Science.gov

Sample records for air navigational aid

  1. Development of visual-display aid to air navigation

    NASA Technical Reports Server (NTRS)

    Matcovich, T. J.

    1973-01-01

    The developments are discussed in the design of a liquid-crystal, visual display, air navigation aid, which uses two VOR signals to locate the aircraft. The system concepts, liquid crystal materials, stability tests, and the electronic system are described. It is concluded that a navigational aid of this type is technically feasible, but not at the projected low cost.

  2. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  3. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  4. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  5. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  6. 47 CFR 87.395 - Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... and Air Navigation Aids (Short Title: SCATANA). 87.395 Section 87.395 Telecommunication FEDERAL... Communications § 87.395 Plan for the Security Control of Air Traffic and Air Navigation Aids (Short Title: SCATANA). (a) The Plan for the Security Control of Air Traffic and Air Navigation Aids (SCATANA)...

  7. Investigation of air transportation technology at Ohio University, 1980. [general aviation aircraft and navigation aids

    NASA Technical Reports Server (NTRS)

    Mcfarland, R. H.

    1981-01-01

    Specific configurations of first and second order all digital phase locked loops were analyzed for both ideal and additive gaussian noise inputs. In addition, a design for a hardware digital phase locked loop capable of either first or second order operation was evaluated along with appropriate experimental data obtained from testing of the hardware loop. All parameters chosen for the analysis and the design of the digital phase locked loop were consistent with an application to an Omega navigation receiver although neither the analysis nor the design are limited to this application. For all cases tested, the experimental data showed close agreement with the analytical results indicating that the Markov chain model for first and second order digital phase locked loops are valid.

  8. 33 CFR 66.10-15 - Aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Aids to navigation. 66.10-15 Section 66.10-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-15 Aids to navigation....

  9. 33 CFR 66.10-15 - Aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Aids to navigation. 66.10-15 Section 66.10-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-15 Aids to navigation....

  10. 33 CFR 66.10-15 - Aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Aids to navigation. 66.10-15 Section 66.10-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-15 Aids to navigation....

  11. 33 CFR 66.10-15 - Aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Aids to navigation. 66.10-15 Section 66.10-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-15 Aids to navigation....

  12. 33 CFR 66.10-15 - Aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Aids to navigation. 66.10-15 Section 66.10-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-15 Aids to navigation....

  13. 33 CFR 401.54 - Interference with navigation aids.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b)...

  14. 33 CFR 401.54 - Interference with navigation aids.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b)...

  15. 33 CFR 67.35-10 - Private aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications §...

  16. 33 CFR 401.54 - Interference with navigation aids.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b)...

  17. 33 CFR 67.35-10 - Private aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications §...

  18. 33 CFR 67.35-10 - Private aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications §...

  19. 33 CFR 67.35-10 - Private aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications §...

  20. 33 CFR 67.35-10 - Private aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications §...

  1. 33 CFR 401.54 - Interference with navigation aids.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b)...

  2. 33 CFR 401.54 - Interference with navigation aids.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b)...

  3. Fully Self-Contained Vision-Aided Navigation and Landing of a Micro Air Vehicle Independent from External Sensor Inputs

    NASA Technical Reports Server (NTRS)

    Brockers, Roland; Susca, Sara; Zhu, David; Matthies, Larry

    2012-01-01

    Direct-lift micro air vehicles have important applications in reconnaissance. In order to conduct persistent surveillance in urban environments, it is essential that these systems can perform autonomous landing maneuvers on elevated surfaces that provide high vantage points without the help of any external sensor and with a fully contained on-board software solution. In this paper, we present a micro air vehicle that uses vision feedback from a single down looking camera to navigate autonomously and detect an elevated landing platform as a surrogate for a roof top. Our method requires no special preparation (labels or markers) of the landing location. Rather, leveraging the planar character of urban structure, the landing platform detection system uses a planar homography decomposition to detect landing targets and produce approach waypoints for autonomous landing. The vehicle control algorithm uses a Kalman filter based approach for pose estimation to fuse visual SLAM (PTAM) position estimates with IMU data to correct for high latency SLAM inputs and to increase the position estimate update rate in order to improve control stability. Scale recovery is achieved using inputs from a sonar altimeter. In experimental runs, we demonstrate a real-time implementation running on-board a micro aerial vehicle that is fully self-contained and independent from any external sensor information. With this method, the vehicle is able to search autonomously for a landing location and perform precision landing maneuvers on the detected targets.

  4. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Navigation lights, aids to... ADMINISTRATIVE PROCEDURE § 209.325 Navigation lights, aids to navigation, navigation charts, and related data... procedure to be used by all Corps of Engineers installations and activities in connection with aids...

  5. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Navigation lights, aids to... ADMINISTRATIVE PROCEDURE § 209.325 Navigation lights, aids to navigation, navigation charts, and related data... procedure to be used by all Corps of Engineers installations and activities in connection with aids...

  6. 33 CFR 100.45 - Establishment of aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  7. 33 CFR 100.45 - Establishment of aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  8. 33 CFR 100.45 - Establishment of aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  9. 33 CFR 100.45 - Establishment of aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  10. 33 CFR 100.45 - Establishment of aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  11. Crew-Aided Autonomous Navigation

    NASA Technical Reports Server (NTRS)

    Holt, Greg N.

    2015-01-01

    A sextant provides manual capability to perform star/planet-limb sightings and offers a cheap, simple, robust backup navigation source for exploration missions independent from the ground. Sextant sightings from spacecraft were first exercised in Gemini and flew as the lost-communication backup for all Apollo missions. This study characterized error sources of navigation-grade sextants for feasibility of taking star and planetary limb sightings from inside a spacecraft. A series of similar studies was performed in the early/mid-1960s in preparation for Apollo missions. This study modernized and updated those findings in addition to showing feasibility using Linear Covariance analysis techniques. The human eyeball is a remarkable piece of optical equipment and provides many advantages over camera-based systems, including dynamic range and detail resolution. This technique utilizes those advantages and provides important autonomy to the crew in the event of lost communication with the ground. It can also provide confidence and verification of low-TRL automated onboard systems. The technique is extremely flexible and is not dependent on any particular vehicle type. The investigation involved procuring navigation-grade sextants and characterizing their performance under a variety of conditions encountered in exploration missions. The JSC optical sensor lab and Orion mockup were the primary testing locations. For the accuracy assessment, a group of test subjects took sextant readings on calibrated targets while instrument/operator precision was measured. The study demonstrated repeatability of star/planet-limb sightings with bias and standard deviation around 10 arcseconds, then used high-fidelity simulations to verify those accuracy levels met the needs for targeting mid-course maneuvers in preparation for Earth reen.

  12. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids...

  13. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids...

  14. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids...

  15. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids...

  16. 33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids...

  17. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained...

  18. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained...

  19. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained...

  20. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained...

  1. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained...

  2. 33 CFR 66.05-35 - Private aids to navigation other than State owned.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality...

  3. 33 CFR 66.05-35 - Private aids to navigation other than State owned.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality...

  4. 33 CFR 66.05-35 - Private aids to navigation other than State owned.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality...

  5. 33 CFR 66.05-25 - Change and modification of State aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines...

  6. 33 CFR 66.05-25 - Change and modification of State aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines...

  7. 33 CFR 66.05-25 - Change and modification of State aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines...

  8. 33 CFR 66.05-35 - Private aids to navigation other than State owned.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality...

  9. 33 CFR 66.05-35 - Private aids to navigation other than State owned.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality...

  10. 33 CFR 66.05-25 - Change and modification of State aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines...

  11. 33 CFR 66.05-25 - Change and modification of State aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines...

  12. Cognitive Costs of Navigation Aids in Hypermedia Learning

    ERIC Educational Resources Information Center

    Waniek, Jacqueline; Ewald, Karolin

    2008-01-01

    This study examines the cognitive costs of navigation aids in a hypermedia learning task. In a 2(navigable vs. non-navigable) x 2(map vs. content list) experimental design cognitive requirements were measured by users' eye movement data. Additionally, data from users' navigation operations, knowledge acquisition, and subjective evaluation of the…

  13. 33 CFR 149.505 - What are the general requirements for aids to navigation?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter,...

  14. 33 CFR 149.505 - What are the general requirements for aids to navigation?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter,...

  15. 33 CFR 149.505 - What are the general requirements for aids to navigation?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter,...

  16. 33 CFR 149.505 - What are the general requirements for aids to navigation?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter,...

  17. 33 CFR 149.505 - What are the general requirements for aids to navigation?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter,...

  18. Vision aided inertial navigation system augmented with a coded aperture

    NASA Astrophysics Data System (ADS)

    Morrison, Jamie R.

    Navigation through a three-dimensional indoor environment is a formidable challenge for an autonomous micro air vehicle. A main obstacle to indoor navigation is maintaining a robust navigation solution (i.e. air vehicle position and attitude estimates) given the inadequate access to satellite positioning information. A MEMS (micro-electro-mechanical system) based inertial navigation system provides a small, power efficient means of maintaining a vehicle navigation solution; however, unmitigated error propagation from relatively noisy MEMS sensors results in the loss of a usable navigation solution over a short period of time. Several navigation systems use camera imagery to diminish error propagation by measuring the direction to features in the environment. Changes in feature direction provide information regarding direction for vehicle movement, but not the scale of movement. Movement scale information is contained in the depth to the features. Depth-from-defocus is a classic technique proposed to derive depth from a single image that involves analysis of the blur inherent in a scene with a narrow depth of field. A challenge to this method is distinguishing blurriness caused by the focal blur from blurriness inherent to the observed scene. In 2007, MIT's Computer Science and Artificial Intelligence Laboratory demonstrated replacing the traditional rounded aperture with a coded aperture to produce a complex blur pattern that is more easily distinguished from the scene. A key to measuring depth using a coded aperture then is to correctly match the blur pattern in a region of the scene with a previously determined set of blur patterns for known depths. As the depth increases from the focal plane of the camera, the observable change in the blur pattern for small changes in depth is generally reduced. Consequently, as the depth of a feature to be measured using a depth-from-defocus technique increases, the measurement performance decreases. However, a Fresnel zone

  19. Space shuttle navigation analysis. Volume 1: GPS aided navigation

    NASA Technical Reports Server (NTRS)

    Matchett, G. A.; Vogel, M. A.; Macdonald, T. J.

    1980-01-01

    Analytical studies related to space shuttle navigation are presented. Studies related to the addition of NAVSTAR Global Positioning System user equipment to the shuttle avionics suite are presented. The GPS studies center about navigation accuracy covariance analyses for both developmental and operational phases of GPS, as well as for various orbiter mission phases.

  20. The attribution of success when using navigation aids

    PubMed Central

    Brown, Michael; Houghton, Robert; Sharples, Sarah; Morley, Jeremy

    2015-01-01

    Attitudes towards geographic information technology is a seldom explored research area that can be explained with reference to established theories of attribution. This article reports on a study of how the attribution of success and failure in pedestrian navigation varies with level of automation, degree of success and locus of control. A total of 113 participants took part in a survey exploring reflections on personal experiences and vignettes describing fictional navigation experiences. A complex relationship was discovered in which success tends to be attributed to skill and failure to the navigation aid when participants describe their own experiences. A reversed pattern of results was found when discussing the navigation of others. It was also found that navigation success and failure are associated with personal skill to a greater extent when using paper maps, as compared with web-based routing engines or satellite navigation systems. Practitioner Summary: This article explores the influences on the attribution of success and failure when using navigation aids. A survey was performed exploring interpretations of navigation experiences. Level of success, self or other as navigator and type of navigation aid used are all found to influence the attribution of outcomes to internal or external factors. PMID:25384842

  1. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of...

  2. 33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a)...

  3. 33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a)...

  4. 33 CFR 150.715 - What are the requirements for lights used as aids to navigation?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... lights used as aids to navigation? 150.715 Section 150.715 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.715 What are the requirements for lights used as aids to navigation? (a) Each light under part...

  5. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of...

  6. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of...

  7. 33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a)...

  8. 33 CFR 150.715 - What are the requirements for lights used as aids to navigation?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... lights used as aids to navigation? 150.715 Section 150.715 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.715 What are the requirements for lights used as aids to navigation? (a) Each light under part...

  9. 33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a)...

  10. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of...

  11. 33 CFR 150.715 - What are the requirements for lights used as aids to navigation?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... lights used as aids to navigation? 150.715 Section 150.715 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.715 What are the requirements for lights used as aids to navigation? (a) Each light under part...

  12. 33 CFR 150.715 - What are the requirements for lights used as aids to navigation?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... lights used as aids to navigation? 150.715 Section 150.715 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.715 What are the requirements for lights used as aids to navigation? (a) Each light under part...

  13. 33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a)...

  14. 33 CFR 150.715 - What are the requirements for lights used as aids to navigation?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... lights used as aids to navigation? 150.715 Section 150.715 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.715 What are the requirements for lights used as aids to navigation? (a) Each light under part...

  15. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of...

  16. 33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids...

  17. 33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids...

  18. 33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids...

  19. 33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids...

  20. 33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids...

  1. 33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions,...

  2. 33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions,...

  3. 33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions,...

  4. 33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions,...

  5. 33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions,...

  6. Crew-Aided Autonomous Navigation Project

    NASA Technical Reports Server (NTRS)

    Holt, Greg

    2015-01-01

    Manual capability to perform star/planet-limb sightings provides a cheap, simple, and robust backup navigation source for exploration missions independent from the ground. Sextant sightings from spacecraft were first exercised in Gemini and flew as the loss-of-communications backup for all Apollo missions. This study seeks to procure and characterize error sources of navigation-grade sextants for feasibility of taking star and planetary limb sightings from inside a spacecraft. A series of similar studies was performed in the early/mid-1960s in preparation for Apollo missions, and one goal of this study is to modernize and update those findings. This technique has the potential to deliver significant risk mitigation, validation, and backup to more complex low-TRL automated systems under development involving cameras.

  7. 47 CFR 22.365 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Antenna structures; air navigation safety. 22... Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become a hazard to air navigation. In general, antenna structure owners...

  8. 47 CFR 22.365 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Antenna structures; air navigation safety. 22... Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become a hazard to air navigation. In general, antenna structure owners...

  9. 47 CFR 22.365 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Antenna structures; air navigation safety. 22... Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become a hazard to air navigation. In general, antenna structure owners...

  10. 47 CFR 22.365 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Antenna structures; air navigation safety. 22... Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become a hazard to air navigation. In general, antenna structure owners...

  11. 47 CFR 22.365 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Antenna structures; air navigation safety. 22... Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become a hazard to air navigation. In general, antenna structure owners...

  12. 43 CFR 2651.6 - Airport and air navigation facilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Airport and air navigation facilities... Village Selections § 2651.6 Airport and air navigation facilities. (a) Every airport and air navigation.... (b) The surface of all other lands of existing airport sites, airway beacons, or other...

  13. 43 CFR 2651.6 - Airport and air navigation facilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Airport and air navigation facilities... Village Selections § 2651.6 Airport and air navigation facilities. (a) Every airport and air navigation.... (b) The surface of all other lands of existing airport sites, airway beacons, or other...

  14. 43 CFR 2651.6 - Airport and air navigation facilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Airport and air navigation facilities... Village Selections § 2651.6 Airport and air navigation facilities. (a) Every airport and air navigation.... (b) The surface of all other lands of existing airport sites, airway beacons, or other...

  15. 43 CFR 2651.6 - Airport and air navigation facilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Airport and air navigation facilities... Village Selections § 2651.6 Airport and air navigation facilities. (a) Every airport and air navigation.... (b) The surface of all other lands of existing airport sites, airway beacons, or other...

  16. Navigating the Complex World of Financial Aid

    ERIC Educational Resources Information Center

    Baum, Sandy

    2010-01-01

    The financial-aid policies and practices of colleges and universities have made too many headlines in recent times to remain the domain of technical experts. Boards of trustees, like other constituencies that are responsible for the health and well-being of postsecondary institutions, should be asking how issues being raised about student…

  17. 33 CFR 150.810 - Reporting a problem with an aid to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Reporting a problem with an aid....810 Reporting a problem with an aid to navigation. (a) Any problem affecting the operation or characteristics of a navigation aid at the deepwater port must be reported to the District Commander by...

  18. Optic flow aided navigation and 3D scene reconstruction

    NASA Astrophysics Data System (ADS)

    Rollason, Malcolm

    2013-10-01

    An important enabler for low cost airborne systems is the ability to exploit low cost inertial instruments. An Inertial Navigation System (INS) can provide a navigation solution, when GPS is denied, by integrating measurements from inertial sensors. However, the gyrometer and accelerometer biases of low cost inertial sensors cause compound errors in the integrated navigation solution. This paper describes experiments to establish whether (and to what extent) the navigation solution can be aided by fusing measurements from an on-board video camera with measurements from the inertial sensors. The primary aim of the work was to establish whether optic flow aided navigation is beneficial even when the 3D structure within the observed scene is unknown. A further aim was to investigate whether an INS can help to infer 3D scene content from video. Experiments with both real and synthetic data have been conducted. Real data was collected using an AR Parrot quadrotor. Empirical results illustrate that optic flow provides a useful aid to navigation even when the 3D structure of the observed scene is not known. With optic flow aiding of the INS, the computed trajectory is consistent with the true camera motion, whereas the unaided INS yields a rapidly increasing position error (the data represents ~40 seconds, after which the unaided INS is ~50 metres in error and has passed through the ground). The results of the Monte Carlo simulation concur with the empirical result. Position errors, which grow as a quadratic function of time when unaided, are substantially checked by the availability of optic flow measurements.

  19. A research on SLAM aided INS/GPS navigation system

    NASA Astrophysics Data System (ADS)

    Cao, Menglong; Cui, Pingyuan

    2007-11-01

    Simultaneous Localization and Mapping (SLAM) aided INS/GPS navigation system is a landmark based terrain aided autonomous integrated system that has the capability for online map building and simultaneously utilizing the generated map to bind the errors in the Inertial Navigation System (INS) when GPS is not available. If GPS information is available, the SLAM integrated system builds a landmark-based map using an INS/GPS solution. If GPS is not available, the previously newly generated map is used to constrain the INS errors. The SLAM augmented INS/GPS system shows two capabilities of landmark tracking and mapping using GPS information and more importantly, aiding the INS under GPS denied situation. The validity of the proposed method is demonstrated by computer simulation.

  20. Computer Navigation-aided Resection of Sacral Chordomas

    PubMed Central

    Yang, Yong-Kun; Chan, Chung-Ming; Zhang, Qing; Xu, Hai-Rong; Niu, Xiao-Hui

    2016-01-01

    Background: Resection of sacral chordomas is challenging. The anatomy is complex, and there are often no bony landmarks to guide the resection. Achieving adequate surgical margins is, therefore, difficult, and the recurrence rate is high. Use of computer navigation may allow optimal preoperative planning and improve precision in tumor resection. The purpose of this study was to evaluate the safety and feasibility of computer navigation-aided resection of sacral chordomas. Methods: Between 2007 and 2013, a total of 26 patients with sacral chordoma underwent computer navigation-aided surgery were included and followed for a minimum of 18 months. There were 21 primary cases and 5 recurrent cases, with a mean age of 55.8 years old (range: 35–84 years old). Tumors were located above the level of the S3 neural foramen in 23 patients and below the level of the S3 neural foramen in 3 patients. Three-dimensional images were reconstructed with a computed tomography-based navigation system combined with the magnetic resonance images using the navigation software. Tumors were resected via a posterior approach assisted by the computer navigation. Mean follow-up was 38.6 months (range: 18–84 months). Results: Mean operative time was 307 min. Mean intraoperative blood loss was 3065 ml. For computer navigation, the mean registration deviation during surgery was 1.7 mm. There were 18 wide resections, 4 marginal resections, and 4 intralesional resections. All patients were alive at the final follow-up, with 2 (7.7%) exhibiting tumor recurrence. The other 24 patients were tumor-free. The mean Musculoskeletal Tumor Society Score was 27.3 (range: 19–30). Conclusions: Computer-assisted navigation can be safely applied to the resection of the sacral chordomas, allowing execution of preoperative plans, and achieving good oncological outcomes. Nevertheless, this needs to be accomplished by surgeons with adequate experience and skill. PMID:26830986

  1. Traditional Aids to Navigation: The Next 25 Years

    NASA Astrophysics Data System (ADS)

    Turner, Neil Macdonald

    The authors of this paper are the three General Lighthouse Authorities (GLAs) of the United Kingdom and the Republic of Ireland. It was presented on their behalf at the RIN-96 conference by Captain Turner. The paper gives a brief overview of the policy of the GLAs (i.e. the Corporation of Trinity House, the Northern Lighthouse Board and the Commissioners of Irish Lights) regarding the provision of an aids to navigation service with emphasis on the future prospects of traditional aids to navigation over the next 25 years. The three GLAs have recently carried out a consultation exercise on marine aids to navigation into the 21st century. The results of this consultation exercise are discussed. It should be noted that, for clarity, the General Lighthouse Authorities (GLAs) refer to the systems that they provide as (AtoN), to differentiate their provision from the equipment carried on board ships for navigational purposes which are referred to by the GLAs as . This paper therefore in the main deals with AtoN.The coastlines within the GLAs' areas of responsibility rank with the most heavily trafficked and dangerous in the world. The coastlines vary from isolated rocks and the steep, Atlantic coastline, to the low-lying relatively featureless coastline of south-east England, off which are shifting sandbanks and channels. The tidal range in GLA waters is significant and tidal streams can reach 10 knots or more in a number of places.

  2. Gravity gradiometer aided inertial navigation within non-GNSS environments

    NASA Astrophysics Data System (ADS)

    Richeson, Justin A.

    Gravity gradiometer aiding of a strapdown inertial navigation system (INS) in the event of Global Navigation Satellite System (GNSS) signal loss, or as a complement to an INS/GNSS system, is proposed. Gravity gradiometry is ideal for covert military applications where a self contained, passive, spoof-free aid is desirable, and for space navigation near planetary bodies and moons where GNSS is unavailable. This dissertation provides the first comprehensive discussion on gravity gradiometry fundamentals, map modeling, and regional and altitude effects on the gravitational gradient signal for use as a navigation aid. A thorough methodology to implement strapdown and stabilized gravity gradiometer instruments (GGIs) into an autonomous extended Kalman filter is also presented in the open literature for the first time. Lastly, a brief discussion on extraterrestrial navigation using gravity gradiometry is given. To quantify the potential performance for future gravity gradiometer instruments as an INS aid, extensive Monte Carlo simulations of a hypersonic scramjet cruise missile were performed. The results for the 1000 km range mission indicate that GGI updates significantly improve the navigation accuracy of the autonomous INS. The sensitivities of the system to variations in inertial measurement unit (IMU) quality, gravity field variation, GGI noise, update rate, and type are also investigated along with a baseline INS/Global Positioning System (GPS). Given emerging technologies that have the potential to drastically decrease gradiometer noise levels, a hypothetical future grade gravity gradiometer aided INS is shown to bound root-mean-square (RMS) position errors at 0.336 m, velocity errors at 0.0069 m/s, and attitude errors at 0.00977°, which is comparable to the nominal INS/GPS system with 10 sec updates. The performance of two subsonic cases is also investigated and produced impressive passive navigation accuracy. A commercial aircraft simulation using a future

  3. AFTI/SITAN (Advanced Fighter Technology Integration/Sandia Inertial Terrain-Aided Navigation) final report

    SciTech Connect

    Fellerhoff, J.R.

    1988-11-01

    Sandia Inertial Terrain-Aided Navigation (SITAN) provides continuous position fixes to an inertial navigation system (INS) by real-time comparison of radar altimeter ground clearance measurements with stored digital terrain elevation data (DTED). This is accomplished by using an extended Kalman filter algorithm to estimate the errors in the reference trajectory provided by an INS. In this report, Sandia National Laboratories documents the results of a reimbursable effort funded by the Air Force Wright Aeronautical Laboratories (AFWAL) Avionics Laboratory to flight test SITAN as implemented onboard the Advanced Fighter Technology Integration (AFTI)F-16. 5 refs., 101 figs., 1 tab.

  4. 46 CFR 122.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Report of accident to aid to navigation. 122.230 Section... Marine Casualties and Voyage Records § 122.230 Report of accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under the jurisdiction of the Coast Guard, or is...

  5. 46 CFR 185.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Report of accident to aid to navigation. 185.230 Section 185.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS... aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  6. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Report of accident to aid to navigation. 4.05-20 Section 4.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC... accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  7. 46 CFR 122.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Report of accident to aid to navigation. 122.230 Section... Marine Casualties and Voyage Records § 122.230 Report of accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under the jurisdiction of the Coast Guard, or is...

  8. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Report of accident to aid to navigation. 4.05-20 Section 4.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC... accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  9. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Report of accident to aid to navigation. 4.05-20 Section 4.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC... accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  10. 46 CFR 122.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Report of accident to aid to navigation. 122.230 Section... Marine Casualties and Voyage Records § 122.230 Report of accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under the jurisdiction of the Coast Guard, or is...

  11. 46 CFR 122.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Report of accident to aid to navigation. 122.230 Section... Marine Casualties and Voyage Records § 122.230 Report of accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under the jurisdiction of the Coast Guard, or is...

  12. 46 CFR 122.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Report of accident to aid to navigation. 122.230 Section... Marine Casualties and Voyage Records § 122.230 Report of accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under the jurisdiction of the Coast Guard, or is...

  13. 46 CFR 185.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Report of accident to aid to navigation. 185.230 Section 185.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS... aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  14. 46 CFR 185.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Report of accident to aid to navigation. 185.230 Section 185.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS... aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  15. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Report of accident to aid to navigation. 4.05-20 Section 4.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC... accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  16. 46 CFR 185.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Report of accident to aid to navigation. 185.230 Section 185.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS... aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  17. 46 CFR 185.230 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Report of accident to aid to navigation. 185.230 Section 185.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS... aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  18. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Report of accident to aid to navigation. 4.05-20 Section 4.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC... accident to aid to navigation. Whenever a vessel collides with a buoy, or other aid to navigation under...

  19. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Notices to mariners and aids to navigation. 131.910... OPERATIONS Miscellaneous § 131.910 Notices to mariners and aids to navigation. Each master and mate shall... Imagery and Mapping Agency regarding aids to navigation in the area in which the vessel operates....

  20. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Notices to mariners and aids to navigation. 131.910... OPERATIONS Miscellaneous § 131.910 Notices to mariners and aids to navigation. Each master and mate shall... Imagery and Mapping Agency regarding aids to navigation in the area in which the vessel operates....

  1. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Notices to mariners and aids to navigation. 131.910... OPERATIONS Miscellaneous § 131.910 Notices to mariners and aids to navigation. Each master and mate shall... Imagery and Mapping Agency regarding aids to navigation in the area in which the vessel operates....

  2. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Notices to mariners and aids to navigation. 131.910... OPERATIONS Miscellaneous § 131.910 Notices to mariners and aids to navigation. Each master and mate shall... Imagery and Mapping Agency regarding aids to navigation in the area in which the vessel operates....

  3. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Notices to mariners and aids to navigation. 131.910... OPERATIONS Miscellaneous § 131.910 Notices to mariners and aids to navigation. Each master and mate shall... Geospatial-Intelligence Agency regarding aids to navigation in the area in which the vessel operates....

  4. Autonomous navigation system. [gyroscopic pendulum for air navigation

    NASA Technical Reports Server (NTRS)

    Merhav, S. J. (Inventor)

    1981-01-01

    An inertial navigation system utilizing a servo-controlled two degree of freedom pendulum to obtain specific force components in the locally level coordinate system is described. The pendulum includes a leveling gyroscope and an azimuth gyroscope supported on a two gimbal system. The specific force components in the locally level coordinate system are converted to components in the geographical coordinate system by means of a single Euler transformation. The standard navigation equations are solved to determine longitudinal and lateral velocities. Finally, vehicle position is determined by a further integration.

  5. Aided strapdown inertial navigation for autonomous underwater vehicles

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Li, X. Rong

    2010-04-01

    This paper presents a navigation algorithm based on aided strapdown inertial navigation (INS) for an underwater autonomous underwater vehicle (AUV). The AUV is equipped with a long baseline (LBL) acoustic positioning system, acoustic Doppler current profiler (ADCP) and a depth sensor to aid the INS. They have, however, much slower data rates than that of the INS. A linearized, quaternion-based dynamic model and measurement model of the INS output errors are presented. Data from different sensors are fused by applying the extended Kalman filer (EKF) to estimate and correct the errors. Due to the difficulty of generating realistic simulation scenario, real data (raw INS measurement) collected from AUV field experiments are processed to test the algorithm. Without knowing the ground truth, however, performance evaluation becomes much more complicated and needs further research. In this paper, the problem is circumvented by considering the post-processed real data as the "ground truth" and noisy raw measurements are generated from this "ground truth" to feed the algorithm. The simulation results demonstrate the algorithm applicability and show that by incorporating readings from the ADCP and the depth sensor, the (horizontal) position errors still increase but with a significant lower rate than the case of stand-alone operation. If the LBL sensor is further included, the navigation errors can be constrained within a certain bound.

  6. Multifiber optical bend sensor to aid colonoscope navigation

    NASA Astrophysics Data System (ADS)

    Kesner, Jessica E.; Gavalis, Robb M.; Wong, Peter Y.; Cao, Caroline G. L.

    2011-12-01

    A colonoscopy's near-blind navigation process frequently causes disorientation for the scope operator, leading to harm for the patient. Navigation can be improved if real-time colonoscope shape, location, and orientation information is provided by a shape-tracking aid, such as a fiber optic bend sensor. Fiber optic bend sensors provide advantages over conventional electromechanical shape-trackers, including low cost and ease of integration. However, current fiber optic bend sensors lack either the ability to detect both bending direction and curvature, or the ability to detect multiple localized bends. An inexpensive multifiber bend sensor was developed to aid users in navigation during colonoscopy. The bend sensor employs active-cladding optical fibers modified with fluorescent quantum dots, bandpass filters, and a complementary metal-oxide-semiconductor imager as key components. Results from three-fiber sensors demonstrate the bend sensor's ability to measure curvature (error of 0.01 mm), direction (100% accuracy), and location (predetermined distance) of a bend in the fiber bundle. Comparison with spectroscopy data further confirmed the accuracy of the bending direction measurement for a three-fiber sensor. Future work includes improvements in fiber manufacturing to increase sensor sensitivity and consistency. An expanded 31 fiber bundle would be needed to track the full length of a colonoscope.

  7. 47 CFR 24.55 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Antenna structures; air navigation safety. 24... SERVICES PERSONAL COMMUNICATIONS SERVICES Technical Standards § 24.55 Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become...

  8. 47 CFR 24.55 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Antenna structures; air navigation safety. 24... SERVICES PERSONAL COMMUNICATIONS SERVICES Technical Standards § 24.55 Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become...

  9. 47 CFR 24.55 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Antenna structures; air navigation safety. 24... SERVICES PERSONAL COMMUNICATIONS SERVICES Technical Standards § 24.55 Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become...

  10. 47 CFR 24.55 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Antenna structures; air navigation safety. 24... SERVICES PERSONAL COMMUNICATIONS SERVICES Technical Standards § 24.55 Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become...

  11. 47 CFR 24.55 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Antenna structures; air navigation safety. 24... SERVICES PERSONAL COMMUNICATIONS SERVICES Technical Standards § 24.55 Antenna structures; air navigation safety. Licensees that own their antenna structures must not allow these antenna structures to become...

  12. Soft tissue navigation using needle-shaped markers: Evaluation of navigation aid tracking accuracy and CT registration

    NASA Astrophysics Data System (ADS)

    Maier-Hein, L.; Maleike, D.; Neuhaus, J.; Franz, A.; Wolf, I.; Meinzer, H.-P.

    2007-03-01

    We evaluate two core modules of a novel soft tissue navigation system. The system estimates the position of a hidden target (e.g. a tumor) during a minimally invasive intervention from the location of a set of optically tracked needle-shaped navigation aids which are placed in the vicinity of the target. The initial position of the target relative to the navigation aids is obtained from a CT scan. The accuracy of the entire system depends on (a) the accuracy for locating a set of navigation aids in a CT image, (b) the accuracy for determining the positions of the navigation aids during the intervention by means of optical tracking, (c) the accuracy for tracking the applicator (e.g. the biopsy needle), and (d) the accuracy of the real-time deformation model which continuously computes the location of the initially determined target point from the current positions of the navigation aids. In this paper, we focus on the first two aspects. We introduce the navigation aids we constructed for our system and show that the needle tips can be tracked with submillimeter accuracy. Furthermore, we present and evaluate three methods for registering a set of navigation aid models with a given CT image. The fully-automatic algorithm outperforms both the manual method and the semi-automatic algorithm, yielding an average distance of 0.27 +/- 0.08 mm between the estimated needle tip position and the reference position.

  13. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation.

    PubMed

    Nitti, Davide O; Bovenga, Fabio; Chiaradia, Maria T; Greco, Mario; Pinelli, Gianpaolo

    2015-07-28

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system.

  14. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation

    PubMed Central

    Nitti, Davide O.; Bovenga, Fabio; Chiaradia, Maria T.; Greco, Mario; Pinelli, Gianpaolo

    2015-01-01

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimate UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system. PMID:26225977

  15. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation.

    PubMed

    Nitti, Davide O; Bovenga, Fabio; Chiaradia, Maria T; Greco, Mario; Pinelli, Gianpaolo

    2015-01-01

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system. PMID:26225977

  16. Vision-aided inertial navigation system for robotic mobile mapping

    NASA Astrophysics Data System (ADS)

    Bayoud, Fadi; Skaloud, Jan

    2008-04-01

    A mapping system by vision-aided inertial navigation was developed for areas where GNSS signals are unreachable. In this framework, a methodology on the integration of vision and inertial sensors is presented, analysed and tested. The system employs the method of “SLAM: Simultaneous Localisation And Mapping” where the only external input available to the system at the beginning of the mapping mission is a number of features with known coordinates. SLAM is a term used in the robotics community to describe the problem of mapping the environment and at the same time using this map to determine the location of the mapping device. Differing from the robotics approach, the presented development stems from the frameworks of photogrammetry and kinematic geodesy that are merged in two filters that run in parallel: the Least-Squares Adjustment (LSA) for features coordinates determination and the Kalman filter (KF) for navigation correction. To test this approach, a mapping system-prototype comprising two CCD cameras and one Inertial Measurement Unit (IMU) is introduced. Conceptually, the outputs of the LSA photogrammetric resection are used as the external measurements for the KF that corrects the inertial navigation. The filtered position and orientation are subsequently employed in the photogrammetric intersection to map the surrounding features that are used as control points for the resection in the next epoch. We confirm empirically the dependency of navigation performance on the quality of the images and the number of tracked features, as well as on the geometry of the stereo-pair. Due to its autonomous nature, the SLAM's performance is further affected by the quality of IMU initialisation and the a-priory assumptions on error distribution. Using the example of the presented system we show that centimetre accuracy can be achieved in both navigation and mapping when the image geometry is optimal.

  17. 14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION... Standards § 151.95 Fences; distance markers; navigational and landing aids; and offsite work. (a) Boundary... navigational aids is eligible for inclusion in a proj- ect whenever necessitated by development on the...

  18. 14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION... Standards § 151.95 Fences; distance markers; navigational and landing aids; and offsite work. (a) Boundary... navigational aids is eligible for inclusion in a proj- ect whenever necessitated by development on the...

  19. 14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION... Standards § 151.95 Fences; distance markers; navigational and landing aids; and offsite work. (a) Boundary... navigational aids is eligible for inclusion in a proj- ect whenever necessitated by development on the...

  20. 14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION... Standards § 151.95 Fences; distance markers; navigational and landing aids; and offsite work. (a) Boundary... navigational aids is eligible for inclusion in a proj- ect whenever necessitated by development on the...

  1. 14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION... Standards § 151.95 Fences; distance markers; navigational and landing aids; and offsite work. (a) Boundary... navigational aids is eligible for inclusion in a proj- ect whenever necessitated by development on the...

  2. Context-Aided Sensor Fusion for Enhanced Urban Navigation

    PubMed Central

    Martí, Enrique David; Martín, David; García, Jesús; de la Escalera, Arturo; Molina, José Manuel; Armingol, José María

    2012-01-01

    The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments. PMID:23223080

  3. Context-aided sensor fusion for enhanced urban navigation.

    PubMed

    Martí, Enrique David; Martín, David; García, Jesús; de la Escalera, Arturo; Molina, José Manuel; Armingol, José María

    2012-01-01

     The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments.

  4. In-flight angular alignment of inertial navigation systems by means of radio aids

    NASA Technical Reports Server (NTRS)

    Tanner, W.

    1972-01-01

    The principles involved in the angular alignment of the inertial reference by nondirectional data from radio aids are developed and compared with conventional methods of alignment such as gyro-compassing and pendulous vertical determination. The specific problem is considered of the space shuttle reentry and a proposed technique for the alignment of the inertial reference system some time before landing. A description is given of the digital simulation of a transponder interrogation system and of its interaction with the inertial navigation system. Data from reentry simulations are used to demonstrate the effectiveness of in-flight inertial system alignment. Concluding remarks refer to other potential applications such as space shuttle orbit insertion and air navigation of conventional aircraft.

  5. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... United States vessels in one or on the navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 7 2011-10-01 2011-10-01 false Notice to mariners; aids to navigation. 167.65-45... PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-45 Notice to mariners; aids...

  6. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... United States vessels in one or on the navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 7 2010-10-01 2010-10-01 false Notice to mariners; aids to navigation. 167.65-45... PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-45 Notice to mariners; aids...

  7. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... United States vessels in one or on the navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 7 2012-10-01 2012-10-01 false Notice to mariners; aids to navigation. 167.65-45... PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-45 Notice to mariners; aids...

  8. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... United States vessels in one or on the navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 7 2013-10-01 2013-10-01 false Notice to mariners; aids to navigation. 167.65-45... PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-45 Notice to mariners; aids...

  9. 46 CFR 35.20-1 - Notice to mariners; aids to navigation-T/OCLB.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 1 2014-10-01 2014-10-01 false Notice to mariners; aids to navigation-T/OCLB. 35.20-1... § 35.20-1 Notice to mariners; aids to navigation—T/OCLB. (a) Licensed officers are required to...

  10. Determining the Navigational Aids Use on the Internet: The Information Technologies Teacher Candidates' Case

    ERIC Educational Resources Information Center

    Kuzu, Abdullah; Firat, Mehmet

    2010-01-01

    The Internet users who fail to cope with navigation may generally face various problems such as disorientation, distraction, low motivation and abandonment of information retrieval. Therefore, navigational aids are frequently used in today's Web browsers and Web sites to help users navigate on the Internet. However, it is asserted that…

  11. Terrain aided navigation for autonomous underwater vehicles with coarse maps

    NASA Astrophysics Data System (ADS)

    Zhou, Ling; Cheng, Xianghong; Zhu, Yixian

    2016-09-01

    Terrain aided navigation (TAN) is a form of geophysical localization technique for autonomous underwater vehicles (AUVs) operating in GPS-denied environments. TAN performance on sensor-rich AUVs has been evaluated in sea trials. However, many challenges remain before TAN can be successfully implemented on sensor-limited AUVs, especially with coarse maps. To improve TAN performance over coarse maps, a Gaussian process (GP) is proposed for the modeling of bathymetric terrain and integrated into the particle filter (GP-PF). GP is applied to provide not only the bathymetric value prediction through learning a set of bathymetric data from coarse maps but also the variance of the prediction. As a measurement update, calculated on bathymetric deviation is performed through the PF to obtain absolute and bounded positioning accuracy. Through the analysis of TAN performance on experimental data for two different terrains with map resolutions of 10-50 m, both the ability of the proposed model to represent the actual bathymetric terrain with accuracy and the effect of the GP-PF for TAN on sensor-limited systems in suited terrain are demonstrated. The experiment results further verify that there is an inverse relationship between the coarseness of the map and the overall TAN accuracy in rough terrains, but there is hardly any relationship between them in relatively flat terrains.

  12. Terrain aided navigation for autonomous underwater vehicles with coarse maps

    NASA Astrophysics Data System (ADS)

    Zhou, Ling; Cheng, Xianghong; Zhu, Yixian

    2016-09-01

    Terrain aided navigation (TAN) is a form of geophysical localization technique for autonomous underwater vehicles (AUVs) operating in GPS-denied environments. TAN performance on sensor-rich AUVs has been evaluated in sea trials. However, many challenges remain before TAN can be successfully implemented on sensor-limited AUVs, especially with coarse maps. To improve TAN performance over coarse maps, a Gaussian process (GP) is proposed for the modeling of bathymetric terrain and integrated into the particle filter (GP-PF). GP is applied to provide not only the bathymetric value prediction through learning a set of bathymetric data from coarse maps but also the variance of the prediction. As a measurement update, calculated on bathymetric deviation is performed through the PF to obtain absolute and bounded positioning accuracy. Through the analysis of TAN performance on experimental data for two different terrains with map resolutions of 10–50 m, both the ability of the proposed model to represent the actual bathymetric terrain with accuracy and the effect of the GP-PF for TAN on sensor-limited systems in suited terrain are demonstrated. The experiment results further verify that there is an inverse relationship between the coarseness of the map and the overall TAN accuracy in rough terrains, but there is hardly any relationship between them in relatively flat terrains.

  13. 47 CFR 27.56 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Antenna structures; air navigation safety. 27.56 Section 27.56 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.56 Antenna structures;...

  14. 47 CFR 27.56 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Antenna structures; air navigation safety. 27.56 Section 27.56 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.56 Antenna structures;...

  15. 47 CFR 27.56 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Antenna structures; air navigation safety. 27.56 Section 27.56 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.56 Antenna structures;...

  16. 47 CFR 27.56 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Antenna structures; air navigation safety. 27.56 Section 27.56 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.56 Antenna structures;...

  17. 47 CFR 27.56 - Antenna structures; air navigation safety.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Antenna structures; air navigation safety. 27.56 Section 27.56 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.56 Antenna structures;...

  18. Learning at Air Navigation Services after Initial Training

    ERIC Educational Resources Information Center

    Teperi, Anna-Maria; Leppanen, Anneli

    2010-01-01

    Purpose: This study aims to find out the means used for individual, group and organizational learning at work at one air navigation service provider after the initial training period. The study also aims to find out what practices need to be improved to enhance learning at work. Design/methodology/approach: The data for the study were collected…

  19. Study Navigator: An Algorithmically Generated Aid for Learning from Electronic Textbooks

    ERIC Educational Resources Information Center

    Agrawal, Rakesh; Gollapudi, Sreenivas; Kannan, Anitha; Kenthapadi, Krishnaram

    2014-01-01

    We present "study navigator," an algorithmically-generated aid for enhancing the experience of studying from electronic textbooks. The study navigator for a section of the book consists of helpful "concept references" for understanding this section. Each concept reference is a pair consisting of a concept phrase explained…

  20. 14 CFR 171.61 - Air navigation certificate: Revocation and termination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Air navigation certificate: Revocation and... TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES True Lights § 171.61 Air navigation certificate: Revocation and termination. (a) Except as provided in paragraph (b) of this...

  1. 14 CFR 171.61 - Air navigation certificate: Revocation and termination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Air navigation certificate: Revocation and... TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES True Lights § 171.61 Air navigation certificate: Revocation and termination. (a) Except as provided in paragraph (b) of this...

  2. 14 CFR 171.61 - Air navigation certificate: Revocation and termination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Air navigation certificate: Revocation and... TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES True Lights § 171.61 Air navigation certificate: Revocation and termination. (a) Except as provided in paragraph (b) of this...

  3. 14 CFR 171.61 - Air navigation certificate: Revocation and termination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Air navigation certificate: Revocation and... TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES True Lights § 171.61 Air navigation certificate: Revocation and termination. (a) Except as provided in paragraph (b) of this...

  4. 14 CFR 171.61 - Air navigation certificate: Revocation and termination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Air navigation certificate: Revocation and... TRANSPORTATION (CONTINUED) NAVIGATIONAL FACILITIES NON-FEDERAL NAVIGATION FACILITIES True Lights § 171.61 Air navigation certificate: Revocation and termination. (a) Except as provided in paragraph (b) of this...

  5. 46 CFR 35.20-1 - Notice to mariners; aids to navigation-T/OCLB.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 33 CFR 164.33. ... 46 Shipping 1 2011-10-01 2011-10-01 false Notice to mariners; aids to navigation-T/OCLB. 35.20-1... § 35.20-1 Notice to mariners; aids to navigation—T/OCLB. (a) Licensed officers are required to...

  6. 46 CFR 35.20-1 - Notice to mariners; aids to navigation-T/OCLB.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 33 CFR 164.33. ... 46 Shipping 1 2013-10-01 2013-10-01 false Notice to mariners; aids to navigation-T/OCLB. 35.20-1... § 35.20-1 Notice to mariners; aids to navigation—T/OCLB. (a) Licensed officers are required to...

  7. 46 CFR 35.20-1 - Notice to mariners; aids to navigation-T/OCLB.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 33 CFR 164.33. ... 46 Shipping 1 2010-10-01 2010-10-01 false Notice to mariners; aids to navigation-T/OCLB. 35.20-1... § 35.20-1 Notice to mariners; aids to navigation—T/OCLB. (a) Licensed officers are required to...

  8. 46 CFR 35.20-1 - Notice to mariners; aids to navigation-T/OCLB.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 33 CFR 164.33. ... 46 Shipping 1 2012-10-01 2012-10-01 false Notice to mariners; aids to navigation-T/OCLB. 35.20-1... § 35.20-1 Notice to mariners; aids to navigation—T/OCLB. (a) Licensed officers are required to...

  9. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... United States, see 33 CFR 164.33. ... 46 Shipping 7 2014-10-01 2014-10-01 false Notice to mariners; aids to navigation. 167.65-45... PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-45 Notice to mariners; aids...

  10. 75 FR 1799 - Terminate Long Range Aids to Navigation (Loran-C) Signal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... Register of January 7, 2010 (75 FR 998). The document announced termination of the Long Range Aids to... January 7, 2010, in ] FR Doc. 2010-83, on page 998 in the second column under DATES, correct... SECURITY Coast Guard Terminate Long Range Aids to Navigation (Loran-C) Signal AGENCY: U.S. Coast Guard,...

  11. NAVSIM 2: A computer program for simulating aided-inertial navigation for aircraft

    NASA Technical Reports Server (NTRS)

    Bjorkman, William S.

    1987-01-01

    NAVSIM II, a computer program for analytical simulation of aided-inertial navigation for aircraft, is described. The description is supported by a discussion of the program's application to the design and analysis of aided-inertial navigation systems as well as instructions for utilizing the program and for modifying it to accommodate new models, constraints, algorithms and scenarios. NAVSIM II simulates an airborne inertial navigation system built around a strapped-down inertial measurement unit and aided in its function by GPS, Doppler radar, altimeter, airspeed, and position-fix measurements. The measurements are incorporated into the navigation estimate via a UD-form Kalman filter. The simulation was designed and implemented using structured programming techniques and with particular attention to user-friendly operation.

  12. An Imaging Sensor-Aided Vision Navigation Approach that Uses a Geo-Referenced Image Database.

    PubMed

    Li, Yan; Hu, Qingwu; Wu, Meng; Gao, Yang

    2016-01-28

    In determining position and attitude, vision navigation via real-time image processing of data collected from imaging sensors is advanced without a high-performance global positioning system (GPS) and an inertial measurement unit (IMU). Vision navigation is widely used in indoor navigation, far space navigation, and multiple sensor-integrated mobile mapping. This paper proposes a novel vision navigation approach aided by imaging sensors and that uses a high-accuracy geo-referenced image database (GRID) for high-precision navigation of multiple sensor platforms in environments with poor GPS. First, the framework of GRID-aided vision navigation is developed with sequence images from land-based mobile mapping systems that integrate multiple sensors. Second, a highly efficient GRID storage management model is established based on the linear index of a road segment for fast image searches and retrieval. Third, a robust image matching algorithm is presented to search and match a real-time image with the GRID. Subsequently, the image matched with the real-time scene is considered to calculate the 3D navigation parameter of multiple sensor platforms. Experimental results show that the proposed approach retrieves images efficiently and has navigation accuracies of 1.2 m in a plane and 1.8 m in height under GPS loss in 5 min and within 1500 m.

  13. An Imaging Sensor-Aided Vision Navigation Approach that Uses a Geo-Referenced Image Database

    PubMed Central

    Li, Yan; Hu, Qingwu; Wu, Meng; Gao, Yang

    2016-01-01

    In determining position and attitude, vision navigation via real-time image processing of data collected from imaging sensors is advanced without a high-performance global positioning system (GPS) and an inertial measurement unit (IMU). Vision navigation is widely used in indoor navigation, far space navigation, and multiple sensor-integrated mobile mapping. This paper proposes a novel vision navigation approach aided by imaging sensors and that uses a high-accuracy geo-referenced image database (GRID) for high-precision navigation of multiple sensor platforms in environments with poor GPS. First, the framework of GRID-aided vision navigation is developed with sequence images from land-based mobile mapping systems that integrate multiple sensors. Second, a highly efficient GRID storage management model is established based on the linear index of a road segment for fast image searches and retrieval. Third, a robust image matching algorithm is presented to search and match a real-time image with the GRID. Subsequently, the image matched with the real-time scene is considered to calculate the 3D navigation parameter of multiple sensor platforms. Experimental results show that the proposed approach retrieves images efficiently and has navigation accuracies of 1.2 m in a plane and 1.8 m in height under GPS loss in 5 min and within 1500 m. PMID:26828496

  14. An Imaging Sensor-Aided Vision Navigation Approach that Uses a Geo-Referenced Image Database.

    PubMed

    Li, Yan; Hu, Qingwu; Wu, Meng; Gao, Yang

    2016-01-01

    In determining position and attitude, vision navigation via real-time image processing of data collected from imaging sensors is advanced without a high-performance global positioning system (GPS) and an inertial measurement unit (IMU). Vision navigation is widely used in indoor navigation, far space navigation, and multiple sensor-integrated mobile mapping. This paper proposes a novel vision navigation approach aided by imaging sensors and that uses a high-accuracy geo-referenced image database (GRID) for high-precision navigation of multiple sensor platforms in environments with poor GPS. First, the framework of GRID-aided vision navigation is developed with sequence images from land-based mobile mapping systems that integrate multiple sensors. Second, a highly efficient GRID storage management model is established based on the linear index of a road segment for fast image searches and retrieval. Third, a robust image matching algorithm is presented to search and match a real-time image with the GRID. Subsequently, the image matched with the real-time scene is considered to calculate the 3D navigation parameter of multiple sensor platforms. Experimental results show that the proposed approach retrieves images efficiently and has navigation accuracies of 1.2 m in a plane and 1.8 m in height under GPS loss in 5 min and within 1500 m. PMID:26828496

  15. Real Time Mars Approach Navigation Aided by the Mars Network

    NASA Technical Reports Server (NTRS)

    Ely, Todd A.; Duncan, Courtney; Lightsey, E. Glenn; Mogensen, Andreas

    2006-01-01

    A NASA Mars technology project is described that is building a prototype embedded real time Mars approach navigation capability which can be hosted on the Mars Network's Electra transceiver. The paper motivates the reason for doing real time Mars approach navigation via a set of analyses demonstrating its utility for enabling Mars pin-point landing (< 1-km landing error). The development approach, software design, and test results are discussed. Finally, the way forward towards a flight demonstration on the Mars Science Laboratory is presented.

  16. Real Time Mars Approach Navigation Aided by the Mars Network

    NASA Technical Reports Server (NTRS)

    Ely, Todd A.; Duncan, Courtney; Lightsey, E. Glenn; Mogensen, Andreas

    2006-01-01

    A NASA Mars technology project is described that is building a prototype embedded real time Mars approach navigation capability which can be hosted on the Mars Network's Electra transceiver. The paper motivates the reason for doing real time Mars approach navigation via a set of analyses demonstrating its utility for enabling Mars pin-point landing (less than 1-km landing error). The development approach, software design, and test results are discussed. Finally, the way forward towards a flight demonstration on the Mars Science Laboratory (MSL) is presented.

  17. Integration of Visibility Sensors in NOAA PORTS® to aid in Decision Making for Safe Navigation

    NASA Astrophysics Data System (ADS)

    Roggenstein, E. B.

    2012-12-01

    The National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) Physical Oceanographic Real-Time System (PORTS®) provides real-time water level, currents and meteorological data for aid to navigation in twenty-three major ports and harbors. In response to PORTS® users' requests for visibility data, NOS began testing several varieties of visibility sensors for operations in a marine environment. Extensive testing resulted in the selection of the Vaisala FS11 visibility sensor. The FS11 sensor uses forward scattering technology to measure the amount of scattering in a small volume of air between the transmitter and receiver, resulting in an extrapolated visibility at a set height out to 75 km. Two sensors have been successfully operating in the Mobile Bay PORTS® at Middle Bay Port and Pinto Island since installation in 2010. The sensors are positioned at a height of 3 m above the ground, 24 km apart along the western shore of the bay in areas susceptible to fog formation. Real-time data from these sensors are disseminated on NOAA's Center for Operational Oceanographic Products and Services (COOPS) PORTS® website every 6 minutes (min) and for distances up to 10 km (5.4 nm) from the instrument. This has proven to aid port pilots' decision making for safe movement of vessels in the harbor. Additionally, the Pinto Island sensor is located directly adjacent to the shipping channel - an area with high levels of atmospheric particulates of high carbon content. These particulates do not appear to have negatively affected sensor performance. This success has prompted interest in visibility sensors from other harbors with PORTS®. The ports of San Francisco, Narragansett Bay, Chesapeake Bay, Jacksonville FL, and Gulfport MS are planning or exploring the addition of visibility sensors to their PORTS® to aid in navigation. Additionally, the NOAA/COOPS Ocean System Test Evaluation Program (OSTEP) has continued with additional field testing of the FS11

  18. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or interest to general navigation. Notice need not be given as to such buoys, lights, or fog signals... also lights or fog signals on ferry slips and on piers used only by certain vessels, and stakes,...

  19. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or interest to general navigation. Notice need not be given as to such buoys, lights, or fog signals... also lights or fog signals on ferry slips and on piers used only by certain vessels, and stakes,...

  20. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or interest to general navigation. Notice need not be given as to such buoys, lights, or fog signals... also lights or fog signals on ferry slips and on piers used only by certain vessels, and stakes,...

  1. Sensor-based navigation of air duct inspection mobile robots

    NASA Astrophysics Data System (ADS)

    Koh, Kyoungchul; Choi, H. J.; Kim, Jae-Seon; Ko, Kuk Won; Cho, Hyungsuck

    2001-02-01

    12 This paper deals with an image sensor system and its position estimation algorithm for autonomous duct cleaning and inspection mobile robots. For the real application, a hierarchical control structure that consists of robot motion controller and image sensor system is designed considering the efficient and autonomous motion behaviors in narrow space such as air ducts. The sensor's system consists of a CCD camera and two laser sources to generate slit beams. The image of the structured lights is used for calculating the geometric parameters of the air ducts which are usually designed with a rectangular section. With the acquired 3D information about the environment, the mobile robot with two differential driving wheels is able to autonomously navigates along the duct path without any human intervention. For real time navigation, the relative position estimation of the robot are performed from 3D image reconstructed by the sensor system. The calibration and image processing methods used for the sensor system are presented with the experimental data. The experimental results show the possibility of the sensor based navigation which is important for effective duct cleaning by small mobile robots.

  2. GPS Auto-Navigation Design for Unmanned Air Vehicles

    NASA Technical Reports Server (NTRS)

    Nilsson, Caroline C. A.; Heinzen, Stearns N.; Hall, Charles E., Jr.; Chokani, Ndaona

    2003-01-01

    A GPS auto-navigation system is designed for Unmanned Air Vehicles. The objective is to enable the air vehicle to be used as a test-bed for novel flow control concepts. The navigation system uses pre-programmed GPS waypoints. The actual GPS position, heading, and velocity are collected by the flight computer, a PC104 system running in Real-Time Linux, and compared with the desired waypoint. The navigator then determines the necessity of a heading correction and outputs the correction in the form of a commanded bank angle, for a level coordinated turn, to the controller system. This controller system consists of 5 controller! (pitch rate PID, yaw damper, bank angle PID, velocity hold, and altitude hold) designed for a closed loop non-linear aircraft model with linear aerodynamic coefficients. The ability and accuracy of using GPS data, is validated by a GPS flight. The autopilots are also validated in flight. The autopilot unit flight validations show that the designed autopilots function as designed. The aircraft model, generated on Matlab SIMULINK is also enhanced by the flight data to accurately represent the actual aircraft.

  3. The Vector Matching Method in Geomagnetic Aiding Navigation

    PubMed Central

    Song, Zhongguo; Zhang, Jinsheng; Zhu, Wenqi; Xi, Xiaoli

    2016-01-01

    In this paper, a geomagnetic matching navigation method that utilizes the geomagnetic vector is developed, which can greatly improve the matching probability and positioning precision, even when the geomagnetic entropy information in the matching region is small or the geomagnetic contour line’s variety is obscure. The vector iterative closest contour point (VICCP) algorithm that is proposed here has better adaptability with the positioning error characteristics of the inertial navigation system (INS), where the rigid transformation in ordinary ICCP is replaced with affine transformation. In a subsequent step, a geomagnetic vector information fusion algorithm based on Bayesian statistical analysis is introduced into VICCP to improve matching performance further. Simulations based on the actual geomagnetic reference map have been performed for the validation of the proposed algorithm. PMID:27447645

  4. The Vector Matching Method in Geomagnetic Aiding Navigation.

    PubMed

    Song, Zhongguo; Zhang, Jinsheng; Zhu, Wenqi; Xi, Xiaoli

    2016-01-01

    In this paper, a geomagnetic matching navigation method that utilizes the geomagnetic vector is developed, which can greatly improve the matching probability and positioning precision, even when the geomagnetic entropy information in the matching region is small or the geomagnetic contour line's variety is obscure. The vector iterative closest contour point (VICCP) algorithm that is proposed here has better adaptability with the positioning error characteristics of the inertial navigation system (INS), where the rigid transformation in ordinary ICCP is replaced with affine transformation. In a subsequent step, a geomagnetic vector information fusion algorithm based on Bayesian statistical analysis is introduced into VICCP to improve matching performance further. Simulations based on the actual geomagnetic reference map have been performed for the validation of the proposed algorithm. PMID:27447645

  5. Air Navigation. Flying Training. AFM 51-40. NAVAIR 00-80V-49.

    ERIC Educational Resources Information Center

    Air Training Command, Randolph AFB, TX.

    This manual provides information on all phases of air navigation for navigators and student navigators in training. It develops the art of navigation from the simplest concepts to the most advanced procedures and techniques. The text contains explanations on how to measure, map, and chart the earth; how to use basic instruments to obtain…

  6. Semiotic evaluation of Lithuania military air navigation charts

    NASA Astrophysics Data System (ADS)

    Ovodas, Donatas; Česnulevičius, Algimantas

    2014-06-01

    Research of semiotic aspects Lithuanian military air navigation charts was based on the semantic, graphic and information load analysis. The aim of semantic analysis was to determine how the conventional cartographical symbols, used in air navigation charts, correspond with carto-linguistic and carto-semiotic requirements. The analysis of all the markings was performed complex and collected by questionnaire were interviewed various respondents: pilots, cartographers and other chart users. The researches seek two aims: evaluate information and graphical load of military air navigation charts. Information load evaluated to calculate all objects and phenomenon, which was in 25 cm² of map. Charts analysis showed that in low flight charts (LFC) average information load are 4 - 5 times richer than in the operational maps. Map signs optimization on LFC has to be managed very carefully, choosing signs that can reduce the load of information and helps for the information transfer process. Graphical load of maps evaluated of aeronautical maps is not great (5 - 12%) and does not require reduction the information load and generalization of charts. Air navigation charts analysis pointed that not all air navigation sings correspond carto-semiotic requirements and must be improved. The authors suggested some new sings for military air navigation chart, which are simpler, equivalent to human psychophysical perception criteria, creates faster communication and less load on the chart. Badania semiotycznych aspektów litewskich wojskowych map żeglugi powietrznej bazowały na semantycznej, graficznej i informacyjnej analizie treści tych map. Celem analizy semantycznej było określenie na ile tradycyjne symbole kartograficzne stosowane na mapach nawigacji lotniczej są zgodne z wymogami języka kartograficznego oraz zasadami stosowania znaków kartograficznych. Powyższe analizy przeprowadzono w sposób kompleksowy, informacje zebrano za pomocą ankiet, przeprowadzając wywiady w r

  7. RFID based indoor navigational aid for persons with severe visual impairments.

    PubMed

    Szeto, Andrew Y J; Sharma, Satish K

    2007-01-01

    A flexible, low cost, and portable indoor navigational aid for persons who are blind or have severe visual impairments remains an unmet need and a technical challenge. Whereas devices using global positioning system (GPS) signals hold promise for navigational assistance in the outdoor environment, they do not work where GPS signals are absent or greatly attenuated. Thus a network of navigational beacons is needed for the indoor environment. This paper describes the promise of an indoor navigational aid that relies on a network of custom extended-range RFID tags. RFID (radio-frequency identification) technology has the advantages of being low cost, unobtrusive, and highly flexible in the sense that sight impaired travelers can use personalized RFID tags to mark indoor locations of their particular interest. However, commercially available RFID tags have very short detection ranges. To make them suitable as indoor electronic beacons, their range of detection must be greatly extended. Some of the technical challenges and proposed solutions that can extend the detection range are discussed in this paper following an overview of the proposed RFID based indoor navigational aid.

  8. 76 FR 77585 - Notice to Manufacturers of Airport Lighting and Navigation Aid Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-13

    ...Projects funded under the Airport Improvement Program (AIP) must meet the requirements of 49 U.S.C. 50101, Buy American Preferences. The Federal Aviation Administration (FAA) is considering issuing waivers to foreign manufacturers of certain airport lighting and navigation aid equipment that is lit with Light Emitting Diode (LED) lighting. This notice requests information from manufacturers of......

  9. 75 FR 998 - Terminate Long Range Aids to Navigation (Loran-C) Signal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-07

    ... FR 4047), the U.S. Coast Guard began a public review process for its Draft Programmatic Environmental... SECURITY Coast Guard Terminate Long Range Aids to Navigation (Loran-C) Signal AGENCY: U.S. Coast Guard, DHS... Homeland Security Appropriations Act. The Act allows for the termination of the Loran-C system subject...

  10. Ames-aided inertial navigation work - The first two years of progress

    NASA Technical Reports Server (NTRS)

    Smith, G. L.

    1973-01-01

    A description of work whose broad objective is to attain improved aircraft navigation performance through exploitation of the concept of combining navigation data from several sources in an optimum manner is presented. The system developed as a result of the work, called RAINPAL (Recursive Aided Inertial Navigation for Precision Approach and Landing) is designed to combine precision radio range measurements with data from on-board inertial sensors to achieve precision navigation for approach and landing. The paper describes RAINPAL and the rationale of its design, and also serves as a sort of planning document, including a progress report, a summary of objectives past and present, and an exposition of reasons for doing the work.

  11. Computer program for design and performance analysis of navigation-aid power systems

    NASA Technical Reports Server (NTRS)

    Weiner, H.; Wiener, P.; Williams, K.

    1976-01-01

    The paper examines the requirements, design rationale, operation, and verification of a computer program designated as design synthesis/performance analysis (DSPA) computer program, which is capable of performing all the calculations necessary to understand the overall characteristics of solar array/battery power systems for navigation-aid applications. Despite the uncertainties in the erratic solar array degradation data and the potential impact on actual battery behavior, verification of the DSPA is considered successful. The program is shown to have the capability of simulating the performance of solar array/battery navigation-aid power systems. It can also be used to synthesize power system designs and provide essential design and cost data.

  12. Research on aided navigation based on terrain elevation matching and simulation

    NASA Astrophysics Data System (ADS)

    He, Yanping; Liu, Xinxue; Cai, Yanping; Zhu, Yu

    2016-01-01

    The matching function of terrain-aided navigation is not only related to the algorithm, also associated with the terrain characteristics of matching area. Aiming at terrain matching area selection and matching algorithm of the terrain height matching system, the method of terrain information entropy is put forward on the basis of statistical characteristics of the terrain roughness, signal-to-noise ratio, and then COR algorithm, MAD algorithm, MSD algorithm is adopted for real-time map and reference map matching, finally shows the simulation comparison of three kinds of matching algorithm. Result of simulation shows that among the index of matching accuracy and speed of three kinds of algorithm, COR algorithm possess fastest calculation speed and lowest precision, matching accuracy of MSD is slightly higher than MAD algorithm and calculation speed of MSD is placed in the middle, and the simulation results provide selection basis for terrain-aided inertial navigation.

  13. Development of performance measures based on visibility for effective placement of aids to navigation

    NASA Astrophysics Data System (ADS)

    Fang, Tae Hyun; Kim, Yeon-Gyu; Gong, In-Young; Park, Sekil; Kim, Ah-Young

    2015-09-01

    In order to develop the challenging process of placing Aids to Navigation (AtoN), we propose performance measures which quantifies the effect of such placement. The best placement of AtoNs is that from which the navigator can best recognize the information provided by an AtoN. The visibility of AtoNs depends mostly on light sources, the weather condition and the position of the navigator. Visual recognition is enabled by achieving adequate contrast between the AtoN light source and background light. Therefore, the performance measures can be formulated through the amount of differences between these two lights. For simplification, this approach is based on the values of the human factor suggested by International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). Performance measures for AtoN placement can be evaluated through AtoN Simulator, which has been being developed by KIOST/KRISO in Korea and has been launched by Korea National Research Program. Simulations for evaluation are carried out at waterway in Busan port in Korea.

  14. Development of performance measures based on visibility for effective placement of aids to navigation

    NASA Astrophysics Data System (ADS)

    Fang, Tae Hyun; Kim, Yeon-Gyu; Gong, In-Young; Park, Sekil; Kim, Ah-Young

    2015-05-01

    In order to develop the challenging process of placing Aids to Navigation (AtoN), we propose performance measures which quantifies the effect of such placement. The best placement of AtoNs is that from which the navigator can best recognize the information provided by an AtoN. The visibility of AtoNs depends mostly on light sources, the weather condition and the position of the navigator. Visual recognition is enabled by achieving adequate contrast between the AtoN light source and background light. Therefore, the performance measures can be formulated through the amount of differences between these two lights. For simplification, this approach is based on the values of the human factor suggested by International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). Performance measures for AtoN placement can be evaluated through AtoN Simulator, which has been being developed by KIOST/KRISO in Korea and has been launched by Korea National Research Program. Simulations for evaluation are carried out at waterway in Busan port in Korea.

  15. Coupled Inertial Navigation and Flush Air Data Sensing Algorithm for Atmosphere Estimation

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberger, Mark

    2015-01-01

    This paper describes an algorithm for atmospheric state estimation that is based on a coupling between inertial navigation and flush air data sensing pressure measurements. In this approach, the full navigation state is used in the atmospheric estimation algorithm along with the pressure measurements and a model of the surface pressure distribution to directly estimate atmospheric winds and density using a nonlinear weighted least-squares algorithm. The approach uses a high fidelity model of atmosphere stored in table-look-up form, along with simplified models of that are propagated along the trajectory within the algorithm to provide prior estimates and covariances to aid the air data state solution. Thus, the method is essentially a reduced-order Kalman filter in which the inertial states are taken from the navigation solution and atmospheric states are estimated in the filter. The algorithm is applied to data from the Mars Science Laboratory entry, descent, and landing from August 2012. Reasonable estimates of the atmosphere and winds are produced by the algorithm. The observability of winds along the trajectory are examined using an index based on the discrete-time observability Gramian and the pressure measurement sensitivity matrix. The results indicate that bank reversals are responsible for adding information content to the system. The algorithm is then applied to the design of the pressure measurement system for the Mars 2020 mission. The pressure port layout is optimized to maximize the observability of atmospheric states along the trajectory. Linear covariance analysis is performed to assess estimator performance for a given pressure measurement uncertainty. The results indicate that the new tightly-coupled estimator can produce enhanced estimates of atmospheric states when compared with existing algorithms.

  16. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments.

    PubMed

    Tang, Jian; Chen, Yuwei; Niu, Xiaoji; Wang, Li; Chen, Liang; Liu, Jingbin; Shi, Chuang; Hyyppä, Juha

    2015-07-10

    A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies-INS and LiDAR SLAM-into one navigation frame with a loosely coupled Extended Kalman Filter (EKF) to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV) platform-NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment.

  17. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments

    PubMed Central

    Tang, Jian; Chen, Yuwei; Niu, Xiaoji; Wang, Li; Chen, Liang; Liu, Jingbin; Shi, Chuang; Hyyppä, Juha

    2015-01-01

    A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies—INS and LiDAR SLAM—into one navigation frame with a loosely coupled Extended Kalman Filter (EKF) to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV) platform—NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment. PMID:26184206

  18. LiDAR Scan Matching Aided Inertial Navigation System in GNSS-Denied Environments.

    PubMed

    Tang, Jian; Chen, Yuwei; Niu, Xiaoji; Wang, Li; Chen, Liang; Liu, Jingbin; Shi, Chuang; Hyyppä, Juha

    2015-01-01

    A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies-INS and LiDAR SLAM-into one navigation frame with a loosely coupled Extended Kalman Filter (EKF) to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV) platform-NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment. PMID:26184206

  19. Underwater terrain-aided navigation based on multibeam bathymetric sonar images

    NASA Astrophysics Data System (ADS)

    Song, Ziqi; Bian, Hongyu; Zielinski, Adam

    2015-12-01

    Underwater terrain-aided navigation is used to complement traditional inertial navigation employed by autonomous underwater vehicles during lengthy missions. It can provide fixed estimations by matching real-time depth data with a digital terrain map. This study presents the concept of using image processing techniques in the underwater terrain matching process. A traditional gray-scale histogram of an image is enriched by incorporation with spatial information in pixels. Edge corner pixels are then defined and used to construct an edge corner histogram, which it employs as a template to scan the digital terrain map and estimate the fixes of the vehicle by searching the correlation peak. Simulations are performed to investigate the robustness of the proposed method, particularly in relation to its sensitivity to background noise, the scale of real-time images, and the travel direction of the vehicle. At an image resolution of 1 m2/pixel, the accuracy of localization is more than 10 meters.

  20. Triangulating laser profilometer as a navigational aid for the blind: optical aspects

    NASA Astrophysics Data System (ADS)

    Farcy, R.; Denise, B.; Damaschini, R.

    1996-03-01

    We propose a navigational aid approach for the blind that relies on active optical profilometry with real-time electrotactile interfacing on the skin. Here we are concerned with the optical parts of this system. We point out the particular requirements the profilometer must meet to meet the needs of blind people. We show experimentally that an adequate compromise is possible that consists of a compact class I IR laser-diode triangulation profilometer with the following angular resolution, 20-ms acquisition time per measure of distance, 60 degrees angular scanning field.

  1. Flight results from a study of aided inertial navigation applied to landing operations

    NASA Technical Reports Server (NTRS)

    Mcgee, L. A.; Smith, G. L.; Hegarty, D. M.; Carson, T. M.; Merrick, R. B.; Schmidt, S. F.; Conrad, B.

    1973-01-01

    An evaluation is presented of the approach and landing performance of a Kalman filter aided inertial navigation system using flight data obtained from a series of approaches and landings of the CV-340 aircraft at an instrumented test area. A description of the flight test is given, in which data recorded included: (1) accelerometer signals from the platform of an INS; (2) three ranges from the Ames-Cubic Precision Ranging System; and (3) radar and barometric altimeter signals. The method of system evaluation employed was postflight processing of the recorded data using a Kalman filter which was designed for use on the XDS920 computer onboard the CV-340 aircraft. Results shown include comparisons between the trajectories as estimated by the Kalman filter aided system and as determined from cinetheodolite data. Data start initialization of the Kalman filter, operation at a practical data rate, postflight modeling of sensor errors and operation under the adverse condition of bad data are illustrated.

  2. Navigation Aiding by a Hybrid Laser-Camera Motion Estimator for Micro Aerial Vehicles.

    PubMed

    Atman, Jamal; Popp, Manuel; Ruppelt, Jan; Trommer, Gert F

    2016-09-16

    Micro Air Vehicles (MAVs) equipped with various sensors are able to carry out autonomous flights. However, the self-localization of autonomous agents is mostly dependent on Global Navigation Satellite Systems (GNSS). In order to provide an accurate navigation solution in absence of GNSS signals, this article presents a hybrid sensor. The hybrid sensor is a deep integration of a monocular camera and a 2D laser rangefinder so that the motion of the MAV is estimated. This realization is expected to be more flexible in terms of environments compared to laser-scan-matching approaches. The estimated ego-motion is then integrated in the MAV's navigation system. However, first, the knowledge about the pose between both sensors is obtained by proposing an improved calibration method. For both calibration and ego-motion estimation, 3D-to-2D correspondences are used and the Perspective-3-Point (P3P) problem is solved. Moreover, the covariance estimation of the relative motion is presented. The experiments show very accurate calibration and navigation results.

  3. Navigation Aiding by a Hybrid Laser-Camera Motion Estimator for Micro Aerial Vehicles.

    PubMed

    Atman, Jamal; Popp, Manuel; Ruppelt, Jan; Trommer, Gert F

    2016-01-01

    Micro Air Vehicles (MAVs) equipped with various sensors are able to carry out autonomous flights. However, the self-localization of autonomous agents is mostly dependent on Global Navigation Satellite Systems (GNSS). In order to provide an accurate navigation solution in absence of GNSS signals, this article presents a hybrid sensor. The hybrid sensor is a deep integration of a monocular camera and a 2D laser rangefinder so that the motion of the MAV is estimated. This realization is expected to be more flexible in terms of environments compared to laser-scan-matching approaches. The estimated ego-motion is then integrated in the MAV's navigation system. However, first, the knowledge about the pose between both sensors is obtained by proposing an improved calibration method. For both calibration and ego-motion estimation, 3D-to-2D correspondences are used and the Perspective-3-Point (P3P) problem is solved. Moreover, the covariance estimation of the relative motion is presented. The experiments show very accurate calibration and navigation results. PMID:27649203

  4. Navigation Aiding by a Hybrid Laser-Camera Motion Estimator for Micro Aerial Vehicles

    PubMed Central

    Atman, Jamal; Popp, Manuel; Ruppelt, Jan; Trommer, Gert F.

    2016-01-01

    Micro Air Vehicles (MAVs) equipped with various sensors are able to carry out autonomous flights. However, the self-localization of autonomous agents is mostly dependent on Global Navigation Satellite Systems (GNSS). In order to provide an accurate navigation solution in absence of GNSS signals, this article presents a hybrid sensor. The hybrid sensor is a deep integration of a monocular camera and a 2D laser rangefinder so that the motion of the MAV is estimated. This realization is expected to be more flexible in terms of environments compared to laser-scan-matching approaches. The estimated ego-motion is then integrated in the MAV’s navigation system. However, first, the knowledge about the pose between both sensors is obtained by proposing an improved calibration method. For both calibration and ego-motion estimation, 3D-to-2D correspondences are used and the Perspective-3-Point (P3P) problem is solved. Moreover, the covariance estimation of the relative motion is presented. The experiments show very accurate calibration and navigation results. PMID:27649203

  5. Surgical treatment of distal anterior cerebral artery aneurysms aided by electromagnetic navigation CT angiography.

    PubMed

    Hermann, Elvis J; Petrakakis, Ioannis; Götz, Friedrich; Lütjens, Götz; Lang, Josef; Nakamura, Makoto; Krauss, Joachim K

    2015-07-01

    The surgical treatment of distal anterior cerebral artery (DACA) aneurysms still presents a challenge for neurosurgeons because of their small size and their location in the depth of the narrow frontal interhemispheric fissure. This study aimed to investigate feasibility, safety, accuracy, and usefulness of electromagnetic (EM) navigation to aid clipping of DACA aneurysms. Eight patients (age between 2 and 68 years, mean age 49.8 years) with a DACA aneurysm underwent EM-guided neuronavigated microsurgery for clipping of the aneurysm. All patients underwent craniocervical 3D-CT angiography preoperatively. After planning the optimal approach and surgical trajectory avoiding opening of the frontal sinus, the head was fixed. Intraoperative screenshots were correlated with the microscopical view of the DACA aneurysms before clipping. EM-guided neuronavigation using CT angiography for DACA aneurysms enabled fast and accurate referencing of the patient and planning of a tailored craniotomy without opening of the frontal sinus. Intraoperative accuracy was highly reliable except in one instance due to dislocation of the dynamic reference frame (DRF). There was a good correlation between the 3D-CT angiography-based navigation data sets and the intraoperative vascular anatomy. In all patients, bridging veins were spared. The aid of EM neuronavigation was considered useful in all instances. EM-guided neuronavigation using CT angiography for surgery of DACA aneurysms is a useful tool optimizing the surgical approach directly to the aneurysm minimizing additional damage to the surrounding tissue during preparation of the aneurysm and the parent vessel. PMID:25666391

  6. A Depth-Based Head-Mounted Visual Display to Aid Navigation in Partially Sighted Individuals

    PubMed Central

    Hicks, Stephen L.; Wilson, Iain; Muhammed, Louwai; Worsfold, John; Downes, Susan M.; Kennard, Christopher

    2013-01-01

    Independent navigation for blind individuals can be extremely difficult due to the inability to recognise and avoid obstacles. Assistive techniques such as white canes, guide dogs, and sensory substitution provide a degree of situational awareness by relying on touch or hearing but as yet there are no techniques that attempt to make use of any residual vision that the individual is likely to retain. Residual vision can restricted to the awareness of the orientation of a light source, and hence any information presented on a wearable display would have to limited and unambiguous. For improved situational awareness, i.e. for the detection of obstacles, displaying the size and position of nearby objects, rather than including finer surface details may be sufficient. To test whether a depth-based display could be used to navigate a small obstacle course, we built a real-time head-mounted display with a depth camera and software to detect the distance to nearby objects. Distance was represented as brightness on a low-resolution display positioned close to the eyes without the benefit focussing optics. A set of sighted participants were monitored as they learned to use this display to navigate the course. All were able to do so, and time and velocity rapidly improved with practise with no increase in the number of collisions. In a second experiment a cohort of severely sight-impaired individuals of varying aetiologies performed a search task using a similar low-resolution head-mounted display. The majority of participants were able to use the display to respond to objects in their central and peripheral fields at a similar rate to sighted controls. We conclude that the skill to use a depth-based display for obstacle avoidance can be rapidly acquired and the simplified nature of the display may appropriate for the development of an aid for sight-impaired individuals. PMID:23844067

  7. A depth-based head-mounted visual display to aid navigation in partially sighted individuals.

    PubMed

    Hicks, Stephen L; Wilson, Iain; Muhammed, Louwai; Worsfold, John; Downes, Susan M; Kennard, Christopher

    2013-01-01

    Independent navigation for blind individuals can be extremely difficult due to the inability to recognise and avoid obstacles. Assistive techniques such as white canes, guide dogs, and sensory substitution provide a degree of situational awareness by relying on touch or hearing but as yet there are no techniques that attempt to make use of any residual vision that the individual is likely to retain. Residual vision can restricted to the awareness of the orientation of a light source, and hence any information presented on a wearable display would have to limited and unambiguous. For improved situational awareness, i.e. for the detection of obstacles, displaying the size and position of nearby objects, rather than including finer surface details may be sufficient. To test whether a depth-based display could be used to navigate a small obstacle course, we built a real-time head-mounted display with a depth camera and software to detect the distance to nearby objects. Distance was represented as brightness on a low-resolution display positioned close to the eyes without the benefit focussing optics. A set of sighted participants were monitored as they learned to use this display to navigate the course. All were able to do so, and time and velocity rapidly improved with practise with no increase in the number of collisions. In a second experiment a cohort of severely sight-impaired individuals of varying aetiologies performed a search task using a similar low-resolution head-mounted display. The majority of participants were able to use the display to respond to objects in their central and peripheral fields at a similar rate to sighted controls. We conclude that the skill to use a depth-based display for obstacle avoidance can be rapidly acquired and the simplified nature of the display may appropriate for the development of an aid for sight-impaired individuals. PMID:23844067

  8. Computer-aided navigation in secondary reconstruction of post-traumatic deformities of the zygoma.

    PubMed

    Watzinger, F; Wanschitz, F; Wagner, A; Enislidis, G; Millesi, W; Baumann, A; Ewers, R

    1997-08-01

    Augmented reality technology was used in 5 patients for secondary reconstruction of post-traumatic unilateral deformities of the zygomaticomaxillary complex. Three electromagnetic sensors interfaced to a computer-aided navigation system (ARTMA Biomedical Inc.) were utilized. The computer navigation procedure was planned by drawing graphic lines on the CT scan at the level of the zygomatic arch, representing the outer surface of the zygoma. The desired position of the displaced zygoma was planned by mirroring from the healthy side, using a virtual mid-sagittal plane. These virtual graphics were presented intraoperatively on a TV monitor and also on the surgeon's see-through head-mounted display. Correct reduction was assumed when the virtual line representing the position of the zygoma before the osteotomy reached the virtual line defined preoperatively as the desired position. The advantages of the technique presented are that a complete exposure of the zygomatic bone is no longer necessary, and coronal and subciliary incisions may be avoided unless enophthalmos correction has to be carried out, which was in fact necessary in 2 patients. The results of zygomatic reconstruction have been satisfactory in all 5 patients. PMID:9268898

  9. 21 CFR 874.3950 - Transcutaneous air conduction hearing aid system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Conduction Hearing Aid System (TACHAS); Guidance for Industry and FDA.” See § 874.1 for the availability of... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Transcutaneous air conduction hearing aid system... Transcutaneous air conduction hearing aid system. (a) Identification. A transcutaneous air conduction hearing...

  10. The Effects of Spatial Visualization Ability and Graphical Navigational Aids on Cognitive Load and Learning from Web-Based Instruction

    ERIC Educational Resources Information Center

    Morozov, Andrew

    2009-01-01

    This study contributes to research investigating the effects of individual differences and online instructional design on learning. Learning performance was compared across three hypertext formats incorporating different navigational aids. The hierarchical map represented the physical structure of the hypertext in one condition, while the network…

  11. Development of a computer program data base of a navigation aid environment for simulated IFR flight and landing studies

    NASA Technical Reports Server (NTRS)

    Bergeron, H. P.; Haynie, A. T.; Mcdede, J. B.

    1980-01-01

    A general aviation single pilot instrument flight rule simulation capability was developed. Problems experienced by single pilots flying in IFR conditions were investigated. The simulation required a three dimensional spatial navaid environment of a flight navigational area. A computer simulation of all the navigational aids plus 12 selected airports located in the Washington/Norfolk area was developed. All programmed locations in the list were referenced to a Cartesian coordinate system with the origin located at a specified airport's reference point. All navigational aids with their associated frequencies, call letters, locations, and orientations plus runways and true headings are included in the data base. The simulation included a TV displayed out-the-window visual scene of country and suburban terrain and a scaled model runway complex. Any of the programmed runways, with all its associated navaids, can be referenced to a runway on the airport in this visual scene. This allows a simulation of a full mission scenario including breakout and landing.

  12. 6-DOF Pose Estimation of a Robotic Navigation Aid by Tracking Visual and Geometric Features

    PubMed Central

    Ye, Cang; Hong, Soonhac; Tamjidi, Amirhossein

    2015-01-01

    This paper presents a 6-DOF Pose Estimation (PE) method for a Robotic Navigation Aid (RNA) for the visually impaired. The RNA uses a single 3D camera for PE and object detection. The proposed method processes the camera’s intensity and range data to estimates the camera’s egomotion that is then used by an Extended Kalman Filter (EKF) as the motion model to track a set of visual features for PE. A RANSAC process is employed in the EKF to identify inliers from the visual feature correspondences between two image frames. Only the inliers are used to update the EKF’s state. The EKF integrates the egomotion into the camera’s pose in the world coordinate system. To retain the EKF’s consistency, the distance between the camera and the floor plane (extracted from the range data) is used by the EKF as the observation of the camera’s z coordinate. Experimental results demonstrate that the proposed method results in accurate pose estimates for positioning the RNA in indoor environments. Based on the PE method, a wayfinding system is developed for localization of the RNA in a home environment. The system uses the estimated pose and the floorplan to locate the RNA user in the home environment and announces the points of interest and navigational commands to the user through a speech interface. Note to Practitioners This work was motivated by the limitations of the existing navigation technology for the visually impaired. Most of the existing methods use a point/line measurement sensor for indoor object detection. Therefore, they lack capability in detecting 3D objects and positioning a blind traveler. Stereovision has been used in recent research. However, it cannot provide reliable depth data for object detection. Also, it tends to produce a lower localization accuracy because its depth measurement error quadratically increases with the true distance. This paper suggests a new approach for navigating a blind traveler. The method uses a single 3D time

  13. Using APEX to Model Anticipated Human Error: Analysis of a GPS Navigational Aid

    NASA Technical Reports Server (NTRS)

    VanSelst, Mark; Freed, Michael; Shefto, Michael (Technical Monitor)

    1997-01-01

    The interface development process can be dramatically improved by predicting design facilitated human error at an early stage in the design process. The approach we advocate is to SIMULATE the behavior of a human agent carrying out tasks with a well-specified user interface, ANALYZE the simulation for instances of human error, and then REFINE the interface or protocol to minimize predicted error. This approach, incorporated into the APEX modeling architecture, differs from past approaches to human simulation in Its emphasis on error rather than e.g. learning rate or speed of response. The APEX model consists of two major components: (1) a powerful action selection component capable of simulating behavior in complex, multiple-task environments; and (2) a resource architecture which constrains cognitive, perceptual, and motor capabilities to within empirically demonstrated limits. The model mimics human errors arising from interactions between limited human resources and elements of the computer interface whose design falls to anticipate those limits. We analyze the design of a hand-held Global Positioning System (GPS) device used for radical and navigational decisions in small yacht recalls. The analysis demonstrates how human system modeling can be an effective design aid, helping to accelerate the process of refining a product (or procedure).

  14. GPS navigation algorithms for Autonomous Airborne Refueling of Unmanned Air Vehicles

    NASA Astrophysics Data System (ADS)

    Khanafseh, Samer Mahmoud

    Unmanned Air Vehicles (UAVs) have recently generated great interest because of their potential to perform hazardous missions without risking loss of life. If autonomous airborne refueling is possible for UAVs, mission range and endurance will be greatly enhanced. However, concerns about UAV-tanker proximity, dynamic mobility and safety demand that the relative navigation system meets stringent requirements on accuracy, integrity, and continuity. In response, this research focuses on developing high-performance GPS-based navigation architectures for Autonomous Airborne Refueling (AAR) of UAVs. The AAR mission is unique because of the potentially severe sky blockage introduced by the tanker. To address this issue, a high-fidelity dynamic sky blockage model was developed and experimentally validated. In addition, robust carrier phase differential GPS navigation algorithms were derived, including a new method for high-integrity reacquisition of carrier cycle ambiguities for recently-blocked satellites. In order to evaluate navigation performance, world-wide global availability and sensitivity covariance analyses were conducted. The new navigation algorithms were shown to be sufficient for turn-free scenarios, but improvement in performance was necessary to meet the difficult requirements for a general refueling mission with banked turns. Therefore, several innovative methods were pursued to enhance navigation performance. First, a new theoretical approach was developed to quantify the position-domain integrity risk in cycle ambiguity resolution problems. A mechanism to implement this method with partially-fixed cycle ambiguity vectors was derived, and it was used to define tight upper bounds on AAR navigation integrity risk. A second method, where a new algorithm for optimal fusion of measurements from multiple antennas was developed, was used to improve satellite coverage in poor visibility environments such as in AAR. Finally, methods for using data-link extracted

  15. History of the technological development of air conduction hearing aids.

    PubMed

    Mudry, A; Dodelé, L

    2000-06-01

    This was a study of the history of the technological development of air conduction hearing aids, and a review of international literature on the subject. The technological evolution of amplification devices, from their origin to the present day, can be divided into seven distinct periods: the period of sound collectors, the period of hearing devices constructed from carbon, the period of vacuum tubes, the transistor period, the period of integrated circuits, the microprocessor period and the period of digital hearing instruments. Throughout these different stages, hearing instruments have progressively developed reaching their present state. The current era is itself undergoing constant development and change. With the introduction of new technologies, we expect that the rate of change will increase rapidly in the future.

  16. Computer-aided conceptual design of Air Cushion Vehicles

    NASA Astrophysics Data System (ADS)

    Band, E. G. U.; Lavis, D. R.

    This paper describes the development and use of a computer-aided design tool which has been used to explore preferred options for amphibious Air-Cushion Vehicle (ACV) and Surface-Effect Ship (SES) designs in support of U.S. Navy and U.S. Army programs. The tool, referred to as the ACV Design Synthesis Model (ADSM), is an interactive computer program which provides a description of feasible ACV or SES concepts that could be developed, by a competent design team, to perform the mission described by the input parameters. The paper discusses how the program was used to explore parametrically the design of a range of self-propelled hoverbarges to meet requirements of the U.S. Army Logistics Over the Shore (LOTS) phases of an amphibious landing. Examples of results are presented to illustrate the method used in determining design and performance trade-offs.

  17. Decision-Aiding and Optimization for Vertical Navigation of Long-Haul Aircraft

    NASA Technical Reports Server (NTRS)

    Patrick, Nicholas J. M.; Sheridan, Thomas B.

    1996-01-01

    different airspace design and air traffic management policies. A decision aid is proposed which would combine the pilot's notion of optimility with the GA-based optimization, provide the pilot with a number of alternative pareto-optimal trajectories, and allow him to consider un-modelled attributes and constraints in choosing among them. A solution to the problem of displaying alternatives in a multi-attribute decision space is also presented.

  18. Decision-Aiding and Optimization for Vertical Navigation of Long-Haul Aircraft

    NASA Technical Reports Server (NTRS)

    Patrick, Nicholas J. M.; Sheridan, Thomas B.

    1996-01-01

    different airspace design and air traffic management policies. A decision aid is proposed which would combine the pilot's notion of optimality with the GA-based optimization, provide the pilot with a number of alternative pareto-optimal trajectories, and allow him to consider unmodelled attributes and constraints in choosing among them. A solution to the problem of displaying alternatives in a multi-attribute decision space is also presented.

  19. A study of mercuric oxide and zinc-air battery life in hearing aids.

    PubMed

    Sparkes, C; Lacey, N K

    1997-09-01

    The requirement to phase out mercuric oxide (mercury) batteries on environmental grounds has led to the widespread introduction of zinc-air technology. The possibility arises that high drain hearing aids may not be adequately catered for by zinc-air cells, leading to poor performance. This study investigated the hearing aid user's ability to perceive differences between zinc-air and mercury cells in normal everyday usage. The data was collected for 100 experienced hearing aid users in field trials. Users report 50 per cent greater life for zinc-air cells in high power aids and 28 per cent in low power aids. The average life of the zinc-air cells range from 15 days in high power to 34 days in low power aids. Users are able to perceive a difference in sound quality in favour of zinc-air cells for low and medium power aids. The hearing aid population is not disadvantaged by phasing out mercury cells. PMID:9373545

  20. Users' Evaluations of Four Electronic Travel Aids Aimed at Navigation for Persons Who Are Visually Impaired

    ERIC Educational Resources Information Center

    Roentgen, Uta R.; Gelderblom, Gert Jan; de Witte, Luc P.

    2011-01-01

    Eighteen persons with visual impairments evaluated four systematically selected navigation systems. Their performance on 11 tasks, provided ratings, satisfaction on seven aspects of the assistive devices, and explanatory comments show generally valuable functionality and usability, as well as individual marked preferences for various features of…

  1. 75 FR 25794 - Regulated Navigation Area: Red Bull Air Race World Championship, Upper New York Bay, Lower Hudson...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-10

    ..., 2008, issue of the Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA08 Regulated Navigation Area: Red Bull Air Race World... State Park, New Jersey and Ellis Island, New Jersey and New York for the Red Bull Air Race...

  2. Feature and Pose Constrained Visual Aided Inertial Navigation for Computationally Constrained Aerial Vehicles

    NASA Technical Reports Server (NTRS)

    Williams, Brian; Hudson, Nicolas; Tweddle, Brent; Brockers, Roland; Matthies, Larry

    2011-01-01

    A Feature and Pose Constrained Extended Kalman Filter (FPC-EKF) is developed for highly dynamic computationally constrained micro aerial vehicles. Vehicle localization is achieved using only a low performance inertial measurement unit and a single camera. The FPC-EKF framework augments the vehicle's state with both previous vehicle poses and critical environmental features, including vertical edges. This filter framework efficiently incorporates measurements from hundreds of opportunistic visual features to constrain the motion estimate, while allowing navigating and sustained tracking with respect to a few persistent features. In addition, vertical features in the environment are opportunistically used to provide global attitude references. Accurate pose estimation is demonstrated on a sequence including fast traversing, where visual features enter and exit the field-of-view quickly, as well as hover and ingress maneuvers where drift free navigation is achieved with respect to the environment.

  3. LIDAR-Aided Inertial Navigation with Extended Kalman Filtering for Pinpoint Landing

    NASA Technical Reports Server (NTRS)

    Busnardo, David M.; Aitken, Matthew L.; Tolson, Robert H.; Pierrottet, Diego; Amzajerdian, Farzin

    2011-01-01

    In support of NASA s Autonomous Landing and Hazard Avoidance Technology (ALHAT) project, an extended Kalman filter routine has been developed for estimating the position, velocity, and attitude of a spacecraft during the landing phase of a planetary mission. The proposed filter combines measurements of acceleration and angular velocity from an inertial measurement unit (IMU) with range and Doppler velocity observations from an onboard light detection and ranging (LIDAR) system. These high-precision LIDAR measurements of distance to the ground and approach velocity will enable both robotic and manned vehicles to land safely and precisely at scientifically interesting sites. The filter has been extensively tested using a lunar landing simulation and shown to improve navigation over flat surfaces or rough terrain. Experimental results from a helicopter flight test performed at NASA Dryden in August 2008 demonstrate that LIDAR can be employed to significantly improve navigation based exclusively on IMU integration.

  4. Loosely Coupled GPS-Aided Inertial Navigation System for Range Safety

    NASA Technical Reports Server (NTRS)

    Heatwole, Scott; Lanzi, Raymond J.

    2010-01-01

    The Autonomous Flight Safety System (AFSS) aims to replace the human element of range safety operations, as well as reduce reliance on expensive, downrange assets for launches of expendable launch vehicles (ELVs). The system consists of multiple navigation sensors and flight computers that provide a highly reliable platform. It is designed to ensure that single-event failures in a flight computer or sensor will not bring down the whole system. The flight computer uses a rules-based structure derived from range safety requirements to make decisions whether or not to destroy the rocket.

  5. Computer program for design and performance analysis of navigation-aid power systems. Program documentation. Volume 1: Software requirements document

    NASA Technical Reports Server (NTRS)

    Goltz, G.; Kaiser, L. M.; Weiner, H.

    1977-01-01

    A computer program has been developed for designing and analyzing the performance of solar array/battery power systems for the U.S. Coast Guard Navigational Aids. This program is called the Design Synthesis/Performance Analysis (DSPA) Computer Program. The basic function of the Design Synthesis portion of the DSPA program is to evaluate functional and economic criteria to provide specifications for viable solar array/battery power systems. The basic function of the Performance Analysis portion of the DSPA program is to simulate the operation of solar array/battery power systems under specific loads and environmental conditions. This document establishes the software requirements for the DSPA computer program, discusses the processing that occurs within the program, and defines the necessary interfaces for operation.

  6. 75 FR 997 - Record of Decision (ROD) on the U.S. Coast Guard Long Range Aids to Navigation (Loran-C) Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-07

    ... SECURITY Coast Guard Record of Decision (ROD) on the U.S. Coast Guard Long Range Aids to Navigation (Loran-C) Program AGENCY: Coast Guard, DHS. ACTION: Notice of availability. SUMMARY: The Department of Homeland Security (DHS), United States Coast Guard (USCG), announces the availability of the Record...

  7. Air-Flow Navigated Crystal Growth for TIPS Pentacene-Based Organic Thin-Film Transistors

    SciTech Connect

    He, Zhengran; Chen, Jihua; Sun, Zhenzhong; Szulczewski, Greg; Li, Dawen

    2012-01-01

    6,13-bis(triisopropylsilylethynyl)pentacene (TIPS pentacene) is a promising active channel material of organic thin-film transistors (OTFTs) due to its solubility, stability, and high mobility. However, the growth of TIPS pentacene crystals is intrinsically anisotropic and thus leads to significant variation in the performance of OTFTs. In this paper, air flow is utilized to effectively reduce the TIPS pentacene crystal anisotropy and enhance performance consistency in OTFTs, and the resulted films are examined with optical microscopy, grazing-incidence X-ray diffraction, and thin-film transistor measurements. Under air-flow navigation (AFN), TIPS pentacene drop-cast from toluene solution has been observed to form thin films with improved crystal orientation and increased areal coverage on substrates, which subsequently lead to a four-fold increase of average hole mobility and one order of magnitude enhancement in performance consistency defined by the ratio of average mobility to the standard deviation of the field-effect mobilities.

  8. Satellite-aided evaluation of population exposure to air pollution

    USGS Publications Warehouse

    Todd, William J.; George, Anthony J.; Bryant, Nevin A.

    1979-01-01

    The Clean Air Act Amendments of 1977 set schedules for states to implement regional, spatial assessments of air quality impacts. Accordingly, the U.S. Environmental Protection Agency recently published guidelines for quantifying population exposure to adverse air quality impact by using air quality and population data by census tracts. Our research complements the EPA guidelines in that it demonstrates the ability to determine population exposure to air pollution through computer processing that utilizes Landsat satellite-derived land use information. Three variables-a 1985 estimate of total suspended particulates for 2-km2 grid cells, Landsat-derived residential land cover data for 0.45-ha cells, and population totals for census tracts-were spatially registered and cross-tabulated to produce tabular and map products illustrating relative air quality exposure for residential population by 2-km2 cells. It would cost $20,000 to replicate our analysis for an area similar in size to the 4000-km2 Portland area. Once completed, the spatially fine, computer-compatible air quality and population data are amenable to the timely and efficient generation of population-at-risk tabular and map information on a continuous or periodic basis.

  9. Satellite-aided evaluation of population exposure to air pollution

    NASA Technical Reports Server (NTRS)

    Todd, W. J.; George, A. J., Jr.; Bryant, N. A.

    1979-01-01

    The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.

  10. The Global Framework for Providing Information about Volcanic-Ash Hazards to International Air Navigation

    NASA Astrophysics Data System (ADS)

    Romero, R. W.; Guffanti, M.

    2009-12-01

    The International Civil Aviation Organization (ICAO) created the International Airways Volcano Watch (IAVW) in 1987 to establish a requirement for international dissemination of information about airborne ash hazards to safe air navigation. The IAVW is a set of operational protocols and guidelines that member countries agree to follow in order to implement a global, multi-faceted program to support the strategy of ash-cloud avoidance. Under the IAVW, the elements of eruption reporting, ash-cloud detecting, and forecasting expected cloud dispersion are coordinated to culminate in warnings sent to air traffic controllers, dispatchers, and pilots about the whereabouts of ash clouds. Nine worldwide Volcanic Ash Advisory Centers (VAAC) established under the IAVW have the responsibility for detecting the presence of ash in the atmosphere, primarily by looking at imagery from civilian meteorological satellites, and providing advisories about the location and movement of ash clouds to aviation meteorological offices and other aviation users. Volcano Observatories also are a vital part of the IAVW, as evidenced by the recent introduction of a universal message format for reporting the status of volcanic activity, including precursory unrest, to aviation users. Since 2003, the IAVW has been overseen by a standing group of scientific, technical, and regulatory experts that assists ICAO in the development of standards and other regulatory material related to volcanic ash. Some specific problems related to the implementation of the IAVW include: the lack of implementation of SIGMET (warning to aircraft in flight) provisions and delayed notifications of volcanic eruptions. Expected future challenges and developments involve the improvement in early notifications of volcanic eruptions, the consolidation of the issuance of SIGMETs, and the possibility of determining a “safe” concentration of volcanic ash.

  11. Vertical Navigation Control Laws and Logic for the Next Generation Air Transportation System

    NASA Technical Reports Server (NTRS)

    Hueschen, Richard M.; Khong, Thuan H.

    2013-01-01

    A vertical navigation (VNAV) outer-loop control system was developed to capture and track the vertical path segments of energy-efficient trajectories that are being developed for high-density operations in the evolving Next Generation Air Transportation System (NextGen). The VNAV control system has a speed-on-elevator control mode to pitch the aircraft for tracking a calibrated airspeed (CAS) or Mach number profile and a path control mode for tracking the VNAV altitude profile. Mode control logic was developed for engagement of either the speed or path control modes. The control system will level the aircraft to prevent it from flying through a constraint altitude. A stability analysis was performed that showed that the gain and phase margins of the VNAV control system significantly exceeded the design gain and phase margins. The system performance was assessed using a six-deg-of-freedom non-linear transport aircraft simulation and the performance is illustrated with time-history plots of recorded simulation data.

  12. Prospective memory in an air traffic control simulation: external aids that signal when to act.

    PubMed

    Loft, Shayne; Smith, Rebekah E; Bhaskara, Adella

    2011-03-01

    At work and in our personal life we often need to remember to perform intended actions at some point in the future, referred to as Prospective Memory. Individuals sometimes forget to perform intentions in safety-critical work contexts. Holding intentions can also interfere with ongoing tasks. We applied theories and methods from the experimental literature to test the effectiveness of external aids in reducing prospective memory error and costs to ongoing tasks in an air traffic control simulation. Participants were trained to accept and hand-off aircraft and to detect aircraft conflicts. For the prospective memory task, participants were required to substitute alternative actions for routine actions when accepting target aircraft. Across two experiments, external display aids were provided that presented the details of target aircraft and associated intended actions. We predicted that aids would only be effective if they provided information that was diagnostic of target occurrence, and in this study, we examined the utility of aids that directly cued participants when to allocate attention to the prospective memory task. When aids were set to flash when the prospective memory target aircraft needed to be accepted, prospective memory error and costs to ongoing tasks of aircraft acceptance and conflict detection were reduced. In contrast, aids that did not alert participants specifically when the target aircraft were present provided no advantage compared to when no aids were used. These findings have practical implications for the potential relative utility of automated external aids for occupations where individuals monitor multi-item dynamic displays. PMID:21443381

  13. 21 CFR 874.3950 - Transcutaneous air conduction hearing aid system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3950... occluding the ear canal. The device consists of an air conduction hearing aid attached to a surgically... ear canal. (b) Classification. Class II (special controls). The special control for this device is...

  14. 21 CFR 874.3950 - Transcutaneous air conduction hearing aid system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3950... occluding the ear canal. The device consists of an air conduction hearing aid attached to a surgically... ear canal. (b) Classification. Class II (special controls). The special control for this device is...

  15. 21 CFR 874.3305 - Wireless air-conduction hearing aid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Wireless air-conduction hearing aid. 874.3305 Section 874.3305 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3305 Wireless...

  16. 21 CFR 874.3305 - Wireless air-conduction hearing aid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Wireless air-conduction hearing aid. 874.3305 Section 874.3305 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3305 Wireless...

  17. 21 CFR 874.3950 - Transcutaneous air conduction hearing aid system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3950... occluding the ear canal. The device consists of an air conduction hearing aid attached to a surgically... ear canal. (b) Classification. Class II (special controls). The special control for this device is...

  18. 21 CFR 874.3305 - Wireless air-conduction hearing aid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Wireless air-conduction hearing aid. 874.3305 Section 874.3305 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3305 Wireless...

  19. 21 CFR 874.3950 - Transcutaneous air conduction hearing aid system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3950... system is a wearable sound-amplifying device intended to compensate for impaired hearing without occluding the ear canal. The device consists of an air conduction hearing aid attached to a...

  20. Using an Empirical Model of Human Turning Motion to Aid Heading Estimation in a Personal Navigation System

    NASA Astrophysics Data System (ADS)

    Jakel, Thomas

    With the adoption of Global Navigation Satellite Systems in smart phones, soldier equipment, and emergency responder navigation systems users have realized the usefulness of low cost Personal Navigation Systems. The state-of-the-art Personal Navigation System is a unit that fuses information based on external references with a low cost IMU. Due to the size, weight, power, and cost constraints imposed on a pedestrian navigation systems as well as current IMU performance limitations, the gyroscopes used to determine heading exhibit significant drift limiting the performance of the navigation system. In this thesis biomechanical signals are used to predict the onset of pedestrian turning motion. Experimental data from eight subjects captured in a gait laboratory using a Vicon motion tracking unit is used for validation. The analysis of experimental data shows the heading computed by turn prediction augmented integration is more accurate than open loop gyro integration alone.

  1. Civil air navigation using GNSS enhanced by wide area satellite based augmentation systems

    NASA Astrophysics Data System (ADS)

    Dautermann, Thomas

    2014-05-01

    Advancement in augmented satellite navigation enables a new class of instrument approach procedures for aircraft. These approaches are based on regional augmentation systems which broadcast corrections via a geostationary satellite. The enhanced GNSS navigation solution using the corrections from the satellite provides the necessary accuracy and integrity to perform approaches with vertical and lateral angular guidance to a given runway threshold. This enables cost effective and simple procedure generation with low descent minima even for small airports. Moreover, it supports high precision en-route navigation and future high precision flight guidance applications.

  2. Human Factors Considerations for Performance-Based Navigation

    NASA Technical Reports Server (NTRS)

    Barhydt, Richard; Adams, Catherine A.

    2006-01-01

    A transition toward a performance-based navigation system is currently underway in both the United States and around the world. Performance-based navigation incorporates Area Navigation (RNAV) and Required Navigation Performance (RNP) procedures that do not rely on the location of ground-based navigation aids. These procedures offer significant benefits to both operators and air traffic managers. Under sponsorship from the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA) has undertaken a project to document human factors issues that have emerged during RNAV and RNP operations and propose areas for further consideration. Issues were found to include aspects of air traffic control and airline procedures, aircraft systems, and procedure design. Major findings suggest the need for human factors-specific instrument procedure design guidelines. Ongoing industry and government activities to address air-ground communication terminology, procedure design improvements, and chart-database commonality are strongly encouraged.

  3. Verification and Validation of Numerical Models for Air/Water Flow on Coastal and Navigation Fluid-Structure Interaction Applications

    NASA Astrophysics Data System (ADS)

    Kees, C. E.; Farthing, M.; Dimakopoulos, A.; DeLataillade, T.

    2015-12-01

    Performance analysis and optimization of coastal and navigation structures is becoming feasible due to recent improvements in numerical methods for multiphase flows and the steady increase in capacity and availability of high performance computing resources. Now that the concept of fully three-dimensional air/water flow modelling for real world engineering analysis is achieving acceptance by the wider engineering community, it is critical to expand careful comparative studies on verification,validation, benchmarking, and uncertainty quantification for the variety of competing numerical methods that are continuing to evolve. Furthermore, uncertainty still remains about the relevance of secondary processes such as surface tension, air compressibility, air entrainment, and solid phase (structure) modelling so that questions about continuum mechanical theory and mathematical analysis of multiphase flow are still required. Two of the most popular and practical numerical approaches for large-scale engineering analysis are the Volume-Of-Fluid (VOF) and Level Set (LS) approaches. In this work we will present a publically available verification and validation test set for air-water-structure interaction problems as well as computational and physical model results including a hybrid VOF-LS method, traditional VOF methods, and Smoothed Particle Hydrodynamics (SPH) results. The test set repository and test problem formats will also be presented in order to facilitate future comparative studies and reproduction of scientific results.

  4. 78 FR 68861 - Certain Navigation Products, Including GPS Devices, Navigation and Display Systems, Radar Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-15

    ..., Navigational Aids, Mapping Systems and Related Software; Institution of Investigation Pursuant to 19 U.S.C... and display systems, radar systems, navigational aids, mapping systems and related software by reason... products, including GPS devices, navigation and display systems, radar systems, navigational aids,...

  5. Autocalibrating vision guided navigation of unmanned air vehicles via tactical monocular cameras in GPS denied environments

    NASA Astrophysics Data System (ADS)

    Celik, Koray

    This thesis presents a novel robotic navigation strategy by using a conventional tactical monocular camera, proving the feasibility of using a monocular camera as the sole proximity sensing, object avoidance, mapping, and path-planning mechanism to fly and navigate small to medium scale unmanned rotary-wing aircraft in an autonomous manner. The range measurement strategy is scalable, self-calibrating, indoor-outdoor capable, and has been biologically inspired by the key adaptive mechanisms for depth perception and pattern recognition found in humans and intelligent animals (particularly bats), designed to assume operations in previously unknown, GPS-denied environments. It proposes novel electronics, aircraft, aircraft systems, systems, and procedures and algorithms that come together to form airborne systems which measure absolute ranges from a monocular camera via passive photometry, mimicking that of a human-pilot like judgement. The research is intended to bridge the gap between practical GPS coverage and precision localization and mapping problem in a small aircraft. In the context of this study, several robotic platforms, airborne and ground alike, have been developed, some of which have been integrated in real-life field trials, for experimental validation. Albeit the emphasis on miniature robotic aircraft this research has been tested and found compatible with tactical vests and helmets, and it can be used to augment the reliability of many other types of proximity sensors.

  6. From Medical Image Computing to Computer Aided Intervention: Development of a Research Interface for Image Guided Navigation

    PubMed Central

    Papademetris, Xenophon; DeLorenzo, Christine; Flossmann, Sven; Neff, Markus; Vives, Kenneth P.; Spencer, Dennis D.; Staib, Lawrence H.; Duncan, James S.

    2009-01-01

    Background This paper describes the development and application of a research interface to integrate research image analysis software with a commercial image guided surgery navigation system. This interface enables bi-directional transfer of data such as images, visualizations and tool positions in real time. Methods We describe both the design and the application programming interface of the research interface, as well as show the function of an example client program. The resulting interface provides a practical and versatile link for bringing image analysis research techniques into the operating room (OR). Results We present examples from the successful use of this research interface in both phantom experiments and in real neurosurgeries. In particular we demonstrate that the integrated dual-computer system achieves tool tracking performance that is comparable to the more typical single-computer scenario. Conclusions Network interfaces for this type are viable solutions for the integration of commercial image-guided navigation systems and research software. PMID:19301361

  7. Usability and Navigability of an HIV/AIDS Internet Intervention for Adolescents in a Resource Limited Setting

    PubMed Central

    Ybarra, Michele; Biringi, Ruth; Prescott, Tonya; Bull, Sheana S.

    2012-01-01

    Use of Internet is growing in Sub Saharan Africa. Evidence of computer and Internet effectiveness for reduction in risk behaviors associated with HIV shown in U.S. settings has yet to be replicated in Africa. We describe the development, usability and navigability testing of an Internet-based HIV prevention program for secondary school students in Uganda, called CyberSenga. For this work, we used four data collection activities, including observation of (a) computer skills and (b) navigation, (c) focus group discussions, and (d) field assessments to document comprehension and usability of program content. We document limited skills among students, but youth with basic computers skills were able to navigate the program after instruction. Youth were most interested in activities with more interaction. Field-testing illustrated the importance of using a stand-alone electrical source during program delivery. This work suggests delivery of Internet-based health promotion content in Africa requires attention to user preparedness and literacy, bandwidth, Internet connection, and electricity. PMID:22918136

  8. IEEE PLANS '90 - Position Location and Navigation Symposium, Las Vegas, NV, Mar. 20-23, 1990, Record

    NASA Astrophysics Data System (ADS)

    Various papers on position, location, and navigation are presented. The general topics addressed include: space-based navigation systems; inertial sensor development; other radio navigation system technologies; surveying, mapping, and digital electronics technology; positioning, pointing, and stabilization of space systems; inertial systems development and applications; integrated communicaiton/navigration systems and standard avionics; application of statistical filtering to navigation technology; GPS applications and equipment in civil, governmental, and commercial areas. Also discussed are: integrated navigation and targeting systems; civil aviation and marine navigation/traffic control; geodesy, gravity measurement, and earth reference systems; GPS military applications and equipment; integrated aircraft navigation and flight control; land vehicle navigation, positioning, and information systems; differential GPS; GPS/inertial navigation; terrain aided air vehicle navigation.

  9. Statistical Entry, Descent, and Landing Flight Reconstruction with Flush Air Data System Observations using Inertial Navigation and Monte Carlo Techniques

    NASA Astrophysics Data System (ADS)

    Lugo, Rafael Andres

    A method is introduced to consider flush air data system (FADS) pressures using a technique based on inertial navigation to reconstruct the trajectory of an atmospheric entry vehicle. The approach augments the recently-developed Inertial Navigation Statistical Trajectory and Atmosphere Reconstruction (INSTAR), which is an extension of inertial navigation that provides statistical uncertainties by utilizing Monte Carlo dispersion techniques and is an alternative to traditional statistical approaches to entry, descent, and landing trajectory and atmosphere reconstruction. The method is demonstrated using flight data from the Mars Science Laboratory (MSL) entry vehicle, which contained an inertial measurement unit and a flush air data system called the Mars Entry Atmospheric Data System (MEADS). An MSL trajectory and atmosphere solution that was updated using landing site location in INSTAR is first presented. This solution and corresponding uncertainties, which were obtained from Monte Carlo dispersions, are then used in a minimum variance algorithm to obtain aerodynamic estimates and uncertainties from the MEADS observations. MEADS-derived axial force coefficient and freestream density estimates and uncertainties are also derived from the minimum variance solutions independent of the axial force coefficients derived from computation fluid dynamics (CFD), which have relatively high a priori uncertainty. Results from probabilistic analyses of the solutions are also presented. This dissertation also introduces a method to consider correlated CFD uncertainties in INSTAR. From a priori CFD uncertainties, CFD force and pressure coefficients are dispersed in a Monte Carlo sense and carried over into the reconstructions. An analysis of the subsequent effects on the trajectory, atmosphere, and aerodynamic estimates and statistics is presented. Trajectory, atmospheric, and aerodynamic estimates compare favorably to extended Kalman filter solutions obtained by the MSL

  10. A Common Communications, Navigation and Surveillance Infrastructure for Accommodating Space Vehicles in the Next Generation Air Transportation System

    NASA Technical Reports Server (NTRS)

    VanSuetendael, RIchard; Hayes, Alan; Birr, Richard

    2008-01-01

    Suborbital space flight and space tourism are new potential markets that could significantly impact the National Airspace System (NAS). Numerous private companies are developing space flight capabilities to capture a piece of an emerging commercial space transportation market. These entrepreneurs share a common vision that sees commercial space flight as a profitable venture. Additionally, U.S. space exploration policy and national defense will impose significant additional demands on the NAS. Air traffic service providers must allow all users fair access to limited airspace, while ensuring that the highest levels of safety, security, and efficiency are maintained. The FAA's Next Generation Air Transportation System (NextGen) will need to accommodate spacecraft transitioning to and from space through the NAS. To accomplish this, space and air traffic operations will need to be seamlessly integrated under some common communications, navigation and surveillance (CNS) infrastructure. As part of NextGen, the FAA has been developing the Automatic Dependent Surveillance Broadcast (ADS-B) which utilizes the Global Positioning System (GPS) to track and separate aircraft. Another key component of NextGen, System-Wide Information Management/ Network Enabled Operations (SWIM/NEO), is an open architecture network that will provide NAS data to various customers, system tools and applications. NASA and DoD are currently developing a space-based range (SBR) concept that also utilizes GPS, communications satellites and other CNS assets. The future SBR will have very similar utility for space operations as ADS-B and SWIM has for air traffic. Perhaps the FAA, NASA, and DoD should consider developing a common space-based CNS infrastructure to support both aviation and space transportation operations. This paper suggests specific areas of research for developing a CNS infrastructure that can accommodate spacecraft and other new types of vehicles as an integrated part of NextGen.

  11. A genetic-algorithm-aided stochastic optimization model for regional air quality management under uncertainty.

    PubMed

    Qin, Xiaosheng; Huang, Guohe; Liu, Lei

    2010-01-01

    A genetic-algorithm-aided stochastic optimization (GASO) model was developed in this study for supporting regional air quality management under uncertainty. The model incorporated genetic algorithm (GA) and Monte Carlo simulation techniques into a general stochastic chance-constrained programming (CCP) framework and allowed uncertainties in simulation and optimization model parameters to be considered explicitly in the design of least-cost strategies. GA was used to seek the optimal solution of the management model by progressively evaluating the performances of individual solutions. Monte Carlo simulation was used to check the feasibility of each solution. A management problem in terms of regional air pollution control was studied to demonstrate the applicability of the proposed method. Results of the case study indicated the proposed model could effectively communicate uncertainties into the optimization process and generate solutions that contained a spectrum of potential air pollutant treatment options with risk and cost information. Decision alternatives could be obtained by analyzing tradeoffs between the overall pollutant treatment cost and the system-failure risk due to inherent uncertainties.

  12. HIV, AIDS, and the Future

    MedlinePlus

    ... Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV, AIDS, and the Future Past Issues / Summer 2009 Table ... and your loved ones from HIV/AIDS. The AIDS Memorial Quilt In 1987, a total of 1, ...

  13. Occupational and public field exposure from communication, navigation, and radar systems used for air traffic control.

    PubMed

    Joseph, Wout; Goeminne, Francis; Vermeeren, Günter; Verloock, Leen; Martens, Luc

    2012-12-01

    Electromagnetic exposure (occupational and general public) to 14 types of air traffic control (ATC) systems is assessed. Measurement methods are proposed for in situ exposure assessment of these ATC systems. In total, 50 sites are investigated at 1,073 locations in the frequency range of 255 kHz to 24 GHz. For all installations, typical and maximal exposure values for workers and the general public are provided. Two of the 14 types of systems, Non-Directional Beacons (NDB) (up to 881.6 V m) and Doppler Very High Frequency (VHF) Omni-directional Range (DVOR) (up to 92.3 V m), exhibited levels requiring recommended minimum distances such that the ICNIRP reference levels are not exceeded. Cumulative exposure of all present radiofrequency (RF) sources is investigated, and it is concluded that the ATC source dominates the total exposure in its neighborhood. PMID:23111522

  14. Occupational and public field exposure from communication, navigation, and radar systems used for air traffic control.

    PubMed

    Joseph, Wout; Goeminne, Francis; Vermeeren, Günter; Verloock, Leen; Martens, Luc

    2012-12-01

    Electromagnetic exposure (occupational and general public) to 14 types of air traffic control (ATC) systems is assessed. Measurement methods are proposed for in situ exposure assessment of these ATC systems. In total, 50 sites are investigated at 1,073 locations in the frequency range of 255 kHz to 24 GHz. For all installations, typical and maximal exposure values for workers and the general public are provided. Two of the 14 types of systems, Non-Directional Beacons (NDB) (up to 881.6 V m) and Doppler Very High Frequency (VHF) Omni-directional Range (DVOR) (up to 92.3 V m), exhibited levels requiring recommended minimum distances such that the ICNIRP reference levels are not exceeded. Cumulative exposure of all present radiofrequency (RF) sources is investigated, and it is concluded that the ATC source dominates the total exposure in its neighborhood.

  15. Design of a multi-sensor sonar system for indoor range measurement as a navigational aid for the blind.

    PubMed

    Choudhury, Maroof H; Barreto, Armando

    2003-01-01

    This paper reports the methodology for the design of a sonar-based ranging and guidance system. The intended application of the system is to help a blind person avoid obstacles as he/she navigates his/her environment. Six sonar transceivers are arranged radially on a headgear worn by the user. The transceivers detect discrete range data at discrete-time sampling instances. A panoramic map of the environment is generated from the discrete-space sensory data. The paper emphasizes the challenges faced during the measurement of omnidirectional ranging information in indoor environments. Situations have been identified where erroneous range readings are generated due to channel cross talk caused by echo bouncing off multiple surfaces. Several sonar control and measurement schemes were developed and tested to avoid these situations. The results and performance of these different control schemes are compared in this paper. A microcontroller-based system commands the sonar ping sequences, acquires the echo return times and computes the ranges. The set of range data is transmitted to a PC, which utilizes the information to build a spatialized audio map of the surrounding obstacles. The hardware and software layout for the system are described in this paper.

  16. GPS-aided inertial technology and navigation-based photogrammetry for aerial mapping the San Andreas fault system

    USGS Publications Warehouse

    Sanchez, Richard D.; Hudnut, Kenneth W.

    2004-01-01

    Aerial mapping of the San Andreas Fault System can be realized more efficiently and rapidly without ground control and conventional aerotriangulation. This is achieved by the direct geopositioning of the exterior orientation of a digital imaging sensor by use of an integrated Global Positioning System (GPS) receiver and an Inertial Navigation System (INS). A crucial issue to this particular type of aerial mapping is the accuracy, scale, consistency, and speed achievable by such a system. To address these questions, an Applanix Digital Sensor System (DSS) was used to examine its potential for near real-time mapping. Large segments of vegetation along the San Andreas and Cucamonga faults near the foothills of the San Bernardino and San Gabriel Mountains were burned to the ground in the California wildfires of October-November 2003. A 175 km corridor through what once was a thickly vegetated and hidden fault surface was chosen for this study. Both faults pose a major hazard to the greater Los Angeles metropolitan area and a near real-time mapping system could provide information vital to a post-disaster response.

  17. "AID"-ing Academic Program Evaluation: The "Automatic Interaction Detector" as Analysis Tool. AIR 1984 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Bloom, Allan M.; And Others

    The use of of the Automatic Interaction Detector (program AID3 of the OSIRIS statistical package) to study a university program is discussed. The performance of students who took general physics lecture and laboratory concurrently is compared to the performance of those who took them separately. Five years of data are analyzed, covering 1,997…

  18. Reducing prospective memory error and costs in simulated air traffic control: External aids, extending practice, and removing perceived memory requirements.

    PubMed

    Loft, Shayne; Chapman, Melissa; Smith, Rebekah E

    2016-09-01

    In air traffic control (ATC), forgetting to perform deferred actions-prospective memory (PM) errors-can have severe consequences. PM demands can also interfere with ongoing tasks (costs). We examined the extent to which PM errors and costs were reduced in simulated ATC by providing extended practice, or by providing external aids combined with extended practice, or by providing external aids combined with instructions that removed perceived memory requirements. Participants accepted/handed-off aircraft and detected conflicts. For the PM task, participants were required to substitute alternative actions for routine actions when accepting aircraft. In Experiment 1, when no aids were provided, PM errors and costs were not reduced by practice. When aids were provided, costs observed early in practice were eliminated with practice, but residual PM errors remained. Experiment 2 provided more limited practice with aids, but instructions that did not frame the PM task as a "memory" task led to high PM accuracy without costs. Attention-allocation policies that participants set based on expected PM demands were modified as individuals were increasingly exposed to reliable aids, or were given instructions that removed perceived memory requirements. These findings have implications for the design of aids for individuals who monitor multi-item dynamic displays. (PsycINFO Database Record PMID:27608067

  19. Serendipity, International Cooperation and Navigational Aids: A History of Radio Echo Sounding (RES) Technologies, 1958-1979

    NASA Astrophysics Data System (ADS)

    Turchetti, S.; Dean, K.; Naylor, S.; Siegert, M. J.

    2006-12-01

    This paper explores the history of RES and examines major technological advances that fostered the use of this technique in the sub-glacial exploration of Antarctica. The paper will especially focus on three themes: the role played by accidental discoveries in the origins of RES; the importance of international collaboration in its technological development; and the need of establishing new technological networks in the deployment of RES apparatus during Antarctic missions. The origins of RES can be traced back to two important -albeit accidental- findings. First, during post-war US military operations in the Antarctic radio altimeters produced gross errors in height indication. Furthermore, during the IGY ionospheric research and sounding was hampered by interference due to bottom echoes. These serendipitous events helped to figure out that the Antarctic ice was transparent to certain frequencies, and therefore new radio technologies could be used to sound what lay beneath it. The establishment of the Scientific Committee on Antarctic Research (SCAR) and the Antarctic Treaty (AT) provided a new international framework vital to the development of RES technologies. This allowed researchers from different countries to come together and discuss important technological features for the first time. At a technical level, the setting up of international experiments (such as those of 1963 and 1964 in Greenland) gave an opportunity for experts from different countries to compare the performance of new RES apparatus. At a political level, the parallel debate within the AT community on the allocation of Antarctic radio frequencies helped radio engineers to work out ways to circumvent interference with radio communications. Finally, the deployment of RES equipment in Antarctic exploration relied upon a number of technological aids to improve the potential and accuracy of geophysical sounding. The use of new aircrafts, guidance systems, and computers proved vital in many

  20. An architecture for integrating distributed and cooperating knowledge-based Air Force decision aids

    NASA Technical Reports Server (NTRS)

    Nugent, Richard O.; Tucker, Richard W.

    1988-01-01

    MITRE has been developing a Knowledge-Based Battle Management Testbed for evaluating the viability of integrating independently-developed knowledge-based decision aids in the Air Force tactical domain. The primary goal for the testbed architecture is to permit a new system to be added to a testbed with little change to the system's software. Each system that connects to the testbed network declares that it can provide a number of services to other systems. When a system wants to use another system's service, it does not address the server system by name, but instead transmits a request to the testbed network asking for a particular service to be performed. A key component of the testbed architecture is a common database which uses a relational database management system (RDBMS). The RDBMS provides a database update notification service to requesting systems. Normally, each system is expected to monitor data relations of interest to it. Alternatively, a system may broadcast an announcement message to inform other systems that an event of potential interest has occurred. Current research is aimed at dealing with issues resulting from integration efforts, such as dealing with potential mismatches of each system's assumptions about the common database, decentralizing network control, and coordinating multiple agents.

  1. 33 CFR 64.31 - Determination of hazard to navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Determination of hazard to navigation. 64.31 Section 64.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARKING OF STRUCTURES, SUNKEN VESSELS AND OTHER OBSTRUCTIONS...

  2. 33 CFR 64.31 - Determination of hazard to navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Determination of hazard to navigation. 64.31 Section 64.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARKING OF STRUCTURES, SUNKEN VESSELS AND OTHER OBSTRUCTIONS...

  3. 33 CFR 66.10-35 - Navigation lights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a...

  4. 33 CFR 66.10-35 - Navigation lights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a...

  5. 33 CFR 66.10-35 - Navigation lights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a...

  6. 33 CFR 66.10-35 - Navigation lights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Navigation lights....

  7. 33 CFR 66.10-35 - Navigation lights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navigation lights....

  8. Flight Test Result for the Ground-Based Radio Navigation System Sensor with an Unmanned Air Vehicle.

    PubMed

    Jang, Jaegyu; Ahn, Woo-Guen; Seo, Seungwoo; Lee, Jang Yong; Park, Jun-Pyo

    2015-01-01

    The Ground-based Radio Navigation System (GRNS) is an alternative/backup navigation system based on time synchronized pseudolites. It has been studied for some years due to the potential vulnerability issue of satellite navigation systems (e.g., GPS or Galileo). In the framework of our study, a periodic pulsed sequence was used instead of the randomized pulse sequence recommended as the RTCM (radio technical commission for maritime services) SC (special committee)-104 pseudolite signal, as a randomized pulse sequence with a long dwell time is not suitable for applications requiring high dynamics. This paper introduces a mathematical model of the post-correlation output in a navigation sensor, showing that the aliasing caused by the additional frequency term of a periodic pulsed signal leads to a false lock (i.e., Doppler frequency bias) during the signal acquisition process or in the carrier tracking loop of the navigation sensor. We suggest algorithms to resolve the frequency false lock issue in this paper, relying on the use of a multi-correlator. A flight test with an unmanned helicopter was conducted to verify the implemented navigation sensor. The results of this analysis show that there were no false locks during the flight test and that outliers stem from bad dilution of precision (DOP) or fluctuations in the received signal quality.

  9. Flight Test Result for the Ground-Based Radio Navigation System Sensor with an Unmanned Air Vehicle

    PubMed Central

    Jang, Jaegyu; Ahn, Woo-Guen; Seo, Seungwoo; Lee, Jang Yong; Park, Jun-Pyo

    2015-01-01

    The Ground-based Radio Navigation System (GRNS) is an alternative/backup navigation system based on time synchronized pseudolites. It has been studied for some years due to the potential vulnerability issue of satellite navigation systems (e.g., GPS or Galileo). In the framework of our study, a periodic pulsed sequence was used instead of the randomized pulse sequence recommended as the RTCM (radio technical commission for maritime services) SC (special committee)-104 pseudolite signal, as a randomized pulse sequence with a long dwell time is not suitable for applications requiring high dynamics. This paper introduces a mathematical model of the post-correlation output in a navigation sensor, showing that the aliasing caused by the additional frequency term of a periodic pulsed signal leads to a false lock (i.e., Doppler frequency bias) during the signal acquisition process or in the carrier tracking loop of the navigation sensor. We suggest algorithms to resolve the frequency false lock issue in this paper, relying on the use of a multi-correlator. A flight test with an unmanned helicopter was conducted to verify the implemented navigation sensor. The results of this analysis show that there were no false locks during the flight test and that outliers stem from bad dilution of precision (DOP) or fluctuations in the received signal quality. PMID:26569251

  10. Flight Test Result for the Ground-Based Radio Navigation System Sensor with an Unmanned Air Vehicle.

    PubMed

    Jang, Jaegyu; Ahn, Woo-Guen; Seo, Seungwoo; Lee, Jang Yong; Park, Jun-Pyo

    2015-01-01

    The Ground-based Radio Navigation System (GRNS) is an alternative/backup navigation system based on time synchronized pseudolites. It has been studied for some years due to the potential vulnerability issue of satellite navigation systems (e.g., GPS or Galileo). In the framework of our study, a periodic pulsed sequence was used instead of the randomized pulse sequence recommended as the RTCM (radio technical commission for maritime services) SC (special committee)-104 pseudolite signal, as a randomized pulse sequence with a long dwell time is not suitable for applications requiring high dynamics. This paper introduces a mathematical model of the post-correlation output in a navigation sensor, showing that the aliasing caused by the additional frequency term of a periodic pulsed signal leads to a false lock (i.e., Doppler frequency bias) during the signal acquisition process or in the carrier tracking loop of the navigation sensor. We suggest algorithms to resolve the frequency false lock issue in this paper, relying on the use of a multi-correlator. A flight test with an unmanned helicopter was conducted to verify the implemented navigation sensor. The results of this analysis show that there were no false locks during the flight test and that outliers stem from bad dilution of precision (DOP) or fluctuations in the received signal quality. PMID:26569251

  11. HIV / AIDS: An Unequal Burden

    MedlinePlus

    ... Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV / AIDS: An Unequal Burden Past Issues / Summer 2009 Table ... Victoria Cargill talks to students about HIV and AIDS at the opening of a National Library of ...

  12. 32 CFR 644.3 - Navigation projects.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Navigation projects. 644.3 Section 644.3... ESTATE HANDBOOK Project Planning Civil Works § 644.3 Navigation projects. (a) Land to be acquired in fee... for channel improvements, navigation pools, navigation aids, and spoil disposal areas for...

  13. 32 CFR 644.3 - Navigation projects.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Navigation projects. 644.3 Section 644.3 National... HANDBOOK Project Planning Civil Works § 644.3 Navigation projects. (a) Land to be acquired in fee. All... channel improvements, navigation pools, navigation aids, and spoil disposal areas for future...

  14. 32 CFR 644.3 - Navigation projects.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Navigation projects. 644.3 Section 644.3 National... HANDBOOK Project Planning Civil Works § 644.3 Navigation projects. (a) Land to be acquired in fee. All... channel improvements, navigation pools, navigation aids, and spoil disposal areas for future...

  15. 32 CFR 644.3 - Navigation Projects.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... Requirements for navigation aids should be coordinated by the District Engineer with the local Coast Guard... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should...

  16. 32 CFR 644.3 - Navigation projects.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintenance. Requirements for navigation aids should be coordinated by the District Engineer with the local..., and temporary construction and borrow areas. (3) In navigation-only projects, the right to...

  17. 78 FR 19277 - Navigation Safety Advisory Council; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... SECURITY United States Coast Guard Navigation Safety Advisory Council; Meeting AGENCY: United States Coast Guard, DHS. ACTION: Notice of Federal Advisory Committee meeting: correction. SUMMARY: The Navigation...; navigation regulations and equipment; routing measures; marine information; diving safety; and aids...

  18. Space shuttle navigation analysis

    NASA Technical Reports Server (NTRS)

    Jones, H. L.; Luders, G.; Matchett, G. A.; Sciabarrasi, J. E.

    1976-01-01

    A detailed analysis of space shuttle navigation for each of the major mission phases is presented. A covariance analysis program for prelaunch IMU calibration and alignment for the orbital flight tests (OFT) is described, and a partial error budget is presented. The ascent, orbital operations and deorbit maneuver study considered GPS-aided inertial navigation in the Phase III GPS (1984+) time frame. The entry and landing study evaluated navigation performance for the OFT baseline system. Detailed error budgets and sensitivity analyses are provided for both the ascent and entry studies.

  19. Effectiveness of Air Drying and Magnification Methods for Detecting Initial Caries on Occlusal Surfaces Using Three Different Diagnostic Aids.

    PubMed

    Goel, Deepti; Sandhu, Meera; Jhingan, Pulkit; Sachdev, Vinod

    2016-01-01

    Objective-The aim of this study was to assess the effect of magnification and air-drying on detection of carious lesion. Study Design-44 human extracted premolars were selected with sound occlusal surfaces without frank cavitation. The Diagnostic techniques used were Unaided visual examination, Magnifying Loupes (4.2×) and Stereomicroscope (10×, before and after air-drying) and then the teeth were sectioned bucco-lingually and both the surfaces were examined under Stereomicroscope (50×) to assess the presence or absence of carious lesion in the pit and fissures. The scores were compared to obtain Cohen's kappa coefficient (Reproducibility) and subjected to the Friedman Test and Paired t test. Sensitivity, specificity and positive predictive value used to assess accuracy. Results-On Statistical analysis, visual examination before and after air drying had highest specificity but lowest sensitivity compared to different diagnostic techniques. Magnifying loupes after air-drying had highest sensitivity and lowest specificity compared to other diagnostic techniques. Conclusion-Air drying combined with magnifying aids are cost-effective, reliable method for detection of early carious lesion. If used in pediatric clinical practice, any undesirable pain and discomfort to the patient due to invasive procedures and helps in employing preventive measures. PMID:27472570

  20. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  1. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  2. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  3. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  4. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  5. Assessing Pricing and Aid Strategies: Rethinking Planning and Evaluation Practices. AIR 1994 Annual Forum Paper.

    ERIC Educational Resources Information Center

    St. John, Edward P.

    This paper explores the need for a better understanding of the influences of prices and student aid on student enrollment and college budgets. The theory of net price has not been found to adequately explain changes in enrollment. Based on a critical review of recent research on student price response, this paper develops an alternative approach…

  6. Tuition Pricing and Aid Strategies: A Practical Approach. AIR 1994 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Fine, Paul L.

    This paper examines the applicability of net tuition revenue models for a highly selective, elite priced, private research university in the southern U.S. Pricing and aid strategies for this university seem to be driven by intuitive assumptions about the economy, market forces, needs-blind admissions, student satisfaction, net price…

  7. 33 CFR 74.01-15 - Charges for placement of temporary aids.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will...

  8. 33 CFR 74.01-15 - Charges for placement of temporary aids.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will...

  9. 33 CFR 74.01-15 - Charges for placement of temporary aids.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will...

  10. 33 CFR 74.01-15 - Charges for placement of temporary aids.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will...

  11. 33 CFR 74.01-15 - Charges for placement of temporary aids.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will...

  12. 76 FR 63934 - Navigation Safety Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ... of the Federal Register (73 FR 3316). Docket: For access to the docket to read documents or comments... measures, marine information, diving safety, and aids to navigation systems. The meeting will be open to... information, diving safety, and aids to navigation systems. Agenda The NAVSAC will meet to review, discuss...

  13. Methods of Optical Navigation

    NASA Technical Reports Server (NTRS)

    Owen, William M., Jr.

    2011-01-01

    Optical navigation is the use of onboard imaging to aid in the determination of the spacecraft trajectory and of the targets' ephemerides. Opnav techniques provide a direct measurement of the direction from a spacecraft to target bodies. Opnav data thus complement both radiometric tracking data (for instance, Doppler and range) and the groundbased astrometry which is used to determine the a priori ephemeris of the targets. We present the geometry and camera models which form the mathematical basis for optical navigation and some of the image processing techniques by which one can extract the optical observables--that is, the sample and line coordinates of images--from pictures.

  14. Planar array stack design aided by rapid prototyping in development of air-breathing PEMFC

    NASA Astrophysics Data System (ADS)

    Chen, Chen-Yu; Lai, Wei-Hsiang; Weng, Biing-Jyh; Chuang, Huey-Jan; Hsieh, Ching-Yuan; Kung, Chien-Chih

    The polymer electrolyte membrane fuel cell (PEMFC) is one of the most important research topics in the new and clean energy area. The middle or high power PEMFCs can be applied to the transportation or the distributed power system. But for the small power application, it is needed to match the power requirement of the product generally. On the other hand, the direct methanol fuel cell (DMFC) is one of the most common type that researchers are interested in, but recently the miniature or the micro-PEMFCs attract more attention due to their advantages of high open circuit voltage and high power density. The objective of this study is to develop a new air-breathing planar array fuel cell stacked from 10 cells made by rapid prototyping technology which has potential for fast commercial design, low cost manufacturing, and even without converters/inverters for the system. In this paper, the main material of flow field plates is acrylonitrile-butadiene-styrene (ABS) which allows the fuel cell be mass-manufactured by plastic injection molding technology. The rapid prototyping technology is applied to construct the prototype and verify the practicability of the proposed stack design. A 10-cell air-breathing miniature PEMFC stack with a volume of 6 cm × 6 cm × 0.9 cm is developed and tested. Its segmented membrane electrode assembly (MEA) is designed with the active surface area of 1.3 cm × 1.3 cm in each individual MEA. The platinum loading at anode and cathode are 0.2 mg cm -2 and 0.4 mg cm -2, respectively. Results show that the peak power densities of the parallel connected and serial connected stack are 99 mW cm -2 at 0.425 V and 92 mW cm -2 at 4.25 V, respectively under the conditions of 70 °C relative saturated humidity (i.e., dew point temperature), ambient temperature and free convection air. Besides, the stack performance is increased under forced convection. If the cell surface air is blown by an electric fan, the peak power densities of parallel connected and

  15. Analysis of air quality observations with the aid of the source-receptor relationship approach.

    PubMed

    Astitha, Marina; Kallos, George; Mihalopoulos, Nikos

    2005-04-01

    In this study, an attempt was made to analyze time series of air quality measurements (O3, SO2, SO4(2-), NOx) conducted at a remote place in the eastern Mediterranean (Finokalia at Crete Island in 1999) to obtain concrete information on potential contributions from emission sources. For the definition of a source-receptor relationship, advanced meteorological and dispersion models appropriate to identify "areas of influence" have been used. The model tools used are the Regional Atmospheric Modeling System and the Lagrangian-type particle dispersion model (forward and backward in time), with capabilities to derive influence functions and definition of "areas of influence." When high levels of pollutants have been measured at the remote location of Finokalia, particles are released from this location (receptor) and traced backward in time. The influence function derived from particle distributions characterizes dispersion conditions in the atmosphere and also provides information on potential contributions from emission sources within the modeling domain to this high concentration. As was shown in the simulation results, the experimental site of Finokalia in Crete is influenced during the selected case studies, primarily by pollutants emitted from the urban conglomerate of Athens. Secondarily, it is influenced by polluted air masses arriving from Italy and/or the Black Sea Region. For some specific cases, air pollutants monitored at Finokalia were possibly related to war activities in the West Balkan Region (Kosovo). PMID:15887895

  16. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  17. The scavenging of air pollutants by precipitation, and its estimation with the aid of weather radar

    NASA Astrophysics Data System (ADS)

    Jylha, Kirsti Tellervo

    2000-09-01

    Precipitation cleanses the air by capturing airborne pollutants and depositing them onto the ground. The efficiency of this process may be expressed by the fractional depletion rate of pollutant concentrations in the air, designated as the scavenging coefficient. It depends on the size distribution of the raindrops and snow crystals and is thereby related to quantities estimated by weather radar, namely, the radar reflectivity factor and the precipitation rate. On the other hand, there are no universal relationships between the scavenging coefficient and these two quantities; the relationships vary depending on the properties of the precipitation and pollutants. In the present thesis, a few estimates for them were derived theoretically and empirically, using in the latter case observations made in Finland either after the Chernobyl nuclear accident or during a wintertime case study near a coal-fired power plant. The greatest advantage in the use of weather radar in assessing precipitation scavenging arises from the fact that radar estimates the spatial distributions of precipitation in real time with a good spatial and temporal resolution. Radar software usually used to create displays of the precipitation rate can easily be modified to show distributions of the scavenging coefficient. Such images can provide valuable information about the areas where a substantial portion of the pollutants is deposited onto the ground or, alternatively, remains airborne. Based on the movement of the precipitation areas, it is also possible to make short-term forecasts of those areas most likely to be exposed to wet deposition. A network of radars may hence form an important part of a real-time monitoring and warning system that can be immediately effective in the event of an accidental releases of hazardous materials into the air.

  18. A mixed simulation and hardware-in-the-loop display and controller for autonomous sensing and navigation by unmanned air vehicles

    NASA Astrophysics Data System (ADS)

    Collins, Gaemus E.; Vegdahl, Philip S.; Riehl, James R.

    2007-04-01

    This paper describes our recent work combining a high-fidelity battlefield software simulaton, a suite of autonomous sensor and navigation control algorithms for unmanned air vehicles (UAVs), and a hardware-in-the-loop control interface. The complete system supports multiple real and simulated UAVs that search for and track multiple real and simulated targets. Targets communicate their real-time locations to the simulator through a wireless GPS link. Data from real target(s) is used to create target(s) in the simulation testbed that may exist alongside additional simulated targets. The navigation and video sensors onboard the UAVs are tasked (via another wireless link) by our control algorithm suite to search for and track targets that exist in the simulation. Video data is streamed to an image plane video tracker (IPVT), which produces detections that can be fed to a global tracker within the control suite. Routing and gimbal control algorithms use information from the global tracker to task the UAVs, thus completing an information feedback control loop. Additional sensors (such as the ground moving target indicator (GMTI) radar) can exist within the simulation and generate simulated detections to augment the tracking information obtained from the IPVT. Our simulator is part of Toyon's Simulation of the Locations and Attack of Mobile Enemy Missiles (SLAMEM (R)) tool. SLAMEM contains detailed models for ground targets, surveillance platforms, sensors, attack aircraft, UAVs, data exploitation, multi-source fusion, sensor retasking, and attack nomination. SLAMEM models road networks, foliage cover, populated regions, and terrain, using the terrain elevation data (DTED).

  19. National Institutes of Health, Office of AIDS Research

    MedlinePlus

    ... Contact Us Main Navigation for the Office of AIDS Research Homepage ABOUT OAR SCIENTIFIC AREAS STRATEGIC PLAN ... HIV/AIDS INFORMATION Welcome to the Office of AIDS Research. Welcome to the Office of AIDS Research ...

  20. National Institutes of Health, Office of AIDS Research

    MedlinePlus

    ... Us Main Navigation for the Office of AIDS Research Homepage ABOUT OAR SCIENTIFIC AREAS STRATEGIC PLAN NIH ... AIDS INFORMATION Welcome to the Office of AIDS Research. Welcome to the Office of AIDS Research Dr. ...

  1. Photonics aided ultra-wideband W-band signal generation and air space transmission

    NASA Astrophysics Data System (ADS)

    Li, Xinying; Yu, Jianjun

    2016-02-01

    We achieve several field trial demonstrations of ultra-wideband W-band millimeter-wave (mm-wave) signal generation and its long-distance air space transmission based on some enabling technologies and advanced devices. First, we demonstrated photonics generation and up to 1.7-km wireless delivery of 20-Gb/s polarization division multiplexing quadrature phase shift keying (PDM-QPSK) signal at W-band, adopting both optical and antenna polarization multiplexing. Then, we demonstrated photonics generation and up to 300-m wireless delivery of 80-Gb/s PDM-QPSK signal at W-band, adopting both optical and antenna polarization multiplexing as well as multi-band multiplexing. We also demonstrated photonics generation and up to 100-m wireless delivery of 100-Gb/s QPSK signal at W-band, adopting antenna polarization multiplexing.

  2. Space Shuttle Orbiter descent navigation

    NASA Technical Reports Server (NTRS)

    Montez, M. N.; Madden, M. F.

    1982-01-01

    The entry operational sequence (OPS 3) begins approximately 2 hours prior to the deorbit maneuver and continues through atmospheric entry, terminal area energy management (TAEM), approach and landing, and rollout. During this flight phase, the navigation state vector is estimated by the Space Shuttle Orbiter onboard navigation system. This estimate is computed using a six-element sequential Kalman filter, which blends inertial measurement unit (IMU) delta-velocity data with external navaid data. The external navaids available to the filter are tactical air navigation (TACAN), barometric altimeter, and microwave scan beam landing system (MSBLS). Attention is given to the functional design of the Orbiter navigation system, the descent navigation sensors and measurement processing, predicted Kalman gains, correlation coefficients, and current flights navigation performance.

  3. 75 FR 56538 - Air Products and Chemicals, Inc.; Analysis of Proposed Agreement Containing Consent Orders to Aid...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ... Products and Chemicals, Inc.; Analysis of Proposed Agreement Containing Consent Orders to Aid Public... practices or unfair methods of competition. The attached Analysis to Aid Public Comment describes both the... period of thirty (30) days. The following Analysis to Aid Public Comment describes the terms of...

  4. Potential applications of satellite navigation

    NASA Astrophysics Data System (ADS)

    Schaenzer, G.

    The applicability of Navstar GPS to civil air navigation is discussed. The accuracy of current air-navigation systems is reviewed; the basic principle and accuracy of GPS navigation are characterized; the relatively low cost of GPS receiving equipment is pointed out; and particular attention is given to hybrid systems combining GPS with inertial navigation. It is predicted that CAT III landings will be possible using such hybrid systems when the GPS satellites are fully deployed, even without access to the military GPS code. Techniques for GPS-based precision landings, reduced-noise landings, landings on parallel runways, control of taxiing maneuvers, and aircraft-based geodetic measurements are briefly described and illustrated with diagrams.

  5. The Effect of Types of Financial Aid on Student Persistence towards Graduation. AIR 1995 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Murdock, Tullise; And Others

    The relationship between student persistence and types of financial aid at a Jesuit comprehensive university was studied. Three freshmen cohorts (134 for 1989, 171 for 1990, and 131 for 1991) of 436 students were tracked through fall 1994. Attention was focused on nine financial aid variables, five additional noncategorical and six categorical…

  6. HIV / AIDS: Symptoms, Diagnosis, Prevention and Treatment

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV / AIDS: Symptoms , Diagnosis, Prevention and Treatment Past Issues / ... Most people who have become recently infected with HIV will not have any symptoms. They may, however, ...

  7. Selected bibliography of OMEGA, VLF and LF techniques applied to aircraft navigation systems

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A bibliography is presented which includes references to the OMEGA navigation system, very low frequencies, time-frequency measurements, air traffic control, radio navigation, and applications of OMEGA.

  8. 14 CFR 129.22 - Communication and navigation equipment for rotorcraft operations under VFR over routes navigated...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... rotorcraft operations under VFR over routes navigated by pilotage. 129.22 Section 129.22 Aeronautics and... and navigation equipment for rotorcraft operations under VFR over routes navigated by pilotage. (a) No foreign air carrier may operate a rotorcraft under VFR over routes that can be navigated by...

  9. 14 CFR 129.22 - Communication and navigation equipment for rotorcraft operations under VFR over routes navigated...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... rotorcraft operations under VFR over routes navigated by pilotage. 129.22 Section 129.22 Aeronautics and... and navigation equipment for rotorcraft operations under VFR over routes navigated by pilotage. (a) No foreign air carrier may operate a rotorcraft under VFR over routes that can be navigated by...

  10. 14 CFR 129.22 - Communication and navigation equipment for rotorcraft operations under VFR over routes navigated...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... rotorcraft operations under VFR over routes navigated by pilotage. 129.22 Section 129.22 Aeronautics and... and navigation equipment for rotorcraft operations under VFR over routes navigated by pilotage. (a) No foreign air carrier may operate a rotorcraft under VFR over routes that can be navigated by...

  11. 14 CFR 129.22 - Communication and navigation equipment for rotorcraft operations under VFR over routes navigated...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... rotorcraft operations under VFR over routes navigated by pilotage. 129.22 Section 129.22 Aeronautics and... and navigation equipment for rotorcraft operations under VFR over routes navigated by pilotage. (a) No foreign air carrier may operate a rotorcraft under VFR over routes that can be navigated by...

  12. 14 CFR 129.22 - Communication and navigation equipment for rotorcraft operations under VFR over routes navigated...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... rotorcraft operations under VFR over routes navigated by pilotage. 129.22 Section 129.22 Aeronautics and... and navigation equipment for rotorcraft operations under VFR over routes navigated by pilotage. (a) No foreign air carrier may operate a rotorcraft under VFR over routes that can be navigated by...

  13. Viking navigation

    NASA Technical Reports Server (NTRS)

    Oneil, W. J.; Rudd, R. P.; Farless, D. L.; Hildebrand, C. E.; Mitchell, R. T.; Rourke, K. H.; Euler, E. A.

    1979-01-01

    A comprehensive description of the navigation of the Viking spacecraft throughout their flight from Earth launch to Mars landing is given. The flight path design, actual inflight control, and postflight reconstruction are discussed in detail. The preflight analyses upon which the operational strategies and performance predictions were based are discussed. The inflight results are then discussed and compared with the preflight predictions and, finally, the results of any postflight analyses are presented.

  14. 33 CFR 144.01-30 - First-aid kit.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false First-aid kit. 144.01-30 Section 144.01-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-30 First-aid kit. On each manned platform a first-aid kit...

  15. Space shuttle entry and landing navigation analysis

    NASA Technical Reports Server (NTRS)

    Jones, H. L.; Crawford, B. S.

    1974-01-01

    A navigation system for the entry phase of a Space Shuttle mission which is an aided-inertial system which uses a Kalman filter to mix IMU data with data derived from external navigation aids is evaluated. A drag pseudo-measurement used during radio blackout is treated as an additional external aid. A comprehensive truth model with 101 states is formulated and used to generate detailed error budgets at several significant time points -- end-of-blackout, start of final approach, over runway threshold, and touchdown. Sensitivity curves illustrating the effect of variations in the size of individual error sources on navigation accuracy are presented. The sensitivity of the navigation system performance to filter modifications is analyzed. The projected overall performance is shown in the form of time histories of position and velocity error components. The detailed results are summarized and interpreted, and suggestions are made concerning possible software improvements.

  16. 14 CFR 125.51 - En route navigation facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false En route navigation facilities. 125.51... and Miscellaneous Requirements § 125.51 En route navigation facilities. (a) Except as provided in... any destination, refueling or alternate airports) unless suitable navigation aids are available...

  17. 14 CFR 121.121 - En route navigation facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false En route navigation facilities. 121.121... Operations § 121.121 En route navigation facilities. (a) Except as provided in paragraph (b) of this section... (including to any destination, refueling or alternate airports) unless suitable navigation aids are...

  18. 14 CFR 121.103 - En route navigation facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false En route navigation facilities. 121.103... § 121.103 En route navigation facilities. (a) Except as provided in paragraph (b) of this section, each... regular, provisional, refueling or alternate airports), that suitable navigation aids are available...

  19. 14 CFR 121.121 - En route navigation facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false En route navigation facilities. 121.121... Operations § 121.121 En route navigation facilities. (a) Except as provided in paragraph (b) of this section... (including to any destination, refueling or alternate airports) unless suitable navigation aids are...

  20. 14 CFR 121.121 - En route navigation facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false En route navigation facilities. 121.121... Operations § 121.121 En route navigation facilities. (a) Except as provided in paragraph (b) of this section... (including to any destination, refueling or alternate airports) unless suitable navigation aids are...

  1. 14 CFR 121.103 - En route navigation facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false En route navigation facilities. 121.103... § 121.103 En route navigation facilities. (a) Except as provided in paragraph (b) of this section, each... regular, provisional, refueling or alternate airports), that suitable navigation aids are available...

  2. 14 CFR 125.51 - En route navigation facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false En route navigation facilities. 125.51... and Miscellaneous Requirements § 125.51 En route navigation facilities. (a) Except as provided in... any destination, refueling or alternate airports) unless suitable navigation aids are available...

  3. 14 CFR 121.103 - En route navigation facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false En route navigation facilities. 121.103... § 121.103 En route navigation facilities. (a) Except as provided in paragraph (b) of this section, each... regular, provisional, refueling or alternate airports), that suitable navigation aids are available...

  4. 75 FR 6215 - Houston/Galveston Navigation Safety Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ... SECURITY Coast Guard Houston/Galveston Navigation Safety Advisory Committee AGENCY: Coast Guard, DHS. ACTION: Notice of meetings. SUMMARY: The Houston/Galveston Navigation Safety Advisory Committee... improvements, aids to navigation, area projects impacting safety on the Houston Ship Channel, and various...

  5. 14 CFR 125.51 - En route navigation facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false En route navigation facilities. 125.51... and Miscellaneous Requirements § 125.51 En route navigation facilities. (a) Except as provided in... any destination, refueling or alternate airports) unless suitable navigation aids are available...

  6. 14 CFR 121.103 - En route navigation facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false En route navigation facilities. 121.103... § 121.103 En route navigation facilities. (a) Except as provided in paragraph (b) of this section, each... regular, provisional, refueling or alternate airports), that suitable navigation aids are available...

  7. 14 CFR 121.121 - En route navigation facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false En route navigation facilities. 121.121... Operations § 121.121 En route navigation facilities. (a) Except as provided in paragraph (b) of this section... (including to any destination, refueling or alternate airports) unless suitable navigation aids are...

  8. 14 CFR 125.51 - En route navigation facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false En route navigation facilities. 125.51... and Miscellaneous Requirements § 125.51 En route navigation facilities. (a) Except as provided in... any destination, refueling or alternate airports) unless suitable navigation aids are available...

  9. BIBLIOGRAPHY OF TRAINING AIDS.

    ERIC Educational Resources Information Center

    MCKEONE, CHARLES J.

    THIS COMPILATION OF INSTRUCTIONAL AIDS FOR USE IN AIR-CONDITIONING AND REFRIGERATION TRAINING PROGRAMS CONTAINS LISTS OF VISUAL AND AUDIOVISUAL TRAINING AIDS AND GUEST LECTURERS AVAILABLE FROM MEMBER COMPANIES OF THE AIR-CONDITIONING AND REFRIGERATION INSTITUTE AS AN INDUSTRY SERVICE TO SCHOOL OFFICIALS INTERESTED IN CONDUCTING SUCH PROGRAMS. THE…

  10. INL Autonomous Navigation System

    SciTech Connect

    2005-03-30

    The INL Autonomous Navigation System provides instructions for autonomously navigating a robot. The system permits high-speed autonomous navigation including obstacle avoidance, waypoing navigation and path planning in both indoor and outdoor environments.

  11. Low cost omega navigation receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1974-01-01

    The development of a low cost Omega navigation receiver is discussed. Emphasis is placed on the completion and testing of a modular, multipurpose Omega receiver which utilizes a digital memory-aided, phase-locked loop to provide phase measurement data to a variety of applications interfaces. The functional units contained in the prototype device are described. The receiver is capable of receiving and storing phase measurements for up to eight Omega signals and computes two switch-selectable lines of position, displaying this navigation data in chart-recorded form.

  12. 77 FR 23114 - Modification, Revocation and Establishment of Air Traffic Service Routes; Windsor Locks Area; CT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ...) routes in the vicinity of Windsor Locks, CT (77 FR 20528). Subsequent to publication, an error was... on April 5, 2010 (77 FR 20528) (FR Doc. 2012-8183) for RNAV route T-300, is corrected under the..., due to the planned decommissioning of the Bradley VHF omnirange/tactical air navigation aid....

  13. Aircraft Instrument, Fire Protection, Warning, Communication, Navigation and Cabin Atmosphere Control System (Course Outline), Aviation Mechanics 3 (Air Frame): 9067.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to familiarize the student with manipulative skills and theoretical knowledge concerning aircraft instrument systems like major flight and engine instruments; fire protection and fire fighting systems; warning systems and navigation systems; aircraft cabin control systems, such as…

  14. Fundamentals of satellite navigation

    NASA Astrophysics Data System (ADS)

    Stiller, A. H.

    The basic operating principles and capabilities of conventional and satellite-based navigation systems for air, sea, and land vehicles are reviewed and illustrated with diagrams. Consideration is given to autonomous onboard systems; systems based on visible or radio beacons; the Transit, Cicada, Navstar-GPS, and Glonass satellite systems; the physical laws and parameters of satellite motion; the definition of time in satellite systems; and the content of the demodulated GPS data signal. The GPS and Glonass data format frames are presented graphically, and tables listing the GPS and Glonass satellites, their technical characteristics, and the (past or scheduled) launch dates are provided.

  15. Navigational Aids: The Phenomenology of Transformative Learning

    ERIC Educational Resources Information Center

    Mälkki, Kaisu; Green, Larry

    2014-01-01

    Although the notion of transformative learning points to a desirable destination for educational endeavors, the difficulty in the journey is often neglected. Our intention is to map the experiential micro-processes involved in transformative learning such that the phenomenon is illuminated from a first-person rather than third-person point of…

  16. ["Knowing about AIDS" and sexual precautions among low-income women from the southern area of Buenos Aires. Notes for defining prevention policies].

    PubMed

    Grimberg, M

    2001-01-01

    This study is part of a line of research on gender and prevention in a research program on the social construction of HIV/AIDS. We present the results of an ethnographic study among low-income women 15-35 years old in the southern area of Buenos Aires. The area has the highest number of HIV/AIDS cases and high poverty levels, extensive social degradation, and urban violence. According to our results, in the interface between "knowing about" and "behaving" there are complex processes involving stigmatized and gender-biased representations of HIV/AIDS as "other people's problem" and social and sexual relations permeated by gender stereotypes and roles. We believe that planning of prevention should be based on the consideration of overall social practices and specifically the characteristics of gender relations, prioritizing relational strategies between women and men and promoting critical reflection on the main nodes organizing daily life and active participation in the production of social relations and practices of reciprocity and equity. The increasingly precarious conditions in social life intensifies poor women's vulnerability and social interaction contexts that relate to the socioeconomic and symbolic role played by women.

  17. 3D Air Quality and the Clean Air Interstate Rule: Lagrangian Sampling of CMAQ Model Results to Aid Regional Accountability Metrics

    NASA Technical Reports Server (NTRS)

    Fairlie, T. D.; Szykman, Jim; Pierce, Robert B.; Gilliland, A. B.; Engel-Cox, Jill; Weber, Stephanie; Kittaka, Chieko; Al-Saadi, Jassim A.; Scheffe, Rich; Dimmick, Fred; Tikvart, Joe

    2008-01-01

    The Clean Air Interstate Rule (CAIR) is expected to reduce transport of air pollutants (e.g. fine sulfate particles) in nonattainment areas in the Eastern United States. CAIR highlights the need for an integrated air quality observational and modeling system to understand sulfate as it moves in multiple dimensions, both spatially and temporally. Here, we demonstrate how results from an air quality model can be combined with a 3d monitoring network to provide decision makers with a tool to help quantify the impact of CAIR reductions in SO2 emissions on regional transport contributions to sulfate concentrations at surface monitors in the Baltimore, MD area, and help improve decision making for strategic implementation plans (SIPs). We sample results from the Community Multiscale Air Quality (CMAQ) model using ensemble back trajectories computed with the NASA Langley Research Center trajectory model to provide Lagrangian time series and vertical profile information, that can be compared with NASA satellite (MODIS), EPA surface, and lidar measurements. Results are used to assess the regional transport contribution to surface SO4 measurements in the Baltimore MSA, and to characterize the dominant source regions for low, medium, and high SO4 episodes.

  18. Vision assisted aircraft lateral navigation

    NASA Astrophysics Data System (ADS)

    Mohideen, Mohamed Ibrahim; Ramegowda, Dinesh; Seiler, Peter

    2013-05-01

    Surface operation is currently one of the least technologically equipped phases of aircraft operation. The increased air traffic congestion necessitates more aircraft operations in degraded weather and at night. The traditional surface procedures worked well in most cases as airport surfaces have not been congested and airport layouts were less complex. Despite the best efforts of FAA and other safety agencies, runway incursions continue to occur frequently due to incorrect surface operation. Several studies conducted by FAA suggest that pilot induced error contributes significantly to runway incursions. Further, the report attributes pilot's lack of situational awareness - local (e.g., minimizing lateral deviation), global (e.g., traffic in the vicinity) and route (e.g., distance to next turn) - to the problem. An Enhanced Vision System (EVS) is one concept that is being considered to resolve these issues. These systems use on-board sensors to provide situational awareness under poor visibility conditions. In this paper, we propose the use of an Image processing based system to estimate the aircraft position and orientation relative to taxiway markings to use as lateral guidance aid. We estimate aircraft yaw angle and lateral offset from slope of the taxiway centerline and horizontal position of vanishing line. Unlike automotive applications, several cues such as aircraft maneuvers along assigned route with minimal deviations, clear ground markings, even taxiway surface, limited aircraft speed are available and enable us to implement significant algorithm optimizations. We present experimental results to show high precision navigation accuracy with sensitivity analysis with respect to camera mount, optics, and image processing error.

  19. Final-Approach Spacing Aids (FASA) evaluation for terminal-area, time-based air traffic control

    NASA Technical Reports Server (NTRS)

    Credeur, Leonard; Capron, William R.; Lohr, Gary W.; Crawford, Daniel J.; Tang, Dershuen A.; Rodgers, William G., Jr.

    1993-01-01

    A jointly funded (NASA/FAA) real-time simulation study was conducted at NASA Langley Research Center to gather comparative performance data among three candidate final-approach spacing aid (FASA) display formats. Several objective measures of controller performance and their display eye-scan behavior as well as subjective workload and rating questionnaires were used. For each of two representative pattern-speed procedures (a 170-knot procedure and a 210-knot procedure with speed control aiding), data were gathered, via twelve FAA controllers, using four final-controller display format conditions (manual/ARTS 3, graphic marker, DICE countdown, and centerline slot marker). Measured runway separations were more precise with both the graphic marker and DICE countdown formats than with the centerline slot marker and both (graphic and DICE) improved precision relative to the manual/ARTS 3 format. For three separate rating criteria, the subject controllers ranked the FASA formats in the same order: graphic marker, DICE countdown, and centerline slot marker. The increased precision measured with the 210-knot pattern-speed procedure may indicate the potential for the application of speed-control aiding where higher pattern speeds are practical after the base-to-final turn. Also presented are key FASA issues, a rationale for the formats selected for testing, and their description.

  20. 33 CFR 144.01-30 - First-aid kit.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false First-aid kit. 144.01-30 Section...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-30 First-aid kit. On each manned platform a first-aid kit approved by the Commandant or the U.S. Bureau of Mines shall...

  1. 33 CFR 144.01-30 - First-aid kit.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false First-aid kit. 144.01-30 Section...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-30 First-aid kit. On each manned platform a first-aid kit approved by the Commandant or the U.S. Bureau of Mines shall...

  2. 33 CFR 144.01-30 - First-aid kit.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false First-aid kit. 144.01-30 Section...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-30 First-aid kit. On each manned platform a first-aid kit approved by the Commandant or the U.S. Bureau of Mines shall...

  3. 33 CFR 144.01-30 - First-aid kit.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false First-aid kit. 144.01-30 Section...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-30 First-aid kit. On each manned platform a first-aid kit approved by the Commandant or the U.S. Bureau of Mines shall...

  4. Space Shuttle Orbiter entry through landing navigation

    NASA Technical Reports Server (NTRS)

    Ewell, J. J., Jr.

    1982-01-01

    The Space Shuttle Orbiter navigation system must be capable of determining its position and velocity throughout a variety of operational regimes. The design and operation of the entry through landing navigation system is described as it operates during a nominal end of mission from the orbital coasting phase throughout atmospheric flight and landing. Design and operation of the Kalman filter is described. Stabilization of the altitude channel prior to acquisition of external measurement data is described. Utilization of the Tactical Air Navigation (TACAN), barometric altimeter, and Microwave Scan Beam Landing System external measurement data is described. A comparison is made between predicted performance and the navigation accuracy observed during flight.

  5. An Ultrasonic and Air Pressure Sensing System for Detection of Behavior before Getting out of Bed Aided by Fuzzy Theory

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hayato; Nakajima, Hiroshi; Taniguchi, Kazuhiko; Kobashi, Syoji; Hata, Yutaka

    This paper proposes a sensing system for a behavior detection system using an ultrasonic oscillosensor and an air pressure sensor. The ultrasonic oscillosensor sensor has a cylindrical tank filled with water. It detects the vibration of the target object from the signal reflected from the water surface. This sensor can detect a biological vibration by setting to the bottom bed frame. The air pressure sensor consists of a polypropylene sheet and an air pressure sensor, and detects the pressure information by setting under the bed's mattress. An increase (decrease) in the load placed on the bed is detected by the increase (decrease) in the pressure of the air held in the tube attached to the sheet. We propose a behavior detection system using both sensors, complementally. The system recognizes three states (nobody in bed, keeping quiet in bed, moving in bed) using both sensors, and we detect the behavior before getting out of bed by recognized these states. Fuzzy logic plays a primary role in the system. As the fundamental experiment, we applied the system to five healthy volunteers, the system successfully recognized three states, and detected the behavior before getting out of bed. As the clinical experiment, we applied the system to four elderly patients with dementia, the system exactly detected the behavior before getting out of the bed with enough time for medical care support.

  6. A study of navigation in virtual space

    NASA Technical Reports Server (NTRS)

    Darken, Rudy; Sibert, John L.; Shumaker, Randy

    1994-01-01

    In the physical world, man has developed efficient methods for navigation and orientation. These methods are dependent on the high-fidelity stimuli presented by the environment. When placed in a virtual world which cannot offer stimuli of the same quality due to computing constraints and immature technology, tasks requiring the maintenance of position and orientation knowledge become laborious. In this paper, we present a representative set of techniques based on principles of navigation derived from real world analogs including human and avian navigation behavior and cartography. A preliminary classification of virtual worlds is presented based on the size of the world, the density of objects in the world, and the level of activity taking place in the world. We also summarize an informal study we performed to determine how the tools influenced the subjects' navigation strategies and behavior. We conclude that principles extracted from real world navigation aids such as maps can be seen to apply in virtual environments.

  7. GPS/INS generalized evaluation tool (GIGET) for the design and testing of integrated navigation systems

    NASA Astrophysics Data System (ADS)

    Gautier, Jennifer Denise

    GIGET, the GPS/INS Generalized Evaluation Tool, experimentally tests, evaluates, and compares navigation systems that combine the Global Positioning System (GPS) with Inertial Navigation Systems (INS). GPS is a precise and reliable navigation aid but can be susceptible to interference, multi-path, or other outages. An INS is very accurate over short periods, but its errors drift unbounded over time. Blending GPS with INS can remedy the performance issues of both. However, there are many types of integration methods, and sensors vary greatly, from the complex and expensive, to the simple and inexpensive. It is difficult to determine the best combination for any desired application; most of the integrated systems built to date have been point designs for very specific applications. GIGET aids in the selection of sensor combinations for any general application or set of requirements; hence, GIGET is the generalized way to evaluate the performance of integrated systems. GIGET is a combination of easily re-configurable hardware and analysis tools that can provide real-time comparisons of multiple integrated navigation systems. It includes a unique, multi-antenna GPS receiver and a tactical grade inertial measurement unit. GIGET is quickly outfitted onto a variety of vehicle platforms to experimentally test and compare navigation performance. In side-by-side experiments, GIGET compares loosely coupled and tightly coupled integrated navigation schemes blending navigation, tactical, or automotive grade inertial sensors with GPS. These results formulate a trade study to map previously uncharted territory of the GPS/INS space that trades accuracy and expense versus complexity of design. These GIGET results can be used to determine acceptable sensor quality in these integration methods for a variety of dynamic environments. As a demonstration of its utility as a hardware evaluation tool, GIGET is used to design a navigation system on the DragonFly Unmanned Air Vehicle (UAV

  8. Investigation Into the Use of Satellite Data in Aiding Characterization of Particulate Air Quality in the Atlanta, Georgia Metropolitan Area

    NASA Technical Reports Server (NTRS)

    Alston, Erica J.; Sokolik, Irina, N.; Doddridge, Bruce G.

    2011-01-01

    Poor air quality episodes occur often in metropolitan Atlanta, Georgia. The primary focus of this research is to assess the capability of satellites as a tool in characterizing air quality in Atlanta. Results indicate that intra-city PM2.5 concentrations show similar patterns as other U.S. urban areas, with the highest concentrations occurring within the city. Both PM2.5 and MODIS AOD show more increases in the summer than spring, yet MODIS AOD doubles in the summer unlike PM2.5. A majority of OMI AI is below 0.5. Using this value as an ambient measure of carbonaceous aerosols in the urban area, aerosol transport events can be identified. Our results indicate that MODIS AOD is well correlated with PM2.5 on a yearly and seasonal basis with correlation coefficients as high as 0.8 for Terra and 0.7 for Aqua. A possible alternative view of the PM2.5 and AOD relationship is seen through the use of AOD thresholds. These probabilistic thresholds provide a means to describe the AQI through the use of past AOD for a specific area. We use the NAAQS to classify the AOD into different AQI codes, and probabilistically determine thresholds of AOD that represent the majority of a specific AQI category. For example, the majority 80% of moderate AQI days have AOD values between 0.5 - 0.6. The development of thresholds could be a tool used to evaluate air quality from the use of satellites in regions where there are sparse ground-based measurements of PM2.5.

  9. Dynamic Transportation Navigation

    NASA Astrophysics Data System (ADS)

    Meng, Xiaofeng; Chen, Jidong

    Miniaturization of computing devices, and advances in wireless communication and sensor technology are some of the forces that are propagating computing from the stationary desktop to the mobile outdoors. Some important classes of new applications that will be enabled by this revolutionary development include intelligent traffic management, location-based services, tourist services, mobile electronic commerce, and digital battlefield. Some existing application classes that will benefit from the development include transportation and air traffic control, weather forecasting, emergency response, mobile resource management, and mobile workforce. Location management, i.e., the management of transient location information, is an enabling technology for all these applications. In this chapter, we present the applications of moving objects management and their functionalities, in particular, the application of dynamic traffic navigation, which is a challenge due to the highly variable traffic state and the requirement of fast, on-line computations.

  10. Apollo Onboard Navigation Techniques

    NASA Technical Reports Server (NTRS)

    Interbartolo, Michael

    2009-01-01

    This viewgraph presentation reviews basic navigation concepts, describes coordinate systems and identifies attitude determination techniques including Primary Guidance, Navigation and Control System (PGNCS) IMU management and Command and Service Module Stabilization and Control System/Lunar Module (LM) Abort Guidance System (AGS) attitude management. The presentation also identifies state vector determination techniques, including PGNCS coasting flight navigation, PGNCS powered flight navigation and LM AGS navigation.

  11. Testing Microwave Landing Systems With Satellite Navigation

    NASA Technical Reports Server (NTRS)

    Kiriazes, John J.

    1990-01-01

    Less time and equipment needed to perform tests. Satellite-based Global Positioning System (GPS) measures accuracy of microwave scanning-beam landing system (MSBLS) at airports used to support Shuttle landings. Provides time and three-dimensional information on position and velocity with unprecedented accuracy. Useful for testing other electronic navigation aids like LORAN, TACAN and microwave landing systems (MLS).

  12. An overview of optical gyroscopes for navigation

    NASA Astrophysics Data System (ADS)

    Mark, J. G.; Tazartes, D. A.

    1992-11-01

    In the 1980's, Ring Laser Gyroscopes (RLG) displaced the mechanical (spinning wheel) gyroscope as the angular sensor of choice for navigation. While the RLG remains the standard navigation grade instrument, several other optical gyroscopes have recently appeared. The multi oscillator (or four-mode gyro) represents a new generation in laser gyroscopes. Systems based on this technology are now being delivered for use on commercial and military aircraft. Another optical sensor, the fiber optic gyroscope (FOG) has been incorporated in inertial measurement units (IMU) and proved itself capable of AHRS (attitude and heading reference system) accuracy. This gyroscope should find many applications in aided navigation systems. Integrated FOG/GPS systems appear attractive as low cost navigators. This paper addresses technology involved in these optical gyroscopes and discusses their advantages and disadvantages in relation to present and future applications.

  13. Navigation for space shuttle approach and landing using an inertial navigation system augmented by data from a precision ranging system or a microwave scan beam landing guidance system

    NASA Technical Reports Server (NTRS)

    Mcgee, L. A.; Smith, G. L.; Hegarty, D. M.; Merrick, R. B.; Carson, T. M.; Schmidt, S. F.

    1970-01-01

    A preliminary study has been made of the navigation performance which might be achieved for the high cross-range space shuttle orbiter during final approach and landing by using an optimally augmented inertial navigation system. Computed navigation accuracies are presented for an on-board inertial navigation system augmented (by means of an optimal filter algorithm) with data from two different ground navigation aids; a precision ranging system and a microwave scanning beam landing guidance system. These results show that augmentation with either type of ground navigation aid is capable of providing a navigation performance at touchdown which should be adequate for the space shuttle. In addition, adequate navigation performance for space shuttle landing is obtainable from the precision ranging system even with a complete dropout of precision range measurements as much as 100 seconds before touchdown.

  14. Crawling Aid

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Institute for the Achievement of Human Potential developed a device known as the Vehicle for Initial Crawling (VIC); the acronym is a tribute to the crawler's inventor, Hubert "Vic" Vykukal; is an effective crawling aid. The VIC is used by brain injured children who are unable to crawl due to the problems of weight-bearing and friction, caused by gravity. It is a rounded plywood frame large enough to support the child's torso, leaving arms and legs free to move. On its underside are three aluminum discs through which air is pumped to create an air-bearing surface that has less friction than a film of oil. Upper side contains the connection to the air supply and a pair of straps which restrain the child and cause the device to move with him. VIC is used with the intent to recreate the normal neurological connection between brain and muscles. Over repetitive use of the device the child develops his arm and leg muscles as well as coordination. Children are given alternating therapy, with and without the VIC until eventually the device is no longer needed.

  15. Bayesian statistics and information fusion for GPS-denied navigation

    NASA Astrophysics Data System (ADS)

    Copp, Brian Lee

    It is well known that satellite navigation systems are vulnerable to disruption due to jamming, spoofing, or obstruction of the signal. The desire for robust navigation of aircraft in GPS-denied environments has motivated the development of feature-aided navigation systems, in which measurements of environmental features are used to complement the dead reckoning solution produced by an inertial navigation system. Examples of environmental features which can be exploited for navigation include star positions, terrain elevation, terrestrial wireless signals, and features extracted from photographic data. Feature-aided navigation represents a particularly challenging estimation problem because the measurements are often strongly nonlinear, and the quality of the navigation solution is limited by the knowledge of nuisance parameters which may be difficult to model accurately. As a result, integration approaches based on the Kalman filter and its variants may fail to give adequate performance. This project develops a framework for the integration of feature-aided navigation techniques using Bayesian statistics. In this approach, the probability density function for aircraft horizontal position (latitude and longitude) is approximated by a two-dimensional point mass function defined on a rectangular grid. Nuisance parameters are estimated using a hypothesis based approach (Multiple Model Adaptive Estimation) which continuously maintains an accurate probability density even in the presence of strong nonlinearities. The effectiveness of the proposed approach is illustrated by the simulated use of terrain referenced navigation and wireless time-of-arrival positioning to estimate a reference aircraft trajectory. Monte Carlo simulations have shown that accurate position estimates can be obtained in terrain referenced navigation even with a strongly nonlinear altitude bias. The integration of terrain referenced and wireless time-of-arrival measurements is described along with

  16. Microcomputers and astronomical navigation.

    NASA Astrophysics Data System (ADS)

    Robin-Jouan, Y.

    1996-04-01

    Experienced navigators remember ancient astronomical navigation and its limitations. Using microcomputers in small packages and selecting up-to-date efficient methods will overcome many of these limitations. Both features lead to focus on observations, and encourage an increase in their numbers. With no intention of competing with satellite navigation, sextant navigation in the open sea can then be accessed again by anybody. It can be considered for demonstrative use or as a complement to the GPS.

  17. HIV / AIDS

    MedlinePlus

    ... Marketing Share this: Main Content Area Understanding HIV/AIDS AIDS was first reported in the United States in ... and has since become a major worldwide epidemic. AIDS is caused by the human immunodeficiency virus, or ...

  18. Opportunity Egress Aid Contacts Soil

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image from the navigation camera on the Mars Exploration Rover Opportunity shows the rover's egress aid touching the martian soil at Meridiani Planum, Mars. The image was taken after the rear lander petal hyperextended in a manuever to tilt the lander forward. The maneuver pushed the front edge lower, placing the tips of the egress aids in the soil. The rover will drive straight ahead to exit the lander.

  19. 76 FR 2916 - Houston/Galveston Navigation Safety Advisory Committee; Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ... SECURITY Coast Guard Houston/Galveston Navigation Safety Advisory Committee; Meetings AGENCY: Coast Guard, DHS. ACTION: Notice of Meetings. SUMMARY: The Houston/Galveston Navigation Safety Advisory Committee... to discuss waterway improvements, aids to navigation, area projects impacting safety on the...

  20. An Agent-Based Model for Navigation Simulation in a Heterogeneous Environment

    ERIC Educational Resources Information Center

    Shanklin, Teresa A.

    2012-01-01

    Complex navigation (e.g. indoor and outdoor environments) can be studied as a system-of-systems problem. The model is made up of disparate systems that can aid a user in navigating from one location to another, utilizing whatever sensor system or information is available. By using intelligent navigation sensors and techniques (e.g. RFID, Wifi,…

  1. Onboard navigation rendezvous expert system

    NASA Astrophysics Data System (ADS)

    Kocen, Michelle

    The Onboard Navigation rendezvous expert system is designed to aid the ground flight controller in monitoring the shuttle onboard navigation system. The system is designed to keep track of the navigation sensors and relative state vectors. In addition, the system also keeps an event log and fills out forms usually handled by the flight controller. This expert system is one of the few rendezvous specific systems being developed for the Mission Control Center. The expert system has been in development for six years. Through these years the system has seen hardware, software, and personnel changes. Initial development was done by the Information Systems Directorate (ISD) and Mission Operations Directorate (MOD) at Johnson Space Center. As of October 1, 1991 the system has been turned over to MOD. The system is completely developed except for some minor adjustments to the user interface. The rule base is in the verification stage with total certification of the system due to be completed by May 1992. Test cases for verification are obtained by saving data used for flight controller integrated simulations. The actual data comes from both the shuttle mission simulator and the Mission Control Center Computer. So far no actual flight data has been available. This paper covers all aspects of the system from the development history to the current hardware, software, and use of the system.

  2. GPS/INS Enhancement for Land Navigation using Neural Network

    NASA Astrophysics Data System (ADS)

    Kaygisiz, Burak H.; Erkmen, Ismet; Erkmen, Aydan M.

    2004-05-01

    We propose in this paper a method to enhance the performance of a coupled global positioning/inertial navigation system (GPS/INS) for land navigation applications during GPS signal loss. Our method is based on the use of an artificial neural network (ANN) to intelligently aid the GPS/INS coupled navigation system in the absence of GPS signals. The proposed enhanced GPS/INS is tested in the dynamic environment of a land vehicle navigating around a closed path on the METU campus and we provide the results. Our GPS/INS+ANN system performance is thus demonstrated with a land trial.

  3. Investigation of Air Transportation Technology at Ohio University, 1989-1990

    NASA Technical Reports Server (NTRS)

    Lilley, Robert W.

    1990-01-01

    The activities of the participants in the Joint University Program (JUP) at Ohio University are briefly surveyed. During 1989 to 1990, five topics received emphasis. A spectrum-efficient weather data uplink system was designed, constructed, and flight tested. An integrated Global Positioning System/Inertial Navigation System (GPS/INS) study continued, utilizing the Redundant strapdown Inertial Measurement Unit (IMU) on loan from NASA. The Ridge Regression theory was refined and applied to air navigation scenarios. System Identification theory was applied to GPS data to point the way to better understanding of the effects of Selective Availability on civilian users of this navigation system. An analysis of thought-related (electroencephalographic) signals for application to control of computer systems that could have significance in aiding paraplegics or for hands-off systems control in industrial or air traffic control areas was carried out.

  4. 33 CFR 149.323 - What are the requirements for first aid kits?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... first aid kits? 149.323 Section 149.323 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Lifesaving Equipment Manned Deepwater Port Requirements § 149.323 What are the requirements for first aid kits? (a) Each manned deepwater port must have an industrial first aid kit, approved by an...

  5. Space Shuttle Navigation in the GPS Era

    NASA Technical Reports Server (NTRS)

    Goodman, John L.

    2001-01-01

    The Space Shuttle navigation architecture was originally designed in the 1970s. A variety of on-board and ground based navigation sensors and computers are used during the ascent, orbit coast, rendezvous, (including proximity operations and docking) and entry flight phases. With the advent of GPS navigation and tightly coupled GPS/INS Units employing strapdown sensors, opportunities to improve and streamline the Shuttle navigation process are being pursued. These improvements can potentially result in increased safety, reliability, and cost savings in maintenance through the replacement of older technologies and elimination of ground support systems (such as Tactical Air Control and Navigation (TACAN), Microwave Landing System (MLS) and ground radar). Selection and missionization of "off the shelf" GPS and GPS/INS units pose a unique challenge since the units in question were not originally designed for the Space Shuttle application. Various options for integrating GPS and GPS/INS units with the existing orbiter avionics system were considered in light of budget constraints, software quality concerns, and schedule limitations. An overview of Shuttle navigation methodology from 1981 to the present is given, along with how GPS and GPS/INS technology will change, or not change, the way Space Shuttle navigation is performed in the 21 5 century.

  6. Celestial Navigation in the USA, Fiji, and Tunisia

    NASA Astrophysics Data System (ADS)

    Holbrook, Jarita C.

    2015-05-01

    Today there are many coastal communities that are home to navigators who use stars for position finding at night; I was, however, unaware of this fact when I began researching celestial navigation practices in 1997. My project focused on three communities: the Moce Islanders of Fiji, the Kerkennah Islanders in Tunisia, and the U.S. Navy officers and students at the United States Naval Academy, Annapolis, Maryland. My goal was to answer the question of why people continue to navigate by the stars, but also to understand the role of technology in their navigation practices. Using anthropology techniques of ethnography including participant observation, formal and informal interviews, audio and videotaping, I gathered data over five years at the three communities. I began by learning the details of how they use the stars for navigation. Next, I learned about who did the navigation and where they learned to navigate. I gathered opinions on various navigation aids and instruments, and opinions about the future of using the stars for navigation. I listened to the stories that they told about navigating. In the United States I worked in English, in Fiji, in Fijian and English, and in Tunisia, French and English. For the formal interviews I worked with translators. The navigators use stars for navigating today but the future of their techniques is not certain. Though practiced today, these celestial navigation traditions have undergone and continue to undergo changes. New navigational technologies are part of the stimulation for change, thus 'a meeting of different worlds' is symbolized by peoples encounters with these technologies.

  7. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Proving Ground Center, Air Research and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Choctawhatchee Bay, aerial gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base, Fla... gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base,...

  8. Maps and navigation methods

    NASA Technical Reports Server (NTRS)

    Duval, A

    1922-01-01

    Different maps and scales are discussed with particular emphasis on their use in aviation. The author makes the observation that current navigation methods are slow and dangerous and should be replaced by scientific methods of navigation based on loxodromy and the use of the compass.

  9. Navigator program risk management

    NASA Technical Reports Server (NTRS)

    Wessen, Randii R.; Padilla, Deborah A.

    2004-01-01

    In this paper, program risk management as applied to the Navigator Program: In Search of New Worlds will be discussed. The Navigator Program's goals are to learn how planetary systems form and to search for those worlds that could or do harbor life.

  10. AIDS (image)

    MedlinePlus

    AIDS (acquired immune deficiency syndrome) is caused by HIV (human immunodeficiency virus), and is a syndrome that ... life-threatening illnesses. There is no cure for AIDS, but treatment with antiviral medicine can suppress symptoms. ...

  11. Hearing Aids

    MedlinePlus

    ... more in both quiet and noisy situations. Hearing aids help people who have hearing loss from damage ... your doctor. There are different kinds of hearing aids. They differ by size, their placement on or ...

  12. Improved artificial bee colony algorithm based gravity matching navigation method.

    PubMed

    Gao, Wei; Zhao, Bo; Zhou, Guang Tao; Wang, Qiu Ying; Yu, Chun Yang

    2014-07-18

    Gravity matching navigation algorithm is one of the key technologies for gravity aided inertial navigation systems. With the development of intelligent algorithms, the powerful search ability of the Artificial Bee Colony (ABC) algorithm makes it possible to be applied to the gravity matching navigation field. However, existing search mechanisms of basic ABC algorithms cannot meet the need for high accuracy in gravity aided navigation. Firstly, proper modifications are proposed to improve the performance of the basic ABC algorithm. Secondly, a new search mechanism is presented in this paper which is based on an improved ABC algorithm using external speed information. At last, modified Hausdorff distance is introduced to screen the possible matching results. Both simulations and ocean experiments verify the feasibility of the method, and results show that the matching rate of the method is high enough to obtain a precise matching position.

  13. Guidance, Navigation, and Control Program

    NASA Technical Reports Server (NTRS)

    Hinkel, Heather; Tamblyn, Scott; Jackson, William L.; Foster, Chris; Brazzel, Jack; Manning, Thomas R.; Clark, Fred; Spehar, Pete; Barrett, Jim D.; Milenkovic, Zoran

    2011-01-01

    The Rendezvous and Proximity Operations Program (RPOP) is real-time guidance, navigation, and control (GN&C) domain piloting-aid software that provides 3D Orbiter graphics and runs on the Space Shuttle's Criticality-3 Payload and General Support Computer (PGSC) in the crew cockpit. This software provides the crew with Situational Awareness during the rendezvous and proximity operations phases of flight. RPOP can be configured from flight to flight, accounting for mission-specific flight scenarios and target vehicles, via initialization load (I-load) data files. The software provides real-time, automated, closed-loop guidance recommendations and the capability to integrate the crew s manual backup techniques. The software can bring all relative navigation sensor data, including the Orbiter's GPC (general purpose computer) data, into one central application to provide comprehensive situational awareness of the rendezvous and proximity operations trajectory. RPOP also can separately maintain trajectory estimates (past, current, and predicted) based on certain data types and co-plot them, in order to show how the various navigation solutions compare. RPOP s best estimate of the relative trajectory is determined by a relative Kalman filter processing data provided by the sensor suite s most accurate sensor, the trajectory control sensor (TCS). Integrated with the Kalman filter is an algorithm that identifies the reflector that the TCS is tracking. Because RPOP runs on PC laptop computers, the development and certification lifecycles are more agile, flexible, and cheaper than those that govern the Orbiter FSW (flight software) that runs in the GPC. New releases of RPOP can be turned around on a 3- to 6-month template, from new Change Request (CR) to certification, depending on the complexity of the changes.

  14. Hearing Aids

    MedlinePlus

    ... type and degree of loss. Are there different styles of hearing aids? Styles of hearing aids Source: NIH/NIDCD Behind-the- ... the ear canal and are available in two styles. The in-the-canal (ITC) hearing aid is ...

  15. Navigation lights color study

    NASA Astrophysics Data System (ADS)

    Barbosa, Jose G.; Alberg, Matthew T.

    2015-05-01

    The chromaticity of navigation lights are defined by areas on the International Commission on Illumination (CIE) 1931 chromaticity diagram. The corner coordinates for these areas are specified in the International Regulations for Prevention of Collisions at Sea, 1972 (72 COLREGS). The navigation light's color of white, red, green, and yellow are bounded by these areas. The chromaticity values specified by the COLREGS for navigation lights were intended for the human visual system (HVS). The HVS can determine the colors of these lights easily under various conditions. For digital color camera imaging systems the colors of these lights are dependent on the camera's color spectral sensitivity, settings, and color correction. At night the color of these lights are used to quickly determine the relative course of vessels. If these lights are incorrectly identified or there is a delay in identifying them this could be a potential safety of ship concern. Vessels that use camera imaging systems exclusively for sight, at night, need to detect, identify, and discriminate navigation lights for navigation and collision avoidance. The introduction of light emitting diode (LED) lights and lights with different spectral signatures have the potential to be imaged very differently with an RGB color filter array (CFA) color camera than with the human eye. It has been found that some green navigation lights' images appear blue verse green. This has an impact on vessels that use camera imaging systems exclusively for navigation. This paper will characterize color cameras ability to properly reproducing navigation lights' color and survey a set of navigation light to determine if they conform to the COLREGS.

  16. Navigation Systems for Ablation

    PubMed Central

    Wood, B. J.; Kruecker, J.; Abi-Jaoudeh, N; Locklin, J.; Levy, E.; Xu, S.; Solbiati, L.; Kapoor, A.; Amalou, H.; Venkatesan, A.

    2010-01-01

    Navigation systems, devices and intra-procedural software are changing the way we practice interventional oncology. Prior to the development of precision navigation tools integrated with imaging systems, thermal ablation of hard-to-image lesions was highly dependent upon operator experience, spatial skills, and estimation of positron emission tomography-avid or arterial-phase targets. Numerous navigation systems for ablation bring the opportunity for standardization and accuracy that extends our ability to use imaging feedback during procedures. Existing systems and techniques are reviewed, and specific clinical applications for ablation are discussed to better define how these novel technologies address specific clinical needs, and fit into clinical practice. PMID:20656236

  17. Evaluation of navigation interfaces in virtual environments

    NASA Astrophysics Data System (ADS)

    Mestre, Daniel R.

    2014-02-01

    When users are immersed in cave-like virtual reality systems, navigational interfaces have to be used when the size of the virtual environment becomes larger than the physical extent of the cave floor. However, using navigation interfaces, physically static users experience self-motion (visually-induced vection). As a consequence, sensorial incoherence between vision (indicating self-motion) and other proprioceptive inputs (indicating immobility) can make them feel dizzy and disoriented. We tested, in two experimental studies, different locomotion interfaces. The objective was twofold: testing spatial learning and cybersickness. In a first experiment, using first-person navigation with a flystick ®, we tested the effect of sensorial aids, a spatialized sound or guiding arrows on the ground, attracting the user toward the goal of the navigation task. Results revealed that sensorial aids tended to impact negatively spatial learning. Moreover, subjects reported significant levels of cybersickness. In a second experiment, we tested whether such negative effects could be due to poorly controlled rotational motion during simulated self-motion. Subjects used a gamepad, in which rotational and translational displacements were independently controlled by two joysticks. Furthermore, we tested first- versus third-person navigation. No significant difference was observed between these two conditions. Overall, cybersickness tended to be lower, as compared to experiment 1, but the difference was not significant. Future research should evaluate further the hypothesis of the role of passively perceived optical flow in cybersickness, but manipulating the virtual environment'sperrot structure. It also seems that video-gaming experience might be involved in the user's sensitivity to cybersickness.

  18. Spatial cognition and navigation

    NASA Technical Reports Server (NTRS)

    Aretz, Anthony J.

    1989-01-01

    An experiment that provides data for the development of a cognitive model of pilot flight navigation is described. The experiment characterizes navigational awareness as the mental alignment of two frames of reference: (1) the ego centered reference frame that is established by the forward view out of the cockpit and (2) the world centered reference frame that is established by the aircraft's location on a map. The data support a model involving at least two components: (1) the perceptual encoding of the navigational landmarks and (2) the mental rotation of the map's world reference frame into alignment with the ego centered reference frame. The quantitative relationships of these two factors are provided as possible inputs for a computational model of spatial cognition during flight navigation.

  19. Soft tissue navigation for laparoscopic prostatectomy: evaluation of camera pose estimation for enhanced visualization

    NASA Astrophysics Data System (ADS)

    Baumhauer, M.; Simpfendörfer, T.; Schwarz, R.; Seitel, M.; Müller-Stich, B. P.; Gutt, C. N.; Rassweiler, J.; Meinzer, H.-P.; Wolf, I.

    2007-03-01

    We introduce a novel navigation system to support minimally invasive prostate surgery. The system utilizes transrectal ultrasonography (TRUS) and needle-shaped navigation aids to visualize hidden structures via Augmented Reality. During the intervention, the navigation aids are segmented once from a 3D TRUS dataset and subsequently tracked by the endoscope camera. Camera Pose Estimation methods directly determine position and orientation of the camera in relation to the navigation aids. Accordingly, our system does not require any external tracking device for registration of endoscope camera and ultrasonography probe. In addition to a preoperative planning step in which the navigation targets are defined, the procedure consists of two main steps which are carried out during the intervention: First, the preoperatively prepared planning data is registered with an intraoperatively acquired 3D TRUS dataset and the segmented navigation aids. Second, the navigation aids are continuously tracked by the endoscope camera. The camera's pose can thereby be derived and relevant medical structures can be superimposed on the video image. This paper focuses on the latter step. We have implemented several promising real-time algorithms and incorporated them into the Open Source Toolkit MITK (www.mitk.org). Furthermore, we have evaluated them for minimally invasive surgery (MIS) navigation scenarios. For this purpose, a virtual evaluation environment has been developed, which allows for the simulation of navigation targets and navigation aids, including their measurement errors. Besides evaluating the accuracy of the computed pose, we have analyzed the impact of an inaccurate pose and the resulting displacement of navigation targets in Augmented Reality.

  20. Onboard Navigation Systems Characteristics

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The space shuttle onboard navigation systems characteristics are described. A standard source of equations and numerical data for use in error analyses and mission simulations related to space shuttle development is reported. The sensor characteristics described are used for shuttle onboard navigation performance assessment. The use of complete models in the studies depend on the analyses to be performed, the capabilities of the computer programs, and the availability of computer resources.

  1. Airborne gravimetry, altimetry, and GPS navigation errors

    NASA Technical Reports Server (NTRS)

    Colombo, Oscar L.

    1992-01-01

    Proper interpretation of airborne gravimetry and altimetry requires good knowledge of aircraft trajectory. Recent advances in precise navigation with differential GPS have made it possible to measure gravity from the air with accuracies of a few milligals, and to obtain altimeter profiles of terrain or sea surface correct to one decimeter. These developments are opening otherwise inaccessible regions to detailed geophysical mapping. Navigation with GPS presents some problems that grow worse with increasing distance from a fixed receiver: the effect of errors in tropospheric refraction correction, GPS ephemerides, and the coordinates of the fixed receivers. Ionospheric refraction and orbit error complicate ambiguity resolution. Optimal navigation should treat all error sources as unknowns, together with the instantaneous vehicle position. To do so, fast and reliable numerical techniques are needed: efficient and stable Kalman filter-smoother algorithms, together with data compression and, sometimes, the use of simplified dynamics.

  2. Bibliography of Training Aids. 2nd Edition.

    ERIC Educational Resources Information Center

    Air Conditioning and Refrigeration Inst., Arlington, VA.

    A revision of ED 018 650, this annotated bibliography prepared by the Air-Conditioning and Refrigeration Institute lists training materials, films, and ancillary visual aids available from 34 member companies for use in air-conditioning and refrigeration training programs. Over 160 visual training aids are listed, arranged under the following…

  3. Voyager navigation strategy and accuracy

    NASA Technical Reports Server (NTRS)

    Jones, J. B.; Mcdanell, J. P.; Bantell, M. H., Jr.; Chadwick, C.; Jacobson, R. A.; Miller, L. J.; Synnott, S. P.; Van Allen, R. E.

    1977-01-01

    The paper presents the results of the prelaunch navigation studies conducted for the Mariner spacecraft launched toward encounters with the giant planets. The navigation system and the strategy for using this system are described. The requirements on the navigation system demanded by the goals of the project are mentioned, and the predicted navigational capability relative to each of the requirements is discussed. Baseline navigation results for three possible trajectories are analyzed.

  4. Financial Aid.

    ERIC Educational Resources Information Center

    Graves, Mary A.

    This workbook assists college and vocational school bound American Indian students in determining their financial needs and in locating sources of financial aid. A checklist helps students assess the state of their knowledge of financial programs; a glossary defines terms pertinent to the realm of financial aid (i.e., graduate study programs,…

  5. Teaching AIDS.

    ERIC Educational Resources Information Center

    Tonks, Douglas

    This book presents a curriculum to educate students about the risk of AIDS and HIV infection. The opening chapters of the book presents a discussion of: how teachers can create an environment of support for an AIDS education program; the political and educational implications of winning principal, district, and parental support for an AIDS…

  6. Aerocapture navigation at Neptune

    NASA Technical Reports Server (NTRS)

    Haw, Robert J.

    2003-01-01

    A proposed Neptune orbiter Aerocapture mission will use solar electric propulsion to send an orbiter to Neptune. Navigation feasibility of direct-entry aerocapture for orbit insertion at Neptune is shown. The navigation strategy baselines optical imaging and (delta)VLBI measurement in order to satisfy the flight system's atmosphere entry flight path angle, which is targeted to enter Neptune with an entry flight path angle of -11.6 . Error bars on the entry flight path angle of plus/minus0.55 (3(sigma)) are proposed. This requirement can be satisfied with a data cutoff 3.2 days prior to arrival. There is some margin in the arrival template to tighten (i.e. reduce) the entry corridor either by scheduling a data cutoff closer to Neptune or alternatively, reducing uncertainties by increasing the fidelity of the optical navigation camera.

  7. An approximate model for pulsar navigation simulation

    NASA Astrophysics Data System (ADS)

    Jovanovic, Ilija; Enright, John

    2016-02-01

    This paper presents an approximate model for the simulation of pulsar aided navigation systems. High fidelity simulations of these systems are computationally intensive and impractical for simulating periods of a day or more. Simulation of yearlong missions is done by abstracting navigation errors as periodic Gaussian noise injections. This paper presents an intermediary approximate model to simulate position errors for periods of several weeks, useful for building more accurate Gaussian error models. This is done by abstracting photon detection and binning, replacing it with a simple deterministic process. The approximate model enables faster computation of error injection models, allowing the error model to be inexpensively updated throughout a simulation. Testing of the approximate model revealed an optimistic performance prediction for non-millisecond pulsars with more accurate predictions for pulsars in the millisecond spectrum. This performance gap was attributed to noise which is not present in the approximate model but can be predicted and added to improve accuracy.

  8. Electromagnetically navigated laparoscopic ultrasound.

    PubMed

    Wilheim, Dirk; Feussner, Hubertus; Schneider, Armin; Harms, Jens

    2003-01-01

    A three-dimensional (3D) representation of laparoscopic ultrasound examinations could be helpful in diagnostic and therapeutic laparoscopy, but has not yet been realised with flexible laparoscopic ultrasound probes. Therefore, an electromagnetic navigation system was integrated into the tip of a conventional laparoscopic ultrasound probe. Navigated 3D laparoscopic ultrasound was compared with the imaging data of 3D navigated transcutaneous ultrasound and 3D computed tomography (CT) scan. The 3D CT scan served as the "gold standard". Clinical applicability in standardized operating room (OR) settings, imaging quality, diagnostic potential, and accuracy in volumetric assessment of various well-defined hepatic lesions were analyzed. Navigated 3D laparoscopic ultrasound facilitates exact definition of tumor location and margins. As compared with the "gold standard" of the 3D CT scans, 3D laparoscopic ultrasound has a tendency to underestimate the volume of the region of interest (ROI) (Delta3.1%). A comparison of 3D laparoscopy and transcutaneous 3D ultrasonography demonstrated clearly that the former is more accurate for volumetric assessment of the ROI and facilitates a more detailed display of the lesions. 3D laparoscopic ultrasound imaging with a navigated probe is technically feasible. The technique facilitates detailed ultrasound evaluation of laparoscopic procedures that involve visual, in-depth, and volumetric perception of complex liver pathologies. Navigated 3D laparoscopic ultrasound may have the potential to promote the practical role of laparoscopic ultrasonography, and become a valuable tool for local ablative therapy. In this article, our clinical experiences with a certified prototype of a 3D laparoscopic ultrasound probe, as well as its in vitro and in vivo evaluation, is reported.

  9. Mariner 9 navigation

    NASA Technical Reports Server (NTRS)

    Neil, W. J.; Jordan, J. F.; Zielenbach, J. W.; Wong, S. K.; Mitchell, R. T.; Webb, W. A.; Koskela, P. E.

    1973-01-01

    A final, comprehensive description of the navigation of Mariner 9-the first U.S. spacecraft to orbit another planet is provided. The Mariner 9 navigation function included not only precision flight path control but also pointing of the spacecraft's scientific instruments mounted on a two degree of freedom scan platform. To the extent appropriate, each section describes the perflight analyses on which the operational strategies and performance predictions were based. Inflight results are then discussed and compared with the preflight predictions. Postflight analyses, which were primarily concerned with developing a thorough understanding of unexpected in-flight results, are also presented.

  10. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S. Air... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.490 Atlantic Ocean...

  11. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S. Air... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.490 Atlantic Ocean...

  12. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S. Air... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.490 Atlantic Ocean...

  13. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S. Air... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.490 Atlantic Ocean...

  14. 33 CFR 334.1300 - Blying Sound area, Gulf of Alaska, Alaska; air-to-air gunnery practice area, Alaskan Air Command...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Blying Sound area, Gulf of Alaska, Alaska; air-to-air gunnery practice area, Alaskan Air Command, U.S. Air Force. 334.1300 Section 334.1300... AND RESTRICTED AREA REGULATIONS § 334.1300 Blying Sound area, Gulf of Alaska, Alaska;...

  15. 33 CFR 334.1300 - Blying Sound area, Gulf of Alaska, Alaska; air-to-air gunnery practice area, Alaskan Air Command...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Blying Sound area, Gulf of Alaska, Alaska; air-to-air gunnery practice area, Alaskan Air Command, U.S. Air Force. 334.1300 Section 334.1300... AND RESTRICTED AREA REGULATIONS § 334.1300 Blying Sound area, Gulf of Alaska, Alaska;...

  16. Mobile robot navigation using qualitative reasoning

    SciTech Connect

    Pin, F.G.; Watanabe, Yutaka.

    1993-01-01

    Vehicle control in a priori unknown, unpredictable, and dynamic environments requires many calculational and reasoning schemes to operate on the basis of very imprecise. incomplete, or unreliable data. Forsuch systems, in which all the uncertainties can not be engineered away, approximate reasoning may provide an alternative to the complexity and computational requirements of conventional uncertainty analysis and propagation techniques. Two types of computer boards including custom-designed VLSI chips have been developed to add a fuzzy inferencing capability to real-time control systems. The use of these boards and anapproach using superposition of elemental sensor-based behaviors for the development of qualitative reasoning schemes emulating human-like navigation are first discussed. We then describe how the human-like navigation schemes were implemented on a test-bed platform to investigate two control modes for driving a car in a priori unknown environments on the basis of sparse and imprecise sensor data. In the first mode, the car navigates fully autonomously, while in the second mode, the system acts as a driver's aid providing the driver with linguistic (fuzzy) commands to turn left or right and speed up or slow down depending on the obstacles perceived by the sensors. Experiments with both nodes of control are described in which the system uses only three acoustic range (sonar) sensor channels to perceive the environment. Simulationresults as well as indoors and outdoors experiments are presented and discussed to illustrate the feasibility and robustness of autonomous navigation and/or safety enhancing driver's aid using the new fuzzy inferencing hardware system and methodologies.

  17. Mobile robot navigation using qualitative reasoning

    SciTech Connect

    Pin, F.G.; Watanabe, Yutaka

    1993-03-01

    Vehicle control in a priori unknown, unpredictable, and dynamic environments requires many calculational and reasoning schemes to operate on the basis of very imprecise. incomplete, or unreliable data. Forsuch systems, in which all the uncertainties can not be engineered away, approximate reasoning may provide an alternative to the complexity and computational requirements of conventional uncertainty analysis and propagation techniques. Two types of computer boards including custom-designed VLSI chips have been developed to add a fuzzy inferencing capability to real-time control systems. The use of these boards and anapproach using superposition of elemental sensor-based behaviors for the development of qualitative reasoning schemes emulating human-like navigation are first discussed. We then describe how the human-like navigation schemes were implemented on a test-bed platform to investigate two control modes for driving a car in a priori unknown environments on the basis of sparse and imprecise sensor data. In the first mode, the car navigates fully autonomously, while in the second mode, the system acts as a driver`s aid providing the driver with linguistic (fuzzy) commands to turn left or right and speed up or slow down depending on the obstacles perceived by the sensors. Experiments with both nodes of control are described in which the system uses only three acoustic range (sonar) sensor channels to perceive the environment. Simulationresults as well as indoors and outdoors experiments are presented and discussed to illustrate the feasibility and robustness of autonomous navigation and/or safety enhancing driver`s aid using the new fuzzy inferencing hardware system and methodologies.

  18. Recent Events in Guidance, Navigation and Control

    NASA Technical Reports Server (NTRS)

    Polites, Michael E.; Bullman, Jack (Technical Monitor)

    2001-01-01

    This article summarizes recent events in Guidance, Navigation, and Control (GN&C) in space, weapons and missiles, and aircraft. The section on space includes recent developments with the following NASA spacecraft and space vehicles: Near Earth Asteroid Rendezvous, Deep Space 1, Microwave Anisotropy Probe, Earth Observer-1, Compton Gamma Ray Observatory, the International Space Station, X-38, and X-40A. The section on weapons and missiles includes recent developments with the following missiles: Joint Air-to-Surface Standoff Missile, Storm Shadow/Scalp EG precision standoff missile, Hellfire missile, AIM-120C Advanced medium-range air-to-air missile, Derby missile, Arrow 2, and the Standard Missile SM-3. The section on aircraft includes recent developments with the following aircraft: Joint Strike Fighter, X-31, V-22, Couger/SUDer Puma Mk. 2, Predator B 001, and the Unmanned Combat Air Vehicle.

  19. Navigation for everyday life

    SciTech Connect

    Fu, D.D.; Hammond, K.J.; Swain, M.J.

    1996-12-31

    Past work in navigation has worked toward the goal of producing an accurate map of the environment. While no one can deny the usefulness of such a map, the ideal of producing a complete map becomes unrealistic when an agent is faced with performing real tasks. And yet an agent accomplishing recurring tasks should navigate more efficiently as time goes by. We present a system which integrates navigation, planning, and vision. In this view, navigation supports the needs of a larger system as opposed to being a task in its own right. Whereas previous approaches assume an unknown and unstructured environment, we assume a structured environment whose organization is known, but whose specifics are unknown. The system is endowed with a wide range of visual capabilities as well as search plans for informed exploration of a simulated store constructed from real visual data. We demonstrate the agent finding items while mapping the world. In repeatedly retrieving items, the agent`s performance improves as the learned map becomes more useful.

  20. Navigating between the Dimensions

    ERIC Educational Resources Information Center

    Fleron, Julian F.; Ecke, Volker

    2011-01-01

    Generations have been inspired by Edwin A. Abbott's profound tour of the dimensions in his novella "Flatland: A Romance of Many Dimensions" (1884). This well-known satire is the story of a flat land inhabited by geometric shapes trying to navigate the subtleties of their geometric, social, and political positions. In this article, the authors…

  1. Learning for autonomous navigation

    NASA Technical Reports Server (NTRS)

    Angelova, Anelia; Howard, Andrew; Matthies, Larry; Tang, Benyang; Turmon, Michael; Mjolsness, Eric

    2005-01-01

    Autonomous off-road navigation of robotic ground vehicles has important applications on Earth and in space exploration. Progress in this domain has been retarded by the limited lookahead range of 3-D sensors and by the difficulty of preprogramming systems to understand the traversability of the wide variety of terrain they can encounter.

  2. Galileo asteroid encounter navigation

    NASA Technical Reports Server (NTRS)

    Murrow, D. W.; Chodas, P. W.; Kallemeyn, P. H.

    1990-01-01

    The Galileo spacecraft will be targeted to encounter one or more asteroids during its cruise to Jupiter. Accurate navigation will maximize science return from these asteroid flyby opportunities. Navigation errors for these encounters are dominated by uncertainties in the asteroid ephemeris, which is obtained from fits to ground-based observations. As the spacecraft approaches, on-board optical navigation dramatically improves knowledge of the spacecraft-relative asteroid position normal to the line of sight, while correlations in the asteroid ephemeris provide moderate improvement along the approach direction. The remaining uncertainty in encounter time can be further reduced only by improving the ground-based asteroid ephemeris. Uncertainties perpendicular to the line of sight can be reduced by improving the timing of optical navigation images and their placement with respect to the star background. At the closest approach to the asteroid Gaspra, the one-sigma errors in knowledge of the spacecraft position are less than 10 km in position and 25 seconds in encounter time.

  3. 4D Dynamic Required Navigation Performance Final Report

    NASA Technical Reports Server (NTRS)

    Finkelsztein, Daniel M.; Sturdy, James L.; Alaverdi, Omeed; Hochwarth, Joachim K.

    2011-01-01

    New advanced four dimensional trajectory (4DT) procedures under consideration for the Next Generation Air Transportation System (NextGen) require an aircraft to precisely navigate relative to a moving reference such as another aircraft. Examples are Self-Separation for enroute operations and Interval Management for in-trail and merging operations. The current construct of Required Navigation Performance (RNP), defined for fixed-reference-frame navigation, is not sufficiently specified to be applicable to defining performance levels of such air-to-air procedures. An extension of RNP to air-to-air navigation would enable these advanced procedures to be implemented with a specified level of performance. The objective of this research effort was to propose new 4D Dynamic RNP constructs that account for the dynamic spatial and temporal nature of Interval Management and Self-Separation, develop mathematical models of the Dynamic RNP constructs, "Required Self-Separation Performance" and "Required Interval Management Performance," and to analyze the performance characteristics of these air-to-air procedures using the newly developed models. This final report summarizes the activities led by Raytheon, in collaboration with GE Aviation and SAIC, and presents the results from this research effort to expand the RNP concept to a dynamic 4D frame of reference.

  4. Next Generation GPS Ground Control Segment (OCX) Navigation Design

    NASA Technical Reports Server (NTRS)

    Bertiger, Willy; Bar-Sever, Yoaz; Harvey, Nate; Miller, Kevin; Romans, Larry; Weiss, Jan; Doyle, Larry; Solorzano, Tara; Petzinger, John; Stell, Al

    2010-01-01

    In February 2010, a Raytheon-led team was selected by The Air Force to develop, implement, and operate the next generation GPS ground control segment (OCX). To meet and exceed the demanding OCX navigation performance requirements, the Raytheon team partnered with ITT (Navigation lead) and JPL to adapt major elements of JPL's navigation technology, proven in the operations of the Global Differential GPS (GDGPS) System. Key design goals for the navigation subsystem include accurate ephemeris and clock accuracy (user range error), ease of model upgrades, and a smooth and safe transition from the legacy system to OCX.We will describe key elements of the innovative architecture of the OCX navigation subsystem,and demonstrate the anticipated performance of the system through high fidelity simulations withactual GPS measurements.

  5. Nonlinear trajectory navigation

    NASA Astrophysics Data System (ADS)

    Park, Sang H.

    Trajectory navigation entails the solution of many different problems that arise due to uncertain knowledge of the spacecraft state, including orbit prediction, correction maneuver design, and trajectory estimation. In practice, these problems are usually solved based on an assumption that linear dynamical models sufficiently approximate the local trajectory dynamics and their associated statistics. However, astrodynamics problems are nonlinear in general and linear spacecraft dynamics models can fail to characterize the true trajectory dynamics when the system is subject to a highly unstable environment or when mapped over a long time period. This limits the performance of traditional navigation techniques and can make it difficult to perform precision analysis or robust navigation. This dissertation presents an alternate method for spacecraft trajectory navigation based on a nonlinear local trajectory model and their statistics in an analytic framework. For a given reference trajectory, we first solve for the higher order Taylor series terms that describe the localized nonlinear motion and develop an analytic expression for the relative solution flow. We then discuss the nonlinear dynamical mapping of a spacecraft's probability density function by solving the Fokker-Planck equation for a deterministic system. From this result we derive an analytic method for orbit uncertainty propagation which can replicate Monte-Carlo simulations with the benefit of added flexibility in initial orbit statistics. Using this approach, we introduce the concept of the statistically correct trajectory where we directly incorporate statistical information about an orbit state into the trajectory design process. As an extension of this concept, we define a nonlinear statistical targeting method where we solve for a correction maneuver which intercepts the desired target on average. Then we apply our results to a Bayesian filtering problem to obtain a general filtering algorithm for

  6. Hearing Aid

    MedlinePlus

    ... and Food and Drug Administration Staff FDA permits marketing of new laser-based hearing aid with potential ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  7. Development of simulation techniques suitable for the analysis of air traffic control situations and instrumentation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A terminal area simulation is described which permits analysis and synthesis of current and advanced air traffic management system configurations including ground and airborne instrumentation and new and modified aircraft characteristics. Ground elements in the simulation include navigation aids, surveillance radars, communication links, air-route structuring, ATC procedures, airport geometries and runway handling constraints. Airborne elements include traffic samples with individual aircraft performance and operating characteristics and aircraft navigation equipment. The simulation also contains algorithms for conflict detection, conflict resolution, sequencing and pilot-controller data links. The simulation model is used to determine the sensitivities of terminal area traffic flow, safety and congestion to aircraft performance characteristics, avionics systems, and other ATC elements.

  8. Investigation on navigation patterns of inertial/celestial integrated systems

    NASA Astrophysics Data System (ADS)

    Luo, Dacheng; Liu, Yan; Liu, Zhiguo; Jiao, Wei; Wang, Qiuyan

    2014-11-01

    It is known that Strapdown Inertial Navigation System (SINS), Global Navigation Satellite System (GNSS) and Celestial Navigation System (CNS) can complement each other's advantages. The SINS/CNS integrated system, which has the characteristics of strong autonomy, high accuracy and good anti-jamming, is widely used in military and civilian applications. Similar to SINS/GNSS integrated system, the SINS/CNS integrated system can also be divided into three kinds according to the difference of integrating depth, i.e., loosely coupled pattern, tightly coupled pattern and deeply coupled pattern. In this paper, the principle and characteristics of each pattern of SINS/CNS system are analyzed. Based on the comparison of these patterns, a novel deeply coupled SINS/CNS integrated navigation scheme is proposed. The innovation of this scheme is that a new star pattern matching method aided by SINS information is put forward. Thus the complementary features of these two subsystems are reflected.

  9. Designing Navigation Support in Hypertext Systems Based on Navigation Patterns

    ERIC Educational Resources Information Center

    Puntambekar, Sadhana; Stylianou, Agni

    2005-01-01

    In this paper, we present two studies designed to help students navigate effectively and learn from a hypertext system, CoMPASS. Our first study ("N" = 74) involved an analysis of students' navigation patterns to group them into clusters, using a "k"-means clustering technique. Based on this analysis, navigation patterns were grouped into four…

  10. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  11. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  12. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  13. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  14. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  15. 33 CFR 334.865 - Naval Air Station North Island, San Diego, California, restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Naval Air Station North Island, San Diego, California, restricted area. 334.865 Section 334.865 Navigation and Navigable Waters CORPS... REGULATIONS § 334.865 Naval Air Station North Island, San Diego, California, restricted area. (a) The...

  16. 33 CFR 334.865 - Naval Air Station North Island, San Diego, California, restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Naval Air Station North Island, San Diego, California, restricted area. 334.865 Section 334.865 Navigation and Navigable Waters CORPS... REGULATIONS § 334.865 Naval Air Station North Island, San Diego, California, restricted area. (a) The...

  17. Integrated INS/GPS Navigation from a Popular Perspective

    NASA Technical Reports Server (NTRS)

    Omerbashich, Mensur

    2002-01-01

    Inertial navigation, blended with other navigation aids, Global Positioning System (GPS) in particular, has gained significance due to enhanced navigation and inertial reference performance and dissimilarity for fault tolerance and anti-jamming. Relatively new concepts based upon using Differential GPS (DGPS) blended with Inertial (and visual) Navigation Sensors (INS) offer the possibility of low cost, autonomous aircraft landing. The FAA has decided to implement the system in a sophisticated form as a new standard navigation tool during this decade. There have been a number of new inertial sensor concepts in the recent past that emphasize increased accuracy of INS/GPS versus INS and reliability of navigation, as well as lower size and weight, and higher power, fault tolerance, and long life. The principles of GPS are not discussed; rather the attention is directed towards general concepts and comparative advantages. A short introduction to the problems faced in kinematics is presented. The intention is to relate the basic principles of kinematics to probably the most used navigation method in the future-INS/GPS. An example of the airborne INS is presented, with emphasis on how it works. The discussion of the error types and sources in navigation, and of the role of filters in optimal estimation of the errors then follows. The main question this paper is trying to answer is 'What are the benefits of the integration of INS and GPS and how is this, navigation concept of the future achieved in reality?' The main goal is to communicate the idea about what stands behind a modern navigation method.

  18. Navigation and attitude reference for autonomous satellite launch and orbital operations

    NASA Technical Reports Server (NTRS)

    Kau, S. P.

    1979-01-01

    The navigation and attitude reference performance of a strapdown system are investigated for applications to autonomous satellite launch and orbital operations. It is assumed that satellite payloads are integrated into existing missile systems and that the boost, orbit insertion, and in-orbit operation of the satellite are performed autonomously without relying on external support facilities. Autonomous and long term accurate navigation and attitude reference are provided by a strapdown inertial navigation system aided by a star sensor and earth landmark sensor. Sensor measurement geometry and navigation and attitude update mechanizations are discussed. Performance analysis data are presented for following functional elements: (1) prelaunch alignment; (2) boost navigation and attitude reference; (3) post boost stellar attitude and navigation updates; (4) orbital navigation update using sensor landmark measurements; and (5) in-orbit stellar attitude update and gyro calibration. The system performances are shown to satisfy the requirements of a large class of satellite payload applications.

  19. AIDS lymphomas.

    PubMed

    Middleton, G W; Lau, R K

    1992-01-01

    Chronically immunosuppressed individuals are susceptible to lymphoreticular tumors. Up to 15% of patients with congenital deficiencies such as ataxia=telangiectasia may develop malignancies, mainly high-grade B cell non=Hodgkin's lymphomas (NHLs). AIDS lymphomas are comprised of NHLs including Burkitt's lymphoma (BL) and primary cerebral lymphomas (PCLs). Almost 3% of all AIDS patients (2824 of 97,258 cases) developed NHL. Epstein-Barr virus (EBV) as a co-factor in AIDS lymphomagenesis has been studied: in 12 cases of 24 AIDS lymphomas EBV by DNA in situ hybridization was found. In an analysis of 6 primary cerebral lymphomas, .5 were positive for EBV DNA by Southern blotting. In Burkitt's lymphoma the characteristic genetic alteration affects the c-myc oncogene. In 1/3 of BL p53 mutations were found but none in the 43 NHLs suggesting that p53 mutations and c-myc activation act synergistically in the pathogenesis of these tumors. Cytotoxic agents dideoxyinosine, dideoxycytosine, and zidovudine may cause secondary neoplasia. 8 of 55 AIDS patients under zidovudine treatment developed high-grade lymphoma 23.8 months subsequently; recently doses were reduced. PCL was found in 21 of 90 patients. A 5.2 months survival was associated with combined treatment with cyclophosphamide, Oncovin (vincristine), methotrexate, etoposide, and cytosine arabinoside compared with 11.3 months with chemotherapy. Colony-stimulating factors (CSFs) alleviate drug-induced myelotoxicity and zidovudine-induced neutropenia, however, l8 of 11 patients receiving granulocyte-macrophage CSF developed hematological toxicity. Interleukine-2 produced by T-helper cells enhancing tumor cells cytotoxicity has been used in AIDS-associated cryptosporidial diarrhea and in 4 patients with AIDS lymphoma with modest response, but its stimulation of the HIV-infected substrate may increase viral proliferation.

  20. Terrain-Adaptive Navigation Architecture

    NASA Technical Reports Server (NTRS)

    Helmick, Daniel M.; Angelova, Anelia; Matthies, Larry H.; Helmick, Daniel M.

    2008-01-01

    A navigation system designed for a Mars rover has been designed to deal with rough terrain and/or potential slip when evaluating and executing paths. The system also can be used for any off-road, autonomous vehicles. The system enables vehicles to autonomously navigate different terrain challenges including dry river channel systems, putative shorelines, and gullies emanating from canyon walls. Several of the technologies within this innovation increase the navigation system s capabilities compared to earlier rover navigation algorithms.

  1. Coastal Piloting & Charting: Navigation 101.

    ERIC Educational Resources Information Center

    Osinski, Alison

    This curriculum guide for a beginning course on marine navigation describes marine navigation (the art of and science of determining position of a ship and its movement from one position to another in order to keep track of where the ship is and where it is going) and defines dead reckoning, piloting, electronic navigation, and celestial…

  2. Confronting AIDS.

    PubMed

    Squire, L

    1998-03-01

    By 2020, HIV/AIDS will be the leading infectious killer of young and middle-aged adults in the developing world. Past gains in life expectancy are already being eroded in some countries. Millions of lives can, however, be saved if developing country governments, the international community, and nongovernmental organizations act now. Although more than 11 million people have already died of AIDS, 2.3 billion people live in developing countries in which the disease has not yet spread beyond certain risk groups. If the spread of HIV is checked, the quality of care available to people who are infected with HIV will probably be better than it would be in the context of a full-blown AIDS epidemic. However, while governments need to respond urgently to HIV/AIDS, using resources to help people with AIDS will reduce the resources available for other investments, such as child education, providing safe drinking water, and building roads. Economics can help governments set priorities as they decide how best to allocate their available resources. Externalities, public goods, and redistribution are discussed. All countries will need to use some combination of preventive and coping measures. PMID:12293445

  3. Self-navigating robot

    NASA Technical Reports Server (NTRS)

    Thompson, A. M.

    1978-01-01

    Rangefinding equipment and onboard navigation system determine best route from point to point. Research robot has two TV cameras and laser for scanning and mapping its environment. Path planner finds most direct, unobstructed route that requires minimum expenditure of energy. Distance is used as measure of energy expense, although other measures such as time or power consumption (which would depend on the topography of the path) may be used.

  4. 33 CFR 2.36 - Navigable waters of the United States, navigable waters, and territorial waters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Navigable waters of the United States, navigable waters, and territorial waters. 2.36 Section 2.36 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL JURISDICTION Jurisdictional Terms § 2.36 Navigable waters of the United States, navigable...

  5. Multisensor robot navigation system

    NASA Astrophysics Data System (ADS)

    Persa, Stelian; Jonker, Pieter P.

    2002-02-01

    Almost all robot navigation systems work indoors. Outdoor robot navigation systems offer the potential for new application areas. The biggest single obstacle to building effective robot navigation systems is the lack of accurate wide-area sensors for trackers that report the locations and orientations of objects in an environment. Active (sensor-emitter) tracking technologies require powered-device installation, limiting their use to prepared areas that are relative free of natural or man-made interference sources. The hybrid tracker combines rate gyros and accelerometers with compass and tilt orientation sensor and DGPS system. Sensor distortions, delays and drift required compensation to achieve good results. The measurements from sensors are fused together to compensate for each other's limitations. Analysis and experimental results demonstrate the system effectiveness. The paper presents a field experiment for a low-cost strapdown-IMU (Inertial Measurement Unit)/DGPS combination, with data processing for the determination of 2-D components of position (trajectory), velocity and heading. In the present approach we have neglected earth rotation and gravity variations, because of the poor gyroscope sensitivities of our low-cost ISA (Inertial Sensor Assembly) and because of the relatively small area of the trajectory. The scope of this experiment was to test the feasibility of an integrated DGPS/IMU system of this type and to develop a field evaluation procedure for such a combination.

  6. Lunar Navigation Determination System - LaNDS

    NASA Technical Reports Server (NTRS)

    Quinn, David; Talabac, Stephen

    2012-01-01

    A portable comprehensive navigational system has been developed that both robotic and human explorers can use to determine their location, attitude, and heading anywhere on the lunar surface independent of external infrastructure (needs no Lunar satellite network, line of sight to the Sun or Earth, etc.). The system combines robust processing power with an extensive topographical database to create a real-time atlas (GIS Geospatial Information System) that is able to autonomously control and monitor both single unmanned rovers and fleets of rovers, as well as science payload stations. The system includes provisions for teleoperation and tele-presence. The system accepts (but does not require) inputs from a wide range of sensors. A means was needed to establish a location when the search is taken deep in a crater (looking for water ice) and out of view of Earth or any other references. A star camera can be employed to determine the user's attitude in menial space and stellar map in body space. A local nadir reference (e.g., an accelerometer that orients the nadir vector in body space) can be used in conjunction with a digital ephemeris and gravity model of the Moon to isolate the latitude, longitude, and azimuth of the user on the surface. That information can be used in conjunction with a Lunar GIS and advanced navigation planning algorithms to aid astronauts (or other assets) to navigate on the Lunar surface.

  7. Logical-Semantic Visual Navigators--Aids for Teachers

    ERIC Educational Resources Information Center

    Khuziakhmetov, Anvar N.; Steinberg, Valery E.

    2016-01-01

    The relevance of the article in question is that the success of pupils' learning depends not only on the aptitude of pupils, but also on the teaching technique, including universal educational technique of various complexities. This problem is relevant on all levels of learning--from nursery schools up to higher education, including refresher…

  8. 75 FR 8390 - St. Croix River Aids to Navigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... Federal Register (73 FR 3316). Information on Services for Individuals With Disabilities For information... meeting using any one of the following methods: (1) D8localnoticefeedback@uscg.mil . (2) Austin.T.Glass... Austin Glass, U.S. Coast Guard, Eighth District, Waterways Management, at Austin.T.Glass@uscg.mil...

  9. Air traffic management evaluation tool

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar (Inventor); Sheth, Kapil S. (Inventor); Chatterji, Gano Broto (Inventor); Bilimoria, Karl D. (Inventor); Grabbe, Shon (Inventor); Schipper, John F. (Inventor)

    2012-01-01

    Methods for evaluating and implementing air traffic management tools and approaches for managing and avoiding an air traffic incident before the incident occurs. A first system receives parameters for flight plan configurations (e.g., initial fuel carried, flight route, flight route segments followed, flight altitude for a given flight route segment, aircraft velocity for each flight route segment, flight route ascent rate, flight route descent route, flight departure site, flight departure time, flight arrival time, flight destination site and/or alternate flight destination site), flight plan schedule, expected weather along each flight route segment, aircraft specifics, airspace (altitude) bounds for each flight route segment, navigational aids available. The invention provides flight plan routing and direct routing or wind optimal routing, using great circle navigation and spherical Earth geometry. The invention provides for aircraft dynamics effects, such as wind effects at each altitude, altitude changes, airspeed changes and aircraft turns to provide predictions of aircraft trajectory (and, optionally, aircraft fuel use). A second system provides several aviation applications using the first system. Several classes of potential incidents are analyzed and averted, by appropriate change en route of one or more parameters in the flight plan configuration, as provided by a conflict detection and resolution module and/or traffic flow management modules. These applications include conflict detection and resolution, miles-in trail or minutes-in-trail aircraft separation, flight arrival management, flight re-routing, weather prediction and analysis and interpolation of weather variables based upon sparse measurements. The invention combines these features to provide an aircraft monitoring system and an aircraft user system that interact and negotiate changes with each other.

  10. Energy Navigation: Simulation Evaluation and Benefit Analysis

    NASA Technical Reports Server (NTRS)

    Williams, David H.; Oseguera-Lohr, Rosa M.; Lewis, Elliot T.

    2011-01-01

    This paper presents results from two simulation studies investigating the use of advanced flight-deck-based energy navigation (ENAV) and conventional transport-category vertical navigation (VNAV) for conducting a descent through a busy terminal area, using Continuous Descent Arrival (CDA) procedures. This research was part of the Low Noise Flight Procedures (LNFP) element within the Quiet Aircraft Technology (QAT) Project, and the subsequent Airspace Super Density Operations (ASDO) research focus area of the Airspace Project. A piloted simulation study addressed development of flight guidance, and supporting pilot and Air Traffic Control (ATC) procedures for high density terminal operations. The procedures and charts were designed to be easy to understand, and to make it easy for the crew to make changes via the Flight Management Computer Control-Display Unit (FMC-CDU) to accommodate changes from ATC.

  11. Integrated navigation method based on inertial navigation system and Lidar

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoyue; Shi, Haitao; Pan, Jianye; Zhang, Chunxi

    2016-04-01

    An integrated navigation method based on the inertial navigational system (INS) and Lidar was proposed for land navigation. Compared with the traditional integrated navigational method and dead reckoning (DR) method, the influence of the inertial measurement unit (IMU) scale factor and misalignment was considered in the new method. First, the influence of the IMU scale factor and misalignment on navigation accuracy was analyzed. Based on the analysis, the integrated system error model of INS and Lidar was established, in which the IMU scale factor and misalignment error states were included. Then the observability of IMU error states was analyzed. According to the results of the observability analysis, the integrated system was optimized. Finally, numerical simulation and a vehicle test were carried out to validate the availability and utility of the proposed INS/Lidar integrated navigational method. Compared with the test result of a traditional integrated navigation method and DR method, the proposed integrated navigational method could result in a higher navigation precision. Consequently, the IMU scale factor and misalignment error were effectively compensated by the proposed method and the new integrated navigational method is valid.

  12. Classroom Aids

    ERIC Educational Resources Information Center

    Science Activities: Classroom Projects and Curriculum Ideas, 2007

    2007-01-01

    This article describes 6 aids for science instruction, including (1) the use of fudge to represent lava; (2) the "Living by Chemistry" program, designed to make high school chemistry more accessible to a diverse pool of students without sacrificing content; (3) NOAA and NSTA's online coral reef teaching tool, a new web-based "science toolbox" for…

  13. Dietitian Aide.

    ERIC Educational Resources Information Center

    Texas Tech. Univ., Lubbock. School of Home Economics.

    This course of study for the dietitian aide is one of a series available for use by teacher-coordinators and students in Grade 11 and 12 home economics cooperative education programs. Based on job analysis interviews with health care facilities personnel, this course was prepared by teachers and Instructional Materials Center staff, field-tested,…

  14. Floriculture Aide.

    ERIC Educational Resources Information Center

    Martin, Joyce; Looney, Era

    Designed for use in a self-paced, open-entry/open-exit vocational training program for a floriculture aide, this program guide is one of six for teachers of adult women offenders from a correctional institution. Module topic outlines and sample lesson plans are presented on eleven topics: occupational opportunities in the retail florist industry;…

  15. 33 CFR 401.53 - Obstructing navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Obstructing navigation. 401.53 Section 401.53 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.53...

  16. 33 CFR 401.53 - Obstructing navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Obstructing navigation. 401.53 Section 401.53 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.53...

  17. 33 CFR 401.35 - Navigation underway.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Navigation underway. 401.35 Section 401.35 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.35...

  18. 33 CFR 401.35 - Navigation underway.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Navigation underway. 401.35 Section 401.35 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.35...

  19. 33 CFR 401.35 - Navigation underway.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Navigation underway. 401.35 Section 401.35 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.35...

  20. 33 CFR 401.35 - Navigation underway.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Navigation underway. 401.35 Section 401.35 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.35...

  1. 33 CFR 401.53 - Obstructing navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Obstructing navigation. 401.53 Section 401.53 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.53...

  2. 33 CFR 401.35 - Navigation underway.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Navigation underway. 401.35 Section 401.35 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.35...

  3. 33 CFR 401.53 - Obstructing navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Obstructing navigation. 401.53 Section 401.53 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.53...

  4. 33 CFR 401.53 - Obstructing navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Obstructing navigation. 401.53 Section 401.53 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.53...

  5. Control algorithms for autonomous robot navigation

    SciTech Connect

    Jorgensen, C.C.

    1985-09-20

    This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced.

  6. Performance Characteristic Mems-Based IMUs for UAVs Navigation

    NASA Astrophysics Data System (ADS)

    Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

    2015-08-01

    Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

  7. Tuberculosis Facts - TB and HIV/AIDS

    MedlinePlus

    Tuberculosis (TB) Facts TB and HIV/AIDS What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

  8. Aeronautic Instruments. Section VI : Aerial Navigation and Navigating Instruments

    NASA Technical Reports Server (NTRS)

    Eaton, H N

    1923-01-01

    This report outlines briefly the methods of aerial navigation which have been developed during the past few years, with a description of the different instruments used. Dead reckoning, the most universal method of aerial navigation, is first discussed. Then follows an outline of the principles of navigation by astronomical observation; a discussion of the practical use of natural horizons, such as sea, land, and cloud, in making extant observations; the use of artificial horizons, including the bubble, pendulum, and gyroscopic types. A description is given of the recent development of the radio direction finder and its application to navigation.

  9. Learning for Autonomous Navigation

    NASA Technical Reports Server (NTRS)

    Angelova, Anelia; Howard, Andrew; Matthies, Larry; Tang, Benyang; Turmon, Michael; Mjolsness, Eric

    2005-01-01

    Robotic ground vehicles for outdoor applications have achieved some remarkable successes, notably in autonomous highway following (Dickmanns, 1987), planetary exploration (1), and off-road navigation on Earth (1). Nevertheless, major challenges remain to enable reliable, high-speed, autonomous navigation in a wide variety of complex, off-road terrain. 3-D perception of terrain geometry with imaging range sensors is the mainstay of off-road driving systems. However, the stopping distance at high speed exceeds the effective lookahead distance of existing range sensors. Prospects for extending the range of 3-D sensors is strongly limited by sensor physics, eye safety of lasers, and related issues. Range sensor limitations also allow vehicles to enter large cul-de-sacs even at low speed, leading to long detours. Moreover, sensing only terrain geometry fails to reveal mechanical properties of terrain that are critical to assessing its traversability, such as potential for slippage, sinkage, and the degree of compliance of potential obstacles. Rovers in the Mars Exploration Rover (MER) mission have got stuck in sand dunes and experienced significant downhill slippage in the vicinity of large rock hazards. Earth-based off-road robots today have very limited ability to discriminate traversable vegetation from non-traversable vegetation or rough ground. It is impossible today to preprogram a system with knowledge of these properties for all types of terrain and weather conditions that might be encountered.

  10. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  11. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  12. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  13. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  14. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  15. Development of a GPS/INS/MAG navigation system and waypoint navigator for a VTOL UAV

    NASA Astrophysics Data System (ADS)

    Meister, Oliver; Mönikes, Ralf; Wendel, Jan; Frietsch, Natalie; Schlaile, Christian; Trommer, Gert F.

    2007-04-01

    Unmanned aerial vehicles (UAV) can be used for versatile surveillance and reconnaissance missions. If a UAV is capable of flying automatically on a predefined path the range of possible applications is widened significantly. This paper addresses the development of the integrated GPS/INS/MAG navigation system and a waypoint navigator for a small vertical take-off and landing (VTOL) unmanned four-rotor helicopter with a take-off weight below 1 kg. The core of the navigation system consists of low cost inertial sensors which are continuously aided with GPS, magnetometer compass, and a barometric height information. Due to the fact, that the yaw angle becomes unobservable during hovering flight, the integration with a magnetic compass is mandatory. This integration must be robust with respect to errors caused by the terrestrial magnetic field deviation and interferences from surrounding electronic devices as well as ferrite metals. The described integration concept with a Kalman filter overcomes the problem that erroneous magnetic measurements yield to an attitude error in the roll and pitch axis. The algorithm provides long-term stable navigation information even during GPS outages which is mandatory for the flight control of the UAV. In the second part of the paper the guidance algorithms are discussed in detail. These algorithms allow the UAV to operate in a semi-autonomous mode position hold as well an complete autonomous waypoint mode. In the position hold mode the helicopter maintains its position regardless of wind disturbances which ease the pilot job during hold-and-stare missions. The autonomous waypoint navigator enable the flight outside the range of vision and beyond the range of the radio link. Flight test results of the implemented modes of operation are shown.

  16. 33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION...

  17. 33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION...

  18. 33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION...

  19. 33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION...

  20. 33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION...

  1. The range scheduling aid

    NASA Technical Reports Server (NTRS)

    Halbfinger, Eliezer M.; Smith, Barry D.

    1991-01-01

    The Air Force Space Command schedules telemetry, tracking and control activities across the Air Force Satellite Control network. The Range Scheduling Aid (RSA) is a rapid prototype combining a user-friendly, portable, graphical interface with a sophisticated object-oriented database. The RSA has been a rapid prototyping effort whose purpose is to elucidate and define suitable technology for enhancing the performance of the range schedulers. Designing a system to assist schedulers in their task and using their current techniques as well as enhancements enabled by an electronic environment, has created a continuously developing model that will serve as a standard for future range scheduling systems. The RSA system is easy to use, easily ported between platforms, fast, and provides a set of tools for the scheduler that substantially increases his productivity.

  2. SOUTH SIDE OF TANKS. LOADING DOCK, WITH FIRST AID STATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SOUTH SIDE OF TANKS. LOADING DOCK, WITH FIRST AID STATION IN LEFT FOREGROUND - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Liquid Oxygen & Nitrogen Storage Tank Farm, Intersection of Altair & Jupiter Boulevards, Boron, Kern County, CA

  3. Augmented Reality as a Navigation Tool to Employment Opportunities for Postsecondary Education Students with Intellectual Disabilities and Autism

    ERIC Educational Resources Information Center

    McMahon, Don; Cihak, David F.; Wright, Rachel

    2015-01-01

    The purpose of this study was to examine the effects of location-based augmented reality navigation compared to Google Maps and paper maps as navigation aids for students with disabilities. The participants in this single subject study were three college students with intellectual disability and one college student with autism spectrum disorder.…

  4. HIV/AIDS Basics

    MedlinePlus

    ... Enter ZIP code or city Follow Act Against AIDS Act Against AIDS @talkHIV Act Against AIDS Get Email Updates on AAA Anonymous Feedback HIV/AIDS Media Infographics Syndicated Content Podcasts Slide Sets HIV/ ...

  5. 14 CFR 121.305 - Flight and navigational equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS OPERATING... following flight and navigational instruments and equipment: (a) An airspeed indicating system with heated... is required when a third attitude instrument system usable through flight attitudes of 360° of...

  6. 241. BUILDINGS 455, 456, 509, 510 AND 457 (CELESTIAL NAVIGATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    241. BUILDINGS 455, 456, 509, 510 AND 457 (CELESTIAL NAVIGATION COMPLEX), 1942-43. BUREAU OF YARDS AND DOCKS STANDARD PLANS. VIEW NORTH ACROSS WASP ST. SHOWING THE 4 TRAINING SILOS FROM LEFT TO RIGHT: BUILDINGS 455, 456, 509, AND 510; AND, BESIDE THEM, BUILDING 457. - Quonset Point Naval Air Station, Roger Williams Way, North Kingstown, Washington County, RI

  7. Comprehension of Navigation Directions

    NASA Technical Reports Server (NTRS)

    Healy, Alice F.; Schneider, Vivian I.

    2002-01-01

    Subjects were shown navigation instructions varying in length directing them to move in a space represented by grids on a computer screen. They followed the instructions by clicking on the grids in the locations specified. Some subjects repeated back the instructions before following them, some did not, and others repeated back the instructions in reduced form, including only the critical words. The commands in each message were presented simultaneously for half of the subjects and sequentially for the others. For the longest messages, performance was better on the initial commands and worse on the final commands with simultaneous than with sequential presentation. Instruction repetition depressed performance, but reduced repetition removed this disadvantage. Effects of presentation format were attributed to visual scanning strategies. The advantage for reduced repetition was attributable either to enhanced visual scanning or to reduced output interference. A follow-up study with auditory presentation supported the visual scanning explanation.

  8. Stardust Navigation Covariance Analysis

    NASA Technical Reports Server (NTRS)

    Menon, Premkumar R.

    2000-01-01

    The Stardust spacecraft was launched on February 7, 1999 aboard a Boeing Delta-II rocket. Mission participants include the National Aeronautics and Space Administration (NASA), the Jet Propulsion Laboratory (JPL), Lockheed Martin Astronautics (LMA) and the University of Washington. The primary objective of the mission is to collect in-situ samples of the coma of comet Wild-2 and return those samples to the Earth for analysis. Mission design and operational navigation for Stardust is performed by the Jet Propulsion Laboratory (JPL). This paper will describe the extensive JPL effort in support of the Stardust pre-launch analysis of the orbit determination component of the mission covariance study. A description of the mission and it's trajectory will be provided first, followed by a discussion of the covariance procedure and models. Predicted accuracy's will be examined as they relate to navigation delivery requirements for specific critical events during the mission. Stardust was launched into a heliocentric trajectory in early 1999. It will perform an Earth Gravity Assist (EGA) on January 15, 2001 to acquire an orbit for the eventual rendezvous with comet Wild-2. The spacecraft will fly through the coma (atmosphere) on the dayside of Wild-2 on January 2, 2004. At that time samples will be obtained using an aerogel collector. After the comet encounter Stardust will return to Earth when the Sample Return Capsule (SRC) will separate and land at the Utah Test Site (UTTR) on January 15, 2006. The spacecraft will however be deflected off into a heliocentric orbit. The mission is divided into three phases for the covariance analysis. They are 1) Launch to EGA, 2) EGA to Wild-2 encounter and 3) Wild-2 encounter to Earth reentry. Orbit determination assumptions for each phase are provided. These include estimated and consider parameters and their associated a-priori uncertainties. Major perturbations to the trajectory include 19 deterministic and statistical maneuvers

  9. Navigation in endoscopic soft tissue surgery: perspectives and limitations.

    PubMed

    Baumhauer, Matthias; Feuerstein, Marco; Meinzer, Hans-Peter; Rassweiler, J

    2008-04-01

    Despite rapid developments in the research areas of medical imaging, medical image processing, and robotics, the use of computer assistance in surgical routine is still limited to diagnostics, surgical planning, and interventions on mostly rigid structures. In order to establish a computer-aided workflow from diagnosis to surgical treatment and follow-up, several proposals for computer-assisted soft tissue interventions have been made in recent years. By means of different pre- and intraoperative information sources, such as surgical planning, intraoperative imaging, and tracking devices, surgical navigation systems aim to support surgeons in localizing anatomical targets, observing critical structures, and sparing healthy tissue. Current research in particular addresses the problem of organ shift and tissue deformation, and obstacles in communication between navigation system and surgeon. In this paper, we review computer-assisted navigation systems for soft tissue surgery. We concentrate on approaches that can be applied in endoscopic thoracic and abdominal surgery, because endoscopic surgery has special needs for image guidance due to limitations in perception. Furthermore, this paper informs the reader about new trends and technologies in the area of computer-assisted surgery. Finally, a balancing of the key challenges and possible benefits of endoscopic navigation refines the perspectives of this increasingly important discipline of computer-aided medical procedures. PMID:18366319

  10. Navigation in endoscopic soft tissue surgery: perspectives and limitations.

    PubMed

    Baumhauer, Matthias; Feuerstein, Marco; Meinzer, Hans-Peter; Rassweiler, J

    2008-04-01

    Despite rapid developments in the research areas of medical imaging, medical image processing, and robotics, the use of computer assistance in surgical routine is still limited to diagnostics, surgical planning, and interventions on mostly rigid structures. In order to establish a computer-aided workflow from diagnosis to surgical treatment and follow-up, several proposals for computer-assisted soft tissue interventions have been made in recent years. By means of different pre- and intraoperative information sources, such as surgical planning, intraoperative imaging, and tracking devices, surgical navigation systems aim to support surgeons in localizing anatomical targets, observing critical structures, and sparing healthy tissue. Current research in particular addresses the problem of organ shift and tissue deformation, and obstacles in communication between navigation system and surgeon. In this paper, we review computer-assisted navigation systems for soft tissue surgery. We concentrate on approaches that can be applied in endoscopic thoracic and abdominal surgery, because endoscopic surgery has special needs for image guidance due to limitations in perception. Furthermore, this paper informs the reader about new trends and technologies in the area of computer-assisted surgery. Finally, a balancing of the key challenges and possible benefits of endoscopic navigation refines the perspectives of this increasingly important discipline of computer-aided medical procedures.

  11. Knowledge-aided multisensor data fusion for maritime surveillance

    NASA Astrophysics Data System (ADS)

    Battistello, Giulia; Ulmke, Martin; Koch, Wolfgang

    2011-06-01

    Multi sensor fusion techniques are widely employed in several surveillance applications (e.g., battlefield monitoring, air traffic control, camp protection, etc). The necessity of tracking the elements of a dynamic system usually requires combining information from heterogeneous data sources in order to overcome the limitations of each sensor. The gathered information might be related to the target kinematics (position, velocity), its physical features (shape, size, composition) or intentions (route plan, friend/foe, engaged sensor modes, etc). The combination of such heterogeneous sensor data proved to benefit from the exploitation of context information, i.e., static and dynamic features of the scenario, represented in a Knowledge Base (KB). A Geographic Information System (GIS) is a typical example for a KB that can be exploited for the enhancement of multi sensor data fusion. The present paper describes potential strategies for "knowledge-based" data fusion in the area of Maritime Situational Awareness (MSA). MSA is founded on the data from heterogeneous sources, including radars, Navigation Aids, air- and space-based monitoring services, and recently-conceived passive sensors. Several strategies for optimally fusing two or more of these information data flows have been proposed for MSA applications. Relevant KB information comprises port locations, coastal lines, preferred routes, traffic rules, and potentially a maritime vessel database. We propose mathematical models and techniques to integrate kinematic constraints, e.g., in terms of navigation fields, and different object behaviour into a data fusion approach. For an exemplary sensor suite, we evaluate performance measures in the framework of centralised and decentralised fusion architectures.

  12. Space Weather Effects on Aircraft Navigation

    NASA Astrophysics Data System (ADS)

    Stanley, J. C.; Cade, W. B.

    2012-12-01

    Many aircraft today use satellites for GPS navigation, arrival and departure to and from airspaces, and for "shooting" non-precision and precision Instrument Approaches into airports. Also in development is an Air Traffic Control system based on satellite technology that seeks to modernize current air traffic control and improve safety, eventually phasing out radar (though not yet in the very near future). Due to the general, commercial, and military aviation fields all becoming more and more reliant on satellite and GPS technologies, the effects of space weather events on these systems is of paramount concern to militaries, airlines, private pilots, and other aviation operators. In this study we analyze data from airlines and other resources regarding effects on satellite and GPS systems, which is crucial to the conduct of safe flight operations now and improving systems for future and continued use.

  13. Remote sensing aides studies of climate and wildlife in the Arctic-on land, at sea, and in the air (Invited)

    NASA Astrophysics Data System (ADS)

    Douglas, D. C.; Durner, G. M.; Gill, R. E.; Griffith, B.; Schmutz, J. A.

    2013-12-01

    Every day a variety of remote sensing technologies collects large volumes of data that are supporting new analyses and new interpretations about how weather and climate influence the status and distribution of wildlife populations worldwide. Understanding how climate presently affects wildlife is crucial for projecting how climate change could affect wildlife in the future. This talk highlights climate-related wildlife studies by the US Geological Survey in the Arctic. The Arctic is experiencing some of the most pronounced climate changes on earth, raising concerns for species that have evolved seasonal migration strategies tuned to habitat availability and quality. On land, large herbivores such as caribou select concentrated calving areas with high abundance of rapidly growing vegetation and calf survival increases with earlier green-up and with the quantity of food available to cows at peak lactation. Geese time their migrations and reproductive efforts to coincide with optimal plant phenology and peak nutrient availability and departures from this synchrony can influence the survival of goslings. At sea, the habitats of polar bears and other sea-ice-dependent species have dramatically changed over just the past two decades. The ice pack is comprised of younger ice that melts much more extensively during summer-a trend projected to continue by all general circulation models under all but the most aggressive greenhouse gas mitigation scenarios. Studies show that by mid-century optimal polar bear habitats will be so reduced that the species may become extirpated from some regions of the Arctic. In the air, a variety of shorebird species make non-stop endurance flights between northern and southern hemispheres. The bar-tailed godwit undertakes a trans-Pacific flight between Alaska and Australasia that lasts more than seven days and spans more than 10,000 km. Studies show that godwits time their flights to coincide with favorable wind conditions, but stochastic

  14. Navigation: Traveling the Water Highways.

    ERIC Educational Resources Information Center

    Fisher, Marion; Lane, Jack

    1995-01-01

    One of the most important yet often overlooked uses of water is as a method of transportation or, navigation. Presents an activity to help students understand the importance of water as a critical, renewable, and natural resource for navigational use. Lists the learning objective, materials, and procedure for the activity. Also includes a foldout.…

  15. Navigating the Seas of Policy.

    ERIC Educational Resources Information Center

    Cunningham, Stephanie; Kennedy, Steve; McAlonan, Susan; Hotchkiss, Heather

    As the sun, moon, and stars helped sea captains to navigate, policy (defined as a formalized idea to encourage change) indicates general direction and speed but does not establish a specific approach to achieve implementation. Formal and informal policies have advantages and disadvantages. These are steps in navigating policy formation: identify…

  16. Introductory Course on Satellite Navigation

    ERIC Educational Resources Information Center

    Giger, Kaspar; Knogl, J. Sebastian

    2012-01-01

    Satellite navigation is widely used for personal navigation and more and more in precise and safety-critical applications. Thus, the subject is suited for attracting the interest of young people in science and engineering. The practical applications allow catching the students' attention for the theoretical background. Educational material on the…

  17. Celestial Navigation in the 21st Century

    NASA Astrophysics Data System (ADS)

    Kaplan, George H.

    2014-05-01

    Despite the ubiquity of GPS receivers in modern life for both timekeeping and geolocation, other forms of navigation remain important because of the weakness of the GPS signals (and those from similar sat-nav systems) and the ease with which they can be jammed. GPS jammers are available for sale on the Internet. The defense and civil aviation communities are particularly concerned about “GPS denial”, whether intentional or accidental, during critical operations.Automated star trackers for navigation have been available since the 1950s. Modern compact observing systems, operating in the far-red and near-IR bands, can detect useful numbers of stars even in the daytime at sea level. A capability to measure the directions of stars relative to some local set of coordinate axes is advantageous for many types of vehicles, whether on the ground, at sea, in the air, or in space, because it provides a direct connection to the inertial reference system represented by current star catalogs. Such a capability can yield precise absolute orientation information not available in any other way. Automated celestial observing systems can be effectively coupled to inertial navigation systems (INS), providing “truth” data for constraining the drift in the INS navigation solution, even if stellar observations are not continuously available due to weather. However, obtaining precise latitude and longitude from stellar observations alone, on a moving platform, remains a challenge, because it requires a determination of the direction to the center of the Earth, i.e., the gravity vertical. General relativity tells us that on-board (“lab”) measurements cannot separate the acceleration of gravity from the acceleration of the platform. Various schemes for overcoming this fundamental problem have been used in the past, at low accuracy, and better ones have been proposed for modern applications. This paper will review some recent developments in this rapidly advancing field.

  18. Endoscopic navigation for minimally invasive suturing.

    PubMed

    Wengert, Christian; Bossard, Lukas; Häberling, Armin; Baur, Charles; Székely, Gábor; Cattin, Philippe C

    2007-01-01

    Manipulating small objects such as needles, screws or plates inside the human body during minimally invasive surgery can be very difficult for less experienced surgeons, due to the loss of 3D depth perception. This paper presents an approach for tracking a suturing needle using a standard endoscope. The resulting pose information of the needle is then used to generate artificial 3D cues on the 2D screen to optimally support surgeons during tissue suturing. Additionally, if an external tracking device is provided to report the endoscope's position, the suturing needle can be tracked in a hybrid fashion with sub-millimeter accuracy. Finally, a visual navigation aid can be incorporated, if a 3D surface is intraoperatively reconstructed from video or registered from preoperative imaging. PMID:18044620

  19. Endoscopic navigation for minimally invasive suturing.

    PubMed

    Wengert, Christian; Bossard, Lukas; Häberling, Armin; Baur, Charles; Székely, Gábor; Cattin, Philippe C

    2007-01-01

    Manipulating small objects such as needles, screws or plates inside the human body during minimally invasive surgery can be very difficult for less experienced surgeons, due to the loss of 3D depth perception. This paper presents an approach for tracking a suturing needle using a standard endoscope. The resulting pose information of the needle is then used to generate artificial 3D cues on the 2D screen to optimally support surgeons during tissue suturing. Additionally, if an external tracking device is provided to report the endoscope's position, the suturing needle can be tracked in a hybrid fashion with sub-millimeter accuracy. Finally, a visual navigation aid can be incorporated, if a 3D surface is intraoperatively reconstructed from video or registered from preoperative imaging.

  20. The real-world navigator

    NASA Technical Reports Server (NTRS)

    Balabanovic, Marko; Becker, Craig; Morse, Sarah K.; Nourbakhsh, Illah R.

    1994-01-01

    The success of every mobile robot application hinges on the ability to navigate robustly in the real world. The problem of robust navigation is separable from the challenges faced by any particular robot application. We offer the Real-World Navigator as a solution architecture that includes a path planner, a map-based localizer, and a motion control loop that combines reactive avoidance modules with deliberate goal-based motion. Our architecture achieves a high degree of reliability by maintaining and reasoning about an explicit description of positional uncertainty. We provide two implementations of real-world robot systems that incorporate the Real-World Navigator. The Vagabond Project culminated in a robot that successfully navigated a portion of the Stanford University campus. The Scimmer project developed successful entries for the AIAA 1993 Robotics Competition, placing first in one of the two contests entered.

  1. Mortality among US commercial pilots and navigators.

    PubMed

    Nicholas, J S; Lackland, D T; Dosemeci, M; Mohr, L C; Dunbar, J B; Grosche, B; Hoel, D G

    1998-11-01

    The airline industry may be an occupational setting with specific health risks. Two environmental agents to which flight crews are known to be exposed are cosmic radiation and magnetic fields generated by the aircraft's electrical system. Other factors to be considered are circadian disruption and conditions specific to air travel, such as noise, vibration, mild hypoxia, reduced atmospheric pressure, low humidity, and air quality. This study investigated mortality among US commercial pilots and navigators, using proportional mortality ratios for cancer and noncancer end points. Proportional cancer mortality ratios and mortality odds ratios were also calculated for comparison to the proportional mortality ratios for cancer causes of death. Results indicated that US pilots and navigators have experienced significantly increased mortality due to cancer of the kidney and renal pelvis, motor neuron disease, and external causes. In addition, increased mortality due to prostate cancer, brain cancer, colon cancer, and cancer of the lip, buccal cavity, and pharynx was suggested. Mortality was significantly decreased for 11 causes. To determine if these health outcomes are related to occupational exposures, it will be necessary to quantify each exposure separately, to study the potential synergy of effects, and to couple this information with disease data on an individual basis. PMID:9830605

  2. Mortality among US commercial pilots and navigators.

    PubMed

    Nicholas, J S; Lackland, D T; Dosemeci, M; Mohr, L C; Dunbar, J B; Grosche, B; Hoel, D G

    1998-11-01

    The airline industry may be an occupational setting with specific health risks. Two environmental agents to which flight crews are known to be exposed are cosmic radiation and magnetic fields generated by the aircraft's electrical system. Other factors to be considered are circadian disruption and conditions specific to air travel, such as noise, vibration, mild hypoxia, reduced atmospheric pressure, low humidity, and air quality. This study investigated mortality among US commercial pilots and navigators, using proportional mortality ratios for cancer and noncancer end points. Proportional cancer mortality ratios and mortality odds ratios were also calculated for comparison to the proportional mortality ratios for cancer causes of death. Results indicated that US pilots and navigators have experienced significantly increased mortality due to cancer of the kidney and renal pelvis, motor neuron disease, and external causes. In addition, increased mortality due to prostate cancer, brain cancer, colon cancer, and cancer of the lip, buccal cavity, and pharynx was suggested. Mortality was significantly decreased for 11 causes. To determine if these health outcomes are related to occupational exposures, it will be necessary to quantify each exposure separately, to study the potential synergy of effects, and to couple this information with disease data on an individual basis.

  3. BAHA: Bone-Anchored Hearing Aid

    PubMed Central

    Hagr, Abdulrahman

    2007-01-01

    Bone-Anchored Hearing Aid (BAHA) has proven performance and advantages for patients with aural atresia or chronic ear drainage who cannot wear air-conduction hearing aids. The BAHA has both cosmetic and acoustic advantages over most conventional hearing aids and hence is becoming increasingly popular. Moreover, BAHA improves the quality of life and has also significantly reduces ear discharge. This extensive review of the literature pertaining to BAHA discus the history, the indications, the advantages, the prediction of the outcome and the complications of this device as well as comparing it to the conventional hearing aids. PMID:21475438

  4. The navigation of homing pigeons: Do they use sun Navigation?

    NASA Technical Reports Server (NTRS)

    Walcott, C.

    1972-01-01

    Experiments to determine the dependence of homing pigeons on the sun as a navigational cue are discussed. Various methods were employed to interrupt the circadian rhythms of the pigeons prior to release. It was determined that the sun may serve as a compass, but that topographic features are more important for navigation. The effects of a magnetic field produced by electric equipment carried by the bird were also investigated. It was concluded that magnetic fields may have a small effect on the homing ability. The exact nature of the homing pigeon's navigational ability is still unknown after years of elaborate experimentation.

  5. Software for Simulating Air Traffic

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar; Bilimoria, Karl; Grabbe, Shon; Chatterji, Gano; Sheth, Kapil; Mulfinger, Daniel

    2006-01-01

    Future Air Traffic Management Concepts Evaluation Tool (FACET) is a system of software for performing computational simulations for evaluating advanced concepts of advanced air-traffic management. FACET includes a program that generates a graphical user interface plus programs and databases that implement computational models of weather, airspace, airports, navigation aids, aircraft performance, and aircraft trajectories. Examples of concepts studied by use of FACET include aircraft self-separation for free flight; prediction of air-traffic-controller workload; decision support for direct routing; integration of spacecraft-launch operations into the U.S. national airspace system; and traffic- flow-management using rerouting, metering, and ground delays. Aircraft can be modeled as flying along either flight-plan routes or great-circle routes as they climb, cruise, and descend according to their individual performance models. The FACET software is modular and is written in the Java and C programming languages. The architecture of FACET strikes a balance between flexibility and fidelity; as a consequence, FACET can be used to model systemwide airspace operations over the contiguous U.S., involving as many as 10,000 aircraft, all on a single desktop or laptop computer running any of a variety of operating systems. Two notable applications of FACET include: (1) reroute conformance monitoring algorithms that have been implemented in one of the Federal Aviation Administration s nationally deployed, real-time, operational systems; and (2) the licensing and integration of FACET with the commercially available Flight Explorer, which is an Internet- based, real-time flight-tracking system.

  6. Evolving earth-based and in-situ satellite network architectures for Mars communications and navigation support

    NASA Technical Reports Server (NTRS)

    Hastrup, Rolf; Weinberg, Aaron; Mcomber, Robert

    1991-01-01

    Results of on-going studies to develop navigation/telecommunications network concepts to support future robotic and human missions to Mars are presented. The performance and connectivity improvements provided by the relay network will permit use of simpler, lower performance, and less costly telecom subsystems for the in-situ mission exploration elements. Orbiting relay satellites can serve as effective navigation aids by supporting earth-based tracking as well as providing Mars-centered radiometric data for mission elements approaching, in orbit, or on the surface of Mars. The relay satellite orbits may be selected to optimize navigation aid support and communication coverage for specific mission sets.

  7. The navigation toolkit

    NASA Technical Reports Server (NTRS)

    Rich, William F.; Strom, Stephen W.

    1994-01-01

    This report summarizes the experience of the authors in managing, designing, and implementing an object-oriented applications framework for orbital navigation analysis for the Flight Design and Dynamics Department of the Rockwell Space Operations Company in Houston, in support of the Mission Operations Directorate of NASA's Johnson Space Center. The 8 person year project spanned 1.5 years and produced 30,000 lines of C++ code, replacing 150,000 lines of Fortran/C. We believe that our experience is important because it represents a 'second project' experience and generated real production-quality code - it was not a pilot. The project successfully demonstrated the use of 'continuous development' or rapid prototyping techniques. Use of formal methods and executable models contributed to the quality of the code. Keys to the success of the project were a strong architectural vision and highly skilled workers. This report focuses on process and methodology, and not on a detailed design description of the product. But the true importance of the object-oriented paradigm is its liberation of the developer to focus on the problem rather than the means used to solve the problem.

  8. Pedicle screw placement with O-arm and stealth navigation.

    PubMed

    Patil, Suresh; Lindley, Emily M; Burger, Evalina L; Yoshihara, Hiroyuki; Patel, Vikas V

    2012-01-16

    Various navigation systems are available to aid pedicle screw placement. The O-arm replaces the need for fluoroscopy and generates a 3-dimensional volumetric dataset that can be viewed as transverse, coronal, and sagittal images of the spine, similar to computed tomography (CT) scanning. The dataset can be downloaded to the Stealth system (Medtronic Navigation, Louisville, Colorado) for real-time intraoperative navigation.The main objectives of the current study were to assess (1) accuracy of pedicle screw placement using the O-arm/Stealth system, and (2) time for draping, positioning of the O-arm, and screw placement. Of 188 screws (25 patients), 116 had adequate images for analysis. The average time for O-arm draping was 3.5 minutes. Initial O-arm positioning was 6.1 minutes, and final positioning was 4.9 minutes. Mean time for screw placement, including O-arm draping and positioning and array attachment, was 8.1 minutes per screw. Mean time for screw placement alone was 5.9 minutes per screw. Screw placements on final O-arm images were on average 3.14 mm deeper than on the snapshot navigation images. Three screws (2.6%) breached the medial cortex, and 3 screws (2.6%) were misaligned and did not follow the pilot hole trajectory.The use of the O-arm/Stealth system was associated with a low rate of pedicle screw misalignment. The time to place screws was less than previously reported with CT navigation, but longer than conventional techniques. It is important to be aware of the potential discrepancy between snapshot navigation images and actual screw placement on final O-arm images. Our findings suggest that final screw positions may be deeper than awl positions appear on navigation images.

  9. Manufacturing Aids

    NASA Technical Reports Server (NTRS)

    1989-01-01

    During a research program, MMTC/Textron invented a computer-aided automatic robotic system for spraying hot plasma onto a turbine blade. The need to control the thickness of the plasma deposit led to the development of advanced optical gaging techniques to monitor and control plasma spray build-up on blade surfaces. The techniques led to computerized optical gages for inspecting aircraft, industrial turbine blades, etc. MMTC offers 10 standard commercial robotic gages. The system also generates two dimensional profiles for assessing status and specifying repairs to the electromechanical cathodes used to make the parts. It is capable of accuracies to a ten-thousandth of an inch. An expanded product line is currently marketed. The gages offer multiple improvements in quality control and significant savings.

  10. 14 CFR 121.389 - Flight navigator and specialized navigation equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Flight navigator and specialized navigation....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an... flight navigator certificate; or (2) Specialized means of navigation approved in accordance with §...

  11. 14 CFR 121.389 - Flight navigator and specialized navigation equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight navigator and specialized navigation....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an... flight navigator certificate; or (2) Specialized means of navigation approved in accordance with §...

  12. 14 CFR 121.389 - Flight navigator and specialized navigation equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Flight navigator and specialized navigation....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an... flight navigator certificate; or (2) Specialized means of navigation approved in accordance with §...

  13. 14 CFR 121.389 - Flight navigator and specialized navigation equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Flight navigator and specialized navigation....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an... flight navigator certificate; or (2) Specialized means of navigation approved in accordance with §...

  14. 14 CFR 121.389 - Flight navigator and specialized navigation equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Flight navigator and specialized navigation....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an... flight navigator certificate; or (2) Specialized means of navigation approved in accordance with §...

  15. Lunar Navigation Architecture Design Considerations

    NASA Technical Reports Server (NTRS)

    D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

    2009-01-01

    The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

  16. Multi-aircraft dynamics, navigation and operation

    NASA Astrophysics Data System (ADS)

    Houck, Sharon Wester

    Air traffic control stands on the brink of a revolution. Fifty years from now, we will look back and marvel that we ever flew by radio beacons and radar alone, much as we now marvel that early aviation pioneers flew by chronometer and compass alone. The microprocessor, satellite navigation systems, and air-to-air data links are the technical keys to this revolution. Many airports are near or at capacity now for at least portions of the day, making it clear that major increases in airport capacity will be required in order to support the projected growth in air traffic. This can be accomplished by adding airports, adding runways at existing airports, or increasing the capacity of the existing runways. Technology that allows use of ultra closely spaced (750 ft to 2500 ft) parallel approaches would greatly reduce the environmental impact of airport capacity increases. This research tackles the problem of multi aircraft dynamics, navigation, and operation, specifically in the terminal area, and presents new findings on how ultra closely spaced parallel approaches may be accomplished. The underlying approach considers how multiple aircraft are flown in visual conditions, where spacing criteria is much less stringent, and then uses this data to study the critical parameters for collision avoidance during an ultra closely spaced parallel approach. Also included is experimental and analytical investigations on advanced guidance systems that are critical components of precision approaches. Together, these investigations form a novel approach to the design and analysis of parallel approaches for runways spaced less than 2500 ft apart. This research has concluded that it is technically feasible to reduce the required runway spacing during simultaneous instrument approaches to less than the current minimum of 3400 ft with the use of advanced navigation systems while maintaining the currently accepted levels of safety. On a smooth day with both pilots flying a tunnel

  17. 33 CFR 334.560 - Banana River at Patrick Air Force Base, Fla.; restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Banana River at Patrick Air Force Base, Fla.; restricted area. 334.560 Section 334.560 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.560...

  18. 33 CFR 334.560 - Banana River at Patrick Air Force Base, Fla.; restricted area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Banana River at Patrick Air Force Base, Fla.; restricted area. 334.560 Section 334.560 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.560...

  19. 33 CFR 334.560 - Banana River at Patrick Air Force Base, Fla.; restricted area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Banana River at Patrick Air Force Base, Fla.; restricted area. 334.560 Section 334.560 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.560...

  20. 33 CFR 334.560 - Banana River at Patrick Air Force Base, Fla.; restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Banana River at Patrick Air Force Base, Fla.; restricted area. 334.560 Section 334.560 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.560...