics that are not previously revealed. At the VHF bottom frequency range (3035 MHz), distinguished smaller Fcohs are found in time period from sunset to midnight, in wann season from May to August, and in low solar activity years. The effects of geomagnetic storm activity on Fcoh are characterized by a sudden transition at a Kp index of 50-60. Comparisons with median Fcohs estimated from other studies validated our VHF Fcohs for daytime while an order of magnitude larger Fcohs are found for nighttime, implying a time-dependent issue in applying the 4th order power relationship. Furthermore, comparisons with WBMOD-estimated Fcohs indicated generally matched median scintillation level estimates while differences do exist for those events undergoing high geomagnetic stonn activity which may imply underestimates of scintillation level by the WBMOD in the mid-latitude regions.

  5. Dicty_cDB: VHF823 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available uences producing significant alignments: (bits) Value VHF823 (VHF823Q) /CSM/VH/VH...186Q.Seq.d/ 86 1e-16 own update 2009. 4. 4 Homology vs DNA Score E Sequences producing significant alignments: (bits) Value...-13 1 dna update 2008.10.31 Homology vs Protein Score E Sequences producing significant alignments: (bits) Value

  6. Measurements methodology for evaluation of Digital TV operation in VHF high-band

    Science.gov (United States)

    Pudwell Chaves de Almeida, M.; Vladimir Gonzalez Castellanos, P.; Alfredo Cal Braz, J.; Pereira David, R.; Saboia Lima de Souza, R.; Pereira da Soledade, A.; Rodrigues Nascimento Junior, J.; Ferreira Lima, F.

    2016-07-01

    This paper describes the experimental setup of field measurements carried out for evaluating the operation of the ISDB-TB (Integrated Services Digital Broadcasting, Terrestrial, Brazilian version) standard digital TV in the VHF-highband. Measurements were performed in urban and suburban areas in a medium-sized Brazilian city. Besides the direct measurements of received power and environmental noise, a measurement procedure involving the injection of Gaussian additive noise was employed to achieve the signal to noise ratio threshold at each measurement site. The analysis includes results of static reception measurements for evaluating the received field strength and the signal to noise ratio thresholds for correct signal decoding.

  7. Dicty_cDB: VHF145 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHF145 (Link to dictyBase) - - - Contig-U15430-1 VHF145E (Link...) Clone ID VHF145 (Link to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U15430-1 Ori...ology vs DNA Score E Sequences producing significant alignments: (bits) Value N AC116984 |AC116984.2 Dictyos... theta DNA for complete sequence of nucleomorph chromosome 2. 48 2e-07 2 ES451909 | PREDICTED: similar to PI...al 16.0 %: nuclear 8.0 %: vacuolar 8.0 %: endoplasmic reticulum 4.0 %: cytoskeletal >> prediction for VHF145

  8. Broadband VHF observations for lightning impulses from a small satellite SOHLA-1 (Maido 1)

    Science.gov (United States)

    Morimoto, T.; Kikuchi, H.; Ushio, T.; Kawasaki, Z.; Hidekazu, H.; Aoki, T.

    2009-12-01

    Lightning Research Group of Osaka University (LRG-OU) has been developing VHF Broadband Digital Interferometer (DITF) to image precise lightning channels and monitor lightning activity widely. The feature of broadband DITF is its ultrawide bandwidth (from 25MHz to 100MHz) and implicit redundancy for estimating VHF source location. LRG-OU considers an application of the broadband DITF to the spaceborne measurement system and joins the SOHLA (Space Oriented Higashi-Osaka Leading Associate) satellite project. The SOHLA satellite project represents a technology transfer program to expand the range of the space development community in Japan. The objective is to get SMEs (Small and Medium sized manufacturing Enterprises) involved in small space projects and new space technologies. Under the cooperative agreement, JAXA (Japan Aerospace Exploration Agency) intends to contribute to socio-economic development by returning its R&D results to society, and SOHLA tries to revitalize the local economy through the commercialization of versatile small satellites. According to the agreement, JAXA provides SOHLA its technical information on small satellites and other technical assistance for the development of the small satellites, SOHLA-1. The prime objective of the SOHLA-1 program is to realize low-cost and short term development of a microsatellite which utilizes the components and bus technologies of JAXA’s MicroLabSat. SOHLA-1 is a spin-stabilized microsatellite of MicroLabSat heritage (about 50 kg). The spin axis is fixed to inertial reference frame. The spin axis (z-axis) lies in the plane containing the solar direction and the normal to the orbital plane. LRG-OU takes responsibility for a science mission of SOHLA-1. To examine the feasibility of the DITF receiving VHF lightning impulses in space, LRG-OU proposes the BMW (Broadband Measurement of Waveform for VHF Lightning Impulses). BMW consists of a single pair of an antenna, a band-pass filter, an amplifier, and an

  9. Broadband Grounded Vertical Antennas for 30-180 MHZ (VHF)

    Science.gov (United States)

    2013-10-18

    antennas are well known for their broadband gain (monocone, bicone ) but are never combined with a monopole. An eccentric combination of broadband...DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Broadband Grounded Vertical Antennas For 30-180 MZH (VHF) 5a. CONTRACT NUMBER 5b...18 Attorney Docket No. 102536 1 of 17 BROADBAND GROUNDED VERTICAL ANTENNAS FOR 30-180 MHZ (VHF) STATEMENT OF GOVERNMENT INTEREST

  10. Anechoic chamber for VHF and UHF bands

    Science.gov (United States)

    Morikawa, Takao; Sugiura, Akira; Harima, Katsushige; Masuzawa, Hiroshi

    1995-06-01

    Built in 1969, the anechoic chamber of CRL has been used to the fullest by researchers in many fields such as EMI, EMC, antenna design, standard of electric field intensity, and type approval testing. In particular, in the early days of space development in Japan, many satellite-born antennas were developed in this anechoic chamber. However, a quarter of a century has passed since its construction and deteriorated performance due to superannuation sometimes caused difficulties in experiments conducted in the chamber. In 1993, CRL constructed a Measuring Facility for Radio Research (MFRR) and the anechoic chamber for VHF-UHF bands was remodeled as one of the sub-facilities of MFRR. The remodeling work included full replacement of the electromagnetic shielding, absorbers and measurement system. Since the remodeled anechoic chamber is being used not only for EMI tests but also for other purposes, a full-anechoic chamber has been adopted. In addition the chamber has been designed for the frequency range between 30 MHz and 10 GHz. After the remodeling work, the performance of the chamber is greatly improved. The average shielding factor is better than 85 dB for all frequency ranges and the unwanted reflection characteristic is -30 dB for frequencies above 1 GHZ. This paper summarizes the remodeling work, and the specifications and performance of the remodeled anechoic chamber.

  11. Ultimate VHF Broadband Interferometer Zen KAWASAKI and Manabu AKITA

    Science.gov (United States)

    Kawasaki, Z.; Akita, M.

    2013-12-01

    Lightning Research Group of Osaka University (LRGOU) has been developing an interferometer for thunderstorm monitoring during these two decades. When LRGOU initiated this project, many related scientists claimed that LRGOU's system was a time of arrival and it must be a sophisticated TOA system. However the key technology of the system were broad band and digital data processing, and it is named the VHF broad band digital interferometer (BDITF), because the phase difference of Fourier components played the very important role. Then the BDITF finally has been realized as a quasi-real time lightning monitoring system, and LRGOU has been operating their BDITFs around Osaka area. Since the BDITF captures the VHF impulses associated with lightning discharges by amplitude triggering, it occasionally misses one of the bi-directional leader progressions because of relatively small amplitude VHF impulses mainly emitted by positive leader tips. All of high density of VHF pulses associated with recoil leaders may not be recorded. Then the ordinary BDITF is able to be accepted as the practical operational system, but from the aspect of science it has been sioriously expected to be improved its performance. To overcome the difficulty New Mexico Institute of Mining and Technology (NMIMT) and LRGOU have started the joint project, and a continuous recording system for digital signals is adopted [M. Stock et al, and M Akita et al,]. The field campaigns have been conducting in New Mexico and in Japan, and successful observations are accomplished. The algorithm to identify individual VHF pulses associated with lightning discharges from back ground noise and/or artificial noise, the dispersion of phase differences for all Fourier components is examined. In case by of small dispersion it is concluded that analyzed VHF pulse has high possibility to be emitted by lightning discharges. This interpretation means that the recorded VHF pulse shape might maintain without deformation during

  12. VHF signal power suppression in stratiform and convective precipitation

    Directory of Open Access Journals (Sweden)

    A. J. McDonald

    2006-03-01

    Full Text Available Previous studies have indicated that VHF clear-air radar return strengths are reduced during periods of precipitation. This study aims to examine whether the type of precipitation, stratiform and convective precipitation types are identified, has any impact on the relationships previously observed and to examine the possible mechanisms which produce this phenomenon. This study uses a combination of UHF and VHF wind-profiler data to define periods associated with stratiform and convective precipitation. This identification is achieved using an algorithm which examines the range squared corrected signal to noise ratio of the UHF returns for a bright band signature for stratiform precipitation. Regions associated with convective rainfall have been defined by identifying regions of enhanced range corrected signal to noise ratio that do not display a bright band structure and that are relatively uniform until a region above the melting layer.

    This study uses a total of 68 days, which incorporated significant periods of surface rainfall, between 31 August 2000 and 28 February 2002 inclusive from Aberystwyth (52.4° N, 4.1° W. Examination suggests that both precipitation types produce similar magnitude reductions in VHF signal power on average. However, the frequency of occurrence of statistically significant reductions in VHF signal power are very different. In the altitude range 2-4 km stratiform precipitation is related to VHF signal suppression approximately 50% of the time while in convective precipitation suppression is observed only 27% of the time. This statistical result suggests that evaporation, which occurs more often in stratiform precipitation, is important in reducing the small-scale irregularities in humidity and thereby the radio refractive index. A detailed case study presented also suggests that evaporation reducing small-scale irregularities in humidity may contribute to the observed VHF signal

  13. VHF signal power suppression in stratiform and convective precipitation

    Directory of Open Access Journals (Sweden)

    A. J. McDonald

    2006-03-01

    Full Text Available Previous studies have indicated that VHF clear-air radar return strengths are reduced during periods of precipitation. This study aims to examine whether the type of precipitation, stratiform and convective precipitation types are identified, has any impact on the relationships previously observed and to examine the possible mechanisms which produce this phenomenon. This study uses a combination of UHF and VHF wind-profiler data to define periods associated with stratiform and convective precipitation. This identification is achieved using an algorithm which examines the range squared corrected signal to noise ratio of the UHF returns for a bright band signature for stratiform precipitation. Regions associated with convective rainfall have been defined by identifying regions of enhanced range corrected signal to noise ratio that do not display a bright band structure and that are relatively uniform until a region above the melting layer. This study uses a total of 68 days, which incorporated significant periods of surface rainfall, between 31 August 2000 and 28 February 2002 inclusive from Aberystwyth (52.4° N, 4.1° W. Examination suggests that both precipitation types produce similar magnitude reductions in VHF signal power on average. However, the frequency of occurrence of statistically significant reductions in VHF signal power are very different. In the altitude range 2-4 km stratiform precipitation is related to VHF signal suppression approximately 50% of the time while in convective precipitation suppression is observed only 27% of the time. This statistical result suggests that evaporation, which occurs more often in stratiform precipitation, is important in reducing the small-scale irregularities in humidity and thereby the radio refractive index. A detailed case study presented also suggests that evaporation reducing small-scale irregularities in humidity may contribute to the observed VHF signal suppression.

  14. VHF volume-imaging radar observation of aspect-sensitive scatterers tilted in mountain waves above a convective boundary layer

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    2005-06-01

    Full Text Available Thin stable atmospheric layers cause VHF radars to receive increased echo power from near zenith. Layers can be tilted from horizontal, for instance by gravity waves, and the direction of VHF "glinting" is measurable by spatial domain interferometry or many-beam Doppler beam swinging (DBS. This paper uses the Middle and Upper atmosphere (MU radar, Shigaraki, Japan as a volume-imaging radar with 64-beam DBS, to show tilting of layers and air flow in mountain waves. Tilt of aspect-sensitive echo power from horizontal is nearly parallel to air flow, as assumed in earlier measurements of mountain-wave alignment. Vertical-wind measurements are self-consistent from different beam zenith angles, despite the combined effects of aspect sensitivity and horizontal-wind gradients.

  15. From VHF to UHF CMOS-MEMS Monolithically Integrated Resonators

    DEFF Research Database (Denmark)

    Teva, Jordi; Berini, Abadal Gabriel; Uranga, A.

    2008-01-01

    This paper presents the design, fabrication and characterization of microresonators exhibiting resonance frequencies in the VHF and UHF bands, fabricated using the available layers of the standard and commercial CMOS technology, AMS-0.35mum. The resonators are released in a post-CMOS process cons...

  16. An HF and lower VHF spectrum assessment system exploiting instantaneously wideband capture

    Science.gov (United States)

    Barnes, Rod I.; Singh, Malkiat; Earl, Fred

    2017-09-01

    We report on a spectral environment evaluation and recording (SEER) system, for instantaneously wideband spectral capture and characterization in the HF and lower VHF band, utilizing a direct digital receiver coupled to a data recorder. The system is designed to contend with a wide variety of electromagnetic environments and to provide accurately calibrated spectral characterization and display from very short (ms) to synoptic scales. The system incorporates a novel RF front end involving automated gain and equalization filter selection which provides an analogue frequency-dependent gain characteristic that mitigates the high dynamic range found across the HF and lower VHF spectrum. The system accurately calibrates its own internal noise and automatically subtracts this from low variance, external spectral estimates, further extending the dynamic range over which robust characterization is possible. Laboratory and field experiments demonstrate that the implementation of these concepts has been effective. Sensitivity to varying antenna load impedance of the internal noise reduction process has been examined. Examples of software algorithms to provide extraction and visualization of spectral behavior over narrowband, wideband, short, and synoptic scales are provided. Application in HF noise spectral density monitoring, spectral signal strength assessment, and electromagnetic interference detection is possible with examples provided. The instantaneously full bandwidth collection provides some innovative applications, and this is demonstrated by the collection of discrete lightning emissions, which form fast ionograms called "flashagrams" in power-delay-frequency plots.

  17. Layered Polar Mesospheric Summer Echoes Observed with the Tri-Static Eiscat VHF

    Science.gov (United States)

    Mann, I.; Anyairo, C.; Häggström, I.; Tjulin, A.

    2014-12-01

    Polar mesospheric summer echoes (PMSE) are strong radar echoes that are typically observed at 50 to 500 MHz. They are often discussed in the context of dusty plasma studies and linked to e.g. the existence of charged ice particles, neutral atmospheric turbulence and atmospheric stratification. The PMSE are observed at mesospheric temperature minimum when ice particles form, though the exact path of formation is still a topic for research. Mesospheric smoke particles that are assumed to form after or during the meteor ablation process possibly contribute to the formation of the ice particles. For understanding the formation of the radar echoes their variation with scattering angle is an important parameter. We analyze PMSE observations with the tri-static EISCAT VHF radar (224 MHz) during one day in June when PMSE were observed almost continuously from 7:00 to 13:00 UT. The radar signal was transmitted and received in zenith direction with the EISCAT VHF antenna near Tromsø. The receivers in Kiruna and Sodankylä were pointed at typical PMSE heights above the Tromsø transmitter and detected radar reflections at the same time and altitude as the Tromsø radar. The altitude of the PMSE changed with time and the extension of the echoes in altitude was smaller toward the end of the observation. These observations are among the first tri-static observations of PMSE. The observations suggest that the scattering process underlying the PMSE occurs over a broad range of scattering angles. Based on the observations we will show that the spectral width of the received echoes is most likely determined by the variations within the observed volume rather than by the scattering process. The observed frequency shifts suggest a layer structure and horizontal motions that vary with altitude. UHF (933 MHz) radar observations were carried out in parallel, they display predominantly incoherent scatter and an electron density typical for the altitude. Some other studies, have in

  18. Phase and coherence analysis of VHF scintillation over Christmas Island

    Directory of Open Access Journals (Sweden)

    E. B. Shume

    2014-03-01

    Full Text Available This short paper presents phase and coherence data from the cross-wavelet transform applied on longitudinally separated very high frequency (VHF equatorial ionospheric scintillation observations over Christmas Island. The phase and coherence analyses were employed on a pair of scintillation observations, namely, the east-looking and west-looking VHF scintillation monitors at Christmas Island. Our analysis includes 3 years of peak season scintillation data from 2008, 2009 (low solar activity, and 2011 (moderate solar activity. In statistically significant and high spectral coherence regions of the cross-wavelet transform, scintillation observations from the east-looking monitor lead those from the west-looking monitor by about 20 to 60 (40 ± 20 min (most frequent lead times. Using several years (seasons and solar cycle of lead (or lag and coherence information of the cross-wavelet transform, we envisage construction of a probability model for forecasting scintillation in the nighttime equatorial ionosphere.

  19. Complementary code and digital filtering for detection of weak VHF radar signals from the mesoscale. [SOUSY-VHF radar, Harz Mountains, Germany

    Science.gov (United States)

    Schmidt, G.; Ruster, R.; Czechowsky, P.

    1983-01-01

    The SOUSY-VHF-Radar operates at a frequency of 53.5 MHz in a valley in the Harz mountains, Germany, 90 km from Hanover. The radar controller, which is programmed by a 16-bit computer holds 1024 program steps in core and controls, via 8 channels, the whole radar system: in particular the master oscillator, the transmitter, the transmit-receive-switch, the receiver, the analog to digital converter, and the hardware adder. The high-sensitivity receiver has a dynamic range of 70 dB and a video bandwidth of 1 MHz. Phase coding schemes are applied, in particular for investigations at mesospheric heights, in order to carry out measurements with the maximum duty cycle and the maximum height resolution. The computer takes the data from the adder to store it in magnetic tape or disc. The radar controller is programmed by the computer using simple FORTRAN IV statements. After the program has been loaded and the computer has started the radar controller, it runs automatically, stopping at the program end. In case of errors or failures occurring during the radar operation, the radar controller is shut off caused either by a safety circuit or by a power failure circuit or by a parity check system.

  20. The first operation and results of the Chung-Li VHF radar

    Science.gov (United States)

    Chao, J. K.; Kuo, F. S.; Chu, Y. S.; Fu, I. J.; Rottger, J.; Liu, C. H.

    1986-01-01

    The Chung-Li Very High Frequency (VHF) radar is used in the dual-mode operations, applying Doppler beam-swinging as well as the spaced-antenna-drift method. The design of the VHF radar is examined. Results of performance tests are discussed.

  1. Occupational Accidents Aboard Merchant Ships

    National Research Council Canada - National Science Library

    H. L. Hansen; D. Nielsen; M. Frydenberg

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational...

  2. Lightning VHF radiation location system based on short-baseline TDOA technique — Validation in rocket-triggered lightning

    Science.gov (United States)

    Sun, Zhuling; Qie, Xiushu; Liu, Mingyuan; Cao, Dongjie; Wang, Dongfang

    2013-07-01

    A lightning VHF radiation location system based on short-baseline time-difference of arrival (TDOA) technology is newly developed. Based on the orthogonal 10 m-baseline antenna array with four identical broadband flat plane antennas, this system receives the lightning broadband VHF radiation signals and calculates TDOA between antennas in order to determine the location of lightning radiation sources in two dimensions (elevation and azimuth). To reduce noise and improve estimation accuracy of time delay, a general correlation time delay estimation algorithm based on direct correlation method and wavelet transform is proposed. Moreover, parabolic interpolation algorithm is used in the fractional delay estimation to improve the time resolution of the positioning system. In this paper, a rocket-triggered lightning discharge and a cloud lightning discharge are analyzed respectively, combining with simultaneous observations of high-speed camera and fast/slow electric field changes. The results indicate that the TDOA location system could effectively map the lightning radiation sources in 2 dimensions and are in a good agreement with the high-speed video camera images.

  3. Range imaging observations of PMSE using the EISCAT VHF radar: Phase calibration and first results

    Directory of Open Access Journals (Sweden)

    J. R. Fernandez

    2005-01-01

    Full Text Available A novel phase calibration technique for use with the multiple-frequency Range IMaging (RIM technique is introduced based on genetic algorithms. The method is used on data collected with the European Incoherent SCATter (EISCAT VHF radar during a 2002 experiment with the goal of characterizing the vertical structure of Polar Mesosphere Summer Echoes (PMSE over northern Norway. For typical Doppler measurements, the initial phases of the transmitter and receiver are not required to be the same. The EISCAT receiver systems exploit this fact, allowing a multi-static configuration. However, the RIM method relies on the small phase differences between closely spaced frequencies. As a result, the high-resolution images produced by the RIM method can be significantly degraded if not properly calibrated. Using an enhanced numerical radar simulator, in which data from multiple sampling volumes are simultaneously generated, the proposed calibration method is validated. Subsequently, the method is applied to preliminary data from the EISCAT radar, providing first results of RIM images of PMSE. Data using conventional analysis techniques, and confirmed by RIM, reveal an often-observed double-layer structure with higher stability in the lower layer. Moreover, vertical velocity oscillations exhibit a clear correlation with the apparent motion of the layers shown in the echo power plots.

  4. Miniaturization for ultrathin metamaterial perfect absorber in the VHF band

    Science.gov (United States)

    Khuyen, Bui Xuan; Tung, Bui Son; Yoo, Young Joon; Kim, Young Ju; Kim, Ki Won; Chen, Liang-Yao; Lam, Vu Dinh; Lee, Youngpak

    2017-03-01

    An efficient resolution for ultrathin metamaterial perfect absorber (MPA) is proposed and demonstrated in the VHF radio band (30-300 MHz). By adjusting the lumped capacitors and the through vertical interconnects, the absorber is miniaturized to be only λ/816 and λ/84 for its thickness and periodicity with respect to the operating wavelength (at 102 MHz), respectively. The detailed simulation and calculation show that the MPA can maintain an absorption rate over 90% in a certain range of incident angle and with a wide variation of capacitance. Additionally, we utilized the advantages of the initial single-band structure to realize a nearly perfect dual-band absorber in the same range. The results were confirmed by both simulation and experiment at oblique incidence angles up to 50°. Our work is expected to contribute to the actualization of future metamaterial-based devices working at radio frequency.

  5. Extraction of forest stand parameters from CARABAS VHF SAR images

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Fredrik [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Centre for Image Analysis

    1999-10-01

    Methods for extracting stand-wise forest parameters from CARABAS VHF SAR images have been developed and evaluated. CARABAS is a unique airborne synthetic aperture radar (SAR), developed by the Swedish Defence Research Establishment. It differs a lot from ordinary microwave radars by using wavelengths between 3.3 and 15 m, making the image intensity highly correlated to stem volume. Furthermore, by providing its own illumination source, the sensor operates independently of daylight and weather conditions. Empirical regression models have been developed for relating backscattering amplitude to stem volume, stem diameter, and tree height. To make comparison between CARABAS image data and forest parameters effective, a fully automatic geo-coding algorithm was developed. Image texture features have also been investigated. By using the variogram as a discriminating feature, CARABAS images and aerial images were segmented into homogeneous regions. Furthermore, a method for discriminating recently clear felled areas from forested areas, combining information from Almaz-1 SAR images and SPOT panchromatic data has also been developed, serving as a comparison to the main work of this thesis. For forest stands at near-horizontal ground, the results for estimating stem volume, stem diameter, and tree height from CARABAS image data are very satisfactory. The root mean square errors for the estimates are comparable to subjective ground-based inventories for dense forest stands. The methods and algorithms described in this thesis have been developed towards an operational remote sensing tool. Altogether, significant potential for mapping of forest characteristics exists using the CARABAS VHF SAR sensor 57 refs, 14 figs, 7 tabs

  6. Occupational accidents aboard merchant ships

    DEFF Research Database (Denmark)

    Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may...... accidents happened on deck. Conclusions: It was possible to clearly identify work situations and specific risk factors for accidents aboard merchant ships. Most accidents happened while performing daily routine duties. Preventive measures should focus on workplace instructions for all important functions...... be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...

  7. Letter to the Editor: Complete maps of the aspect sensitivity of VHF atmospheric radar echoes

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    1999-08-01

    Full Text Available Using the MU radar at Shigaraki, Japan (34.85°N, 136.10°E, we measure the power distribution pattern of VHF radar echoes from the mid-troposphere. The large number of radar beam-pointing directions (320 allows the mapping of echo power from 0° to 40° from zenith, and also the dependence on azimuth, which has not been achieved before at VHF wavelengths. The results show how vertical shear of the horizontal wind is associated with a definite skewing of the VHF echo power distribution, for beam angles as far as 30° or more from zenith, so that aspect sensitivity cannot be assumed negligible at any beam-pointing angle that most existing VHF radars are able to use. Consequently, the use of VHF echo power to calculate intensity of atmospheric turbulence, which assumes only isotropic backscatter at large beam zenith angles, will sometimes not be valid.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; turbulence; instruments and techniques

  8. 78 FR 67309 - Earth Stations Aboard Aircraft

    Science.gov (United States)

    2013-11-12

    ... COMMISSION 47 CFR Part 25 Earth Stations Aboard Aircraft AGENCY: Federal Communications Commission. ACTION... collection associated with the Commission's Earth Station Aboard Aircraft, Report and Order (Order), which adopted licensing and service rules for Earth Stations Aboard Aircraft (ESAA) communicating with Fixed...

  9. PENUMBUHAN LAPISAN TIPIS SILIKON MIKROKRISTAL TERHIDROGENASI DENGAN TEKNIK HWC-VHF-PECVD

    Directory of Open Access Journals (Sweden)

    Ida Usman

    2012-02-01

    Full Text Available Telah dikembangkan teknik HWC-VHF-PECVD (Hot Wire Cell Very High Frequency Plasma Enhanced Chemical Vapor Deposition untuk menumbuhkan lapisan tipis silikon mikrokristal terhidrogenasi (mc-Si:H. Dari hasil penumbuhan lapisan tipis yang dilakukan, teknik HWC-VHF-PECVD memperlihatkan laju deposisi yang lebih tinggi dibandingkan laju deposisi lapisan tipis yang diperoleh dari teknik PECVD maupun teknik VHF-PECVD konvensional. Berdasarkan hasil pengukuran XRD dan SEM, lapisan yang diperoleh pada temperatur filamen yang rendah masih berstruktur amorf. Indikasi yang mengarah pada pembentukan lapisan tipis berstruktur mikrokristalin mulai terlihat pada temperatur filamen ≥ 500oC, dimana puncak-puncak di fraksi spektrum XRD untuk orientasi kristalin tertentu mulai terbentu, sejalan dengan pembentukan butiran-butiran kristalin dari hasil foto SEM permukaan lapisan-lapisan tersebut.

  10. Observations of mesosphere summer echoes with calibrated VHF radars at latitudes between 54°N and 69°N in summer 2004

    Science.gov (United States)

    Latteck, R.; Singer, W.; Kirkwood, S.; Jönsson, L. O.; Eriksson, Håkan

    2005-08-01

    Mesosphere Summer Echoes (MSE) have been observed with 50-MHz VHF radars at middle (MSE) and polar latitudes (PMSE) for more than 20 years. The occurrence and seasonal variation of these radar echoes as well as their dependence on solar and geomagnetic activity are mostly studied basing on relative signal strength measurements (signal-to-noise ratios). The latitudinal dependence of the appearance and intensity of mesospheric summer echoes is still an open question as the widely used relative signal strength observations are determined by the atmospheric properties as well as by the individual radar characteristics. The use of absolutely calibrated echo powers allows a system in-depended comparison of mesospheric summer echoes observed at different sites by different systems. We present two different radar calibration methods. One applies a noise source to calibrate the receive path of the radar only, a second uses the radar signal itself to calibrate the complete transmitting and receiving path of the radar system. Both techniques and the same calibration hardware have been applied to the ALWIN VHF radar at Andenes/Norway (69°N), the ESRAD radar at Kiruna/Sweden (68deg;N) and OSWIN radar at Kühlungsborn/Germany (54°N). The sensitivity of the different radar systems and the seasonal and diurnal variation of the occurrence of mesospheric summer echoes at different locations are discussed on the basis of radar backscatter cross-sections.

  11. A VHF Class E DC-DC Converter with Self-Oscillating Gate Driver

    DEFF Research Database (Denmark)

    Andersen, Toke Meyer; Christensen, Søren K.; Knott, Arnold

    2011-01-01

    This paper describes the analysis and design of a DC-DC converter topology which is operational at frequencies in the Very High Frequency (VHF) band ranging from 30 MHz − 300 MHz. The presented topology, which consists of a class E inverter, class E rectifier, and self-oscillating gate driver, is...

  12. VHF SoOp (Signal of Opportunity) Technology Demonstration for Soil Moisture Measurement Using Microwave Hydraulic Boom Truck Platform

    Science.gov (United States)

    Joseph, Alicia; Deshpande, Manohar; O'Neill, Peggy; Miles, Lynn

    2017-04-01

    A goal of this research is to test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a global direct surface soil moisture (SM) and RZSM measurement system over a variety of land covers. Knowledge of RZSM up to a depth of 1 meter and surface SM up to a depth of 0.05 meter on a global scale, at a spatial resolution of 1-10 km through moderate-to-heavy vegetation, is critical to understanding global water resources and the vertical moisture gradient in the Earth's surface layer which controls moisture interactions between the soil, vegetation, and atmosphere. Current observations of surface SM from space by L-band radiometers (1.4 GHz) and radars (1.26 GHz) are limited to measurements of surface SM up to a depth of 0.05 meter through moderate amounts of vegetation. This limitation is mainly due to the inability of L-band signals to penetrate through dense vegetation and deep into the soil column. Satellite observations of the surface moisture conditions are coupled to sophisticated models which extrapolate the surface SM into the root zone, thus providing an indirect estimate rather than a direct measurement of RZSM. To overcome this limitation, low-frequency airborne radars operating at 435 MHz and 118 MHz have been investigated, since these lower frequencies should penetrate denser vegetation and respond to conditions deeper in the soil. This presentation describes a new and less expensive technique for SM as well as RZSM direct measurement using Signal of Opportunity transmitters. Being less expensive and needing only passive simple RF receiver, the SoOp concept has the potential for being used for space borne applications, thus providing global SM and RZSM measurements. This study will describe

  13. Testing VHF/GPS collar design and safety in the study of free-roaming horses.

    Directory of Open Access Journals (Sweden)

    Gail H Collins

    Full Text Available Effective and safe monitoring techniques are needed by U.S. land managers to understand free-roaming horse behavior and habitat use and to aid in making informed management decisions. Global positioning system (GPS and very high frequency (VHF radio collars can be used to provide high spatial and temporal resolution information for detecting free-roaming horse movement. GPS and VHF collars are a common tool used in wildlife management, but have rarely been used for free-roaming horse research and monitoring in the United States. The purpose of this study was to evaluate the design, safety, and detachment device on GPS/VHF collars used to collect free-roaming horse location and movement data. Between 2009 and 2010, 28 domestic and feral horses were marked with commercial and custom designed VHF/GPS collars. Individual horses were evaluated for damage caused by the collar placement, and following initial observations, collar design was modified to reduce the potential for injury. After collar modifications, which included the addition of collar length adjustments to both sides of the collar allowing for better alignment of collar and neck shapes, adding foam padding to the custom collars to replicate the commercial collar foam padding, and repositioning the detachment device to reduce wear along the jowl, we observed little to no evidence of collar wear on horses. Neither custom-built nor commercial collars caused injury to study horses, however, most of the custom-built collars failed to collect data. During the evaluation of collar detachment devices, we had an 89% success rate of collar devices detaching correctly. This study showed that free-roaming horses can be safely marked with GPS and/or VHF collars with minimal risk of injury, and that these collars can be a useful tool for monitoring horses without creating a risk to horse health and wellness.

  14. Molecular Switching in Confined Spaces: Effects of Encapsulating the DHA/VHF Photo-Switch in Cucurbiturils

    DEFF Research Database (Denmark)

    Petersen, Michael Å.; Rasmussen, Brian; Andersen, Nicolaj N.

    2017-01-01

    complexes, the kinetics of the thermal VHF-to-DHA back-reaction is accelerated, while in CB8 inclusion complexes, the kinetics is slowed down as compared to the free photo-switch. The effect of the CB encapsulation of the photo-switch can be effectively canceled by introducing a guest that binds the CB more...... strongly. According to DFT calculations, a stabilization of the reactive s-cis VHF conformer relative to the s-trans VHF appears to be a contributing factor responsible for the accelerated back-reaction when encapsulated in CB7....

  15. Development of a Coherent Bistatic Vegetation Model for Signal of Opportunity Applications at VHF UHF-Bands

    Science.gov (United States)

    Kurum, Mehmet; Deshpande, Manohar; Joseph, Alicia T.; O'Neill, Peggy E.; Lang, Roger H.; Eroglu, Orhan

    2017-01-01

    A coherent bistatic vegetation scattering model, based on a Monte Carlo simulation, is being developed to simulate polarimetric bi-static reflectometry at VHF/UHF-bands (240-270 MHz). The model is aimed to assess the value of geostationary satellite signals of opportunity to enable estimation of the Earth's biomass and root-zone soil moisture. An expression for bistatic scattering from a vegetation canopy is derived for the practical case of a ground-based/low altitude platforms with passive receivers overlooking vegetation. Using analytical wave theory in conjunction with distorted Born approximation (DBA), the transmit and receive antennas effects (i.e., polarization, orientation, height, etc.) are explicitly accounted for. Both the coherency nature of the model (joint phase and amplitude information) and the explicit account of system parameters (antenna, altitude, polarization, etc) enable one to perform various beamforming techniques to evaluate realistic deployment configurations. In this paper, several test scenarios will be presented and the results will be evaluated for feasibility for future biomass and root-zone soil moisture application using geostationary communication satellite signals of opportunity at low frequencies.

  16. A system for mapping sources of VHF and electric field pulses from in-cloud lightning at KSC

    Science.gov (United States)

    Thomson, Ewen M.; Medelius, Pedro J.

    1991-01-01

    The literature concerning VHF radiation and wideband electric fields from in-cloud lightning is reviewed. VHF location systems give impressive radio images of lightning in clouds with high spatial and temporal resolution. Using systems based on long and short baseline time-or-arrival and interferometry, workers have detected VHF sources that move at speeds of 10(exp 5) to 10(exp 8) m/s. The more slowly moving sources appear to be associated with channel formation but the physical basis for the higher speeds is not clear. In contrast, wideband electric fields are directly related to physical parameters such as current and tortuosity. A long baseline system is described to measure simultaneously VHF radiation and wideband electric fields at five stations at Kennedy Space Center. All signals are detected over remote, isolated ground planes with fiber optics for data transmission. The modification of this system to map rapidly varying dE/dt pulses is discussed.

  17. Investigation into the Effects of VHF and UHF Band Radiation on Hewlett-Packard (HP) Cesium Beam Frequency Standards

    National Research Council Canada - National Science Library

    Dickens, Andrew

    1994-01-01

    This paper documents an investigation into reports which have indicated that exposure to VHF and UHF band radiation has adverse effects on the frequency stability of HP cesium beam frequency standards...

  18. Investigation into the effects of VHF and UHF band radiation on Hewlett-Packard (HP) Cesium Beam Frequency Standards

    Science.gov (United States)

    Dickens, Andrew

    1995-01-01

    This paper documents an investigation into reports which have indicated that exposure to VHF and UHF band radiation has adverse effects on the frequency stability of HP cesium beam frequency standards. Tests carried out on the basis of these reports show that sources of VHF and UHF radiation such as two-way hand held police communications devices do cause reproducible adverse effects. This investigation examines reproducible effects and explores possible causes.

  19. Comparison study of Lightning VHF interferometric and LF time-of-arival maps

    Science.gov (United States)

    Kudo, A.; Stock, M.; Kawasaki, Z.; Ushio, T.

    2016-12-01

    Lightning discharges radiate broad band frequency electromagnetic waves from ULF to UHF. Using sensors which detect this radiation is an effective technique to detect lightning flashes, even if they are in a cloud. If multiple sensors are present, a lightning flash can be located using various techniques. At low frequencies, the power radiated by lightning is very high, but because the wavelengths are long, the location resolution is somewhat low. At very high frequencies, the wavelengths are much shorter allowing for much better location resolution, but the power radiation is also much lower, making it more difficult to detect. The VHF band is a good compromise between good location resolution, and good detection efficiency. One technique to locate VHF signals from lightning is interferometry. Using this technique, the signals arriving at three or more VHF broadband antennas are coherently combined to produce an image of the lightning flash. The current generation broadband lightning interferometer being developed in Japan by RAIRAN and the University of Osaka called Lightning Interferometer via VHF Emission (LIVE). Currently, LIVE is installed in Kaizuka, a city to the south of Osaka, near Osaka Bay to observe Japanese summer lightning. In the current study, we are comparing the high detail, 2-dimensional lightning maps produced by LIVE to the lower detail, 3-dimensional maps produced by a low frequency time-of-arrival system called the Broadband Observation network for Lightning and Thunderstorms (BOLT). In order to better compare the data, a new GPS timing device is being developed for LIVE to allow high absolute timing accuracy without sacrificing one of the 4 high speed digitizer channels. The objectives of the study are to better understand Japanese summer lightning, and to prepare for a future campaign as part of the GLM validation study.

  20. Bias-Voltage Stabilizer for HVHF Amplifiers in VHF Pulse-Echo Measurement Systems

    Directory of Open Access Journals (Sweden)

    Hojong Choi

    2017-10-01

    Full Text Available The impact of high-voltage–high-frequency (HVHF amplifiers on echo-signal quality is greater with very-high-frequency (VHF, ≥100 MHz ultrasound transducers than with low-frequency (LF, ≤15 MHz ultrasound transducers. Hence, the bias voltage of an HVHF amplifier must be stabilized to ensure stable echo-signal amplitudes. We propose a bias-voltage stabilizer circuit to maintain stable DC voltages over a wide input range, thus reducing the harmonic-distortion components of the echo signals in VHF pulse-echo measurement systems. To confirm the feasibility of the bias-voltage stabilizer, we measured and compared the deviations in the gain of the HVHF amplifier with and without a bias-voltage stabilizer. Between −13 and 26 dBm, the measured gain deviations of a HVHF amplifier with a bias-voltage stabilizer are less than that of an amplifier without a bias-voltage stabilizer. In order to confirm the feasibility of the bias-voltage stabilizer, we compared the pulse-echo responses of the amplifiers, which are typically used for the evaluation of transducers or electronic components used in pulse-echo measurement systems. From the responses, we observed that the amplitudes of the echo signals of a VHF transducer triggered by the HVHF amplifier with a bias-voltage stabilizer were higher than those of the transducer triggered by the HVHF amplifier alone. The second, third, and fourth harmonic-distortion components of the HVHF amplifier with the bias-voltage stabilizer were also lower than those of the HVHF amplifier alone. Hence, the proposed scheme is a promising method for stabilizing the bias voltage of an HVHF amplifier, and improving the echo-signal quality of VHF transducers.

  1. First wind shear observation in PMSE with the tristatic EISCAT VHF radar

    OpenAIRE

    Mann, Ingrid; Häggström, I.; Tjulin, A; Rostami, S; Anyairo, CC; Dalin, P

    2016-01-01

    (c) American Geophysical Union, reprinted with permission. Article also available at source: https://doi.org/10.1002/2016JA023080 The Polar Summer Mesosphere has the lowest temperatures that occur in the entire Earth system. Water ice particles below the optically observable size range participate there in the formation of strong radar echoes (Polar Mesospheric Summer Echoes, PMSE). To study PMSE we carried out observations with the European Incoherent Scatter (EISCAT) VHF and EIS...

  2. Bias-Voltage Stabilizer for HVHF Amplifiers in VHF Pulse-Echo Measurement Systems.

    Science.gov (United States)

    Choi, Hojong; Park, Chulwoo; Kim, Jungsuk; Jung, Hayong

    2017-10-23

    The impact of high-voltage-high-frequency (HVHF) amplifiers on echo-signal quality is greater with very-high-frequency (VHF, ≥100 MHz) ultrasound transducers than with low-frequency (LF, ≤15 MHz) ultrasound transducers. Hence, the bias voltage of an HVHF amplifier must be stabilized to ensure stable echo-signal amplitudes. We propose a bias-voltage stabilizer circuit to maintain stable DC voltages over a wide input range, thus reducing the harmonic-distortion components of the echo signals in VHF pulse-echo measurement systems. To confirm the feasibility of the bias-voltage stabilizer, we measured and compared the deviations in the gain of the HVHF amplifier with and without a bias-voltage stabilizer. Between -13 and 26 dBm, the measured gain deviations of a HVHF amplifier with a bias-voltage stabilizer are less than that of an amplifier without a bias-voltage stabilizer. In order to confirm the feasibility of the bias-voltage stabilizer, we compared the pulse-echo responses of the amplifiers, which are typically used for the evaluation of transducers or electronic components used in pulse-echo measurement systems. From the responses, we observed that the amplitudes of the echo signals of a VHF transducer triggered by the HVHF amplifier with a bias-voltage stabilizer were higher than those of the transducer triggered by the HVHF amplifier alone. The second, third, and fourth harmonic-distortion components of the HVHF amplifier with the bias-voltage stabilizer were also lower than those of the HVHF amplifier alone. Hence, the proposed scheme is a promising method for stabilizing the bias voltage of an HVHF amplifier, and improving the echo-signal quality of VHF transducers.

  3. 2-D inner-shelf current observations from a single VHF WEllen RAdar (WERA) station

    Science.gov (United States)

    Voulgaris, G.; Kumar, N.; Gurgel, K.-W.; Warner, J.C.; List, J.H.

    2011-01-01

    The majority of High Frequency (HF) radars used worldwide operate at medium to high frequencies (8 to 30 MHz) providing spatial resolutions ranging from 3 to 1.5 km and ranges from 150 to 50 km. This paper presents results from the deployment of a single Very High Frequency (VHF, 48 MHz) WEllen RAdar (WERA) radar with spatial resolution of 150 m and range 10-15 km, used in the nearshore off Cape Hatteras, NC, USA. It consisted of a linear array of 12 antennas operating in beam forming mode. Radial velocities were estimated from radar backscatter for a variety of wind and nearshore wave conditions. A methodology similar to that used for converting acoustically derived beam velocities to an orthogonal system is presented for obtaining 2-D current fields from a single station. The accuracy of the VHF radar-derived radial velocities is examined using a new statistical technique that evaluates the system over the range of measured velocities. The VHF radar velocities showed a bias of 3 to 7 cm/s over the experimental period explainable by the differences in radar penetration and in-situ measurement height. The 2-D current field shows good agreement with the in-situ measurements. Deviations and inaccuracies are well explained by the geometric dilution analysis. ?? 2011 IEEE.

  4. Structure, optical properties and thermal stability of HfErO films deposited by simultaneous RF and VHF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H.Y. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Nanjing University of Posts and Telecommunications, School of Tongda, Nanjing (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); He, H.J.; Zhang, Z.; Jin, C.G.; Yang, Y.; Wang, Y.Y.; Ye, C. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Zhuge, L.J. [Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Soochow University, Analysis and Testing Center, Suzhou (China); Wu, X.M. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Chinese Academy of Sciences, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Shanghai (China)

    2015-01-23

    HfErO films are deposited on Si substrates by simultaneous radio frequency (RF) and very high frequency (VHF) magnetron sputtering technique. The content of the doped ingredient of Er and the body composition of HfO{sub x} are, respectively, controlled through the VHF and RF powers. Low content of Er doping in the HfErO films can be achieved, because the VHF source of 27.12 MHz has higher ion energy and lower ion flux than the RF source resulting in low sputtering rate in the magnetron sputtering system. The structure, optical properties and thermal stability of the HfErO films are investigated in this work. Results show that the doped content of Er is independently controlled by the VHF power. The oxygen vacancies are created by the Er incorporation. The hafnium in the HfErO films forms mixed valence of Hf{sup 2+} and Hf{sup 4+}. The HfErO films are composed with the structures of HfO{sub 2}, HfO and ErO{sub x}, which can be optimized through the VHF power. At high VHF power, the Hf-Er-O bonds are formed, which demonstrates that the Er atoms are doped into the lattice of HfO{sub 2} in the HfErO films. The HfErO films have bad thermal stability as the crystallization temperature decreases from 900 to 800 C. After thermal annealing, cubic phase of HfO{sub 2} are stabilized, which is ascribed to the oxygen vacancies creation by the Er incorporation. The optical properties such as the refractive index and the optical band gap of the HfErO films are optimized by the VHF power. (orig.)

  5. High-resolution observation of field-aligned irregularities in the ionosphere using multi-frequency range imaging of VHF atmospheric radar

    Science.gov (United States)

    Chen, Jenn-Shyong; Furumoto, Jun-ichi; Su, Ching-Lun; Chu, Yen-Hsyang

    Field-aligned irregularity (FAI) in the ionosphere is a topic of interest to atmospheric radar community. In addition to the field-aligned characteristic, quasi-periodic (QP) appearance of FAI echoes has been observed frequently by very-high-frequency (VHF) atmospheric radar. The occurrence range of QP FAI echoes changes with time, and the slope of range versus time can be positive or negative, depending on occurrence time of the echoes. Several mechanisms responsible for the QP FAI echoes have been proposed, e.g., modulation in altitude by a passing atmospheric gravity wave, semidiurnal neutral-wind variation, and so on. Owing to the finite pulse length of radar in observation, the range resolution of measurement is limited within hundreds of meters. In view of this, the range imaging (RIM) using multiple frequencies has been employed to improve the range resolution of measurement. The multi-frequency technique transmits a set of slightly different frequencies sequentially during each radar pulse, and the radar returns at different transmitting frequencies are received, respectively. With adaptive retrieval algorithms for these radar returns, it is capable of resolving the echo structures at meter scale in the range direction. RIM has been employed in the lower atmosphere successfully. In this study, the performance of RIM for FAI was first carried out with the Middle and Upper atmosphere Radar (46 MHz; 34.85(°) N, 136.10(°) N; Japan) and the Chung-Li VHF radar (52 MHz; 24.9(°) N, 121.1(°) E; Taiwan). Some initial results of high-resolution FAI echoes within the range gate will be shown.

  6. Forming and detection of digital watermarks in the System for Automatic Identification of VHF Transmissions

    Directory of Open Access Journals (Sweden)

    О. В. Шишкін

    2013-07-01

    Full Text Available Forming and detection algorithms for digital watermarks are designed for automatic identification of VHF radiotelephone transmissions in the maritime and aeronautical mobile services. An audible insensitivity and interference resistance of embedded digital data are provided by means of OFDM technology jointly with normalized distortions distribution and data packet detection by the hash-function. Experiments were carried out on the base of ship’s radio station RT-2048 Sailor and USB ADC-DAC module of type Е14-140M L-CARD in the off-line processing regime in Matlab medium

  7. Luminous phenomena and electromagnetic VHF wave emission originated from earthquake-related radon exhalation

    Science.gov (United States)

    Seki, A.; Tobo, I.; Omori, Y.; Muto, J.; Nagahama, H.

    2013-12-01

    Anomalous luminous phenomena and electromagnetic wave emission before or during earthquakes have been reported (e.g., the 1965 Matsushiro earthquake swarm). However, their mechanism is still unsolved, in spite of many models for these phenomena. Here, we propose a new model about luminous phenomena and electromagnetic wave emission during earthquake by focusing on atmospheric radon (Rn-222) and its daughter nuclides (Po-218 and Po-214). Rn-222, Po-218 and Po-214 are alpha emitters, and these alpha particles ionize atmospheric molecules. A light emission phenomenon, called 'the air luminescence', is caused by de-excitation of the ionized molecules of atmospheric nitrogen due to electron impact ionization from alpha particles. The de-excitation is from the second positive system of neutral nitrogen molecules and the first negative system of nitrogen molecule ion. Wavelengths of lights by these transitions include the visible light wavelength. So based on this mechanism, we proposed a new luminous phenomenon model before or during earthquake: 1. The concentration of atmospheric radon and its daughter nuclides increase anomalously before or during earthquakes, 2. Nitrogen molecules and their ions are excited by alpha particles emitted from Rn-222, Po-218 and Po-214, and air luminescence is generated by their de-excitation. Similarly, electromagnetic VHF wave emission can be explained by ionizing effect of radon and its daughter nuclides. Boyarchuk et al. (2005) proposed a model that electromagnetic VHF wave emission is originated when excited state of neutral clusters changes. Radon gas ionizes atmosphere and forms positively and negatively charged heavy particles. The process of ion hydration in ordinary air can be determined by the formation of complex chemically active structures of the various types of ion radicals. As a result of the association of such hydration radical ions, a neutral cluster, which is dipole quasi-molecules, is formed. A neutral cluster

  8. Observations of Mesospheric Turbulence by Rocket Probe and VHF Radar, Part 2.4A

    Science.gov (United States)

    Royrvik, O.; Smith, L. G.

    1984-01-01

    Data from the Jicamarca VHF radar and from a Languir probe fine-structure on a Nike Orion rocket launched from Punto Lobos, Peru, have been compared. A single mesospheric scattering layer was observed by the radar. The Langmuir probe detected irregularities in the electron-density profile in a narrow region between 85.2 and 86.6 km. It appears from a comparison between these two data sets that turbulence in the neutral atmosphere is the mechanism generating the refractive index irregularities.

  9. VHF radar observation of atmospheric winds, associated shears and C2n at a tropical location: interdependence and seasonal pattern

    Directory of Open Access Journals (Sweden)

    A. R. Jain

    Full Text Available The turbulence refractivity structure constant (C2n is an important parameter of the atmosphere. VHF radars have been used extensively for the measurements of C2n. Presently, most of such observations are from mid and high latitudes and only very limited observations are available for equatorial and tropical latitudes. Indian MST radar is an excellent tool for making high-resolution measurements of atmospheric winds, associated shears and turbulence refractivity structure constant (C2n. This radar is located at Gadanki (13.45° N, 79.18° E, a tropical station in India. The objective of this paper is to bring out the height structure of C2n for different seasons using the long series of data (September 1995 – August 1999 from Indian MST radar. An attempt is also made to understand such changes in the height structure of C2n in relation to background atmospheric parameters such as horizontal winds and associated shears. The height structure of C2n, during the summer monsoon and post-monsoon season, shows specific height features that are found to be related to Tropical Easterly Jet (TEJ winds. It is important to examine the nature of the radar back-scatterers and also to understand the causative mechanism of such scatterers. Aspect sensitivity of the received radar echo is examined for this purpose. It is observed that radar back-scatterers at the upper tropospheric and lower stratospheric heights are more anisotropic, with horizontal correlation length of 10–20 m, as compared to those observed at lower and middle tropospheric heights.Key words. Meteorology and atmospheric dynamics (climatology; tropical meteorology; turbulence

  10. Books Received

    Indian Academy of Sciences (India)

    VG Bhide. Shekhar Phatak and Associates. 1998, Rs.80. Books Received. Biotechnological Methods of. Pollution Control. S A Abbasi and E Ramasami. Universities Press. 1999, Rs.1S0. The Penguin India Career Guide,. Vol 2, The Scien~es. Usha Albuquerque. Penguin Books. 1996, Rs.250. Fixed Points. Yu A Shashldn.

  11. Books Received

    Directory of Open Access Journals (Sweden)

    Murat Akser

    2014-10-01

    Full Text Available In 2014 we have received a variety of books onc inema and media from these publishers: Bloomsbury Academic, Cambridge Scholars Publishing, Continuum, Edinburgh University Press, Focal Press, Intellect, Paradigm, Peter Lang, Routledge, University of California Press, Wayne State University Press.

  12. Books Received

    Indian Academy of Sciences (India)

    Books Received. Challenge and Thrill of Pre-College. Mathematics. V Krishnamurthy et al. New Age International. 1996, Rs.220. Mathematics for Science. S M Uppal and H M Humphreys. New Age International. 1996, Rs.17S. Physics for Engineers. M R Srinivasan. New Age Publications. 1996. Statement about ownership ...

  13. Measurements and simulation of ionospheric scattering on VHF and UHF radar signals: Channel scattering function

    Science.gov (United States)

    Rogers, Neil C.; Cannon, Paul S.; Groves, Keith M.

    2009-02-01

    The design and operation of transionospheric VHF and UHF radars requires knowledge of amplitude and phase scintillation due to ionospheric scattering. Phase coherence is of particular importance where long coherent integration periods and large bandwidths are required. A thin phase screen, parabolic equation based, Trans-Ionospheric Radio Propagation Simulator (TIRPS) is described. Modeled channel scattering functions (CSFs) are compared to experimental VHF and UHF data derived from the Advanced Research Projects Agency Long-range Tracking and Instrumentation Radar on Kwajalein Island (9.4°N, 166.8°E). TIRPS quantitatively reproduces the experimental results, including the quasi-parabolic profile observed in the measured CSFs under strong turbulence conditions. Variations in the simulated CSF with ionospheric phase screen parameters are also presented. Under conditions of high integrated strength of turbulence (CkL), a low phase spectral index (p = 1), indicating relatively dense small-scale irregularities, produces pronounced range spreading. Conversely, when the spectral index is high (p = 4), indicative of strong focusing/defocusing by large-scale irregularities, there is increased Doppler spreading and, when the outer scale of irregularities is large, a greater likelihood of asymmetry of the CSF about the zero Doppler axis.

  14. PMSE strength during enhanced D region electron densities: Faraday rotation and absorption effects at VHF frequencies

    Science.gov (United States)

    Chau, Jorge L.; Röttger, Jürgen; Rapp, Markus

    2014-10-01

    In this paper we study the effects of absorption and Faraday rotation on measurements of polar mesosphere summer echoes (PMSE). We found that such effects can produce significant reduction of signal-to-noise ratio (SNR) when the D region electron densities (Ne) are enhanced, and VHF radar systems with linearly polarized antennas are used. In particular we study the expected effects during the strong solar proton event (SPE) of July 2000, also known as the Bastille day flare event. During this event, a strong anti-correlation between the PMSE SNR and the D-region Ne was found over three VHF radar sites at high latitudes: Andøya, Kiruna, and Svalbard. This anti-correlation has been explained (a) in terms of transport effects due to strong electric fields associated to the SPE and (b) due to a limited amount of aerosol particles as compared to the amount of D-region electrons. Our calculations using the Ne profiles used by previous researchers explain most, if not all, of the observed SNR reduction in both time (around the SPE peak) and altitude. This systematic effect, particularly the Faraday rotation, should be recognized and tested, and possibly avoided (e.g., using circular polarization), in future observations during the incoming solar maximum period, to contribute to the understanding of PMSE during enhanced D region Ne.

  15. VHF/UHF radar observations of tropical mesoscale convective systems over southern India

    Directory of Open Access Journals (Sweden)

    K. Kishore Kumar

    2005-07-01

    Full Text Available Several campaigns have been carried out to study the convective systems over Gadanki (13.5° N, 79.2° E, a tropical station in India, using VHF and UHF radars. The height-time sections of several convective systems are investigated in detail to study reflectivity, turbulence and vertical velocity structure. Structure and dynamics of the convective systems are the main objectives of these campaigns. The observed systems are classified into single- and multi-cell systems. It has been observed that most of the convective systems at this latitude are multi-cellular in nature. Simultaneous VHF and UHF radar observations are used to classify the observed precipitating systems as convective, intermediary and stratiform regions. Composite height profiles of vertical velocities in these regions were obtained and the same were compared with the profiles obtained at other geographical locations. These composite profiles of vertical velocity in the convective regions have shown their peaks in the mid troposphere, indicating that the maximum latent heat is being released at those heights. These profiles are very important for numerical simulations of the convective systems, which vary significantly from one geographical location to the other. Keywords. Meteorology and atmospheric dynamics (Mesoscale meteorology; Convective processes – Radio science (Remote sensing

  16. Anchorage Receives Record Snowfall

    Science.gov (United States)

    2002-01-01

    The forecast called for flurries, but the snow accumulated on the ground in Anchorage, Alaska, at the rate of 2 inches per hour (5 cm per hour) for much of Saturday, March 16, 2002. By the time the winter storm passed on Sunday afternoon, Anchorage had received 28.6 inches (72.6 cm) of snow, surpassing by far the previous record of 15.6 inches (39.6 cm) set on December 29, 1955. Flights were canceled and schools were closed as a result of the storm. This true-color image of Alaska was acquired by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, on March 18. It appears another large, low-pressure system is heading toward the Anchorage region, which could bring substantially more snowfall. The low-pressure system can be identified by the characteristic spiral pattern of clouds located off Alaska's southwestern coast in this scene.

  17. Molecular Switching in Confined Spaces: Effects of Encapsulating the DHA/VHF Photo-Switch in Cucurbiturils.

    Science.gov (United States)

    Petersen, Michael Å; Rasmussen, Brian; Andersen, Nicolaj N; Sauer, Stephan P A; Nielsen, Mogens Brøndsted; Beeren, Sophie R; Pittelkow, Michael

    2017-09-18

    Confinement of reactive chemical species uniquely affects chemical reactivity by restricting the physical space available and by restricting access to interactions with the solvent. In Nature, for example, confined protein binding pockets govern processes following photoisomerization reactions and the isomerizations themselves. Here we describe the first example of a dihydroazulene/vinylheptafulvene (DHA/VHF) photo-switch functioning in water, and we show how its switching behavior is strongly influenced by supramolecular interactions with a series of cucurbit[n]uril (CB) host molecules. In CB7 inclusion complexes, the kinetics of the thermal VHF-to-DHA back-reaction is accelerated, while in CB8 inclusion complexes, the kinetics is slowed down as compared to the free photo-switch. The effect of the CB encapsulation of the photo-switch can be effectively canceled by introducing a guest that binds the CB more strongly. According to DFT calculations, a stabilization of the reactive s-cis VHF conformer relative to the s-trans VHF appears to be a contributing factor responsible for the accelerated back-reaction when encapsulated in CB7. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Frequency Reuse, Cell Separation, and Capacity Analysis of VHF Digital Link Mode 3 TDMA

    Science.gov (United States)

    Shamma, Mohammed A.; Nguyen, Thanh C.; Apaza, Rafael D.

    2003-01-01

    The most recent studies by the Federal Aviation Administration (FAA) and the aviation industry have indicated that it has become increasingly difficult to make new VHF frequency or channel assignments to meet the aviation needs for air-ground communications. FAA has planned for several aggressive improvement measures to the existing systems, but these measures would not meet the projected voice communications needs beyond 2009. FAA found that since 1974 there has been, on the average, a 4 percent annual increase in the number of channel assignments needed to satisfy the air-ground communication traffic (approximately 300 new channel assignments per year). With the planned improvement measures, the channel assignments are expected to reach a maximum number of 16615 channels by about 2010. Hence, the FAA proposed the use of VDL Mode 3 as a new integrated digital voice and data communications systems to meet the future air traffic demand. This paper presents analytical results of frequency reuse; cell separation and capacity estimation of VDL Mode 3 TDMA systems that FAA has planned to implement the future VHF air-ground communications system by the year 2010. For TDMA, it is well understood that the frequency reuse factor is a crucial parameter for capacity estimation. Formulation of this frequency reuse factor is shown, taking into account the limitation imposed by the requirement to have a sufficient Signal to Co-Channel Interference Ratio. Several different values for the Signal to Co-Channel Interference Ratio were utilized corresponding to the current analog VHF DSB-AM systems, and the future digital VDL Mode 3. The required separation of Co-Channel cells is computed for most of the Frequency Protected Service Volumes (FPSV's) currently in use by the FAA. Additionally, the ideal cell capacity for each FPSV is presented. Also, using actual traffic for the Detroit air space, a FPSV traffic distribution model is used to generate a typical cell for channel capacity

  19. Disturbance-induced responses of VHF and satellite tagged harbour seals

    DEFF Research Database (Denmark)

    Andersen, Signe May; Teilmann, Jonas; Dietz, Rune

    2014-01-01

    ABSTRACT 1. The response of individual harbour seals (Phoca vitulina) to controlled and sporadic disturbances when hauled out in the Anholt seal reserve, Denmark, was studied. Sporadic disturbances from pedestrians, boats, low-flying aeroplanes and grey seals (Halichoerus grypus) were observed...... in or near the reserve. VHF and satellite transmitters were attached to eight harbour seals to determine post-disturbance and undisturbed behaviour during the pre-breeding period (25 April to 21 May 2008). 2. Both disturbed and undisturbed seals mostly returned to the haul-out site from dusk and throughout...... within 40 km from the haul-out site. The maximum extent of post-disturbance trips, however, varied among individuals and disturbance types, and was strongly correlated with the duration of trips. 3. Disturbed and undisturbed seals used the same areas, suggesting that these areas represent normal foraging...

  20. Graphene-based tunable non-foster circuit for VHF applications

    Directory of Open Access Journals (Sweden)

    Jing Tian

    2016-06-01

    Full Text Available This paper presents a negative impedance converter (NIC based on graphene field effect transistors (GFETs for VHF applications. The NIC is designed following Linvill’s open circuit stable (OCS topology. The DC modelling parameters of GFET are extracted from a device measured by Meric et al. [IEEE Electron Devices Meeting, 23.2.1 (2010] Estimated parasitics are also taken into account. Simulation results from Keysight Advanced Design System (ADS show good NIC performance up to 200 MHz and the value of negative capacitance is directly proportional to the capacitive load. In addition, it has been shown that by varying the supply voltage the value of negative capacitance can also be tuned. The NIC stability has been tested up to 2 GHz (10 times the maximum operation frequency using Nyquist stability criterion to ensure there are no oscillation issues.

  1. Final environmental assessment for vegetation control at VHF stations, microwave stations, electrical substations, and pole yards

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-13

    Southwestern Power Adm. operates very high frequency (VHF) and microwave radio stations, electrical substations, and pole yards for electric power transmission throughout AR, MO, and OK. Vegetation growth at the stations must be suppressed for safety of operation and personnel. Southwestern has been using a combination of mechanical/manual and herbicide control for this purpose; Federally- mandated reductions in staff and budgetary resources require Southwestern to evaluate all potentially efficient methods for vegetation control. Three alternatives were examined: no action, mechanical/manual control, and (proposed) a combination of mechanical/manual and herbicide control. Environmental impacts on air and water quality, wetlands, wildlife, endangered species, archaeological and other resources, farmland, human health, transportation, etc. were evaluated.

  2. Simultaneous observation of sporadic E with a rapid-run ionosonde and VHF coherent backscatter radar

    Directory of Open Access Journals (Sweden)

    T. Maruyama

    2006-03-01

    Full Text Available During the SEEK 2 rocket campaign, ionograms were recorded every minute at the Yamagawa Radio Observatory at about 90km west of the region monitored by a VHF (very high frequency coherent backscatter radar. Sporadic E-layer parameters, which include the critical (foEs and blanketing (fbEs frequencies, the layer height (h'Es, and the width of the range spread of sporadic E-traces, were compared with RTI (range-time-intensity plots of VHF quasi-periodic (QP and continuous coherent backscatter echoes. A close relationship was found between the appearance of QP echoes in the RTI plots and the level of spatial inhomogeneity in sporadic E plasma, signified here by the difference between foEs and fbEs. During QP echo events, foEs increased while fbEs decreased, so that the difference foEs-fbEs was enhanced, indicating the development of strong spatial structuring in electron density within a sporadic E-layer. On the other hand, increases in sporadic E range spreading also correlated with the occurrence of QP echoes but the degree of correlation varied from event to event. Continuous radar echoes were observed in association with low altitude sporadic E-layers, located well below 100 km and at times as low as 90 km. During the continuous echo events, both foEs and fbEs were less variable, and the difference foEs-fbEs was small and not as dynamic as in the QP echoes. On the other hand, the Es-layer spread intensified during continuous echoes, which means that some patchiness or corrugation in those low altitude layers is also necessary for the continuous backscatter echoes to take place.

  3. Simultaneous observation of sporadic E with a rapid-run ionosonde and VHF coherent backscatter radar

    Directory of Open Access Journals (Sweden)

    T. Maruyama

    2006-03-01

    Full Text Available During the SEEK 2 rocket campaign, ionograms were recorded every minute at the Yamagawa Radio Observatory at about 90km west of the region monitored by a VHF (very high frequency coherent backscatter radar. Sporadic E-layer parameters, which include the critical (foEs and blanketing (fbEs frequencies, the layer height (h'Es, and the width of the range spread of sporadic E-traces, were compared with RTI (range-time-intensity plots of VHF quasi-periodic (QP and continuous coherent backscatter echoes. A close relationship was found between the appearance of QP echoes in the RTI plots and the level of spatial inhomogeneity in sporadic E plasma, signified here by the difference between foEs and fbEs. During QP echo events, foEs increased while fbEs decreased, so that the difference foEs-fbEs was enhanced, indicating the development of strong spatial structuring in electron density within a sporadic E-layer. On the other hand, increases in sporadic E range spreading also correlated with the occurrence of QP echoes but the degree of correlation varied from event to event. Continuous radar echoes were observed in association with low altitude sporadic E-layers, located well below 100 km and at times as low as 90 km. During the continuous echo events, both foEs and fbEs were less variable, and the difference foEs-fbEs was small and not as dynamic as in the QP echoes. On the other hand, the Es-layer spread intensified during continuous echoes, which means that some patchiness or corrugation in those low altitude layers is also necessary for the continuous backscatter echoes to take place.

  4. Recent Comparisons of VHF Lightning Mapping Using Interferometry and Time-of-Arrival Techniques

    Science.gov (United States)

    Lojou, J.; Cummins, K. L.

    2005-12-01

    As part of Vaisala's technology and applications test bed in the Dallas-Fort Worth area in Texas, we have been operating two overlapping Total Lightning detection networks. One network employs VHF Interferometry (both 2- and 3-timensional instrumentation) and the other employs VHF 3-dimensional Time-Of-Arrival (TOA) techniques. For the first time, these two technologies can be compared and contrasted in a common region where they both exhibit good performance. The aim of the work presented is to evaluate the spatial and temporal "description" of lightning flashes provided by these two techniques, and to compare and contrast the relative strengths of these two approaches for Total Lightning mapping. This study employs data acquired during the summer of 2005. The analysis set includes data obtained by these two networks, as well as cloud-to-ground location data from the U.S. National Lightning Detection Network (NLDN). The spatial extent and vertical profile of sources from individual in-cloud and cloud-to-ground flashes are compared for various storm conditions, with both technologies clearly contributing supplemental information not provided by the other. Leader propagation velocities show a substantially unimodal distribution centered at about 105 m/s for TOA-derived sources, whereas the velocity distribution for sources detected using interferometry exhibit a bimodal distribution with the second mode at about 107 m/s. The most-probable interval-between-sources for TOA-derived sources seems to be a few milliseconds, whereas interferometry produces large populations with intervals near 100 microseconds and 100 milliseconds.

  5. Radon measurements aboard the Kuiper Airborne Observatory

    Science.gov (United States)

    Kritz, Mark A.; Rosner, Stefan W.

    1995-01-01

    We have carried out three (piggyback) radon-related projects aboard the KAO. The first, which was limited to upper tropospheric measurements while in level flight, revealed the systematic occurrence of unexpectedly high radon concentrations in this region of the atmosphere. The second project was an instrument development project, which led to the installation of an automatic radon measurement system aboard the NASA ER-2 High Altitude Research Aircraft. In the third, we installed a new system capable of collecting samples during the normal climb and descent of the KAO. The results obtained in these projects have resulted in significant contributions to our knowledge of atmospheric transport processes, and are currently playing a key role in the validation of global circulation and transport models.

  6. Complex researches aboard the international space station

    Science.gov (United States)

    Pokhyl, Yu. A.

    Special Research and Development Bureau SRDB is a general organizer on Ukrainian part of three Ukrainian- Russian joint experiments to be implemented aboard the Russian segment of International Space Station RS-ISS Experiment Material- Friction It is proposed to carry out a series of comparative tribological research under conditions of orbital flight aboard the ISS versus those in on- ground laboratory conditions To meet these objectives there will be employed a special onboard 6-module Space- borne tribometer- facility The on- ground research will be implemented under conditions of laboratory simulation of Space environmental factors Results thus obtained would enable one to forecast a behavior of friction pairs as well as functional safety and lifetime of the space- vehicle This experiment will also enable us determine an adequacy of tribological results obtained under conditions of outer Space and on- ground simulation Experiment Penta- Fatigue It is proposed to develop fabricate and deliver aboard the RS-ISS a facility intended for studies of SEF- influence on characteristics of metallic and polymeric materials resistance to fatigue destruction Such a project to be implemented in outer Space for the first ever time would enable us to estimate the parameter of cosmic lifetime for constructional materials due to such mechanical characteristic as fatigue strength so as to enable selection of specific sorts of constructional materials appropriate to service in Space technologies At the same time

  7. Analysis of the VHF-UHF electromagnetic radiation of lightning: Application to a model of the negative stepped leader propagation

    Science.gov (United States)

    Taudiere, Isabelle

    1991-03-01

    The space and time characteristics of the VHF-UHF radiation from lightning are analyzed on the bases of 300 MHz emission sources, localized in three dimensions by interferometric measurements. The main phases that contribute to the development of intracloud lightning are examined in detail, also using electric field measurements at the lower frequency. This research is complemented by an experimental and theoretical analysis of long discharge (8m) radio emissions generated with both polarities in the laboratory. These investigations revealed that the VHF radiation is associated with the channel reillumination phase accompanying each step in the negative spark. The outcome of this work is the creation of a simple model for the propagation of the negative leader. The current and the radiated field during this phase of the discharge are computed from an equivalent electric circuit using the physical laws governing the variation of resistance. The extrapolation of these results to the case of the stepped leader of natural lightning is discussed.

  8. Meteor head echo altitude distributions and the height cutoff effect studied with the EISCAT HPLA UHF and VHF radars

    Directory of Open Access Journals (Sweden)

    A. Westman

    2004-04-01

    Full Text Available Meteor head echo altitude distributions have been derived from data collected with the EISCAT VHF (224MHz and UHF (930MHz high-power, large-aperture (HPLA radars. At the high-altitude end, the distributions cut off abruptly in a manner reminiscent of the trail echo height ceiling effect observed with classical meteor radars. The target dimensions are shown to be much smaller than both the VHF and the UHF probing wavelengths, but the cutoff heights for the two systems are still clearly different, the VHF cutoff being located several km above the UHF one. A single-collision meteor-atmosphere interaction model is used to demonstrate that meteors in the (1.3–7.2µg mass range will ionise such that critical electron density at 224MHz is first reached at or around the VHF cutoff altitude and critical density at 930MHz will be reached at the UHF cutoff altitude. The observed seasonal variation in the cutoff altitudes is shown to be a function of the seasonal variation of atmospheric density with altitude. Assuming that the electron density required for detection is in the order of the critical density, the abrupt altitude cutoffs can be explained as a consequence of the micrometeoroid joint size-speed distribution dropping off so fast at the large-mass, high-velocity end that above a certain altitude the number of detectable events becomes vanishingly small. Conversely, meteors at the low-mass end of the distribution will be gradually retarded such that the ionisation they generate never reaches critical density. These particles will remain unobservable.Key words. Radio science (instruments and techniques – Interplatery physics (interplanetary dust – General or miscellaneous (new fields

  9. Observations of VHF emissions from 50-mA electron beam injections in the ionosphere that are associated with beam-induced discharges

    Science.gov (United States)

    Goerke, R. T.; Kellogg, P. J.; Monson, S. J.; Franz, R. C.; Nemzek, R. J.; Anderson, H. R.; Potter, D. W.; Denig, W. F.; Szuszczewicz, E. P.; Earle, G. D.

    1992-01-01

    Results are presented of observations of strong VHF plasma waves with amplitudes in excess of 0.1 mV/m (Hz)1/2 associated with 50 mA electron beam injections in the ionosphere. Data from three swept-frequency receivers carried on two daughter payloads are analyzed to determine the emission spectra of the electron beam for various energies and currents. These results were obtained from the rocket-borne experiment SCEX 3, NASA flight 39.002 UE, launched February 1, 1990. The accelerator payload also carried photometers, which measured luminosity at wavelengths of 391.4 and 380.5 nm. Several times during electron gun activity the measured luminosity increased much faster than proportional to the beam current. This nonlinear increase is evidence that a discharge is occurring in the vicinity of the accelerator payload. It is inferred from the uniform distribution of the luminosity around the accelerator payload that the observed discharge extends significantly outside the beam cylinder.

  10. VHF digital ultrasound three-dimensional scanning in the diagnosis of myopic regression after corneal refractive surgery.

    Science.gov (United States)

    Reinstein, Dan Z; Ameline, Barbara; Puech, Michel; Montefiore, Guy; Laroche, Laurent

    2005-01-01

    To perform VHF digital ultrasound scanning and analysis of a case of high-myopic undercorrection in an eye that had undergone multiple surgical interventions for the correction of an initial refraction of -12.00 diopters (D). A 49-year-old woman was evaluated after undergoing three surgical interventions for correction of an initial refraction of -12.00 D in the left eye. Automated lamellar keratoplasty (ALK) was followed by arcuate keratotomy (for induced astigmatism) and surface photorefractive keratectomy (PRK). The residual ametropia on presentation was -6.75 -3.50 x 95 degrees. VHF digital ultrasound scanning and analysis was performed. On ultrasound, the ALK interface was clearly visible. Residual stromal thickness beneath the cap was at least 275 microm. The absence of Bowman's layer indicated the region of PRK. New stroma and nascent stromal layers were differentiated within the flap. Neo stromal deposition and central epithelial hyperplasia were determined to be responsible for the myopic shift, as opposed to biomechanical changes. In this case, refraction, slit-lamp examination, and topography were unable to provide a diagnosis for regression following multiple corneal refractive procedures. By providing layered anatomical mapping, VHF digital ultrasound scanning was able to exclude a diagnosis of ectasia and provide anatomical diagnostic information to explain the clinical observations.

  11. Disturbances in VHF/UHF telemetry links as a possible effect of the 2003 Hokkaido Tokachi-oki earthquake

    Directory of Open Access Journals (Sweden)

    H. Nagamoto

    2008-08-01

    Full Text Available The data on radio telemetry links (for water information at VHF/UHF in Hokkaido are used to investigate the rate of disturbances on radio links (or connection failure and its association with a huge earthquake, Tokachi-oki earthquake on 26 September 2003. Especially, the telemetry links at the Tokachi region closest to the earthquake epicenter, showed a significant increase in disturbances on radio links two weeks to a few days before the earthquake on the basis of analysis during a long interval from 1 June 2002 to 3 November 2007 (over 5 years. We suggest that these severe disturbances in VHF/UHF telemetry links are attributed to the generation of seismogenic VHF/UHF radio noises (emissions. Based on this idea, we have estimated that the intensity of these seismogenic emissions is on the order of 10–19 dB μV/m. Finally, the present result was compared with other physical parameters already obtained for this earthquake.

  12. First results from an iron lidar and a VHF radar at Davis, Antarctica

    Science.gov (United States)

    Luebken, F.; Morris, R. J.; Hoeffner, J.; Kaifler, B.; Viehl, T.

    2012-12-01

    We present temperature measurements at Davis, Antarctica (69°S, 78°E), and compare with simultaneous and co-located radar measurements of polar mesosphere summer echoes (PMSE). The mobile scanning iron lidar of the IAP in Kuehlungsborn was installed at Davis in December 2010. It measures iron densities, vertical winds, and temperatures in the iron layer, i. e. from approximately 80 to 100 km. It is based on probing the Doppler broadened resonance line of iron atoms at 386 nm and can operate under daylight conditions. Typical values for temperature uncertainty, altitude and time resolution are 3-5 K, 1 km, and 1 hour, respectively. The lidar also measures neutral air densities and temperatures in the stratosphere and lower mesosphere. At Davis the lidar has up to now achieved approximately 2700 hours of data which is presumably the largest nearly continuous data set in Antarctica. The mesopause altitude changes throughout the summer season by several kilometers, significantly different from the northern hemisphere summer. Depending on altitude, temperatures can be warmer or colder compared to the NH summer. Temperatures at Davis near 86 km are rather similar to the NH, but they are much colder at higher altitudes. The thermal structure around the mesopause at Davis is closely related to the general circulation in the stratosphere, namely to the transition from winter to summer conditions. Different from expectations we sometimes find the mesopause significantly higher and colder(!) compared to the NH. Furthermore, we find large thermal tides in the summer months with amplitudes of up to 6-7~K, which is much larger than expected from models. The Australien Antarctic Division operates a 55 MHz VHF radar at Davis since February 2003. We report first simultaneous measurements of PMSE and temperatures by the Fe lidar. PMSE are strong radar echoes related to ice particles and therefore require atmospheric temperatures being lower than the frost point temperature

  13. Long-period unstable gravity-waves and associated VHF radar echoes

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    Full Text Available VHF atmospheric radar is used to measure the wind velocity and radar echo power related to long-period wind perturbations, including gravity waves, which are observed commonly in the lower stratosphere and tropopause region, and sometimes in the troposphere. These wind structures have been identified previously as either inertia-gravity waves, often associated with jet streams, or mountain waves. At heights of peak wind shear, imbalances are found between the echo powers of a symmetric pair of radar beams, which are expected to be equal. The largest of these power differences are found for conditions of simultaneous high wind shear and high aspect sensitivity. It is suggested that the effect might arise from tilted specular reflectors or anisotropic turbulent scatterers, a result of, for example, Kelvin-Helmholtz instabilities generated by the strong wind shears. This radar power-difference effect could offer information about the onset of saturation in long-period waves, and the formation of thin layers of turbulence.

  14. Anisotropy of Doppler spectral parameters in the VHF radar observations at MU and White Sands

    Directory of Open Access Journals (Sweden)

    G. D. Nastrom

    2001-08-01

    Full Text Available Significant differences are found between the mean spectral widths from beams in the meridional plane and in the zonal plane at both the MU and the White Sands VHF radars. The spectral width in the beam directed perpendicular to the prevailing wind is greater than that in the beam parallel to the wind. The magnitudes of the differences in spectral width show a linear relationship with wind speed, with the greatest differences at the greatest wind speeds. The differences in spectral width show a positive correlation with the differences in backscattered power. The anisotropy in backscattered power is well-known and is usually attributed to aspect sensitivity effects. However, the anisotropy in spectral width does not appear to be due to the same mechanism, and while several hypotheses to account for this are considered, including finite range-volume effects, effects from the tilting of isentropic layers, and anisotropic turbulence effects, it is seen that each of these suggestions has its shortcomings.Key words. Meteorology and atmospheric dynamics (turbulence; instruments and techniques

  15. Anisotropy of Doppler spectral parameters in the VHF radar observations at MU and White Sands

    Directory of Open Access Journals (Sweden)

    G. D. Nastrom

    Full Text Available Significant differences are found between the mean spectral widths from beams in the meridional plane and in the zonal plane at both the MU and the White Sands VHF radars. The spectral width in the beam directed perpendicular to the prevailing wind is greater than that in the beam parallel to the wind. The magnitudes of the differences in spectral width show a linear relationship with wind speed, with the greatest differences at the greatest wind speeds. The differences in spectral width show a positive correlation with the differences in backscattered power. The anisotropy in backscattered power is well-known and is usually attributed to aspect sensitivity effects. However, the anisotropy in spectral width does not appear to be due to the same mechanism, and while several hypotheses to account for this are considered, including finite range-volume effects, effects from the tilting of isentropic layers, and anisotropic turbulence effects, it is seen that each of these suggestions has its shortcomings.

    Key words. Meteorology and atmospheric dynamics (turbulence; instruments and techniques

  16. Frequency domain interferometry mode observations of PMSE using the EISCAT VHF radar

    Directory of Open Access Journals (Sweden)

    P. B. Chilson

    2000-12-01

    Full Text Available During the summer of 1997 investigations into the nature of polar mesosphere summer echoes (PMSE were conducted using the European incoherent scatter (EISCAT VHF radar in Norway. The radar was operated in a frequency domain interferometry (FDI mode over a period of two weeks to study the frequency coherence of the returned radar signals. The operating frequencies of the radar were 224.0 and 224.6 MHz. We present the first results from the experiment by discussing two 4-h intervals of data collected over two consecutive nights. During the first of the two days an enhancement of the FDI coherence, which indicates the presence of distinct scattering layers, was found to follow the lower boundary of the PMSE. Indeed, it is not unusual to observe that the coherence values are peaked around the heights corresponding to both the lower- and upper-most boundaries of the PMSE layer and sublayers. A Kelvin-Helmholtz mechanism is offered as one possible explanation for the layering structure. Additionally, our analysis using range-time-pseudocolor plots of signal-to-noise ratios, spectrograms of Doppler velocity, and estimates of the positions of individual scattering layers is shown to be consistent with the proposition that upwardly propagating gravity waves can become steepened near the mesopause.Key words: Ionosphere (polar ionosphere · Meteorology and Atmospheric Dynamics (middle atmosphere dynamics · Radio Science (Interferometry

  17. Frequency domain interferometry mode observations of PMSE using the EISCAT VHF radar

    Directory of Open Access Journals (Sweden)

    P. B. Chilson

    Full Text Available During the summer of 1997 investigations into the nature of polar mesosphere summer echoes (PMSE were conducted using the European incoherent scatter (EISCAT VHF radar in Norway. The radar was operated in a frequency domain interferometry (FDI mode over a period of two weeks to study the frequency coherence of the returned radar signals. The operating frequencies of the radar were 224.0 and 224.6 MHz. We present the first results from the experiment by discussing two 4-h intervals of data collected over two consecutive nights. During the first of the two days an enhancement of the FDI coherence, which indicates the presence of distinct scattering layers, was found to follow the lower boundary of the PMSE. Indeed, it is not unusual to observe that the coherence values are peaked around the heights corresponding to both the lower- and upper-most boundaries of the PMSE layer and sublayers. A Kelvin-Helmholtz mechanism is offered as one possible explanation for the layering structure. Additionally, our analysis using range-time-pseudocolor plots of signal-to-noise ratios, spectrograms of Doppler velocity, and estimates of the positions of individual scattering layers is shown to be consistent with the proposition that upwardly propagating gravity waves can become steepened near the mesopause.

    Key words: Ionosphere (polar ionosphere · Meteorology and Atmospheric Dynamics (middle atmosphere dynamics · Radio Science (Interferometry

  18. Study of CNT growth using nanocatalyst Ag precursor by HWC-VHF-PECVD

    Energy Technology Data Exchange (ETDEWEB)

    Eliyana, Ajeng; Rosikin, Ahmad; Winata, Toto, E-mail: toto@fi.itb.ac.id [Physics of Electronics Material Research Division, Physics Programme, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, West Java (Indonesia)

    2015-04-16

    The study of CNT growth has been done by using silver (Ag) nanocatalyst as a guide precursor on corning glass 7059 substrate. The silver catalyst was prepared by the evaporation method by varying deposition time for 50, 25, and 14 seconds. The silver films were then annealed at temperature of 400°C for 4 hours. From Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) results the grain sizes are 65 nm, 57 nm, and 33 nm, and also the atomic compositions are 6,06%, 4,52%, and 3,73% for 14, 25 and 50 seconds samples, respectively. The 33 nm samples were then used for CNT growth by using Hot Wire Cell (HWC) – Very High Frequency (VHF) – Plasma Enhanced Chemical Vapor Deposition (PECVD) at 275 ° C deposition temperature and pressure of 300 mTorr. The rf power was varied from 8 to 20 watts, with deposition time for 60 minutes. The methane (CH4) 99.999% was used as Carbon sources. Hydrogen gas (H2) was used to etch the oxide layer formed during the pre-deposition process. The diameter and length for the CNT are 125 nm and 1.650 to 2.989 nm respectively.

  19. On the VHF source retrieval errors associated with Lightning Mapping Arrays (LMAs)

    Science.gov (United States)

    Koshak, W. J.

    2016-12-01

    A common method for retrieving the lightning Very High Frequency (VHF) radio source (x, y, z, t) emission is to minimize a (reduced) chi-squared function that indicates how well the model arrival times associated with the model source represent the arrival time measurements at each Lightning Mapping Array (LMA) site. The Levenberg-Marquardt (LM) algorithm is usually employed to find the minimum of the chi-squared function, and the model source producing this minimum is considered to be the optimal source solution. Because the chi-squared mathematical surface is nonlinear, it is important to feed the LM algorithm an accurate initial guess (xo, yo, zo, to) in parameter space to avoid parameter searches that terminate at a relative minima of the chi-squared surface. Source initialization is commonly performed using a linear retrieval algorithm first introduced in Koshak and Solakiewicz (1996), and further applied in Koshak et al. (2004). Monte Carlo simulations and theoretical inferences both show that source retrieval errors (particularly source altitude errors) increase with horizontal source range. In the present study, the effect of modifying certain elements of the retrieval (i. e., the LMA site locations, the number of sites employed, and the retrieval algorithm characteristics) are examined to assess and quantify associated improvements in retrieval results.

  20. Signal processing techniques for phase-coded HF-VHF radars

    Directory of Open Access Journals (Sweden)

    J. A. Baskaradas

    2003-06-01

    Full Text Available HF-VHF radar techniques are easy to employ and commonly used in geophysical applications. They include deep radio soundings, used for probing the ionosphere, stratosphere-mesosphere measurement, weather forecast and radio-glaciology. Fast algorithms and powerful processors facilitate the development of several kinds of low power radars, but the reduction of the transmitted power has to be compensated by on-line processing of an encoded signal to maintain a favorable signal-to-noise ratio suitable for detection. Moreover, radars have to reconstruct return echoes with different travel times due to various origins (multi-path, adjacent objects, etc.. Such needs can be accomplished by means of signal phase coding and one of the most attractive is the reversal phase code. The composite echo signal must be processed to extract the physical information useful for the measurement considered. In this paper some algorithms used for on-line processing of phase-coded signals will be described, both in time and frequency domain.

  1. Surgery aboard ship: is it safe?

    Science.gov (United States)

    Fontana, M; Lucha, P; Snyder, M; Liston, W

    1999-09-01

    A retrospective review was performed on 684 surgical procedures done aboard U.S. Atlantic Fleet ships during a 3-year period from 1994 to 1996. These procedures were compared with similar procedures performed at the Naval Medical Center in Portsmouth, Virginia. Morbidity and mortality rates were calculated and compared. A very low morbidity rate (0.43%) was reported for surgical procedures performed while deployed compared with 1.69% for procedures at the Naval Medical Center. One mortality was reported. These extremely low rates are felt to be attributable to multiple causes, including a highly selected, healthy patient population, performance of only low-risk procedures, early presentation of surgical problems, and early medical evacuation of patients with complex medical and surgical problems. We feel that elective surgical procedures such as vasectomy, circumcision, inguinal hernia repair, and hemorrhoidectomy can be performed safely aboard ship. This would increase the training opportunity for all members of the medical department and at the same time decrease the costs and risks associated with medical evacuation.

  2. Arctic and Antarctic polar mesosphere summer echoes observed with oblique incidence HF radars: analysis using simultaneous MF and VHF radar data

    Directory of Open Access Journals (Sweden)

    T. Ogawa

    2004-12-01

    Full Text Available Polar mesosphere summer echoes (PMSEs have been well studied using vertical incidence VHF radars at northern high-latitudes. In this paper, two PMSE events detected with the oblique incidence SuperDARN HF radars at Hankasalmi, Finland (62.3° N and Syowa Station, Antarctica (69.0° S, are analyzed, together with simultaneous VHF and medium-frequency (MF radar data. Altitude resolutions of the HF radars in the mesosphere and the lower thermosphere are too poor to know exact PMSE altitudes. However, a comparison of Doppler velocity from the HF radar and neutral wind velocity from the MF radar shows that PMSEs at the HF band appeared at altitudes within 80-90km, which are consistent with those from previous vertical incidence HF-VHF radar results. The HF-VHF PMSE occurrences exhibit a semidiurnal behavior, as observed by other researchers. It is found that in one event, PMSEs occurred when westward semidiurnal winds with large amplitude at 85-88km altitudes attained a maximum. When the HF-VHF PMSEs were observed at distances beyond 180km from MF radar sites, the MF radars detected no appreciable signatures of echo enhancement. Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; thermospheric dynamics; waves and tides

  3. Arctic and Antarctic polar mesosphere summer echoes observed with oblique incidence HF radars: analysis using simultaneous MF and VHF radar data

    Directory of Open Access Journals (Sweden)

    T. Ogawa

    2004-12-01

    Full Text Available Polar mesosphere summer echoes (PMSEs have been well studied using vertical incidence VHF radars at northern high-latitudes. In this paper, two PMSE events detected with the oblique incidence SuperDARN HF radars at Hankasalmi, Finland (62.3° N and Syowa Station, Antarctica (69.0° S, are analyzed, together with simultaneous VHF and medium-frequency (MF radar data. Altitude resolutions of the HF radars in the mesosphere and the lower thermosphere are too poor to know exact PMSE altitudes. However, a comparison of Doppler velocity from the HF radar and neutral wind velocity from the MF radar shows that PMSEs at the HF band appeared at altitudes within 80-90km, which are consistent with those from previous vertical incidence HF-VHF radar results. The HF-VHF PMSE occurrences exhibit a semidiurnal behavior, as observed by other researchers. It is found that in one event, PMSEs occurred when westward semidiurnal winds with large amplitude at 85-88km altitudes attained a maximum. When the HF-VHF PMSEs were observed at distances beyond 180km from MF radar sites, the MF radars detected no appreciable signatures of echo enhancement.

    Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; thermospheric dynamics; waves and tides

  4. Effect of solar and magnetic activity on VHF scintillations near the equatorial anomaly crest

    Directory of Open Access Journals (Sweden)

    R. P. Singh

    2004-09-01

    Full Text Available The VHF amplitude scintillation recorded during the period January 1991 to December 1993 in the declining phase of a solar cycle and April 1998 to December 1999 in the ascending phase of the next solar cycle at Varanasi (geogr. lat.=25.3°, long.=83.0°, dip=37°N have been analyzed to study the behavior of ionospheric irregularities during active solar periods and magnetic storms. It is shown that irregularities occur at arbitrary times and may last for <30min. A rise in solar activity increases scintillations during winter (November-February and near equinoxes (March-April; September-October, whereas it depresses the scintillations during the summer (May-July. In general, the role of magnetic activity is to suppress scintillations in the pre-midnight period and to increase it in the post-midnight period during equinox and winter seasons, whilst during summer months the effect is reversed. The pre-midnight scintillation is sometimes observed when the main phase of Dst corresponds to the pre-midnight period. The annual variation shows suppression of scintillations on disturbed days, both during pre-midnight and post-midnight period, which becomes more effective during years of high solar activity. It is observed that for magnetic storms for which the recovery phase starts post-midnight, the probability of occurrence of irregularities is enhanced during this time. If the magnetic storm occurred during daytime, then the probability of occurrence of scintillations during the night hours is decreased. The penetration of magnetospheric electric fields to the magnetic equator affects the evolution of low-latitude irregularities. A delayed disturbance dynamo electric field also affects the development of irregularities.

  5. Simulation of Controller Pilot Data Link Communications over VHF Digital Link Mode 3

    Science.gov (United States)

    Bretmersky, Steven C.; Murawski, Robert; Nguyen, Thanh C.; Raghavan, Rajesh S.

    2004-01-01

    The Federal Aviation Administration (FAA) has established an operational plan for the future Air Traffic Management (ATM) system, in which the Controller Pilot Data Link Communications (CPDLC) is envisioned to evolve into digital messaging that will take on an ever increasing role in controller to pilot communications, significantly changing the way the National Airspace System (NAS) is operating. According to FAA, CPDLC represents the first phase of the transition from the current analog voice system to an International Civil Aviation Organization (ICAO) compliant system in which digital communication becomes the alternate and perhaps primary method of routine communication. The CPDLC application is an Air Traffic Service (ATS) application in which pilots and controllers exchange messages via an addressed data link. CPDLC includes a set of clearance, information, and request message elements that correspond to existing phraseology employed by current Air Traffic Control (ATC) procedures. These message elements encompass altitude assignments, crossing constraints, lateral deviations, route changes and clearances, speed assignments, radio frequency assignments, and various requests for information. The pilot is provided with the capability to respond to messages, to request clearances and information, to report information, and to declare/rescind an emergency. A 'free text' capability is also provided to exchange information not conforming to defined formats. This paper presents simulated results of the aeronautical telecommunication application Controller Pilot Data Link Communications over VHF Digital Link Mode 3 (VDL Mode 3). The objective of this simulation study was to determine the impact of CPDLC traffic loads, in terms of timely message delivery and capacity of the VDL Mode 3 subnetwork. The traffic model is based on and is used for generating air/ground messages with different priorities. Communication is modeled for the en route domain of the Cleveland

  6. Seasonal and diurnal changes in wind variability from Flatland VHF profiler observations

    Energy Technology Data Exchange (ETDEWEB)

    Nastrom, G.D. [Saint Cloud State Univ., MN (United States). Dept. of Earth Sci.; Clark, W.L. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Aeronomy Lab.; Zandt, T.E. van [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Aeronomy Lab.; Warnock, J.M. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Aeronomy Lab.

    1996-02-01

    Climatological results are presented on the hourly variance of the wind observed in the mid-troposphere (3 to 9 km MSL). This quantity roughly indicates the energy in the atmospheric wind field for variations with periods roughly less than 1 hour. Observations are from the Flatland VHF research wind profiler, located near Champaign/Urbana, Illinois, well away from significant orographic features. The period of record covers two years, September 1990 through August 1992. The values of the variance of the winds along vertical and oblique (15 degrees from zenith in the cardinal directions) beams are presented versus height, season, time-of-day, and beam pointing direction. It is found that the hourly variance values have approximately lognormal frequency distribution. The mean hourly variance is significantly larger for the oblique wind observations than for the vertical. Mean wind variances also tend to be larger in the east/west steering plane than in the north/south plane. The mean variance generally increases with height, but faster than would be expected if it were due solely to the decrease in atmospheric density, implying the presence of local source/sinks of wind energy. The rate of change with height is noticeably different for the vertical and oblique beams, being much less for the vertical beam, in some seasons even decreasing with height. With respect to season, the mean hourly variance is smallest in the summer and largest in the winter. With respect to diurnal changes, the variance is maximum during the afternoon for spring, summer, and autumn, with the maximum up to a factor of two larger than the minimum. In winter, the diurnal change is much smaller, with little indication of an afternoon maximum. (orig.)

  7. VHF radar observations of turbulent structures in the polar mesopause region

    Directory of Open Access Journals (Sweden)

    P. Czechowsky

    Full Text Available The mobile SOUSY VHF Radar was operated in the summer of 1987 during the MAC/SINE campaign in northern Norway to study the polar mesosphere summer echoes (PMSE. Measurements of the spectral width indicate that two types of structures occur. In general mesospheric layers are bifurcated exhibiting a narrow spectral width and a well-defined aspect sensitivity. However, for about 10% of the observation time cells of enhanced turbulence characterized by extremely broad spectral widths appear predominantly in the upper sublayer above 86 km. Identification and separation of beam and shear broadening allows a determination of the turbulence-induced component of the spectral width. This case study reveals that during several events these cloud-like structures of enhanced turbulence move with an apparent velocity of several tens of meters per second which is almost identical with the phase trace velocity of simultaneously observed waves. Since, at that time, the Richardson number was less than a quarter, it was concluded that these turbulent cells were generated by a Kelvin-Helmholtz mechanism. The horizontal extent of these structures was calculated to be less than 40 km. A general relation between spectral width and echo power was not detected. The turbulent component of the spectral width was used to calculate typical values of the energy dissipation rate at times where narrow spectral width dominates and during periods of enhanced turbulence. In addition, the outer scale of the inertial subrange (buoyancy scale was estimated. For the first time the occurrence and motion of this type of structures of enhanced spectral width is analyzed and discussed in detail.

  8. VHF radar observations of turbulent structures in the polar mesopause region

    Directory of Open Access Journals (Sweden)

    P. Czechowsky

    1997-08-01

    Full Text Available The mobile SOUSY VHF Radar was operated in the summer of 1987 during the MAC/SINE campaign in northern Norway to study the polar mesosphere summer echoes (PMSE. Measurements of the spectral width indicate that two types of structures occur. In general mesospheric layers are bifurcated exhibiting a narrow spectral width and a well-defined aspect sensitivity. However, for about 10% of the observation time cells of enhanced turbulence characterized by extremely broad spectral widths appear predominantly in the upper sublayer above 86 km. Identification and separation of beam and shear broadening allows a determination of the turbulence-induced component of the spectral width. This case study reveals that during several events these cloud-like structures of enhanced turbulence move with an apparent velocity of several tens of meters per second which is almost identical with the phase trace velocity of simultaneously observed waves. Since, at that time, the Richardson number was less than a quarter, it was concluded that these turbulent cells were generated by a Kelvin-Helmholtz mechanism. The horizontal extent of these structures was calculated to be less than 40 km. A general relation between spectral width and echo power was not detected. The turbulent component of the spectral width was used to calculate typical values of the energy dissipation rate at times where narrow spectral width dominates and during periods of enhanced turbulence. In addition, the outer scale of the inertial subrange (buoyancy scale was estimated. For the first time the occurrence and motion of this type of structures of enhanced spectral width is analyzed and discussed in detail.

  9. The relationship between VHF radar auroral backscatter amplitude and Doppler velocity: a statistical study

    Directory of Open Access Journals (Sweden)

    B. A. Shand

    1996-08-01

    Full Text Available A statistical investigation of the relationship between VHF radar auroral backscatter intensity and Doppler velocity has been undertaken with data collected from 8 years operation of the Wick site of the Sweden And Britain Radar-auroral Experiment (SABRE. The results indicate three different regimes within the statistical data set; firstly, for Doppler velocities <200 m s–1, the backscatter intensity (measured in decibels remains relatively constant. Secondly, a linear relationship is observed between the backscatter intensity (in decibels and Doppler velocity for velocities between 200 m s–1 and 700 m s–1. At velocities greater than 700 m s–1 the backscatter intensity saturates at a maximum value as the Doppler velocity increases. There are three possible geophysical mechanisms for the saturation in the backscatter intensity at high phase speeds: a saturation in the irregularity turbulence level, a maximisation of the scattering volume, and a modification of the local ambient electron density. There is also a difference in the dependence of the backscatter intensity on Doppler velocity for the flow towards and away from the radar. The results for flow towards the radar exhibit a consistent relationship between backscatter intensity and measured velocities throughout the solar cycle. For flow away from the radar, however, the relationship between backscatter intensity and Doppler velocity varies during the solar cycle. The geometry of the SABRE system ensures that flow towards the radar is predominantly associated with the eastward electrojet, and flow away is associated with the westward electrojet. The difference in the backscatter intensity variation as a function of Doppler velocity is attributed to asymmetries between the eastward and westward electrojets and the geophysical parameters controlling the backscatter amplitude.

  10. Statistics of 150-km echoes over Jicamarca based on low-power VHF observations

    Directory of Open Access Journals (Sweden)

    J. L. Chau

    2006-07-01

    Full Text Available In this work we summarize the statistics of the so-called 150-km echoes obtained with a low-power VHF radar operation at the Jicamarca Radio Observatory (11.97 S, 76.87 W, and 1.3 dip angle at 150-km altitude in Peru. Our results are based on almost four years of observations between August 2001 and July 2005 (approximately 150 days per year. The majority of the observations have been conducted between 08:00 and 17:00 LT. We present the statistics of occurrence of the echoes for each of the four seasons as a function of time of day and altitude. The occurrence frequency of the echoes is ~75% around noon and start decreasing after 15:00 LT and disappear after 17:00 LT in all seasons. As shown in previous campaign observations, the 150-echoes appear at a higher altitude (>150 km in narrow layers in the morning, reaching lower altitudes (~135 km around noon, and disappear at higher altitudes (>150 km after 17:00 LT. We show that although 150-km echoes are observed all year long, they exhibit a clear seasonal variability on altitudinal coverage and the percentage of occurrence around noon and early in the morning. We also show that there is a strong day-to-day variability, and no correlation with magnetic activity. Although our results do not solve the 150-km riddle, they should be taken into account when a reasonable theory is proposed.

  11. The relationship between VHF radar auroral backscatter amplitude and Doppler velocity: a statistical study

    Directory of Open Access Journals (Sweden)

    B. A. Shand

    Full Text Available A statistical investigation of the relationship between VHF radar auroral backscatter intensity and Doppler velocity has been undertaken with data collected from 8 years operation of the Wick site of the Sweden And Britain Radar-auroral Experiment (SABRE. The results indicate three different regimes within the statistical data set; firstly, for Doppler velocities <200 m s–1, the backscatter intensity (measured in decibels remains relatively constant. Secondly, a linear relationship is observed between the backscatter intensity (in decibels and Doppler velocity for velocities between 200 m s–1 and 700 m s–1. At velocities greater than 700 m s–1 the backscatter intensity saturates at a maximum value as the Doppler velocity increases. There are three possible geophysical mechanisms for the saturation in the backscatter intensity at high phase speeds: a saturation in the irregularity turbulence level, a maximisation of the scattering volume, and a modification of the local ambient electron density. There is also a difference in the dependence of the backscatter intensity on Doppler velocity for the flow towards and away from the radar. The results for flow towards the radar exhibit a consistent relationship between backscatter intensity and measured velocities throughout the solar cycle. For flow away from the radar, however, the relationship between backscatter intensity and Doppler velocity varies during the solar cycle. The geometry of the SABRE system ensures that flow towards the radar is predominantly associated with the eastward electrojet, and flow away is associated with the westward electrojet. The difference in the backscatter intensity variation as a function of Doppler velocity is attributed to asymmetries between the eastward and westward electrojets and the geophysical parameters controlling the backscatter amplitude.

  12. Cut-off low monitoring by the French VHF-ST-radar network during the ESTIME campaign

    Science.gov (United States)

    Caccia, J.-L.; Bertin, F.; Campistron, B.; Klaus, V.; Pointin, Y.; van Baelen, J.; Wilson, R.

    2000-05-01

    In order to investigate mesoscale strato-tropospheric exchanges, the field campaign `Echanges Stratosphère-Troposphère: Investigations à Moyenne Echelle' was conducted in France from late 1993 to mid 1995 and focused on cut-off low events. It involved the French research network of five VHF (Very High Frequency) ST (Strato-Tropospheric) radars deployed in southern France. Observations corresponding to three Intensive Observing Periods are reported here. The radar data analyzed and discussed are time-height diagrams of the aspect ratio (AR), that is, the vertical to oblique beam-returned power ratio, used for monitoring three cut-off low events. In order to discuss the validity of the method, 506 h of radar AR data were compared with time-height diagrams of the static stability and the humidity obtained from synoptic European Center for Medium-range Weather Forecasts model analyses. A dataset corresponding to 297 h of observations is analyzed and discussed here. It is concluded that the AR is a good tracer to document cut-off low events, including tropopause folding identification and the detection of tropospheric air masses of enhanced stability, in dry or weakly humid cases. On the other hand, although the effects of the specific humidity and its gradients on VHF radar echo power could not be extensively investigated, our results suggest that the same parameter cannot be used at mid- and lower-tropospheric levels when the effects of specific humidity significantly reinforce the moist static stability. It is important to take into account these insights in the context of future observing campaigns in which a network of VHF-ST-radars will be involved, and where their role will be to observe and to document the evolution of upper-level features or potential vorticity streamers, or more generally stratospheric-tropospheric exchanges.

  13. Electronic warfare receivers and receiving systems

    CERN Document Server

    Poisel, Richard A

    2014-01-01

    Receivers systems are considered the core of electronic warfare (EW) intercept systems. Without them, the fundamental purpose of such systems is null and void. This book considers the major elements that make up receiver systems and the receivers that go in them.This resource provides system design engineers with techniques for design and development of EW receivers for modern modulations (spread spectrum) in addition to receivers for older, common modulation formats. Each major module in these receivers is considered in detail. Design information is included as well as performance tradeoffs o

  14. Radar efficiency and the calculation of decade-long PMSE backscatter cross-section for the Resolute Bay VHF radar

    Directory of Open Access Journals (Sweden)

    N. Swarnalingam

    2009-04-01

    Full Text Available The Resolute Bay VHF radar, located in Nunavut, Canada (75.0° N, 95.0° W and operating at 51.5 MHz, has been used to investigate Polar Mesosphere Summer Echoes (PMSE since 1997. PMSE are a unique form of strong coherent radar echoes, and their understanding has been a challenge to the scientific community since their discovery more than three decades ago. While other high latitude radars have recorded strong levels of PMSE activities, the Resolute Bay radar has observed relatively lower levels of PMSE strengths. In order to derive absolute measurements of PMSE strength at this site, a technique is developed to determine the radar efficiency using cosmic (sky noise variations along with the help of a calibrated noise source. VHF radars are only rarely calibrated, but determination of efficiency is even less common. Here we emphasize the importance of efficiency for determination of cross-section measurements. The significant advantage of this method is that it can be directly applied to any MST radar system anywhere in the world as long as the sky noise variations are known. The radar efficiencies for two on-site radars at Resolute Bay are determined. PMSE backscatter cross-section is estimated, and decade-long PMSE strength variations at this location are investigated. It was noticed that the median of the backscatter cross-section distribution remains relatively unchanged, but over the years a great level of variability occurs in the high power tail of the distribution.

  15. Meteoroid Fragmentation as Revealed in Head- and Trail-Echoes Observed with the Arecibo UHF and VHF Radars

    Science.gov (United States)

    Mathews, J. D.; Malhorta, A.

    2011-01-01

    We report recent 46.8/430 MHz (VHF/UHF) radar meteor observations at Arecibo Observatory (AO) that reveal many previously unreported features in the radar meteor return - including flare-trails at both UHF and VHF - that are consistent with meteoroid fragmentation. Signature features of fragmentation include strong intra-pulse and pulse-to-pulse fading as the result of interference between or among multiple meteor head-echo returns and between head-echo and impulsive flare or "point" trail-echoes. That strong interference fading occurs implies that these scatterers exhibit well defined phase centers and are thus small compared with the wavelength. These results are consistent with and offer advances beyond a long history of optical and radar meteoroid fragmentation studies. Further, at AO, fragmenting and flare events are found to be a large fraction of the total events even though these meteoroids are likely the smallest observed by the major radars. Fragmentation is found to be a major though not dominate component of the meteors observed at other HPLA radars that are sensitive to larger meteoroids.

  16. Radiation measurements aboard the fourth Gemini flight.

    Science.gov (United States)

    Janni, J F; Schneider, M F

    1967-01-01

    Two special tissue-equivalent ionization chambers and 5 highly sensitive passive dosimetry packages were flown aboard the recent Gemini 4 flight for the purpose of obtaining precise values of instantaneous dose rate, accumulated dose. and shielding effectiveness. This experiment marked the first time that well-defined tissue dose and radiation survey measurements have been carried out in manned spaceflight operations. Since all measurements were accomplished under normal spacecraft environmental conditions, the biological dose resulted primarily from trapped inner Van Allen Belt radiation encountered by the spacecraft in the South Atlantic Anomaly. The experiment determined the particle type, ionizing and penetrating power, and variation with time and position within the Gemini spacecraft. Measured dose rates ranged from 100 mrad/hr for passes penetrating deeply into the South Atlantic Anomaly to less than 0.1 mrad/hr from lower latitude cosmic radiation. The accumulated tissue dose measured by the active ionization chambers, shielded by 0.4 gm/cm2 for the 4-day mission, was 82 mrad. Since the 5 passive dosimetry packages were each located in different positions within the spacecraft, the total mission surface dose measured by these detectors varied from 73 to 27 mrad, depending upon location and shielding. The particles within the spacecraft were recorded in nuclear emulsion, which established that over 90% of the tissue dose was attributable to penetrating protons. This experiment indicates that the radiation environment under shielded conditions at Gemini altitudes was not hazardous.

  17. First results from the GPS atmosphere sounding experiment TOR aboard the TerraSAR-X satellite

    Directory of Open Access Journals (Sweden)

    G. Beyerle

    2011-07-01

    Full Text Available GPS radio occultation events observed between 24 July and 17 November 2008 by the IGOR occultation receiver aboard the TerraSAR-X satellite are processed and analyzed. The comparison of 15 327 refractivity profiles with collocated ECMWF data yield a mean bias between zero and −0.30 % at altitudes between 5 and 30 km. Standard deviations decrease from about 1.4 % at 5 km to about 0.6 % at 10 km altitude, however, increase significantly in the upper stratosphere. At low latitudes mean biases and standard deviations are larger, in particular in the lower troposphere. The results are consistent with 15 159 refractivity observations collected during the same time period by the BlackJack receiver aboard GRACE-A and processed by GFZ's operational processing system. The main difference between the two occultation instruments is the implementation of open-loop signal tracking in the IGOR (TerraSAR-X receiver which improves the tropospheric penetration depth in terms of ray height by about 2 km compared to the conventional closed-loop data acquired by BlackJack (GRACE-A.

  18. High-Rate Fabrication of a-Si-Based Thin-Film Solar Cells Using Large-Area VHF PECVD Processes

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Xunming [University of Toledo; Fan, Qi Hua

    2011-12-31

    The University of Toledo (UT), working in concert with it’s a-Si-based PV industry partner Xunlight Corporation (Xunlight), has conducted a comprehensive study to develop a large-area (3ft x 3ft) VHF PECVD system for high rate uniform fabrication of silicon absorber layers, and the large-area VHF PECVD processes to achieve high performance a-Si/a-SiGe or a-Si/nc-Si tandem junction solar cells during the period of July 1, 2008 to Dec. 31, 2011, under DOE Award No. DE-FG36-08GO18073. The project had two primary goals: (i) to develop and improve a large area (3 ft × 3 ft) VHF PECVD system for high rate fabrication of > = 8 Å/s a-Si and >= 20 Å/s nc-Si or 4 Å/s a-SiGe absorber layers with high uniformity in film thicknesses and in material structures. (ii) to develop and optimize the large-area VHF PECVD processes to achieve high-performance a-Si/nc-Si or a-Si/a-SiGe tandem-junction solar cells with >= 10% stable efficiency. Our work has met the goals and is summarized in “Accomplishments versus goals and objectives”.

  19. A Low Power RC-Coupled VHF Amplifier Designed for Fabrication by Hybrid Microcircuit Techniques.

    Science.gov (United States)

    RADIOFREQUENCY AMPLIFIERS, HYBRID CIRCUITS, MICROMINIATURIZATION , VERY HIGH FREQUENCY, MODULES(ELECTRONICS), TRANSISTOR AMPLIFIERS, RADIO RECEIVERS, COMMUNICATION EQUIPMENT, SATELLITE COMMUNICATIONS.

  20. Lunar surface reflectance by LALT aboard KAGUYA

    Science.gov (United States)

    Noda, H.; Araki, H.; Ishihara, Y.; Tazawa, S.; Sasaki, S.; Kawano, N.

    2009-12-01

    The Laser Altimeter (LALT) aboard Japanese lunar explorer KAGUYA (SELENE) is a ranging instrument which measures the distance between the satellite and the lunar surface with accuracy of 1 m by detecting the timing delay of the reflected laser light. The main science goal of the LALT is to obtain the lunar global topographic data including polar regions for the study of the origin and the evolution of the Moon [1]. Besides, the LALT is equipped with an intensity monitor of the returned pulses. The intensity of the returned pulses contains information concerning surface roughness and reflectance of the footprints, which will contribute to the study of the lunar surface maturity and age. The reflectance at LALT wavelength (1064nm) is sensitive to the surface maturity and composition. The data should be particularly important at lunar polar regions where camera instruments should suffer from phase angle effects in the surface reflectance and moreover cannot obtain reflectance data at the permanently shadowed area. The normal operation of the LALT began on 30th, December 2007 after two months’ commissioning phase. Before the end of the normal operation phase in October 2008, the LALT measured more than 10 million range data. Unfortunately, due to the laser power decrease and also possible smaller surface reflectance than the expected value before launch (15 % at 1 micro meter), the return pulse intensity during the nominal mission phase is so small that they are not reliable enough to discuss the surface property. During the extended mission phase, which started November 2008, the satellite altitude decreased to 50 km. Due to the malfunction of the reaction wheel and high-voltage instruments were shutdown, the observation was suspended until 11th of February, 2009. LALT successfully resumed observation on 12th February and continued observation until the controlled crash of KAGUYA onto the Moon on 10th of June, 2009. Thanks to the lower orbit during this phase, the

  1. Cryocooled wideband digital channelizing radio-frequency receiver based on low-pass ADC

    Energy Technology Data Exchange (ETDEWEB)

    Vernik, Igor V; Kirichenko, Dmitri E; Dotsenko, Vladimir V; Miller, Robert; Webber, Robert J; Shevchenko, Pavel; Talalaevskii, Andrei; Gupta, Deepnarayan; Mukhanov, Oleg A [HYPRES, Inc., 175 Clearbrook Road, Elmsford, NY 10523 (United States)

    2007-11-15

    We have demonstrated a digital receiver performing direct digitization of radio-frequency signals over a wide frequency range from kilohertz to gigahertz. The complete system, consisting of a cryopackaged superconductor all-digital receiver (ADR) chip followed by room-temperature interface electronics and a field programmable gate array (FPGA) based post-processing module, has been developed. The ADR chip comprises a low-pass analog-to-digital converter (ADC) delta modulator with phase modulation-demodulation architecture together with digital in-phase and quadrature mixer and a pair of digital decimation filters. The chip is fabricated using a 4.5 kA cm{sup -2} process and is cryopackaged using a commercial-off-the-shelf cryocooler. Experimental results in HF, VHF, UHF and L bands and their analysis, proving consistent operation of the cryopackaged ADR chip up to 24.32 GHz clock frequency, are presented and discussed.

  2. Solar heat receiver

    Science.gov (United States)

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  3. A flexible WLAN receiver

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2003-01-01

    Flexible radio receivers are also called Software Defined Radios (SDRs) [1], [2]. The focus of our SDR project [3] is on designing the front end, from antenna to demodulation in bits, of a °exible, multi-standard WLAN receiver. We try to combine an instance of a (G)FSK receiver (Bluetooth) with an

  4. The Epi Info Viral Hemorrhagic Fever (VHF) Application: A Resource for Outbreak Data Management and Contact Tracing in the 2014-2016 West Africa Ebola Epidemic.

    Science.gov (United States)

    Schafer, Ilana J; Knudsen, Erik; McNamara, Lucy A; Agnihotri, Sachin; Rollin, Pierre E; Islam, Asad

    2016-10-15

    The Epi Info Viral Hemorrhagic Fever application (Epi Info VHF) was developed in response to challenges managing outbreak data during four 2012 filovirus outbreaks. Development goals included combining case and contact data in a relational database, facilitating data-driven contact tracing, and improving outbreak data consistency and use. The application was first deployed in Guinea, when the West Africa Ebola epidemic was detected, in March 2014, and has been used in 7 African countries and 2 US states. Epi Info VHF enabled reporting of compatible data from multiple countries, contributing to international Ebola knowledge. However, challenges were encountered in accommodating the epidemic's unexpectedly large magnitude, addressing country-specific needs within 1 software product, and using the application in settings with limited Internet access and information technology support. Use of Epi Info VHF in the West Africa Ebola epidemic highlighted the fundamental importance of good data management for effective outbreak response, regardless of the software used. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  5. Astronaut Harrison Schmitt participates in simulation aboard KC-135

    Science.gov (United States)

    1972-01-01

    Scientist-Astronaut Harrison H. Schmitt, lunar module pilot of the Apollo 17 lunar landing mission, simulates preparing to deploy the Surface Electrical Properties Experiment during lunar surface extravehicular activity (EVA) simulation training under one-sixth gravity conditions aboard a U.S. Air Force KC-135 aircraft.

  6. Statistical characteristics of low-latitude ionospheric field-aligned irregularities obtained with the Piura VHF radar

    Directory of Open Access Journals (Sweden)

    J. L. Chau

    2002-08-01

    Full Text Available We present a summary of the statistical characteristics of echoes from ionospheric (E- and F-region field-aligned irregularities obtained with the Piura VHF radar. This radar is located at ~ 7.0° dip latitude, just outside the equatorial electrojet (EEJ region. Our results are based on (1 intermittent observations made between 1991 and 1999 just few days a year, and (2 continuous observations made between January 2000 and June 2001. During most of the intermittent observations, simultaneous measurements of EEJ and equatorial spread F (ESF irregularities were performed with the Jicamarca VHF radar. From the continuous measurements, we have obtained the diurnal and seasonal characteristics of a variety of parameters (percentage of occurrence, signal-to-noise ratio and/or Doppler velocities from the lower and upper E-region irregularities and also from F-region irregularities over Piura. For example, we have found that (1 the E-region echoes are stronger and occur more frequently during local summer (i.e. between December and March; (2 between May and June, the E-region echoes are weaker and occur less frequently; moreover, during these months, a semidiurnal wave with large amplitudes is observed in the meridional wind (> 100 ms- 1; (3 there is vertical wavelength of about 20 km in the Doppler velocity, particularly after midnight; (4 the lower (upper E-region Doppler velocities are influenced mainly by meridional winds (equatorial F-region vertical drifts. In addition, we have observed that the seasonal and daily occurrences of Piura F-region irregularities are similar to the occurrence of topside ESF irregularities over Jicamarca. The likelihood of occurrence of F-region irregularities over Piura and, therefore, topside ESF over Jicamarca is greater when there are no E-region irregularities over Piura. On the other hand, there is more probability of observing bottomtype/bottomside ESF irregularities over Jicamarca when E-region irregularities

  7. PMSE observations with the EISCAT VHF- and UHF-radars: Ice particles and their effect on ambient electron densities

    Science.gov (United States)

    Li, Qiang; Rapp, Markus

    2013-11-01

    It is now well understood that the occurrence of PMSE is closely connected to the presence of ice particles. These ice particles modify the ambient electron density by electron attachment which occasionally leads to large electron density depletions which have also been called ‘biteouts’. There has been some debate in the literature regarding the relative depth of such depletions which is usually expressed by the parameter Λ=|ZA|NA/ne. Here, |ZA|NA is the charge number density of ice particles and ne is the electron density. In this paper, we present, for the first time, the statistical distribution of Λ using measurements with the EISCAT VHF- and UHF-radars. Based on 25 h of simultaneous observations, we derived a total of 757 Λ values based on 15 min of data each. In each of these cases, PMSE were observed with the EISCAT VHF-radar but not with the UHF-radar and the UHF-measurement were hence used to determine the electron density profile. From these 757 cases, there are 699 cases with Λ⪡1, and only 33 cases with Λ>0.5 (21 cases with Λ>1). A correlation analysis of Λ versus PMSE volume reflectivities further reveals that there is no strong dependence between the two parameters. This is in accordance with current PMSE-theory based on turbulence in combination with a large Schmidt-number. The maxima of Λ from each profile show a negative relationship with the undisturbed electron densities deduced at the same altitudes. This reveals that the variability of Λ mainly depends on the variability of the electron densities. In addition, variations of aerosol number densities may also play a role. Although part of the observations were conducted during the HF heating experiments, the so-called overshoot effects did not significantly bias our statistical results. In order to avoid missing biteouts because of a superposition of coherent and incoherent scatter in the UHF-data, we finally calculated spectral parameters n by applying a simple fit to auto

  8. Low complexity MIMO receivers

    CERN Document Server

    Bai, Lin; Yu, Quan

    2014-01-01

    Multiple-input multiple-output (MIMO) systems can increase the spectral efficiency in wireless communications. However, the interference becomes the major drawback that leads to high computational complexity at both transmitter and receiver. In particular, the complexity of MIMO receivers can be prohibitively high. As an efficient mathematical tool to devise low complexity approaches that mitigate the interference in MIMO systems, lattice reduction (LR) has been widely studied and employed over the last decade. The co-authors of this book are world's leading experts on MIMO receivers, and here they share the key findings of their research over years. They detail a range of key techniques for receiver design as multiple transmitted and received signals are available. The authors first introduce the principle of signal detection and the LR in mathematical aspects. They then move on to discuss the use of LR in low complexity MIMO receiver design with respect to different aspects, including uncoded MIMO detection...

  9. Auxiliary VHF transmitter to aid recovery of solar Argos/GPS PTTs

    Science.gov (United States)

    Christopher P. Hansen; Mark A. Rumble; R. Scott Gamo; Joshua J. Millspaugh

    2014-01-01

    While conducting greater sage-grouse (Centrocercus urophasianus) research, we found that solar-powered global positioning systems platform transmitter terminals (GPS PTTs) can be lost if the solar panel does not receive adequate sunlight. Thus, we developed 5-g (mortality sensor included; Prototype A) and 9.8-g (no mortality sensor; Prototype B) auxiliary very high...

  10. Delphi Accounts Receivable Module -

    Data.gov (United States)

    Department of Transportation — Delphi accounts receivable module contains the following data elements, but are not limited to customer information, cash receipts, line of accounting details, bill...

  11. Comparison of wind measurements in the troposphere and mesosphere by VHF/MF radars and in-situ techniques

    Directory of Open Access Journals (Sweden)

    N. Engler

    2008-11-01

    Full Text Available Radar wind observations at frequencies between 1.98 and 53.5 MHz obtained at polar latitudes were compared to in-situ wind measurements by radiosondes at tropospheric altitudes and to winds from falling spheres at mesospheric altitudes. Comparisons are shown for several campaigns of radiosonde and falling sphere observations. The radar wind directions agree well to the radiosonde and falling sphere observations and are highly correlated. The winds estimated from radar measurements are less than the radiosonde data by about 15% for spaced antenna observations and by about 10% for the Doppler beam swinging experiment. At mesospheric altitudes the spaced antenna winds obtained from the wide-beam Andenes MF radar are underestimated in the order of 35% and winds from the narrow-beam Saura MF radar are underestimated by about 20% compared to falling sphere winds at altitudes between 70 and 80 km. Furthermore, the relation between wind measurements using narrow-beam and wide-beam antenna arrangements for the MF radars is discussed and VHF radar observations are compared to the wide-beam MF radar.

  12. Comparison of wind measurements in the troposphere and mesosphere by VHF/MF radars and in-situ techniques

    Science.gov (United States)

    Engler, N.; Singer, W.; Latteck, R.; Strelnikov, B.

    2008-11-01

    Radar wind observations at frequencies between 1.98 and 53.5 MHz obtained at polar latitudes were compared to in-situ wind measurements by radiosondes at tropospheric altitudes and to winds from falling spheres at mesospheric altitudes. Comparisons are shown for several campaigns of radiosonde and falling sphere observations. The radar wind directions agree well to the radiosonde and falling sphere observations and are highly correlated. The winds estimated from radar measurements are less than the radiosonde data by about 15% for spaced antenna observations and by about 10% for the Doppler beam swinging experiment. At mesospheric altitudes the spaced antenna winds obtained from the wide-beam Andenes MF radar are underestimated in the order of 35% and winds from the narrow-beam Saura MF radar are underestimated by about 20% compared to falling sphere winds at altitudes between 70 and 80 km. Furthermore, the relation between wind measurements using narrow-beam and wide-beam antenna arrangements for the MF radars is discussed and VHF radar observations are compared to the wide-beam MF radar.

  13. Observation of polar mesosphere summer echoes with calibrated VHF radars at 69° in the Northern and Southern hemispheres

    Science.gov (United States)

    Latteck, R.; Singer, W.; Morris, R. J.; Holdsworth, D. A.; Murphy, D. J.

    2007-07-01

    Polar Mesosphere Summer Echoes (PMSE) observed in the northern and southern hemisphere were studied using continuous measurements obtained by calibrated VHF radars located at Andenes (69.3°N) and Davis (68.6°S) during the boreal summer 2004 and the austral summer 2004/2005. The PMSE observed at Davis have a lower peak volume reflectivity of approximately 4 . 10-11 m-1 compared with their counterparts (7 . 10-10 m-1) observed at Andenes. The duration of the PMSE season is correlated with the dynamical and thermal state of the mesopause region supported by recent studies using meridional winds and temperatures. PMSE occurred less frequently but with greater variability above Davis. The diurnal variation of PMSE occurrence has a maximum around 11-16 LT in both hemispheres, and a minimum occurs during late evening with a longer duration in the southern hemisphere. The mean PMSE season at both sites started around 34 days before solstice, but the duration of the Davis PMSE season is about 9 days shorter than at Andenes. The maximum occurrence height of PMSE at Davis is 86 km which is about 1 km higher than at Andenes.

  14. Comparison of wind measurements in the troposphere and mesosphere by VHF/MF radars and in-situ techniques

    Energy Technology Data Exchange (ETDEWEB)

    Engler, N.; Singer, W.; Latteck, R.; Strelnikov, B. [Rostock Univ., Kuehlungsborn (Germany). Leibniz Inst. of Atmospheric Physics

    2008-07-01

    Radar wind observations at frequencies between 1.98 and 53.5 MHz obtained at polar latitudes were compared to in-situ wind measurements by radiosondes at tropospheric altitudes and to winds from falling spheres at mesospheric altitudes. Comparisons are shown for several campaigns of radiosonde and falling sphere observations. The radar wind directions agree well to the radiosonde and falling sphere observations and are highly correlated. The winds estimated from radar measurements are less than the radiosonde data by about 15% for spaced antenna observations and by about 10% for the Doppler beam swinging experiment. At mesospheric altitudes the spaced antenna winds obtained from the wide-beam Andenes MF radar are underestimated in the order of 35% and winds from the narrow-beam Saura MF radar are underestimated by about 20% compared to falling sphere winds at altitudes between 70 and 80 km. Furthermore, the relation between wind measurements using narrow-beam and wide-beam antenna arrangements for the MF radars is discussed and VHF radar observations are compared to the wide-beam MF radar. (orig.)

  15. Calculating the azimuth of mountain waves, using the effect of tilted fine-scale stable layers on VHF radar echoes

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    1999-02-01

    Full Text Available A simple method is described, based on standard VHF wind-profiler data, where imbalances of echo power between four off-vertical radar beams, caused by mountain waves, can be used to calculate the orientation of the wave pattern. It is shown that the mountain wave azimuth (direction of the horizontal component of the wavevector, is given by the vector [ W (PE - P W ,W (PN - P S ]; PN, PS, PE, PW are radar echo powers, measured in dB, in beams pointed away from vertical by the same angle towards north, south, east and west respectively, and W is the vertical wind velocity. The method is applied to Aberystwyth MST radar data, and the calculated wave vector usually, but not always, points into the low-level wind direction. The mean vertical wind at Aberystwyth, which may also be affected by tilted aspect-sensitive layers, is investigated briefly using the entire radar output 1990-1997. The mean vertical-wind profile is inconsistent with existing theories, but a new mountain-wave interpretation is proposed.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides; instruments and techniques.

  16. Effect of power on growth of nanocrystalline silicon films deposited by VHF PECVD technique for solar cell applications

    Science.gov (United States)

    Juneja, Sucheta; Verma, Payal; Savelyev, Dmitry A.; Khonina, Svetlana N.; Sudhakar, S.; Kumar, Sushil

    2016-04-01

    An investigation of the effect of power on the deposition of nanocrystalline silicon thin films were carried out using a gaseous mixture of silane and hydrogen in the 60MHz assisted VHF plasma enhanced chemical vapor deposition (PECVD) technique. The power was varied from 10 to 50 watt maintaining all other parameters constant. Corresponding layer properties w.r.t. material microstructure, optical, hydrogen content and electrical transport are studied in detail. The structural properties have been studied by Raman spectroscopy and x-ray diffraction (XRD). The presence of nano-sized crystals and their morphology have been investigated using atomic force microscopy (AFM). The role of bonded hydrogen content in the films have been studied from the results of Fourier transform infrared spectroscopy. It was observed from the results that with increase in power, crystalline volume fraction increases and crystallite size changes from 4 to 9 nm. The optical band gap varies from 1.7 to 2.1eV due to quantum confinement effect and which further can be explained with reduced hydrogen content. These striking features of nc-Si films can be used to fabricate stable thin film solar cells.

  17. Case study of stratospheric gravity waves of convective origin over Arctic Scandinavia. VHF radar observations and numerical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Rechou, A. [La Reunion Univ., St. Denis Messag, Ile de La Reunion (France). Lab. de l' Atmosphere et des Cyclones; Arnault, J.; Dalin, P.; Kirkwood, S. [Swedish Institute of Space Physics, Kiruna (Sweden)

    2013-03-01

    Orography is a well-known source of gravity and inertia-gravity waves in the atmosphere. Other sources, such as convection, are also known to be potentially important but the large amplitude of orographic waves over Scandinavia has generally precluded the possibility to study such other sources experimentally in this region. In order to better understand the origin of stratospheric gravity waves observed by the VHF radar ESRAD (Esrange MST radar) over Kiruna, in Arctic Sweden (67.88 N, 21.10 E), observations have been compared to simulations made using the Weather Research and Forecasting model (WRF) with and without the effects of orography and clouds. This case study concerns gravity waves observed from 00:00 UTC on 18 February to 12:00 UTC on 20 February 2007. We focus on the wave signatures in the static stability field and vertical wind deduced from the simulations and from the observations as these are the parameters which are provided by the observations with the best height coverage. As is common at this site, orographic gravity waves were produced over the Scandinavian mountains and observed by the radar. However, at the same time, southward propagation of fronts in the Barents Sea created short-period waves which propagated into the stratosphere and were transported, embedded in the cyclonic winds, over the radar site. (orig.)

  18. Digital controller for the Wave Propagation Laboratory's VHF and UHF wind-profiling radars

    Science.gov (United States)

    Moran, K.

    1984-09-01

    Principles are described for operation of a digital system that is used to control the operations of a multiple beam stratospheric-tropospheric (ST) radar system. The digital system, referred to as the radar controller, contains the digital logic for generating the necessary pulse sequences for modulation of the radar transmitter, gating the radar's receiver channels, and sequencing the antenna beams. The radar controller also performs digital-to-analog conversion and coherent averaging of the receiver necessary for signal detection in ST radars. The radar controller is controlled internally by a Z80 microprocessor, and the entire system functions as a peripheral device to a host minicomputer. Block diagrams and detailed circuit schematics for all the custom designed electronics are included.

  19. Low VHF Channel Measurements and Simulations in Indoor and Outdoor Scenarios

    Science.gov (United States)

    2015-05-01

    S11 and radiation pattern of the λ/6 antenna ......................8 Fig. 5 The USRP integrated on a PackBot mobile platform...comparison, whereas in Fig. 3a the signal is only received via an antenna. 3.1 System Hardware 3.1.1 Radio and Daughtercards We use the USRP model N210 SDR for...our tests.46 The USRP N210 provides an Ethernet interface that allows us to use software control for transmission and reception. The USRP is

  20. Exercise Aboard Attack Submarines: Rationale and New Options

    Science.gov (United States)

    2004-08-18

    experience loss of physical fitness while underway. Bennett and co-workers (2) noted a 7% reduction of maximal oxygen consumption in non-exercising...Inc. designed and built a comprehensive resistance exercise device to help counteract muscle deconditioning during long term space flights (the SX... Physical activity aboard nuclear submarines as measured by pedometry. Groton: Naval Submarine Medical Research Laboratory, Report 1053, 1985, p. 12

  1. Solar energy receiver

    Science.gov (United States)

    Schwartz, Jacob

    1978-01-01

    An improved long-life design for solar energy receivers provides for greatly reduced thermally induced stress and permits the utilization of less expensive heat exchanger materials while maintaining receiver efficiencies in excess of 85% without undue expenditure of energy to circulate the working fluid. In one embodiment, the flow index for the receiver is first set as close as practical to a value such that the Graetz number yields the optimal heat transfer coefficient per unit of pumping energy, in this case, 6. The convective index for the receiver is then set as closely as practical to two times the flow index so as to obtain optimal efficiency per unit mass of material.

  2. Receiver Gain Modulation Circuit

    Science.gov (United States)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  3. VHF SoOp (Signal of Opportunity) Technology Demonstration for Soil Moisture Measurement Using Microwave Hydraulic Boom Truck Platform

    Science.gov (United States)

    Joseph, A. T.; Deshpande, M.; O'Neill, P. E.; Miles, L.

    2017-01-01

    A goal of this research is to test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a global direct surface soil moisture (SM) and RZSM measurement system over a variety of land covers. Knowledge of RZSM up to a depth of 1 meter and surface SM up to a depth of 0.05 meter on a global scale, at a spatial resolution of 1-10 km through moderate-to-heavy vegetation, is critical to understanding global water resources and the vertical moisture gradient in the Earths surface layer which controls moisture interactions between the soil, vegetation, and atmosphere. Current observations of surface SM from space by L-band radiometers (1.4 GHz) and radars (1.26 GHz) are limited to measurements of surface SM up to a depth of 0.05 meter through moderate amounts of vegetation. This limitation is mainly due to the inability of L-band signals to penetrate through dense vegetation and deep into the soil column. Satellite observations of the surface moisture conditions are coupled to sophisticated models which extrapolate the surface SM into the root zone, thus providing an indirect estimate rather than a direct measurement of RZSM. To overcome this limitation, low-frequency airborne radars operating at 435 MHz and 118 MHz have been investigated, since these lower frequencies should penetrate denser vegetation and respond to conditions deeper in the soil.

  4. Spatial variability of the aspect sensitivity of VHF radar echoes in the troposphere and lower stratosphere during jet stream passages

    Directory of Open Access Journals (Sweden)

    J. G. Yoe

    Full Text Available The aspect sensitivity of SOUSY-VHF-radar oblique-beam echoes from the troposphere and lower stratosphere has been examined for a number of jet stream passages during the years 1990 - 1992. When the core of the jet is overhead or nearly so, vertical profiles of the aspect sensitivity display two notable features. First, the distinction between mainly isotropic and strongly aspect-sensitive echoes in the troposphere and the lower stratosphere, respectively, often reported for measurements made during calm conditions, does not necessarily prevail in the vicinity of the jet stream. Second, echoes obtained at altitudes near the height of the horizontal wind maximum are found to be more aspect sensitive for beams directed parallel to the horizontal flow or nearly so, than for other beam directions. It is demonstrated that time-averaged horizontal wind speeds estimated from the radar data, taking into account the reduced effective oblique-beam zenith angle resulting from aspect sensitivity, may exceed uncorrected wind speeds by as much as 10 m s-1 in these circumstances. Implications for wind profiling and for describing the backscattering process are discussed. Doppler spectral widths examined for one jet stream passage are found to be narrower in a beam aligned with the horizontal wind at heights near the wind speed maximum than corresponding widths measured in a beam projected at right angles to the jet. The narrowest spectra thus coincide with the most aspect-sensitive echoes, consistent with the hypothesis that such returns result from specular backscattering processes.

  5. Calculating the azimuth of mountain waves, using the effect of tilted fine-scale stable layers on VHF radar echoes

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    Full Text Available A simple method is described, based on standard VHF wind-profiler data, where imbalances of echo power between four off-vertical radar beams, caused by mountain waves, can be used to calculate the orientation of the wave pattern. It is shown that the mountain wave azimuth (direction of the horizontal component of the wavevector, is given by the vector [ W (PE - P W ,W (PN - P S ]; PN, PS, PE, PW are radar echo powers, measured in dB, in beams pointed away from vertical by the same angle towards north, south, east and west respectively, and W is the vertical wind velocity. The method is applied to Aberystwyth MST radar data, and the calculated wave vector usually, but not always, points into the low-level wind direction. The mean vertical wind at Aberystwyth, which may also be affected by tilted aspect-sensitive layers, is investigated briefly using the entire radar output 1990-1997. The mean vertical-wind profile is inconsistent with existing theories, but a new mountain-wave interpretation is proposed.

    Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides; instruments and techniques.

  6. Wideband CMOS receivers

    CERN Document Server

    Oliveira, Luis

    2015-01-01

    This book demonstrates how to design a wideband receiver operating in current mode, in which the noise and non-linearity are reduced, implemented in a low cost single chip, using standard CMOS technology.  The authors present a solution to remove the transimpedance amplifier (TIA) block and connect directly the mixer’s output to a passive second-order continuous-time Σ∆ analog to digital converter (ADC), which operates in current-mode. These techniques enable the reduction of area, power consumption, and cost in modern CMOS receivers.

  7. Biconical receiving antenna

    Science.gov (United States)

    Grimes, Dale M.

    1982-05-01

    The modal solution to a biconical receiving antenna with arbitrary arm angles and lengths is presented in the form of sums over special functions; sums which are exact in the sense that no electromagnetic approximations are made. The antenna load is confined within a sphere of small radius centered at the apices of the cones. The analytical formulation is presented, along with solutions for ψ very small and very large, and certain selected numerical data. The general solution permits calculation of all detailed fields near and far, both receiving and transmitting current modes on the antenna arms and caps and the power and the momentum absorbed by the antenna from an incoming plane wave. It is shown that the receiving current modes are necessary for electromagnetic momentum to be conserved during power reception. Detailed calculation of comparative receiving and transmitting admittances confirms that they are identical, as predicted by the reciprocity theorem. The radiation patterns, however, for retransmission during reception and for transmission differ.

  8. Help Seeking and Receiving.

    Science.gov (United States)

    Nadler, Arie

    Although social psychology has always had an interest in helping behavior, only recently has the full complexity of helping relations begun to be researched. Help seeking and receiving in the educational setting raise many issues regarding the use and effectiveness of the help itself. Central to all helping relations is the seeking/receiving…

  9. A meteor head echo analysis algorithm for the lower VHF band

    Directory of Open Access Journals (Sweden)

    J. Kero

    2012-04-01

    Full Text Available We have developed an automated analysis scheme for meteor head echo observations by the 46.5 MHz Middle and Upper atmosphere (MU radar near Shigaraki, Japan (34.85° N, 136.10° E. The analysis procedure computes meteoroid range, velocity and deceleration as functions of time with unprecedented accuracy and precision. This is crucial for estimations of meteoroid mass and orbital parameters as well as investigations of the meteoroid-atmosphere interaction processes. In this paper we present this analysis procedure in detail. The algorithms use a combination of single-pulse-Doppler, time-of-flight and pulse-to-pulse phase correlation measurements to determine the radial velocity to within a few tens of metres per second with 3.12 ms time resolution. Equivalently, the precision improvement is at least a factor of 20 compared to previous single-pulse measurements. Such a precision reveals that the deceleration increases significantly during the intense part of a meteoroid's ablation process in the atmosphere. From each received pulse, the target range is determined to within a few tens of meters, or the order of a few hundredths of the 900 m long range gates. This is achieved by transmitting a 13-bit Barker code oversampled by a factor of two at reception and using a novel range interpolation technique. The meteoroid velocity vector is determined from the estimated radial velocity by carefully taking the location of the meteor target and the angle from its trajectory to the radar beam into account. The latter is determined from target range and bore axis offset. We have identified and solved the signal processing issue giving rise to the peculiar signature in signal to noise ratio plots reported by Galindo et al. (2011, and show how to use the range interpolation technique to differentiate the effect of signal processing from physical processes.

  10. Autonomic function testing aboard the ISS using “PNEUMOCARD”

    Science.gov (United States)

    Baevsky, R. M.; Funtova, I. I.; Diedrich, A.; Chernikova, A. G.; Drescher, J.; Baranov, V. M.; Tank, J.

    2009-10-01

    Investigations of blood pressure, heart rate (HR), and heart rate variability (HRV) during long term space flights on board the "ISS" have shown characteristic changes of autonomic cardiovascular control. Therefore, alterations of the autonomic nervous system occurring during spaceflight may be responsible for in- and post-flight disturbances. The device "Pneumocard" was developed to further investigate autonomic cardiovascular and respiratory function aboard the ISS. The hard-software diagnostic complex "Pneumocard" was used during in-flight experiment aboard ISS for autonomic function testing. ECG, photoplethysmography, respiration, transthoracic bioimpedance and seismocardiography were assessed in one male cosmonaut (flight lengths six month). Recordings were made prior to the flight, late during flight, and post-flight during spontaneous respiration and controlled respiration at different rates. HR remained stable during flight. The values were comparable to supine measurements on earth. Respiratory frequency and blood pressure decreased during flight. Post flight HR and BP values increased compared to in-flight data exceeding pre-flight values. Cardiac time intervals did not change dramatically during flight. Pulse wave transit time decreased during flight. The maximum of the first time derivative of the impedance cardiogram, which is highly correlated with stroke volume was not reduced in-flight. Our results demonstrate that autonomic function testing aboard the ISS using "Pneumocard" is feasible and generates data of good quality. Despite the decrease in BP, pulse wave transit time was found reduced in space as shown earlier. However, cardiac output did not decrease profoundly in the investigated cosmonaut. Autonomic testing during space flight detects individual changes in cardiovascular control and may add important information to standard medical control. The recent plans to support a flight to Mars, makes these kinds of observations all the more relevant

  11. Ovarian Tumor Cells Studied Aboard the International Space Station (ISS)

    Science.gov (United States)

    2001-01-01

    In August 2001, principal investigator Jeanne Becker sent human ovarian tumor cells to the International Space Station (ISS) aboard the STS-105 mission. The tumor cells were cultured in microgravity for a 14 day growth period and were analyzed for changes in the rate of cell growth and synthesis of associated proteins. In addition, they were evaluated for the expression of several proteins that are the products of oncogenes, which cause the transformation of normal cells into cancer cells. This photo, which was taken by astronaut Frank Culbertson who conducted the experiment for Dr. Becker, shows two cell culture bags containing LN1 ovarian carcinoma cell cultures.

  12. SISTEMA WEB DE GEOLOCALIZACIÓN Y MONITOREO DE LA TORTUGA PODOCNEMIS LEWYANA EN EL RÍO SINÚ, MEDIANTE EL USO DE ANTENAS VHF Y DISPOSITIVOS GPS

    Directory of Open Access Journals (Sweden)

    Mario Macea Anaya

    2016-03-01

    Full Text Available Este trabajo tiene como finalidad el diseño e implementación de una aplicación para el monitoreo de las Tortugas de Río Podocnemis Lewyana, utilizando las tecnologías GPS (Global Positioning System y VHF (Very High Frequency. La aplicación permite apoyar los procesos de conservación y recuperación de la especie en el Departamento de Córdoba, en las poblaciones de Caño Viejo y Cotocá Arriba del municipio Santa Cruz de Lorica, Colombia. El uso de esa herramienta está dirigido a biólogos y personas de las comunidades rurales dedicadas a conservar dicha especie. En el desarrollo del proyecto se utilizaron 18 Tortugas de Río para su monitoreo. El resultado del trabajo es la aplicación Web Podocnemis-Soft. Su funcionamiento se basa en un dispositivo GPS y VHF, ubicado en una o varias de las tortugas Podocnemis Lewyana; los dispositivos envían los datos de la ubicación de la tortuga hasta un servidor para su procesamiento y posterior visualización de la información.

  13. Relationship between propagation direction of gravity waves in OH and OI airglow images and VHF radar echo occurrence during the SEEK-2 campaign

    Directory of Open Access Journals (Sweden)

    F. Onoma

    2005-10-01

    Full Text Available We report simultaneous observations of atmospheric gravity waves (AGW in OI (557.7nm and OH airglow images and VHF radar backscatter from field-aligned irregularities (FAI in the E-region during the SEEK-2 (Sporadic-E Experiment over Kyushu 2 campaign period from 29 July to 9 August 2002. An all-sky imager was operated at Nishino-Omote (30.5 N, 130.1 E, Japan. On 14 nights, 17 AGW events were detected in OI and OH airglow images. AGW propagated mostly toward the northeast or southeast. From comparison with the E-region FAI occurrence, which is detected by a nearby VHF radar (31.57MHz, we found that AGW tended to propagate southeastward during FAI events. This result suggests that the interaction between AGW and E-region plasma plays an important role in generating FAI. Furthermore, polarization electric fields generated directly by AGW may contribute to the FAI generation.

    Keywords. Atmospheric composition and structure (Airglow and aurora, Ionosphere (Ionospheric irregularities, Mid-latitude ionosphere

  14. Pressure difference receiving ears

    DEFF Research Database (Denmark)

    Michelsen, Axel; Larsen, Ole Næsbye

    2007-01-01

    waves behave in the air spaces leading to the interior surfaces of eardrums. A linear mathematical model with well-defined inputs is used for exploring how the directionality varies with the binaural directional cues and the amplitude and phase gain of the sound pathway to the inner surface...... of such pressure difference receiving ears have been hampered by lack of suitable experimental methods. In this review, we review the methods for collecting reliable data on the binaural directional cues at the eardrums, on how the eardrum vibrations depend on the direction of sound incidence, and on how sound...

  15. Angelopoulos receives Scarf Award

    Science.gov (United States)

    Lee, Martin

    AGU's third annual F.L. Scarf Award has been awarded to Vassilis Angelopoulos for his Ph.D. thesis, “Transport Phenomena in the Earth's Plasma Sheet,” which he completed at the University of California, Los Angeles, under the supervision of Charles Kennel. As part of the award, Angelopoulos will give an invited talk on a related topic at the upcoming AGU Fall Meeting in San Francisco.The award was established to honor Fred L. Scarf, a pioneer and leader in solar-planetary research. The award is given by the Space Physics and Aeronomy (SPA) section for outstanding dissertation research that contributes directly to solar-planetary science. The major criterion for the award is the impact or potential impact of the research on the field of solar-planetary studies. The awardee receives $1000 and is invited to deliver a paper at one of the following year's AGU meetings.

  16. 78 FR 14952 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Science.gov (United States)

    2013-03-08

    ... COMMISSION 47 CFR Part 2 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... of Earth Stations Aboard Aircraft (ESAA) in the 14.0-14.5 GHz band from secondary to primary and... stations of the FSS on a primary basis in the 11.7-12.2 GHz band (space-to-Earth), on an unprotected basis...

  17. CERN apprentice receives award

    CERN Multimedia

    2008-01-01

    Another CERN apprentice has received an award for the quality of his work. Stéphane Küng (centre), at the UIG ceremony last November, presided over by Geneva State Councillor Pierre-François Unger, Head of the Department of Economics and Health. Electronics technician Stéphane Küng was honoured in November by the Social Foundation of the Union Industrielle Genevoise (UIG) as one of Geneva’s eight best apprentices in the field of mechatronics. The 20-year-old Genevan obtained his Federal apprentice’s certificate (Certificat fédéral de capacité - CFC) in June 2007, achieving excellent marks in his written tests at the Centre d’Enseignement Professionnel Technique et Artisanal (CEPTA). Like more than 200 youngsters before him, Stéphane Küng spent part of his four-year sandwich course working at CERN, where he followed many practical training courses and gained valuable hands-on experience in various technical groups and labs. "It’ always very gr...

  18. An ambiguity-function-based method for analysis of Doppler decompressed radar signals applied to EISCAT measurements of oblique UHF-VHF meteor echoes

    Science.gov (United States)

    Wannberg, G.; Pellinen-Wannberg, A.; Westman, A.

    1996-05-01

    Binary phase modulation using Barker codes as the modulating sequences is often used as a pulse compression technique in incoherent scatter radar measurements of the ionospheric E region. Demodulation of the compressed signal is usually accomplished by matched filtering techniques. If the target has appreciable velocity, the resulting Doppler shift detunes the scattered signal relative to the filter, and the target response spreads over a large range interval. The paper describes the development of a new data analysis method, based on an ambiguity function description of radar total-power measurements, which uses the characteristic Doppler decompression signatures to identify, extract, and analyze high-velocity events from conventional Barker-coded power profile type incoherent scatter (IS) measurements. Data sets recorded with the European Incoherent Scatter UHF (931 MHz) and VHF (224 MHz) radars during the 1990-1991 Geminid and 1993 Perseid showers are shown to contain many events which are associated with individual meteors crossing the radar beams over a wide range of aspect angles, including a few near-radial cases. Line-of-sight velocities and effective cross sections are derived for some of the best dual radar events. The cross sections are very small and increase with decreasing wavelength, something not observed before. It is suggested that this is indicative of a scattering mechanism different from the one operating at near-normal incidence at VHF, and Rayleigh scatter from compact "balls" of plasma contained within the meteor coma is proposed as a possible candidate, in qualitative agreement with the observations. Finally, some signal-processing related aspects of the method are discussed. It is shown that most IS radars should be able to apply it to their existing programs with very little effort and without having to compromise the performance in normal E region applications. The method could therefore become a powerful tool for studies of meteor

  19. VHF and L-band scintillation characteristics over an Indian low latitude station, Waltair (17.7° N, 83.3° E

    Directory of Open Access Journals (Sweden)

    P. V. S. Rama Rao

    2005-10-01

    Full Text Available Characteristics of simultaneous VHF (244 MHz and L-band (1.5 GHz scintillations recorded at a low-latitude station, Waltair (17.7° N, 83.3° E, during the low sunspot activity year of March 2004 to March 2005, suggest that the occurrence of scintillations is mainly due to two types, namely the Plasma Bubble Induced (PBI, which maximizes during the post sunset hours of winter and equinoctial months, and the Bottom Side Sinusoidal (BSS type, which maximizes during the post-midnight hours of the summer solstice months. A detailed study on the spectral characteristics of the scintillations at both the frequencies show that the post-sunset scintillations are strong with fast fading (≈40 fad/min and are multiple in nature in scattering, giving rise to steep spectral slopes, whereas the post-midnight scintillations, which occur mostly on the VHF signal with low fading rate (≈4 fad/min, are of the BSS type, often showing typical Fresnel oscillations with reduced roll off spectral slopes, indicating that the type of irregularity resembles a thin screen structure giving rise to weak scattering. Using the onset times of several similar scintillation patches across the two satellite (FLEETSAT 73° E, INMARSAT 65° E ray paths (sub-ionospheric points are separated by 82 km, the East ward movement of the irregularity patches is found to vary from 150 to 250 m/s during the post sunset hours and decrease slowly during the post midnight hours. Further, the east-west extent of the PBI type of irregularities is found to vary from 100 to 500 km, while that of the BSS type extend up to a few thousand kilometers. Keywords. Ionosphere (Ionospheric irregularities; Auroral ionosphere; Electric fields and currents

  20. GNSS Software Receiver for UAVs

    DEFF Research Database (Denmark)

    Olesen, Daniel Madelung; Jakobsen, Jakob; von Benzon, Hans-Henrik

    2016-01-01

    This paper describes the current activities of GPS/GNSS Software receiver development at DTU Space. GNSS Software receivers have received a great deal of attention in the last two decades and numerous implementations have already been presented. DTU Space has just recently started development of ...... of our own GNSS software-receiver targeted for mini UAV applications, and we will in in this paper present our current progress and briefly discuss the benefits of Software Receivers in relation to our research interests....

  1. LEO degradation of graphite and carbon-based composites aboard Space Shuttle Flight STS-46

    Science.gov (United States)

    Spady, Blaine R.; Synowicki, R. A.; Hale, Jeffrey S.; Devries, M. J.; Woollam, John A.; Moore, Arthur W.; Lake, Max

    1995-01-01

    Six different types of carbon and carbon-boron nitride composites were exposed to low Earth orbit aboard Space Shuttle flight STS-46. The samples received a nominal atomic oxygen fluence of 2.2 x 10(exp 20) atoms/sq cm in 42 hours of exposure. Pyrolytic graphite and highly oriented pyrolytic graphite showed significant degradation, and the measured erosion yield was within a factor of two of published values. The erosion yield of pyrolytic boron nitride was found to be 2.6 x 10(exp 26) cu cm/atom in plasma asher exposure, over 42 times lower than that of pyrolytic graphite. This low erosion yield makes graphite plus boron nitride mixtures quite resistant to low Earth orbit exposure. Evidence suggests that the graphitic component was preferentially etched, leaving the surface boron nitride rich. Degradation resistance increases with boron nitride composition. Carbon fiber/carbon composites degraded in low Earth orbit, and the carbon pitch binder was found to etch more easily than the graphite fibers which have much higher degradation resistance.

  2. Low-altitude spaceborne GPS receiver for monitoring the ionosphere-magnetosphere interface region

    Science.gov (United States)

    Chiu, Y. T.; Schulz, M.; Schropp, D. R.; Rinaldi, M. A.

    The ionosphere-magnetosphere interface region (IMIR) is difficult to monitor in situ because processes occurring there have short dynamic time scales and long spatial scales. However, a system of spaceborne Global Positioning System (GPS) receivers with upward-looking antennas onboard LEO (low Earth orbit, altitude LEO and GPS orbit (altitude ~ 3 R_E). Phase and group delays between the two GPS signals transmitted through the IMIR are directly proportional to the total line-of-sight electron content, which is the remotely sensed parameter usually required for modeling. LEO spacecraft motion causes the line-of-sight to sweep through the IMIR so as to reveal information about the plasma-density structure. GPS receivers on TOPEX, the NASA/CNES ocean-monitoring satellite at altitude ~ 1430 km, have precisely this capability to monitor the IMIR. Moreover, the two-frequency VHF cross-ranging signals from GPS satellites can be used in the same manner as L-band signals to ``image'' the IMIR. We demonstrate this capability by applying our special deconvolution algorithm to some appropriate TOPEX/GPS data and thereby produce a dynamic display of density structure in the ionosphere-magnetosphere interface region.

  3. New Mobile Lidar Systems Aboard Ultra-Light Aircrafts

    Science.gov (United States)

    Chazette, Patrick; Shang, Xiaoxia; Totems, Julien; Marnas, Fabien; Sanak, Joseph

    2013-04-01

    Two lidar systems embedded on ultra light aircraft (ULA) flew over the Rhone valley, south-east of France, to characterize the vertical extend of pollution aerosols in this area influenced by large industrial sites. The main industrial source is the Etang de Berre (43°28' N, 5°01' E), close to Marseille city. The emissions are mainly due to metallurgy and petrochemical factories. Traffic related to Marseille's area contribute to pollution with its ~1500000 inhabitants. Note that the maritime traffic close to Marseille may play an important role due to its position as the leading French harbor . For the previous scientific purpose and for the first time on ULA, we flew a mini-N2 Raman lidar system to help the assessment of the aerosol optical properties. Another Ultra-Violet Rayleigh-Mie lidar has been integrated aboard a second ULA. The lidars are compact and eye safe instruments. They operate at the wavelength of 355 nm with a sampling along the line-of-sight of 0.75 m. Different flights plans were tested to use the two lidars in synergy. We will present the different approaches and discuss both their advantages and limitations. Acknowledgements: the lidar systems have been developed by CEA. They have been deployed with the support of FERRING France. We acknowledge the ULA pilots Franck Toussaint, François Bernard and José Coutet, and the Air Creation ULA Company for logistical help during the ULA campaign.

  4. 78 FR 14920 - Earth Stations Aboard Aircraft Communicating With Fixed-Satellite Service Geostationary-Orbit...

    Science.gov (United States)

    2013-03-08

    ... COMMISSION 47 CFR Parts 2 and 25 Earth Stations Aboard Aircraft Communicating With Fixed-Satellite Service... technical and licensing rules for Earth Stations Aboard Aircraft (ESAA), i.e., earth stations on aircraft...-11.2 GHz, 11.45-11.7 GHz, 11.7-12.2 GHz (space-to-Earth or downlink) and 14.0-14.5 GHz (Earth-to...

  5. Ionospheric tomography using the FORTE satellite

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, T.C.

    1993-08-01

    The possibility of obtaining ionospheric profile data via tomographic techniques has elicited considerable interest in recent years. The input data for the method is a set of total electron content measurements along intersecting lines of sight which form a grid. This can conveniently be provided by a fast-moving satellite with a VHF beacon which will generate the multiple paths needed for effective tomography. Los Alamos and Sandia National Laboratories will launch and operate the FORTE satellite for the US Department of Energy, with launch scheduled in 1995. FORTE will provide such a beacon. Additionally, wideband VHF receivers aboard the satellite will allow corraborative measurements of ionospheric profile parameters in some cases.

  6. Communications receivers principles and design

    CERN Document Server

    Rohde, Ulrich L; Zahnd, Hans

    2017-01-01

    This thoroughly updated guide offers comprehensive explanations of the science behind today’s radio receivers along with practical guidance on designing, constructing, and maintaining real-world communications systems. You will explore system planning, antennas and antenna coupling, amplifiers and gain control, filters, mixers, demodulation, digital communication, and the latest software defined radio (SDR) technology. Written by a team of telecommunication experts, Communications Receivers: Principles and Design, Fourth Edition, features technical illustrations, schematic diagrams, and detailed examples. Coverage includes: • Basic radio considerations • Radio receiver characteristics • Receiver system planning • Receiver implementation considerations • RF and baseband techniques for Software-Defined Radios • Transceiver SDR considerations • Antennas and antenna coupling • Mixers • Frequency sources and control • Ancillary receiver circuits • Performance measurement

  7. Forced Forward Smoldering Experiments Aboard The Space Shuttle

    Science.gov (United States)

    Fernandez-Pello, A. C.; Bar-Ilan, A.; Rein, G.; Urban, D. L.; Torero, J. L.

    2003-01-01

    Smoldering is a basic combustion problem that presents a fire risk because it is initiated at low temperatures and because the reaction can propagate slowly in the material interior and go undetected for long periods of time. It yields a higher conversion of fuel to toxic compounds than does flaming, and may undergo a transition to flaming. To date there have been a few minor incidents of overheated and charred cables and electrical components reported on Space Shuttle flights. With the establishment of the International Space Station, and the planning of a potential manned mission to Mars, there has been an increased interest in the study of smoldering in microgravity. The Microgravity Smoldering Combustion (MSC) experiment is part of a study of the smolder characteristics of porous combustible materials in a spacecraft environment. The aim of the experiment is to provide a better fundamental understanding of the controlling mechanisms of smoldering combustion under normal- and microgravity conditions. This in turn will aid in the prevention and control of smolder originated fires, both on earth and in spacecrafts. The microgravity smoldering experiments have to be conducted in a space-based facility because smoldering is a very slow process and consequently its study in a microgravity environment requires extended periods of time. The microgravity experiments reported here were conducted aboard the Space Shuttle. The most recent tests were conducted during the STS-105 and STS-108 missions. The results of the forward smolder experiments from these flights are reported here. In forward smolder, the reaction front propagates in the same direction as the oxidizer flow. The heat released by the heterogeneous oxidation reaction is transferred ahead of the reaction heating the unreacted fuel. The resulting increase of the virgin fuel temperature leads to the onset of the smolder reaction, and propagates through the fuel. The MSC data are compared with normal gravity

  8. Securities backed by healthcare receivables.

    Science.gov (United States)

    Pallarito, K

    1992-09-14

    Prudential Securities has placed $40 million in medium-term, taxable notes believed to be the first AAA-rated securities backed by healthcare receivables. Standard & Poor's Corp. rated the three-year notes, which were issued by NPF III, an Ohio company created to buy receivables from cash-strapped providers, and are backed by the Medicare, Medicaid and insurance receivables of 21 hospitals and healthcare providers nationwide.

  9. The variability of the occurrence of the Field Aligned Irregularities in the middle-latitude F region using the VHF radar observation at Daejon, South Korea.

    Science.gov (United States)

    Oh, S. J.; Kil, H.; Tae-yong, Y.; Kwak, Y. S.; Lee, W. K.

    2016-12-01

    The VHF radar observations at Daejeon in South Korea reveal the highly variable nature of the field-aligned irregularities (FAIs) in the middle-latitude F-region. Medium-scale travelling ionospheric disturbances (MSTIDs) are suggested as the source of FAIs, however, the occurrence climatology of the FAIs cannot be fully explained by the existence of the MSTIDs. Moreover, the occurrence climatology of the FAIs with respect to local time (pre-midnight and post-midnight) likely to have separate onset mechanisms. We investigate the role of the ionospheric disturbances(MSTIDs, Equatorial Plasma Bubbles(EPBs)) in the creation of the FAIs using the radar data at Daejon , the total electron content maps over Japan acquired during 2010-2015. and the measurements of the ion density by Swarm (2014,2015). We assess the causal linkage of the occurrence of the FAIs by examining the correlative occurrence of MSTIDs in middle latitude F-region and EPB in low latitude F-region.

  10. Giving receivables an 'outside' chance.

    Science.gov (United States)

    Slater, R M; Corti, R; Privitera, J

    1991-10-01

    Because of a greater number of patient visits and transactions, outpatient care typically involves more clerical and administrative work for less revenue than inpatient accounts. One hospital turned to outsourcing its outpatient receivables-contracting with an outside company to handle outpatient receivables. An outside company first can help an organization tackle an outpatient billing backlog and increase cash flow from outpatient accounts. Eventually, outsourcing can help an organization replace an outdated computer system and stem the tide of billing office employee attrition.

  11. Economic Galileo E5 Receiver

    Directory of Open Access Journals (Sweden)

    P. Kovar

    2012-04-01

    Full Text Available The Galileo system introduces an extremely wideband civil E5 signal for high precision navigation. The structure of the receiver for the E5 signal is complicated due to the signal complexity and the large bandwidth. It is possible to process the whole E5 signal or process separately E5a and E5b parts combining obtained results afterwards (we call here such method as piece-wise processing. The second procedure has three times worse standard deviation of the pseudorange then first one. The main goal of the paper is to present a design of an E5 receiver which we will call the economic E5 receiver (ecoE5. It is built from jointly controlled correlators for the processing of the E5a and E5b signals which are parts of the E5 signal. Control of these partial E5a and E5b correlators is realized by only one delay and one phase lock loops. The performance, i.e. the pseudorange noise and multipath errors, of the receiver equipped with the ecoE5, is only slightly worse (the standard deviation of the pseudorange noise is 10 - 20% larger than the performance of the optimal E5 receiver and it is much better than the performance of the receiver combining the piecewise (E5a and E5b measurements. The ecoE5 receiver hardware demands are about one quarter of the hardware demands of the classical E5 receiver.

  12. HIGH-EFFICIENCY INFRARED RECEIVER

    Directory of Open Access Journals (Sweden)

    A. K. Esman

    2016-01-01

    Full Text Available Recent research and development show promising use of high-performance solid-state receivers of the electromagnetic radiation. These receivers are based on the low-barrier Schottky diodes. The approach to the design of the receivers on the basis of delta-doped low-barrier Schottky diodes with beam leads without bias is especially actively developing because for uncooled receivers of the microwave radiation these diodes have virtually no competition. The purpose of this work is to improve the main parameters and characteristics that determine the practical relevance of the receivers of mid-infrared electromagnetic radiation at the operating room temperature by modifying the electrodes configuration of the diode and optimizing the distance between them. Proposed original design solution of the integrated receiver of mid-infrared radiation on the basis of the low-barrier Schottky diodes with beam leads allows to effectively adjust its main parameters and characteristics. Simulation of the electromagnetic characteristics of the proposed receiver by using the software package HFSS with the basic algorithm of a finite element method which implemented to calculate the behavior of electromagnetic fields on an arbitrary geometry with a predetermined material properties have shown that when the inner parts of the electrodes of the low-barrier Schottky diode is performed in the concentric elliptical convex-concave shape, it can be reduce the reflection losses to -57.75 dB and the standing wave ratio to 1.003 while increasing the directivity up to 23 at a wavelength of 6.09 μm. At this time, the rounded radii of the inner parts of the anode and cathode electrodes are equal 212 nm and 318 nm respectively and the gap setting between them is 106 nm. These parameters will improve the efficiency of the developed infrared optical-promising and electronic equipment for various purposes intended for work in the mid-infrared wavelength range. 

  13. Analog FM/FM versus digital color TV transmission aboard space station

    Science.gov (United States)

    Hart, M. M.

    1985-01-01

    Langley Research Center is developing an integrated fault tolerant network to support data, voice, and video communications aboard Space Station. The question of transmitting the video data via dedicated analog channels or converting it to the digital domain for consistancy with the test of the data is addressed. The recommendations in this paper are based on a comparison in the signal-to-noise ratio (SNR), the type of video processing required aboard Space Station, the applicability to Space Station, and how they integrate into the network.

  14. UWB communication receiver feedback loop

    Science.gov (United States)

    Spiridon, Alex; Benzel, Dave; Dowla, Farid U.; Nekoogar, Faranak; Rosenbury, Erwin T.

    2007-12-04

    A novel technique and structure that maximizes the extraction of information from reference pulses for UWB-TR receivers is introduced. The scheme efficiently processes an incoming signal to suppress different types of UWB as well as non-UWB interference prior to signal detection. Such a method and system adds a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. Moreover, sampling the second order statistical function such as, for example, the autocorrelation function (ACF) of the received signal and matching it to the ACF samples of the original pulses for each transmitted bit provides a more robust UWB communications method and system in the presence of channel distortions.

  15. GIVING AND RECEIVING CONSTRUCTIVE FEEDBACK

    Directory of Open Access Journals (Sweden)

    Ірина Олійник

    2015-05-01

    Full Text Available The article scrutinizes the notion of feedback applicable in classrooms where team teaching is provided. The experience of giving and receiving feedback has been a good practice in cooperation between a U.S. Peace Corps volunteer and a Ukrainian counterpart. Giving and receiving feedback is an effective means of classroom observation that provides better insight into the process of teaching a foreign language. The article discusses the stages of feedback and explicates the notion of sharing experience between two teachers working simultaneously in the same classroom. The guidelines for giving and receiving feedback have been provided as well as the most commonly used vocabulary items have been listed. It has been proved that mutual feedback leads to improving teaching methods and using various teaching styles and techniques.

  16. vhfRNAi: a web-platform for analysis of host genes involved in viral infections discovered by genome wide RNAi screens.

    Science.gov (United States)

    Thakur, Anamika; Qureshi, Abid; Kumar, Manoj

    2017-06-27

    Knockdown of host genes using high-throughput genome-wide RNA interference screens has identified numerous host factors that affect viral infections, which would be helpful in understanding host-virus interactions. We have developed a vhfRNAi web resource based on genome-wide RNAi experiments for viruses. It contains experimental details of 12 249 entries (host factors + restriction factors) for 18 viruses. Simultaneously, this resource encompasses analysis of overlapping genes, genome wide association studies, gene ontology (GO), pathogen interacting proteins, interaction networks and pathway enrichment. Using overlap analysis, it was found that Influenza A virus shared overlapping host genes with the majority of viruses including Hepatitis C virus and Dengue virus 2. In the genome wide association studies analysis, 429 diseases/traits were mapped, of which obesity-related traits were the most common. GO analysis revealed that the major categories belonged to metabolic processes, molecule transport, signal transduction, proteolysis, etc. In the pathogen interacting protein analysis, protein interaction data from different resources can be explored for further understanding of host-virus biology. By pathway enrichment analysis, a total of 8955 genes were mapped on 303 pathways with most of the hits coming from metabolic pathways. We have found 491 genes that are not essential for the host but essential for the virus and can be targeted to inhibit the virus. These may be explored as potential candidates for drug targets. The resource is freely accessible at and will be useful in understanding host-virus biology as well as identification of targets for the development of antiviral therapeutics.

  17. WHU VHF radar observations of the diurnal tide and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N, China

    Directory of Open Access Journals (Sweden)

    C. Huang

    2015-07-01

    Full Text Available The diurnal tide (DT and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N were studied based on the newly established Wuhan University (WHU VHF radar observations with the height intervals of 0.145 km (below 9 km and 0.58 km (above 9 km in the whole year of 2012. We find that the DT was the dominant tidal component and showed remarkable height and season variations. A prominent seasonally dependent height variability characteristic is that maximum DT amplitude usually occurs around 6 km in the winter and spring months, which might be due to the tidal wave energy concentration arising from the reflections from the strong eastward tropospheric jet around 13 km and the ground surface. Our results suggest that the background wind is a crucial cause for height variability and seasonal variability of DT. In April 2012, a notable strengthening of DT is observed. Meanwhile, the significant higher harmonics of tides, i.e., the semidiurnal, terdiurnal, and even quarterdiurnal tides, can also be observed, which has seldom been reported. Interestingly, these four tidal components displayed consistent short-term variability, implying that they were excited by the same dramatically varying tidal source. In addition, we identified two symptoms of the coupling of DT and planetary waves (PWs, which can also lead to the short-term DT variability. One is the sum and difference interactions between DT and PWs, causing the tidal amplitude short-term variability as a consequence of the energy exchange among the interacting waves. The other one is the modulation of DT by PWs, leading to that the amplitude of DT varies with the periods of the PWs.

  18. Heat flux and thermal conduction in O+ and H+ ion flows deduced from EISCAT-VHF radar observations in the high-latitude topside ionosphere

    Science.gov (United States)

    Wu, Jian; Taieb, Charley

    1994-06-01

    With two periods of EISCAT-VHF radar observations, magnetically quiet and moderately disturbed, we have calculated the H+ and O+ heat fluxes in using formulae of Wu and Taieb (1993), accounting not only for temperature gradients but also for pressure gradients, velocity gradients, and diffusion-thermal effects. They correspond to different physical processes that are calculated and compared between them. Then, the general features of the H+ and O+ ion thermal conductions are studied during the two periods of observation in the high-latitude topside ionosphere. The analysis of the two periods of measurements revealed the following trends, to be confirmed by further observations: (1) During the two periods the H+ heat flux Q2 is always upward in the altitude range from 600 km up to about 1000 km. It is larger during the quiet period than during the disturbed period. (2) The most important dominant mechanism for H+ heat flux is the diffusion-thermal effect due to the H+-O+ collision, with a correcting term due to the H+ temperature gradient. (3) The O+ heat flux is always downward in the same altitude range during the two periods of observations. The absolute value during the disturbed period is slightly larger than that during the quiet period. (4) The dominant mechanism for O+ heat flux is its temperature gradient, corrected by the coupling with the H+ ion. (5) The O+ thermal conduction is less important during the quiet period than during the disturbed period, while for the H+ thermal conduction it is the contrary. (6) The H+ thermal conduction increases with altitude below about 1000 km.

  19. Partitioning of a DRM receiver

    NARCIS (Netherlands)

    Wolkotte, P.T.; Smit, Gerardus Johannes Maria; Smit, L.T.

    In this article we present the results of partitioning the OFDM baseband processing of a DRM receiver into smaller independent processes. Furthermore, we give a short introduction into the relevant parts of the DRM standard. Based on the number of multiplications and additions we can map individual

  20. Madhu Sudan Receives Nevanlinna Prize

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 12. Madhu Sudan Receives Nevanlinna Prize. Meena Mahajan Priti Shankar. Research News Volume 7 Issue 12 December 2002 pp 84-90. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Books Received Information and Announcements ...

    Indian Academy of Sciences (India)

    committee receives about 120-150 problems from which it prepares a short-list of about. 30 problems taking care to see that all the areas-algebra, combinatorics, geometry and number theory - are represented. The most important single criterion for a problem to be short-listed is that it should be new and not have been ...

  2. Receiver Operating Characteristic (ROC) Analysis

    Science.gov (United States)

    Krupinski, Elizabeth A.

    2017-01-01

    Visual expertise covers a broad range of types of studies and methodologies. Many studies incorporate some measure(s) of observer performance or how well participants perform on a given task. Receiver Operating Characteristic (ROC) analysis is a method commonly used in signal detection tasks (i.e., those in which the observer must decide whether…

  3. Books Received Information and Announcements ...

    Indian Academy of Sciences (India)

    Books Received. Tradition, Science and Society. 5 Balachandra Roo. Navakarnataka. 1990, Rs.1S. A Textbook of Biology - Volume 2. P KG Nair, K P Achor, M J Hegde and 5 G Prabhu. Himalaya Publishing House. 1996, Rs.1S0. Indus Script - Its Nature and Structure. B V SUbbarayappa. New Era Publications. 1996 ...

  4. Keys to the Common Genera of Marine Plants Taken Aboard the Orange County Floating Marine Laboratory.

    Science.gov (United States)

    Williams, H. R.

    Provided is a dichotomous key to the common genera of marine algae and angiosperms which are taken aboard the Orange County Floating Marine Laboratory. It is designed primarily for use by junior and senior high school students. Drawings of representative members of the various genera are included. This work was prepared under an ESEA Title III…

  5. Living at Sea: Learning from Communal Life Aboard Sail Training Vessels

    Science.gov (United States)

    McCulloch, Ken

    2007-01-01

    This paper considers features of domestic and social life aboard sail training vessels, exploring the particular character of life at sea, and how these features contribute to the distinctive character of sail training experience as a context for learning. Methodologically, the study lies in the sociological tradition of ethnography, focusing on…

  6. Astronaut Edwin Aldrin undergoes zero-gravity training aboard KC-135

    Science.gov (United States)

    1969-01-01

    Astronaut Edwin E. Aldrin Jr., lunar module pilot of the Apollo 11 lunar landing mission, undergoes zero-gravity training aboard a U.S. Air Force KC-135 jet aircraft from nearby Patrick Air Force Base, Florida. Aldrin is wearing an Extravehicular Mobility Unit (EMU), the type of equipment which he will wear on the lunar surface.

  7. President Nixon welcomes the Apollo 11 astronauts aboard the U.S.S. Hornet

    Science.gov (United States)

    1969-01-01

    President Richard M. Nixon welcomes the Apollo 11 astronauts aboard the U.S.S. Hornet. Already confined to the Mobile Quarantine Facility are (left to right) Neil A. Armstrong, commander; Michael Collins, command module pilot; and Edwin E. Aldrin Jr., lunar module pilot.

  8. 78 FR 19172 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Science.gov (United States)

    2013-03-29

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 2 and 25 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... proposed rule that appeared in the Federal Register of March 8, 2013. The document proposed rules for Earth...

  9. 29 CFR 1918.65 - Mechanically powered vehicles used aboard vessels.

    Science.gov (United States)

    2010-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Cargo Handling Gear and Equipment Other Than Ship's Gear § 1918.65 Mechanically powered vehicles used aboard vessels. (a... operator's view, and openings in the top of the guard shall not exceed six inches (15.24 cm) in one of the...

  10. Soft X-ray Focusing Telescope Aboard AstroSat: Design ...

    Indian Academy of Sciences (India)

    K. P. Singh

    2017-06-19

    Jun 19, 2017 ... Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance. K. P. SINGH1,∗ ... Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational ..... products using the SXT pipeline software. The pipeline requires Level-1 data files and ...

  11. Analysis Methods for the Polarimetric WISDOM Radar aboard the ExoMars Rover

    Science.gov (United States)

    Plettemeier, D.; Benedix, W.-S.; Statz, C.; Lu, Y.; Herve, Y.; Le Gall, A.; Ciarletti, V.

    2017-09-01

    In this paper, we describe the capabilities of the fully polarimetric antenna system of the WISDOM GPR aboard the ExoMars rover in terms of a polarimetric data analysis as well as the setting and procedure for left-right-detection and entropy-based classification of (buried) objects.

  12. Investigation into noise exposure of engine room personnel aboard MS Trident Amsterdam

    NARCIS (Netherlands)

    Buiten, J.; Aartsen, H.

    1979-01-01

    The noise exposure in terms of equivalent continuous sound level Leq of engine room personnel was determined aboard the freighter m.s. "Trident Amsterdam" during ordinary trade voyages by means of two methods: the first by making use of dosimeters, the second by measuring the sound levels in the

  13. Soft X-ray Focusing Telescope Aboard AstroSat: Design ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy; Volume 38; Issue 2. Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance. K. P. Singh G. C. Stewart N. J. Westergaard S. Bhattacharayya S. Chandra V. R. Chitnis G. C. Dewangan A. T. Kothare I. M. Mirza K. Mukerjee V. Navalkar ...

  14. All Aboard the "Titanic": Character Journals Are Just the Tip of the Iceberg.

    Science.gov (United States)

    Mercurio, Mia Lynn

    1999-01-01

    Describes how a 7th-grade reading class used character journals to explore the sailing and the sinking of the "Titanic." Describes how the students took ownership of their research and enjoyed reading and writing about actual events as they became a passenger or crew member aboard the "Titanic," explored the ship, experienced…

  15. Development of a passive VHF radar system using software-defined radio for equatorial plasma instability studies

    Science.gov (United States)

    Tuysuz, B.; Urbina, J.; Lind, F. D.

    2013-07-01

    In this paper, a bistatic passive radar receiver system named "Coherent-scatter Atmospheric Passive Radar Imager (CAPRI)" is described. It is primarily designed to study the dynamics of the upper atmosphere by utilizing "transmitters of opportunity" as the RF target illuminators. CAPRI is constructed using the open source software-defined radio toolkit, GNU Radio, to meet the signal processing requirements in combination with the open source hardware, Universal Software Radio Peripheral 2, for data acquisition. The resultant system is highly flexible, and we present the details of the design as well as a performance analysis. CAPRI will be deployed in Peru, near the magnetic equator, for long-term operations in the area. FM stations near Lima, Peru, will be utilized with the targets of interest being the equatorial electrojet and the spread F. The results will then be compared to the Jicamarca Unattended Long-term investigations of the Ionosphere and Atmosphere (JULIA) radar data, and CAPRI will be used to improve the simultaneous time and spatial coverage in the region in a more cost-effective manner.

  16. Stability of Dosage Forms in the Pharmaceutical Payload Aboard Space Missions

    Science.gov (United States)

    Du, Brian J.; Daniels, Vernie; Boyd, Jason L.; Crady, Camille; Satterfield, Rick; Younker, Diane R.; Putcha, Lakshmi

    2009-01-01

    Efficacious pharmaceuticals with adequate shelf lives are essential for successful space medical operations. Stability of pharmaceuticals, therefore, is of paramount importance for assuring the health and wellness of astronauts on future space exploration missions. Unique physical and environmental factors of space missions may contribute to the instability of pharmaceuticals, e.g., radiation, humidity and temperature variations. Degradation of pharmaceutical formulations can result in inadequate efficacy and/or untoward toxic effects, which could compromise astronaut safety and health. Methods: Four identical pharmaceutical payload kits containing 31 medications in different dosage forms (liquid, tablet, capsule, ointment and suppository) were transported to the International Space Station aboard the Space Shuttle (STS-121). One of the 4 kits was stored on the Shuttle and the other 3 were stored on the International Space Station (ISS) for return to Earth at 6-month interval aboard a pre-designated Shuttle flight for each kit. The kit stored on the Shuttle was returned to Earth aboard STS-121 and 2 kits from ISS were returned on STS 117 and STS-122. Results: Analysis of standard physical and chemical parameters of degradation was completed for pharmaceuticals returned by STS-121 after14 days, STS - 117 after11 months and STS 122 after 19 months storage aboard ISS. Analysis of all flight samples along with ground-based matching controls was completed and results were compiled. Conclusion: Evaluation of results from the shuttle (1) and ISS increments (2) indicate that the number of formulations degraded in space increased with duration of storage in space and was higher in space compared to their ground-based counterparts. Rate of degradation for some of the formulations tested was faster in space than on Earth. Additionally, some of the formulations included in the medical kits were unstable, more so in space than on the ground. These results indicate that the

  17. Scintillation-Hardened GPS Receiver

    Science.gov (United States)

    Stephens, Donald R.

    2015-01-01

    CommLargo, Inc., has developed a scintillation-hardened Global Positioning System (GPS) receiver that improves reliability for low-orbit missions and complies with NASA's Space Telecommunications Radio System (STRS) architecture standards. A software-defined radio (SDR) implementation allows a single hardware element to function as either a conventional radio or as a GPS receiver, providing backup and redundancy for platforms such as the International Space Station (ISS) and high-value remote sensing platforms. The innovation's flexible SDR implementation reduces cost, weight, and power requirements. Scintillation hardening improves mission reliability and variability. In Phase I, CommLargo refactored an open-source GPS software package with Kalman filter-based tracking loops to improve performance during scintillation and also demonstrated improved navigation during a geomagnetic storm. In Phase II, the company generated a new field-programmable gate array (FPGA)-based GPS waveform to demonstrate on NASA's Space Communication and Navigation (SCaN) test bed.

  18. Femtosecond Photon-Counting Receiver

    Science.gov (United States)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-01-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time/pulse-width measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  19. Digital-data receiver synchronization

    Science.gov (United States)

    Smith, Stephen F.; Turner, Gary W.

    2005-08-02

    Digital-data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  20. Diversity of MMSE MIMO Receivers

    CERN Document Server

    Mehana, Ahmed Hesham

    2011-01-01

    In most MIMO systems, the family of waterfall error curves, calculated at different spectral efficiencies, are asymptotically parallel at high SNR. In other words, most MIMO systems exhibit a single diversity value for all {\\em fixed} rates. The MIMO MMSE receiver does not follow this pattern and exhibits a varying diversity in its family of error curves. This effect cannot be captured by DMT analysis, due to the fact that all fixed rates correspond to the same multiplexing gain, thus they cannot be differentiated within DMT analysis. This work analyzes this interesting behavior of the MMSE MIMO receiver and produces the MMSE MIMO diversity at each rate. The diversity of the quasi-static flat-fading MIMO channel consisting of any arbitrary number of transmit and receive antennas is fully characterized, showing that full spatial diversity is possible for all antenna configurations if and only if the rate is within a certain bound which is a function of the number of antennas. For other rate brackets, the avail...

  1. Absorption Efficiency of Receiving Antennas

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Frandsen, Aksel

    2005-01-01

    A receiving antenna with a matched load will always scatter some power. This paper sets an upper and a lower bound on the absorption efficiency (absorbed power over sum of absorbed and scattered powers), which lies between 0 and 100% depending on the directivities of the antenna and scatter...... patterns. It can approach 100% as closely as desired, although in practice this may not be an attractive solution. An example with a small endfire array of dipoles shows an efficiency of 93%. Several examples of small conical horn antennas are also given, and they all have absorption efficiencies less than...

  2. Broadband direct RF digitization receivers

    CERN Document Server

    Jamin, Olivier

    2014-01-01

    This book discusses the trade-offs involved in designing direct RF digitization receivers for the radio frequency and digital signal processing domains.  A system-level framework is developed, quantifying the relevant impairments of the signal processing chain, through a comprehensive system-level analysis.  Special focus is given to noise analysis (thermal noise, quantization noise, saturation noise, signal-dependent noise), broadband non-linear distortion analysis, including the impact of the sampling strategy (low-pass, band-pass), analysis of time-interleaved ADC channel mismatches, sampling clock purity and digital channel selection. The system-level framework described is applied to the design of a cable multi-channel RF direct digitization receiver. An optimum RF signal conditioning, and some algorithms (automatic gain control loop, RF front-end amplitude equalization control loop) are used to relax the requirements of a 2.7GHz 11-bit ADC. A two-chip implementation is presented, using BiCMOS and 65nm...

  3. CERN physicist receives Einstein Medal

    CERN Multimedia

    2006-01-01

    On 29 June the CERN theorist Gabriele Veneziano was awarded the prestigious Albert Einstein Medal for significant contributions to the understanding of string theory. This award is given by the Albert Einstein Society in Bern to individuals whose scientific contributions relate to the work of Einstein. Former recipients include exceptional physicists such as Murray Gell-Mann last year, but also Stephen Hawking and Victor Weisskopf. Gabriele Veneziano, a member of the integrated CERN Theory Team since 1977, led the Theory Division from 1994 to 1997 and has already received many prestigious prizes for his outstanding work, including the Enrico Fermi Prize (see CERN Courier, November 2005), the Dannie Heineman Prize for mathematical physics of the American Physical Society in 2004 (see Bulletin No. 47/2003), and the I. Ya. Pomeranchuk Prize of the Institute of Theoretical and Experimental Physics (Moscow) in 1999.

  4. Swimming classroom. Environmental education aboard a solar powered boat; Schwimmendes Klassenzimmer. Umweltbildungsangebote an Bord einer Solarfaehre

    Energy Technology Data Exchange (ETDEWEB)

    Moerk, M. [Bodensee-Stiftung, Radolfzell (Germany)

    2006-07-01

    Summary: The swimming classroom is a particular environmental education programme. Since 2002 school classes are taught aboard the solar ferry Helio at the Lower Lake Constance. Schoolboys and girls as well as teachers have the opportunity to enlarge their knowledge about Lake Constance, its natural environment and the solar ferry Helio. They also get informed about photovoltaic systems, water pollution control and environment-friendly tourism in the Lake Constance region. Solar ferry is most suitable for nature and adventure pedagogy as well as experimental instruction. School classes and advanced training groups can easily carry out a comprehensive programme aboard the Helio and experience nature and solar technology cruising on the lake. Issues are - Energy/Photovoltaic - Limnology - Life in and on the water - Water pollution control - Geography/Landscape development. (orig.)

  5. Apollo 12 crew welcomed aboard U.S.S. Hornet by Rear Admiral Donald David

    Science.gov (United States)

    1969-01-01

    Rear Admiral Donald C. David, Commander, Manned Spacecraft Recovery Force, Pacific, welcomes the crew of the Apollo 12 lunar landing mission aboard the U.S.S. Hornet, prime recovery vessel for the mission. A color guard was also on hand for the welcoming ceremonies. Inside the Mobile Quarantine Facility are (left to right) Astronauts Charles Conrad Jr., commander; Richard F. Gordon Jr., command module pilot; and Alan L. Bean, lunar module pilot.

  6. The Close Aboard Bastion: a Soviet ballistic missile submarine deployment strategy

    OpenAIRE

    Kreitler, Walter M

    1988-01-01

    Approved for public release; distribution is unlimited This thesis describes and analyzes a possible deployment posture for the Soviet ballistic missile submarine force. It examines the proposition that the Soviet Navy will establish a point defense, labeled "Close Aboard Bastions" (CABs), for its ballistic missile submarine fleet within the Soviet claimed 12 nautical mile territorial sea. This is a logical derivation of the currently widely held view that the Soviets will estab...

  7. Management of demand based inventory aboard submarine tenders servicing attack (SSN) submarines

    OpenAIRE

    Ross, Timothy Joseph

    1990-01-01

    Approved for public release; distribution is unlimited. This thesis examines the computation of inventory levels based on demand history aboard Submarine Tenders that use the Shipboard Automated Data Processing System (SUADPS) for inventory control. The focus of the thesis was the workload and supply effectiveness issues associated with the processing of the SUADPS levels setting program. The objective of the thesis was to determine the effect on supply effectiveness and stock churn if the...

  8. Design and Performance of the WISDOM Antenna System aboard the ExoMars Rover

    Science.gov (United States)

    Plettemeier, D.; Ciarletti, V.; Hamran, S.; Corbel, C.; Linke, S.; Benedix, W.

    2009-04-01

    A full polarimetric antenna system on board the ExoMars rover is part of the Experiment "Water Ice and Subsurface Deposit Observations on Mars" (WISDOM). The WISDOM-Experiment is a Ground Penetrating Radar (GPR) selected to be part of the Pasteur payload aboard the rover of the ExoMars mission. The Pasteur Panoramic Instruments (wide angle camera PANCAM, infrared spectrometer MIMA and WISDOM) will perform large-scale scientific investigations at the sites the Rover will visit. Among these instruments, WISDOM is the only one that can provide a view of the subsurface structure prior to drilling. WISDOM is the first space borne GPR aboard a rover and has been designed to characterize the shallow subsurface structure of Mars. WISDOM will give for the first time access to the geological structure, electromagnetic nature, and, possibly, of hydrological state of the shallow subsurface by retrieving the layering and properties of the buried reflectors. It will address some important related science questions regarding the planet present state and past evolution. The measured data will also be used to determine the most promising locations at which to obtain underground samples with the drilling system mounted on board the rover. The instrument objective for WISDOM is to get high-resolution measurements down to 2-meters depth in the Martian crust. The radar is a gated step frequency system covering the frequency range from 500 MHz to 3 GHz. The radar is fully polarimetric and makes use of four ultra wideband Vivaldi antennas. This poster describes the requirements, the design and the realization of the WISDOM antenna system accommodated on the ExoMars rover. Simulated antenna performance and measured antenna parameters as well as preliminary antenna test measurements performed in the lab and in permafrost regions on earth will be discussed in this poster presentation. The main design requirements of the WISDOM antenna system are driven one hand by the required science

  9. 78 FR 64596 - Celerity Partners IV, LLC, Celerity AHI Holdings SPV, LLC, and All Aboard America! Holdings, Inc...

    Science.gov (United States)

    2013-10-29

    ... Transportation Board, DOT. ACTION: Notice tentatively authorizing finance transaction. SUMMARY: All Aboard... either the quality of the human environment or the conservation of energy resources. It is ordered: 1...

  10. Development of wide band digital receiver for atmospheric radars using COTS board based SDR

    Science.gov (United States)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Digital receiver extracts the received echo signal information, and is a potential subsystem for atmospheric radar, also referred to as wind profiling radar (WPR), which provides the vertical profiles of 3-dimensional wind vector in the atmosphere. This paper presents the development of digital receiver using COTS board based Software Defined Radio technique, which can be used for atmospheric radars. The developmental work is being carried out at National Atmospheric Research Laboratory (NARL), Gadanki. The digital receiver consists of a commercially available software defined radio (SDR) board called as universal software radio peripheral B210 (USRP B210) and a personal computer. USRP B210 operates over a wider frequency range from 70 MHz to 6 GHz and hence can be used for variety of radars like Doppler weather radars operating in S/C bands, in addition to wind profiling radars operating in VHF, UHF and L bands. Due to the flexibility and re-configurability of SDR, where the component functionalities are implemented in software, it is easy to modify the software to receive the echoes and process them as per the requirement suitable for the type of the radar intended. Hence, USRP B210 board along with the computer forms a versatile digital receiver from 70 MHz to 6 GHz. It has an inbuilt direct conversion transceiver with two transmit and two receive channels, which can be operated in fully coherent 2x2 MIMO fashion and thus it can be used as a two channel receiver. Multiple USRP B210 boards can be synchronized using the pulse per second (PPS) input provided on the board, to configure multi-channel digital receiver system. RF gain of the transceiver can be varied from 0 to 70 dB. The board can be controlled from the computer via USB 3.0 interface through USRP hardware driver (UHD), which is an open source cross platform driver. The USRP B210 board is connected to the personal computer through USB 3.0. Reference (10 MHz) clock signal from the radar master oscillator

  11. High bit rate BPSK receiver

    Science.gov (United States)

    Osorio-Marti, J. A.; Sieiro, J. J.; Lopez-Villegas, J. M.

    2005-06-01

    This work presents a simple differentially BPSK receiver front-end using a novel schema without the need of an explicit carrier recovery system. The main principle of operation is the conversion of the incoming BPSK signal into an ASK signal having the same modulation pattern. Two versions of the system have been designed. One is intended to work at the 433.92 MHz ISM band and the other at 2 GHz frequency band. Accordingly, two prototypes of the system core, the BPSK to ASK converter circuit, have been implemented and tested. First a hybrid version for the low frequency operation and, second a multi chip module (MCM) for the 2 GHz frequency band. The system performance has been evaluated using Agilent Technologies Advanced Design System (ADS) platform. The ability to jointly perform system, circuit and EM simulations and co-simulations is the main advantage of this design tool. Obtained results indicate that modulation rates up to 20 Mbits/s for the hybrid version and up to 80 Mbits/s for the MCM version can be reached.

  12. Sistema de adquisición de datos para la medición de parámetros radioeléctricos en antenas lineales en la banda de TV de VHF y UHF System of acquisition of information for measurement of radioelectric parameters in linear antennas in the band of VHF and UHF’s television

    Directory of Open Access Journals (Sweden)

    María del Pilar Celemín

    2007-06-01

    Full Text Available Este proyecto desarrolla un sistema de adquisición y procesamiento de datos para la medición y ajuste de parámetros radioeléctricos de antenas lineales en las bandas de VHF y UHF. Como señal de prueba se utilizan algunas de las señales de televisión que se encuentran en el espectro radioeléctrico, provenientes de los transmisores que radian señales de canales nacionales. El receptor implementado incluye un sintonizador comercial de televisión que toma como muestra la señal portadora de video. Esta señal es amplificada, filtrada, almacenada y acondicionada, para ser leída por el puerto serial de un computador personal y procesada empleando un programa en Visual Basic, con una interfaz gráfica que permite una interacción amigable con el usuario. Desde acá se interactúa con un microcontrolador que controla el mecanismo de posicionamiento de la antena receptora por medio de una estructura electromecánica, que le permite ejecutar movimientos en dos grados de libertad: en azimut y en elevación. Con esto se logra un sistema capaz de determinar automáticamente el apuntamiento óptimo de la antena de acuerdo al máximo nivel de recepción de señal. Así mismo, se determinan parámetros propios de la antena tales como: el patrón de radiación (tanto en el plano horizontal como vertical, la ganancia directiva de la antena, la ganancia en cada uno de los puntos que conforman el plano principal, y otros parámetros de interés para el análisis de las características reales de antenas lineales.This project develops a data acquisition and processing system for measuring and adjusting lineal-antenna radioelectric parameters in VHF and UHF. Television signals are used as test signal. They can be found in radio electric spectrum, as they come from commercial transmitters that broadcast signals of national channels. The achieved receptor includes a television commercial tuner for obtaining video signal. Later, this signal is conditioning to

  13. Ionospheric plasma by VHF waves

    Indian Academy of Sciences (India)

    ... chart recorder at Varanasi during 1991 to 1999. The amplitude fluctuations having peak to peak variations>1 dB have been con- sidered for the present analysis. At Varanasi scintillations are frequently observed during nighttime, hence only nocturnal variation of irregularities in different months and sea- sons are studied.

  14. Microwave receivers with electronic warfare applications

    CERN Document Server

    Tsui, James

    2005-01-01

    This book by the author of Digital Techniques for Wideband Receivers willbe like no other one on your book shelf as the definitive word on electronicwarfare (EW) receiver design and performance. Whether you are an EWscientist involved in the test and evaluation of EW receivers or a designerof RWR's and other EW-related receivers, Microwave Receivers withElectronic Warfare Applications is a handy reference through which you canperfect your technical art. Lucidly written, this book is a treatise on EWreceivers that is relevant to you if you are just looking for a top-levelinsight into EW receive

  15. 'Sea legs': sharpened Romberg test after three days on a live-aboard dive boat.

    Science.gov (United States)

    Gibbs, Clinton R; Commons, Katherine H; Brown, Lawrence H; Blake, Denise F

    2010-12-01

    The sharpened Romberg test (SRT) is commonly used by diving and hyperbaric physicians as an indicator of neurological decompression illness (DCI). People who spend a prolonged time on a boat at sea experience impairment in their balance on returning to shore, a condition known as mal de debarquement ('sea legs'). This conditioning of the vestibular system to the rocking motion of a boat at sea may impact on the utility of the SRT in assessing a diver with potential DCI after a live-aboard dive trip. To assess the impact 'sea legs' has on the SRT after three days on a live-aboard dive trip. Thirty-nine staff and passengers of a three-day, live-aboard dive trip performed a SRT before and after their journey, with assessment of potential variables, including middle ear barotrauma, alcohol consumption, sea-sickness and occult DCI. There was no statistically significant impact on SRT performance, with 100% completion pre-trip and 35 out of 36 divers (97.2%) post-trip. There were trends towards more attempts being required and time needed for successful SRT post-trip, but these were not statistically significant. There was a small, but noteworthy incidence of middle-ear barotrauma, with seven people affected pre-trip, and 13 post-trip. There was a higher incidence in student divers. Middle-ear barotrauma did not appear to have a direct impact on SRT performance. There was no significant impact on SRT performance resulting from 'sea legs' after three days at sea. Recreational divers, especially dive students, have a substantial incidence of mild middle ear barotrauma.

  16. Commercial opportunities in bioseparations and physiological testing aboard Space Station Freedom

    Science.gov (United States)

    Hymer, W. C.

    1992-01-01

    The Center for Cell Research (CCR) is a NASA Center for the Commercial Development of Space which has as its main goal encouraging industry-driven biomedical/biotechnology space projects. Space Station Freedom (SSF) will provide long duration, crew-tended microgravity environments which will enhance the opportunities for commercial biomedical/biotechnology projects in bioseparations and physiological testing. The CCR bioseparations program, known as USCEPS (for United States Commercial Electrophoresis Program in Space), is developing access for American industry to continuous-flow electrophoresis aboard SSF. In space, considerable scale-up of continuous free-flow electrophoresis is possible for cells, sub cellular particles, proteins, growth factors, and other biological products. The lack of sedemination and buoyancy-driven convection flow enhances purity of separations and the amount of material processed/time. Through the CCR's physiological testing program, commercial organizations will have access aboard SSF to physiological systems experiments (PSE's); the Penn State Biomodule; and telemicroscopy. Physiological systems experiments involve the use of live animals for pharmaceutical product testing and discovery research. The Penn State Biomodule is a computer-controlled mini lab useful for projects involving live cells or tissues and macro molecular assembly studies, including protein crystallization. Telemicroscopy will enable staff on Earth to manipulate and monitor microscopic specimens on SSF for product development and discovery research or for medical diagnosis of astronaut health problems. Space-based product processing, testing, development, and discovery research using USCEPS and CCR's physiological testing program offer new routes to improved health on Earth. Direct crew involvement-in biomedical/biotechnology projects aboard SSF will enable better experimental outcomes. The current data base shows that there is reason for considerable optimism

  17. All aboard!

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    Every year, CERN's surveyors take detailed measurements to check the alignment of the LHC components. This year, from 16 to 18 January, they took some of those measurements for the first time using a brand-new remotely controlled train in one of the long straight sections.   From left to right: Thierry Feniet, Patrick Bestmann and Cédric Charrondière in the arms of the measuring wagon. This train doesn’t take people, it takes pictures. Its purpose? To save CERN’s surveyors from having to take the alignment measurements manually, particularly in areas where operators are subject to constraints due to radioactivity (in line with the ALARA principle of keeping radiation exposure to a level that is “as low as reasonably achievable”). The surveyors’ train, over four years in development, is the joint brain-child of several groups from the EN and BE Departments. The result is a state-of-the-art device which, as Thierr...

  18. Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance

    DEFF Research Database (Denmark)

    Singh, K; Stewart, G.; Westergaard, Niels Jørgen Stenfeldt

    2017-01-01

    medium resolution X-ray spectroscopy of cosmic X-ray sources of various types. It is the most sensitive X-ray instrument aboard the AstroSat. In its first year of operation, SXT has been used to observe objects ranging from active stars, compact binaries, supernova remnants, active galactic nuclei...... and clusters of galaxies in order to study its performance and quantify its characteriztics. Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational constraints, pipeline processing and its in-orbit performance based on preliminary results from its...

  19. Trough Receiver Heat Loss Testing (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowski, A.; Feik, C.; Hansen, R.; Phillips, S.; Bingham, C.; Netter, J.; Forristal, R.; Burkholder, F.; Meglan, B.; Wolfrum, E.

    2006-02-01

    This presentation describes the design, fabrication, and qualification of an experimental capability for thermal loss testing of full-size trough receiver elements; and the testing on a variety of receivers.

  20. 21 CFR 1020.10 - Television receivers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Television receivers. 1020.10 Section 1020.10 Food...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television receivers. (a) Applicability. The provisions of this section are applicable to television receivers...

  1. 49 CFR 393.88 - Television receivers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a television...

  2. 47 CFR 32.1170 - Receivables.

    Science.gov (United States)

    2010-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS.... (f) Dividends received and receivable from affiliated companies accounted for on the equity method..., matured rents, and interest receivable under monthly settlements on short-term loans, advances, and open...

  3. A zero-power radio receiver.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2004-09-01

    This report describes both a general methodology and some specific examples of passive radio receivers. A passive radio receiver uses no direct electrical power but makes sole use of the power available in the radio spectrum. These radio receivers are suitable as low data-rate receivers or passive alerting devices for standard, high power radio receivers. Some zero-power radio architectures exhibit significant improvements in range with the addition of very low power amplifiers or signal processing electronics. These ultra-low power radios are also discussed and compared to the purely zero-power approaches.

  4. Concentrated solar power generation using solar receivers

    Science.gov (United States)

    Anderson, Bruce N.; Treece, William Dean; Brown, Dan; Bennhold, Florian; Hilgert, Christoph

    2017-08-08

    Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.

  5. Compressive Sensing for Spread Spectrum Receivers

    DEFF Research Database (Denmark)

    Fyhn, Karsten; Jensen, Tobias Lindstrøm; Larsen, Torben

    2013-01-01

    to a decrease in the two design parameters. This paper investigates the use of Compressive Sensing (CS) in a general Code Division Multiple Access (CDMA) receiver. We show that when using spread spectrum codes in the signal domain, the CS measurement matrix may be simplified. This measurement scheme, named...... Compressive Spread Spectrum (CSS), allows for a simple, effective receiver design. Furthermore, we numerically evaluate the proposed receiver in terms of bit error rate under different signal to noise ratio conditions and compare it with other receiver structures. These numerical experiments show that though...

  6. Shipping/Receiving and Quality Control

    Data.gov (United States)

    Federal Laboratory Consortium — Shipping receiving, quality control, large and precise inspection and CMM machines. Coordinate Measuring Machines, including "scanning" probes, optical comparators,...

  7. Hybrid Microoptical WDM Receiver for PON Communication

    Directory of Open Access Journals (Sweden)

    Vitezslav Jerabek

    2012-01-01

    Full Text Available The paper presents the design, simulation and construction results of the wavelength division multiplex (WDM optical hybrid receiver module for the passive optical network (PON. The optical WDM receiver was constructed using system of three micromodules in the new circle topology. The optical micromodule contains multimode fiber pigtail 50/125 µm, VHGT filter with collimation lens and two microwave optoelectronics receiver micromodules (OE receiver micromodules. OE receiver micromodules were designed by use small signal equivalent electrical circuit model and noise model, from which the mathematically solved the transmittance function, which was used for calculation and simulation of the optimal frequency characteristics and signal to noise ratio. For determine the limit frequency of OE receiver micromodule, the transcendent equation with transmittance function was numerically solved. OE receiver micromodule was composed of decollimation lenses and microwave optoelectronics receivers with bandwidth 2,5 GHz and alternatively in SMD technology with bandwidth 1,25 GHz, using the thin layer hybrid technology. WDM receiver use radiation 1490 nm for internet and 1550 nm for digital TV signals download information.

  8. Variable velocity in solar external receivers

    Science.gov (United States)

    Rodríguez-Sánchez, M. R.; Sánchez-González, A.; Acosta-Iborra, A.; Santana, D.

    2017-06-01

    One of the major problems in solar external receivers is tube overheating, which accelerates the risk of receiver failure. It can be solved implementing receivers with high number of panels. However, it exponentially increases the pressure drop in the receiver and the parasitic power consumption of the Solar Power Tower (SPT), reducing the global efficiency of the SPT. A new concept of solar external receiver, named variable velocity receiver, is able to adapt their configuration to the different flux density distributions. A set of valves allows splitting in several independent panels those panels in which the wall temperature is over the limit. It increases the velocity of the heat transfer fluid (HTF) and its cooling capacity. This receiver does not only reduce the wall temperature of the tubes, but also simplifies the control of the heliostat field and allows to employ more efficient aiming strategies. In this study, it has been shown that variable velocity receiver presents high advantages with respect to traditional receiver. Nevertheless, more than two divisions per panels are not recommendable, due to the increment of the pressure drop over 70 bars. In the design point (12 h of the Spring Equinox), the use of a variable number of panels between 18 and 36 (two divisions per panel), in a SPT similar to Gemasolar, improves the power capacity of the SPT in 5.7%, with a pressure drop increment of 10 bars. Off-design, when the flux distribution is high and not symmetric (e.g. 10-11 h), the power generated by the variable velocity receiver is 18% higher than the generated by the traditional receiver, at these hours the pressure drop increases almost 20 bars.

  9. Alterations in erythrocyte survival parameters in rats after 19.5 days aboard Cosmos 782

    Science.gov (United States)

    Leon, H. A.; Serova, L. V.; Cummins, J.; Landaw, S. A.

    1978-01-01

    Rats were subjected to 19.5 days of weightless space flight aboard the Soviet biosatellite, Cosmos 782. Based on the output of CO-14, survival parameters of a cohort of erythrocytes labeled 15.5 days preflight were evaluated upon return from orbit. These were compared to vivarium control rats injected at the same time. Statistical evaluation indicates that all survival factors were altered by the space flight. The mean potential lifespan, which was 63.0 days in the control rats, was decreased to 59.0 days in the flight rats, and random hemolysis was increased three-fold in the flight rats. The measured size of the cohort was decreased, lending further support to the idea that hemolysis was accelerated during some portion of the flight. A number of factors that might be contributory to these changes are discussed, including forces associated with launch and reentry, atmospheric and environmental parameters, dietary factors, radiation, and weightlessness.

  10. Metis aboard the Solar Orbiter space mission: Doses from galactic cosmic rays and solar energetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Telloni, Daniele [INAF-Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese (Italy); INFN Section in Florence, Via Giovanni Sansone 1, 50019 Sesto Fiorentino (Italy); Fabi, Michele [INAF-Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese (Italy); University of Urbino, Department of Pure and Applied Sciences, Via Santa Chiara 27, 61029 Urbino (Italy); Grimani, Catia [INFN Section in Florence, Via Giovanni Sansone 1, 50019 Sesto Fiorentino (Italy); University of Urbino, Department of Pure and Applied Sciences, Via Santa Chiara 27, 61029 Urbino (Italy); Antonucci, Ester [INAF-Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese (Italy)

    2016-03-25

    The aim of this work is to calculate the dose released by galactic cosmic rays (GCRs) and solar energetic particles (SEPs) in the polarimeter of the Multi Element Telescope for Imaging and Spectroscopy (METIS) coronagraph [1] aboard the Solar Orbiter. This investigation is performed with a Monte Carlo method by considering the role of SEP events of proper intensity at a heliocentric distance from the Sun averaged along the spacecraft orbit. Our approach can be extended to other space missions reaching short distances from the Sun, such as Solar Probe Plus. This study indicates that the deposited dose on the whole set of polarimeter lenses and filters during ten years of the Solar Orbiter mission is of about 2000 Gy. For cerium treated lenses, a dose of 10{sup 6} Gy of gamma radiation from a {sup 60}Co source causes a few percent transmittance loss.

  11. Innovative Sea Surface Monitoring with GNSS-Reflectometry aboard ISS: Overview and Recent Results from GEROS-ISS

    DEFF Research Database (Denmark)

    Wickert, Jens; Andersen, Ole Baltazar; Bandeiras, J.

    GEROS-ISS (GEROS hereafter) stands for GNSS REflectometry, Radio Occultation and Scatterometry onboard the International Space Station. It is a scientific experiment, proposed to the European Space Agency (ESA)in 2011 for installation aboard the ISS. The main focus of GEROS is the dedicated use o...

  12. Directional Receiver for Biomimetic Sonar System

    Science.gov (United States)

    Guarato, Francesco; Andrews, Heather; Windmill, James F.; Jackson, Joseph; Gachagan, Anthony

    An ultrasonic localization method for a sonar system equipped with an emitter and two directional receivers and inspired by bat echolocation uses knowledge of the beam pattern of the receivers to estimate target orientation. Rousettus leschenaultii's left ear constitutes the model for the design of the optimal receiver for this sonar system and 3D printing was used to fabricate receiver structures comprising of two truncated cones with an elliptical external perimeter and a parabolic flare rate in the upper part. Measurements show one receiver has a predominant lobe in the same region and with similar attenuation values as the bat ear model. The final sonar system is to be mounted on vehicular and aerial robots which require remote control for motion and sensors for estimation of each robot's location.

  13. High dynamic, low volume GPS receiver

    Science.gov (United States)

    Hurd, W. J.

    1983-01-01

    A new GPS receiver concept and design are presented to meet the high dynamic and low volume requirements for range applications in missiles and drones. The receiver has the potential to satisfy all range requirements with one basic receiver, which has significant potential economic benefit over the alternate approach of using a family of receivers, each tailored for specific applications. The main new concept is to use approximate maximum likelihood estimates of pseudo range and range-rate, rather than tracking with carrier phase locked loops and code delay locked loops. Preliminary analysis indicates that receivers accelerating at 50 g or more can track with position errors due to acceleration of approximately 0.2 m/g, or 10 m at 50 g. Implementation is almost entirely digital to meet the low volume requirements.

  14. An SDR based AIS receiver for satellites

    DEFF Research Database (Denmark)

    Larsen, Jesper Abildgaard; Mortensen, Hans Peter; Nielsen, Jens Frederik Dalsgaard

    2011-01-01

    For a few years now, there has been a high interest in monitoring the global ship traffic from space. A few satellite, capable of listening for ship borne AIS transponders have already been launched, and soon the AAUSAT3, carrying two different types of AIS receivers will also be launched. One...... of the AIS receivers onboard AAUSAT3 is an SDR based AIS receiver. This paper serves to describe the background of the AIS system, and how the SDR based receiver has been integrated into the AAUSAT3 satellite. Amongst some of the benefits of using an SDR based receiver is, that due to its versatility, new...... detection algorithms are easily deployed, and it is easily adapted the new proposed AIS transmission channels....

  15. Fundamentals of GPS Receivers A Hardware Approach

    CERN Document Server

    Doberstein, Dan

    2012-01-01

    While much of the current literature on GPS receivers is aimed at those intimately familiar with their workings, this volume summarizes the basic principles using as little mathematics as possible, and details the necessary specifications and circuits for constructing a GPS receiver that is accurate to within 300 meters. Dedicated sections deal with the features of the GPS signal and its data stream, the details of the receiver (using a hybrid design as exemplar), and more advanced receivers and topics including time and frequency measurements. Later segments discuss the Zarlink GPS receiver chip set, as well as providing a thorough examination of the TurboRogue receiver, one of the most accurate yet made. Guiding the reader through the concepts and circuitry, from the antenna to the solution of user position, the book’s deployment of a hybrid receiver as a basis for discussion allows for extrapolation of the core ideas to more complex, and more accurate designs. Digital methods are used, but any analogue c...

  16. The Mitigation of Radio Noise from External Sources at Receiving Sites

    Science.gov (United States)

    2007-05-01

    to 30-MHz was used between the antenna and the voltmeter to prevent signals lower and higher in frequency from contaminating the results. This... conversion device caused harmful interference at the microwave frequencies used by the satellite terminal, but they did cause harmful levels of...and voltage . These short pulses (with steep rise and fall times) have spectral components that extend up into the HF and VHF frequencies and

  17. Decoding algorithm for vortex communications receiver

    Science.gov (United States)

    Kupferman, Judy; Arnon, Shlomi

    2018-01-01

    Vortex light beams can provide a tremendous alphabet for encoding information. We derive a symbol decoding algorithm for a direct detection matrix detector vortex beam receiver using Laguerre Gauss (LG) modes, and develop a mathematical model of symbol error rate (SER) for this receiver. We compare SER as a function of signal to noise ratio (SNR) for our algorithm and for the Pearson correlation algorithm. To our knowledge, this is the first comprehensive treatment of a decoding algorithm of a matrix detector for an LG receiver.

  18. Exploiting Redundancy in an OFDM SDR Receiver

    Directory of Open Access Journals (Sweden)

    Tomas Palenik

    2009-01-01

    Full Text Available Common OFDM system contains redundancy necessary to mitigate interblock interference and allows computationally effective single-tap frequency domain equalization in receiver. Assuming the system implements an outer error correcting code and channel state information is available in the receiver, we show that it is possible to understand the cyclic prefix insertion as a weak inner ECC encoding and exploit the introduced redundancy to slightly improve error performance of such a system. In this paper, an easy way to implement modification to an existing SDR OFDM receiver is presented. This modification enables the utilization of prefix redundancy, while preserving full compatibility with existing OFDM-based communication standards.

  19. GPU Acceleration of DSP for Communication Receivers.

    Science.gov (United States)

    Gunther, Jake; Gunther, Hyrum; Moon, Todd

    2017-09-01

    Graphics processing unit (GPU) implementations of signal processing algorithms can outperform CPU-based implementations. This paper describes the GPU implementation of several algorithms encountered in a wide range of high-data rate communication receivers including filters, multirate filters, numerically controlled oscillators, and multi-stage digital down converters. These structures are tested by processing the 20 MHz wide FM radio band (88-108 MHz). Two receiver structures are explored: a single channel receiver and a filter bank channelizer. Both run in real time on NVIDIA GeForce GTX 1080 graphics card.

  20. Global Positioning System receiver evaluation results

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, R.H.

    1993-09-01

    A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.

  1. Enlaces de datos En VHF (VDL dentro del contexto CNS/ATM para la prestación de los servicios de tránsito aéreo en Colombia

    Directory of Open Access Journals (Sweden)

    Édgar Leonardo Gómez Gómez

    2012-09-01

    Full Text Available En este artículo se analiza el protocolo de comunicaciones por enlaces de datos en VHF (VDL, el cual, junto con técnicas de posicionamiento satelital, es uno de los pilares fundamentales dentro del concepto CNS/ATM planteado por la Organización de Aviación Civil Internacional (OACI, el cual busca la implantación de nuevas tecnologías para la prestación de los servicios de tránsito aéreo en las áreas de comunicaciones, navegación y vigilancia de aeronaves a nivel mundial. Se presenta el tipo de sistemas usados actualmente por la Unidad Administrativa Especial de Aeronáutica Civil (UAEAC para la prestación de estos servicios en Colombia, y se hace un comparativo para establecer las ventajas que tiene la implantación de las nuevas tecnologías planteadas en el concepto CNS/ATM, teniendo en cuenta las condiciones particulares de terreno y de flujo de tránsito aéreo que presenta Colombia. Además, se presentan los proyectos de implementación de subredes basadas en enlaces de datos VDL más relevantes a nivel mundial, los cuales permiten obtener resultados de pruebas de funcionamiento, como un paso fundamental hacia la consolidación a nivel mundial de este tipo de tecnología.

  2. List of Nuclear Materials Licensing Actions Received

    Data.gov (United States)

    Nuclear Regulatory Commission — A catalog of all Materials Licensing Actions received for review. The catalog lists the name of the entity submitting the license application, their city and state,...

  3. Solar central receiver systems comparative economics

    Science.gov (United States)

    Eicker, P. J.

    1980-04-01

    Several major conceptual design studies of solar central receiver systems and components were completed in the last year. The results of these studies were used to compare the projected cost of electric power generation using central receiver systems with that of more conventional power generation. The cost estimate for a molten salt central receiver system is given. Levelized busbar energy cost is shown as a function of annual capacity factor indicating the fraction of the cost due to each of the subsystems. The estimated levelized busbar energy cost for a central receiver (70 to 90 mills per kilowatt hour) is compared with the levelized busbar energy cost for a new coal fired Rankine cycle plant. Sensitivities to the initial cost of coal and the delta fuel escalation are shown.

  4. Metal Mesh Filters for Terahertz Receivers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The technical objective of this SBIR program is to develop and demonstrate metal mesh filters for use in NASA's low noise receivers for terahertz astronomy and...

  5. Collector/Receiver Characterization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.

  6. Changes in Received Pronunciation: Diachronic Case Studies

    National Research Council Canada - National Science Library

    Martin Hinton

    2015-01-01

    This paper sets out to investigate changes and individual irregularities in the Received Pronunciation of a number of individuals over time and to compare them with the changes noted in contemporary RP in the literature...

  7. High-Rate Receiver Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an initial architectural and preliminary hardware design study for a high-rate receiver capable of decoding modulation suites specified by CCSDS 413.0-G-1...

  8. Digital Signal Processing Based Biotelemetry Receivers

    Science.gov (United States)

    Singh, Avtar; Hines, John; Somps, Chris

    1997-01-01

    This is an attempt to develop a biotelemetry receiver using digital signal processing technology and techniques. The receiver developed in this work is based on recovering signals that have been encoded using either Pulse Position Modulation (PPM) or Pulse Code Modulation (PCM) technique. A prototype has been developed using state-of-the-art digital signal processing technology. A Printed Circuit Board (PCB) is being developed based on the technique and technology described here. This board is intended to be used in the UCSF Fetal Monitoring system developed at NASA. The board is capable of handling a variety of PPM and PCM signals encoding signals such as ECG, temperature, and pressure. A signal processing program has also been developed to analyze the received ECG signal to determine heart rate. This system provides a base for using digital signal processing in biotelemetry receivers and other similar applications.

  9. Optical Coherent Receiver Enables THz Wireless Bridge

    DEFF Research Database (Denmark)

    Yu, Xianbin; Liu, Kexin; Zhang, Hangkai

    2016-01-01

    We experimentally demonstrated a 45 Gbit/s 400 GHz photonic wireless communication system enabled by an optical coherent receiver, which has a high potential in fast recovery of high data rate connections, for example, in disaster....

  10. Metal Mesh Filters for Terahertz Receivers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The best low-noise receiver solutions for frequencies above about 800 GHz rely on either a low-noise bolometric direct detector or a hot electron bolometric mixer....

  11. High dynamic GPS receiver validation demonstration

    Science.gov (United States)

    Hurd, W. J.; Statman, J. I.; Vilnrotter, V. A.

    1985-01-01

    The Validation Demonstration establishes that the high dynamic Global Positioning System (GPS) receiver concept developed at JPL meets the dynamic tracking requirements for range instrumentation of missiles and drones. It was demonstrated that the receiver can track the pseudorange and pseudorange rate of vehicles with acceleration in excess of 100 g and jerk in excess of 100 g/s, dynamics ten times more severe than specified for conventional High Dynamic GPS receivers. These results and analytic extensions to a complete system configuration establish that all range instrumentation requirements can be met. The receiver can be implemented in the 100 cu in volume required by all missiles and drones, and is ideally suited for transdigitizer or translator applications.

  12. Rabies: What Care Will I Receive?

    Science.gov (United States)

    ... Exposure at a Softball Tournament September 9, 2006: Horse Stabled in Tennessee Tested Positive for Rabies May ... the likelihood of rabies. You should receive a tetanus shot if you have not been immunized in ...

  13. Flexible receiver adapter formal design review

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, S.A.

    1995-06-13

    This memo summarizes the results of the Formal (90%) Design Review process and meetings held to evaluate the design of the Flexible Receiver Adapters, support platforms, and associated equipment. The equipment is part of the Flexible Receiver System used to remove, transport, and store long length contaminated equipment and components from both the double and single-shell underground storage tanks at the 200 area tank farms.

  14. A handbook for solar central receiver design

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, P.K.

    1986-12-01

    This Handbook describes central receiver technology for solar thermal power plants. It contains a description and assessment of the major components in a central receiver system configured for utility scale production of electricity using Rankine-cycle steam turbines. It also describes procedures to size and optimize a plant and discussed examples from recent system analyses. Information concerning site selection criteria, cost estimation, construction, and operation and maintenance is also included, which should enable readers to perform design analyses for specific applications.

  15. Accounts Receivables Management: Insight and Challenges

    Directory of Open Access Journals (Sweden)

    Charles Adusei

    2017-02-01

    Full Text Available This paper studied how Zoomlion Company Limited manages its accounts receivables. Based on multiple linear regression analysis, Kendall coefficient of concordance and One sample t-test, the result shows effective credit control systems by the company. However, poor monitoring and lack of effective follow up measures were the key challenges to debt management. The paper recommend stricter adherence to the credit policy and vigorously pursued effective recovery strategies and further prescribed best practices in accounts receivables management.

  16. Wire Probe Antenna (WPT) and Electric Field Detector (EFD) of Plasma Wave Experiment (PWE) aboard the Arase satellite: specifications and initial evaluation results

    Science.gov (United States)

    Kasaba, Yasumasa; Ishisaka, Keigo; Kasahara, Yoshiya; Imachi, Tomohiko; Yagitani, Satoshi; Kojima, Hirotsugu; Matsuda, Shoya; Shoji, Masafumi; Kurita, Satoshi; Hori, Tomoaki; Shinbori, Atsuki; Teramoto, Mariko; Miyoshi, Yoshizumi; Nakagawa, Tomoko; Takahashi, Naoko; Nishimura, Yukitoshi; Matsuoka, Ayako; Kumamoto, Atsushi; Tsuchiya, Fuminori; Nomura, Reiko

    2017-12-01

    This paper summarizes the specifications and initial evaluation results of Wire Probe Antenna (WPT) and Electric Field Detector (EFD), the key components for the electric field measurement of the Plasma Wave Experiment (PWE) aboard the Arase (ERG) satellite. WPT consists of two pairs of dipole antennas with 31-m tip-to-tip length. Each antenna element has a spherical probe (60 mm diameter) at each end of the wire (15 m length). They are extended orthogonally in the spin plane of the spacecraft, which is roughly perpendicular to the Sun and enables to measure the electric field in the frequency range of DC to 10 MHz. This system is almost identical to the WPT of Plasma Wave Investigation aboard the BepiColombo Mercury Magnetospheric Orbiter, except for the material of the spherical probe (ERG: Al alloy, MMO: Ti alloy). EFD is a part of the EWO (EFD/WFC/OFA) receiver and measures the 2-ch electric field at a sampling rate of 512 Hz (dynamic range: ± 200 mV/m) and the 4-ch spacecraft potential at a sampling rate of 128 Hz (dynamic range: ± 100 V and ± 3 V/m), with the bias control capability of WPT. The electric field waveform provides (1) fundamental information about the plasma dynamics and accelerations and (2) the characteristics of MHD and ion waves in various magnetospheric statuses with the magnetic field measured by MGF and PWE-MSC. The spacecraft potential provides information on thermal electron plasma variations and structure combined with the electron density obtained from the upper hybrid resonance frequency provided by PWE-HFA. EFD has two data modes. The continuous (medium-mode) data are provided as (1) 2-ch waveforms at 64 Hz (in apoapsis mode, L > 4) or 256 Hz (in periapsis mode, L < 4), (2) 1-ch spectrum within 1-232 Hz with 1-s resolution, and (3) 4-ch spacecraft potential at 8 Hz. The burst (high-mode) data are intermittently obtained as (4) 2-ch waveforms at 512 Hz and (5) 4-ch spacecraft potential at 128 Hz and downloaded with the WFC

  17. Digital coherent receiver technique for onboard receiver of future optical data relay system

    Science.gov (United States)

    Araki, Tomohiro

    2016-03-01

    A digital coherent receiver technique for an onboard receiver for use in a future space optical communication system is investigated. Digital coherent technologies comprising coherent detection and digital signal processing are confirmed to possibly increase the signal speed, improve the receiver sensitivity, and extend tolerance for the Doppler frequency shift. As a facet of expandability, the concept of a multichannel-rate receiver using a digital coherent technique is introduced. Experimental results using 2.5 Gbps DBPSK signal light demodulation are presented together with future issues involved in implementation. This study confirms that the digital coherent receiver has higher expandability than other detection techniques.

  18. End-To-END Performance of the future MOMA intrument aboard the EXOMARS MISSION

    Science.gov (United States)

    Buch, A.; Pinnick, V. T.; Szopa, C.; Grand, N.; Danell, R.; van Amerom, F. H. W.; Freissinet, C.; Glavin, D. P.; Stalport, F.; Arevalo, R. D., Jr.; Coll, P. J.; Steininger, H.; Raulin, F.; Goesmann, F.; Mahaffy, P. R.; Brinckerhoff, W. B.

    2016-12-01

    After the SAM experiment aboard the curiosity rover, the Mars Organic Molecule Analyzer (MOMA) experiment aboard the future ExoMars mission will be the continuation of the search for the organic composition of the Mars surface with the advantage that the sample will be extracted as deep as 2 meters below the martian surface to minimize effects of radiation and oxidation on organic materials. To analyse the wide range of organic composition (volatile and non volatils compounds) of the martian soil MOMA is composed with an UV laser desorption / ionization (LDI) and a pyrolysis gas chromatography ion trap mass spectrometry (pyr-GC-ITMS). In order to analyse refractory organic compounds and chirality samples which undergo GC-ITMS analysis may be submitted to a derivatization process, consisting of the reaction of the sample components with specific reactants (MTBSTFA [1], DMF-DMA [2] or TMAH [3]). To optimize and test the performance of the GC-ITMS instrument we have performed several coupling tests campaigns between the GC, providing by the French team (LISA, LATMOS, CentraleSupelec), and the MS, providing by the US team (NASA, GSFC). Last campaign has been done with the ITU models wich is similar to the flight model and wich include the oven and the taping station providing by the German team (MPS). The results obtained demonstrate the current status of the end-to-end performance of the gas chromatography-mass spectrometry mode of operation. References:[1] Buch, A. et al. (2009) J chrom. A, 43, 143-151. [2] Freissinet et al. (2011) J Chrom A, 1306, 59-71. [3] Geffroy-Rodier, C. et al. (2009) JAAP, 85, 454-459. Acknowledgements: Funding provided by the Mars Exploration Program (point of contact, George Tahu, NASA/HQ). MOMA is a collaboration between NASA and ESA (PI Goesmann, MPS). MOMA-GC team acknowledges support from the French Space Agency (CNES), French National Programme of Planetology (PNP), National French Council (CNRS), Pierre Simon Laplace Institute.

  19. Binomial congestion control at receivers for multicast

    Science.gov (United States)

    Zhang, Bing; Liu, Zengji; Xu, Yayan; Li, Zhen; Zhang, Shi

    2004-09-01

    A single rate multicast congestion control for streaming media applications called Binomial congestion control At Receivers for Multicast (BARM) is proposed. Combining aspects of window-based and rate-based congestion control, the protocol shifts most of the congestion control mechanisms to multicast receivers. The main features of BARM are as follows. (1) The protocol adopts binomial algorithm (k=l=0.5, α=0.28, β=0.2 for our implementation) to adjust congestion window, which not only provides TCP-friendliness but decreases abrupt rate fluctuations, making it suitable for real time streaming media multicast applications. (2) The binomial algorithm is executed at the receivers instead of at the sender; to do this, a congestion window is maintained and updated separately by each receiver. Hence the protocol not only has a better scalability but reduces the burden of the sender significantly and is suitable to Client/Server model. (3) The congestion window is converted to the expected receiving rate which is then fed back to the sender if permitted. Compared to window feedback scheme, rate feedback scheme is simpler and increases the scalability. (4) The representative approach is used to suppress the feedback implosion. Simulations results indicate that BARM shows good fairness, TCP-friendliness, smoothness, scalability, and acceptable responsiveness.

  20. Chiral Receiving Antenna With Low Backscattering Levels

    CERN Document Server

    Karilainen, Antti O

    2011-01-01

    Receiving antennas absorb power from incident waves, but they also re-radiate some power into surrounding space. If a receiving antenna is to be used as a sensor which should not disturb the object under study, it should scatter as little power as possible in the receiving direction. We propose to use a chiral element composed of two orthogonal chiral particles as a low-scattering sensor.The element can transmit and receive circular polarization in all directions with the Huygens' pattern. We derive the vector effective length for the antenna using the small dipole approximation for the chiral particles. We observe that the element does not backscatter, regardless of the polarization, when the incidence direction is normal to the plane of the particles. Scattered fields, scattered axial ratio, and the scattering cross section are presented. We show that the zero-backscattering property holds also for the antenna element when it is capable to receive all the available power with conjugate loading. The approxim...

  1. Characteristics of patients who receive electroconvulsive therapy.

    Science.gov (United States)

    Malla, A K

    1988-11-01

    Case records of all non-forensic psychiatric admissions (n = 5,729), over a three year period, to all the inpatient psychiatric facilities, within one geographic area were studied on a number of demographic, clinical, and treatment characteristics. Patients who had received E.C.T. were compared with those who did not receive tis treatment. The results showed that a high proportion (21%) had received E.C.T. In comparison with patients not receiving E.C.T., E.C.T. recipients were significantly older, more often female, had greater number of previous admissions, greater incidence of violent behaviour, and longer stays in hospital. E.C.T. patients did not differ from others on social class, education, and marital status, nor was E.C.T. prescribed more often to patients who had demonstrated suicidal behaviour, even if they had a diagnosis of depression. E.C.T. and non E.C.T. patients received an equal number of psychotropic drugs.

  2. The Communication Between Designer and Design Receiver

    DEFF Research Database (Denmark)

    Dai, Zheng; Dai, Yan

    2009-01-01

    When people think about a product,the first impression always mainly influences the result.Product is the medium of communication between designer and designer receiver.Because both of them have varied different experience and background,the information would be biased during the transferring...... process.The common symbols which can be recognized by both of designer and receiver are the key tools for communication.In some case,the same symbol in one product would be leads to different receiver impression.Generally,impression includes 3 aspects:aesthetics,function, and emotion.Designer needs...... to create an attractive and accurate impression in product from these 3 aspects.For facing the dilemma of communication,some experimental approaches can help designer deal with unique and diversity situations.Solving the detail problem in each step could keep the original meaning of designer....

  3. Windowed versus windowless solar energy cavity receivers

    Energy Technology Data Exchange (ETDEWEB)

    Jarvinen, P. O.

    1976-09-01

    A model for a windowed, high-temperature cavity receiver of the heated-air type is developed and used to evaluate the greenhouse effect as a method for obtaining high receiver operating efficiencies. The effects on receiver efficiency of varying the window cutoff wavelength, the amount of absorption in the window pass-band, the cavity operating temperature, and the number of windows are determined. Single windowed cavities are found to offer theoretical efficiencies comparable to windowless ones, while multiple windowed units are found to suffer from low operating efficiencies due to losses resulting from reflections at each window/air interface. A ''first order'' examination is made of the feasibility of air cooling the window to assure its survival. This appears possible if a proper combination of cooling technique and window material characteristics is selected.

  4. Patients' preferences for receiving laboratory test results.

    Science.gov (United States)

    Sabahi, Azam; Ahmadian, Leila; Mirzaee, Moghadameh; Khajouei, Reza

    2017-04-01

    The laboratory, as a diagnostic department in the hospital, plays an important role in the treatment and prevention of diseases. Paying attention to patients' preferences for communication of test results may provide a better and more responsive system for delivering these results. This study aimed to identify patient preferences regarding receiving their laboratory test results electronically and to identify the reasons behind their choice. Descriptive-analytical study. This study was carried out in 2015 with 200 patients who had access to the internet and had been referred at least once previously to the hospital laboratory department to receive their test results. Data were collected through an expert-validated questionnaire, and its reliability was confirmed by test-retest (P = .8). Data were analyzed using χ2 and marginal independence SPSS and R software. Ninety-eight percent of participants preferred to be notified by short message service when their test results were ready. All participants preferred to receive their test results online, and 82.5% (n = 165) preferred to receive both normal and abnormal test results this way. The main reason for receiving results online was time savings, which was reported by 77% of participants, followed by lowering the chance of missing the results (31%). About 40% of participants thought e-mail notification was more secure than accessing the results through a hospital website. Findings showed that although patients wanted to benefit from online services for receiving their test results, they were concerned about confidentiality and security. Before using online technologies, security measures necessary to protect patient privacy and to gain the trust of patients should be defined.

  5. Building and Testing a Portable VLF Receiver

    Science.gov (United States)

    McLaughlin, Robert; Krause, L.

    2014-01-01

    Unwanted emissions or signal noise is a major problem for VLF radio receivers. These can occur from man made sources such as power line hum, which can be prevalent for many harmonics after the fundamental 50 or 60 Hz AC source or from VLF radio transmissions such as LORAN, used for navigation and communications. Natural emissions can also be detrimental to the quality of recordings as some of the more interesting natural emissions such as whistlers or auroral chorus may be drowned out by the more common sferic emissions. VLF receivers must selectively filter out unwanted emissions and amplify the filtered signal to a record-able level without degrading the quality.

  6. Near-infrared receiver for advanced ophthalmology

    Science.gov (United States)

    Myers, Richard A.; Farrell, Richard; Zhang, Yuhua; Roorda, Austin

    2010-02-01

    We will present research on the development of an optical receiver module with a wide frequency bandwidth and excellent response to near-infrared radiation. This module is being produced to promote new imaging modalities, allowing retinal specialist to utilize established diagnostic instruments, such as scanning laser ophthalmoscopes (SLO) in a unique or more effective manner. In particular, it can be applied towards more accurate visual threshold studies in both the healthy and diseased eye. With this goal in mind, measurements of the targeted receiver's performance with and without additional amplification are presented, as is a survey of available APD detectors.

  7. Avalanche Photodiode Arrays for Optical Communications Receivers

    Science.gov (United States)

    Srinivasan, M.; Vilnrotter, V.

    2001-01-01

    An avalanche photodiode (APD) array for ground-based optical communications receivers is investigated for the reception of optical signals through the turbulent atmosphere. Kolmogorov phase screen simulations are used to generate realistic spatial distributions of the received optical field. It is shown that use of an APD array for pulse-position modulation detection can improve performance by up to 4 dB over single APD detection in the presence of turbulence, but that photon-counting detector arrays yield even greater gains.

  8. AllAboard: Visual Exploration of Cellphone Mobility Data to Optimise Public Transport.

    Science.gov (United States)

    Di Lorenzo, G; Sbodio, M; Calabrese, F; Berlingerio, M; Pinelli, F; Nair, R

    2016-02-01

    The deep penetration of mobile phones offers cities the ability to opportunistically monitor citizens' mobility and use data-driven insights to better plan and manage services. With large scale data on mobility patterns, operators can move away from the costly, mostly survey based, transportation planning processes, to a more data-centric view, that places the instrumented user at the center of development. In this framework, using mobile phone data to perform transit analysis and optimization represents a new frontier with significant societal impact, especially in developing countries. In this paper we present AllAboard, an intelligent tool that analyses cellphone data to help city authorities in visually exploring urban mobility and optimizing public transport. This is performed within a self contained tool, as opposed to the current solutions which rely on a combination of several distinct tools for analysis, reporting, optimisation and planning. An interactive user interface allows transit operators to visually explore the travel demand in both space and time, correlate it with the transit network, and evaluate the quality of service that a transit network provides to the citizens at very fine grain. Operators can visually test scenarios for transit network improvements, and compare the expected impact on the travellers' experience. The system has been tested using real telecommunication data for the city of Abidjan, Ivory Coast, and evaluated from a data mining, optimisation and user prospective.

  9. Wetlab-2 - Quantitative PCR Tools for Spaceflight Studies of Gene Expression Aboard the International Space Station

    Science.gov (United States)

    Schonfeld, Julie E.

    2015-01-01

    Wetlab-2 is a research platform for conducting real-time quantitative gene expression analysis aboard the International Space Station. The system enables spaceflight genomic studies involving a wide variety of biospecimen types in the unique microgravity environment of space. Currently, gene expression analyses of space flown biospecimens must be conducted post flight after living cultures or frozen or chemically fixed samples are returned to Earth from the space station. Post-flight analysis is limited for several reasons. First, changes in gene expression can be transient, changing over a timescale of minutes. The delay between sampling on Earth can range from days to months, and RNA may degrade during this period of time, even in fixed or frozen samples. Second, living organisms that return to Earth may quickly re-adapt to terrestrial conditions. Third, forces exerted on samples during reentry and return to Earth may affect results. Lastly, follow up experiments designed in response to post-flight results must wait for a new flight opportunity to be tested.

  10. The wearing of hydrophilic contact lenses aboard a commercial jet aircraft: I. Humidity effects on fit.

    Science.gov (United States)

    Eng, W G; Harada, L K; Jagerman, L S

    1982-03-01

    The increasing use of hydrophilic (soft) lenses in the United States hs prompted interest in the clinical investigation of these lenses under various wearing conditions. Any factor causing lens dehydration during wear may affect lens performance and ultimately cause eye discomfort. The purpose of this study was to evaluate the environmental conditions in the aircraft cabin and to observe any changes in the fit of the hydrophilic lenses that might occur during flight. A "laboratory" for testing was set up aboard a World Airways DC-10 on a scheduled round trip between Oakland, California and Honolulu, Hawaii. A keratometer was used to assess lens fit of seven subjects who were wearing hydrophilic lenses. The efficacy of using a soft lens hydrating solution on the fit of the lens was evaluated, but will also be evaluated in a future paper. Atmospheric pressure, humidity, and temperature measurements were recorded throughout the inflight study. The results showed that a decline in cabin humidity from at least 47% to 11% occurred within 30 min of takeoff. Although previous reports have indicated that there are a number of environmental factors in the aircraft that contribute to eye discomfort for lens wearers, this study indicates that low cabin humidity is possibly the most significant factor.

  11. Aeolian processes aboard a Space Station: Saltation and particle trajectory analysis

    Science.gov (United States)

    White, Bruce R.; Greeley, Ronald; Iversen, James D.; Leach, R. N.

    1987-01-01

    The Carousel Wind Tunnel (CWT) proposed to study aeolian processes aboard a Space Station consists of two concentric rotating drums. The space between the two drums comprises the wind tunnel section. Differential rates of rotation of the two drums would provide a wind velocity with respect to either drum surface. Preliminary results of measured velocity profiles made in a CWT prototype indicate that the wall bounded boundary layer profiles are suitable to simuate flat plate turbulent boundary layer flow. The two dimensional flate plate Cartesian coordinate equations of motion of a particle moving through the air are explained. In order to assess the suitability of CWT in the analysis of the trajectories of windblown particles, a series of calculations were conducted comparing cases for gravity with those of zero gravity. Results from the calculations demonstrate that a wind tunnel of the carousel design could be fabricated to operate in a space station environment and that experiments could be conducted which would yield significant results contributing to the understanding of the physics of particle dynamics.

  12. Experiment "Regeneration" Performed Aboard the Russian Spacecraft Foton-M2 in 2005

    Science.gov (United States)

    Grigoryan, Elonora; Almeida, Eduardo; Domaratskaya, Elena; Poplinskaya, Valentina; Aleinikova, Karina; Tairbekov, Murad; Mitashov, Victor

    2006-01-01

    The experiments on the newts performed earlier aboard Russian biosate llites showed that the rate of lens and tail regeneration in space wa s greater than on the ground. In parallel it was found that the numbe r of cells in S-phase was greater in space-flown animals than in the ground controls. However, it was unclear whether cell proliferation stimulation was induced by micro-g per se. Molecular mechanisms under lying the change also remained obscure. These issues were addressed b y the joint Russian-American experiment "Regeneration" flown on Foton -M2 in 2005. The method for in-flight delivering DNA precursor BrdU was developed. The experiment showed that during the flight the numbe r of S-phase cells in the regenerating eyes and tails increased. Thes e data together with those obtained earlier suggest that cell prolife ration increases in response to the effects of both micro-g and 1-g a fter return to Earth. The expression of bFGF in regenerating tissues of "flown" newts and ground controls was examined using immuno-histo chemistry. Obtained results suggest that this growth factor is a part icipant of the promotional effect of space flight upon cell prolifera tion in lens and tail regenerates.

  13. Analysis of non-methane hydrocarbons in air samples collected aboard the CARIBIC passenger aircraft

    Science.gov (United States)

    Baker, A. K.; Slemr, F.; Brenninkmeijer, C. A. M.

    2010-02-01

    The CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) is a long-term monitoring program making regular atmospheric measurements from an instrument container installed monthly aboard a passenger aircraft. Typical cruising altitudes of the aircraft allow for the study of the free troposphere and the extra-tropical upper troposphere as well as the lowermost stratosphere. CARIBIC measurements include a number of real time analyses as well as the collection of aerosol and whole air samples. These whole air samples are analyzed post-flight for a suite of trace gases, which includes non-methane hydrocarbons (NMHC). The NMHC measurement system and its analytical performance are described here. Precision was found to vary slightly by compound, and is less than 2% for the C2-C6 alkanes and ethyne, and between 1% and 6% for C7-C8 alkanes and aromatic compounds. Preliminary results from participation in a Global Atmospheric Watch (WMO) VOC audit indicate accuracies within the precision of the system. Limits of detection are 1 pptv for most compounds, and up to 3 pptv for some aromatics. These are sufficiently low to measure mixing ratios typically observed in the upper troposphere and lowermost stratosphere for the longer-lived NMHC, however, in air samples from these regions many of the compounds with shorter lifetimes (air mass history, with concentrations typically decreasing with shorter chemical lifetimes.

  14. Pineal physiology in microgravity - Relation to rat gonadal function aboard Cosmos 1887

    Science.gov (United States)

    Holley, Daniel C.; Markley, Carol L.; Soliman, Magdi R. I.; Kaddis, Farida; Krasnov, Igor'

    1991-01-01

    Results are reported from an analysis of pineal glands obtained for five male rats flown aboard an orbiting satellite for their melatonin, serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIA), and calcium content. Plasma 5-HT and 5-HIAA were measured. These parameters were compared to indicators of gonadal function: plasma testosterone concentration and spermatogonia development. Plasma melotonin was found to be low at the time of euthanasia and was not different among the experimental groups. Pineal calcium of flight animals was not different from ground controls. Pineal 5-HT and 5-HIAA in the flight group were significantly higher than those in ground controls. These findings suggest a possible increase in pineal 5-HT turnover in flight animals which may result in increased melatonin secretion. It is argued that the alteration of pinal 5-HT turnover and its expected effects on melatonin secretion may partially explain the lower plasma testosterone levels and 4-11 percent fewer spermatogonia cells observed in flight animals.

  15. On-Orbit Spatial Characterization of MODIS with ASTER Aboard the Terra Spacecraft

    Science.gov (United States)

    Xie, Yong; Xiong, Xiaoxiong

    2011-01-01

    This letter presents a novel approach for on-orbit characterization of MODerate resolution Imaging Spectroradiometer (MODIS) band-to-band registration (BBR) using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard the Terra spacecraft. The spatial resolution of ASTER spectral bands is much higher than that of MODIS, making it feasible to characterize MODIS on-orbit BBR using their simultaneous observations. The ground target selected for on-orbit MODIS BBR characterization in this letter is a water body, which is a uniform scene with high signal contrast relative to its neighbor areas. A key step of this approach is to accurately localize the measurements of each MODIS band in an ASTER measurement plane coordinate (AMPC). The ASTER measurements are first interpolated and aggregated to simulate the measurements of each MODIS band. The best measurement match between ASTER and each MODIS band is obtained when the measurement difference reaches its weighted minimum. The position of each MODIS band in the AMPC is then used to calculate the BBR. The results are compared with those derived from MODIS onboard Spectro-Radiometric Calibration Assembly. They are in good agreement, generally less than 0.1 MODIS pixel. This approach is useful for other sensors without onboard spatial characterization capability. Index Terms Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), band-to-band registration (BBR), MODerate resolution Imaging Spectroradiometer (MODIS), spatial characterization.

  16. State of spermatogenesis in rats flown aboard the biosatellite Cosmos-690. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Plakhuta-Plakutina, G.I.

    1977-01-01

    Testes of 30 rats flown aboard the biosatellite Cosmos-690 for 20.5 d and 30 rats kept in a ground-based experiment, which simulated all flight except weightlessness and acceleration, were examined morphologically. On the 10th experimental day the rats were exposed for 24 h to gamma irradiation from a /sup 137/Cs source at doses of 220, 800, and 955 rad. Tests from 60 nonirradiated rats that remained in the vivarium were used as controls. On the 1st-2nd and 26-27th post-experimental days the animals showed a significant decrease in the weight of testes, post-radiation death of spermatogonia, and important structural changes in the spermatogenic epithelium, whose level depended on the dose of irradiation and the time elapsed after the exposure. No significant differences in the weight of testes, frequency of occurrence of individual components of the spermatogenic epithelium, and time of emergence of reparative processes were noted. No modifying effect of space flight factors on the development of radiation-induced changes in the spermatogenic epithelium of rats was found.

  17. Five-Channel Infrared Laser Absorption Spectrometer for Combustion Product Monitoring Aboard Manned Spacecraft

    Science.gov (United States)

    Briggs, Ryan M.; Frez, Clifford; Borgentun, Carl E.; Bagheri, Mahmood; Forouhar, Siamak; May, Randy D.

    2014-01-01

    Continuous combustion product monitoring aboard manned spacecraft can prevent chronic exposure to hazardous compounds and also provides early detection of combustion events. As future missions extend beyond low-Earth orbit, analysis of returned environmental samples becomes impractical and safety monitoring should be performed in situ. Here, we describe initial designs of a five-channel tunable laser absorption spectrometer to continuously monitor combustion products with the goal of minimal maintenance and calibration over long-duration missions. The instrument incorporates dedicated laser channels to simultaneously target strong mid-infrared absorption lines of CO, HCl, HCN, HF, and CO2. The availability of low-power-consumption semiconductor lasers operating in the 2 to 5 micron wavelength range affords the flexibility to select absorption lines for each gas with maximum interaction strength and minimal interference from other gases, which enables the design of a compact and mechanically robust spectrometer with low-level sensitivity. In this paper, we focus primarily on absorption line selection based on the availability of low-power single-mode semiconductor laser sources designed specifically for the target wavelength range.

  18. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Bering Sea on 2015-09-04 (NCEI Accession 0137446)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137446 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  19. Physical and underway data collected aboard the NEW HORIZON during cruise NH1502 in the North Pacific Ocean on 2015-02-18 (NCEI Accession 0145830)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145830 includes physical and underway data collected aboard the NEW HORIZON during cruise NH1502 in the North Pacific Ocean on 2015-02-18. These data...

  20. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1211 in the North Pacific Ocean on 2012-07-14 (NCEI Accession 0134541)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0134541 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1211 in the North Pacific Ocean on 2012-07-14....

  1. Historical underway surface temperature data collected aboard the ship Skelton Castle on a voyage from England to India, 28 February 1800 to 3 June 1800 (NODC Accession 0095925)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Underway surface air temperature and sea water temperature were collected aboard the Skelton Castle while in route from England to Bombay India as part of the East...

  2. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1318 in the North Pacific Ocean on 2013-12-13 (NCEI Accession 0135463)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0135463 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1318 in the North Pacific Ocean on 2013-12-13....

  3. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean on 2016-06-22 (NCEI Accession 0155170)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155170 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  4. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1406 in the North Pacific Ocean on 2014-10-22 (NCEI Accession 0150629)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150629 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1406 in the North Pacific Ocean on 2014-10-22....

  5. Meteorological and navigational data collected aboard NOAA Ship Rainier in Yaquina Bay from 2014-11-21 to 2014-12-01 (NCEI Accession 0138154)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138154 contains raw meteorological and navigational data logged by the Scientific Computer System (SCS) aboard NOAA Ship Rainier in Yaquina Bay near...

  6. Profile data collected from CTD casts aboard the Thomas G. Thompson in the Northeast Pacific from 20060803 to 20060816 (NODC Accession 0043455)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These profile data were collected from CDT casts aboard the Thomas G. Thompson in the Northeast Pacific as part of an effort to understand the cause of the...

  7. Physical and underway data collected aboard the NEW HORIZON during cruise NH1313 in the North Pacific Ocean on 2013-06-04 (NCEI Accession 0132108)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132108 includes physical and underway data collected aboard the NEW HORIZON during cruise NH1313 in the North Pacific Ocean on 2013-06-04. These data...

  8. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1301 in the North Pacific Ocean on 2013-06-17 (NCEI Accession 0153498)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0153498 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1301 in the North Pacific Ocean on 2013-06-17....

  9. Bottle profile data collected aboard the USCGC SENECA in the Atlantic Ocean from 2 April 1915 to 20 May 1915 (NODC Accession 9700096)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 9700096 contains temperature and salinity profile data from bottle casts collected aboard the USCGC Seneca in the Grand Banks of Newfoundland and...

  10. Oceanographic profile data collected aboard multiple platforms worldwide from 1959-05-26 to 2012-06-03 (NCEI Accession 0098794)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0098794 contains physical and chemical oceanographic profile data collected aboard multiple ships worldwide from 1959-05-26 to 2012-06-03. These data...

  11. Signal Processing for Improved Wireless Receiver Performance

    DEFF Research Database (Denmark)

    Christensen, Lars P.B.

    2007-01-01

    This thesis is concerned with signal processing for improving the performance of wireless communication receivers for well-established cellular networks such as the GSM/EDGE and WCDMA/HSPA systems. The goal of doing so, is to improve the end-user experience and/or provide a higher system capacity...

  12. Management of Febrile Neutropenia in Patients receiving ...

    African Journals Online (AJOL)

    antifungal therapy for oral candidiassis. Eight (40%) patients received growth factors. The mean fever duration was 4.5 days (range 1–10 days). Two (10%) of the patients died. CONCLUSION: Febrile neutropenia in resource limited countries can be managed with good history and physical examination skills.

  13. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  14. immunisation fever amongst infants receiving Diphtheria

    African Journals Online (AJOL)

    PROF. EZECHUKWU

    2013-08-06

    Aug 6, 2013 ... Methods: A prospective study was conducted on a cohort of 710 in- fants who received ... immunisation, especially in infants and young children. Although generally benign and self-limiting, fever is ..... Although this method might minimise recall bias because of the short duration of memory re- call required ...

  15. Fresnel zone imaging of receiver functions

    Science.gov (United States)

    Mullick, Nirjhar; Buske, Stefan

    2014-05-01

    The receiver function method is a widely applied and powerful technique to obtain structural information of the crust and mantle. In its standard implementation, the depths to interfaces are interpreted from the arrival time delay of waves converted at these interfaces relative to the direct P waves. In recent times, common methods from exploration seismics (e.g. Kirchhoff prestack depth migration) have been used to image the converters instead. However, these methods are in principle not designed for receiver function imaging because of the usually non-uniform and less dense source-receiver coverage, which may lead to results dominated by significant migration noise. In this study, we present a new imaging technique that works by restricting the migration operator to the Fresnel zone in the vicinity of the conversion point at the converter. Both a synthetic test and an application to a real data set show great improvements of image quality over standard Kirchhoff migration results particularly in the case of less favorable source receiver geometry.

  16. Receiving Assistance and Local Food System Participation

    Directory of Open Access Journals (Sweden)

    Rebecca L. Som Castellano

    2017-02-01

    Full Text Available A body of literature has noted that local food systems (LFSs may not involve active participation by individuals with lower incomes. This is, in part, a function of racial and class hegemony, as well as physical and financial accessibility of LFSs. LFS institutions, such as farmers’ markets, have been working to facilitate receipt of food assistance programs, such as the Supplemental Nutrition Assistance Program (SNAP. Charitable assistance programs, such as food banks, have also been actively working to engage in LFSs, for example, by making local foods available. However, little research has explored the role that receiving public or charitable assistance can play in influencing LFS participation. In this article, I utilize quantitative and qualitative data collected from across the state of Ohio to examine the relationship between receiving assistance and LFS participation for women, who remain predominately responsible for food provisioning in the U.S., including among those who participate in LFSs. Quantitative results suggest that receiving assistance can increase participation in LFSs. Qualitative data provides more nuanced information about the importance of food assistance for women who want to participate in LFSs, and suggest that it is essential that food cooperatives and farmers’ markets are equipped to receive food assistance programs, such as SNAP, in order for women with lower incomes to participate in LFSs.

  17. Nicolas Receives 2004 Harry H. Hess Medal

    Science.gov (United States)

    Allègre, Claude J.

    2005-02-01

    Adolphe Nicolas received the Hess Medal at the 2004 Fall Meeting Honors Ceremony on 15 December, in San Francisco, California. The medal is given for outstanding achievements in research in the constitution and evolution of Earth and other planets. Citation. Adolphe Nicolas is a pioneer in Earth sciences. He has almost created a new field that we can name: the textural geodynamics.

  18. Forestry professors and students receive national recognition

    OpenAIRE

    Davis, Lynn

    2005-01-01

    Two Virginia Tech professors in the College of Natural Resources and the university's Society of American Foresters student chapter received awards for their accomplishments at the Society of American Foresters 2005 national convention held in Fort Worth, Texas, earlier this month.

  19. Two business professors receive Fulbright Scholar awards

    OpenAIRE

    Ho, Sookhan

    2005-01-01

    Virginia Tech Pamplin College of Business professors Larry French and Mahmood A. Khan have received Fulbright Scholar Awards to teach and conduct research abroad next year. Both faculty members teach in the MBA program at the university's Northern Virginia Center in metro Washington, D.C.

  20. Compressed Sensing-Based Direct Conversion Receiver

    DEFF Research Database (Denmark)

    Pierzchlewski, Jacek; Arildsen, Thomas; Larsen, Torben

    2012-01-01

    Due to the continuously increasing computational power of modern data receivers it is possible to move more and more processing from the analog to the digital domain. This paper presents a compressed sensing approach to relaxing the analog filtering requirements prior to the ADCs in a direct...

  1. 7 CFR 29.42 - Receiving station.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.42 Receiving station. Points at which producer tobacco is offered for marketing (other than sale at auction on a designated market), including tobacco auction warehouses, packing...

  2. Anatomy of a digital coherent receiver

    DEFF Research Database (Denmark)

    Borkowski, Robert; Zibar, Darko; Tafur Monroy, Idelfonso

    2014-01-01

    Digital coherent receivers have gained significant attention in the last decade. The reason for this is that coherent detection, along with digital signal processing (DSP) allows for substantial increase of the channel capacity by employing advanced detection techniques. In this paper, we first r...

  3. Howard Feiertag receives hospitality industry award

    OpenAIRE

    Ho, Sookhan

    2004-01-01

    Howard Feiertag, of Blacksburg, an instructor in hospitality and tourism management at Virginia Tech's Pamplin College of Business, received the inaugural Excellence in Sales and Marketing Strategy Award at the Hospitality Sales and Marketing Association/New York University Strategy Conference in New York recently.

  4. Controlled Directional Solidification of Aluminum - 7 wt Percent Silicon Alloys: Comparison Between Samples Processed on Earth and in the Microgravity Environment Aboard the International Space Station

    Science.gov (United States)

    Grugel, Richard N.; Tewari, Surendra N.; Erdman, Robert G.; Poirier, David R.

    2012-01-01

    An overview of the international "MIcrostructure Formation in CASTing of Technical Alloys" (MICAST) program is given. Directional solidification processing of metals and alloys is described, and why experiments conducted in the microgravity environment aboard the International Space Station (ISS) are expected to promote our understanding of this commercially relevant practice. Microstructural differences observed when comparing the aluminum - 7 wt% silicon alloys directionally solidified on Earth to those aboard the ISS are presented and discussed.

  5. Social effects of migration in receiving countries.

    Science.gov (United States)

    Ohndorf, W

    1989-06-01

    This paper examines the impact of post-1945 migration into Western, Middle, and Northern Europe from Southern Europe, Turkey, and Northern Africa, and migration to the traditional immigration countries by Asian and Latin American immigrants, on the social structures of receiving countries. Between 1955 and 1974, 1) traditional migration to the US and Australia became less important for European countries while traditional receiving countries accepted many immigrants from developing countries; and 2) rapid economic revival in Western and Northern Europe caused a considerable labor shortage which was filled by migrant workers especially from Southern Europe, Turkey, and Northern Africa, who stayed only until they reached their economic goals. Since 1974, job vacancies have declined and unemployment has soared. This employment crisis caused some migrants 1) to return to their countries of origin, 2) to bring the rest of their families to the receiving country, or 3) to lengthen their stay considerably. The number of refugees has also significantly increased since the mid-970s, as has the number of illegal migrants. After the mid-1970s, Europe began to experience integration problems. The different aspects of the impact of migration on social structures include 1) improvement of the housing situation for foreigners, 2) teaching migrants the language of the receiving country, 3) solving the unemployment problem of unskilled migrants, 4) improvement of educational and vocational qualifications of 2nd generation migrants, 5) development of programs to help unemployed wives of migrants to learn the language and meet indigenous women, 6) encouraging migrants to maintain their cultural identity and assisting them with reintegration if they return to their original country, 7) coping with the problems of refugees, and 8) solving the problems of illegal migration. Almost all receiving countries now severely restrict further immigration. [Those policies should result in

  6. CERN Press Office receives award from Euroscience

    CERN Multimedia

    2009-01-01

    The CERN Communication group has received an award for its efforts in communicating the LHC first beam to the media and the public. James Gillies, head of the Communication group was presented the AlphaGalileo Research Public Relations Award on Wednesday, 14 October during the Euroscience Media Award Ceremony in Hannover. "It’s great to receive this recognition," said Gillies. "Of course, we had great material to work with: the LHC is a fantastic story and one that is going to get even better. Angels, Demons and black holes also had their roles to play, but behind the media interest there’s been a lot of hard work by my team. This is for them." The CERN Communication group also works with communication professionals in all the CERN Member States and major physics labs around the world through the European Particle Physics Communication Network, and the InterAction collaboration. "Without them," says Gillies, &am...

  7. Jian Receives 2009 F. L. Scarf Award

    Science.gov (United States)

    2010-03-01

    Lan Jian has been awarded the AGU F. L. Scarf Award, given annually to recent Ph.D recipients for outstanding dissertation research that contributes directly to solar planetary sciences. Jian's thesis is entitled “Radial evolution of large-scale solar wind structures.” She was formally presented with the award at the Space Physics and Aeronomy section dinner during the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. Lan Jian received her B.S. in geophysics from University of Science and Technology of China in 2003. She received her M.S. and Ph.D. degrees in geophysics and space physics, under the supervision of Christopher T. Russell, at University of California, Los Angeles in 2006 and 2008, respectively. Her research interests include various structures in the solar wind, their origin and evolution, and their effect on the space environment of planets.

  8. Grooms receives 2011 Donald L. Turcotte Award

    Science.gov (United States)

    2012-02-01

    Ian Grooms has been awarded the AGU Donald L. Turcotte Award, given annually to recent Ph.D. recipients for outstanding dissertation research that contributes directly to the field of nonlinear geophysics. Grooms's thesis is entitled “Asymptotic and numerical methods for rapidly rotating buoyant flow.” He presented an invited talk and was formally presented with the award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. Grooms received his B.S. in mathematics from the College of William and Mary, Williamsburg, Va., in 2005. He received a Ph.D. in applied mathematics in 2011 under the supervision of Keith Julien at the University of Colorado at Boulder. His research interests include asymptotic and numerical methods for multiscale problems in geophysical fluid dynamics.

  9. Perception of older adults receiving palliative care

    Directory of Open Access Journals (Sweden)

    Fernanda Laporti Seredynskyj

    2014-06-01

    Full Text Available The present study aimed at understanding the perception of older adults who are receiving palliative oncological care on self care in relation to different stages of the disease and how such perception affected their lives. This is a qualitative study using oral history conducted with 15 older adults receiving palliative chemotherapy treatment in a health institution. The following categories emerged: social network, perspectives for confronting life, changes and spirituality. It is necessary for nursing staff to understand this process so that the measures implemented take into account all of the implications of the disease and aim at improving quality of life.   doi: 10.5216/ree.v16i2.22795.

  10. Fused silica windows for solar receiver applications

    Science.gov (United States)

    Hertel, Johannes; Uhlig, Ralf; Söhn, Matthias; Schenk, Christian; Helsch, Gundula; Bornhöft, Hansjörg

    2016-05-01

    A comprehensive study of optical and mechanical properties of quartz glass (fused silica) with regard to application in high temperature solar receivers is presented. The dependence of rupture strength on different surface conditions as well as high temperature is analyzed, focussing particularly on damage by devitrification and sandblasting. The influence of typical types of contamination in combination with thermal cycling on the optical properties of fused silica is determined. Cleaning methods are compared regarding effectiveness on contamination-induced degradation for samples with and without antireflective coating. The FEM-aided design of different types of receiver windows and their support structure is presented. A large-scale production process has been developed for producing fused silica dome shaped windows (pressurized window) up to a diameter of 816 mm. Prototypes were successfully pressure-tested in a test bench and certified according to the European Pressure Vessel Directive.

  11. Hypersensitivity reactions in patients receiving hemodialysis.

    Science.gov (United States)

    Butani, Lavjay; Calogiuri, Gianfranco

    2017-06-01

    To describe hypersensitivity reactions in patients receiving maintenance hemodialysis. PubMed search of articles published during the past 30 years with an emphasis on publications in the past decade. Case reports and review articles describing hypersensitivity reactions in the context of hemodialysis. Pharmacologic agents are the most common identifiable cause of hypersensitivity reactions in patients receiving hemodialysis. These include iron, erythropoietin, and heparin, which can cause anaphylactic or pseudoallergic reactions, and topical antibiotics and anesthetics, which lead to delayed-type hypersensitivity reactions. Many hypersensitivity reactions are triggered by complement activation and increased bradykinin resulting from contact system activation, especially in the context of angiotensin-converting enzyme inhibitor use. Several alternative pharmacologic preparations and dialyzer membranes are available, such that once an etiology for the reaction is established, recurrences can be prevented without affecting the quality of care provided to patients. Although hypersensitivity reactions are uncommon in patients receiving hemodialysis, they can be life-threatening. Moreover, considering the large prevalence of the end-stage renal disease population, the implications of such reactions are enormous. Most reactions are pseudoallergic and not mediated by immunoglobulin E. The multiplicity of potential exposures and the complexity of the environment to which patients on dialysis are exposed make it challenging to identify the precise cause of these reactions. Great diligence is needed to investigate hypersensitivity reactions to avoid recurrence in this high-risk population. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. Transient simulation of molten salt central receiver

    Science.gov (United States)

    Doupis, Dimitri; Wang, Chuan; Carcorze-Soto, Jorge; Chen, Yen-Ming; Maggi, Andrea; Losito, Matteo; Clark, Michael

    2016-05-01

    Alstom is developing concentrated solar power (CSP) utilizing 60/40wt% NaNO3-KNO3 molten salt as the working fluid in a tower receiver for the global renewable energy market. In the CSP power generation cycle, receivers undergo a daily cyclic operation due to the transient nature of solar energy. Development of robust and efficient start-up and shut-down procedures is critical to avoiding component failures due to mechanical fatigue resulting from thermal transients, thus maintaining the performance and availability of the CSP plant. The Molten Salt Central Receiver (MSCR) is subject to thermal transients during normal daily operation, a cycle that includes warmup, filling, operation, draining, and shutdown. This paper describes a study to leverage dynamic simulation and finite element analysis (FEA) in development of start-up, shutdown, and transient operation concepts for the MSCR. The results of the FEA also verify the robustness of the MSCR design to the thermal transients anticipated during the operation of the plant.

  13. Radio Astronomy Software Defined Receiver Project

    Energy Technology Data Exchange (ETDEWEB)

    Vacaliuc, Bogdan [ORNL; Leech, Marcus [Shirleys Bay Radio Astronomy Consortium; Oxley, Paul [Retired; Flagg, Richard [Retired; Fields, David [ORNL

    2011-01-01

    The paper describes a Radio Astronomy Software Defined Receiver (RASDR) that is currently under development. RASDR is targeted for use by amateurs and small institutions where cost is a primary consideration. The receiver will operate from HF thru 2.8 GHz. Front-end components such as preamps, block down-converters and pre-select bandpass filters are outside the scope of this development and will be provided by the user. The receiver includes RF amplifiers and attenuators, synthesized LOs, quadrature down converters, dual 8 bit ADCs and a Signal Processor that provides firmware processing of the digital bit stream. RASDR will interface to a user s PC via a USB or higher speed Ethernet LAN connection. The PC will run software that provides processing of the bit stream, a graphical user interface, as well as data analysis and storage. Software should support MAC OS, Windows and Linux platforms and will focus on such radio astronomy applications as total power measurements, pulsar detection, and spectral line studies.

  14. Hepatic Dysfunction in Patients Receiving Intravenous Amiodarone.

    Science.gov (United States)

    Hashmi, Ali; Keswani, Nicole R; Kim, Sharon; Graham, David Y

    2016-02-01

    Amiodarone is a commonly used antiarrhythmic drug. Hepatotoxicity following chronic oral administration occurs in 1% to 3% of patients. Hepatotoxicity following intravenous (IV) administration is infrequent but may be associated with dramatic increases in serum transaminases. We describe the incidence of liver toxicity among patients receiving IV amiodarone during a 5-year period. This was a single-center retrospective review of patients receiving IV amiodarone for any cause. The outcome measures were development of elevated serum transaminases and the relation of transaminitis to all-cause 30-day mortality. A total of 1510 patients received amiodarone intravenously between 2005 and 2011; 77 (5%) developed elevated liver enzymes. Enzyme elevation was divided into mild (100-300 IU/L), moderate (300-1000 IU/L), and severe (>1000 IU/L). The median alanine aminotransferase was 189 (37-10,006) IU/L and aspartate aminotransferase was 253 (84-12,005) IU/L. The 30-day mortality among those with transaminitis was 22%; however, no patient died of amiodarone-related liver disease. Amiodarone can cause severe elevation in liver enzymes. The incidence of severe transaminitis is low; deaths following IV amiodarone are rarely caused by drug-induced liver failure.

  15. Russian institute receives CMS Gold Award

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The Snezhinsk All-Russian Institute of Scientific Research for Technical Physics (VNIITF) of the Russian Federal Nuclear Centre (RFNC) is one of twelve CMS suppliers to receive awards for outstanding performance this year. The CMS Collaboration took the opportunity of the visit to CERN of the Director of VNIITF and his deputy to present the CMS Gold Award, which the institute has received for its exceptional performance in the assembly of steel plates for the CMS forward hadronic calorimeter. This calorimeter consists of two sets of 18 wedge-shaped modules arranged concentrically around the beam-pipe at each end of the CMS detector. Each module consists of steel absorber plates with quartz fibres inserted into them. The institute developed a special welding technique to assemble the absorber plates, enabling a high-quality detector to be produced at relatively low cost.RFNC-VNIITF Director Professor Georgy Rykovanov (right), is seen here receiving the Gold Award from Felicitas Pauss, Vice-Chairman of the CMS ...

  16. [Are domiciliary care patients receiving adequate thromboprophylaxis?].

    Science.gov (United States)

    Cátedra, B; Muñoz, F; Cabello, L

    2014-01-01

    The study aims to determine the percentage of patients treated at home with an indication of prophylaxis of thromboembolic disease (TED) according to the PRETEMED guidelines and whether they receive such prophylaxis. A cross-sectional descriptive study was conducted in Segovia Palace Health Centre (Madrid). to be included in the domiciliary care protocol. terminal patient, hospitalised or surgery in the last 3 months. The variables used include, age, sex, duration of domiciliary care, mobility, anticoagulant or antiplatelet treatment and reason, and associated and precipitating factors to calculate the risk of TED according to the PRETEMED guidelines, and if they receive such prophylaxis, by reviewing computerised medical records and meeting with the staff responsible. The study included a total of 187 patients, of whom 81% were women There was a significant differences in mean age by sex (men, 76.91 years, 95% CI; 72.59-81.24, and women, 86.72 years, 95% CI; 72.59-81.24, Pdomiciliary care have a low baseline risk of developing a TED episode in our study. There should be more emphasis placed on the prophylaxis of TED in acute medical episodes in which patients with slightly elevated risk may increase the likelihood of TED. Observational studies should be conducted to study the baseline risk and the subsequent development of TED in the population receiving home care. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  17. Microgravity Science Glovebox (MSG), Space Science's Past, Present and Future Aboard the International Space Station (ISS)

    Science.gov (United States)

    Spivey, Reggie; Spearing, Scott; Jordan, Lee

    2012-01-01

    The Microgravity Science Glovebox (MSG) is a double rack facility aboard the International Space Station (ISS), which accommodates science and technology investigations in a "workbench' type environment. The MSG has been operating on the ISS since July 2002 and is currently located in the US Laboratory Module. In fact, the MSG has been used for over 10,000 hours of scientific payload operations and plans to continue for the life of ISS. The facility has an enclosed working volume that is held at a negative pressure with respect to the crew living area. This allows the facility to provide two levels of containment for small parts, particulates, fluids, and gases. This containment approach protects the crew from possible hazardous operations that take place inside the MSG work volume and allows researchers a controlled pristine environment for their needs. Research investigations operating inside the MSG are provided a large 255 liter enclosed work space, 1000 watts of dc power via a versatile supply interface (120, 28, + 12, and 5 Vdc), 1000 watts of cooling capability, video and data recording and real time downlink, ground commanding capabilities, access to ISS Vacuum Exhaust and Vacuum Resource Systems, and gaseous nitrogen supply. These capabilities make the MSG one of the most utilized facilities on ISS. MSG investigations have involved research in cryogenic fluid management, fluid physics, spacecraft fire safety, materials science, combustion, and plant growth technologies. Modifications to the MSG facility are currently under way to expand the capabilities and provide for investigations involving Life Science and Biological research. In addition, the MSG video system is being replaced with a state-of-the-art, digital video system with high definition/high speed capabilities, and with near real-time downlink capabilities. This paper will provide an overview of the MSG facility, a synopsis of the research that has already been accomplished in the MSG, and an

  18. Exploration of the Black, Aegean, and Mediterranean Seas Aboard E/V Nautilus

    Science.gov (United States)

    Bell, K. L.; Ballard, R. D.; Brennan, M. L.; Raineault, N. A.; Shank, T. M.; Mayer, L. A.; Roman, C.; Mitchell, G. A.; Coleman, D. F.

    2012-12-01

    In the summer of 2012, the Exploration Vessel (E/V) Nautilus undertook a two-month expedition to the Black, Aegean, and Mediterranean Seas. The primary goal of the Nautilus is to create a focus of international leadership for the development and integration of leading-edge technologies, educational programs, field operations, and public outreach programs for ocean exploration, in partnership with the NOAA Office of Ocean Exploration, National Geographic Society, Office of Naval Research, and corporate partners. To do so, the program uses a complement of deep submergence vehicle systems and telepresence technologies to engage scientists, educators and the public, both at sea and ashore, allowing them to become integral members of the on-board exploration team. When discoveries are made, experts ashore are notified and brought aboard virtually within a short period of time to help guide shipboard response before the ship moves on. The 2012 expedition is comprised of four areas of interest. Extensive sidescan mapping took place off the Turkish coasts of the southern Black Sea and eastern Aegean Sea, and was followed by remotely operated vehicle (ROV) dives on targets of archaeological, geological, and biological interest. In the Black Sea, additional work was done on the porewater chemistry of the sediments in the oxic, suboxic, and anoxic zones. Nautilus returned to the Anaximander Seamounts, including Kazan, Amserdam, Thessaloniki, and Athina, to further explore active and formerly active seep sites located in 2010. Finally, based on biological and geological discoveries made on Eratosthenes Seamount in the eastern Mediterranean Sea, we returned to further study chemosynthetic vent communities and tectonic processes.;

  19. Initial Results from the STEM Student Experiences Aboard Ships (STEMSEAS) Program

    Science.gov (United States)

    Lewis, J. C.; Cooper, S. K.; Thomson, K.; Rabin, B.; Alberts, J.

    2016-12-01

    The Science Technology Engineering and Math Student Experiences Aboard Ships (STEMSEAS) program was created as a response to NSF's call (through GEOPATHS) for improving undergraduate STEM education and enhancing diversity in the geosciences. It takes advantage of unused berths on UNOLS ships during transits between expeditions. During its 2016 pilot year - which consisted of three transits on three different research vessels in different parts of the country, each with a slightly different focus - the program has gained significant insights into how best to create and structure these opportunities and create impact on individual students. A call for applications resulted in nearly 900 applicants for 30 available spots. Of these applicants, 32% are from minority groups underrepresented in the geosciences (Black, Hispanic, or American Indian) and 20% attend community colleges. The program was able to sail socioeconomically diverse cohorts and include women, veterans, and students with disabilities and from two- and four-year colleges. Twenty-three are underrepresented minorities, 6 attend community colleges, 5 attend an HBCU or tribal college, and many are at HSIs or other MSIs. While longer term impact assessment will have to wait, initial results and 6-month tracking for the first cohort indicate that these kinds of relatively short but intense experiences can indeed achieve significant impacts on students' perception of the geosciences, in their understanding of STEM career opportunities, their desire to work in a geoscience lab setting, and to incorporate geosciences into non-STEM careers. Insights were also gained into the successful makeup of mentor/leader groups, factors to consider in student selection, necessary pre- and post-cruise logistics management, follow-up activities, structure of activities during daily life at sea, increasing student networks and access to mentorships, and leveraging of pre-existing resources and ship-based opportunities

  20. A Survey of Staphylococcus sp and its Methicillin Resistance aboard the International Space Station

    Science.gov (United States)

    Bassinger, V. J.; Fontenot, S. L.; Castro, V. A.; Ott, C.; Healy, M.; Pierson, D. L.

    2004-01-01

    Background: Within the past few years, methicillin-resistant Staphylococcus aureus has emerged in environments with susceptible hosts in close proximity, such as hospitals and nursing homes. As the International Space Station (ISS) represents a semi-closed environment with a high level of crewmember interaction, an evaluation of isolates of clinical and environmental Staphylococcus aureus and coagulase negative Staphylococcus was performed to determine if this trend was also present in astronauts occupying ISS or on surfaces of the space station itself. Methods: Identification of isolates was completed using VITEK (GPI cards, BioMerieux), 16S ribosomal DNA analysis (MicroSeq 500, ABI), and Rep-PCR DNA fingerprinting (Divemilab, Bacterial Barcodes). Susceptibility tests were performed using VITEK (GPS-105 cards, BioMerieux) and resistance characteristics were evaluated by testing for the presence of the mecA gene (PBP2' MRSA test kit, Oxoid). Results: Rep-PCR analysis indicated the transfer of S. aureus between crewmembers and between crewmembers and ISS surfaces. While a variety of S. aureus were identified from both the crewmembers and environment, evaluations of the microbial population indicated minimal methicillin resistance. Results of this study indicated that within the semi-closed ISS environment, transfer of bacteria between crewmembers and their environment has been occurring, although there was no indication of a high concentration of methicillin resistant Staphylococcus species. Conclusions: While this study suggests that the spread of methicillin resistant S. aureus is not currently a concern aboard ISS, the increasing incidence of Earth-based antibiotic resistance indicates a need for continued clinical and environmental monitoring.

  1. The GNSS polarimetric radio-occultation technique to sense precipitation events: a new concept to be tested aboard PAZ Low Earth Satellite

    Science.gov (United States)

    Tomás, Sergio; Oliveras, Santi; Cardellach, Estel; Rius, Antonio

    2013-04-01

    The Radio Occultation and Heavy Precipitation (ROHP) experiment, to be conducted aboard the Spanish PAZ satellite, consists of a radio occultation (RO) mission provided with dual-polarization capabilities. The research with polarimetric RO data has the goal of assessing the capabilities and limitations of this technique to infer profiles of heavy precipitation. The technique aims to provide vertical profiles of precipitation simultaneously to the vertical profiles of thermodynamic parameters (standard RO products) perfectly collocated both in space and time. If successful, the polarimetric RO will represent the first technique able to provide these complementary information on precipitation. This is a relevant input for studies on heavy and violent rainfall events, which being poorly represented by the current-generation of Numerical Weather Prediction and General Circulation Models appear to be difficult to forecast on all time-scales. The Low Earth Orbiter hosting this experiment, to be launched in 2013, will orbit at 500 km altitude in a near-Polar orbit. The Radio Occulation payload includes a RO GNSS receiver and a dual polarization (H/V) limb oriented antenna to capture the signals of setting GNSS transmitters. NOAA and UCAR participate in the ground-segment of the radiometric experiment to enable near-real time dissemination of the level-1 standard RO products. The space-based GNSS RO technique scans the atmosphere vertically at fine resolution (close to 300 meter in the troposphere) by precisely measure the delay between a GNSS transmitter and a GNSS receiver aboard a Low Earth Orbiter, when the former is setting below or rising above the Earth limb. The standard, thermodynamical, products are extracted from the excess delay induced by the atmosphere at different layers. This presentation will not focus on this well-established application, but a novel concept using polarimetry to also retrieve rain information. The precipitation-measurement principle is

  2. Performance Driven Six-Port Receiver and Its Advantages over Low-IF Receiver Architecture

    Directory of Open Access Journals (Sweden)

    Abul Hasan

    2014-01-01

    Full Text Available This paper provides an extensive analysis of the performance of a six-port based direct conversion receiver (SPR in terms of signal quality, dynamic range, noise figure, ports matching, isolation, bandwidth, and cost. Calibration technique using multimemory polynomials has been adopted in order to improve the signal quality of the six-port receiver. The performances of the calibrated receiver are then compared with the performances of a commercially available I-Q demodulator used as a low-IF receiver. The main advantages and disadvantages of the SPR compared to the low-IF receiver are highlighted. The major advantages of the SPR come in terms of its available input frequency bandwidth and the low power requirement. The SPR system requires no external bias supply but suffers in terms of the available conversion gain. A better port matching of the SPR can be guaranteed over a wide frequency bandwidth, which mixer based receiver systems lack. The main component limiting the performance of a SPR is the diode detector. A faster and a better diode detector will alleviate some of the problems highlighted in this paper. The SPR system is calibratable and its error-vector-magnitude performance can be made better than the I-Q demodulator used as a low-IF receiver.

  3. Receivers Gather Data for Climate, Weather Prediction

    Science.gov (United States)

    2012-01-01

    Signals from global positioning system (GPS) satellites are now being used for more than just location and navigation information. By looking at the radio waves from GPS satellites, a technology developed at NASA s Jet Propulsion Laboratory (JPL) not only precisely calculates its position, but can also use a technique known as radio occultation to help scientists study the Earth s atmosphere and gravity field to improve weather forecasts, monitor climate change, and enhance space weather research. The University Corporation for Atmospheric Research (UCAR), a nonprofit group of universities in Boulder, Colorado, compares radio occultation to the appearance of a pencil when viewed though a glass of water. The water molecules change the path of visible light waves so that the pencil appears bent, just like molecules in the air bend GPS radio signals as they pass through (or are occulted by) the atmosphere. Through measurements of the amount of bending in the signals, scientists can construct detailed images of the ionosphere (the energetic upper part of the atmosphere) and also gather information about atmospheric density, pressure, temperature, and moisture. Once collected, this data can be input into weather forecasting and climate models for weather prediction and climate studies. Traditionally, such information is obtained through the use of weather balloons. In 1998, JPL started developing a new class of GPS space science receivers, called Black Jack, that could take precise measurements of how GPS signals are distorted or delayed along their way to the receiver. By 2006, the first demonstration of a GPS radio occultation constellation was launched through a collaboration among Taiwan s National Science Council and National Space Organization, the U.S. National Science Foundation, NASA, the National Oceanic and Atmospheric Administration (NOAA), and other Federal entities. Called the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC

  4. Solomon Receives 2005 Harry H. Hess Medal

    Science.gov (United States)

    Purdy, G. Michael; Solomon, Sean C.

    2006-02-01

    Sean C. Solomon received the Harry H. Hess Medal at the 2005 Fall Meeting Honors Ceremony, which was held on 7 December in San Francisco, Calif. The medal is given for outstanding achievements in research on the constitution and evolution of the Earth and other planets. It is a privilege to present Sean C. Solomon as the American Geophysical Union's Harry H. Hess Medal recipient. During more than 30 years of accomplished research he has established himself as one of the remarkable leadersin geophysical research today.

  5. Designing a heterostructure for the quantum receiver

    Science.gov (United States)

    Kiselev, A. A.; Kim, K. W.; Yablonovitch, E.

    2002-04-01

    In this letter, we develop optimal parameters for a structure which is suitable for the realization of a coherent quantum receiver. Conditions including predefined photon wavelength, strain, small Zeeman splitting of the electron levels, and large Zeeman effect for quantum-confined light holes are satisfied simultaneously for the structure based on the InGaAsP solid solutions. We are able to achieve designs with wavelengths of 1.3 and 1.55 μm that are desirable for optoelectronic applications.

  6. Efficiency of the Receivable Rotation Ratio as a Measure of the Accounts Receivable Settlement Period

    Directory of Open Access Journals (Sweden)

    Aleksandra Szpulak

    2010-01-01

    Full Text Available Accounts receivable forecasting, due to a wide range of applications in a number of financial decisions, is an important area of a company’s financial forecasts. Estimation of accounts receivable involves finding solutions for two fundamental problems: forecasting the level of daily sales revenues and estimating the accounts receivable settlement period. This paper addresses the issue of constructing reliable models to be used in forecasting accounts receivable due on deliveries and services – the trend model and the simple regression model. The postulated models, together with a range of alternative methods suggested in the literature on the field, are tested to examine the quality of the resulting estimates of the A/R settlement period. The methods postulated in the paper prove to be functional – on the one hand, the results are reliable, on the other hand, the postulated models can be constructed using readily available data. (original abstract

  7. Cardiac Arrest in Pediatric Patients Receiving Azithromycin.

    Science.gov (United States)

    Valdés, Santiago O; Kim, Jeffrey J; Niu, Mary C; de la Uz, Caridad M; Miyake, Christina Y; Moffett, Brady S

    2017-03-01

    To compare outcomes of pediatric patients treated with azithromycin compared with penicillin or cephalosporin. We hypothesized that azithromycin use would not be associated with increased cardiac mortality in the pediatric population. Retrospective cohort study from the Pediatric Health Information System database between 2008 and 2012. Patients Azithromycin was used in 5039 (6.1%); penicillin or cephalosporin was used in 77 943 (93.9%). Overall prevalence of antibiotic-associated CPR was 0.14%. Patients receiving a macrolide antibiotic had a lower prevalence of CPR compared with patients receiving a penicillin or cephalosporin (0.04% vs 0.14%, P = .04), and there was no difference in mortality. Multivariable analysis did not find an association between macrolide use and CPR. In contrast to recent adult studies, among children hospitalized for community-acquired pneumonia, azithromycin use was not associated with a greater prevalence of cardiac arrest compared with penicillin or cephalosporin use. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Parabolic Trough Receiver Heat Loss Testing (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Price, H.; Netter, J.; Bingham, C.; Kutscher, C.; Burkholder, F.; Brandemuehl, M.

    2007-03-01

    Parabolic trough receivers, or heat collection elements (HCEs), absorb sunlight focused by the mirrors and transfer that thermal energy to a fluid flowing within them. Thje absorbing tube of these receivers typically operates around 400 C (752 F). HCE manufacturers prevent thermal loss from the absorbing tube to the environment by using sputtered selective Cermet coatings on the absorber and by surrounding the absorber with a glass-enclosed evacuated annulus. This work quantifies the heat loss of the Solel UVAC2 and Schott PTR70 HCEs. At 400 C, the HCEs perform similarly, losing about 400 W/m of HCE length. To put this in perspective, the incident beam radiation on a 5 m mirror aperture is about 4500 W/m, with about 75% of that energy ({approx} 3400 W/m) reaching the absorber surface. Of the 3400 W/m on the absorber, about 3000 W/m is absorbed into the working fluid while 400 W/m is lost to the environment.

  9. Omnidirectional free-space optical receiver architecture

    Science.gov (United States)

    Murshid, Syed H.; Lovell, Gregory L.; Finch, Michael F.

    2013-05-01

    Free Space Optical (FSO) communication is the fusion of wireless technology and optical fiber communications systems. It has the potential of providing fiber optic data rates without the physical restraints of optical fiber cables. This endeavor presents a novel receiver structure with potential for omnidirectional free space optical communications. Interesting approaches for accomplishing omnidirectional free space lasercomm such as direct detection and solar blind non-line of sight UV scattering have been reported over the last few years. However, these technologies have resulted in limited distances of the order of 10 to 100 meters and data rates often limited to less than 1 Mb/s. This endeavor reports the architecture of an omnidirectional receiver setup by integrating an off the shelf detector and a fiber bundle, where the fiber bundle couples omnidirectional photons within its field of view and delivers these photons to the detector. The coupling of light from all directions into a detector is regulated by the cone of the acceptance angle of the fiber. Multiple fibers with overlapping acceptance angles provide the necessary coverage that may be needed to extract the optical signal from the free space optical channel. Simulated results showing the normalized power pattern of the system is presented to demonstrate omnidirectional potential of the structure. Theoretical power level versus distance plot for an FSO System employing On-O Keying (OOK) is also presented.

  10. U.S. President Richard Milhous Nixon Arrives Aboard U.S.S. Hornet for Apollo 11 Recovery

    Science.gov (United States)

    1969-01-01

    U.S. President Richard Milhous Nixon (center), is saluted by the honor guard of flight deck crewmen when he arrives aboard the U.S.S. Hornet, prime recovery ship for the Apollo 11 mission, to watch recovery operations and welcome the astronauts home. The recovery operation took place in the Pacific Ocean where Navy para-rescue men recovered the capsule housing the 3-man Apollo 11 crew. The crew was airlifted to safety aboard the U.S.S. Hornet, where they were quartered in a Mobile Quarantine Facility (MQF) for 21 days following the mission. The Apollo 11 mission, the first manned lunar mission, launched from the Kennedy Space Center, Florida via the Saturn V launch vehicle on July 16, 1969 and safely returned to Earth on July 24, 1969. Aboard were Neil A. Armstrong, commander; Michael Collins, Command Module (CM) pilot; and Edwin E. Aldrin Jr., Lunar Module (LM) pilot. The CM, piloted by Michael Collins remained in a parking orbit around the Moon while the LM, named 'Eagle'', carrying astronauts Neil Armstrong and Edwin Aldrin, landed on the Moon. Armstrong was the first human to ever stand on the lunar surface, followed by Edwin (Buzz) Aldrin. During 2½ hours of surface exploration, the crew collected 47 pounds of lunar surface material for analysis back on Earth. With the success of Apollo 11, the national objective to land men on the Moon and return them safely to Earth had been accomplished. The Saturn V vehicle was developed by the Marshall Space Flight Center (MSFC) under the direction of Dr. Wernher von Braun.

  11. In-situ observation of Martian neutral exosphere: Results from MENCA aboard Indian Mars Orbiter Mission (MOM)

    Science.gov (United States)

    Bhardwaj, Anil; Pratim Das, Tirtha; Dhanya, M. B.; Thampi, Smitha V.

    2016-07-01

    Till very recently, the only in situ measurements of the Martian upper atmospheric composition was from the mass spectrometer experiments aboard the two Viking landers, which covered the altitude region from 120 to 200 km. Hence, the exploration by the Mars Exospheric Neutral Composition Analyser (MENCA) aboard the Mars Orbiter Mission (MOM) spacecraft of ISRO and the Neutral Gas and Ion Mass Spectrometer (NGIMS) experiment aboard the Mars Atmosphere and Volatile ENvironment (MAVEN) mission of NASA are significant steps to further understand the Martian neutral exosphere and its variability. MENCA is a quadrupole based neutral mass spectrometer which observes the radial distribution of the Martian neutral exosphere. The analysis of the data from MENCA has revealed unambiguous detection of the three major constituents, which are amu 44 (CO2), amu 28 (contributions from CO and N2) and amu 16 (atomic O), as well as a few minor species. Since MOM is in a highly elliptical orbit, the MENCA observations pertain to different local times, in the low-latitude region. Examples of such observations would be presented, and compared with NGIMS results. Emphasis would be given to the observations pertaining to high solar zenith angles and close to perihelion period. During the evening hours, the transition from CO2 to O dominated region is observed near 270 km, which is significantly different from the previous observations corresponding to sub-solar point and SZA of ~45°. The mean evening time exospheric temperature derived using these observations is 271±5 K. These are the first observations corresponding to the Martian evening hours, which would help to provide constraints to the thermal escape models.

  12. Modified ECC ozone sonde for long-duration flights aboard isopicnic drifting balloons

    Science.gov (United States)

    Gheusi, Francois; Durand, Pierre; Verdier, Nicolas; Dulac, François; Attié, Jean-Luc; Commun, Philippe; Barret, Brice; Basdevant, Claude; Clénet, Antoine; Fontaine, Alain; Jambert, Corinne; Meyerfeld, Yves; Roblou, Laurent; Tocquer, Flore

    2015-04-01

    Since few years, the French space agency CNES has developed boundary-layer pressurized balloons (BLPB) with the capability to transport scientific payloads at isopicnic level over very long distances and durations (up to several weeks in absence of navigation limits). However, the autonomy of conventional electrochemical concentration cell (ECC) ozone sondes, that are widely used for tropospheric and stratospheric soundings, is limited to few hours due to power consumption and electrolyte evaporation (owing to air bubbling in the cathode solution). In collaboration with the French research community, CNES has developed a new ozone payload suited for long duration flights aboard BLPB. The mechanical elements (Teflon pump and motor) and the electrochemical cell of conventional ECC sondes have been kept but the electronic implementation is entirely new. The main feature is the possibility of programming periodic measurement sequences -- with possible remote control during the flight. To increase the ozone sonde autonomy, a strategy has been adopted of short measurement sequences (typically 2-3 min) regularly spaced in time (e.g. every 15 min, which is usually sufficient for air quality studies). The rest of the time, the sonde is at rest (pump motor off). The response time of an ECC sonde to an ozone concentration step is below one minute. Consequently, the measurement sequence is typically composed of a one-minute spin-up period after the pump has been turned on, followed by a one- to two-minute acquisition period. All time intervals can be adjusted before and during the flight. Results of a preliminary ground-based test in spring 2012 are first presented. The sonde provided correct ozone concentrations against a reference UV analyzer every 15 minutes during 4 days. Then we illustrate results from 16 BLBP flights launched in the low troposphere over the Mediterranean during summer field campaings in 2012 and 2013 (TRAQA and ChArMEx programmes). BLPB drifting

  13. Women at Sea: modesty, privacy, and sexual misconduct of passengers and sailors aboard Islamic ships

    Directory of Open Access Journals (Sweden)

    Khalilieh, Hassan S.

    2006-06-01

    Full Text Available The article deals with the attitude of Islamic law towards the carriage of women by water and how Muslim judicial authorities viewed their presence on ships. It discusses the conditions under which women were carried, accommodated and treated, in addition to their personal and social behavior in ships. To apply Islamic religious ethics and navigational regulations during maritime journeys, jurists instructed owners of ships, crews, and passengers how to act in the event of an immoral behavior on the part of both or either party. Women could protect themselves against temptation and sexual harassment by dressing modestly, behaving properly, and traveling with mahrams. Even though this work focuses on the Islamic Mediterranean, the article briefly describes the punishment of sexual misconduct as established in the thirteenth century C.E. in Islamic Malay. Lastly, it touches the Islamic legal position on the transportation of Muslims aboard Christian ships.

    Este artículo trata de la actitud de la ley islámica acerca del transporte marítimo de las mujeres y de cómo las autoridades jurídicas musulmanas consideraban su presencia en los barcos. Discute las condiciones bajo las cuales las mujeres eran acomodadas y tratadas en los barcos así como el comportamiento personal y social que se esperaba de ellas. Con el fin de aplicar la ética islámica y las normas marítimas, los juristas informaban a los armadores, tripulaciones y pasajeros de cómo actuar en el caso de comportamiento inmoral por alguna o varias de las partes. El trabajo se centra en el Mediterráneo Islámico, pero trata brevemente el castigo de la conducta

  14. Numerical Model of the Plasma Sheath Generated by the Plasma Source Instrument Aboard the Polar Satellite

    Science.gov (United States)

    Singh, N.; Leung, W. C.; Moore, T. E.; Craven, P. D.

    2001-01-01

    The plasma sheath generated by the operation of the Plasma Source Instrument (PSI) aboard the Polar satellite is studied by using a three-dimensional particle-in-cell (PIC) code. When the satellite passes through the region of low-density plasma, the satellite charges to positive potentials as high as 40-50 V, owing to the photoelectron emission. In such a case, ambient core ions cannot accurately be measured or detected. The goal of the onboard PSI is to reduce the floating potential of the satellite to a sufficiently low value so that the ions in the polar wind become detectable. When the PSI is operated, ion-rich xenon plasma is ejected from the satellite, such that the floating potential of the satellite is reduced and is maintained at approximately 2 V. Accordingly, in our three-dimensional PIC simulation we considered that the potential of the satellite is 2 V as a fixed bias. Considering the relatively high density of the xenon plasma in the sheath (10-10(exp 3)/cc), the ambient plasma of low density (plasma dynamics are calculated self-consistently. We found that an 'apple'-shape positive potential sheath forms surrounding the satellite. In the region near the PSI emission a high positive potential hill develops. Near the Thermal Ion Dynamics Experiment detector away from the PSI, the potentials are sufficiently low for the ambient polar wind ions to reach it. In the simulations it takes only about a couple of tens of electron gyroperiods for the sheath to reach a quasi steady state. This time is approximately the time taken by the heavy Xe(+) ions to expand up to about one average Larmor radius of electrons from the satellite surface. After this time the expansion of the sheath in directions transverse to the ambient magnetic field slows down because the electrons are magnetized. Using the quasi steady sheath, we performed trajectory calculations to characterize the detector response to a highly supersonic polar wind flow. The detected ions' velocity

  15. Observation of strong VHF-radar echoes from the E-region at 69°N and 54°N: Echo properties, relation to sporadic layers, and physical mechanisms

    Science.gov (United States)

    Rapp, Markus; Leitert, Lasse; Latteck, Ralph; Zecha, Marius; Hoffmann, Peter; Höffner, Josef; Hoppe, Ulf-Peter; La Hoz, Cesar

    For more than ten years the Leibniz-Institute of Atmospheric Physics at Rostock University in Kühlungsborn has been operating two VHF-radars (53.5 MHz) at the Arctic location Andenes (69N, 16E) as well as the mid-latitude site Kühlungsborn (54.1N 11.8E). Both radars have primarily been used for the study of strong radar echoes from the summer mesopause region known as (polar) mesosphere summer echoes or (P)MSE. PMSE occur from mid May until mid August in an altitude range from 80 -90 km, i.e., at the time of year and in the altitude range where the atmosphere is supersaturated with respect to ice such that ice particles may form, modify the D-region plasma, and lead to spectacular radar echoes. The existence of echoes from above this altitude range has generally been deemed impossible since refractive index fluctuations arising from neutral dynamics such as turbulence are effectively destroyed at these altitudes owing to the exponential increase of viscosity with height. Also, plasma instabilities which occur between 90 -110 km height produce field aligned irregularities and should not lead to detectable echoes for vertically sounding radars at polar latitudes where the magnetic field lines are essentially perpendicular to the surface. It hence comes as a surprise that our recent observations in the altitude range from 90 -115 km reveals the presence of strong radar echoes both at 69N as well as 54N. These echoes have a typical duration of less than 1 hour and extend over less than 1 km in height. They occur in the entire altitude range from 90 to 115 km with a pronounced maximum at 100 km. The seasonal variation is marked by a pronounced maximum during the summer months. This paper describes the morphology and statistics of these echoes, discusses its relation to sporadic E-layers and sporadic metal layers, and closes with an initial attempt to identify a physical mechanism responsible for these structures.

  16. Eosinophils increase in animals that received biotherapic

    Directory of Open Access Journals (Sweden)

    Pedro Gilberto Silva Morais

    2012-12-01

    Full Text Available Dairy industry is an important Brazilian economic activity participating of income generation. European breeds cattle aren’t adapted to parasites found in the tropics, like the Rhipicephalus microplus tick. Parasites can acquire resistance to allopathic products, but not to homeopathic products. We evaluate the efficacy of an antiparasiticide biotherapic against the R. microplus tick. The biotherapic was prepared according to the homeopathic pharmacopoeia recommendations from vegetable (Abrotanum and animal products (Rhipicephalus microplus, Amblyomma cajenennense, Haematobia irritans, Musca domestica, Dermatobia hominis, all diluted and vigorous shaken (dynamized in water or alcohol at a ratio of 1:99, in the 12th Centesimal Hahnemann (CH12, with limestone as the carrier. This homeophatic product found in veterinary pharmacies of Ituiutaba’s region, Minas Gerais State, is registered at Ministério da Agricultura, Pecuária e Abastecimento (MAPA. Natural tick infestation was accessed in thirty Girolando (Gir x Holstein cows with 7 to 13 year-old, by monthly counting of tick female bigger than 6 mm, from October/2009 to July/2011. Cows were divided in three groups of 10 similar animals. The treated group (T1 received roughage, concentrate and biotherapic. The placebo group (T2 received roughage, concentrate and limestone and the control group (T3 received only roughage and concentrate. T1 and T2 groups were managed together and remained in the same paddock. T3 group was separed from T1 and T2 by a wire fence. From October 2009 to September 2010 blood cell counts and serum biochemical tests were performed monthly only in T1 and T2, but visual clinical observations were made in all animals. Any group was treated with acaricide when the count’s average reached 50 or more ticks. It was necessary 7 baths with acaricide in T1 and T2, while in T3 group (control group it was necessary 19 acaricide baths to control the cattle tick. We verified

  17. Receiver based PAPR reduction in OFDMA

    KAUST Repository

    Ali, Anum Z.

    2014-05-01

    High peak-to-average power ratio is one of the major drawbacks of orthogonal frequency division multiplexing (OFDM). Clipping is the simplest peak reduction scheme, however, it requires clipping mitigation at the receiver. Recently compressed sensing has been used for clipping mitigation (by exploiting the sparse nature of clipping signal). However, clipping estimation in multi-user scenario (i.e., OFDMA) is not straightforward as clipping distortions overlap in frequency domain and one cannot distinguish between distortions from different users. In this work, a collaborative clipping removal strategy is proposed based on joint estimation of the clipping distortions from all users. Further, an effective data aided channel estimation strategy for clipped OFDM is also outlined. Simulation results are presented to justify the effectiveness of the proposed schemes. © 2014 IEEE.

  18. Morel Receives 2005 Maurice Ewing Medal

    Science.gov (United States)

    Schrag, Daniel P.; Morel, François M. M.

    2006-02-01

    François M. M. Morel received the Ewing Medal at the AGU Fall Meeting Honors Ceremony, which was held on 7 December 2005, in San Francisco, Calif. The medal is given for significant original contributions to the scientific understanding of the processes in the ocean; for the advancement of oceanographic engineering, technology, and instrumentation; and for outstanding service to marine sciences. François Morel has led the search to understand the role of metals in the ocean, starting with a focus on inorganic processes and aquatic chemistry, and leading to a blend of geochemistry, microbiology, biochemistry, and genetics. His influence comes from his research and from the way he has educated an entire community of scientists with his textbooks, with his teaching, and through his former students and postdocs who hold faculty positions at universities throughout the world.

  19. MRI in children receiving total parenteral nutrition

    Energy Technology Data Exchange (ETDEWEB)

    Quaghebeur, G. [Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG (United Kingdom)]|[Department of Paediatric Neuroradiology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom); Taylor, W.J. [Department of Paediatric Neuroradiology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom); Kingsley, D.P.E. [Department of Paediatric Neuroradiology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom); Fell, J.M.E. [Department of Gastroenterology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom); Reynolds, A.P. [Department of Chemical Pathology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom); Milla, P.J. [Department of Gastroenterology, Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH (United Kingdom)

    1996-10-01

    Cranial MRI was obtained in 13 of a group of 57 children receiving long-term parenteral nutrition, who were being investigated for hypermanganasaemia. Increased signal intensity on T1-weighted images has been reported in adult patients on long-term parenteral nutrition and with encephalopathy following chronic manganese exposure in arc welding. It has been postulated that these changes are due to deposition of the paramagnetic trace element manganese. In excess manganese is hepato- and neurotoxic and we present the correlation of whole blood manganese levels with imaging findings. The age range of our patients was 6 months to 10 years, and the duration of therapy 3 months to 10 years. In 7 children we found characteristic increased signal intensity on T1-weighted images, with no abnormality on T2-weighted images. All patients had elevated whole blood manganese levels, suggesting that the basis for this abnormality is indeed deposition of manganese within the tissues. (orig.). With 3 figs.

  20. Humboldt SK pilot biodigester receives funding

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-09-30

    The Canada-Saskatchewan Western Economic Partnership Agreement (WEPA) will provide funding for Canada's first pilot-scale biodigester to be built in Humboldt, Saskatchewan. The $208,138 pilot facility will use household garbage as well as agricultural waste such as manure and livestock operations, abattoirs and food processing to create heat or power and fertilizer. Support for this bio-energy facility, which could also reduce greenhouse gases, will come from the Prairie Agricultural Machinery Institute which has received $186,138 from Canada and Saskatchewan in the form of cost-shared federal-provincial funding. The pilot plant will test different combinations of waste material feedstocks and the characteristics of the resulting gas end products. The pilot facility will also provide design information for full-scale biodigester manufacturers in Canada. It is expected that 25 full-scale biodigesters will be constructed in Canada in the near future.

  1. Teleseismic receiver functions imaging of Siberia

    DEFF Research Database (Denmark)

    Soliman, Mohammad Youssof Ahmad; Thybo, Hans; Artemieva, Irina

    2014-01-01

    We map the lithosphere in Siberia by using the available broadband seismic data for calculation of Ps- and Sp-wave receiver functions (RF). RFs show converted waves from discontinuities in the vicinity of the seismic stations. The main objective is to image the Moho and upper mantle discontinuities......, including the lithosphere-asthenosphere boundary (LAB) beneath the study area. We construct the RF using the LQT method (Vinnik, 1977; Kind et al. 1995) in the version by Yuan et al. (1997). Rotation of ray coordinates uses the incidence angles predicted by the AK135 velocity model. This decomposes the wave...... by high-frequency S-RFs. Teleseismic converted Ps waves have higher frequency content (0.5–2 Hz) than Sp, which have an upper frequency of 0.1–0.2 Hz, and therefore Ps have about an order of magnitude better resolving power than Sp. The converted Sp-wave rarely resolve intracrustal structure, but can...

  2. The BINP receives its Golden Hadron award

    CERN Document Server

    2002-01-01

    On Thursday, 14 September, the LHC Project Leader, Lyn Evans, handed over a Golden Hadron award to Alexander Skrinsky of Russia's Budker Institute of Nuclear Physics (BINP). The prize is awarded in recognition of exceptional performances by suppliers and this year prizes were awarded to two firms, Cockerill-Sambre (Belgium) and Wah-Chang (United States), and to the Budker Institute, which was unable to receive the award at the same time as the two other recipients (see Bulletin No 34/2002, of 19 August 2002). The Russian institute has been rewarded for the particularly high-quality production of 360 dipole magnets and 185 quadrupole magnets for the LHC proton beam transfer lines.

  3. Ototoxicity in children receiving cisplatin chemotherapy

    Directory of Open Access Journals (Sweden)

    Hee Jin Jang

    2010-02-01

    Full Text Available Purpose : Cisplatin is highly effective for the treatment of solid tumors in children. However, the clinical use of cisplatin is limited by its ototoxicity. The aim of this study was to evaluate the ototoxicity in children treated with cisplatin. Methods : We performed a single institution retrospective analysis of pediatric oncology patients who received cisplatin therapy between January 2001 and January 2008. Thirty-seven patients with sufficient medical and audiologic data were included in this study. Results : The median age at the time of diagnosis was 10.7 (range 3.8&#8211;16.7 years. There were 16 males and 21 females. The underlying diseases were osteosarcoma (15 cases, medulloblastoma (14 cases, germ cell tumors (7 cases, and hepatoblastoma (1 case. The median individual dose was 100 mg/m2/cycle (56-200. The median cumulative dose was 480 mg/m2 (200-1,490. Sixteen patients (43% received cranial radiotherapy. Of the 37 patients, 17 developed hearing loss, leading to an overall incidence of 46%. Logistic regression showed that age at treatment (P=0.04 and cumulative dose of cisplatin (P=0.005 were the significant risk factors in predicting hearing loss in children treated with cisplatin. In all the patients who had hearing loss, there was neither improvement nor aggravation during the follow-up (3&#8211;68 months. Conclusion : The cumulative dose of cisplatin (&gt;500 mg/m2 and younger age at treatment (&lt;12 years were 2 most important risk factors for ototoxicity in patients treated with cisplatin. Serial audiometric evaluations are needed in the patients with risk factors during and after cisplatin treatment.

  4. URBAN POND AS A RAINWATER RECEIVER

    Directory of Open Access Journals (Sweden)

    Piotr Stachowski

    2017-02-01

    Full Text Available This paper presents the functioning of a closed pond as a small storage reservoir in the urban catchment area located in the Wilda district of Poznań. It presents the natural, hydro-geological and urban conditions and the factors conditioning the water level in the pond. Particular attention was focused upon on the pond as a rainwater receiver. The total catchment area and partial catchment area were determined. The inflow of water into the pond, with varying degrees of probability of occurrence, was calculated based on metrological data. The example of a pond in the John Paul II Park shows that this reservoir may be effectively used as rainwater receiver, without underestimating their other functions. They contribute to the increase of the underground water resources, increase the attractiveness of the recreational area and provide a natural value. However, the continuous urbanization, sealing the soil surface and the occurrence of extreme weather conditions necessitate a comprehensive look at the management of rainwater in urban areas. Calculations showed that the largest inflow of rain water occurs after a day’s rain with the probability p = 100%, and would amount to 3365 m3, and the water level in the pond would rise by only 0.25 m to a capacity of about 7000 m3. This represents 57% of the total capacity of the pond. If such an increase in the water level had occurred during the period of high water levels in the pond, it could not have damaging consequences of flooding. Only the occurrence of a day’s rain with the probability p = 10%, and capacity around 4700 m3, would completely fill the pond. Such a situation can be avoided by recultivation and desilting the bottom of the pond, where the slime collects with a capacity of 1300 m3.

  5. Full-wave receiver architecture for the homodyne motion sensor

    Science.gov (United States)

    Haugen, Peter C; Dallum, Gregory E; Welsh, Patrick A; Romero, Carlos E

    2013-11-19

    A homodyne motion sensor or detector based on ultra-wideband radar utilizes the entire received waveform through implementation of a voltage boosting receiver. The receiver includes a receiver input and a receiver output. A first diode is connected to the receiver output. A first charge storage capacitor is connected from between the first diode and the receiver output to ground. A second charge storage capacitor is connected between the receiver input and the first diode. A second diode is connected from between the second charge storage capacitor and the first diode to ground. The dual diode receiver performs voltage boosting of a RF signal received at the receiver input, thereby enhancing receiver sensitivity.

  6. Phase Noise Tolerant QPSK Receiver Using Phase Sensitive Wavelength Conversion

    DEFF Research Database (Denmark)

    Da Ros, Francesco; Xu, Jing; Lei, Lei

    2013-01-01

    A novel QPSK receiver based on a phase noise reduction pre-stage exploiting PSA in a HNLF and balanced detection is presented. Receiver sensitivity improvement over a conventional balanced receiver is demonstrated.......A novel QPSK receiver based on a phase noise reduction pre-stage exploiting PSA in a HNLF and balanced detection is presented. Receiver sensitivity improvement over a conventional balanced receiver is demonstrated....

  7. Materials International Space Station Experiment (MISSE) 5 Developed to Test Advanced Solar Cell Technology Aboard the ISS

    Science.gov (United States)

    Wilt, David M.

    2004-01-01

    The testing of new technologies aboard the International Space Station (ISS) is facilitated through the use of a passive experiment container, or PEC, developed at the NASA Langley Research Center. The PEC is an aluminum suitcase approximately 2 ft square and 5 in. thick. Inside the PEC are mounted Materials International Space Station Experiment (MISSE) plates that contain the test articles. The PEC is carried to the ISS aboard the space shuttle or a Russian resupply vehicle, where astronauts attach it to a handrail on the outer surface of the ISS and deploy the PEC, which is to say the suitcase is opened 180 deg. Typically, the PEC is left in this position for approximately 1 year, at which point astronauts close the PEC and it is returned to Earth. In the past, the PECs have contained passive experiments, principally designed to characterize the durability of materials subjected to the ultraviolet radiation and atomic oxygen present at the ISS orbit. The MISSE5 experiment is intended to characterize state-of-art (SOA) and beyond photovoltaic technologies.

  8. Results from the magnetic electron ion spectrometer (MagEIS) instruments aboard the Van Allen Probes spacecraft

    Science.gov (United States)

    Fennell, Joseph; O'Brien, Paul; Roeder, James; Reeves, Geoffrey; Claudepierre, Seth; Clemmons, James; Spence, Harlan; Blake, Bernard

    The Magnetic Electron Ion Spectrometer (MagEIS) instruments aboard the Van Allen Probes Spacecraft (formerly RBSP) measure electrons and ions in the Earth's inner and outer radiation belts. The MagEIS instruments are part of the Energetic Particle, Composition, and Thermal Plasma Suite (ECT), which also includes the Relativistic Electron Proton Telescope (REPT) and the Helium Oxygen Proton Electron (HOPE) analyzer. MagEIS consists of four magnetic electron spectrometers aboard each of the two Van Allen Probes spacecraft that measure the differential fluxes, energies, and angular distributions of electrons from 20 keV to 4 MeV. The MagEIS suite also contains a silicon-detector telescope that measures the differential fluxes, energies, and angular distributions of protons from 60 keV to 20 MeV, and helium and oxygen ions above a hundred keV/AMU. We briefly describe the instrument design and measurement technique and present a set of results from the MagEIS observations, including ultra-low frequency (ULF) modulations of energetic electron flux, and observations of electron flux enhancements associated with the recent BARREL x-ray observations.

  9. Initial Results from the Magnetic Electron Ion Spectrometer (MagEIS) Instruments Aboard the Van Allen Probes Spacecraft

    Science.gov (United States)

    Claudepierre, S. G.; Blake, J. B.; Fennell, J. F.; Clemmons, J. H.; Roeder, J. L.; Spence, H. E.; Reeves, G. D.; Van Allen Probes ECT Team

    2013-05-01

    The Magnetic Electron Ion Spectrometer (MagEIS) instruments aboard the Van Allen Probes Spacecraft (formerly RBSP) measure electrons and ions in the Earth's inner and outer radiation belts. The MagEIS instruments are part of the Energetic Particle, Composition, and Thermal Plasma Suite (ECT), which also includes the Relativistic Electron Proton Telescope (REPT) and the Helium Oxygen Proton Electron (HOPE) analyzer. MagEIS consists of four magnetic electron spectrometers aboard each of the two Van Allen Probes spacecraft that measure the differential fluxes, energies, and angular distributions of electrons from 20 keV to 4 MeV. The MagEIS suite also contains a silicon-detector telescope that measures the differential fluxes, energies, and angular distributions of protons from 60 keV to 20 MeV, and helium and oxygen ions above a hundred keV/AMU. We briefly describe the instrument design and measurement technique and present a set of initial results from the MagEIS observations, including ultra-low frequency (ULF) modulations of energetic electron flux, and observations of electron flux enhancements associated with the recent BARREL x-ray observations.

  10. Social Interactions Receive Priority to Conscious Perception.

    Science.gov (United States)

    Su, Junzhu; van Boxtel, Jeroen J A; Lu, Hongjing

    2016-01-01

    Humans are social animals, constantly engaged with other people. The importance of social thought and action is hard to overstate. However, is social information so important that it actually determines which stimuli are promoted to conscious experience and which stimuli are suppressed as invisible? To address this question, we used a binocular rivalry paradigm, in which the two eyes receive different action stimuli. In two experiments we measured the conscious percept of rival actions and found that actions engaged in social interactions are granted preferential access to visual awareness over non-interactive actions. Lastly, an attentional task that presumably engaged the mentalizing system enhanced the priority assigned to social interactions in reaching conscious perception. We also found a positive correlation between human identification of interactive activity and the promotion of socially-relevant information to visual awareness. The present findings suggest that the visual system amplifies socially-relevant sensory information and actively promotes it to consciousness, thereby facilitating inferences about social interactions.

  11. Neufeld Receives 2009 Donald L. Turcotte Award

    Science.gov (United States)

    2010-03-01

    Jerome Neufeld has been awarded the Donald L. Turcotte Award, given annually to recent Ph.D. recipients for outstanding dissertation research that contributes directly to the field of nonlinear geophysics. Neufeld's thesis is entitled “Solidification in the fast lane: Flow-induced morphological instability in geological systems.” He was formally presented with the award at the Nonlinear Geophysics Focus Group reception during the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. Jerome received his B.A.S. in engineering science from the University of Toronto in 2001, and a Ph.D. in geophysics from Yale University in 2008, under the supervision of J. S. Wettlaufer, on the impact of oceanic currents on the formation of sea ice. He is currently a fellow at the Institute of Theoretical Geophysics, University of Cambridge, working on the fluid dynamics of geophysical systems including carbon dioxide sequestration, the influence of flow on the crystal structure of mushy layers, and the evolution of icicles.

  12. CERN safety expert receives international award

    CERN Multimedia

    2005-01-01

    On 18 December 2004, the President of the Swiss Electro-technical Committee, Martin Reichle (left), presented the award to Helmut Schönbacher. Helmut Schönbacher, of the Safety Commission at CERN, has received, the "1906 Award" of the International Electrotechnical Commission (IEC) for his standardisation work on the influence of ionizing radiation on insulating materials. From 1986 until 2004, Schönbacher was leader of a working group on radiation composed of internationally recognised experts. It edited standards of the IEC 60544 series on the determination of the effects of ionizing radiation on electrical insulating materials. The working group also edited three IEC Technical Reports on the determination of long-term radiation ageing in polymers. This standardisation work and long-term experience from CERN on the radiation ageing of materials also contributed to research coordination programmes of the International Atomic Energy Agency (IAEA). From 1968 until 1988, Schönbacher was a member of the Rad...

  13. Crustal Structure beneath Mexico from Receiver Functions

    Science.gov (United States)

    Espindola, V.; Quintanar, L.; Espindola, J.

    2011-12-01

    The Servicio Sismológico Nacional (SSN) is Mexico's official organism in charge of the observation of seismicity in the country. Operated by the Universidad Nacional Autonoma de Mexico, it counts with 32 broadband stations deployed throughout the country. The coverage includes most of the geologic provinces of the territory, which vary widely in their geologic characteristics. The availability of records from teleseisms at those stations makes feasible to obtain sound and homogeneous estimates of the structure of the crust in the Mexican territory through the analysis of receiver functions (RF). In this work we present the results of the analysis of RF obtained from events registered from 1998 to 2009 in the 32 stations of the SSN. The RF technique, which uses converted phases at major velocity discontinuities, is a well established technique to infer the velocity contrasts and thickness of the underlying crust. Using this method we were able to infer the depth of the Moho, a major intracrustal discontinuity and in some cases the depth to the base of the subducting plate. We present maps of crustal thickness in Mexico, which varies between about 29 km in the Yucatan peninsula to more than 40 km in central Mexico. Poisson's coefficient varies between 0.19 and 0.30. The position of the descending slab shows a large variation in the subduction angle (from about 6° in the SE margin of the Pacific coast to about 60° in the NW ) as has been found from other techniques.

  14. Infant position in neonates receiving mechanical ventilation.

    Science.gov (United States)

    Rivas-Fernandez, May; Roqué I Figuls, Marta; Diez-Izquierdo, Ana; Escribano, Joaquin; Balaguer, Albert

    2016-11-07

    In patients of various ages undergoing mechanical ventilation (MV), it has been observed that positions other than the standard supine position, such as the prone position, may improve respiratory parameters. The benefits of these positions have not been clearly defined for critically ill newborns receiving MV.This is an update of a review first published in 2005 and last updated in 2013. Primary objectiveTo assess the effects of different positioning of newborn infants receiving MV (supine vs prone, lateral decubitus or quarter turn from prone) in improving short-term respiratory outcomes. Secondary objectiveTo assess the effects of different positioning of newborn infants receiving MV on mortality and neuromotor and developmental outcomes over the long term, and on other complications of prematurity. We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8), MEDLINE via PubMed (1966 to 22 August 2016), Embase (1980 to 22 August 2016) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 22 August 2016). We also searched clinical trials databases, conference proceedings and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. Randomised and quasi-randomised clinical trials comparing different positions in newborns receiving mechanical ventilation. Three unblinded review authors independently assessed trials for inclusion in the review and extracted study data. We used standard methodological procedures as expected by The Cochrane Collaboration and assessed the quality of the evidence using the GRADE approach. If the meta-analysis was not appropriate owing to substantial clinical heterogeneity between trials, we presented review findings in narrative format. We included in this review 19 trials involving 516 participants. Seven of the included studies (N = 222) had not been evaluated in the

  15. [Travel Preparations for Patients Receiving Peritoneal Dialysis].

    Science.gov (United States)

    Lu, Shu-Chi; Lin, Wen-Chuan

    2018-02-01

    People who receive peritoneal dialysis (PD) have more freedom than those who are on hemodialysis. However, some PD patients have difficulty adapting to their new environment and thus remain largely homebound. When they work or travel abord, who cannot rely wholly on others, these patients must handle certain life problems alone. It is essential for nursing staff to help PD patients to prepare for overcoming typical inconveniences, improving quality of life, and handling unfamiliar environments. The present study assists patients to arrange domestic and foreign tourism and to participate in various activities. The intervention teaches the pre-assessment of tourism, the assessment and selection of the sterile environment for exchange, the arrangements for dialysate, planning for handling complications, the travel matters attention, and other tourist information using group or individual instruction. It is expected that patients with peritoneal dialysis will be more willing to leave their houses and be better prepared to travel, which should lead to their having more fun and to their greater enjoyment of life.

  16. Patrick Janot receives the CNRS silver medal

    CERN Multimedia

    2005-01-01

    Patrick Janot during the award ceremony. (Photo Schwemling, Paris) On 25 November, Patrick Janot of the CERN Physics Department received the CNRS silver medal for IN2P3 (Institut national de physique nucléaire et de physique des particules). This prize, one of the most prestigious awarded by the French research centre, is given to scientists for the 'originality, quality and importance of their work, as recognised both nationally and internationally'. Patrick Janot joined the ALEPH collaboration, one of the four experiments at LEP, then under construction, in 1987. First a CERN Fellow, he went on to work for the CNRS at LAL in 1989. Together with his team, he developed innovative algorithms for the reconstruction of events. This work and others earned him the bronze CNRS medal in 1993, which is awarded to scientists for their first achievements. In 1997, he became a permanent physicist at CERN, where he continued to work for ALEPH. He was appointed LEP scientific co-ordinator for the last two years of the ac...

  17. CERN Web Pages Receive a Makeover

    CERN Multimedia

    2001-01-01

    Asudden allergic reaction to the colour turquoise? Never fear, from Monday 2 April you'll be able to click in the pink box at the top of the CERN users' welcome page to go to the all-new welcome page, which is simpler and better organized. CERN's new-look intranet is the first step in a complete Web-makeover being applied by the Web Public Education (WPE) group of ETT Division. The transition will be progressive, to allow users to familiarize themselves with the new pages. Until 17 April, CERN users will still get the familiar turquoise welcome page by default, with the new pages operating in parallel. From then on, the default will switch to the new pages, with the old ones being finally switched off on 25 May. Some 400 pages have received the makeover treatment. For more information about the changes to your Web, take a look at: http://www.cern.ch/CERN/NewUserPages/ Happy surfing!

  18. Diffuse exanthema in a patient receiving varenicline.

    Science.gov (United States)

    Song, Wei; Miller, William A

    2008-07-01

    A diffuse exanthema in a patient receiving varenicline is reported. A 71-year-old white woman, who was initially admitted to the hospital for elective vascular bypass surgery, had a three-day history of a diffuse rash, severe itching, and moderate headache. Her symptoms started two days before her admission. She denied having a fever, chills, nausea, vomiting, diarrhea, and flulike symptoms. She also denied having had contact with anyone who was ill, tick or insect bites, exposure to cats, or any changes in her diet, habits, or personal hygiene. Her medical problems included peripheral vascular disease, chronic obstructive pulmonary disease (COPD), dyslipidemia, hypertension, and hypothyroidism. In addition to several medications she had been taking for over 2 years, she had been taking varenicline as an aid for smoking cessation for eight days. The patient had been smoking for 40 years. The bright-red rash covered 70% of her torso and four extremities. She had mild swelling in her cheeks, but not on the eyelids or lips. Both of her lungs were clear on auscultation, with distant breath sounds caused by her COPD. Varenicline was discontinued, and her symptoms had completely resolved by the eighth day following discontinuation of the medication. While it is possible that other medications caused her symptoms, she had been taking most of them for over 2 years and all of them for over 1 year. Also, continuation of these drugs did not prevent her symptoms from resolving, nor did it cause a recurrence of the skin reaction. A patient developed diffuse exanthema after being treated with varenicline.

  19. 47 CFR 15.117 - TV broadcast receivers.

    Science.gov (United States)

    2010-10-01

    ... portion of a TV broadcast receiver, tuning aids of the same type and comparable capability and quality... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV broadcast receivers. 15.117 Section 15.117... TV broadcast receivers. (a) All TV broadcast receivers shipped in interstate commerce or imported...

  20. Assessment of L5 receiver performance in presence of interference using a realistic receiver simulator

    OpenAIRE

    Bastide, Frédéric; Macabiau, Christophe; Akos, Dennis; Roturier, Benoit

    2003-01-01

    International audience; In the frame of the GPS modernization program, a third civil GPS signal, called L5, will be broadcasted by the first Block IIF satellites launched in 2005. The signal band is located in an ARNS band so that it is of particular interest for users such as civil aviation. It is expected to increase accuracy, availability, integrity and continuity of service. A receiver dedicated to this signal requires special design. Signal modulation is different from that used on the L...

  1. 10 day flight performance of the plant generic bioprocessing apparatus (PGBA) plant growth facility aboard STS-77

    Science.gov (United States)

    Hoehn, Alex; Chamberlain, Dale J.; Forsyth, Sasha W.; Hanna, David S.; Scovazzo, Paul; Horner, Michael B.; Stodieck, Louis S.; Todd, Paul; Heyenga, A. Gerard; Kliss, Mark H.; Bula, Raymond; Yetka, Robert

    1997-01-01

    PGBA, a plant growth facility developed for space flight biotechnology research, successfully grew a total of 30 plants in a closed, multi-crop chamber for 10 days aboard the Space Shuttle Endeavor (STS-77). Artemisia annua, Catharanthus roseus, Pinus taeda, Spinacia oleracea and Trifolium repens were the five species studied during this mission. The primary mission objectives were to study the effects of microgravity for commercial and pharmaceutical production purposes. PGBA is a payload that represents a consortium of interests including BioServe Space Technologies (payload sponsor), NASA Ames Research Center (Controlled Ecological Life Support System, CELSS, Flight Program), Wisconsin Center for Space Automation and Robotics (WCSAR), and industrial affiliates (spaceflight effects on plants and formation of plant products such as pharmaceuticals). Although BioServe is responsible for the flight hardware development and integration of PGBA, NASA Ames, WSCAR and industrial affiliates provide significant hardware subsystems and technical biological expertise support.

  2. 10 day flight performance of the plant generic bioprocessing apparatus (PGBA) plant growth facility aboard STS-77

    Energy Technology Data Exchange (ETDEWEB)

    Hoehn, A.; Chamberlain, D.J.; Forsyth, S.W.; Hanna, D.S.; Scovazzo, P.; Horner, M.B.; Stodieck, L.S.; Todd, P. [BioServe Space Technologies CU Campus Box 429 Boulder, Colorado80309-0429 (United States); Heyenga, A.G.; Kliss, M.H. [NASA Ames Research Center Space Technology Division M/S 239 Moffett Field, California94035-1000 (United States); Bula, R.; Yetka, R. [Wisconsin Center for Space Automation and Robotics (WCSAR), 1415 Engineering Drive Madison, Wisconsin53706-1691 (United States)

    1997-01-01

    PGBA, a plant growth facility developed for space flight biotechnology research, successfully grew a total of 30 plants in a closed, multi-crop chamber for 10 days aboard the Space Shuttle Endeavor (STS-77). {ital Artemisia annua, Catharanthus roseus, Pinus taeda, Spinacia oleracea and Trifolium repens} were the five species studied during this mission. The primary mission objectives were to study the effects of microgravity for commercial and pharmaceutical production purposes. PGBA is a payload that represents a consortium of interests including BioServe Space Technologies (payload sponsor), NASA Ames Research Center (Controlled Ecological Life Support System, CELSS, Flight Program), Wisconsin Center for Space Automation and Robotics (WCSAR), and industrial affiliates (spaceflight effects on plants and formation of plant products such as pharmaceuticals). Although BioServe is responsible for the flight hardware development and integration of PGBA, NASA Ames, WSCAR and industrial affiliates provide significant hardware subsystems and technical biological expertise support. {copyright} {ital 1997 American Institute of Physics.}

  3. Measurements of Acidic Gases and Aerosol Species Aboard the NASA DC-8 Aircraft During the Pacific Exploratory Mission in the Tropics (PEM-Tropics A)

    Science.gov (United States)

    Talbot, Robert W.; Dibb, Jack E.

    1999-01-01

    We received funding to provide measurements of nitric acid (HNO3), formic acid (HCOOH), acetic acid (CH3COOH), and the chemical composition of aerosols aboard the NASA Ames DC-8 research aircraft during the PEM-Tropics A mission. These measurements were successfully completed and the final data resides in the electronic archive (ftp-gte.larc.nasa.gov) at NASA Langley Research Center. For the PEM-Tropics A mission the University of New Hampshire group was first author of four different manuscripts. Three of these have now appeared in the Journal of Geophysical Research-Atmospheres, included in the two section sections on PEM-Tropics A. The fourth manuscript has just recently been submitted to this same journal as a stand alone paper. All four of these papers are included in this report. The first paper (Influence of biomass combustion emissions on the distribution of acidic trace gases over the Southern Pacific basin during austral springtime) describes the large-scale distributions of HNO3, HCOOH, and CH3COOH. Arguments were presented to show, particularly in the middle tropospheric region, that biomass burning emissions from South America and Africa were a major source of acidic gases over the South Pacific basin. The second paper (Aerosol chemical composition and distribution during the Pacific Exploratory Mission (PEM) Tropics) covers the aerosol aspects of our measurement package. Compared to acidic gases, O3, and selected hydrocarbons, the aerosol chemistry showed little influence from biomass burning emissions. The data collected in the marine boundary layer showed a possible marine source of NH3 to the troposphere in equatorial areas. This source had been speculated on previously, but our data was the first collected from an airborne platform to show its large-scale features. The third paper (Constraints on the age and dilution of Pacific Exploratory Mission-Tropics biomass burning plumes from the natural radionuclide tracer Pb-210) utilized the unexpectedly

  4. The behavior of subluminous X-ray transients near the Galactic center as observed using the X-ray telescope aboard Swift

    NARCIS (Netherlands)

    Degenaar, N.; Wijnands, R.

    2009-01-01

    In this paper we report on the spectral analysis of seven X-ray transients, which were found to be active during a monitoring campaign of the Galactic center carried out in 2006 and 2007 using the X-ray telescope aboard the Swift satellite. This campaign detected new outbursts of five known X-ray

  5. Synthetic torpor: A method for safely and practically transporting experimental animals aboard spaceflight missions to deep space

    Science.gov (United States)

    Griko, Yuri; Regan, Matthew D.

    2018-02-01

    Animal research aboard the Space Shuttle and International Space Station has provided vital information on the physiological, cellular, and molecular effects of spaceflight. The relevance of this information to human spaceflight is enhanced when it is coupled with information gleaned from human-based research. As NASA and other space agencies initiate plans for human exploration missions beyond low Earth orbit (LEO), incorporating animal research into these missions is vitally important to understanding the biological impacts of deep space. However, new technologies will be required to integrate experimental animals into spacecraft design and transport them beyond LEO in a safe and practical way. In this communication, we propose the use of metabolic control technologies to reversibly depress the metabolic rates of experimental animals while in transit aboard the spacecraft. Compared to holding experimental animals in active metabolic states, the advantages of artificially inducing regulated, depressed metabolic states (called synthetic torpor) include significantly reduced mass, volume, and power requirements within the spacecraft owing to reduced life support requirements, and mitigated radiation- and microgravity-induced negative health effects on the animals owing to intrinsic physiological properties of torpor. In addition to directly benefitting animal research, synthetic torpor-inducing systems will also serve as test beds for systems that may eventually hold human crewmembers in similar metabolic states on long-duration missions. The technologies for inducing synthetic torpor, which we discuss, are at relatively early stages of development, but there is ample evidence to show that this is a viable idea and one with very real benefits to spaceflight programs. The increasingly ambitious goals of world's many spaceflight programs will be most quickly and safely achieved with the help of animal research systems transported beyond LEO; synthetic torpor may

  6. Superior Coherent Receivers for AF Relaying with Distributed Alamouti Code

    KAUST Repository

    Khan, Fahd Ahmed

    2012-01-01

    Coherent receivers are derived for a pilot-symbol aided distributed Alamouti-coded system with imperfect channel state information. The derived coherent receivers do not perform channel estimation but rather use the received pilot signals for decoding. The derived receiver metrics use the statistics of the channel to give improved performance. The performance is further improved by using the decision history. Simulation results show that a performance gain of up to 1.8 dB can be achieved for the new receivers with decision history as compared with the conventional mismatched coherent receiver. © 2011 IEEE.

  7. The 2010 Haiti earthquake: a pathology perspective aboard the USNS Comfort.

    Science.gov (United States)

    Hussey, Sean M; Dukette, Phillip J; Dunn, Scott H; Evans, Toinette J; Oakes, Natalie Y; Gleeson, Todd D; Donahue, Timothy F

    2011-04-01

    The US Navy hospital ship USNS Comfort played an integral role in the initial phases of Operation Unified Response-Haiti following the devastating earthquake that struck near Port-Au-Prince, Haiti, on January 12, 2010. Deployed to Haiti from its home in Baltimore, Maryland, just 4 days after the earthquake, the USNS Comfort would become the region's primary tertiary casualty receiving center for 6 weeks. The pathology and laboratory department staff onboard the ship helped support the mission and experienced unique mass casualty/disaster relief scenarios while underway. This article reviews the accounts of the core laboratory, microbiology, anatomic pathology, and blood bank divisions on the USNS Comfort from the chaotic first few weeks to the final patient discharge 40 days after Operation Unified Response-Haiti began.

  8. Solar Central Receiver Hybrid Power Systems sodium-cooled receiver concept. Final report. Volume III. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    The overall, long term objective of the Solar Central Receiver Hybrid Power System is to identify, characterize, and ultimately demonstrate the viability and cost effectiveness of solar/fossil, steam Rankine cycle, hybrid power systems that: (1) consist of a combined solar central receiver energy source and a nonsolar energy source at a single, common site, (2) may operate in the base, intermediate, and peaking capacity modes, (3) produce the rated output independent of variations in solar insolation, (4) provide a significant savings (50% or more) in fuel consumpton, and (5) produce power at the minimum possible cost in mills/kWh. It is essential that these hybrid concepts be technically feasible and economically competitive with other systems in the near to mid-term time period (1985-1990) on a commercial scale. The program objective for Phase I is to identify and conceptually characterize solar/fossil steam Rankine cycle, commercial-scale, power plant systems that are economically viable and technically feasible. This volume contains appendices to the conceptual design and systems analysis studies gien in Volume II, Books 1 and 2. (WHK)

  9. A Bluetooth-enabled HiperLAN/2 receiver

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2003-01-01

    n our SDR project we aim to combine a GFSK receiver (Bluetooth) with an OFDM receiver (HiperLAN/2). Other WLAN standards use the same frequency bands and modulation techniques. So our Bluetooth-enabled HiperLAN/2 receiver can easily be adapted to other WLAN standards. This paper focuses on the

  10. A Bluetooth-enabled HiperLan/2 Receiver

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2003-01-01

    In our SDR project we aim to combine a GFSK receiver (Bluetooth) with an OFDM receiver (HiperLAN/2). Other WLAN standards use the same frequency bands and modulation techniques. So our Bluetooth-enabled HiperLAN/2 receiver can easily be adapted to other WLAN standards. This paper focuses on the

  11. 42 CFR 436.110 - Individuals receiving cash assistance.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Individuals receiving cash assistance. 436.110... Mandatory Coverage of the Categorically Needy § 436.110 Individuals receiving cash assistance. (a) A Medicaid agency must provide Medicaid to individuals receiving cash assistance under OAA, AFDC, AB, APTD...

  12. 42 CFR 435.120 - Individuals receiving SSI.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Individuals receiving SSI. 435.120 Section 435.120..., Blind, and Disabled § 435.120 Individuals receiving SSI. Except as allowed under § 435.121, the agency must provide Medicaid to aged, blind, and disabled individuals or couples who are receiving or are...

  13. Noise and intercept point calculation for modern radio receiver planning

    DEFF Research Database (Denmark)

    Iversen, Christian Rye; Kolding, T. E.

    2001-01-01

    The paper presents analytical expressions for determining noise and intercept points for cascaded radio receiver stages. The theory allows for active receiver stages with frequency selectivity and flexible impedance levels. This makes the method highly usable for planning of modem receivers where...

  14. RECEIVE SIGNAL STRENGTH PREDICTION IN THE GSM BAND ...

    African Journals Online (AJOL)

    In this work, GSM receive signal strength was monitored in an indoor environment. Samples of GSM receive signal strength was measured on a Mobile Equipment (ME). One-dimensional multilevel wavelet decomposition technique was used to predict the fading phenomenon of the GSM receive signal strength measured.

  15. 10 CFR 733.5 - Allegations received by DOE.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  16. 49 CFR 220.33 - Receiving a radio transmission.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Receiving a radio transmission. 220.33 Section 220... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Radio and Wireless Communication Procedures § 220.33 Receiving a radio transmission. (a) Upon receiving a radio call, an employee shall promptly...

  17. IMPROVEMENT WAYS OF ACCOUNTING AND INTERNAL AUDIT OF ENTERPRISE RECEIVABLES

    Directory of Open Access Journals (Sweden)

    V. D. Zelikman

    2014-06-01

    Full Text Available Purpose. Determination and substantiation of ways to improve accounting and internal audit of receivables at the enterprises. Methodology.The basic principles and ways for improvement of accounting and internal audit systems that should help Ukrainian enterprises to optimize receivables are considered. Findings. It is proved that the receivables optimization is possible on the basis of improving its accounting and internal audit. The basic ways for improvement of accounting and internal audit of receivable are determined. They are: improvement of normative coverage of receivables at the enterprises; providing further harmonization of financial and tax accounting in the part of formation of the doubtful debt receivables, accounting of bad and doubtful receivables and etc. The formation of department for internal audit to control the doubtful and bad debts; providing the timely control of the receivables and payables ratio; determination and support of the optimal value of the receivables at the enterprises. Originality. Improvement of accounting and internal audit of receivables at the enterprises by the way of development of internal audit system and optimization of the receivables size. Practical value. The proposed recommendations will improve the accounting and internal audit system of receivables at the enterprises of Ukraine.

  18. Seismic Imaging of Receiver Functions at Virtual Receivers in Ryukyu Arc, Japan

    Science.gov (United States)

    Murakoshi, T.; Takenaka, H.; Komatsu, M.; Yamada, N.

    2016-12-01

    This study describes the seismic images of the crust and uppermost mantle beneath the Ryukyu Arc, Japan by using S-wavevector receiver functions (SWV-RFs) analysis at virtual subsurface receivers. The SWV-RFs are the time series deconvolving the upgoing SV-wave component by the upgoing P-wave one. This method for ground surface records was originally introduced by Reading et al. (2003, GRL). Takenaka and Murakoshi (2010, AGU) proposed the SWV-RFs at the surface or subsurface station, which virtually move the seismic sensor at the surface or in the borehole down to the top of the basement layer and calculate the SWV-RFs at that location for suppressing the sedimentary layer effect. The SWV-RFs have a great advantage that the problem of unclearly seismic images beneath very thick sedimentary basin due to the records include strong effect of reverberation within the sedimentary layer can be overcome. Takenaka et al. (2014, AGU) applied the SWV-RFs to the teleseismic waveform records observed at borehole and ground surface stations and obtained clearly seismic images of Moho and subducted Philippine Sea plate beneath in Kyushu island, Japan. In this study, we applied the SWV-RFs from broadband seismic records of the F-net (NIED) and ETOS (JMA) to obtain the seismic structures in Ryukyu Arc, Japan. In this presentation, we will show the estimated seismic structure under each stations in the Ryukyu Arc, Japan. Acknowledgement: We have used Fnet data (NIED), ETOS data (JMA) and deep subsurface structure model by J-SHIS (NIED).

  19. Field testing for extreme universe space observatory aboard a super pressure balloon (EUSO-SPB): Logistics and first results

    Science.gov (United States)

    Cummings, Austin

    Extreme Universe Space Observatory aboard a Super Pressure Balloon (EUSO-SPB) is a prototype cosmic ray detector that will, for the first time, record cosmic rays from above. It is planned to fly for nearly 100 days at an altitude of 33 km, looking downward onto Earth's atmosphere, and measure the ultraviolet light emitted by ultra-high energy cosmic ray extensive air showers. It is the primary scientific payload aboard the 2017 NASA super pressure balloon flight launched from Wanaka, NZ. It was necessary to perform an end-to-end characterization of the instrument, as post test recovery is not guaranteed. A laser underflight study for EUSO-SPB is planned to occur to evaluate the assembled instrument's response to realistic optical tracks. In case of failure, it was necessary to conduct ground-to-ground testing, where laser test beams at "flight-like" distances through Earth's atmosphere would be provided. The Black Rock Mesa (BRM) Telescope Array (TA) test site in Delta, Utah was chosen as the location for the instrument field testing. The assembled and working EUSO-SPB instrument was transported using a ground loading, weather-sealed, air-suspension trailer and a custom "vibration-proof" dolly. During transportation, the maximum acceleration experienced by the instrument was 1.2 g's. Test beams were provided by a fixed energy, vertical laser at 21 km and by a steerable, variable energy, laser at 24 km. Hundreds of thousands of pulsed, UV laser shots were successfully recorded during the six nights of operation, with various energies, directions, and triggering methods. Energy sweeps were performed with a 45° tilted away laser at 24 km to determine the nominal energy threshold of EUSO-SPB in a balloon simulated geometry for two different lens configurations. First results show that the 2 lens configuration of EUSO-SPB was approximately twice as sensitive as the 3 lens configuration to laser light, with 50% energy thresholds of 1 mj and 2 mj, respectively. Cloud

  20. Mid-Pacific Ground-Truth Data For Validation of the CrIMSS Sensor Suite Aboard Suomi-NPP

    Science.gov (United States)

    Mollner, A. K.; Wessel, J.; Gaab, K. M.; Cardoza, D. M.; LaLumondiere, S. D.; Karuza, P.; Caponi, D.; Lotshaw, W. T.; Nalli, N. R.; Reale, T.; Divakarla, M.; Gambacorta, A.; Barnet, C.; Maddy, E. S.; Tan, C.; Xiong, X.; Porter, O.

    2013-12-01

    The Aerospace Transportable Lidar System 2 (ATLS-2) provides ground truth humidity and temperature data for the testing and evaluation of instruments aboard environmental satellites. The Aerospace ground-truth data consist of collocated state-of-the art lidar and radiosonde observations (RAOBs). The lidar system consists of a pulsed UV transmitter, 36-inch collection telescope, and detection channels for water Raman, nitrogen Raman, and Rayleigh/Mie scattering. All channels are separated into two altitude bins to improve the dynamic range of the system. Dedicated balloon-borne radiosondes are Vaisala RS-92, processed with the current version of the Digicora-III software. The synergy between the Raman lidar data and radiosonde data produce high accuracy, quality-controlled vertical profiles of humidity (0 - 20 km) and temperature (0 - 60 km). Starting in May 2012, The Aerospace Corporation has exercised ATLS-2 to collect dedicated ground truth data sets in support of calibration and validation (cal/val) efforts for the Cross-track Infrared and Microwave Sounding Suite (CrIMSS) aboard the Suomi-National Polar-orbiting Partnership (S-NPP) satellite. Data sets are collected from the Pacific Missile Range Facility (PMRF) on the west coast of Kauai and are timed to be coincident with S-NPP overpasses. The Aerospace PMRF datasets complement the ensemble of similar datasets collected from DOE Atmospheric Radiation Measurement (ARM) and NOAA Aerosols and Ocean Science Expedition (AEROSE) sites, which are compared to CrIMSS Environmental Data Records (EDRs) by the NOAA/NESDIS/STAR cal/val team for validation of algorithm performance and algorithm improvement. In addition to providing the only dedicated CrIMSS data in the mid-pacific, The Aerospace Corporation was the first site to provide ground truth data to the EDR cal/val team. As a result, ATLS-2 data sets served as the initial benchmarks for EDR performance testing. Details of the ATLS-2 system and data products as well

  1. Receiver function HV ratio: a new measurement for reducing non-uniqueness of receiver function waveform inversion

    Science.gov (United States)

    Chong, Jiajun; Chu, Risheng; Ni, Sidao; Meng, Qingjun; Guo, Aizhi

    2018-02-01

    It is known that a receiver function has relatively weak constraint on absolute seismic wave velocity, and that joint inversion of the receiver function with surface wave dispersion has been widely applied to reduce the trade-off of velocity with interface depth. However, some studies indicate that the receiver function itself is capable for determining the absolute shear-wave velocity. In this study, we propose to measure the receiver function HV ratio which takes advantage of the amplitude information of the receiver function to constrain the shear-wave velocity. Numerical analysis indicates that the receiver function HV ratio is sensitive to the average shear-wave velocity in the depth range it samples, and can help to reduce the non-uniqueness of receiver function waveform inversion. A joint inversion scheme has been developed, and both synthetic tests and real data application proved the feasibility of the joint inversion.

  2. Deep Sea Gazing: Making Ship-Based Research Aboard RV Falkor Relevant and Accessible

    Science.gov (United States)

    Wiener, C.; Zykov, V.; Miller, A.; Pace, L. J.; Ferrini, V. L.; Friedman, A.

    2016-02-01

    Schmidt Ocean Institute (SOI) is a private, non-profit operating foundation established to advance the understanding of the world's oceans through technological advancement, intelligent observation, and open sharing of information. Our research vessel Falkorprovides ship time to selected scientists and supports a wide range of scientific functions, including ROV operations with live streaming capabilities. Since 2013, SOI has live streamed 55 ROV dives in high definition and recorded them onto YouTube. This has totaled over 327 hours of video which received 1,450, 461 views in 2014. SOI is one of the only research programs that makes their entire dive series available online, creating a rich collection of video data sets. In doing this, we provide an opportunity for scientists to make new discoveries in the video data that may have been missed earlier. These data sets are also available to students, allowing them to engage with real data in the classroom. SOI's video collection is also being used in a newly developed video management system, Ocean Video Lab. Telepresence-enabled research is an important component of Falkor cruises, which is exemplified by several that were conducted in 2015. This presentation will share a few case studies including an image tagging citizen science project conducted through the Squidle interface in partnership with the Australian Center for Field Robotics. Using real-time image data collected in the Timor Sea, numerous shore-based citizens created seafloor image tags that could be used by a machine learning algorithms on Falkor's high performance computer (HPC) to accomplish habitat characterization. With the use of the HPC system real-time robot tracking, image tagging, and other outreach connections were made possible, allowing scientists on board to engage with the public and build their knowledge base. The above mentioned examples will be used to demonstrate the benefits of remote data analysis and participatory engagement in

  3. Diagnostic instrumentation aboard ISS: just-in-time training for non-physician crewmembers

    Science.gov (United States)

    Foale, C. Michael; Kaleri, Alexander Y.; Sargsyan, Ashot E.; Hamilton, Douglas R.; Melton, Shannon; Martin, David; Dulchavsky, Scott A.

    2005-01-01

    INTRODUCTION: The performance of complex tasks on the International Space Station (ISS) requires significant preflight crew training commitments and frequent skill and knowledge refreshment. This report documents a recently developed "just-in-time" training methodology, which integrates preflight hardware familiarization and procedure training with an on-orbit CD-ROM-based skill enhancement. This "just-in-time" concept was used to support real-time remote expert guidance to complete ultrasound examinations using the ISS Human Research Facility (HRF). METHODS: An American and Russian ISS crewmember received 2 h of "hands on" ultrasound training 8 mo prior to the on-orbit ultrasound exam. A CD-ROM-based Onboard Proficiency Enhancement (OPE) interactive multimedia program consisting of memory enhancing tutorials, and skill testing exercises, was completed by the crewmember 6 d prior to the on-orbit ultrasound exam. The crewmember was then remotely guided through a thoracic, vascular, and echocardiographic examination by ultrasound imaging experts. RESULTS: Results of the CD-ROM-based OPE session were used to modify the instructions during a complete 35-min real-time thoracic, cardiac, and carotid/jugular ultrasound study. Following commands from the ground-based expert, the crewmember acquired all target views and images without difficulty. The anatomical content and fidelity of ultrasound video were adequate for clinical decision making. CONCLUSIONS: Complex ultrasound experiments with expert guidance were performed with high accuracy following limited preflight training and multimedia based in-flight review, despite a 2-s communication latency. In-flight application of multimedia proficiency enhancement software, coupled with real-time remote expert guidance, facilitates the successful performance of ultrasound examinations on orbit and may have additional terrestrial and space applications.

  4. GNSS Receiver Identification Using Clock-Derived Metrics †

    Science.gov (United States)

    Gioia, Ciro; Cano Pons, Eduardo

    2017-01-01

    Falsifying Global Navigation Satellite System (GNSS) data with a simulator or with a fake receiver can have a significant economic or safety impact in many transportation applications where Position, Velocity and Time (PVT) are used to enforce a regulation. In this context, the authentication of the source of the PVT data (i.e., the GNSS receiver) is a requirement since data faking can become a serious threat. Receiver fingerprinting techniques represent possible countermeasures to verify the authenticity of a GNSS receiver and of its data. Herein, the potential of clock-derived metrics for GNSS receiver fingerprinting is investigated, and a filter approach is implemented for feature selection. Novel experimental results show that three intrinsic features are sufficient to identify a receiver. Moreover, the adopted technique is time effective as data blocks of about 40 min are sufficient to produce stable features for fingerprinting. PMID:28914760

  5. GNSS Receiver Identification Using Clock-Derived Metrics.

    Science.gov (United States)

    Borio, Daniele; Gioia, Ciro; Cano Pons, Eduardo; Baldini, Gianmarco

    2017-09-15

    Falsifying Global Navigation Satellite System (GNSS) data with a simulator or with a fake receiver can have a significant economic or safety impact in many transportation applications where Position, Velocity and Time (PVT) are used to enforce a regulation. In this context, the authentication of the source of the PVT data (i.e., the GNSS receiver) is a requirement since data faking can become a serious threat. Receiver fingerprinting techniques represent possible countermeasures to verify the authenticity of a GNSS receiver and of its data. Herein, the potential of clock-derived metrics for GNSS receiver fingerprinting is investigated, and a filter approach is implemented for feature selection. Novel experimental results show that three intrinsic features are sufficient to identify a receiver. Moreover, the adopted technique is time effective as data blocks of about 40 min are sufficient to produce stable features for fingerprinting.

  6. Solar advanced internal film receiver; Receptor avanzado de pelicular interna

    Energy Technology Data Exchange (ETDEWEB)

    Torre Cabezas, M. de la

    1990-07-01

    In a Solar Central Internal Film Receiver, the heat absorbing fluid (a molten nitrate salt) flows in a thin film down over the non illuminated side of an absorber panel. Since the molten salt working fluid is not contained in complicated tube manifolds, the receiver design is simples than a conventional tube type-receiver resulting in a lower cost and a more reliable receiver. The Internal Film Receiver can be considered as an alternative to the Direct Absorption Receiver, in the event that the current problems of the last one can not be solved. It also describes here the test facility which will be used for its solar test, and the test plans foreseen. (Author) 17 refs.

  7. BPSK Receiver Based on Recursive Adaptive Filter with Remodulation

    Directory of Open Access Journals (Sweden)

    N. Milosevic

    2011-12-01

    Full Text Available This paper proposes a new binary phase shift keying (BPSK signal receiver intended for reception under conditions of significant carrier frequency offsets. The recursive adaptive filter with least mean squares (LMS adaptation is used. The proposed receiver has a constant, defining the balance between the recursive and the nonrecursive part of the filter, whose proper choice allows a simple construction of the receiver. The correct choice of this parameter could result in unitary length of the filter. The proposed receiver has performance very close to the performance of the BPSK receiver with perfect frequency synchronization, in a wide range of frequency offsets (plus/minus quarter of the signal bandwidth. The results obtained by the software simulation are confirmed by the experimental results measured on the receiver realized with the universal software radio peripheral (USRP, with the baseband signal processing at personal computer (PC.

  8. Ways to rational management of accounts receivable at enterprises

    Directory of Open Access Journals (Sweden)

    Yevtushenko N. O.

    2015-05-01

    Full Text Available This article investigated the principal reasons of management problems an account receivable of enterprises. Credit politics of management is worked out by an account receivable of enterprises. Essence of the stages of construction of rational management an account receivable of enterprises is exposed. In the article are exposed the basic elements of control system for an account receivable such as mission, aims, strategy as politics of management. The basic stages of management politics are described for an account receivable of enterprises: analysis; organization of forming of principles of credit politics, terms of delivery of credit and procedure of collection of accounts receivable; planning of the use of modern forms of refunding, and similarly control.

  9. Improved Design and Implementation of Variational Bayesian Iterative Receivers

    Directory of Open Access Journals (Sweden)

    M. Modarresi

    2012-09-01

    Full Text Available It was recently shown that detection performance can be significantly improved if the statistics of channel estimation errors are available and properly used at the receiver. Although deriving the statistics of channel estimation errors is rather straightforward for pilot-only channel estimation methods, it is not the case for semi-blind receivers such as variational Bayesian (VB receivers. We have shown in a recent contribution that by a modified formulation of the VB formalism, one can reduce the impact of channel uncertainty on the decoder performance. In this paper, we propose different practical VB receiver implementation techniques that lead to further performance improvement. The adequacy of the proposed receiver design compared to classically-used VB receivers is demonstrated by simulations for orthogonal frequency-division multiplexing (OFDM systems.

  10. Performance Improvement of QPSK Signal Predetection EGC Diversity Receiver

    Directory of Open Access Journals (Sweden)

    B. Nikolic

    2012-09-01

    Full Text Available This paper proposes a modification of quadrature phase-shift-keying (QPSK signal diversity reception with predetection equal gain combiner (EGC. The EGC combining is realized by using the constant modulus algorithm (CMA. Carrier synchronization is performed by the phase locked loop (PLL. Comparative analysis of the modified and ordinary diversity receiver in the presence of carrier frequency offset in the additive white Gaussian noise (AWGN channel, as well as in Rician fading channel is shown. The proposed diversity receiver allows significant frequency offset compared to the diversity receiver that uses only PLL, and the error probability of the proposed receiver is very close to the error probability of the receiver with only PLL and zero frequency offset. The functionality of the proposed diversity receiver, as well as its properties is experimentally verified on a system based on universal software radio peripheral (USRP hardware. The performed comparison confirms the expected behavior of the system.

  11. Polarization mode dispersion effects on phase and polarization diversity receivers

    Science.gov (United States)

    Pratt, Thomas G.; Ingram, Mary Ann

    1992-12-01

    The objective of this paper is to examine the combined effects of weak phase noise and polarization mode dispersion (PMD) on a coherent receiver employing phase and polarization diversity reception. The receiver is assumed to be subjected to the following: transmitter and receiver polarization misalignment relative to the principal states of the optical fiber, phase noise, polarization mode dispersion, and shot noise. The receiver outputs are investigated for ASK demodulation using square-law and envelope detection. The results show that for the assumed receiver configuration, square law detection provides an output which is independent of PMD, phase noise, and polarization misalignment. Envelope detection results in a receiver output which is dependent on all of these parameters. Furthermore, when phase noise and PMD are simultaneously present, the resulting probability of bit error is no greater than the probability of bit error under worst-case operating conditions when polarization mode dispersion and phase noise are absent.

  12. Switched-RC Beamforming Receivers in Advanced CMOS

    OpenAIRE

    Soer, M.C.M.

    2012-01-01

    In consumer electronic devices, analog radio transmitters and receivers provide the wireless links between devices. These radios are mostly omni-directional, i.e. transmitters send their energy in all directions and receivers listen to signals from all directions. As a result, interference between devices and services is becoming an increasing problem as more wireless connectivity is added. In order to steer radio signals toward their destination and to receive from a specic direction, it is ...

  13. Guide to Repent and Receive Jesus Christ (in several languages)

    OpenAIRE

    Christianto, Victor

    2010-01-01

    This Guide to Repent and Receive Jesus Christ is dedicated to new believers in Christianity, in order that they can follow some steps in ordered manner, and by doing so feel completely guided in their pursuit of happiness. The seven steps to receive Jesus Christ: R - Recognize that you are sinners E - writE your sins and mistake in a paper P - Pray in order you will be forgiven, and receive Jesus Christ E - be Ensured that Jesus come to your heart ...

  14. Molecular Spectroscopy With a Compact 557-GHz Heterodyne Receiver

    OpenAIRE

    Neumaier, Philipp F.-X.; Richter, Heiko; Stake, Jan; Zhao, Huan; Tang, Aik-Yean; Drakinskiy, Vladimir; Sobis, Peter; Emrich, Anders; Hülsmann, Axel; Johansen, Tom K.; Bryllert, Tomas; Hanning, Johanna; Krozer, Viktor; Hübers, Heinz-Wilhelm

    2014-01-01

    We report on a heterodyne terahertz spectrometer based on a fully integrated 557-GHz receiver and a digital fast Fourier transform spectrometer. The receiver consists of a chain of multipliers and power amplifiers, followed by a heterostructure barrier varactor tripler that subharmonically pumps a membrane GaAs Schottky diode mixer. All sub-components are newly developed and optimized with regard to the overall receiver performance such as noise temperature, power consumption, weight and phys...

  15. GPS Receiver and Satellite DCB Estimation using Ionospheric TEC

    OpenAIRE

    Byung-Kyu Choi; Sung-Ki Cho; Sang-Jeong Lee

    2009-01-01

    We estimated the receiver and satellite differential code bias (DCB) based on the ionospheric total electron content (TEC) estimation method. The GPS network which has been operated by the Korea Astronomy and Space Science Institute (KASI) was designed to calculate TEC. The receiver and satellite DCB values were obtained from the weighted least square method with time interval for one hour. The results represented that the receiver DCB values are mostly varying within ±2 meter and are derived...

  16. Signal-processing theory for the TurboRogue receiver

    Science.gov (United States)

    Thomas, J. B.

    1995-01-01

    Signal-processing theory for the TurboRogue receiver is presented. The signal form is traced from its formation at the GPS satellite, to the receiver antenna, and then through the various stages of the receiver, including extraction of phase and delay. The analysis treats the effects of ionosphere, troposphere, signal quantization, receiver components, and system noise, covering processing in both the 'code mode' when the P code is not encrypted and in the 'P-codeless mode' when the P code is encrypted. As a possible future improvement to the current analog front end, an example of a highly digital front end is analyzed.

  17. Digital seismo-acoustic signal processing aboard a wireless sensor platform

    Science.gov (United States)

    Marcillo, O.; Johnson, J. B.; Lorincz, K.; Werner-Allen, G.; Welsh, M.

    2006-12-01

    We are developing a low power, low-cost wireless sensor array to conduct real-time signal processing of earthquakes at active volcanoes. The sensor array, which integrates data from both seismic and acoustic sensors, is based on Moteiv TMote Sky wireless sensor nodes (www.moteiv.com). The nodes feature a Texas Instruments MSP430 microcontroller, 48 Kbytes of program memory, 10 Kbytes of static RAM, 1 Mbyte of external flash memory, and a 2.4-GHz Chipcon CC2420 IEEE 802.15.4 radio. The TMote Sky is programmed in TinyOS. Basic signal processing occurs on an array of three peripheral sensor nodes. These nodes are tied into a dedicated GPS receiver node, which is focused on time synchronization, and a central communications node, which handles data integration and additional processing. The sensor nodes incorporate dual 12-bit digitizers sampling a seismic sensor and a pressure transducer at 100 samples per second. The wireless capabilities of the system allow flexible array geometry, with a maximum aperture of 200m. We have already developed the digital signal processing routines on board the Moteiv Tmote sensor nodes. The developed routines accomplish Real-time Seismic-Amplitude Measurement (RSAM), Seismic Spectral- Amplitude Measurement (SSAM), and a user-configured Short Term Averaging / Long Term Averaging (STA LTA ratio), which is used to calculate first arrivals. The processed data from individual nodes are transmitted back to a central node, where additional processing may be performed. Such processing will include back azimuth determination and other wave field analyses. Future on-board signal processing will focus on event characterization utilizing pattern recognition and spectral characterization. The processed data is intended as low bandwidth information which can be transmitted periodically and at low cost through satellite telemetry to a web server. The processing is limited by the computational capabilities (RAM, ROM) of the nodes. Nevertheless, we

  18. Sepsis outcomes in patients receiving statins prior to hospitalization for sepsis: comparison of in-hospital mortality rates between patients who received atorvastatin and those who received simvastatin.

    Science.gov (United States)

    Ouellette, Daniel R; Moscoso, Erics Espinoza; Corrales, Julio Pinto; Peters, Michael

    2015-01-01

    The purpose of this study is to compare the in-hospital mortality rates between septic patients receiving statins and those that did not prior to developing sepsis. We compared subgroups receiving atorvastatin and simvastatin because these two drugs differ in their pharmacologic properties. This study was a retrospective analysis of patients selected from an institutional data base of patients hospitalized with sepsis. The study patients were drawn from a data base of 1,961 hospitalized patients with sepsis and included patients who met selection criteria and who were studied for HMG-CoA reductase inhibitor (statin) use both prior to and during hospitalization. The in-hospital mortality rates of patients receiving statins and those that did not prior to developing sepsis were compared. In-hospital mortality rates of patient subgroups receiving atorvastatin and simvastatin were also compared. A multivariable analysis was conducted with in-hospital mortality as the outcome variable and with multiple risk factors to include atorvastatin and simvastatin use. The mortality rate for 359 patients receiving statins prior to hospitalization for sepsis was not significantly different than that for 1,302 patients who did not receive pre-hospital statins (26.5% versus 30.4%, p > 0.05). The mortality rate for 92 patients who had received atorvastatin prior to hospitalization was significantly less than that of 253 patients who received simvastatin (18.5% versus 30.0%, p = 0.032). The use of atorvastatin prior to sepsis was independently associated with lower in-hospital mortality in a multivariable analysis of sepsis risk factors (p = 0.021, OR = 0.455). Patients who received atorvastatin prior to hospitalization for sepsis and had statins continued in hospital had a very low mortality rate that was significantly less than that of those patients who never received statins (15.7% versus 30.8%, p = 0.007). Pre-hospital atorvastatin use was associated with

  19. The design and analysis of a modular microgravity test platform for use aboard the NASA KC-135 aircraft

    Science.gov (United States)

    Durand, Alain; Hertz, Roger; Mitchell, Darren; Rezkallah, Kamiel S.

    A microgravity platform to be used for housing experiments aboard the NASA KC-135 aircraft was designed using a modular construction approach. Two identical modules were designed to be used in three basic configurations: side by side, vertically stacked, or separately mounted. The levels within each module were adjustable and removable, providing yet another means by which the platform could be altered to suit the experiment being conducted. The frame was designed according to the strict strength and safety specifications set out by NASA. Additional design objectives stipulated that the frame be versatile, light weight, and accessible to the experiment operator. The ANSYS finite element stress analysis package was used to simulate the frame structure and its various components. Internal moments and forces were obtained from the finite element model and were later compared to the results from material performance tests. The results indicated that the platform could withstand the gravity levels experienced on the aircraft, including crash loads, with sufficient factors of safety.

  20. The nutritional status of astronauts is altered after long-term space flight aboard the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Zwart, Sara R.; Block, Gladys; Rice, Barbara L.; Davis-Street, Janis E.

    2005-01-01

    Defining optimal nutrient requirements is critical for ensuring crew health during long-duration space exploration missions. Data pertaining to such nutrient requirements are extremely limited. The primary goal of this study was to better understand nutritional changes that occur during long-duration space flight. We examined body composition, bone metabolism, hematology, general blood chemistry, and blood levels of selected vitamins and minerals in 11 astronauts before and after long-duration (128-195 d) space flight aboard the International Space Station. Dietary intake and limited biochemical measures were assessed during flight. Crew members consumed a mean of 80% of their recommended energy intake, and on landing day their body weight was less (P = 0.051) than before flight. Hematocrit, serum iron, ferritin saturation, and transferrin were decreased and serum ferritin was increased after flight (P superoxide dismutase was less after flight (P < 0.05), indicating increased oxidative damage. Despite vitamin D supplement use during flight, serum 25-hydroxycholecalciferol was decreased after flight (P < 0.01). Bone resorption was increased after flight, as indicated by several markers. Bone formation, assessed by several markers, did not consistently rise 1 d after landing. These data provide evidence that bone loss, compromised vitamin D status, and oxidative damage are among critical nutritional concerns for long-duration space travelers.

  1. Perspectives on chemical oceanography in the 21st century: Participants of the COME ABOARD Meeting examine aspects of the field in the context of 40 years of DISCO

    Science.gov (United States)

    Fassbender, Andrea J.; Palevsky, Hilary I.; Martz, Todd R.; Ingalls, Anitra E.; Gledhill, Martha; Fawcett, Sarah E.; Brandes, Jay; Aluwihare, Lihini; Anderson, Robert M.; Bender, Sara; Boyle, Ed; Bronk, Debbie; Buesseler, Ken; Burdige, David J.; Casciotti, Karen; Close, Hilary; Conte, Maureen; Cutter, Greg; Estapa, Meg; Fennel, Katja; Ferron, Sara; Glazer, Brian; Goni, Miguel; Grand, Max; Guay, Chris; Hatta, Mariko; Hayes, Chris; Horner, Tristan; Ingall, Ellery; Johnson, Kenneth G.; Juranek, Laurie; Knapp, Angela; Lam, Phoebe; Luther, George; Matrai, Paty; Nicholson, David; Paytan, Adina; Pellenbarg, Robert; Popendorf, Kim; Reddy, Christopher M.; Ruttenberg, Kathleen; Sabine, Chris; Sansone, Frank; Shaltout, Nayrah; Sikes, Liz; Sundquist, Eric T.; Valentine, David; Wang, Zhao (Aleck); Wilson, Sam; Barrett, Pamela; Behrens, Melanie; Belcher, Anna; Biermann, Lauren; Boiteau, Rene; Clarke, Jennifer; Collins, Jamie; Coppola, Alysha; Ebling, Alina M.; Garcia-Tigreros, Fenix; Goldman, Johanna; Guallart, Elisa F.; Haskell, William; Hurley, Sarah; Janssen, David; Johnson, Winn; Lennhartz, Sinikka; Liu, Shuting; Rahman, Shaily; Ray, Daisy; Sarkar, Amit; Steiner, Zvika; Widner, Brittany; Yang, Bo

    2017-01-01

    The questions that chemical oceanographers prioritize over the coming decades, and the methods we use to address these questions, will define our field's contribution to 21st century science. In recognition of this, the U.S. National Science Foundation and National Oceanic and Atmospheric Administration galvanized a community effort (the Chemical Oceanography MEeting: A BOttom-up Approach to Research Directions, or COME ABOARD) to synthesize bottom-up perspectives on selected areas of research in Chemical Oceanography. Representing only a small subset of the community, COME ABOARD participants did not attempt to identify targeted research directions for the field. Instead, we focused on how best to foster diverse research in Chemical Oceanography, placing emphasis on the following themes: strengthening our core chemical skillset; expanding our tools through collaboration with chemists, engineers, and computer scientists; considering new roles for large programs; enhancing interface research through interdisciplinary collaboration; and expanding ocean literacy by engaging with the public. For each theme, COME ABOARD participants reflected on the present state of Chemical Oceanography, where the community hopes to go and why, and actionable pathways to get there. A unifying concept among the discussions was that dissimilar funding structures and metrics of success may be required to accommodate the various levels of readiness and stages of knowledge development found throughout our community. In addition to the science, participants of the concurrent Dissertations Symposium in Chemical Oceanography (DISCO) XXV, a meeting of recent and forthcoming Ph.D. graduates in Chemical Oceanography, provided perspectives on how our field could show leadership in addressing long-standing diversity and early-career challenges that are pervasive throughout science. Here we summarize the COME ABOARD Meeting discussions, providing a synthesis of reflections and perspectives on the

  2. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1009 in the Philippine Sea from 2010-07-07 to 2010-07-19 (NODC Accession 0089639)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089639 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1009 in the Philippine Sea from 2010-07-07 to...

  3. Physical and underway data collected aboard the KILO MOANA during cruise KM0910 in the Philippine Sea and South China Sea (Nan Hai) from 2009-04-14 to 2009-05-04 (NODC Accession 0089592)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089592 includes physical and underway data collected aboard the KILO MOANA during cruise KM0910 in the Philippine Sea and South China Sea (Nan Hai)...

  4. Physical and profile data collected aboard the F.G. Walton Smith during cruise WS1207 in the Gulf of Mexico and North Atlantic Ocean from 2012-06-04 to 2012-06-08 (NCEI Accession 0129869)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129869 includes physical and profile data collected aboard the F.G. Walton Smith during cruise WS1207 in the Gulf of Mexico and North Atlantic Ocean...

  5. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1304 in the North Pacific Ocean from 2013-07-19 to 2013-07-20 (NCEI Accession 0135460)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0135460 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1304 in the North Pacific Ocean from 2013-07-19...

  6. Chemical and physical oceanographic profile data collected from CTD casts aboard the American Diver in the Gulf of Mexico on 2010-08-04 in response to the Deepwater Horizon oil spill event (NODC Accession 0069088)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical and physical oceanographic profile data were collected aboard the American Diver in the Gulf of Mexico on 2010-08-04 in response to the Deepwater Horizon...

  7. Chemical, physical, profile and underway oceanographic data collected aboard NOAA Ship GORDON GUNTER in the Gulf of Mexico from 2010-07-08 to 2010-07-16 in response to the Deepwater Horizon Oil Spill event (NCEI Accession 0070331)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical, physical, profile and underway oceanographic data were collected aboard NOAA Ship GORDON GUNTER in the Gulf of Mexico from 2010-07-08 to 2010-07-16 in...

  8. Physical, profile and underway data collected aboard the MELVILLE during cruise MV1210 in the North Pacific Ocean from 2012-07-28 to 2012-08-26 (NCEI Accession 0129827)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129827 includes physical, profile and underway data collected aboard the MELVILLE during cruise MV1210 in the North Pacific Ocean from 2012-07-28 to...

  9. Physical and underway data collected aboard the OCEANUS during cruise OC469-01 in the North Atlantic Ocean from 2010-10-02 to 2010-10-22 (NODC Accession 0104334)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104334 includes physical and underway data collected aboard the OCEANUS during cruise OC469-01 in the North Atlantic Ocean from 2010-10-02 to...

  10. Physical and underway data collected aboard the MELVILLE during cruise MGLN38MV in the Philippine Sea and South China Sea (Nan Hai) from 2008-05-04 to 2008-05-14 (NODC Accession 0098581)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098581 includes physical and underway data collected aboard the MELVILLE during cruise MGLN38MV in the Philippine Sea and South China Sea (Nan Hai)...

  11. Physical and underway data collected aboard the WECOMA during cruise W1010C in the Coastal Waters of SE Alaska and North Pacific Ocean from 2010-10-22 to 2010-11-01 (NODC Accession 0104380)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104380 includes physical and underway data collected aboard the WECOMA during cruise W1010C in the Coastal Waters of SE Alaska and North Pacific...

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Pacific Ocean from 2015-09-12 to 2015-09-30 (NCEI Accession 0142173)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0142173 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0909 in the East China Sea (Tung Hai) and Philippine Sea from 2009-08-23 to 2009-09-06 (NODC Accession 0089628)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089628 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0909 in the East China Sea (Tung Hai) and Philippine...

  14. Physical and underway data collected aboard the MELVILLE during cruise MV0910 in the North Pacific Ocean and Philippine Sea from 2009-10-31 to 2009-11-04 (NODC Accession 0089651)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089651 includes physical and underway data collected aboard the MELVILLE during cruise MV0910 in the North Pacific Ocean and Philippine Sea from...

  15. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1310 in the North Pacific Ocean from 2013-10-19 to 2013-10-20 (NCEI Accession 0138188)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138188 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1310 in the North Pacific Ocean from 2013-10-19...

  16. Physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1201 in the Indian Ocean from 2012-01-10 to 2012-02-12 (NCEI Accession 0129847)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129847 includes physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1201 in the Indian Ocean from 2012-01-10 to...

  17. Physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1114 in the Bay of Bengal, Indian Ocean and Timor Sea from 2011-08-29 to 2011-09-26 (NCEI Accession 0129844)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129844 includes physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1114 in the Bay of Bengal, Indian Ocean and...

  18. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean from 2014-08-10 to 2014-08-19 (NODC Accession 0121308)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0121308 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  19. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Rainier in the Gulf of Alaska from 2014-06-04 to 2014-06-20 (NCEI Accession 0141106)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0141106 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  20. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0901 in the South Pacific Ocean from 2009-01-12 to 2009-02-17 (NODC Accession 0089623)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089623 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0901 in the South Pacific Ocean from 2009-01-12 to...

  1. Physical and underway data collected aboard the NEW HORIZON during cruise NH1421 in the North Pacific Ocean from 2014-10-31 to 2014-11-03 (NCEI Accession 0132117)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132117 includes physical and underway data collected aboard the NEW HORIZON during cruise NH1421 in the North Pacific Ocean from 2014-10-31 to...

  2. Physical and profile data collected aboard the ROGER REVELLE during cruise RR1011 in the Philippine Sea and South China Sea (Nan Hai) from 2010-08-14 to 2010-09-11 (NCEI Accession 0134538)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0134538 includes physical and profile data collected aboard the ROGER REVELLE during cruise RR1011 in the Philippine Sea and South China Sea (Nan Hai)...

  3. Chemical, optical and other data collected aboard the MELVILLE during cruise MV0903 in the Philippine Sea, South China Sea (Nan Hai) and Sulu Sea from 2009-02-27 to 2009-03-21 (NODC Accession 0089605)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089605 includes chemical, optical, physical and underway data collected aboard the MELVILLE during cruise MV0903 in the Philippine Sea, South China...

  4. Profile data from CTD casts aboard the F/V Ocean Explorer in the Arctic Ocean and Beaufort Sea from 2008-08-06 to 2008-08-22 (NODC Accession 0001920)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This profile data aboard the F/V Ocean Explorer in the Arctic Ocean and Beaufort Sea from August 6, 2008 to August 22, 2008 was supported by the Minerals Management...

  5. Underway meteorological and oceanographic chemical and physical data collected aboard the R/V Celtic Explorer in the north Atlantic Ocean from June 15, 2006 to July 5, 2006 (NODC Accession 0084476)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0084476 includes underway meteorological and oceanographic chemical and physical data collected aboard the Celtic Explorer in North Atlantic Ocean...

  6. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1526 in the North Pacific Ocean from 2015-11-07 to 2015-11-08 (NCEI Accession 0150569)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150569 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1526 in the North Pacific Ocean from 2015-11-07...

  7. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1314 in the North Pacific Ocean from 2013-11-16 to 2013-11-17 (NCEI Accession 0137263)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137263 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1314 in the North Pacific Ocean from 2013-11-16...

  8. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1528 in the North Pacific Ocean from 2015-11-13 to 2015-11-15 (NCEI Accession 0150571)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150571 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1528 in the North Pacific Ocean from 2015-11-13...

  9. Physical and profile data collected aboard the NEW HORIZON during cruise NH1315 in the North Pacific Ocean from 2013-06-13 to 2013-06-28 (NCEI Accession 0132110)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0132110 includes physical and profile data collected aboard the NEW HORIZON during cruise NH1315 in the North Pacific Ocean from 2013-06-13 to...

  10. Physical, profile and underway data collected aboard the NEW HORIZON during cruise NH1410 in the North Pacific Ocean from 2014-05-10 to 2014-06-08 (NCEI Accession 0152500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0152500 includes physical, profile and underway data collected aboard the NEW HORIZON during cruise NH1410 in the North Pacific Ocean from 2014-05-10...

  11. Physical and underway data collected aboard the ATLANTIS during cruise AT15-56 in the Gulf of California from 2009-11-22 to 2009-12-06 (NODC Accession 0103912)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0103912 includes physical and underway data collected aboard the ATLANTIS during cruise AT15-56 in the Gulf of California from 2009-11-22 to...

  12. Physical and profile data collected aboard the NEW HORIZON during cruise NH1407 in the North Pacific Ocean from 2014-04-20 to 2014-04-21 (NCEI Accession 0138167)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0138167 includes physical and profile data collected aboard the NEW HORIZON during cruise NH1407 in the North Pacific Ocean from 2014-04-20 to...

  13. Physical and underway data collected aboard the OCEANUS during cruise OC1503B in the North Pacific Ocean from 2015-03-10 to 2015-03-14 (NCEI Accession 0150565)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150565 includes physical and underway data collected aboard the OCEANUS during cruise OC1503B in the North Pacific Ocean from 2015-03-10 to...

  14. Physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1204 in the North Pacific Ocean and Philippine Sea from 2012-02-01 to 2012-02-29 (NODC Accession 0104311)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104311 includes physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1204 in the North Pacific Ocean and Philippine...

  15. Chemical, physical, profile and other oceanographic data collected aboard the RYAN CHOUEST in the Gulf of Mexico from 2010-10-07 to 2010-10-17 in response to the Deepwater Horizon Oil Spill event (NODC Accession 0069356)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical, physical, profile, imagery, laboratory analysis and sediment analysis oceanographic data were collected aboard the RYAN CHOUEST in the Gulf of Mexico from...

  16. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1509 in the South Pacific Ocean from 2015-06-20 to 2015-06-30 (NCEI Accession 0145840)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145840 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1509 in the South Pacific Ocean from 2015-06-20 to...

  17. Oceanographic water temperature profiles from XBTs aboard multiple platforms as part of the GTSPP and SOT SOOP in the Southern Ocean and adjoining seas from 2016-02-10 to 2016-12-03 (NCEI Accession 0157632)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic water temperature profiles collected from XBTs aboard the platforms Maersk Jalan, Shengking, L'Astrolabe, and Siangtan in the South Pacific Ocean,...

  18. Physical and underway data collected aboard the ATLANTIS during cruise AT15-55 in the Gulf of California from 2009-11-05 to 2009-11-18 (NODC Accession 0103911)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0103911 includes physical and underway data collected aboard the ATLANTIS during cruise AT15-55 in the Gulf of California from 2009-11-05 to...

  19. Physical and underway data collected aboard the F. G. Walton Smith during cruise WS1010 in the Gulf of Mexico and North Atlantic Ocean from 2010-05-21 to 2010-06-11 (NODC Accession 0104382)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104382 includes physical and underway data collected aboard the F. G. Walton Smith during cruise WS1010 in the Gulf of Mexico and North Atlantic...

  20. Physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1205 in the North Pacific Ocean and Philippine Sea from 2012-03-03 to 2012-03-21 (NODC Accession 0104312)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104312 includes physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1205 in the North Pacific Ocean and Philippine...

  1. Physical and underway data collected aboard the MELVILLE during cruise MV1203 in the South Atlantic Ocean from 2012-02-11 to 2012-03-30 (NCEI Accession 0131907)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131907 includes physical and underway data collected aboard the MELVILLE during cruise MV1203 in the South Atlantic Ocean from 2012-02-11 to...

  2. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1102 in the South Atlantic Ocean and South Pacific Ocean from 2011-02-19 to 2011-03-14 (NCEI Accession 0130849)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130849 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1102 in the South Atlantic Ocean and South Pacific...

  3. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1104 in the South Pacific Ocean from 2011-03-23 to 2011-04-23 (NCEI Accession 0130851)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130851 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1104 in the South Pacific Ocean from 2011-03-23 to...

  4. Chemical, physical and underway data collected aboard the MELVILLE during cruise MV1112 in the Indian Ocean from 2011-11-03 to 2011-11-26 (NODC Accession 0117388)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117388 includes chemical, physical and underway data collected aboard the MELVILLE during cruise MV1112 in the Indian Ocean from 2011-11-03 to...

  5. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1219 in the North Pacific Ocean from 2012-10-11 to 2012-10-12 (NCEI Accession 0138185)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138185 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1219 in the North Pacific Ocean from 2012-10-11...

  6. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Nancy Foster in the Gulf of Mexico and North Atlantic Ocean from 2016-03-28 to 2016-04-01 (NCEI Accession 0150694)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150694 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  7. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2013-03-27 to 2013-06-14 (NODC Accession 0122515)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0122515 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  8. Physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1109 in the Gulf of Alaska and North Pacific Ocean from 2011-06-06 to 2011-06-26 (NODC Accession 0104306)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104306 includes physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1109 in the Gulf of Alaska and North Pacific...

  9. Physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1111 in the Bering Sea from 2011-08-07 to 2011-09-04 (NODC Accession 0104307)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104307 includes physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1111 in the Bering Sea from 2011-08-07 to...

  10. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Gulf of Alaska, North Pacific Ocean and South Pacific Ocean from 2015-04-10 to 2015-06-24 (NCEI Accession 0129524)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129524 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  11. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean from 2016-03-29 to 2016-04-24 (NCEI Accession 0155759)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155759 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  12. Chemical, optical and physical data collected aboard the OCEANUS during cruise OC415-04 in the North Atlantic Ocean from 2005-07-19 to 2005-09-15 (NCEI Accession 0155492)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155492 includes chemical, optical and physical data collected aboard the OCEANUS during cruise OC415-04 in the North Atlantic Ocean from 2005-07-19...

  13. Biological, chemical and other data collected aboard the THOMAS G. THOMPSON during cruise TN256 in the Coastal Waters of SE Alaska from 2010-10-23 to 2010-11-03 (NODC Accession 0104361)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104361 includes biological, chemical, optical, physical and underway data collected aboard the THOMAS G. THOMPSON during cruise TN256 in the Coastal...

  14. Biological, chemical and other data collected aboard the THOMAS G. THOMPSON during cruise TN244 in the Coastal Waters of SE Alaska from 2009-12-05 to 2009-12-08 (NODC Accession 0117395)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0117395 includes biological, chemical, optical and physical data collected aboard the THOMAS G. THOMPSON during cruise TN244 in the Coastal Waters of...

  15. Biological, chemical and other data collected aboard the THOMAS G. THOMPSON during cruise TN264 in the Coastal Waters of SE Alaska and North Pacific Ocean from 2011-05-21 to 2011-05-24 (NODC Accession 0117418)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0117418 includes biological, chemical, optical and physical data collected aboard the THOMAS G. THOMPSON during cruise TN264 in the Coastal Waters of...

  16. Biological, chemical and other data collected aboard the OCEANUS during cruise OC404-01 in the North Atlantic Ocean from 2004-06-11 to 2004-07-03 (NODC Accession 0117389)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0117389 includes biological, chemical, optical and physical data collected aboard the OCEANUS during cruise OC404-01 in the North Atlantic Ocean from...

  17. Biological, chemical and other data collected aboard the MELVILLE during cruise MV0911 in the Coral Sea, Indian Ocean and others from 2009-11-21 to 2010-01-03 (NODC Accession 0089671)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089671 includes biological, chemical, optical, physical and underway data collected aboard the MELVILLE during cruise MV0911 in the Coral Sea, Indian...

  18. Chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN282 in the Coastal Waters of SE Alaska and North Pacific Ocean from 2012-03-11 to 2012-07-06 (NODC Accession 0104374)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0104374 includes chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN282 in the Coastal Waters of SE Alaska and...

  19. Chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN268 in the Coastal Waters of SE Alaska and North Pacific Ocean from 2011-08-11 to 2011-09-01 (NODC Accession 0104367)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0104367 includes chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN268 in the Coastal Waters of SE Alaska and...

  20. Chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN255 in the Coastal Waters of SE Alaska and North Pacific Ocean from 2010-10-16 to 2010-10-20 (NODC Accession 0104360)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0104360 includes chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN255 in the Coastal Waters of SE Alaska and...