Evaluation of STOL navigation avionics

NASA Technical Reports Server (NTRS)

Dunn, W. R., Jr.

1977-01-01

Research projects, including work on a vector magnetometer for aircraft attitude measurement, are summarized. The earth's electric field phenomena was investigated in its application to aircraft control and navigation. Research on electronic aircraft cabin noise suppression is reviewed and strapdown inertial reference unit technical support is outlined.

Graphical overview and navigation of electronic health records in a prototyping environment using Google Earth and openEHR archetypes.

PubMed

Sundvall, Erik; Nyström, Mikael; Forss, Mattias; Chen, Rong; Petersson, Håkan; Ahlfeldt, Hans

2007-01-01

This paper describes selected earlier approaches to graphically relating events to each other and to time; some new combinations are also suggested. These are then combined into a unified prototyping environment for visualization and navigation of electronic health records. Google Earth (GE) is used for handling display and interaction of clinical information stored using openEHR data structures and 'archetypes'. The strength of the approach comes from GE's sophisticated handling of detail levels, from coarse overviews to fine-grained details that has been combined with linear, polar and region-based views of clinical events related to time. The system should be easy to learn since all the visualization styles can use the same navigation. The structured and multifaceted approach to handling time that is possible with archetyped openEHR data lends itself well to visualizing and integration with openEHR components is provided in the environment.

Precision Time Protocol-Based Trilateration for Planetary Navigation

NASA Technical Reports Server (NTRS)

Murdock, Ron

2015-01-01

Progeny Systems Corporation has developed a high-fidelity, field-scalable, non-Global Positioning System (GPS) navigation system that offers precision localization over communications channels. The system is bidirectional, providing position information to both base and mobile units. It is the first-ever wireless use of the Institute of Electrical and Electronics Engineers (IEEE) Precision Time Protocol (PTP) in a bidirectional trilateration navigation system. The innovation provides a precise and reliable navigation capability to support traverse-path planning systems and other mapping applications, and it establishes a core infrastructure for long-term lunar and planetary occupation. Mature technologies are integrated to provide navigation capability and to support data and voice communications on the same network. On Earth, the innovation is particularly well suited for use in unmanned aerial vehicles (UAVs), as it offers a non-GPS precision navigation and location service for use in GPS-denied environments. Its bidirectional capability provides real-time location data to the UAV operator and to the UAV. This approach optimizes assisted GPS techniques and can be used to determine the presence of GPS degradation, spoofing, or jamming.

National aerospace meeting of the Institute of Navigation

NASA Astrophysics Data System (ADS)

Fell, Patrick

The program for this year's aerospace meeting of The Institute of Navigation addressed developments in the evolving Global Positioning System (GPS) of navigation satellites, inertial navigation systems, and other electronic navigation systems and their applications. Also included in the program were a limited number of papers addressing the geodetic use of the GPS system.The Global Positioning System is a constellation of 18 navigation satellites being developed by the Department of Defense to provide instantaneous worldwide navigation. The system will support a multitude of military applications. The first paper by Jacobson reviewed the engineering development of GPS navigation receivers stressing the use of common hardware and software modules. A later paper by Ould described the mechanization of a digital receiver for GPS applications designed for faster acquisition of the spread spectrum satellite transmissions than analog receivers. The paper by Brady discussed the worldwide coverage that is provided by the limited number of satellites that will constitute the GPS constellation through 1983. The capability provided by the satellites presently on orbit would support a variety of experiments at almost any location. Tables of multiple satellite availability are provided for numerous worldwide locations. For civil aviation applications, Vogel addressed the satellite geometry considerations for low cost GPS user equipment, Esposito described the Federal Aviation Administration acceptance tests of a GPS navigation receiver, and Hopkins discussed the design and capability of an integrated GPS strapdown attitude and heading reference system for avionics.

Navigation.

PubMed

Wiltschko, Roswitha

2017-07-01

Experiments with migrating birds displaced during autumn migration outside their normal migration corridor reveal two different navigational strategies: adult migrants compensate for the displacement, and head towards their traditional wintering areas, whereas young first-time migrants continue in their migratory direction. Young birds are guided to their still unknown goal by a genetically coded migration program that indicates duration and direction(s) of the migratory flight by controlling the amount of migratory restlessness and the compass course(s) with respect to the geomagnetic field and celestial rotation. Adult migrants that have already wintered and are familiar with the goal area approach the goal by true navigation, specifically heading towards it and changing their course correspondingly after displacement. During their first journey, young birds experience the distribution of potential navigational factors en route and in their winter home, which allows them to truly navigate on their next migrations. The navigational factors used appear to include magnetic intensity as a component in their multi-modal navigational 'map'; olfactory input is also involved, even if it is not yet entirely clear in what way. The mechanisms of migratory birds for true navigation over long distances appear to be in principle similar to those discussed for by homing pigeons.

New Magnetospheric Substorm Injection Monitor: Image Electron Spectrometer On Board a Chinese Navigation IGSO Satellite

NASA Astrophysics Data System (ADS)

Zong, Qiugang; Wang, Yongfu; Zou, Hong; Wang, Linghua; Rankin, Robert; Zhang, Xiaoxin

2018-02-01

Substorm injections are one of the most dynamic processes in Earth's magnetosphere and have global consequences and broad implications for space weather modeling. They can be monitored using energetic electron detectors on geosynchronous satellites. The Imaging Electron Spectrometer (IES) on board a Chinese navigation satellite, launched on 16 October 2015 into an inclined geosynchronous satellite orbit (IGSO), provides the first energetic electron measurement in IGSO orbit to the best of our knowledge. The IES was developed by Peking University and is named hereafter as BD-IES. Using a pin-hole technique, the BD-IES instrument measures 50-600 keV incident electrons in eight energy channels from nine directions covering a range of 180° in polar angle. Data collection by the BD-IES instrument have recently passed the 1 year mark, which reflects a successful milestone for the mission. The innermost and outermost signatures of substorm injection at L 6 and 12 have been observed by the BD-IES with a high L shell spatial coverage, complementary to the existing missions such as the Van Allen Probes that covers the range below L 6. There are another two BD-IES instruments to be installed in the coming Chinese Sun-synchronous and geosynchronous satellites, respectively. Such a configuration will provide a unique opportunity to investigate inward and outward radial propagation of the substorm injection region simultaneously at high and low L shells. It will further elucidate potential mechanisms for the particle energization and transport, two of the most important topics in magnetospheric dynamics.

SURVIVORSHIP NAVIGATION OUTCOME MEASURES: A report from the ACS Patient Navigation Working Group on Survivorship Navigation

PubMed Central

Pratt-Chapman, Mandi; Simon, Melissa A.; Patterson, Angela; Risendal, Betsy C.; Patierno, Steven

2013-01-01

Survivorship navigation is a relatively new concept in the field of patient navigation, but an important one. This paper highlights the essential functions of the survivorship navigator and defines core outcomes and measures for navigation in the survivorship period. Barriers to access to care experienced by patients during active cancer treatment can continue into the post-treatment period, affecting quality follow-up care for survivors. These barriers to care can be particularly acute for non-English speakers, immigrants, the uninsured, the underinsured and other vulnerable populations. The survivorship navigator can help reduce barriers and facilitate access to survivorship care and services through communication and information exchange for patients. Survivorship navigation may improve appropriate health care utilization through education and care coordination, potentially improving health outcomes and quality of life of survivors while reducing cost to the health care system. Survivorship navigators can also educate survivors on how to improve their overall wellness, thereby directly impacting the health of a growing population of cancer survivors. PMID:21780092

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 equipment. 121.389 Section 121.389 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an...

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 equipment. 121.389 Section 121.389 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an...

PATIENT NAVIGATION

PubMed Central

Wells, Kristen J.; Battaglia, Tracy A.; Dudley, Donald J.; Garcia, Roland; Greene, Amanda; Calhoun, Elizabeth; Mandelblatt, Jeanne S.; Paskett, Electra D.; Raich, Peter C.

2008-01-01

Background First implemented in 1990, patient navigation interventions are emerging as an approach to reduce cancer disparities. However, there is lack of consensus about how patient navigation is defined, what patient navigators do, and what their qualifications should be. Little is known about the efficacy and cost effectiveness of patient navigation. Methods We conducted a qualitative synthesis of published literature on cancer patient navigation. Using the keywords “navigator” or “navigation” and “cancer,” we identified 45 articles from Pubmed and reference searches that were published or in press through October 2007. 16 provided data on efficacy of navigation in improving timeliness and receipt of cancer screening, diagnostic follow-up care, and treatment. Patient navigation services are defined and differentiated from other outreach services. Results Overall there is evidence for some degree of efficacy for patient navigation in increasing participation in cancer screening and adherence to diagnostic follow-up care following an abnormality, with increases in screening ranging from 10.8% to 17.1% and increases in adherence to diagnostic follow-up care ranging from 21% to 29.2%, when compared to control patients. There is less evidence regarding efficacy of patient navigation in reducing either late stage cancer diagnosis or delays in initiation of cancer treatment or improving outcomes during cancer survivorship. There were methodological limitations in most studies, such as lack of control groups, small sample sizes, and contamination with other interventions. Conclusions Although cancer-related patient navigation interventions are being increasingly adopted across the U.S. and Canada, further research is necessary to evaluate their efficacy and cost-effectiveness in improving cancer care. PMID:18780320

Area navigation and required navigation performance procedures and depictions

DOT National Transportation Integrated Search

2012-09-30

Area navigation (RNAV) and required navigation performance (RNP) procedures are fundamental to the implementation of a performance based navigation (PBN) system, which is a key enabling technology for the Next Generation Air Transportation System (Ne...

Using Electronic Health Records to Enhance a Peer Health Navigator Intervention: A Randomized Pilot Test for Individuals with Serious Mental Illness and Housing Instability.

PubMed

Kelly, Erin L; Braslow, Joel T; Brekke, John S

2018-05-03

Individuals with serious mental illnesses have high rates of comorbid physical health issues and have numerous barriers to addressing their health and health care needs. The present pilot study tested the feasibility of a modified form of the "Bridge" peer-health navigator intervention delivered in a usual care setting by agency personnel. The modifications concerned the use of an electronic personal health record with individuals experiencing with housing instability. Twenty participants were randomized to receive the intervention immediately or after 6 months. Health navigator contacts and use of personal health records were associated with improvements in health care and self-management. This pilot study demonstrated promising evidence for the feasibility of adding personal health record use to a peer-led intervention.

Sex differences in virtual navigation influenced by scale and navigation experience.

PubMed

Padilla, Lace M; Creem-Regehr, Sarah H; Stefanucci, Jeanine K; Cashdan, Elizabeth A

2017-04-01

The Morris water maze is a spatial abilities test adapted from the animal spatial cognition literature and has been studied in the context of sex differences in humans. This is because its standard design, which manipulates proximal (close) and distal (far) cues, applies to human navigation. However, virtual Morris water mazes test navigation skills on a scale that is vastly smaller than natural human navigation. Many researchers have argued that navigating in large and small scales is fundamentally different, and small-scale navigation might not simulate natural human navigation. Other work has suggested that navigation experience could influence spatial skills. To address the question of how individual differences influence navigational abilities in differently scaled environments, we employed both a large- (146.4 m in diameter) and a traditional- (36.6 m in diameter) scaled virtual Morris water maze along with a novel measure of navigation experience (lifetime mobility). We found sex differences on the small maze in the distal cue condition only, but in both cue-conditions on the large maze. Also, individual differences in navigation experience modulated navigation performance on the virtual water maze, showing that higher mobility was related to better performance with proximal cues for only females on the small maze, but for both males and females on the large maze.

Building the Traffic, Navigation, and Situation Awareness System (T-NASA) for Surface Operations

NASA Technical Reports Server (NTRS)

McCann, Robert S.

1996-01-01

We report the results of a part-task simulation evaluating the separate and combined effects of an electronic moving map display and newly developed HUD symbology on ground taxi performance, under moderate- and low-visibility conditions. Twenty-four commercial airline pilots carried out a series of 28 gate-to-runway taxi trials at Chicago O'Hare. Half of the trials were conducted under moderate visibility (RVR 1400 ft), and half under low visibility (RVR 700 ft). In the baseline condition, where navigation support was limited to surface features and a Jeppesen paper map, navigation errors were committed on almost half of the trials. These errors were virtually abolished when the electronic moving map or the HUD symbology was available; in addition, compare, the baseline condition, both forms of navigation aid yielded an increase in forward taxi speed. The speed increase was greater for HUD than the electronic moving map, and greater under low visibility than under moderate visibility. These results suggest that combination of electronic moving map and HUD symbology has the potential to greatly increase the efficiency of ground operations, particularly under low-visibility conditions.

Interplanetary navigation

NASA Technical Reports Server (NTRS)

Stuart, J. R.

1984-01-01

The evolution of NASA's planetary navigation techniques is traced, and radiometric and optical data types are described. Doppler navigation; the Deep Space Network; differenced two-way range techniques; differential very long base interferometry; and optical navigation are treated. The Doppler system enables a spacecraft in cruise at high absolute declination to be located within a total angular uncertainty of 1/4 microrad. The two-station range measurement provides a 1 microrad backup at low declinations. Optical data locate the spacecraft relative to the target to an angular accuracy of 5 microrad. Earth-based radio navigation and its less accurate but target-relative counterpart, optical navigation, thus form complementary measurement sources, which provide a powerful sensory system to produce high-precision orbit estimates.

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.

SEXTANT X-Ray Pulsar Navigation Demonstration: Flight System and Test Results

NASA Technical Reports Server (NTRS)

Winternitz, Luke; Mitchell, Jason W.; Hassouneh, Munther A.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Ray, Paul S.; Wood, Kent S.; Arzoumanian, Zaven;

SEXTANT X-Ray Pulsar Navigation Demonstration: Flight System and Test Results

NASA Technical Reports Server (NTRS)

Winternitz, Luke M. B.; Mitchell, Jason W.; Hassouneh, Munther A.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Ray, Paul S.; Wood, Kent S.; Arzoumanian, Zaven;

Development of a chronic kidney disease patient navigator program.

PubMed

Jolly, Stacey E; Navaneethan, Sankar D; Schold, Jesse D; Arrigain, Susana; Konig, Victoria; Burrucker, Yvette K; Hyland, Jennifer; Dann, Priscilla; Tucky, Barbara H; Sharp, John W; Nally, Joseph V

2015-05-03

Chronic Kidney Disease (CKD) is a public health problem and there is a scarcity of type 2 CKD translational research that incorporates educational tools. Patient navigators have been shown to be effective at reducing disparities and improving outcomes in the oncology field. We describe the creation of a CKD Patient Navigator program designed to help coordinate care, address system-barriers, and educate/motivate patients. The conceptual framework for the CKD Patient Navigator Program is rooted in the Chronic Care Model that has a main goal of high-quality chronic disease management. Our established multidisciplinary CKD research team enlisted new members from information technology and data management to help create the program. It encompassed three phases: hiring, training, and implementation. For hiring, we wanted a non-medical or lay person with a college degree that possessed strong interpersonal skills and experience in a service-orientated field. For training, there were three key areas: general patient navigator training, CKD education, and electronic health record (EHR) training. For implementation, we defined barriers of care and created EHR templates for which pertinent study data could be extracted. We have hired two CKD patient navigators who will be responsible for navigating CKD patients enrolled in a clinical trial. They have undergone training in general patient navigation, specific CKD education through directed readings and clinical shadowing, as well as EHR and other patient related privacy and research training. The need for novel approaches like our CKD patient navigator program designed to impact CKD care is vital and should utilize team-based care and health information technology given the changing landscape of our health systems.

Space shuttle navigation analysis. Volume 2: Baseline system navigation

NASA Technical Reports Server (NTRS)

Jones, H. L.; Luders, G.; Matchett, G. A.; Rains, R. G.

1980-01-01

Studies related to the baseline navigation system for the orbiter are presented. The baseline navigation system studies include a covariance analysis of the Inertial Measurement Unit calibration and alignment procedures, postflight IMU error recovery for the approach and landing phases, on-orbit calibration of IMU instrument biases, and a covariance analysis of entry and prelaunch navigation system performance.

Modified Navigation Instructions for Spatial Navigation Assistance Systems Lead to Incidental Spatial Learning

PubMed Central

Gramann, Klaus; Hoepner, Paul; Karrer-Gauss, Katja

2017-01-01

Spatial cognitive skills deteriorate with the increasing use of automated GPS navigation and a general decrease in the ability to orient in space might have further impact on independence, autonomy, and quality of life. In the present study we investigate whether modified navigation instructions support incidental spatial knowledge acquisition. A virtual driving environment was used to examine the impact of modified navigation instructions on spatial learning while using a GPS navigation assistance system. Participants navigated through a simulated urban and suburban environment, using navigation support to reach their destination. Driving performance as well as spatial learning was thereby assessed. Three navigation instruction conditions were tested: (i) a control group that was provided with classical navigation instructions at decision points, and two other groups that received navigation instructions at decision points including either (ii) additional irrelevant information about landmarks or (iii) additional personally relevant information (i.e., individual preferences regarding food, hobbies, etc.), associated with landmarks. Driving performance revealed no differences between navigation instructions. Significant improvements were observed in both modified navigation instruction conditions on three different measures of spatial learning and memory: subsequent navigation of the initial route without navigation assistance, landmark recognition, and sketch map drawing. Future navigation assistance systems could incorporate modified instructions to promote incidental spatial learning and to foster more general spatial cognitive abilities. Such systems might extend mobility across the lifespan. PMID:28243219

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.

INL Autonomous Navigation System

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

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... § 207.185 Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation...

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... § 207.185 Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation...

Patient Navigation in Breast Cancer Treatment and Survivorship: A Systematic Review.

PubMed

Baik, Sharon H; Gallo, Linda C; Wells, Kristen J

2016-07-25

Patient navigation is an intervention approach that improves cancer outcomes by reducing barriers and facilitating timely access to cancer care. Little is known about the benefits of patient navigation during breast cancer treatment and survivorship. This systematic review evaluates the efficacy of patient navigation in improving treatment and survivorship outcomes in women with breast cancer. The review included experimental and quasi-experimental studies of patient navigation programs that target breast cancer treatment and breast cancer survivorship. Articles were systematically obtained through electronic database searches of PubMed/MEDLINE, PsycINFO, Web of Science, CINAHL, and Cochrane Library. The Effective Public Health Practice Project Quality Assessment Tool was used to evaluate the methodologic quality of individual studies. Thirteen studies met the inclusion criteria. Most were of moderate to high quality. Outcomes targeted included timeliness of treatment initiation, adherence to cancer treatment, and adherence to post-treatment surveillance mammography. Heterogeneity of outcome assessments precluded a meta-analysis. Overall, results demonstrated that patient navigation increases surveillance mammography rates, but only minimal evidence was found with regard to its effectiveness in improving breast cancer treatment outcomes. This study is the most comprehensive systematic review of patient navigation research focused on improving breast cancer treatment and survivorship. Minimal research has indicated that patient navigation may be effective for post-treatment surveillance; however, more studies are needed to draw definitive conclusions about the efficacy of patient navigation during and after cancer treatment. © 2016 by American Society of Clinical Oncology.

Patient Navigation in Breast Cancer Treatment and Survivorship: A Systematic Review

PubMed Central

Baik, Sharon H.; Gallo, Linda C.

2016-01-01

Purpose Patient navigation is an intervention approach that improves cancer outcomes by reducing barriers and facilitating timely access to cancer care. Little is known about the benefits of patient navigation during breast cancer treatment and survivorship. This systematic review evaluates the efficacy of patient navigation in improving treatment and survivorship outcomes in women with breast cancer. Methods The review included experimental and quasi-experimental studies of patient navigation programs that target breast cancer treatment and breast cancer survivorship. Articles were systematically obtained through electronic database searches of PubMed/MEDLINE, PsycINFO, Web of Science, CINAHL, and Cochrane Library. The Effective Public Health Practice Project Quality Assessment Tool was used to evaluate the methodologic quality of individual studies. Results Thirteen studies met the inclusion criteria. Most were of moderate to high quality. Outcomes targeted included timeliness of treatment initiation, adherence to cancer treatment, and adherence to post-treatment surveillance mammography. Heterogeneity of outcome assessments precluded a meta-analysis. Overall, results demonstrated that patient navigation increases surveillance mammography rates, but only minimal evidence was found with regard to its effectiveness in improving breast cancer treatment outcomes. Conclusion This study is the most comprehensive systematic review of patient navigation research focused on improving breast cancer treatment and survivorship. Minimal research has indicated that patient navigation may be effective for post-treatment surveillance; however, more studies are needed to draw definitive conclusions about the efficacy of patient navigation during and after cancer treatment. PMID:27458298

Navigable networks as Nash equilibria of navigation games.

PubMed

Gulyás, András; Bíró, József J; Kőrösi, Attila; Rétvári, Gábor; Krioukov, Dmitri

2015-07-03

Common sense suggests that networks are not random mazes of purposeless connections, but that these connections are organized so that networks can perform their functions well. One function common to many networks is targeted transport or navigation. Here, using game theory, we show that minimalistic networks designed to maximize the navigation efficiency at minimal cost share basic structural properties with real networks. These idealistic networks are Nash equilibria of a network construction game whose purpose is to find an optimal trade-off between the network cost and navigability. We show that these skeletons are present in the Internet, metabolic, English word, US airport, Hungarian road networks, and in a structural network of the human brain. The knowledge of these skeletons allows one to identify the minimal number of edges, by altering which one can efficiently improve or paralyse navigation in the network.

Autonomous Navigation Above the GNSS Constellations and Beyond: GPS Navigation for the Magnetospheric Multiscale Mission and SEXTANT Pulsar Navigation Demonstration

NASA Technical Reports Server (NTRS)

Winternitz, Luke

2017-01-01

This talk will describe two first-of-their-kind technology demonstrations attached to ongoing NASA science missions, both of which aim to extend the range of autonomous spacecraft navigation far from the Earth. First, we will describe the onboard GPS navigation system for the Magnetospheric Multiscale (MMS) mission which is currently operating in elliptic orbits reaching nearly halfway to the Moon. The MMS navigation system is a key outgrowth of a larger effort at NASA Goddard Space Flight Center to advance high-altitude Global Navigation Satellite System (GNSS) navigation on multiple fronts, including developing Global Positioning System receivers and onboard navigation software, running simulation studies, and leading efforts to characterize and protect signals at high-altitude in the so-called GNSS Space-Service Volume (SSV). In the second part of the talk, we will describe the Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) mission that aims to make the first in-space demonstration of X-ray pulsar navigation (XNAV). SEXTANT is attached to the NASA astrophysics mission Neutron-star Interior Composition ExploreR (NICER) whose International Space Station mounted X-ray telescope is investigating the fundamental physics of extremes in gravity, material density, and electromagnetic fields found in neutron stars, and whose instrument provides a nearly ideal navigation sensor for XNAV.

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.

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

... Devices, Navigation and Display Systems, Radar Systems, Navigational Aids, Mapping Systems and Related... navigation products, including GPS devices, navigation and display systems, radar systems, navigational aids..., radar systems, navigational aids, mapping systems and related software by reason of infringement of one...

Navigable networks as Nash equilibria of navigation games

PubMed Central

Gulyás, András; Bíró, József J.; Kőrösi, Attila; Rétvári, Gábor; Krioukov, Dmitri

2015-01-01

Common sense suggests that networks are not random mazes of purposeless connections, but that these connections are organized so that networks can perform their functions well. One function common to many networks is targeted transport or navigation. Here, using game theory, we show that minimalistic networks designed to maximize the navigation efficiency at minimal cost share basic structural properties with real networks. These idealistic networks are Nash equilibria of a network construction game whose purpose is to find an optimal trade-off between the network cost and navigability. We show that these skeletons are present in the Internet, metabolic, English word, US airport, Hungarian road networks, and in a structural network of the human brain. The knowledge of these skeletons allows one to identify the minimal number of edges, by altering which one can efficiently improve or paralyse navigation in the network. PMID:26138277

Hierarchical State-Space Estimation of Leatherback Turtle Navigation Ability

PubMed Central

Mills Flemming, Joanna; Jonsen, Ian D.; Field, Christopher A.

2010-01-01

Remotely sensed tracking technology has revealed remarkable migration patterns that were previously unknown; however, models to optimally use such data have developed more slowly. Here, we present a hierarchical Bayes state-space framework that allows us to combine tracking data from a collection of animals and make inferences at both individual and broader levels. We formulate models that allow the navigation ability of animals to be estimated and demonstrate how information can be combined over many animals to allow improved estimation. We also show how formal hypothesis testing regarding navigation ability can easily be accomplished in this framework. Using Argos satellite tracking data from 14 leatherback turtles, 7 males and 7 females, during their southward migration from Nova Scotia, Canada, we find that the circle of confusion (the radius around an animal's location within which it is unable to determine its location precisely) is approximately 96 km. This estimate suggests that the turtles' navigation does not need to be highly accurate, especially if they are able to use more reliable cues as they near their destination. Moreover, for the 14 turtles examined, there is little evidence to suggest that male and female navigation abilities differ. Because of the minimal assumptions made about the movement process, our approach can be used to estimate and compare navigation ability for many migratory species that are able to carry electronic tracking devices. PMID:21203382

Diver-based integrated navigation/sonar sensor

NASA Astrophysics Data System (ADS)

Lent, Keith H.

1999-07-01

Two diver based systems, the Small Object Locating Sonar (SOLS) and the Integrated Navigation and Sonar Sensor (INSS) have been developed at Applied Research Laboratories, the University of Texas at Austin (ARL:UT). They are small and easy to use systems that allow a diver to: detect, classify, and identify underwater objects; render large sector visual images; and track, map and reacquire diver location, diver path, and target locations. The INSS hardware consists of a unique, simple, single beam high resolution sonar, an acoustic navigation systems, an electronic depth gauge, compass, and GPS and RF interfaces, all integrated with a standard 486 based PC. These diver sonars have been evaluated by the very shallow water mine countermeasure detachment since spring 1997. Results are very positive, showing significantly greater capabilities than current diver held systems. For example, the detection ranges are increased over existing systems, and the system allows the divers to classify mines at a significant stand off range. As a result, the INSS design has been chosen for acquisition as the next generation diver navigation and sonar system. The EDMs for this system will be designed and built by ARL:UT during 1998 and 1999 with production planned in 2000.

Patient Navigation from the Paired Perspectives of Cancer Patients and Navigators: A Qualitative Analysis

PubMed Central

Yosha, Amanat M.; Carroll, Jennifer K.; Hendren, Samantha; Salamone, Charcy M.; Sanders, Mechelle; Fiscella, Kevin; Epstein, Ronald M.

2011-01-01

Objective Patient navigation for cancer care assesses and alleviates barriers to health care services. We examined paired perspectives of cancer patients and their navigators to examine the process of patient navigation. We explored the strengths, limitations, and our own lessons learned about adopting the novel methodology of multiperspective analysis. Methods As part of a larger RCT, patients and navigators were interviewed separately. We reviewed interviews with 18 patient-navigator dyads. Dyad summaries were created that explicitly incorporated both patient and navigator perspectives. Emerging themes and verbatim quotations were reflected in the summaries. Results Paired perspectives were valuable in identifying struggles that arose during navigation. These were represented as imbalanced investment and relational amelioration. Patients and navigators had general consensus about important patient needs for cancer care, but characterized these needs differently. Conclusion Our experience with multiperspective analysis revealed a methodology that delivers novel relational findings, but is best conducted de novo rather than as part of a larger study. Practice Implications Multiperspective analysis should be more widely adopted with clear aims and analytic strategy that strengthen the ability to reveal relational dynamics. Navigation training programs should anticipate navigator struggles and provide navigators with tools to manage them. PMID:21255958

GPS/MEMS IMU/Microprocessor Board for Navigation

NASA Technical Reports Server (NTRS)

Gender, Thomas K.; Chow, James; Ott, William E.

2009-01-01

A miniaturized instrumentation package comprising a (1) Global Positioning System (GPS) receiver, (2) an inertial measurement unit (IMU) consisting largely of surface-micromachined sensors of the microelectromechanical systems (MEMS) type, and (3) a microprocessor, all residing on a single circuit board, is part of the navigation system of a compact robotic spacecraft intended to be released from a larger spacecraft [e.g., the International Space Station (ISS)] for exterior visual inspection of the larger spacecraft. Variants of the package may also be useful in terrestrial collision-detection and -avoidance applications. The navigation solution obtained by integrating the IMU outputs is fed back to a correlator in the GPS receiver to aid in tracking GPS signals. The raw GPS and IMU data are blended in a Kalman filter to obtain an optimal navigation solution, which can be supplemented by range and velocity data obtained by use of (l) a stereoscopic pair of electronic cameras aboard the robotic spacecraft and/or (2) a laser dynamic range imager aboard the ISS. The novelty of the package lies mostly in those aspects of the design of the MEMS IMU that pertain to controlling mechanical resonances and stabilizing scale factors and biases.

Implementation and Impact of Patient Lay Navigator-Led Advance Care Planning Conversations.

PubMed

Rocque, Gabrielle B; Dionne-Odom, J Nicholas; Sylvia Huang, Chao-Hui; Niranjan, Soumya J; Williams, Courtney P; Jackson, Bradford E; Halilova, Karina I; Kenzik, Kelly M; Bevis, Kerri S; Wallace, Audrey S; Lisovicz, Nedra; Taylor, Richard A; Pisu, Maria; Partridge, Edward E; Butler, Thomas W; Briggs, Linda A; Kvale, Elizabeth A

2017-04-01

Advance care planning (ACP) improves alignment between patient preferences for life-sustaining treatment and care received at end of life (EOL). To evaluate implementation of lay navigator-led ACP. A convergent, parallel mixed-methods design was used to evaluate implementation of navigator-led ACP across 12 cancer centers. Data collection included 1) electronic navigation records, 2) navigator surveys (n = 45), 3) claims-based patient outcomes (n = 820), and 4) semistructured navigator interviews (n = 26). Outcomes of interest included 1) the number of ACP conversations completed, 2) navigator self-efficacy, 3) patient resource utilization, hospice use, and chemotherapy at EOL, and 4) navigator-perceived barriers and facilitators to ACP. From June 1, 2014 to December 31, 2015, 50 navigators completed Respecting Choices ® First Steps ACP Facilitator training. Navigators approached 18% of patients (1319/8704); 481 completed; 472 in process; 366 declined. Navigators were more likely to approach African American patients than Caucasian patients (20% vs. 14%, P < 0.001). Significant increases in ACP self-efficacy were observed after training. The mean score for feeling prepared to conduct ACP conversations increased from 5.6/10 to 7.5/10 (P < 0.001). In comparison with patients declining ACP participation (n = 171), decedents in their final 30 days of life who engaged in ACP (n = 437) had fewer hospitalizations (46% vs. 56%, P = 0.02). Key facilitators of successful implementation included physician buy-in, patient readiness, and prior ACP experience; barriers included space limitations, identifying the "right" time to start conversations, and personal discomfort discussing EOL. A navigator-led ACP program was feasible and may be associated with lower rates of resource utilization near EOL. Copyright © 2017 American Academy of Hospice and Palliative Medicine. All rights reserved.

The Aging Navigational System.

PubMed

Lester, Adam W; Moffat, Scott D; Wiener, Jan M; Barnes, Carol A; Wolbers, Thomas

2017-08-30

The discovery of neuronal systems dedicated to computing spatial information, composed of functionally distinct cell types such as place and grid cells, combined with an extensive body of human-based behavioral and neuroimaging research has provided us with a detailed understanding of the brain's navigation circuit. In this review, we discuss emerging evidence from rodents, non-human primates, and humans that demonstrates how cognitive aging affects the navigational computations supported by these systems. Critically, we show 1) that navigational deficits cannot solely be explained by general deficits in learning and memory, 2) that there is no uniform decline across different navigational computations, and 3) that navigational deficits might be sensitive markers for impending pathological decline. Following an introduction to the mechanisms underlying spatial navigation and how they relate to general processes of learning and memory, the review discusses how aging affects the perception and integration of spatial information, the creation and storage of memory traces for spatial information, and the use of spatial information during navigational behavior. The closing section highlights the clinical potential of behavioral and neural markers of spatial navigation, with a particular emphasis on neurodegenerative disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

A greedy-navigator approach to navigable city plans

NASA Astrophysics Data System (ADS)

Lee, Sang Hoon; Holme, Petter

2013-01-01

We use a set of four theoretical navigability indices for street maps to investigate the shape of the resulting street networks, if they are grown by optimizing these indices. The indices compare the performance of simulated navigators (having a partial information about the surroundings, like humans in many real situations) to the performance of optimally navigating individuals. We show that our simple greedy shortcut construction strategy generates the emerging structures that are different from real road network, but not inconceivable. The resulting city plans, for all navigation indices, share common qualitative properties such as the tendency for triangular blocks to appear, while the more quantitative features, such as degree distributions and clustering, are characteristically different depending on the type of metrics and routing strategies. We show that it is the type of metrics used which determines the overall shapes characterized by structural heterogeneity, but the routing schemes contribute to more subtle details of locality, which is more emphasized in case of unrestricted connections when the edge crossing is allowed.

Dermatology and pathology arrangements: navigating the compliance risks.

PubMed

Wood, Jane Pine; Cougevan, Bridget; McGovern, Jenny

2013-12-01

Purchased service arrangements, establishing in-house professional pathology services, conducting technical component histology within a dermatology practice, and electronic medical records technology donations are ways that dermatology practices are responding to the current health care delivery and payment changes. This article will provide a general framework for navigating the compliance risks and structure considerations associated with these relationships between dermatologists and pathologists.

Navigational Guidance and Ablation Planning Tools for Interventional Radiology.

PubMed

Sánchez, Yadiel; Anvari, Arash; Samir, Anthony E; Arellano, Ronald S; Prabhakar, Anand M; Uppot, Raul N

Image-guided biopsy and ablation relies on successful identification and targeting of lesions. Currently, image-guided procedures are routinely performed under ultrasound, fluoroscopy, magnetic resonance imaging, or computed tomography (CT) guidance. However, these modalities have their limitations including inadequate visibility of the lesion, lesion or organ or patient motion, compatibility of instruments in an magnetic resonance imaging field, and, for CT and fluoroscopy cases, radiation exposure. Recent advances in technology have resulted in the development of a new generation of navigational guidance tools that can aid in targeting lesions for biopsy or ablations. These navigational guidance tools have evolved from simple hand-held trajectory guidance tools, to electronic needle visualization, to image fusion, to the development of a body global positioning system, to growth in cone-beam CT, and to ablation volume planning. These navigational systems are promising technologies that not only have the potential to improve lesion targeting (thereby increasing diagnostic yield of a biopsy or increasing success of tumor ablation) but also have the potential to decrease radiation exposure to the patient and staff, decrease procedure time, decrease the sedation requirements, and improve patient safety. The purpose of this article is to describe the challenges in current standard image-guided techniques, provide a definition and overview for these next-generation navigational devices, and describe the current limitations of these, still evolving, next-generation navigational guidance tools. Copyright © 2017 Elsevier Inc. All rights reserved.

The anatomy of a World Wide Web library service: the BONES demonstration project. Biomedically Oriented Navigator of Electronic Services.

PubMed Central

Schnell, E H

1995-01-01

In 1994, the John A. Prior Health Sciences Library at Ohio State University began to develop a World Wide Web demonstration project, the Biomedically Oriented Navigator of Electronic Services (BONES). The initial intent of BONES was to facilitate the health professional's access to Internet resources by organizing them in a systematic manner. The project not only met this goal but also helped identify the resources needed to launch a full-scale Web library service. This paper discusses the tasks performed and resources used in the development of BONES and describes the creation and organization of documents on the BONES Web server. The paper also discusses the outcomes of the project and the impact on the library's staff and services. PMID:8547903

Relative Navigation for Formation Flying of Spacecraft

NASA Technical Reports Server (NTRS)

Alonso, Roberto; Du, Ju-Young; Hughes, Declan; Junkins, John L.; Crassidis, John L.

2001-01-01

This paper presents a robust and efficient approach for relative navigation and attitude estimation of spacecraft flying in formation. This approach uses measurements from a new optical sensor that provides a line of sight vector from the master spacecraft to the secondary satellite. The overall system provides a novel, reliable, and autonomous relative navigation and attitude determination system, employing relatively simple electronic circuits with modest digital signal processing requirements and is fully independent of any external systems. Experimental calibration results are presented, which are used to achieve accurate line of sight measurements. State estimation for formation flying is achieved through an optimal observer design. Also, because the rotational and translational motions are coupled through the observation vectors, three approaches are suggested to separate both signals just for stability analysis. Simulation and experimental results indicate that the combined sensor/estimator approach provides accurate relative position and attitude estimates.

Taux: A System for Evaluating Sound Feedback in Navigational Tasks

ERIC Educational Resources Information Center

Lutz, Robert J.

2008-01-01

This thesis presents the design and development of an evaluation system for generating audio displays that provide feedback to persons performing navigation tasks. It first develops the need for such a system by describing existing wayfinding solutions, investigating new electronic location-based methods that have the potential of changing these…

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.

Coordinating sensing and local navigation

NASA Technical Reports Server (NTRS)

Slack, Marc G.

1991-01-01

Based on Navigation Templates (or NaTs), this work presents a new paradigm for local navigation which addresses the noisy and uncertain nature of sensor data. Rather than creating a new navigation plan each time the robot's perception of the world changes, the technique incorporates perceptual changes directly into the existing navigation plan. In this way, the robot's navigation plan is quickly and continuously modified, resulting in actions that remain coordinated with its changing perception of the world.

Daytime Celestial Navigation for the Novice

NASA Astrophysics Data System (ADS)

Sadler, Philip M.; Night, Christopher

2010-03-01

What kinds of astronomical lab activities can high school and college astronomy students carry out easily in daytime? The most impressive is the determination of latitude and longitude from observations of the Sun. The ``shooting of a noon sight'' and its ``reduction to a position'' grew to become a daily practice at the start of the 19th century1 following the perfection of the marine chronometer by John Harrison and its mass production.2 This technique is still practiced by navigators in this age of GPS. Indeed, the U.S. Coast Guard exams for ocean-going licenses include celestial navigation.3 These techniques continue to be used by the military and by private sailors as a backup to all-too-fallible and jammable electronic navigation systems. A sextant, a nautical almanac,4 special sight reduction tables,5 and involved calculations are needed to determine position to the nearest mile using the Sun, Moon, stars, or planets. Yet, finding latitude and longitude to better than 30 miles from measurements of the Sun's altitude is easily within the capability of those taking astronomy or physics for the first time by applying certain basic principles. Moreover, it shows a practical application of astronomy in use the world over. The streamlined method described here takes advantage of the similar level of accuracy of its three components: 1.Observations using a homemade quadrant6 (instead of a sextant), 2. Student-made graphs of the altitude of the Sun over a day7 (replacing lengthy calculation using sight reduction tables), and 3. An averaged 20-year analemma used to find the Sun's navigational coordinates8,9 (rather than the 300+ page Nautical Almanac updated yearly).

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

... Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE...), will report the channel conditions promptly, using standard tabular forms, to: Director, Defense... operations in important channels in tidal waters—either in progress and not already reported, or soon to be...

Preliminary navigation accuracy analysis for the TDRSS Onboard Navigation System (TONS) experiment on EP/EUVE

NASA Technical Reports Server (NTRS)

Gramling, C. J.; Long, A. C.; Lee, T.; Ottenstein, N. A.; Samii, M. V.

1991-01-01

A Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (TONS) is currently being developed by NASA to provide a high accuracy autonomous navigation capability for users of TDRSS and its successor, the Advanced TDRSS (ATDRSS). The fully autonomous user onboard navigation system will support orbit determination, time determination, and frequency determination, based on observation of a continuously available, unscheduled navigation beacon signal. A TONS experiment will be performed in conjunction with the Explorer Platform (EP) Extreme Ultraviolet Explorer (EUVE) mission to flight quality TONS Block 1. An overview is presented of TONS and a preliminary analysis of the navigation accuracy anticipated for the TONS experiment. Descriptions of the TONS experiment and the associated navigation objectives, as well as a description of the onboard navigation algorithms, are provided. The accuracy of the selected algorithms is evaluated based on the processing of realistic simulated TDRSS one way forward link Doppler measurements. The analysis process is discussed and the associated navigation accuracy results are presented.

Impact of Patient Navigation on Timely Cancer Care: The Patient Navigation Research Program

PubMed Central

Battaglia, Tracy A.; Calhoun, Elizabeth; Darnell, Julie S.; Dudley, Donald J.; Fiscella, Kevin; Hare, Martha L.; LaVerda, Nancy; Lee, Ji-Hyun; Levine, Paul; Murray, David M.; Patierno, Steven R.; Raich, Peter C.; Roetzheim, Richard G.; Simon, Melissa; Snyder, Frederick R.; Warren-Mears, Victoria; Whitley, Elizabeth M.; Winters, Paul; Young, Gregory S.; Paskett, Electra D.

2014-01-01

Background Patient navigation is a promising intervention to address cancer disparities but requires a multisite controlled trial to assess its effectiveness. Methods The Patient Navigation Research Program compared patient navigation with usual care on time to diagnosis or treatment for participants with breast, cervical, colorectal, or prostate screening abnormalities and/or cancers between 2007 and 2010. Patient navigators developed individualized strategies to address barriers to care, with the focus on preventing delays in care. To assess timeliness of diagnostic resolution, we conducted a meta-analysis of center- and cancer-specific adjusted hazard ratios (aHRs) comparing patient navigation vs usual care. To assess initiation of cancer therapy, we calculated a single aHR, pooling data across all centers and cancer types. We conducted a metaregression to evaluate variability across centers. All statistical tests were two-sided. Results The 10521 participants with abnormal screening tests and 2105 with a cancer or precancer diagnosis were predominantly from racial/ethnic minority groups (73%) and publically insured (40%) or uninsured (31%). There was no benefit during the first 90 days of care, but a benefit of navigation was seen from 91 to 365 days for both diagnostic resolution (aHR = 1.51; 95% confidence interval [CI] = 1.23 to 1.84; P < .001)) and treatment initiation (aHR = 1.43; 95% CI = 1.10 to 1.86; P < .007). Metaregression revealed that navigation had its greatest benefits within centers with the greatest delays in follow-up under usual care. Conclusions Patient navigation demonstrated a moderate benefit in improving timely cancer care. These results support adoption of patient navigation in settings that serve populations at risk of being lost to follow-up. PMID:24938303

A Leapfrog Navigation System

NASA Astrophysics Data System (ADS)

Opshaug, Guttorm Ringstad

There are times and places where conventional navigation systems, such as the Global Positioning System (GPS), are unavailable due to anything from temporary signal occultations to lack of navigation system infrastructure altogether. The goal of the Leapfrog Navigation System (LNS) is to provide localized positioning services for such cases. The concept behind leapfrog navigation is to advance a group of navigation units teamwise into an area of interest. In a practical 2-D case, leapfrogging assumes known initial positions of at least two currently stationary navigation units. Two or more mobile units can then start to advance into the area of interest. The positions of the mobiles are constantly being calculated based on cross-range distance measurements to the stationary units, as well as cross-ranges among the mobiles themselves. At some point the mobile units stop, and the stationary units are released to move. This second team of units (now mobile) can then overtake the first team (now stationary) and travel even further towards the common goal of the group. Since there always is one stationary team, the position of any unit can be referenced back to the initial positions. Thus, LNS provides absolute positioning. I developed navigation algorithms needed to solve leapfrog positions based on cross-range measurements. I used statistical tools to predict how position errors would grow as a function of navigation unit geometry, cross-range measurement accuracy and previous position errors. Using this knowledge I predicted that a 4-unit Leapfrog Navigation System using 100 m baselines and 200 m leap distances could travel almost 15 km before accumulating absolute position errors of 10 m (1sigma). Finally, I built a prototype leapfrog navigation system using 4 GPS transceiver ranging units. I placed the 4 units in the vertices a 10m x 10m square, and leapfrogged the group 20 meters forwards, and then back again (40 m total travel). Average horizontal RMS position

Terrain matching image pre-process and its format transform in autonomous underwater navigation

NASA Astrophysics Data System (ADS)

Cao, Xuejun; Zhang, Feizhou; Yang, Dongkai; Yang, Bogang

2007-06-01

Underwater passive navigation technology is one of the important development orientations in the field of modern navigation. With the advantage of high self-determination, stealth at sea, anti-jamming and high precision, passive navigation is completely meet with actual navigation requirements. Therefore passive navigation has become a specific navigating method for underwater vehicles. The scientists and researchers in the navigating field paid more attention to it. The underwater passive navigation can provide accurate navigation information with main Inertial Navigation System (INS) for a long period, such as location and speed. Along with the development of micro-electronics technology, the navigation of AUV is given priority to INS assisted with other navigation methods, such as terrain matching navigation. It can provide navigation ability for a long period, correct the errors of INS and make AUV not emerge from the seabed termly. With terrain matching navigation technique, in the assistance of digital charts and ocean geographical characteristics sensors, we carry through underwater image matching assistant navigation to obtain the higher location precision, therefore it is content with the requirement of underwater, long-term, high precision and all-weather of the navigation system for Autonomous Underwater Vehicles. Tertian-assistant navigation (TAN) is directly dependent on the image information (map information) in the navigating field to assist the primary navigation system according to the path appointed in advance. In TAN, a factor coordinative important with the system operation is precision and practicability of the storable images and the database which produce the image data. If the data used for characteristics are not suitable, the system navigation precision will be low. Comparing with terrain matching assistant navigation system, image matching navigation system is a kind of high precision and low cost assistant navigation system, and its

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.

Optimal motion planning using navigation measure

NASA Astrophysics Data System (ADS)

Vaidya, Umesh

2018-05-01

We introduce navigation measure as a new tool to solve the motion planning problem in the presence of static obstacles. Existence of navigation measure guarantees collision-free convergence at the final destination set beginning with almost every initial condition with respect to the Lebesgue measure. Navigation measure can be viewed as a dual to the navigation function. While the navigation function has its minimum at the final destination set and peaks at the obstacle set, navigation measure takes the maximum value at the destination set and is zero at the obstacle set. A linear programming formalism is proposed for the construction of navigation measure. Set-oriented numerical methods are utilised to obtain finite dimensional approximation of this navigation measure. Application of the proposed navigation measure-based theoretical and computational framework is demonstrated for a motion planning problem in a complex fluid flow.

A navigation system for the visually impaired using colored navigation lines and RFID tags.

PubMed

Seto, First Tatsuya

2009-01-01

In this paper, we describe about a developed navigation system that supports the independent walking of the visually impaired in the indoor space. Our developed instrument consists of a navigation system and a map information system. These systems are installed on a white cane. Our navigation system can follow a colored navigation line that is set on the floor. In this system, a color sensor installed on the tip of a white cane senses the colored navigation line, and the system informs the visually impaired that he/she is walking along the navigation line by vibration. The color recognition system is controlled by a one-chip microprocessor and this system can discriminate 6 colored navigation lines. RFID tags and a receiver for these tags are used in the map information system. The RFID tags and the RFID tag receiver are also installed on a white cane. The receiver receives tag information and notifies map information to the user by mp3 formatted pre-recorded voice. Three normal subjects who were blindfolded with an eye mask were tested with this system. All of them were able to walk along the navigation line. The performance of the map information system was good. Therefore, our system will be extremely valuable in supporting the activities of the visually impaired.

Tactile-Foot Stimulation Can Assist the Navigation of People with Visual Impairment

PubMed Central

Velázquez, Ramiro; Pissaloux, Edwige; Lay-Ekuakille, Aimé

2015-01-01

Background. Tactile interfaces that stimulate the plantar surface with vibrations could represent a step forward toward the development of wearable, inconspicuous, unobtrusive, and inexpensive assistive devices for people with visual impairments. Objective. To study how people understand information through their feet and to maximize the capabilities of tactile-foot perception for assisting human navigation. Methods. Based on the physiology of the plantar surface, three prototypes of electronic tactile interfaces for the foot have been developed. With important technological improvements between them, all three prototypes essentially consist of a set of vibrating actuators embedded in a foam shoe-insole. Perceptual experiments involving direction recognition and real-time navigation in space were conducted with a total of 60 voluntary subjects. Results. The developed prototypes demonstrated that they are capable of transmitting tactile information that is easy and fast to understand. Average direction recognition rates were 76%, 88.3%, and 94.2% for subjects wearing the first, second, and third prototype, respectively. Exhibiting significant advances in tactile-foot stimulation, the third prototype was evaluated in navigation tasks. Results show that subjects were capable of following directional instructions useful for navigating spaces. Conclusion. Footwear providing tactile stimulation can be considered for assisting the navigation of people with visual impairments. PMID:27019593

Tactile-Foot Stimulation Can Assist the Navigation of People with Visual Impairment.

PubMed

Velázquez, Ramiro; Pissaloux, Edwige; Lay-Ekuakille, Aimé

2015-01-01

Background. Tactile interfaces that stimulate the plantar surface with vibrations could represent a step forward toward the development of wearable, inconspicuous, unobtrusive, and inexpensive assistive devices for people with visual impairments. Objective. To study how people understand information through their feet and to maximize the capabilities of tactile-foot perception for assisting human navigation. Methods. Based on the physiology of the plantar surface, three prototypes of electronic tactile interfaces for the foot have been developed. With important technological improvements between them, all three prototypes essentially consist of a set of vibrating actuators embedded in a foam shoe-insole. Perceptual experiments involving direction recognition and real-time navigation in space were conducted with a total of 60 voluntary subjects. Results. The developed prototypes demonstrated that they are capable of transmitting tactile information that is easy and fast to understand. Average direction recognition rates were 76%, 88.3%, and 94.2% for subjects wearing the first, second, and third prototype, respectively. Exhibiting significant advances in tactile-foot stimulation, the third prototype was evaluated in navigation tasks. Results show that subjects were capable of following directional instructions useful for navigating spaces. Conclusion. Footwear providing tactile stimulation can be considered for assisting the navigation of people with visual impairments.

33 CFR 207.169 - Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; 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 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation. 207.169 Section 207.169 Navigation... REGULATIONS § 207.169 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and...

33 CFR 207.169 - Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; 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 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation. 207.169 Section 207.169 Navigation... REGULATIONS § 207.169 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and...

Impact of patient navigation on timely cancer care: the Patient Navigation Research Program.

PubMed

Freund, Karen M; Battaglia, Tracy A; Calhoun, Elizabeth; Darnell, Julie S; Dudley, Donald J; Fiscella, Kevin; Hare, Martha L; LaVerda, Nancy; Lee, Ji-Hyun; Levine, Paul; Murray, David M; Patierno, Steven R; Raich, Peter C; Roetzheim, Richard G; Simon, Melissa; Snyder, Frederick R; Warren-Mears, Victoria; Whitley, Elizabeth M; Winters, Paul; Young, Gregory S; Paskett, Electra D

2014-06-01

Patient navigation is a promising intervention to address cancer disparities but requires a multisite controlled trial to assess its effectiveness. The Patient Navigation Research Program compared patient navigation with usual care on time to diagnosis or treatment for participants with breast, cervical, colorectal, or prostate screening abnormalities and/or cancers between 2007 and 2010. Patient navigators developed individualized strategies to address barriers to care, with the focus on preventing delays in care. To assess timeliness of diagnostic resolution, we conducted a meta-analysis of center- and cancer-specific adjusted hazard ratios (aHRs) comparing patient navigation vs usual care. To assess initiation of cancer therapy, we calculated a single aHR, pooling data across all centers and cancer types. We conducted a metaregression to evaluate variability across centers. All statistical tests were two-sided. The 10521 participants with abnormal screening tests and 2105 with a cancer or precancer diagnosis were predominantly from racial/ethnic minority groups (73%) and publically insured (40%) or uninsured (31%). There was no benefit during the first 90 days of care, but a benefit of navigation was seen from 91 to 365 days for both diagnostic resolution (aHR = 1.51; 95% confidence interval [CI] = 1.23 to 1.84; P < .001)) and treatment initiation (aHR = 1.43; 95% CI = 1.10 to 1.86; P < .007). Metaregression revealed that navigation had its greatest benefits within centers with the greatest delays in follow-up under usual care. Patient navigation demonstrated a moderate benefit in improving timely cancer care. These results support adoption of patient navigation in settings that serve populations at risk of being lost to follow-up. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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.

Educational and Scientific Applications of the \\itTime Navigator}

NASA Astrophysics Data System (ADS)

Cole, M.; Snow, J. T.; Slatt, R. M.

2001-05-01

Several recent conferences have noted the need to focus on the evolving interface between research and education at all levels of science, mathematics, engineering, and technology education. This interface, which is a distinguishing feature of graduate education in the U.S., is increasingly in demand at the undergraduate and K-12 levels, particularly in the earth sciences. In this talk, we present a new database for earth systems science and will explore applications to K-12 and undergraduate education, as well as the scientific and graduate role. The University of Oklahoma, College of Geosciences is in the process of acquiring the \\itTime Navigator}, a multi-disciplinary, multimedia database, which will form the core asset of the Center for Earth Systems Science. The Center, whose mission is to further the understanding of the dynamic Earth within both the academic and the general public communities, will serve as a portal for research, information, and education for scientists and educators. \\itTime Navigator} was developed over a period of some twenty years by the noted British geoscience author, Ron Redfern, in connection with the recently published, \\itOrigins, the evolution of continents, oceans and life}, the third in a series of books for the educated layperson. Over the years \\itTime Navigator} has evolved into an interactive, multimedia database displaying much of the significant geological, paleontological, climatological, and tectonic events from the latest Proterozoic (750 MYA) through to the present. The focus is mainly on the Western Hemisphere and events associated with the coalescence and breakup of Pangea and the evolution of the earth into its present form. \\itOrigins} will be available as early as Fall 2001 as an interactive electronic book for the general, scientifically-literate public. While electronic books are unlikely to replace traditional print books, the format does allow non-linear exploration of content. We believe that the

Racial and Ethnic Differences in Patient Navigation: Results from the Patient Navigation Research Program

PubMed Central

Ko, Naomi Y; Snyder, Frederick R; Raich, Peter C; Paskett, Electra D.; Dudley, Donald; Lee, Ji-Hyun; Levine, Paul H.; Freund, Karen M

2016-01-01

Purpose Patient navigation was developed to address barriers to timely care and reduce cancer disparities. This study explores navigation and racial and ethnic differences in time to diagnostic resolution of a cancer screening abnormality. Patients and Methods We conducted an analysis of the multi-site Patient Navigation Research Program. Participants with an abnormal cancer screening test were allocated to either navigation or control. Unadjusted median time to resolution was calculated for each racial and ethnic group by navigation and control. Multivariable Cox proportional hazards models were fit, adjusting for sex, age, cancer abnormality type, and health insurance, stratifying by center of care. Results Among a sample of 7,514 participants, 29% were Non-Hispanic White, 43% Hispanic, and 28% Black. In the control group Blacks had a longer median time to diagnostic resolution (108 days) than Non-Hispanic Whites (65 days) or Hispanics (68 days) (p< .0001). In the navigated groups, Blacks had a reduction in median time to diagnostic resolution (97 days) (p <.0001). In the multivariable models, among controls, Black race was associated with increased delay to diagnostic resolution (HR=0.77; 95% CI: 0.69, 0.84) compared to the Non-Hispanic Whites, which was reduced in the navigated arm (HR=0.85; 95% CI: 0.77, 0.94). Conclusion Patient navigation had its greatest impact for Black patients who had the greatest delays in care. PMID:27227342

Texas ports and navigation districts : overview.

DOT National Transportation Integrated Search

2017-01-01

The first Navigation District was established in 1909, and there are now 24 Navigation Districts statewide.1 Navigation districts generally provide for the construction and improvement of waterways in Texas for the purpose of navigation. The creation...

Characteristics of Effective Colorectal Cancer Screening Navigation Programs in Federally Qualified Health Centers: a Systematic Review

PubMed Central

Domingo, Jermy-Leigh B.; Braun, Kathryn L.

2017-01-01

In the U.S., colorectal cancer (CRC) incidence and mortality have declined due to screening and improvements in early detection; however, racial/ethnic disparities in screening and mortality persist. Patient navigation has been shown to be effective in increasing CRC screening prevalence. This systematic review answered three questions about navigation in federally qualified community health centers (FQHCs): 1) Which navigation activities increased CRC screening prevalence? 2) What were the challenges to implementing these programs in FQHCs? 3) Which clinic protocols supported screening completion? Findings suggest that navigation services must be tailored to the specific screening test provided. Federally qualified community health centers report difficulty maintaining a current electronic medical records system and sustaining funding; they should establish excellent patient tracking systems (for follow-up and annual rescreening) and establish multiple protocols to facilitate screening completion. With the movement toward patient-centered care models, patient navigation will be integral to FQHCs and their clients. PMID:28238992

Shuttle unified navigation filter, revision 1

NASA Technical Reports Server (NTRS)

Muller, E. S., Jr.

1973-01-01

Equations designed to meet the navigation requirements of the separate shuttle mission phases are presented in a series of reports entitled, Space Shuttle GN and C Equation Document. The development of these equations is based on performance studies carried out for each particular mission phase. Although navigation equations have been documented separately for each mission phase, a single unified navigation filter design is embodied in these separate designs. The purpose of this document is to present the shuttle navigation equations in a form in which they would most likely be coded-as the single unified navigation filter used in each mission phase. This document will then serve as a single general reference for the navigation equations replacing each of the individual mission phase navigation documents (which may still be used as a description of a particular navigation phase).

Electron content of the ionosphere and the plasma sphere on the basis of ATS-6-Data, NNSS-data, and ionograms. [Navy Navigation Satellite System

NASA Technical Reports Server (NTRS)

Leitinger, R.; Hartmann, G. K.; Davies, K.

1976-01-01

The reported investigation takes into account data obtained with the aid of the geostationary satellite ATS-6, the satellites of the U.S. navy navigation system (NNSS) at an altitude between 900 and 1200 km, and the satellites ISIS 1 and ISIS 2. The altitude range between ground and ATS-6 is divided into two regions, including the 'ionosphere', involving the region with an upper limit of 2000 km, and the 'plasma sphere', involving the region above an altitude of 2000 km. Data concerning the electron content obtained from different sources are compared, taking into account discrepancies between ionogram-derived values and values computed on the basis of satellite measurements. Attention is also given to the vertical electron content of the ionosphere on the basis of a combination of data obtained with the aid of the ATS-6 and the NNSS.

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).

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.

Electromagnetic navigation reduces surgical time and radiation exposure for proximal interlocking in retrograde femoral nailing.

PubMed

Somerson, Jeremy S; Rowley, David; Kennedy, Chad; Buttacavoli, Frank; Agarwal, Animesh

2014-07-01

To compare the time required for proximal locking screw placement between a standard freehand technique and the navigated technique, and to quantify the reduction in ionizing radiation exposure. A fresh frozen cadaver model was used for 48 proximal interlocking screw procedures. Each procedure consisted of insertion of 2 anteroposterior locking screws. Standard fluoroscopic technique was used for 24 procedures, and an electromagnetic navigation system was used for the remaining 24 procedures. Procedure duration was recorded using an electronic timer and radiation doses were documented. Mean total insertion time for both proximal interlocking screws was 405 ± 165.7 seconds with the freehand technique and 311 ± 78.3 seconds in the navigation group (P = 0.002). All procedures resulted in successful locking screw placement. Mean ionizing radiation exposure time for proximal locking was 29.5 ± 12.8 seconds. Proximal locking screw insertion using the navigation technique evaluated in this work was significantly faster than the standard fluoroscopic method. The navigated technique is effective and has the potential to prevent ionizing radiation exposure.

[Navigated retinal laser therapy].

PubMed

Kernt, M; Ulbig, M; Kampik, A; Neubauer, A S

2013-08-01

Navigated laser therapy introduces for the first time computerized assistance systems for retinal laser therapy. The Navilas system offers high precision and safety and provides additional benefits regarding standardization of planning, execution, documentation and quality assurance. The current focus of clinical application for navigated laser therapy besides laser treatment after retinal vein occlusion and panretinal laser photocoagulation in proliferative diabetic retinopathy (PDR) is diabetic macular edema. Recent data indicate that combined initial anti-vascular endothelial growth factor (anti-VEGF) and navigated macular laser therapy allows achievement and maintenance of treatment success with a minimum number of interventions. Despite very promising results the current assessment of navigated laser therapy is still limited by the evidence available worldwide.

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 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 solid...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 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 solid...

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 solid...

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 solid...

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 solid...

Indoor navigation by image recognition

NASA Astrophysics Data System (ADS)

Choi, Io Teng; Leong, Chi Chong; Hong, Ka Wo; Pun, Chi-Man

2017-07-01

With the progress of smartphones hardware, it is simple on smartphone using image recognition technique such as face detection. In addition, indoor navigation system development is much slower than outdoor navigation system. Hence, this research proves a usage of image recognition technique for navigation in indoor environment. In this paper, we introduced an indoor navigation application that uses the indoor environment features to locate user's location and a route calculating algorithm to generate an appropriate path for user. The application is implemented on Android smartphone rather than iPhone. Yet, the application design can also be applied on iOS because the design is implemented without using special features only for Android. We found that digital navigation system provides better and clearer location information than paper map. Also, the indoor environment is ideal for Image recognition processing. Hence, the results motivate us to design an indoor navigation system using image recognition.

Analysis of safety reports involving area navigation and required navigation performance procedures.

DOT National Transportation Integrated Search

2010-11-03

In order to achieve potential operational and safety benefits enabled by Area Navigation (RNAV) and Required Navigation Performance (RNP) procedures it is important to monitor emerging issues in their initial implementation. Reports from the Aviation...

Surface navigation on Mars with a Navigation Satellite

NASA Technical Reports Server (NTRS)

Vijayaraghavan, A.; Thurman, Sam W.; Kahn, Robert D.; Hastrup, Rolf C.

1992-01-01

Radiometric navigation data from the Deep Space Network (DSN) stations on the earth to transponders and other surface elements such as rovers and landers on Mars, can determine their positions to only within a kilometer in inertial space. The positional error is mostly in the z-component of the surface element parallel to the Martian spin-axis. However, with Doppler and differenced-Doppler data from a Navigation Satellite in orbit around Mars to two or more of such transponders on the planetary surface, their positions can be determined to within 15 meters (or 20 meters for one-way Doppler beacons on Mars) in inertial space. In this case, the transponders (or other vehicles) on Mars need not even be capable of directly communicating to the earth. When the Navigation Satellite data is complemented by radiometric observations from the DSN stations also, directly to the surface elements on Mars, their positions can be determined to within 3 meters in inertial space. The relative positions of such surface elements on Mars (relative to one another) in Mars-fixed coordinates, however, can be determined to within 5 meters from simply range and Doppler data from the DSN stations to the surface elements. These results are obtained from covariance studies assuming X-band data noise levels and data-arcs not exceeding 10 days. They are significant in the planning and deployment of a Mars-based navigation network necessary to support real-time operations during critical phases of manned exploration of Mars.

Surface navigation on Mars with a Navigation Satellite

NASA Astrophysics Data System (ADS)

Vijayaraghavan, A.; Thurman, Sam W.; Kahn, Robert D.; Hastrup, Rolf C.

Radiometric navigation data from the Deep Space Network (DSN) stations on the earth to transponders and other surface elements such as rovers and landers on Mars, can determine their positions to only within a kilometer in inertial space. The positional error is mostly in the z-component of the surface element parallel to the Martian spin-axis. However, with Doppler and differenced-Doppler data from a Navigation Satellite in orbit around Mars to two or more of such transponders on the planetary surface, their positions can be determined to within 15 meters (or 20 meters for one-way Doppler beacons on Mars) in inertial space. In this case, the transponders (or other vehicles) on Mars need not even be capable of directly communicating to the earth. When the Navigation Satellite data is complemented by radiometric observations from the DSN stations also, directly to the surface elements on Mars, their positions can be determined to within 3 meters in inertial space. The relative positions of such surface elements on Mars (relative to one another) in Mars-fixed coordinates, however, can be determined to within 5 meters from simply range and Doppler data from the DSN stations to the surface elements. These results are obtained from covariance studies assuming X-band data noise levels and data-arcs not exceeding 10 days. They are significant in the planning and deployment of a Mars-based navigation network necessary to support real-time operations during critical phases of manned exploration of Mars.

Computer-assisted navigation in orthopedic surgery.

PubMed

Mavrogenis, Andreas F; Savvidou, Olga D; Mimidis, George; Papanastasiou, John; Koulalis, Dimitrios; Demertzis, Nikolaos; Papagelopoulos, Panayiotis J

2013-08-01

Computer-assisted navigation has a role in some orthopedic procedures. It allows the surgeons to obtain real-time feedback and offers the potential to decrease intra-operative errors and optimize the surgical result. Computer-assisted navigation systems can be active or passive. Active navigation systems can either perform surgical tasks or prohibit the surgeon from moving past a predefined zone. Passive navigation systems provide intraoperative information, which is displayed on a monitor, but the surgeon is free to make any decisions he or she deems necessary. This article reviews the available types of computer-assisted navigation, summarizes the clinical applications and reviews the results of related series using navigation, and informs surgeons of the disadvantages and pitfalls of computer-assisted navigation in orthopedic surgery. Copyright 2013, SLACK Incorporated.

Bio-inspired polarized skylight navigation: a review

NASA Astrophysics Data System (ADS)

Zhang, Xi; Wan, Yongqin; Li, Lijing

2015-12-01

The idea of using skylight polarization in navigation is learned from animals such as desert ants and honeybees. Various research groups have been working on the development of novel navigation systems inspired by polarized skylight. The research of background in polarized skylight navigation is introduced, and basic principle of the insects navigation is expatiated. Then, the research progress status at home and abroad in skylight polarization pattern, three bio-inspired polarized skylight navigation sensors and polarized skylight navigation are reviewed. Finally, the research focuses in the field of polarized skylight navigation are analyzed. At the same time, the trend of development and prospect in the future are predicted. It is believed that the review is helpful to people understand polarized skylight navigation and polarized skylight navigation sensors.

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.

Navigating Space by the Stars

NASA Image and Video Library

2018-06-19

A tool that has helped guide sailors across oceans for centuries is now being tested aboard the International Space Station as a potential emergency navigation tool for guiding future spacecraft across the cosmos. The Sextant Navigation investigation tests use of a hand-held sextant aboard the space station. Sextants have a telescope-like optical sight to take precise angle measurements between pairs of stars from land or sea, enabling navigation without computer assistance. NASA’s Gemini missions conducted the first sextant sightings from a spacecraft, and designers built a sextant into Apollo vehicles as a navigation backup in the event the crew lost communications from their spacecraft. Jim Lovell demonstrated on Apollo 8 that sextant navigation could return a space vehicle home. Astronauts conducted additional sextant experiments on Skylab. Read more about the Sextant experiment happening aboard the space station: https://www.nasa.gov/mission_pages/station/research/news/Sextant_ISS HD Download: https://archive.org/details/jsc2018m000418_Navigating_Space_by_the_Stars

Space electronics technology summary

NASA Technical Reports Server (NTRS)

1976-01-01

An overview is given of current electronics R and D activities, potential future thrusts, and related NASA payoffs. Major increases in NASA mission return and significant concurrent reductions in mission cost appear possible through a focused, long range electronics technology program. The overview covers: guidance assessments, navigation and control, and sensing and data acquisition processing, storage, and transfer.

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.

46 CFR 183.420 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Navigation lights. 183.420 Section 183.420 Shipping...) ELECTRICAL INSTALLATION Lighting Systems § 183.420 Navigation lights. All vessels must have navigation lights..., except that a vessel of more than 19.8 meters (65 feet) in length must also have navigation lights that...

46 CFR 183.420 - Navigation lights.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Navigation lights. 183.420 Section 183.420 Shipping...) ELECTRICAL INSTALLATION Lighting Systems § 183.420 Navigation lights. All vessels must have navigation lights..., except that a vessel of more than 19.8 meters (65 feet) in length must also have navigation lights that...

46 CFR 183.420 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Navigation lights. 183.420 Section 183.420 Shipping...) ELECTRICAL INSTALLATION Lighting Systems § 183.420 Navigation lights. All vessels must have navigation lights..., except that a vessel of more than 19.8 meters (65 feet) in length must also have navigation lights that...

46 CFR 183.420 - Navigation lights.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Navigation lights. 183.420 Section 183.420 Shipping...) ELECTRICAL INSTALLATION Lighting Systems § 183.420 Navigation lights. All vessels must have navigation lights..., except that a vessel of more than 19.8 meters (65 feet) in length must also have navigation lights that...

46 CFR 183.420 - Navigation lights.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Navigation lights. 183.420 Section 183.420 Shipping...) ELECTRICAL INSTALLATION Lighting Systems § 183.420 Navigation lights. All vessels must have navigation lights..., except that a vessel of more than 19.8 meters (65 feet) in length must also have navigation lights that...

Mission Operations and Navigation Toolkit Environment

NASA Technical Reports Server (NTRS)

Sunseri, Richard F.; Wu, Hsi-Cheng; Hanna, Robert A.; Mossey, Michael P.; Duncan, Courtney B.; Evans, Scott E.; Evans, James R.; Drain, Theodore R.; Guevara, Michelle M.; Martin Mur, Tomas J.;

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

An excellent navigation system and experience in craniomaxillofacial navigation surgery: a double-center study

PubMed Central

Dai, Jiewen; Wu, Jinyang; Wang, Xudong; Yang, Xudong; Wu, Yunong; Xu, Bing; Shi, Jun; Yu, Hongbo; Cai, Min; Zhang, Wenbin; Zhang, Lei; Sun, Hao; Shen, Guofang; Zhang, Shilei

2016-01-01

Numerous problems regarding craniomaxillofacial navigation surgery are not well understood. In this study, we performed a double-center clinical study to quantitatively evaluate the characteristics of our navigation system and experience in craniomaxillofacial navigation surgery. Fifty-six patients with craniomaxillofacial disease were included and randomly divided into experimental (using our AccuNavi-A system) and control (using Strker system) groups to compare the surgical effects. The results revealed that the average pre-operative planning time was 32.32 mins vs 29.74 mins between the experimental and control group, respectively (p > 0.05). The average operative time was 295.61 mins vs 233.56 mins (p > 0.05). The point registration orientation accuracy was 0.83 mm vs 0.92 mm. The maximal average preoperative navigation orientation accuracy was 1.03 mm vs 1.17 mm. The maximal average persistent navigation orientation accuracy was 1.15 mm vs 0.09 mm. The maximal average navigation orientation accuracy after registration recovery was 1.15 mm vs 1.39 mm between the experimental and control group. All patients healed, and their function and profile improved. These findings demonstrate that although surgeons should consider the patients’ time and monetary costs, our qualified navigation surgery system and experience could offer an accurate guide during a variety of craniomaxillofacial surgeries. PMID:27305855

Integration of a synthetic vision system with airborne laser range scanner-based terrain referenced navigation for precision approach guidance

NASA Astrophysics Data System (ADS)

Uijt de Haag, Maarten; Campbell, Jacob; van Graas, Frank

2005-05-01

Synthetic Vision Systems (SVS) provide pilots with a virtual visual depiction of the external environment. When using SVS for aircraft precision approach guidance systems accurate positioning relative to the runway with a high level of integrity is required. Precision approach guidance systems in use today require ground-based electronic navigation components with at least one installation at each airport, and in many cases multiple installations to service approaches to all qualifying runways. A terrain-referenced approach guidance system is envisioned to provide precision guidance to an aircraft without the use of ground-based electronic navigation components installed at the airport. This autonomy makes it a good candidate for integration with an SVS. At the Ohio University Avionics Engineering Center (AEC), work has been underway in the development of such a terrain referenced navigation system. When used in conjunction with an Inertial Measurement Unit (IMU) and a high accuracy/resolution terrain database, this terrain referenced navigation system can provide navigation and guidance information to the pilot on a SVS or conventional instruments. The terrain referenced navigation system, under development at AEC, operates on similar principles as other terrain navigation systems: a ground sensing sensor (in this case an airborne laser scanner) gathers range measurements to the terrain; this data is then matched in some fashion with an onboard terrain database to find the most likely position solution and used to update an inertial sensor-based navigator. AEC's system design differs from today's common terrain navigators in its use of a high resolution terrain database (~1 meter post spacing) in conjunction with an airborne laser scanner which is capable of providing tens of thousands independent terrain elevation measurements per second with centimeter-level accuracies. When combined with data from an inertial navigator the high resolution terrain database and

46 CFR 120.420 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Navigation lights. 120.420 Section 120.420 Shipping... Systems § 120.420 Navigation lights. All vessels must have navigation lights that are in compliance with... than 19.8 meters (65 feet) in length must also have navigation lights that meet UL 1104, “Marine...

46 CFR 120.420 - Navigation lights.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Navigation lights. 120.420 Section 120.420 Shipping... Systems § 120.420 Navigation lights. All vessels must have navigation lights that are in compliance with... than 19.8 meters (65 feet) in length must also have navigation lights that meet UL 1104, “Marine...

46 CFR 120.420 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Navigation lights. 120.420 Section 120.420 Shipping... Systems § 120.420 Navigation lights. All vessels must have navigation lights that are in compliance with... than 19.8 meters (65 feet) in length must also have navigation lights that meet UL 1104, “Marine...

46 CFR 120.420 - Navigation lights.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Navigation lights. 120.420 Section 120.420 Shipping... Systems § 120.420 Navigation lights. All vessels must have navigation lights that are in compliance with... than 19.8 meters (65 feet) in length must also have navigation lights that meet UL 1104, “Marine...

46 CFR 120.420 - Navigation lights.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Navigation lights. 120.420 Section 120.420 Shipping... Systems § 120.420 Navigation lights. All vessels must have navigation lights that are in compliance with... than 19.8 meters (65 feet) in length must also have navigation lights that meet UL 1104, “Marine...

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) No...

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) No...

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) No...

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) No...

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) No...

The effects of age, spatial ability, and navigational information on navigational performance

DOT National Transportation Integrated Search

1995-12-01

The purpose of the study reported here was to examine whether age and spatial ability are factors that influence a driver?s ability to navigate and to use navigational displays. These factors were examined because previous research suggests that spat...

Autonomous Navigation Using Celestial Objects

NASA Technical Reports Server (NTRS)

Folta, David; Gramling, Cheryl; Leung, Dominic; Belur, Sheela; Long, Anne

1999-01-01

In the twenty-first century, National Aeronautics and Space Administration (NASA) Enterprises envision frequent low-cost missions to explore the solar system, observe the universe, and study our planet. Satellite autonomy is a key technology required to reduce satellite operating costs. The Guidance, Navigation, and Control Center (GNCC) at the Goddard Space Flight Center (GSFC) currently sponsors several initiatives associated with the development of advanced spacecraft systems to provide autonomous navigation and control. Autonomous navigation has the potential both to increase spacecraft navigation system performance and to reduce total mission cost. By eliminating the need for routine ground-based orbit determination and special tracking services, autonomous navigation can streamline spacecraft ground systems. Autonomous navigation products can be included in the science telemetry and forwarded directly to the scientific investigators. In addition, autonomous navigation products are available onboard to enable other autonomous capabilities, such as attitude control, maneuver planning and orbit control, and communications signal acquisition. Autonomous navigation is required to support advanced mission concepts such as satellite formation flying. GNCC has successfully developed high-accuracy autonomous navigation systems for near-Earth spacecraft using NASA's space and ground communications systems and the Global Positioning System (GPS). Recently, GNCC has expanded its autonomous navigation initiative to include satellite orbits that are beyond the regime in which use of GPS is possible. Currently, GNCC is assessing the feasibility of using standard spacecraft attitude sensors and communication components to provide autonomous navigation for missions including: libration point, gravity assist, high-Earth, and interplanetary orbits. The concept being evaluated uses a combination of star, Sun, and Earth sensor measurements along with forward-link Doppler

Basic Navigator Battery: An Experimental Selection Composite for Undergraduate Navigator Training.

ERIC Educational Resources Information Center

Shanahan, Frank M.; Kantor, Jeffrey E.

High rates of attrition among students in Undergraduate Navigator Training (UNT) is a major concern for Air Training Command. The main objective of this research was to evaluate the Basic Navigator Battery (BNB), a multi-test experimental selection instrument, for its potential to increase the validity of the Air Force Officer Qualifying Test…

Navigation/Prop Software Suite

NASA Technical Reports Server (NTRS)

Bruchmiller, Tomas; Tran, Sanh; Lee, Mathew; Bucker, Scott; Bupane, Catherine; Bennett, Charles; Cantu, Sergio; Kwong, Ping; Propst, Carolyn

2012-01-01

Navigation (Nav)/Prop software is used to support shuttle mission analysis, production, and some operations tasks. The Nav/Prop suite containing configuration items (CIs) resides on IPS/Linux workstations. It features lifecycle documents, and data files used for shuttle navigation and propellant analysis for all flight segments. This suite also includes trajectory server, archive server, and RAT software residing on MCC/Linux workstations. Navigation/Prop represents tool versions established during or after IPS Equipment Rehost-3 or after the MCC Rehost.

Racial and ethnic differences in patient navigation: Results from the Patient Navigation Research Program.

PubMed

Ko, Naomi Y; Snyder, Frederick R; Raich, Peter C; Paskett, Electra D; Dudley, Donald J; Lee, Ji-Hyun; Levine, Paul H; Freund, Karen M

2016-09-01

Patient navigation was developed to address barriers to timely care and reduce cancer disparities. The current study explored navigation and racial and ethnic differences in time to the diagnostic resolution of a cancer screening abnormality. The authors conducted an analysis of the multisite Patient Navigation Research Program. Participants with an abnormal cancer screening test were allocated to either navigation or control. The unadjusted median time to resolution was calculated for each racial and ethnic group by navigation and control. Multivariable Cox proportional hazards models were fit, adjusting for sex, age, cancer abnormality type, and health insurance and stratifying by center of care. Among a sample of 7514 participants, 29% were non-Hispanic white, 43% were Hispanic, and 28% were black. In the control group, black individuals were found to have a longer median time to diagnostic resolution (108 days) compared with non-Hispanic white individuals (65 days) or Hispanic individuals (68 days) (P<.0001). In the navigated groups, black individuals had a reduction in the median time to diagnostic resolution (97 days) (P<.0001). In the multivariable models, among controls, black race was found to be associated with an increased delay to diagnostic resolution (hazard ratio, 0.77; 95% confidence interval, 0.69-0.84) compared with non-Hispanic white individuals, which was reduced in the navigated arm (hazard ratio, 0.85; 95% confidence interval, 0.77-0.94). Patient navigation appears to have the greatest impact among black patients, who had the greatest delays in care. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2715-2722. © 2016 American Cancer Society. © 2016 American Cancer Society.

Can patient navigation improve receipt of recommended breast cancer care? Evidence from the National Patient Navigation Research Program.

PubMed

Ko, Naomi Y; Darnell, Julie S; Calhoun, Elizabeth; Freund, Karen M; Wells, Kristin J; Shapiro, Charles L; Dudley, Donald J; Patierno, Steven R; Fiscella, Kevin; Raich, Peter; Battaglia, Tracy A

2014-09-01

Poor and underserved women face barriers in receiving timely and appropriate breast cancer care. Patient navigators help individuals overcome these barriers, but little is known about whether patient navigation improves quality of care. The purpose of this study is to examine whether navigated women with breast cancer are more likely to receive recommended standard breast cancer care. Women with breast cancer who participated in the national Patient Navigation Research Program were examined to determine whether the care they received included the following: initiation of antiestrogen therapy in patients with hormone receptor-positive breast cancer; initiation of postlumpectomy radiation therapy; and initiation of chemotherapy in women younger than age 70 years with triple-negative tumors more than 1 cm. This is a secondary analysis of a multicenter quasi-experimental study funded by the National Cancer Institute to evaluate patient navigation. Multiple logistic regression was performed to compare differences in receipt of care between navigated and non-navigated participants. Among participants eligible for antiestrogen therapy, navigated participants (n = 380) had a statistically significant higher likelihood of receiving antiestrogen therapy compared with non-navigated controls (n = 381; odds ratio [OR], 1.73; P = .004) in a multivariable analysis. Among the participants eligible for radiation therapy after lumpectomy, navigated participants (n = 255) were no more likely to receive radiation (OR, 1.42; P = .22) than control participants (n = 297). We demonstrate that navigated participants were more likely than non-navigated participants to receive antiestrogen therapy. Future studies are required to determine the full impact patient navigation may have on ensuring that vulnerable populations receive quality care. © 2014 by American Society of Clinical Oncology.

Can Patient Navigation Improve Receipt of Recommended Breast Cancer Care? Evidence From the National Patient Navigation Research Program

PubMed Central

Ko, Naomi Y.; Darnell, Julie S.; Calhoun, Elizabeth; Freund, Karen M.; Wells, Kristin J.; Shapiro, Charles L.; Dudley, Donald J.; Patierno, Steven R.; Fiscella, Kevin; Raich, Peter; Battaglia, Tracy A.

2014-01-01

Purpose Poor and underserved women face barriers in receiving timely and appropriate breast cancer care. Patient navigators help individuals overcome these barriers, but little is known about whether patient navigation improves quality of care. The purpose of this study is to examine whether navigated women with breast cancer are more likely to receive recommended standard breast cancer care. Patients and Methods Women with breast cancer who participated in the national Patient Navigation Research Program were examined to determine whether the care they received included the following: initiation of antiestrogen therapy in patients with hormone receptor–positive breast cancer; initiation of postlumpectomy radiation therapy; and initiation of chemotherapy in women younger than age 70 years with triple-negative tumors more than 1 cm. This is a secondary analysis of a multicenter quasi-experimental study funded by the National Cancer Institute to evaluate patient navigation. Multiple logistic regression was performed to compare differences in receipt of care between navigated and non-navigated participants. Results Among participants eligible for antiestrogen therapy, navigated participants (n = 380) had a statistically significant higher likelihood of receiving antiestrogen therapy compared with non-navigated controls (n = 381; odds ratio [OR], 1.73; P = .004) in a multivariable analysis. Among the participants eligible for radiation therapy after lumpectomy, navigated participants (n = 255) were no more likely to receive radiation (OR, 1.42; P = .22) than control participants (n = 297). Conclusion We demonstrate that navigated participants were more likely than non-navigated participants to receive antiestrogen therapy. Future studies are required to determine the full impact patient navigation may have on ensuring that vulnerable populations receive quality care. PMID:25071111

Switching from reaching to navigation: differential cognitive strategies for spatial memory in children and adults.

PubMed

Belmonti, Vittorio; Cioni, Giovanni; Berthoz, Alain

2015-07-01

Navigational and reaching spaces are known to involve different cognitive strategies and brain networks, whose development in humans is still debated. In fact, high-level spatial processing, including allocentric location encoding, is already available to very young children, but navigational strategies are not mature until late childhood. The Magic Carpet (MC) is a new electronic device translating the traditional Corsi Block-tapping Test (CBT) to navigational space. In this study, the MC and the CBT were used to assess spatial memory for navigation and for reaching, respectively. Our hypothesis was that school-age children would not treat MC stimuli as navigational paths, assimilating them to reaching sequences. Ninety-one healthy children aged 6 to 11 years and 18 adults were enrolled. Overall short-term memory performance (span) on both tests, effects of sequence geometry, and error patterns according to a new classification were studied. Span increased with age on both tests, but relatively more in navigational than in reaching space, particularly in males. Sequence geometry specifically influenced navigation, not reaching. The number of body rotations along the path affected MC performance in children more than in adults, and in women more than in men. Error patterns indicated that navigational sequences were increasingly retained as global paths across development, in contrast to separately stored reaching locations. A sequence of spatial locations can be coded as a navigational path only if a cognitive switch from a reaching mode to a navigation mode occurs. This implies the integration of egocentric and allocentric reference frames, of visual and idiothetic cues, and access to long-term memory. This switch is not yet fulfilled at school age due to immature executive functions. © 2014 John Wiley & Sons Ltd.

Investigation of new techniques for aircraft navigation using the omega navigation

NASA Technical Reports Server (NTRS)

Baxa, E. G., Jr.

1978-01-01

An OMEGA navigation receiver with a microprocessor as the computational component was investigated. A version of the INTEL 4004 microprocessor macroassembler suitable for use on the CDC-6600 system and development of a FORTRAN IV simulator program for the microprocessor was developed. Supporting studies included development and evaluation of navigation algorithms to generate relative position information from OMEGA VLF phase measurements. Simulation studies were used to evaluate assumptions made in developing a navigation equation in OMEGA Line of Position (LOP) coordinates. Included in the navigation algorithms was a procedure for calculating a position in latitude/longitude given an OMEGA LOP fix. Implementation of a digital phase locked loop (DPLL) was evaluated on the basic of phase response characteristics over a range of input phase variations. Included also is an analytical evaluation on the basis of error probability of an algorithm for automatic time synchronization of the receiver to the OMEGA broadcast format. The use of actual OMEGA phase data and published propagation prediction corrections to determine phase velocity estimates was discussed.

Navigation Operations for the Magnetospheric Multiscale Mission

NASA Technical Reports Server (NTRS)

Long, Anne; Farahmand, Mitra; Carpenter, Russell

2015-01-01

The Magnetospheric Multiscale (MMS) mission employs four identical spinning spacecraft flying in highly elliptical Earth orbits. These spacecraft will fly in a series of tetrahedral formations with separations of less than 10 km. MMS navigation operations use onboard navigation to satisfy the mission definitive orbit and time determination requirements and in addition to minimize operations cost and complexity. The onboard navigation subsystem consists of the Navigator GPS receiver with Goddard Enhanced Onboard Navigation System (GEONS) software, and an Ultra-Stable Oscillator. The four MMS spacecraft are operated from a single Mission Operations Center, which includes a Flight Dynamics Operations Area (FDOA) that supports MMS navigation operations, as well as maneuver planning, conjunction assessment and attitude ground operations. The System Manager component of the FDOA automates routine operations processes. The GEONS Ground Support System component of the FDOA provides the tools needed to support MMS navigation operations. This paper provides an overview of the MMS mission and associated navigation requirements and constraints and discusses MMS navigation operations and the associated MMS ground system components built to support navigation-related operations.

An assessment of patient navigator activities in breast cancer patient navigation programs using a nine-principle framework.

PubMed

Gunn, Christine M; Clark, Jack A; Battaglia, Tracy A; Freund, Karen M; Parker, Victoria A

2014-10-01

To determine how closely a published model of navigation reflects the practice of navigation in breast cancer patient navigation programs. Observational field notes describing patient navigator activities collected from 10 purposefully sampled, foundation-funded breast cancer navigation programs in 2008-2009. An exploratory study evaluated a model framework for patient navigation published by Harold Freeman by using an a priori coding scheme based on model domains. Field notes were compiled and coded. Inductive codes were added during analysis to characterize activities not included in the original model. Programs were consistent with individual-level principles representing tasks focused on individual patients. There was variation with respect to program-level principles that related to program organization and structure. Program characteristics such as the use of volunteer or clinical navigators were identified as contributors to patterns of model concordance. This research provides a framework for defining the navigator role as focused on eliminating barriers through the provision of individual-level interventions. The diversity observed at the program level in these programs was a reflection of implementation according to target population. Further guidance may be required to assist patient navigation programs to define and tailor goals and measurement to community needs. © Health Research and Educational Trust.

An Assessment of Patient Navigator Activities in Breast Cancer Patient Navigation Programs Using a Nine-Principle Framework

PubMed Central

Gunn, Christine M; Clark, Jack A; Battaglia, Tracy A; Freund, Karen M; Parker, Victoria A

2014-01-01

Objective To determine how closely a published model of navigation reflects the practice of navigation in breast cancer patient navigation programs. Data Source Observational field notes describing patient navigator activities collected from 10 purposefully sampled, foundation-funded breast cancer navigation programs in 2008–2009. Study Design An exploratory study evaluated a model framework for patient navigation published by Harold Freeman by using an a priori coding scheme based on model domains. Data Collection Field notes were compiled and coded. Inductive codes were added during analysis to characterize activities not included in the original model. Principal Findings Programs were consistent with individual-level principles representing tasks focused on individual patients. There was variation with respect to program-level principles that related to program organization and structure. Program characteristics such as the use of volunteer or clinical navigators were identified as contributors to patterns of model concordance. Conclusions This research provides a framework for defining the navigator role as focused on eliminating barriers through the provision of individual-level interventions. The diversity observed at the program level in these programs was a reflection of implementation according to target population. Further guidance may be required to assist patient navigation programs to define and tailor goals and measurement to community needs. PMID:24820445

Relative Navigation of Formation Flying Satellites

NASA Technical Reports Server (NTRS)

Long, Anne; Kelbel, David; Lee, Taesul; Leung, Dominic; Carpenter, Russell; Gramling, Cheryl; Bauer, Frank (Technical Monitor)

2002-01-01

The Guidance, Navigation, and Control Center (GNCC) at Goddard Space Flight Center (GSFC) has successfully developed high-accuracy autonomous satellite navigation systems using the National Aeronautics and Space Administration's (NASA's) space and ground communications systems and the Global Positioning System (GPS). In addition, an autonomous navigation system that uses celestial object sensor measurements is currently under development and has been successfully tested using real Sun and Earth horizon measurements.The GNCC has developed advanced spacecraft systems that provide autonomous navigation and control of formation flyers in near-Earth, high-Earth, and libration point orbits. To support this effort, the GNCC is assessing the relative navigation accuracy achievable for proposed formations using GPS, intersatellite crosslink, ground-to-satellite Doppler, and celestial object sensor measurements. This paper evaluates the performance of these relative navigation approaches for three proposed missions with two or more vehicles maintaining relatively tight formations. High-fidelity simulations were performed to quantify the absolute and relative navigation accuracy as a function of navigation algorithm and measurement type. Realistically-simulated measurements were processed using the extended Kalman filter implemented in the GPS Enhanced Inboard Navigation System (GEONS) flight software developed by GSFC GNCC. Solutions obtained by simultaneously estimating all satellites in the formation were compared with the results obtained using a simpler approach based on differencing independently estimated state vectors.

Patients' experiences with navigation for cancer care.

PubMed

Carroll, Jennifer K; Humiston, Sharon G; Meldrum, Sean C; Salamone, Charcy M; Jean-Pierre, Pascal; Epstein, Ronald M; Fiscella, Kevin

2010-08-01

We examined how navigation, defined as the assessment and alleviation of barriers to adequate health care, influences patients' perspectives on the quality of their cancer care. We conducted post-study patient interviews from a randomized controlled trial (usual care vs. patient navigation services) from cancer diagnosis through treatment completion. Patients were recruited from 11 primary care, hospital and community oncology practices in New York. We interviewed patients about their expectations and experience of patient navigation or, for non-navigated patients, other sources of assistance. Thirty-five patients newly diagnosed with breast or colorectal cancer. Valued aspects of navigation included emotional support, assistance with information needs and problem-solving, and logistical coordination of cancer care. Unmet cancer care needs expressed by patients randomized to usual care consisted of lack of assistance or support with childcare, household responsibilities, coordination of care, and emotional support. Cancer patients value navigation. Instrumental benefits were the most important expectations for navigation from navigated and non-navigated patients. Navigated patients received emotional support and assistance with information needs, problem-solving, and logistical aspects of cancer care coordination. Navigation services may help improve cancer care outcomes important to patients by addressing fragmented, confusing, uncoordinated, or inefficient care. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Patients' Experiences with Navigation for Cancer Care

PubMed Central

Carroll, Jennifer K.; Humiston, Sharon G.; Meldrum, Sean C.; Salamone, Charcy M.; Jean-Pierre, Pascal; Epstein, Ronald M.; Fiscella, Kevin

2010-01-01

Objective We examined how navigation, defined as the assessment and alleviation of barriers to adequate health care, influences patients' perspectives on the quality of their cancer care. Methods We conducted post-study patient interviews from a randomized controlled trial (usual care vs. patient navigation services) from cancer diagnosis through treatment completion. Patients were recruited from 11 primary care, hospital and community oncology practices in New York. We interviewed patients about their expectations and experience of patient navigation or, for non-navigated patients, other sources of assistance. Results Thirty-five patients newly diagnosed with breast or colorectal cancer. Valued aspects of navigation included emotional support, assistance with information needs and problem-solving, and logistical coordination of cancer care. Unmet cancer care needs expressed by patients randomized to usual care consisted of lack of assistance or support with childcare, household responsibilities, coordination of care, and emotional support. Conclusion Cancer patients value navigation. Instrumental benefits were the most important expectations for navigation from navigated and non-navigated patients. Navigated patients received emotional support and assistance with information needs, problem-solving, and logistical aspects of cancer care coordination. Practice Implications Navigation services may help improve cancer care outcomes important to patients by addressing fragmented, confusing, uncoordinated, or inefficient care. PMID:20006459

Gender Differences in Online Reading Engagement, Metacognitive Strategies, Navigation Skills and Reading Literacy

ERIC Educational Resources Information Center

Wu, J-Y.

2014-01-01

This study examined how knowledge of metacognitive strategies and navigation skills mediate the relationship between online reading activities and printed reading assessment (PRA) and electronic reading assessment (ERA) across 19 countries using the PISA (Programme for International Student Assessment) 2009 database. Participants were 34?104…

47 CFR 76.1201 - Rights of subscribers to use or attach navigation devices.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Rights of subscribers to use or attach... programming distributor shall prevent the connection or use of navigation devices to or with its multichannel video programming system, except in those circumstances where electronic or physical harm would be...

47 CFR 76.1201 - Rights of subscribers to use or attach navigation devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Rights of subscribers to use or attach... programming distributor shall prevent the connection or use of navigation devices to or with its multichannel video programming system, except in those circumstances where electronic or physical harm would be...

Linked Autonomous Interplanetary Satellite Orbit Navigation

NASA Technical Reports Server (NTRS)

Parker, Jeffrey S.; Anderson, Rodney L.; Born, George H.; Leonard, Jason M.; McGranaghan, Ryan M.; Fujimoto, Kohei

2013-01-01

A navigation technology known as LiAISON (Linked Autonomous Interplanetary Satellite Orbit Navigation) has been known to produce very impressive navigation results for scenarios involving two or more cooperative satellites near the Moon, such that at least one satellite must be in an orbit significantly perturbed by the Earth, such as a lunar halo orbit. The two (or more) satellites track each other using satellite-to-satellite range and/or range-rate measurements. These relative measurements yield absolute orbit navigation when one of the satellites is in a lunar halo orbit, or the like. The geometry between a lunar halo orbiter and a GEO satellite continuously changes, which dramatically improves the information content of a satellite-to-satellite tracking signal. The geometrical variations include significant out-of-plane shifts, as well as inplane shifts. Further, the GEO satellite is almost continuously in view of a lunar halo orbiter. High-fidelity simulations demonstrate that LiAISON technology improves the navigation of GEO orbiters by an order of magnitude, relative to standard ground tracking. If a GEO satellite is navigated using LiAISON- only tracking measurements, its position is typically known to better than 10 meters. If LiAISON measurements are combined with simple radiometric ground observations, then the satellite s position is typically known to better than 3 meters, which is substantially better than the current state of GEO navigation. There are two features of LiAISON that are novel and advantageous compared with conventional satellite navigation. First, ordinary satellite-to-satellite tracking data only provides relative navigation of each satellite. The novelty is the placement of one navigation satellite in an orbit that is significantly perturbed by both the Earth and the Moon. A navigation satellite can track other satellites elsewhere in the Earth-Moon system and acquire knowledge about both satellites absolute positions and velocities

Relative Navigation of Formation-Flying Satellites

NASA Technical Reports Server (NTRS)

Long, Anne; Kelbel, David; Lee, Taesul; Leung, Dominic; Carpenter, J. Russell; Grambling, Cheryl

2002-01-01

This paper compares autonomous relative navigation performance for formations in eccentric, medium and high-altitude Earth orbits using Global Positioning System (GPS) Standard Positioning Service (SPS), crosslink, and celestial object measurements. For close formations, the relative navigation accuracy is highly dependent on the magnitude of the uncorrelated measurement errors. A relative navigation position accuracy of better than 10 centimeters root-mean-square (RMS) can be achieved for medium-altitude formations that can continuously track at least one GPS signal. A relative navigation position accuracy of better than 15 meters RMS can be achieved for high-altitude formations that have sparse tracking of the GPS signals. The addition of crosslink measurements can significantly improve relative navigation accuracy for formations that use sparse GPS tracking or celestial object measurements for absolute navigation.

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.

Are breast cancer navigation programs cost-effective? Evidence from the Chicago Cancer Navigation Project.

PubMed

Markossian, Talar W; Calhoun, Elizabeth A

2011-01-01

One of the aims of the Chicago Cancer Navigation Project (CCNP) is to reduce the interval of time between abnormal breast cancer screening and definitive diagnosis in patients who are navigated as compared to usual care. In this article, we investigate the extent to which total costs of breast cancer navigation can be offset by survival benefits and savings in lifetime breast cancer-attributable costs. Data sources for the cost-effectiveness analysis include data from published literature, secondary data from the NCI's Surveillance Epidemiology and End Results (SEER) program, and primary data from the CCNP. If women enrolled in CCNP receive breast cancer diagnosis earlier by 6 months as compared to usual care, then navigation is borderline cost-effective for $95,625 per life-year saved. Results from sensitivity analyses suggest that the cost-effectiveness of navigation is sensitive to: the interval of time between screening and diagnosis, percent increase in number of women who receive cancer diagnosis and treatment, women's age, and the positive predictive value of a mammogram. In planning cost-effective navigation programs, special considerations should be made regarding the characteristics of the disease, program participants, and the initial screening test that determines program eligibility. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Navigating oceans and cultures: Polynesian and European navigation systems in the late eighteenth century

NASA Astrophysics Data System (ADS)

Walker, M.

2012-05-01

Significant differences in the rotation of the celestial dome between the tropical and temperate zones did not stop the peoples of either the tropical Pacific or temperate Europe from using geocentric astronomy to guide exploration of the oceans. Although the differences in the night sky contributed to differences between the Pacific Island and European systems for navigation at sea, the two navigation systems exhibit substantial similarities. Both systems define positions on the surface of the Earth using two coordinates that vary at right angles to each other and use stars, and to a lesser extent the sun, to determine directions. This essay explores similarities and differences in the use of geocentric astronomy for navigation at sea by the peoples of Polynesia and Europe in the late eighteenth century. Captain Cook's orders to discover the unknown southern continent after observing the transit of Venus combined with differences in language and culture to obscure the deeper similarities between the navigation systems used by Cook and the Polynesians. Although it was a further 200 years before anthropologists studied Pacific navigation, collaborations in voyaging with communities in Oceania demonstrated the effectiveness of Pacific navigation systems, revived interest in traditional voyaging in island communities around the Pacific, and potentially open the way for further collaborations in other areas.

46 CFR 130.320 - Electronic position-fixing device.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory for...

46 CFR 130.320 - Electronic position-fixing device.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory for...

46 CFR 130.320 - Electronic position-fixing device.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory for...

46 CFR 130.320 - Electronic position-fixing device.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory for...

46 CFR 130.320 - Electronic position-fixing device.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory for...

Multi-Flight-Phase GPS Navigation Filter Applications to Terrestrial Vehicle Navigation and Positioning

NASA Technical Reports Server (NTRS)

Park, Young W.; Montez, Moises N.

1994-01-01

A candidate onboard space navigation filter demonstrated excellent performance (less than 8 meter level RMS semi-major axis accuracy) in performing orbit determination of a low-Earth orbit Explorer satellite using single-frequency real GPS data. This performance is significantly better than predicted by other simulation studies using dual-frequency GPS data. The study results revealed the significance of two new modeling approaches evaluated in the work. One approach introduces a single-frequency ionospheric correction through pseudo-range and phase range averaging implementation. The other approach demonstrates a precise axis-dependent characterization of dynamic sample space uncertainty to compute a more accurate Kalman filter gain. Additionally, this navigation filter demonstrates a flexibility to accommodate both perturbational dynamic and observational biases required for multi-flight phase and inhomogeneous application environments. This paper reviews the potential application of these methods and the filter structure to terrestrial vehicle and positioning applications. Both the single-frequency ionospheric correction method and the axis-dependent state noise modeling approach offer valuable contributions in cost and accuracy improvements for terrestrial GPS receivers. With a modular design approach to either 'plug-in' or 'unplug' various force models, this multi-flight phase navigation filter design structure also provides a versatile GPS navigation software engine for both atmospheric and exo-atmospheric navigation or positioning use, thereby streamlining the flight phase or application-dependent software requirements. Thus, a standardized GPS navigation software engine that can reduce the development and maintenance cost of commercial GPS receivers is now possible.

Installing Electronics in Juno Vault

NASA Image and Video Library

2010-12-16

Technicians install components that will aid with guidance, navigation and control of NASA Juno spacecraft. Like most of Juno sensitive electronics, these components are situated within the spacecraft titanium radiation vault.

The sensory ecology of ocean navigation.

PubMed

Lohmann, Kenneth J; Lohmann, Catherine M F; Endres, Courtney S

2008-06-01

How animals guide themselves across vast expanses of open ocean, sometimes to specific geographic areas, has remained an enduring mystery of behavioral biology. In this review we briefly contrast underwater oceanic navigation with terrestrial navigation and summarize the advantages and constraints of different approaches used to analyze animal navigation in the sea. In addition, we highlight studies and techniques that have begun to unravel the sensory cues that underlie navigation in sea turtles, salmon and other ocean migrants. Environmental signals of importance include geomagnetic, chemical and hydrodynamic cues, perhaps supplemented in some cases by celestial cues or other sources of information that remain to be discovered. An interesting similarity between sea turtles and salmon is that both have been hypothesized to complete long-distance reproductive migrations using navigational systems composed of two different suites of mechanisms that function sequentially over different spatial scales. The basic organization of navigation in these two groups of animals may be functionally similar, and perhaps also representative of other long-distance ocean navigators.

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.

Development of a breast navigation program.

PubMed

Shockney, Lillie D; Haylock, Pamela J; Cantril, Cynthia

2013-05-01

To review the development of a navigation program in a major US academic health care institution, and provide guidance for navigation programmatic development in other settings. The Johns Hopkins Breast Center Steering Committee minutes, Hospital Cancer Registry; administrative data, and literature. Incorporating navigation services throughout the cancer continuum, from diagnosis to survivorship, provides guidance for patients with cancer. Navigation processes and programs must remain dynamic, reflecting patient and community needs. Oncology nurses have traditionally performed many tasks associated with navigation, including patient education, psychosocial support, and addressing barriers to care. This article provides an exemplar for nurses developing or enhancing comprehensive breast programs. Copyright © 2013 Elsevier Inc. All rights reserved.

33 CFR 165.838 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, New Orleans...

Code of Federal Regulations, 2014 CFR

2014-07-01

... before closure of the navigational structures, all floating vessels must depart the RNA except as follows... Harbor Navigation Canal, New Orleans, LA. (a) Location. The following is a regulated navigation area (RNA... West of Harvey Locks (WHL) (b) Definitions. As used in this section: (1) Breakaway means a floating...

Implementation of evidence-based patient navigation programs.

PubMed

Freund, Karen M

2017-02-01

Patient navigation refers to a direct patient care role that links patients with clinical providers and their support system and provides individualized support during cancer care, ensuring that patients have access to the knowledge and resources necessary to complete recommended treatment. While most reports have studied the role of patient navigators during the cancer screening or diagnostic process, emerging evidence indicates the benefits of patient navigation during active cancer treatment. Reports in the literature are conflicting on the impact of patient navigation during cancer care and on the benefits to timely or quality care in all populations. Recent sub-analyses of the Patient Navigation Research Program data demonstrated specifically the benefits of targeting patient navigation to the most vulnerable populations, including those with low educational attainment, low income and unstable housing, less social support, multiple comorbidities, and minority race/ethnicity. The implications of the Patient Navigation Research Program are that this resource is best utilized when directed to support the care of patients at locations with known challenges to timely care and for specific patients with risk factors for delays in care, including comorbidities, low educational attainment and low income. Implementation of patient navigation programs requires the following processes: needs assessment, selection of a navigator to meet the community and care needs, supervision and integration of the navigator into clinical processes, and systems support to facilitate the identification and tracking of those patients requiring patient navigation. There is a need for ongoing research on methods to fund and sustain patient navigation programs.

75 FR 50884 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

... 3 and 165 to reflect changes in Coast Guard internal organizational structure. Sector Portland and... 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector... Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River.'' 2. On page 48564...

Survey of symbology for aeronautical charts and electronic displays : navigation aids, airports, lines, and linear patterns

DOT National Transportation Integrated Search

2008-09-01

This industry survey documents the symbols for navigation aids, airports, lines, and linear patterns currently in use by avionics manufactureres and chart providers for depicting aeronautical charting information. Nine avionics display manufacturers ...

Simulator Evaluation of Electronic Radio Aids to Navigation Displays--The Miniexperiment.

DTIC Science & Technology

1980-09-01

COOPIRP K L MARINO DOT-CO-8358s-A UNCLASS IF IE0 EA0-"A SC O.- . 9 8 0 NL ’,I’ll" II 2i0 1111 *Q~j28 12 =- MI(,RO Of)Y 1?[ E tIFION Tli T (HART [EVE...graphic navigation display, (see 17 r’ontin,,ed) L 19. -cu:,tv ..Ssf St ,s report) :UO. 3’-mur~t’ C;Psst [of 11. L.4) 21 No. ot e =,t !22. PrW , UNCLASSIFIED...and Check Rudder 46 19 Proposed Displays for Full-Length Scenarios 49 20 System Configurations 51 LIST OF TABLES Table Title Pa e I Summary of Results 2

46 CFR 121.410 - Electronic position fixing devices.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device, capable...

46 CFR 121.410 - Electronic position fixing devices.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device, capable...

46 CFR 121.410 - Electronic position fixing devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device, capable...

46 CFR 121.410 - Electronic position fixing devices.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device, capable...

46 CFR 121.410 - Electronic position fixing devices.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device, capable...

Breast cancer navigation and patient satisfaction: exploring a community-based patient navigation model in a rural setting.

PubMed

Hook, Ann; Ware, Laurie; Siler, Bobbie; Packard, Abbot

2012-07-01

To explore patient satisfaction among newly diagnosed patients with breast cancer in a rural community setting using a nurse navigation model. Nonexperimental, descriptive study. Large, multispecialty physician outpatient clinic serving about 150 newly diagnosed patients with breast cancer annually at the time of the study. 103 patients using nurse navigation services during a two-year period. A researcher-developed 14-item survey tool using a Likert-type scale was mailed to about 300 navigated patients. Nurse navigation and patient satisfaction. The majority of participants (n = 73, 72%) selected "strongly agree" in each survey statement when questioned about the benefits of nurse navigation. Patients receiving nurse navigation for breast cancer are highly satisfied with the services offered in this setting. Findings from this study offer insight regarding the effectiveness of an individualized supportive care approach to nurses and providers of oncology care. That information can be used to guide the implementation of future nurse navigation programs, determine effective methods of guiding patients through the cancer experience, and aid in promoting the highest standard of oncology care.

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.

Inertial navigation without accelerometers

NASA Astrophysics Data System (ADS)

Boehm, M.

The Kennedy-Thorndike (1932) experiment points to the feasibility of fiber-optic inertial velocimeters, to which state-of-the-art technology could furnish substantial sensitivity and accuracy improvements. Velocimeters of this type would obviate the use of both gyros and accelerometers, and allow inertial navigation to be conducted together with vehicle attitude control, through the derivation of rotation rates from the ratios of the three possible velocimeter pairs. An inertial navigator and reference system based on this approach would probably have both fewer components and simpler algorithms, due to the obviation of the first level of integration in classic inertial navigators.

An alternative ionospheric correction model for global navigation satellite systems

NASA Astrophysics Data System (ADS)

Hoque, M. M.; Jakowski, N.

2015-04-01

The ionosphere is recognized as a major error source for single-frequency operations of global navigation satellite systems (GNSS). To enhance single-frequency operations the global positioning system (GPS) uses an ionospheric correction algorithm (ICA) driven by 8 coefficients broadcasted in the navigation message every 24 h. Similarly, the global navigation satellite system Galileo uses the electron density NeQuick model for ionospheric correction. The Galileo satellite vehicles (SVs) transmit 3 ionospheric correction coefficients as driver parameters of the NeQuick model. In the present work, we propose an alternative ionospheric correction algorithm called Neustrelitz TEC broadcast model NTCM-BC that is also applicable for global satellite navigation systems. Like the GPS ICA or Galileo NeQuick, the NTCM-BC can be optimized on a daily basis by utilizing GNSS data obtained at the previous day at monitor stations. To drive the NTCM-BC, 9 ionospheric correction coefficients need to be uploaded to the SVs for broadcasting in the navigation message. Our investigation using GPS data of about 200 worldwide ground stations shows that the 24-h-ahead prediction performance of the NTCM-BC is better than the GPS ICA and comparable to the Galileo NeQuick model. We have found that the 95 percentiles of the prediction error are about 16.1, 16.1 and 13.4 TECU for the GPS ICA, Galileo NeQuick and NTCM-BC, respectively, during a selected quiet ionospheric period, whereas the corresponding numbers are found about 40.5, 28.2 and 26.5 TECU during a selected geomagnetic perturbed period. However, in terms of complexity the NTCM-BC is easier to handle than the Galileo NeQuick and in this respect comparable to the GPS ICA.

Spatial navigation in young versus older adults

PubMed Central

Gazova, Ivana; Laczó, Jan; Rubinova, Eva; Mokrisova, Ivana; Hyncicova, Eva; Andel, Ross; Vyhnalek, Martin; Sheardova, Katerina; Coulson, Elizabeth J.; Hort, Jakub

2013-01-01

Older age is associated with changes in the brain, including the medial temporal lobe, which may result in mild spatial navigation deficits, especially in allocentric navigation. The aim of the study was to characterize the profile of real-space allocentric (world-centered, hippocampus-dependent) and egocentric (body-centered, parietal lobe dependent) navigation and learning in young vs. older adults, and to assess a possible influence of gender. We recruited healthy participants without cognitive deficits on standard neuropsychological testing, white matter lesions or pronounced hippocampal atrophy: 24 young participants (18–26 years old) and 44 older participants stratified as participants 60–70 years old (n = 24) and participants 71–84 years old (n = 20). All underwent spatial navigation testing in the real-space human analog of the Morris Water Maze, which has the advantage of assessing separately allocentric and egocentric navigation and learning. Of the eight consecutive trials, trials 2–8 were used to reduce bias by a rebound effect (more dramatic changes in performance between trials 1 and 2 relative to subsequent trials). The participants who were 71–84 years old (p < 0.001), but not those 60–70 years old, showed deficits in allocentric navigation compared to the young participants. There were no differences in egocentric navigation. All three groups showed spatial learning effect (p’ s ≤ 0.01). There were no gender differences in spatial navigation and learning. Linear regression limited to older participants showed linear (β = 0.30, p = 0.045) and quadratic (β = 0.30, p = 0.046) effect of age on allocentric navigation. There was no effect of age on egocentric navigation. These results demonstrate that navigation deficits in older age may be limited to allocentric navigation, whereas egocentric navigation and learning may remain preserved. This specific pattern of spatial navigation impairment may help differentiate normal aging from

33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation area (RNA). The Regulated Navigation Area (RNA) encompasses all of the navigable waters of...) Regulations. (1) All commercial vessels must: (i) Maintain a minimum 10% of the vessel's draft as an under... commercial vessel traffic in all locations within this RNA shall keep out of the way of the oncoming deep...

33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

Code of Federal Regulations, 2013 CFR

2013-07-01

... navigation area (RNA). The Regulated Navigation Area (RNA) encompasses all of the navigable waters of...) Regulations. (1) All commercial vessels must: (i) Maintain a minimum 10% of the vessel's draft as an under... commercial vessel traffic in all locations within this RNA shall keep out of the way of the oncoming deep...

33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

Code of Federal Regulations, 2014 CFR

2014-07-01

... navigation area (RNA). The Regulated Navigation Area (RNA) encompasses all of the navigable waters of...) Regulations. (1) All commercial vessels must: (i) Maintain a minimum 10% of the vessel's draft as an under... commercial vessel traffic in all locations within this RNA shall keep out of the way of the oncoming deep...

33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

Code of Federal Regulations, 2011 CFR

2011-07-01

... navigation area (RNA). The Regulated Navigation Area (RNA) encompasses all of the navigable waters of...) Regulations. (1) All commercial vessels must: (i) Maintain a minimum 10% of the vessel's draft as an under... commercial vessel traffic in all locations within this RNA shall keep out of the way of the oncoming deep...

33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

Code of Federal Regulations, 2012 CFR

2012-07-01

... navigation area (RNA). The Regulated Navigation Area (RNA) encompasses all of the navigable waters of...) Regulations. (1) All commercial vessels must: (i) Maintain a minimum 10% of the vessel's draft as an under... commercial vessel traffic in all locations within this RNA shall keep out of the way of the oncoming deep...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

14 CFR 63.61 - Flight navigator courses.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Flight navigator courses. 63.61 Section 63...) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Navigators § 63.61 Flight navigator courses. An applicant for approval of a flight navigator course must submit a letter to the Administrator...

14 CFR 63.61 - Flight navigator courses.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight navigator courses. 63.61 Section 63...) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Navigators § 63.61 Flight navigator courses. An applicant for approval of a flight navigator course must submit a letter to the Administrator...

14 CFR 63.61 - Flight navigator courses.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Flight navigator courses. 63.61 Section 63...) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS Flight Navigators § 63.61 Flight navigator courses. An applicant for approval of a flight navigator course must submit a letter to the Administrator...

33 CFR 100.45 - Establishment of aids to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation incidental to the holding of a regatta or marine parade are private aids to navigation as... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Establishment of aids to navigation. 100.45 Section 100.45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND...

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 § 67.35-10...

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 § 67.35-10...

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 § 67.35-10...

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 § 67.35-10...

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 § 67.35-10...

NFC Internal: An Indoor Navigation System

PubMed Central

Ozdenizci, Busra; Coskun, Vedat; Ok, Kerem

2015-01-01

Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability. PMID:25825976

On Navigation Sensor Error Correction

NASA Astrophysics Data System (ADS)

Larin, V. B.

2016-01-01

The navigation problem for the simplest wheeled robotic vehicle is solved by just measuring kinematical parameters, doing without accelerometers and angular-rate sensors. It is supposed that the steerable-wheel angle sensor has a bias that must be corrected. The navigation parameters are corrected using the GPS. The approach proposed regards the wheeled robot as a system with nonholonomic constraints. The performance of such a navigation system is demonstrated by way of an example

Electromagnetic Navigation Diagnostic Bronchoscopy

PubMed Central

Gildea, Thomas R.; Mazzone, Peter J.; Karnak, Demet; Meziane, Moulay; Mehta, Atul C.

2006-01-01

Rationale: Electromagnetic navigation bronchoscopy using superDimension/Bronchus System is a novel method to increase diagnostic yield of peripheral and mediastinal lung lesions. Objectives: A prospective, open label, single-center, pilot study was conducted to determine the ability of electromagnetic navigation bronchoscopy to sample peripheral lung lesions and mediastinal lymph nodes with standard bronchoscopic instruments and demonstrate safety. Methods: Electromagnetic navigation bronchoscopy was performed using the superDimension/Bronchus system consisting of electromagnetic board, position sensor encapsulated in the tip of a steerable probe, extended working channel, and real-time reconstruction of previously acquired multiplanar computed tomography images. The final distance of the steerable probe to lesion, expected error based on the actual and virtual markers, and procedure yield was gathered. Measurements: 60 subjects were enrolled between December 2004 and September 2005. Mean navigation times were 7 ± 6 min and 2 ± 2 min for peripheral lesions and lymph nodes, respectively. The steerable probe tip was navigated to the target lung area in all cases. The mean peripheral lesions and lymph nodes size was 22.8 ± 12.6 mm and 28.1 ± 12.8 mm. Yield was determined by results obtained during the bronchoscopy per patient. Results: The yield/procedure was 74% and 100% for peripheral lesions and lymph nodes, respectively. A diagnosis was obtained in 80.3% of bronchoscopic procedures. A definitive diagnosis of lung malignancy was made in 74.4% of subjects. Pneumothorax occurred in two subjects. Conclusion: Electromagnetic navigation bronchoscopy is a safe method for sampling peripheral and mediastinal lesions with high diagnostic yield independent of lesion size and location. PMID:16873767

46 CFR 111.75-17 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Navigation lights. 111.75-17 Section 111.75-17 Shipping... REQUIREMENTS Lighting Circuits and Protection § 111.75-17 Navigation lights. Each navigation light system must...-5(a) of this chapter, each navigation light panel must be supplied by a feeder from the emergency...

46 CFR 111.75-17 - Navigation lights.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Navigation lights. 111.75-17 Section 111.75-17 Shipping... REQUIREMENTS Lighting Circuits and Protection § 111.75-17 Navigation lights. Each navigation light system must...-5(a) of this chapter, each navigation light panel must be supplied by a feeder from the emergency...

46 CFR 111.75-17 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Navigation lights. 111.75-17 Section 111.75-17 Shipping... REQUIREMENTS Lighting Circuits and Protection § 111.75-17 Navigation lights. Each navigation light system must...-5(a) of this chapter, each navigation light panel must be supplied by a feeder from the emergency...

46 CFR 111.75-17 - Navigation lights.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Navigation lights. 111.75-17 Section 111.75-17 Shipping... REQUIREMENTS Lighting Circuits and Protection § 111.75-17 Navigation lights. Each navigation light system must...-5(a) of this chapter, each navigation light panel must be supplied by a feeder from the emergency...

46 CFR 111.75-17 - Navigation lights.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Navigation lights. 111.75-17 Section 111.75-17 Shipping... REQUIREMENTS Lighting Circuits and Protection § 111.75-17 Navigation lights. Each navigation light system must...-5(a) of this chapter, each navigation light panel must be supplied by a feeder from the emergency...

Sex differences in navigation strategy and efficiency.

PubMed

Boone, Alexander P; Gong, Xinyi; Hegarty, Mary

2018-05-22

Research on human navigation has indicated that males and females differ in self-reported navigation strategy as well as objective measures of navigation efficiency. In two experiments, we investigated sex differences in navigation strategy and efficiency using an objective measure of strategy, the dual-solution paradigm (DSP; Marchette, Bakker, & Shelton, 2011). Although navigation by shortcuts and learned routes were the primary strategies used in both experiments, as in previous research on the DSP, individuals also utilized route reversals and sometimes found the goal location as a result of wandering. Importantly, sex differences were found in measures of both route selection and navigation efficiency. In particular, males were more likely to take shortcuts and reached their goal location faster than females, while females were more likely to follow learned routes and wander. Self-report measures of strategy were only weakly correlated with objective measures of strategy, casting doubt on their usefulness. This research indicates that the sex difference in navigation efficiency is large, and only partially related to an individual's navigation strategy as measured by the dual-solution paradigm.

Semantic retrieval and navigation in clinical document collections.

PubMed

Kreuzthaler, Markus; Daumke, Philipp; Schulz, Stefan

2015-01-01

Patients with chronic diseases undergo numerous in- and outpatient treatment periods, and therefore many documents accumulate in their electronic records. We report on an on-going project focussing on the semantic enrichment of medical texts, in order to support recall-oriented navigation across a patient's complete documentation. A document pool of 1,696 de-identified discharge summaries was used for prototyping. A natural language processing toolset for document annotation (based on the text-mining framework UIMA) and indexing (Solr) was used to support a browser-based platform for document import, search and navigation. The integrated search engine combines free text and concept-based querying, supported by dynamically generated facets (diagnoses, procedures, medications, lab values, and body parts). The prototype demonstrates the feasibility of semantic document enrichment within document collections of a single patient. Originally conceived as an add-on for the clinical workplace, this technology could also be adapted to support personalised health record platforms, as well as cross-patient search for cohort building and other secondary use scenarios.

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.

Navigational Strategies and Their Neural Correlates

PubMed Central

Deshmukh, Sachin S.

2018-01-01

Animals depend on navigation to find food, water, mate(s), shelter, etc. Different species use diverse strategies that utilise forms of motion- and location-related information derived from the environment to navigate to their goals and back. We start by describing behavioural studies undertaken to unearth different strategies used in navigation. Then we move on to outline what we know about the brain area most associated with spatial navigation, namely the hippocampal formation. While doing so, we first briefly explain the anatomical connections in the area and then proceed to describe the neural correlates that are considered to play a role in navigation. We conclude by looking at how the strategies might interact and complement each other in certain contexts. PMID:29657367

Electronic Health Records Place 1st at Indy 500

MedlinePlus

... Navigation Bar Home Current Issue Past Issues EHR Electronic Health Records Place 1st at Indy 500 Past ... last May's Indy 500 had thousands of personal Electronic Health Records on hand for those attending—and ...

Navigation for the new millennium: Autonomous navigation for Deep Space 1

NASA Technical Reports Server (NTRS)

Reidel, J. E.; Bhaskaran, S.; Synnott, S. P.; Desai, S. D.; Bollman, W. E.; Dumont, P. J.; Halsell, C. A.; Han, D.; Kennedy, B. M.; Null, G. W.;

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..., and temporary construction and borrow areas. (3) In navigation-only projects, the right to permanently...

Design of all-weather celestial navigation system

NASA Astrophysics Data System (ADS)

Sun, Hongchi; Mu, Rongjun; Du, Huajun; Wu, Peng

2018-03-01

In order to realize autonomous navigation in the atmosphere, an all-weather celestial navigation system is designed. The research of celestial navigation system include discrimination method of comentropy and the adaptive navigation algorithm based on the P value. The discrimination method of comentropy is studied to realize the independent switching of two celestial navigation modes, starlight and radio. Finally, an adaptive filtering algorithm based on P value is proposed, which can greatly improve the disturbance rejection capability of the system. The experimental results show that the accuracy of the three axis attitude is better than 10″, and it can work all weather. In perturbation environment, the position accuracy of the integrated navigation system can be increased 20% comparing with the traditional method. It basically meets the requirements of the all-weather celestial navigation system, and it has the ability of stability, reliability, high accuracy and strong anti-interference.

Guidewire navigation in coronary artery stenoses using a novel magnetic navigation system: first clinical experience.

PubMed

Tsuchida, Keiichi; García-García, Héctor M; van der Giessen, Willem J; McFadden, Eugène P; van der Ent, Martin; Sianos, Georgios; Meulenbrug, Hans; Ong, Andrew T L; Serruys, Patrick W

2006-03-01

The objective of this study was to investigate the efficacy of guidewire navigation across coronary artery stenoses using magnetic navigation system (MNS) versus conventional navigation. The MNS is a novel option to facilitate access to target lesions, particularly in tortuous vessels. In an experimental study using a challenging vessel phantom, magnetic-navigated guidewire passage has been reported to reduce fluoroscopy and procedure time significantly. Both magnetic and manual guidewire navigation were attempted in 21 consecutive diseased coronary arteries. The study endpoint was defined as an intraluminal wire position distal to the stenosis. Procedural success was defined as successful guidewire passage without procedural events. Procedure time, amount of contrast, fluoroscopy time, and radiation dose/area product (DAP) were evaluated. There were no procedural events related to either guidewire. Although the lesions attempted had relatively simple and straightforward characteristics, significantly shorter procedure and fluoroscopy time were observed for manual guidewire navigation compared to MNS (median, 40 vs. 120 sec, P=0.001; 38 vs. 105 sec, P=0.001, respectively). Contrast amount and DAP were higher in MNS than in conventional method (median, 13 vs. 9 ml, P=0.018; 215 vs. 73 Gym2, P=0.002, respectively). The magnetic wire did not cross in two vessels. Guidewire navigation using MNS presented a novel, safe, and feasible approach to address coronary artery lesions. Clinical studies are needed to evaluate the potential benefit of the MNS in more complex coronary lesions and tortuous anatomy. Copyright (c) 2006 Wiley-Liss, Inc.

An on-line monitoring system for navigation equipment

NASA Astrophysics Data System (ADS)

Wang, Bo; Yang, Ping; Liu, Jing; Yang, Zhengbo; Liang, Fei

2017-10-01

Civil air navigation equipment is the most important infrastructure of Civil Aviation, which is closely related to flight safety. In addition to regular flight inspection, navigation equipment's patrol measuring, maintenance measuring, running measuring under special weather conditions are the important means of ensuring aviation flight safety. According to the safety maintenance requirements of Civil Aviation Air Traffic Control navigation equipment, this paper developed one on-line monitoring system with independent intellectual property rights for navigation equipment, the system breakthroughs the key technologies of measuring navigation equipment on-line including Instrument Landing System (ILS) and VHF Omni-directional Range (VOR), which also meets the requirements of navigation equipment ground measurement set by the ICAO DOC 8071, it provides technical means of the ground on-line measurement for navigation equipment, improves the safety of navigation equipment operation, and reduces the impact of measuring navigation equipment on airport operation.

Patient Navigation Improves Subsequent Breast Cancer Screening After a Noncancerous Result: Evidence from the Patient Navigation in Medically Underserved Areas Study.

PubMed

Molina, Yamile; Kim, Sage J; Berrios, Nerida; Glassgow, Anne Elizabeth; San Miguel, Yazmin; Darnell, Julie S; Pauls, Heather; Vijayasiri, Ganga; Warnecke, Richard B; Calhoun, Elizabeth A

2018-03-01

Past efforts to assess patient navigation on cancer screening utilization have focused on one-time uptake, which may not be sufficient in the long term. This is partially due to limited resources for in-person, longitudinal patient navigation. We examine the effectiveness of a low-intensity phone- and mail-based navigation on multiple screening episodes with a focus on screening uptake after receiving noncancerous results during a previous screening episode. The is a secondary analysis of patients who participated in a randomized controlled patient navigation trial in Chicago. Participants include women referred for a screening mammogram, aged 50-74 years, and with a history of benign/normal screening results. Navigation services focused on identification of barriers and intervention via shared decision-making processes. A multivariable logistic regression intent-to-treat model was used to examine differences in odds of obtaining a screening mammogram within 2 years of the initial mammogram (yes/no) between navigated and non-navigated women. Sensitivity analyses were conducted to explore patterns across subsets of participants (e.g., navigated women successfully contacted before the initial appointment; women receiving care at Hospital C). The final sample included 2,536 women (741 navigated, 1,795 non-navigated). Navigated women exhibited greater odds of obtaining subsequent screenings relative to women in the standard care group in adjusted models and analyses including women who received navigation before the initial appointment. Our findings suggest that low-intensity navigation services can improve follow-up screening among women who receive a noncancerous result. Further investigation is needed to confirm navigation's impacts on longitudinal screening.

Navigation Flight Test Results from the Low Power Transceiver Communications and Navigation Demonstration on Shuttle (CANDOS) Experiment

NASA Technical Reports Server (NTRS)

Haas, Lin; Massey, Christopher; Baraban, Dmitri

2003-01-01

This paper presents the Global Positioning System (GPS) navigation results from the Communications and Navigation Demonstration on Shuttle (CANDOS) experiment flown on STS-107. This experiment was the initial flight of a Low Power Transceiver (LPT) that featured high capacity space- space and space-ground communications and GPS- based navigation capabilities. The LPT also hosted the GPS Enhanced Orbit Determination Experiment (GEODE) orbit determination software. All CANDOS test data were recovered during the mission using LPT communications links via the Tracking and Data Relay Satellite System (TDRSS). An overview of the LPT s navigation software and the GPS experiment timeline is presented, along with comparisons of test results to the NASA Johnson Space Center (JSC) real-time ground navigation vectors and Best Estimate of Trajectory (BET).

Navigation and Landing Transition Strategy

DOT National Transportation Integrated Search

2002-08-01

Attached is the Federal Aviation Administration's (FAA) Navigation and Landing Transition Strategy. This report defines the satellite navigation transition strategy that considers the vulnerability of the Global Positioning System (GPS) and describes...

Honeybees consolidate navigation memory during sleep.

PubMed

Beyaert, Lisa; Greggers, Uwe; Menzel, Randolf

2012-11-15

Sleep is known to support memory consolidation in animals, including humans. Here we ask whether consolidation of novel navigation memory in honeybees depends on sleep. Foragers were exposed to a forced navigation task in which they learned to home more efficiently from an unexpected release site by acquiring navigational memory during the successful homing flight. This task was quantified using harmonic radar tracking and applied to bees that were equipped with a radio frequency identification device (RFID). The RFID was used to record their outbound and inbound flights and continuously monitor their behavior inside the colony, including their rest during the day and sleep at night. Bees marked with the RFID behaved normally inside and outside the hive. Bees slept longer during the night following forced navigation tasks, but foraging flights of different lengths did not lead to different rest times during the day or total sleep time during the night. Sleep deprivation before the forced navigation task did not alter learning and memory acquired during the task. However, sleep deprivation during the night after forced navigation learning reduced the probability of returning successfully to the hive from the same release site. It is concluded that consolidation of novel navigation memory is facilitated by night sleep in bees.

32 CFR 644.3 - Navigation Projects.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 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... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...

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... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...

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... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...

Costs and Outcomes Evaluation of Patient Navigation Following Abnormal Cancer Screening: Evidence from the Patient Navigation Research Program

PubMed Central

Bensink, Mark E.; Ramsey, Scott D.; Battaglia, Tracy; Fiscella, Kevin; Hurd, Thelma C.; McKoy, June M.; Patierno, Steven R.; Raich, Peter C.; Seiber, Eric E.; Mears, Victoria Warren; Whitley, Elizabeth; Paskett, Electra D.; Mandelblatt, Jeanne S.

2013-01-01

Background Navigators can facilitate timely access to cancer services but there are little data on their economic impact. Methods We conduct a cost-consequence analysis of navigation vs. usual care among 10,521 individuals with abnormal breast, cervix, colorectal or prostate cancer screening results who enrolled in the Patient Navigation Research Program study from January 1 2006 to March 31 2010. Navigation costs included diagnostic evaluation, patient and staff time, materials, and overhead. Consequences or outcomes were time to diagnostic resolution and probability of resolution. Differences in costs and outcomes were evaluated using multi-level, mixed-effects regression adjusting for age, race/ethnicity, language, marital status, insurance, cancer, and site clustering. Results Most individuals were minority (70.7%) and un- or publically-insured (72.7%). Diagnostic resolution was higher for navigation vs. usual care at 180 (56.2% vs. 53.8%, p=0.008) and 270 days: 70.0% vs. 68.2%, p<0.001). While there were no differences in average days to resolution (110 vs. 109 days, p=.63), the probability of ever having diagnostic resolution was higher for navigation vs. usual care (84.5% vs. 79.6%, p <0.001). The added cost of navigation vs. usual care was $275 per patient (95% CI $260 – $290, p <0.001). There was no significant difference in stage distribution among the 12.4% of navigated vs. 11% of usual care patients diagnosed with cancer. Conclusions Navigation adds costs and modestly increases the probability of diagnostic resolution among patients with abnormal screening tests. Navigation is only likely to be cost-effective if improved resolution translates into earlier cancer stage at diagnosis. PMID:24166217

Boston Patient Navigation Research Program: the impact of navigation on time to diagnostic resolution after abnormal cancer screening.

PubMed

Battaglia, Tracy A; Bak, Sharon M; Heeren, Timothy; Chen, Clara A; Kalish, Richard; Tringale, Stephen; Taylor, James O; Lottero, Barbara; Egan, A Patrick; Thakrar, Nisha; Freund, Karen M

2012-10-01

There is a need for controlled studies to assess the impact of patient navigation in vulnerable cancer populations. Boston Patient Navigation Research Program conducted a quasi-experimental patient navigation intervention across six federally qualified inner-city community health centers, three assigned to a breast cancer navigation intervention and three assigned to a cervical cancer navigation intervention; each group then served as the control for the other. Eligible women had an abnormal breast or cervical cancer screening test conducted at one of the participating health centers during a baseline (2004-2005) or intervention period (2007-2008). Kaplan-Meier survival curves and proportional hazards regression examined the effect of patient navigation on time to definitive diagnosis, adjusting for covariates, clustering by clinic and differences between the baseline and intervention period. We enrolled 997 subjects in the baseline period and 3,041 subjects during the intervention period, of whom 1,497 were in the navigated arm, and 1,544 in the control arm. There was a significant decrease in time to diagnosis for subjects in the navigated group compared with controls among those with a cervical screening abnormality [aHR 1.46; 95% confidence interval (CI), 1.1-1.9]; and among those with a breast cancer screening abnormality that resolved after 60 days (aHR 1.40; 95% CI, 1.1-1.9), with no differences before 60 days. This study documents a benefit of patient navigation on time to diagnosis among a racially/ethnically diverse inner city population. Patient navigation may address cancer health disparities by reducing time to diagnosis following an abnormal cancer-screening event. 2012 AACR

FLASH LIDAR Based Relative Navigation

NASA Technical Reports Server (NTRS)

Brazzel, Jack; Clark, Fred; Milenkovic, Zoran

2014-01-01

Relative navigation remains the most challenging part of spacecraft rendezvous and docking. In recent years, flash LIDARs, have been increasingly selected as the go-to sensors for proximity operations and docking. Flash LIDARS are generally lighter and require less power that scanning Lidars. Flash LIDARs do not have moving parts, and they are capable of tracking multiple targets as well as generating a 3D map of a given target. However, there are some significant drawbacks of Flash Lidars that must be resolved if their use is to be of long-term significance. Overcoming the challenges of Flash LIDARs for navigation-namely, low technology readiness level, lack of historical performance data, target identification, existence of false positives, and performance of vision processing algorithms as intermediaries between the raw sensor data and the Kalman filter-requires a world-class testing facility, such as the Lockheed Martin Space Operations Simulation Center (SOSC). Ground-based testing is a critical step for maturing the next-generation flash LIDAR-based spacecraft relative navigation. This paper will focus on the tests of an integrated relative navigation system conducted at the SOSC in January 2014. The intent of the tests was to characterize and then improve the performance of relative navigation, while addressing many of the flash LIDAR challenges mentioned above. A section on navigation performance and future recommendation completes the discussion.

Optimal scheme of star observation of missile-borne inertial navigation system/stellar refraction integrated navigation

NASA Astrophysics Data System (ADS)

Lu, Jiazhen; Yang, Lie

2018-05-01

To achieve accurate and completely autonomous navigation for spacecraft, inertial/celestial integrated navigation gets increasing attention. In this study, a missile-borne inertial/stellar refraction integrated navigation scheme is proposed. Position Dilution of Precision (PDOP) for stellar refraction is introduced and the corresponding equation is derived. Based on the condition when PDOP reaches the minimum value, an optimized observation scheme is proposed. To verify the feasibility of the proposed scheme, numerical simulation is conducted. The results of the Extended Kalman Filter (EKF) and Unscented Kalman Filter (UKF) are compared and impact factors of navigation accuracy are studied in the simulation. The simulation results indicated that the proposed observation scheme has an accurate positioning performance, and the results of EKF and UKF are similar.

Optimal scheme of star observation of missile-borne inertial navigation system/stellar refraction integrated navigation.

PubMed

Lu, Jiazhen; Yang, Lie

2018-05-01

To achieve accurate and completely autonomous navigation for spacecraft, inertial/celestial integrated navigation gets increasing attention. In this study, a missile-borne inertial/stellar refraction integrated navigation scheme is proposed. Position Dilution of Precision (PDOP) for stellar refraction is introduced and the corresponding equation is derived. Based on the condition when PDOP reaches the minimum value, an optimized observation scheme is proposed. To verify the feasibility of the proposed scheme, numerical simulation is conducted. The results of the Extended Kalman Filter (EKF) and Unscented Kalman Filter (UKF) are compared and impact factors of navigation accuracy are studied in the simulation. The simulation results indicated that the proposed observation scheme has an accurate positioning performance, and the results of EKF and UKF are similar.

14 CFR 121.349 - Communication and navigation equipment for operations under VFR over routes not navigated by...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Communication and navigation equipment for... § 121.349 Communication and navigation equipment for operations under VFR over routes not navigated by... receiver providing visual and aural signals; and (iii) One ILS receiver; and (3) Any RNAV system used to...

Quantum imaging for underwater arctic navigation

NASA Astrophysics Data System (ADS)

Lanzagorta, Marco

2017-05-01

The precise navigation of underwater vehicles is a difficult task due to the challenges imposed by the variable oceanic environment. It is particularly difficult if the underwater vehicle is trying to navigate under the Arctic ice shelf. Indeed, in this scenario traditional navigation devices such as GPS, compasses and gyrocompasses are unavailable or unreliable. In addition, the shape and thickness of the ice shelf is variable throughout the year. Current Arctic underwater navigation systems include sonar arrays to detect the proximity to the ice. However, these systems are undesirable in a wartime environment, as the sound gives away the position of the underwater vehicle. In this paper we briefly describe the theoretical design of a quantum imaging system that could allow the safe and stealthy navigation of underwater Arctic vehicles.

Experiment D009: Simple navigation

NASA Technical Reports Server (NTRS)

Silva, R. M.; Jorris, T. R.; Vallerie, E. M., III

1971-01-01

Space position-fixing techniques have been investigated by collecting data on the observable phenomena of space flight that could be used to solve the problem of autonomous navigation by the use of optical data and manual computations to calculate the position of a spacecraft. After completion of the developmental and test phases, the product of the experiment would be a manual-optical technique of orbital space navigation that could be used as a backup to onboard and ground-based spacecraft-navigation systems.

Analysis of key technologies in geomagnetic navigation

NASA Astrophysics Data System (ADS)

Zhang, Xiaoming; Zhao, Yan

2008-10-01

Because of the costly price and the error accumulation of high precise Inertial Navigation Systems (INS) and the vulnerability of Global Navigation Satellite Systems (GNSS), the geomagnetic navigation technology, a passive autonomous navigation method, is paid attention again. Geomagnetic field is a natural spatial physical field, and is a function of position and time in near earth space. The navigation technology based on geomagnetic field is researched in a wide range of commercial and military applications. This paper presents the main features and the state-of-the-art of Geomagnetic Navigation System (GMNS). Geomagnetic field models and reference maps are described. Obtaining, modeling and updating accurate Anomaly Magnetic Field information is an important step for high precision geomagnetic navigation. In addition, the errors of geomagnetic measurement using strapdown magnetometers are analyzed. The precise geomagnetic data is obtained by means of magnetometer calibration and vehicle magnetic field compensation. According to the measurement data and reference map or model of geomagnetic field, the vehicle's position and attitude can be obtained using matching algorithm or state-estimating method. The tendency of geomagnetic navigation in near future is introduced at the end of this paper.

Two-dimensional laser Doppler velocimeter and its integrated navigation with a strapdown inertial navigation system.

PubMed

Wang, Qi; Gao, Chunfeng; Zhou, Jian; Wei, Guo; Nie, Xiaoming; Long, Xingwu

2018-05-01

In the field of land navigation, a laser Doppler velocimeter (LDV) can be used to provide the velocity of a vehicle for an integrated navigation system with a strapdown inertial navigation system. In order to suppress the influence of vehicle jolts on a one-dimensional (1D) LDV, this paper designs a split-reuse two-dimensional (2D) LDV. The velocimeter is made up of two 1D velocimeter probes that are mirror-mounted. By the different effects of the vertical vibration on the two probes, the velocimeter can calculate the forward velocity and the vertical velocity of a vehicle. The results of the vehicle-integrated navigation experiments show that the 2D LDV not only can actually suppress the influence of vehicle jolts and greatly improve the navigation positioning accuracy, but also can give high-precision altitude information. The maximum horizontal position errors of the two experiments are 2.6 m and 3.2 m in 1.9 h, and the maximum altitude errors are 0.24 m and 0.22 m, respectively.

Unraveling the neural basis of insect navigation.

PubMed

Heinze, Stanley

2017-12-01

One of the defining features of animals is their ability to navigate their environment. Using behavioral experiments this topic has been under intense investigation for nearly a century. In insects, this work has largely focused on the remarkable homing abilities of ants and bees. More recently, the neural basis of navigation shifted into the focus of attention. Starting with revealing the neurons that process the sensory signals used for navigation, in particular polarized skylight, migratory locusts became the key species for delineating navigation-relevant regions of the insect brain. Over the last years, this work was used as a basis for research in the fruit fly Drosophila and extraordinary progress has been made in illuminating the neural underpinnings of navigational processes. With increasingly detailed understanding of navigation circuits, we can begin to ask whether there is a fundamentally shared concept underlying all navigation behavior across insects. This review highlights recent advances and puts them into the context of the behavioral work on ants and bees, as well as the circuits involved in polarized-light processing. A region of the insect brain called the central complex emerges as the common substrate for guiding navigation and its highly organized neuroarchitecture provides a framework for future investigations potentially suited to explain all insect navigation behavior at the level of identified neurons. Copyright © 2017 Elsevier Inc. All rights reserved.

Navigation Performance of Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.

2013-01-01

GPS has been used for spacecraft navigation for many years center dot In support of this, the US has committed that future GPS satellites will continue to provide signals in the Space Service Volume center dot NASA is working with international agencies to obtain similar commitments from other providers center dot In support of this effort, I simulated multi-constellation navigation in the Space Service Volume In this presentation, I extend the work to examine the navigational benefits and drawbacks of the new constellations center dot A major benefit is the reduced geometric dilution of precision (GDOP). I show that there is a substantial reduction in GDOP by using all of the GNSS constellations center dot The increased number of GNSS satellites broadcasting does produce mutual interference, raising the noise floor. A near/far signal problem can also occur where a nearby satellite drowns out satellites that are far away. - In these simulations, no major effect was observed Typically, the use of multi-constellation GNSS navigation improves GDOP by a factor of two or more over GPS alone center dot In addition, at the higher altitudes, four satellite solutions can be obtained much more often center dot This show the value of having commitments to provide signals in the Space Service Volume Besides a commitment to provide a minimum signal in the Space Service Volume, detailed signal gain information is useful for mission planning center dot Knowledge of group and phase delay over the pattern would also reduce the navigational uncertainty

Shuttle OFT Level C navigation requirements

NASA Technical Reports Server (NTRS)

1980-01-01

Detailed requirements for the orbital operations computer loads, OPS 2, and OPS 8 are given. These requirements represent the total on-orbit/rendezvous navigation baseline requirements for the following principal functions: on-orbital/rendezvous navigation sequencer; on-orbit/rendezvous UPP sequencer; on-orbit rendezvous navigation; on-orbit prediction; on-orbit user parameter processing; and landing Site update.

The attribution of success when using navigation aids.

PubMed

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. 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.

Costs and outcomes evaluation of patient navigation after abnormal cancer screening: evidence from the Patient Navigation Research Program.

PubMed

Bensink, Mark E; Ramsey, Scott D; Battaglia, Tracy; Fiscella, Kevin; Hurd, Thelma C; McKoy, June M; Patierno, Steven R; Raich, Peter C; Seiber, Eric E; Warren-Mears, Victoria; Whitley, Elizabeth; Paskett, Electra D; Mandelblatt, S

2014-02-15

Navigators can facilitate timely access to cancer services, but to the authors' knowledge there are little data available regarding their economic impact. The authors conducted a cost-consequence analysis of navigation versus usual care among 10,521 individuals with abnormal breast, cervical, colorectal, or prostate cancer screening results who enrolled in the Patient Navigation Research Program study from January 1, 2006 to March 31, 2010. Navigation costs included diagnostic evaluation, patient and staff time, materials, and overhead. Consequences or outcomes were time to diagnostic resolution and probability of resolution. Differences in costs and outcomes were evaluated using multilevel, mixed-effects regression modeling adjusting for age, race/ethnicity, language, marital status, insurance status, cancer, and site clustering. The majority of individuals were members of a minority (70.7%) and uninsured or publically insured (72.7%). Diagnostic resolution was higher for navigation versus usual care at 180 days (56.2% vs 53.8%; P = .008) and 270 days (70.0% vs 68.2%; P < .001). Although there were no differences in the average number of days to resolution between the 2 groups (110 days vs 109 days; P = .63), the probability of ever having diagnostic resolution was higher for the navigation group versus the usual-care group (84.5% vs 79.6%; P < .001). The added cost of navigation versus usual care was $275 per patient (95% confidence interval, $260-$290; P < .001). There was no significant difference in stage distribution among the 12.4% of patients in the navigation group vs 11% of the usual-care patients diagnosed with cancer. Navigation adds costs and modestly increases the probability of diagnostic resolution among patients with abnormal screening test results. Navigation is only likely to be cost-effective if improved resolution translates into an earlier cancer stage at the time of diagnosis. © 2013 American Cancer Society.

Intelligent personal navigator supported by knowledge-based systems for estimating dead reckoning navigation parameters

NASA Astrophysics Data System (ADS)

Moafipoor, Shahram

Personal navigators (PN) have been studied for about a decade in different fields and applications, such as safety and rescue operations, security and emergency services, and police and military applications. The common goal of all these applications is to provide precise and reliable position, velocity, and heading information of each individual in various environments. In the PN system developed in this dissertation, the underlying assumption is that the system does not require pre-existing infrastructure to enable pedestrian navigation. To facilitate this capability, a multisensor system concept, based on the Global Positioning System (GPS), inertial navigation, barometer, magnetometer, and a human pedometry model has been developed. An important aspect of this design is to use the human body as navigation sensor to facilitate Dead Reckoning (DR) navigation in GPS-challenged environments. The system is designed predominantly for outdoor environments, where occasional loss of GPS lock may happen; however, testing and performance demonstration have been extended to indoor environments. DR navigation is based on a relative-measurement approach, with the key idea of integrating the incremental motion information in the form of step direction (SD) and step length (SL) over time. The foundation of the intelligent navigation system concept proposed here rests in exploiting the human locomotion pattern, as well as change of locomotion in varying environments. In this context, the term intelligent navigation represents the transition from the conventional point-to-point DR to dynamic navigation using the knowledge about the mechanism of the moving person. This approach increasingly relies on integrating knowledge-based systems (KBS) and artificial intelligence (AI) methodologies, including artificial neural networks (ANN) and fuzzy logic (FL). In addition, a general framework of the quality control for the real-time validation of the DR processing is proposed, based on a

Polarized skylight navigation.

PubMed

Hamaoui, Moshe

2017-01-20

Vehicle state estimation is an essential prerequisite for navigation. The present approach seeks to use skylight polarization to facilitate state estimation under autonomous unconstrained flight conditions. Atmospheric scattering polarizes incident sunlight such that solar position is mathematically encoded in the resulting skylight polarization pattern. Indeed, several species of insects are able to sense skylight polarization and are believed to navigate polarimetrically. Sun-finding methodologies for polarized skylight navigation (PSN) have been proposed in the literature but typically rely on calibration updates to account for changing atmospheric conditions and/or are limited to 2D operation. To address this technology gap, a gradient-based PSN solution is developed based upon the Rayleigh sky model. The solution is validated in simulation, and effects of measurement error and changing atmospheric conditions are investigated. Finally, an experimental effort is described wherein polarimetric imagery is collected, ground-truth is established through independent imager-attitude measurement, the gradient-based PSN solution is applied, and results are analyzed.

Patient navigation in breast cancer: a systematic review.

PubMed

Robinson-White, Stephanie; Conroy, Brenna; Slavish, Kathleen H; Rosenzweig, Margaret

2010-01-01

The role of the patient navigator in cancer care and specifically in breast cancer care has grown to incorporate many titles and functions. To better evaluate the outcomes of patient navigation in breast cancer care, a comprehensive review of empiric literature detailing the efficacy of breast cancer navigation on breast cancer outcomes (screening, diagnosis, treatment, and participation in clinical research) was performed. Published articles were reviewed if published in the scientific literature between January 1990 and April 2009. Searches were conducted using PubMed and Ovid databases. Search terms included MeSH (Medical Subject Headings) terms, "patient navigator," "navigation," "breast cancer," and "adherence." Data-based literature indicates that the role of patient navigation is diverse with multiple roles and targeted populations. Navigation across many aspects of the breast cancer disease trajectory improves adherence to breast cancer care. The empiric review found that navigation interventions have been more commonly applied in breast cancer screening and early diagnosis than for adherence to treatment. There is evidence supporting the role of patient navigation in breast cancer to improve many aspects of breast cancer care. Data describing the role of patient navigation in breast cancer will assist in better defining future direction for the breast navigation role. Ongoing research will better inform issues related to role definition, integration into clinical breast cancer care, impact on quality of life, cost-effectiveness, and sustainability.

NAVIGATION PERFORMANCE IN HIGH EARTH ORBITS USING NAVIGATOR GPS RECEIVER

NASA Technical Reports Server (NTRS)

Bamford, William; Naasz, Bo; Moreau, Michael C.

2006-01-01

NASA GSFC has developed a GPS receiver that can acquire and track GPS signals with sensitivity significantly lower than conventional GPS receivers. This opens up the possibility of using GPS based navigation for missions in high altitude orbit, such as Geostationary Operational Environmental Satellites (GOES) in a geostationary orbit, and the Magnetospheric MultiScale (MMS) Mission, in highly eccentric orbits extending to 12 Earth radii and higher. Indeed much research has been performed to study the feasibility of using GPS navigation in high Earth orbits and the performance achievable. Recently, GSFC has conducted a series of hardware in-the-loop tests to assess the performance of this new GPS receiver in various high Earth orbits of interest. Tracking GPS signals to down to approximately 22-25 dB-Hz, including signals from the GPS transmitter side-lobes, steady-state navigation performance in a geostationary orbit is on the order of 10 meters. This paper presents the results of these tests, as well as sensitivity analysis to such factors as ionosphere masks, use of GPS side-lobe signals, and GPS receiver sensitivity.

33 CFR 207.800 - Collection of navigation statistics.

Code of Federal Regulations, 2013 CFR

2013-07-01

... statistics. 207.800 Section 207.800 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.800 Collection of navigation statistics. (a... Revenue Service, Customs Service, Maritime Administration, Department of Transportation, and Department of...

33 CFR 207.800 - Collection of navigation statistics.

Code of Federal Regulations, 2014 CFR

2014-07-01

... statistics. 207.800 Section 207.800 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.800 Collection of navigation statistics. (a... Revenue Service, Customs Service, Maritime Administration, Department of Transportation, and Department of...

33 CFR 207.800 - Collection of navigation statistics.

Code of Federal Regulations, 2011 CFR

2011-07-01

... statistics. 207.800 Section 207.800 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.800 Collection of navigation statistics. (a... Revenue Service, Customs Service, Maritime Administration, Department of Transportation, and Department of...

33 CFR 207.800 - Collection of navigation statistics.

Code of Federal Regulations, 2012 CFR

2012-07-01

... statistics. 207.800 Section 207.800 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.800 Collection of navigation statistics. (a... Revenue Service, Customs Service, Maritime Administration, Department of Transportation, and Department of...

Compact autonomous navigation system (CANS)

NASA Astrophysics Data System (ADS)

Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.

2017-11-01

Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].

Remote navigation systems in electrophysiology.

PubMed

Schmidt, Boris; Chun, Kyoung Ryul Julian; Tilz, Roland R; Koektuerk, Buelent; Ouyang, Feifan; Kuck, Karl-Heinz

2008-11-01

Today, atrial fibrillation (AF) is the dominant indication for catheter ablation in big electrophysiologists (EP) centres. AF ablation strategies are complex and technically challenging. Therefore, it would be desirable that technical innovations pursue the goal to improve catheter stability to increase the procedural success and most importantly to increase safety by helping to avoid serious complications. The most promising technical innovation aiming at the aforementioned goals is remote catheter navigation and ablation. To date, two different systems, the NIOBE magnetic navigation system (MNS, Stereotaxis, USA) and the Sensei robotic navigation system (RNS, Hansen Medical, USA), are commercially available. The following review will introduce the basic principles of the systems, will give an insight into the merits and demerits of remote navigation, and will further focus on the initial clinical experience at our centre with focus on pulmonary vein isolation (PVI) procedures.

Limitations of navigation through Nubaria canal, Egypt.

PubMed

Samuel, Magdy G

2014-03-01

Alexandria port is the main Egyptian port at the Mediterranean Sea. It is connected to the Nile River through Nubaria canal, which is a main irrigation canal. The canal was designed to irrigate eight hundred thousand acres of agricultural lands, along its course which extends 100 km. The canal has three barrages and four locks to control the flow and allow light navigation by some small barges. Recently, it was decided to improve the locks located on the canal. More than 40 million US$ was invested in these projects. This decision was taken to allow larger barges and increase the transported capacity through the canal. On the other hand, navigation through canals and restricted shallow waterways is affected by several parameters related to both the channel and the vessel. Navigation lane width as well as vessel speed and maneuverability are affected by both the channel and vessel dimensions. Moreover, vessel dimensions and speed will affect the canal stability. In Egypt, there are no guide rules for navigation through narrow and shallow canals such Nubaria. This situation threatens the canal stability and safety of navigation through it. This paper discussed the characteristics of Nubaria canal and the guide rules for navigation in shallow restricted water ways. Dimensions limitation for barges navigating through Nubaria canal is presented. New safe operation rules for navigation in Nubaria canal are also presented. Moreover, the implication of navigation through locks on canal discharge is estimated.

76 FR 63934 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

... the Road, navigation regulations and equipment, routing measures, marine information, diving safety... Road, navigation regulations and equipment, routing measures, marine information, diving safety, and... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2011-0204] Navigation Safety Advisory...

NASA tracking ship navigation systems

NASA Technical Reports Server (NTRS)

Mckenna, J. J.

1976-01-01

The ship position and attitude measurement system that was installed aboard the tracking ship Vanguard is described. An overview of the entire system is given along with a description of how precise time and frequency is utilized. The instrumentation is broken down into its basic components. Particular emphasis is given to the inertial navigation system. Each navigation system used, a mariner star tracker, navigation satellite system, Loran C and OMEGA in conjunction with the inertial system is described. The accuracy of each system is compared along with their limitations.

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

Waves at Navigation Structures

DTIC Science & Technology

2014-10-27

upgrades the Coastal Modeling System’s (CMS) wave model CMS-Wave, a phase-averaged spectral wave model, and BOUSS-2D, a Boussinesq -type nonlinear wave...nearshore wave processes in practical applications. These capabilities facilitate optimization of innovative infrastructure for navigation systems to...navigation systems . The advanced models develop probabilistic engineering design estimates for rehabilitation of coastal structures to evaluate the

Stereotaxy, navigation and the temporal concatenation.

PubMed

Apuzzo, M L; Chen, J C

1999-01-01

Nautical and cerebral navigation share similar elements of functional need and similar developmental pathways. The need for orientation necessitates the development of appropriate concepts, and such concepts are dependent on technology for practical realization. Occasionally, a concept precedes technology in time and requires periods of delay for appropriate development. A temporal concatenation exists where time allows the additive as need, concept and technology ultimately provide an endpoint of elegant solution. Nautical navigation has proceeded through periods of dead reckoning and celestial navigation to satellite orientation with associated refinements of instrumentation and charts for guidance. Cerebral navigation has progressed from craniometric orientation and burr hole mounted guidance systems to simple rectolinear and arc-centered devices based on radiographs to guidance by complex anatomical and functional maps provided as an amalgam of modern imaging modes. These maps are now augmented by complex frame and frameless systems which allow not only precise orientation, but also point and volumetric action. These complex technical modalities required and developed in part from elements of maritime navigation that have been translated to cerebral navigation in a temporal concatenation. Copyright 2000 S. Karger AG, Basel

Autonomous Deep-Space Optical Navigation Project

NASA Technical Reports Server (NTRS)

D'Souza, Christopher

2014-01-01

This project will advance the Autonomous Deep-space navigation capability applied to Autonomous Rendezvous and Docking (AR&D) Guidance, Navigation and Control (GNC) system by testing it on hardware, particularly in a flight processor, with a goal of limited testing in the Integrated Power, Avionics and Software (IPAS) with the ARCM (Asteroid Retrieval Crewed Mission) DRO (Distant Retrograde Orbit) Autonomous Rendezvous and Docking (AR&D) scenario. The technology, which will be harnessed, is called 'optical flow', also known as 'visual odometry'. It is being matured in the automotive and SLAM (Simultaneous Localization and Mapping) applications but has yet to be applied to spacecraft navigation. In light of the tremendous potential of this technique, we believe that NASA needs to design a optical navigation architecture that will use this technique. It is flexible enough to be applicable to navigating around planetary bodies, such as asteroids.

Regionalized Lunar South Pole Surface Navigation System Analysis

NASA Technical Reports Server (NTRS)

Welch, Bryan W.

2008-01-01

Apollo missions utilized Earth-based assets for navigation because the landings took place at lunar locations in constant view from the Earth. The new exploration campaign to the lunar south pole region will have limited Earth visibility, but the extent to which a navigation system comprised solely of Earth-based tracking stations will provide adequate navigation solutions in this region is unknown. This report presents a dilution-of-precision (DoP)-based, stationary surface navigation analysis of the performance of multiple lunar satellite constellations, Earth-based deep space network assets, and combinations thereof. Results show that kinematic and integrated solutions cannot be provided by the Earth-based deep space network stations. Also, the stationary surface navigation system needs to be operated either as a two-way navigation system or as a one-way navigation system with local terrain information, while the position solution is integrated over a short duration of time with navigation signals being provided by a lunar satellite constellation.

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2013 CFR

2013-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2012 CFR

2012-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2014 CFR

2014-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

Navigation Performance of Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.

2013-01-01

This paper extends the results I reported at this year's ION International Technical Meeting on multi-constellation GNSS coverage by showing how the use of multi-constellation GNSS improves Geometric Dilution of Precision (GDOP). Originally developed to provide position, navigation, and timing for terrestrial users, GPS has found increasing use for in space for precision orbit determination, precise time synchronization, real-time spacecraft navigation, and three-axis attitude control of Earth orbiting satellites. With additional Global Navigation Satellite Systems (GNSS) coming into service (GLONASS, Galileo, and Beidou) and the development of Satellite Based Augmentation Services, it is possible to obtain improved precision by using evolving multi-constellation receiver. The Space Service Volume formally defined as the volume of space between three thousand kilometers altitude and geosynchronous altitude ((is) approximately 36,500 km), with the volume below three thousand kilometers defined as the Terrestrial Service Volume (TSV). The USA has established signal requirements for the Space Service Volume (SSV) as part of the GPS Capability Development Documentation (CDD). Diplomatic efforts are underway to extend Space service Volume commitments to the other Position, Navigation, and Timing (PNT) service providers in an effort to assure that all space users will benefit from the enhanced capabilities of interoperating GNSS services in the space domain.

77 FR 67658 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-13

... the Road, navigation regulations and equipment, routing measures, marine information, diving safety... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2012-0212] Navigation Safety Advisory... Navigation Safety Advisory Council (NAVSAC) will meet on November 28 and 29, 2012 in Tampa, Florida, to...

78 FR 68077 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-13

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2013-0194] Navigation Safety Advisory.... SUMMARY: The Navigation Safety Advisory Council (NAVSAC) will meet December 3-4, 2013, in Portsmouth... Rules of the Road; navigation regulations and equipment; routing measures; marine information; diving...

78 FR 18615 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2013-0194] Navigation Safety Advisory.... SUMMARY: The Navigation Safety Advisory Council (NAVSAC) will meet April 10-11, 2013, in Arlington... Rules of the Road; navigation regulations and equipment; routing measures; marine information; diving...

76 FR 21772 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-18

..., routing measures, marine information, diving safety, and aids to navigation systems. Agenda The NAVSAC... discussion of autonomous unmanned vessels and discuss their implications for the Inland Navigation Rules. A... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2011-0204] Navigation Safety Advisory...

Pose Measurement Performance of the Argon Relative Navigation Sensor Suite in Simulated Flight Conditions

NASA Technical Reports Server (NTRS)

Galante, Joseph M.; Eepoel, John Van; Strube, Matt; Gill, Nat; Gonzalez, Marcelo; Hyslop, Andrew; Patrick, Bryan

2012-01-01

Argon is a flight-ready sensor suite with two visual cameras, a flash LIDAR, an on- board flight computer, and associated electronics. Argon was designed to provide sensing capabilities for relative navigation during proximity, rendezvous, and docking operations between spacecraft. A rigorous ground test campaign assessed the performance capability of the Argon navigation suite to measure the relative pose of high-fidelity satellite mock-ups during a variety of simulated rendezvous and proximity maneuvers facilitated by robot manipulators in a variety of lighting conditions representative of the orbital environment. A brief description of the Argon suite and test setup are given as well as an analysis of the performance of the system in simulated proximity and rendezvous operations.

Technology initiatives for the autonomous guidance, navigation, and control of single and multiple satellites

NASA Astrophysics Data System (ADS)

Croft, John; Deily, John; Hartman, Kathy; Weidow, David

1998-01-01

In the twenty-first century, NASA envisions frequent low-cost missions to explore the solar system, observe the universe, and study our planet. To realize NASA's goal, the Guidance, Navigation, and Control Center (GNCC) at the Goddard Space Flight Center sponsors technology programs that enhance spacecraft performance, streamline processes and ultimately enable cheaper science. Our technology programs encompass control system architectures, sensor and actuator components, electronic systems, design and development of algorithms, embedded systems and space vehicle autonomy. Through collaboration with government, universities, non-profit organizations, and industry, the GNCC incrementally develops key technologies that conquer NASA's challenges. This paper presents an overview of several innovative technology initiatives for the autonomous guidance, navigation, and control (GN&C) of satellites.

Cognitive Navigation: Toward a Biological Basis for Instructional Design.

ERIC Educational Resources Information Center

Tripp, Steven

2001-01-01

Discusses cognitive navigation, cognitive maps and online learning, and the role of the hippocampus in navigation. Topics include brain research in animal and human studies; types of memory; human navigation, including land navigation and information navigation; instructional strategies; tree maps of curriculum structure; cognitive complexity; and…

Intelligent single switch wheelchair navigation.

PubMed

Ka, Hyun W; Simpson, Richard; Chung, Younghyun

2012-11-01

We have developed an intelligent single switch scanning interface and wheelchair navigation assistance system, called intelligent single switch wheelchair navigation (ISSWN), to improve driving safety, comfort and efficiency for individuals who rely on single switch scanning as a control method. ISSWN combines a standard powered wheelchair with a laser rangefinder, a single switch scanning interface and a computer. It provides the user with context sensitive and task specific scanning options that reduce driving effort based on an interpretation of sensor data together with user input. Trials performed by 9 able-bodied participants showed that the system significantly improved driving safety and efficiency in a navigation task by significantly reducing the number of switch presses to 43.5% of traditional single switch wheelchair navigation (p < 0.001). All participants made a significant improvement (39.1%; p < 0.001) in completion time after only two trials.

Autonomous navigation using lunar beacons

NASA Technical Reports Server (NTRS)

Khatib, A. R.; Ellis, J.; French, J.; Null, G.; Yunck, T.; Wu, S.

1983-01-01

The concept of using lunar beacon signal transmission for on-board navigation for earth satellites and near-earth spacecraft is described. The system would require powerful transmitters on the earth-side of the moon's surface and black box receivers with antennae and microprocessors placed on board spacecraft for autonomous navigation. Spacecraft navigation requires three position and three velocity elements to establish location coordinates. Two beacons could be soft-landed on the lunar surface at the limits of allowable separation and each would transmit a wide-beam signal with cones reaching GEO heights and be strong enough to be received by small antennae in near-earth orbit. The black box processor would perform on-board computation with one-way Doppler/range data and dynamical models. Alternatively, GEO satellites such as the GPS or TDRSS spacecraft can be used with interferometric techniques to provide decimeter-level accuracy for aircraft navigation.

Lunar rover navigation concepts

NASA Astrophysics Data System (ADS)

Burke, James D.

1993-01-01

With regard to the navigation of mobile lunar vehicles on the surface, candidate techniques are reviewed and progress of simulations and experiments made up to now are described. Progress that can be made through precursor investigations on Earth is considered. In the early seventies the problem was examined in a series of relevant tests made in the California desert. Meanwhile, Apollo rovers made short exploratory sorties and robotic Lunokhods traveled over modest distances on the Moon. In these early missions some of the required methods were demonstrated. The navigation problem for a lunar traverse can be viewed in three parts: to determine the starting point with enough accuracy to enable the desired mission; to determine the event sequence required to reach the site of each traverse objective; and to redetermine actual positions enroute. The navigator's first tool is a map made from overhead imagery. The Moon was almost completely photographed at moderate resolution by spacecraft launched in the sixties, but that data set provides imprecise topographic and selenodetic information. Therefore, more advanced orbital missions are now proposed as part of a resumed lunar exploration program. With the mapping coverage expected from such orbiters, it will be possible to use a combination of visual landmark navigation and external radio and optical references (Earth and Sun) to achieve accurate surface navigation almost everywhere on the near side of the Moon. On the far side and in permanently dark polar areas, there are interesting exploration targets where additional techniques will have to be used.

Navigation strategy training using virtual reality in six chronic stroke patients: A novel and explorative approach to the rehabilitation of navigation impairment.

PubMed

Claessen, Michiel H G; van der Ham, Ineke J M; Jagersma, Elbrich; Visser-Meily, Johanna M A

2016-10-01

Recent studies have shown that navigation impairment is a common complaint after brain injury. Effective training programmes aiming to improve navigation ability in neurological patients are, however, scarce. The few reported programmes are merely focused on recalling specific routes rather than encouraging brain-damaged patients to use an alternative navigation strategy, applicable to any route. Our aim was therefore to investigate the feasibility of a (virtual reality) navigation training as a tool to instruct chronic stroke patients to adopt an alternative navigation strategy. Navigation ability was systematically assessed before the training. The training approach was then determined based on the individual pattern of navigation deficits of each patient. The use of virtual reality in the navigation strategy training in six middle-aged stroke patients was found to be highly feasible. Furthermore, five patients learned to (partially) apply an alternative navigation strategy in the virtual environment, suggesting that navigation strategies are mouldable rather than static. In the evaluation of their training experiences, the patients judged the training as valuable and proposed some suggestions for further improvement. The notion that the navigation strategy people use can be influenced after a short training procedure is a novel finding and initiates a direction for future studies.

BOREAS Level-0 C-130 Navigation Data

NASA Technical Reports Server (NTRS)

Strub, Richard; Newcomer, Jeffrey A.; Domingues, Roseanne; Hall, Forrest G. (Editor)

2000-01-01

The level-0 C-130 navigation data files contain aircraft attitude and position information acquired during the digital image and photographic data collection missions over the BOReal Ecosystem-Atmosphere Study (BOREAS) study areas. Various portions of the navigation data were collected at 1, 10, and 30 Hz. The level-0 C-130 navigation data collected for BOREAS in 1994 were improved over previous years in that the C-130 onboard navigation system was upgraded to output inertial navigation parameters every 1/30th of a second (i.e., 30 Hz). This upgrade was encouraged by users of the aircraft scanner data with the hope of improving the relative geometric positioning of the collected images.

Beacons for supporting lunar landing navigation

NASA Astrophysics Data System (ADS)

Theil, Stephan; Bora, Leonardo

2017-03-01

Current and future planetary exploration missions involve a landing on the target celestial body. Almost all of these landing missions are currently relying on a combination of inertial and optical sensor measurements to determine the current flight state with respect to the target body and the desired landing site. As soon as an infrastructure at the landing site exists, the requirements as well as conditions change for vehicles landing close to this existing infrastructure. This paper investigates the options for ground-based infrastructure supporting the onboard navigation system and analyzes the impact on the achievable navigation accuracy. For that purpose, the paper starts with an existing navigation architecture based on optical navigation and extends it with measurements to support navigation with ground infrastructure. A scenario of lunar landing is simulated and the provided functions of the ground infrastructure as well as the location with respect to the landing site are evaluated. The results are analyzed and discussed.

Deep space navigation systems and operations

NASA Technical Reports Server (NTRS)

Jordan, J. F.

1981-01-01

The history of the deep space navigation system developed by NASA is outlined. Its application to Mariner, Viking and Pioneer missions is reviewed. Voyager navigation results for Jupiter and Saturn are commented on and velocity correction in relation to fuel expenditure and computer time are discussed. The navigation requirements of the Gahleo and Venus orbiting imaging radar (VOIR) missions are assessed. The measurement and data processing systems are described.

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 to...

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 to...

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 to...

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 to...

Sea turtles: navigating with magnetism.

PubMed

Lohmann, Kenneth J

2007-02-06

Young sea turtles use the Earth's magnetic field as a source of navigational information during their epic transoceanic migrations and while homing. A new study using satellite telemetry has now demonstrated for the first time that adult turtles also navigate using the Earth's magnetic field.

SLS Model Based Design: A Navigation Perspective

NASA Technical Reports Server (NTRS)

Oliver, T. Emerson; Anzalone, Evan; Park, Thomas; Geohagan, Kevin

2018-01-01

The SLS Program has implemented a Model-based Design (MBD) and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team is responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1B design, the additional GPS Receiver hardware model is managed as a DMM at the vehicle design level. This paper describes the models, and discusses the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the navigation components.

Wearable Virtual White Cane Network for navigating people with visual impairment.

PubMed

Gao, Yabiao; Chandrawanshi, Rahul; Nau, Amy C; Tse, Zion Tsz Ho

2015-09-01

Navigating the world with visual impairments presents inconveniences and safety concerns. Although a traditional white cane is the most commonly used mobility aid due to its low cost and acceptable functionality, electronic traveling aids can provide more functionality as well as additional benefits. The Wearable Virtual Cane Network is an electronic traveling aid that utilizes ultrasound sonar technology to scan the surrounding environment for spatial information. The Wearable Virtual Cane Network is composed of four sensing nodes: one on each of the user's wrists, one on the waist, and one on the ankle. The Wearable Virtual Cane Network employs vibration and sound to communicate object proximity to the user. While conventional navigation devices are typically hand-held and bulky, the hands-free design of our prototype allows the user to perform other tasks while using the Wearable Virtual Cane Network. When the Wearable Virtual Cane Network prototype was tested for distance resolution and range detection limits at various displacements and compared with a traditional white cane, all participants performed significantly above the control bar (p < 4.3 × 10(-5), standard t-test) in distance estimation. Each sensor unit can detect an object with a surface area as small as 1 cm(2) (1 cm × 1 cm) located 70 cm away. Our results showed that the walking speed for an obstacle course was increased by 23% on average when subjects used the Wearable Virtual Cane Network rather than the white cane. The obstacle course experiment also shows that the use of the white cane in combination with the Wearable Virtual Cane Network can significantly improve navigation over using either the white cane or the Wearable Virtual Cane Network alone (p < 0.05, paired t-test). © IMechE 2015.

Optical navigation during the Voyager Neptune encounter

NASA Technical Reports Server (NTRS)

Riedel, J. E.; Owen, W. M., Jr.; Stuve, J. A.; Synnott, S. P.; Vaughan, R. M.

1990-01-01

Optical navigation techniques were required to successfully complete the planetary exploration phase of the NASA deep-space Voyager mission. The last of Voyager's planetary encounters, with Neptune, posed unique problems from an optical navigation standpoint. In this paper we briefly review general aspects of the optical navigation process as practiced during the Voyager mission, and discuss in detail particular features of the Neptune encounter which affected optical navigation. New approaches to the centerfinding problem were developed for both stars and extended bodies, and these are described. Results of the optical navigation data analysis are presented, as well as a description of the optical orbit determination system and results of its use during encounter. Partially as a result of the optical navigation processing, results of scientific significance were obtained. These results include the discovery and orbit determination of several new satellites of Neptune and the determination of the size of Triton, Neptune's largest moon.

Collective navigation of complex networks: Participatory greedy routing.

PubMed

Kleineberg, Kaj-Kolja; Helbing, Dirk

2017-06-06

Many networks are used to transfer information or goods, in other words, they are navigated. The larger the network, the more difficult it is to navigate efficiently. Indeed, information routing in the Internet faces serious scalability problems due to its rapid growth, recently accelerated by the rise of the Internet of Things. Large networks like the Internet can be navigated efficiently if nodes, or agents, actively forward information based on hidden maps underlying these systems. However, in reality most agents will deny to forward messages, which has a cost, and navigation is impossible. Can we design appropriate incentives that lead to participation and global navigability? Here, we present an evolutionary game where agents share the value generated by successful delivery of information or goods. We show that global navigability can emerge, but its complete breakdown is possible as well. Furthermore, we show that the system tends to self-organize into local clusters of agents who participate in the navigation. This organizational principle can be exploited to favor the emergence of global navigability in the system.

Navigating the fifth dimension: new concepts in interactive multimodality and multidimensional image navigation

NASA Astrophysics Data System (ADS)

Ratib, Osman; Rosset, Antoine; Dahlbom, Magnus; Czernin, Johannes

2005-04-01

Display and interpretation of multi dimensional data obtained from the combination of 3D data acquired from different modalities (such as PET-CT) require complex software tools allowing the user to navigate and modify the different image parameters. With faster scanners it is now possible to acquire dynamic images of a beating heart or the transit of a contrast agent adding a fifth dimension to the data. We developed a DICOM-compliant software for real time navigation in very large sets of 5 dimensional data based on an intuitive multidimensional jog-wheel widely used by the video-editing industry. The software, provided under open source licensing, allows interactive, single-handed, navigation through 3D images while adjusting blending of image modalities, image contrast and intensity and the rate of cine display of dynamic images. In this study we focused our effort on the user interface and means for interactively navigating in these large data sets while easily and rapidly changing multiple parameters such as image position, contrast, intensity, blending of colors, magnification etc. Conventional mouse-driven user interface requiring the user to manipulate cursors and sliders on the screen are too cumbersome and slow. We evaluated several hardware devices and identified a category of multipurpose jogwheel device that is used in the video-editing industry that is particularly suitable for rapidly navigating in five dimensions while adjusting several display parameters interactively. The application of this tool will be demonstrated in cardiac PET-CT imaging and functional cardiac MRI studies.

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.

Stellar Inertial Navigation Workstation

NASA Technical Reports Server (NTRS)

Johnson, W.; Johnson, B.; Swaminathan, N.

1989-01-01

Software and hardware assembled to support specific engineering activities. Stellar Inertial Navigation Workstation (SINW) is integrated computer workstation providing systems and engineering support functions for Space Shuttle guidance and navigation-system logistics, repair, and procurement activities. Consists of personal-computer hardware, packaged software, and custom software integrated together into user-friendly, menu-driven system. Designed to operate on IBM PC XT. Applied in business and industry to develop similar workstations.

Lay navigator model for impacting cancer health disparities.

PubMed

Meade, Cathy D; Wells, Kristen J; Arevalo, Mariana; Calcano, Ercilia R; Rivera, Marlene; Sarmiento, Yolanda; Freeman, Harold P; Roetzheim, Richard G

2014-09-01

This paper recounts experiences, challenges, and lessons learned when implementing a lay patient navigator program to improve cancer care among medically underserved patients who presented in a primary care clinic with a breast or colorectal cancer abnormality. The program employed five lay navigators to navigate 588 patients. Central programmatic elements were the following: (1) use of bilingual lay navigators with familiarity of communities they served; (2) provision of training, education, and supportive activities; (3) multidisciplinary clinical oversight that factored in caseload intensity; and (4) well-developed partnerships with community clinics and social service entities. Deconstruction of healthcare system information was fundamental to navigation processes. We conclude that a lay model of navigation is well suited to assist patients through complex healthcare systems; however, a stepped care model that includes both lay and professional navigation may be optimal to help patients across the entire continuum.

Lay Navigator Model for Impacting Cancer Health Disparities

PubMed Central

Meade, Cathy D.; Wells, Kristen J.; Arevalo, Mariana; Calcano, Ercilia R.; Rivera, Marlene; Sarmiento, Yolanda; Freeman, Harold P; Roetzheim, Richard G.

2014-01-01

This paper recounts experiences, challenges, and lessons learned when implementing a lay patient navigator program to improve cancer care among medically underserved patients who presented in a primary care clinic with a breast or colorectal cancer abnormality. The program employed five lay navigators to navigate 588 patients. Central programmatic elements were: 1) use of bilingual lay navigators with familiarity of communities they served; 2) provision of training, education and supportive activities; 3) multidisciplinary clinical oversight that factored in caseload intensity; and 4) well-developed partnerships with community clinics and social service entities. Deconstruction of health care system information was fundamental to navigation processes. We conclude that a lay model of navigation is well suited to assist patients through complex health care systems; however, a stepped care model that includes both lay and professional navigation may be optimal to help patients across the entire continuum. PMID:24683043

Optical Navigation Image of Ganymede

NASA Technical Reports Server (NTRS)

1996-01-01

NASA's Galileo spacecraft, now in orbit around Jupiter, returned this optical navigation image June 3, 1996, showing that the spacecraft is accurately targeted for its first flyby of the giant moon Ganymede on June 27. The missing data in the frame is the result of a special editing feature recently added to the spacecraft's computer to transmit navigation images more quickly. This is first in a series of optical navigation frames, highly edited onboard the spacecraft, that will be used to fine-tune the spacecraft's trajectory as Galileo approaches Ganymede. The image, used for navigation purposes only, is the product of new computer processing capabilities on the spacecraft that allow Galileo to send back only the information required to show the spacecraft is properly targeted and that Ganymede is where navigators calculate it to be. 'This navigation image is totally different from the pictures we'll be taking for scientific study of Ganymede when we get close to it later this month,' said Galileo Project Scientist Dr. Torrence Johnson. On June 27, Galileo will fly just 844 kilometers (524 miles) above Ganymede and return the most detailed, full-frame, high-resolution images and other measurements of the satellite ever obtained. Icy Ganymede is the largest moon in the solar system and three-quarters the size of Mars. It is one of the four large Jovian moons that are special targets of study for the Galileo mission. Of the more than 5 million bits contained in a single image, Galileo performed on-board editing to send back a mere 24,000 bits containing the essential information needed to assure proper targeting. Only the light-to-dark transitions of the crescent Ganymede and reference star locations were transmitted to Earth. The navigation image was taken from a distance of 9.8 million kilometers (6.1 million miles). On June 27th, the spacecraft will be 10,000 times closer to Ganymede.

Optical surgical navigation system causes pulse oximeter malfunction.

PubMed

Satoh, Masaaki; Hara, Tetsuhito; Tamai, Kenji; Shiba, Juntaro; Hotta, Kunihisa; Takeuchi, Mamoru; Watanabe, Eiju

2015-01-01

An optical surgical navigation system is used as a navigator to facilitate surgical approaches, and pulse oximeters provide valuable information for anesthetic management. However, saw-tooth waves on the monitor of a pulse oximeter and the inability of the pulse oximeter to accurately record the saturation of a percutaneous artery were observed when a surgeon started an optical navigation system. The current case is thought to be the first report of this navigation system interfering with pulse oximetry. The causes of pulse jamming and how to manage an optical navigation system are discussed.

Relative navigation requirements for automatic rendezvous and capture systems

NASA Technical Reports Server (NTRS)

Kachmar, Peter M.; Polutchko, Robert J.; Chu, William; Montez, Moises

1991-01-01

This paper will discuss in detail the relative navigation system requirements and sensor trade-offs for Automatic Rendezvous and Capture. Rendezvous navigation filter development will be discussed in the context of navigation performance requirements for a 'Phase One' AR&C system capability. Navigation system architectures and the resulting relative navigation performance for both cooperative and uncooperative target vehicles will be assessed. Relative navigation performance using rendezvous radar, star tracker, radiometric, laser and GPS navigation sensors during appropriate phases of the trajectory will be presented. The effect of relative navigation performance on the Integrated AR&C system performance will be addressed. Linear covariance and deterministic simulation results will be used. Evaluation of relative navigation and IGN&C system performance for several representative relative approach profiles will be presented in order to demonstrate the full range of system capabilities. A summary of the sensor requirements and recommendations for AR&C system capabilities for several programs requiring AR&C will be presented.

33 CFR 117.458 - Inner Harbor Navigation Canal, New Orleans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inner Harbor Navigation Canal, New Orleans. 117.458 Section 117.458 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Harbor Navigation Canal, New Orleans. (a) The draws of the SR 46 (St. Claude Avenue) bridge, mile 0.5...

The JPL roadmap for Deep Space navigation

NASA Technical Reports Server (NTRS)

Martin-Mur, Tomas J.; Abraham, Douglas S.; Berry, David; Bhaskaran, Shyam; Cesarone, Robert J.; Wood, Lincoln

2006-01-01

This paper reviews the tentative set of deep space missions that will be supported by NASA's Deep Space Mission System in the next twenty-five years, and extracts the driving set of navigation capabilities that these missions will require. There will be many challenges including the support of new mission navigation approaches such as formation flying and rendezvous in deep space, low-energy and low-thrust orbit transfers, precise landing and ascent vehicles, and autonomous navigation. Innovative strategies and approaches will be needed to develop and field advanced navigation capabilities.

Data management of Shuttle radiofrequency navigation aids

NASA Technical Reports Server (NTRS)

Stokes, R. E.; Presser, P.

1982-01-01

It is noted that the Shuttle navigation system employs redundant tactical air navigation (tacan) and microwave scanning beam landing system (MSBLS) equipment for use in navigation during descent from altitudes of about 150,000 feet through rollout. Attention is given here to the multiple tacan and MSBLS units (three each) that were placed onboard to provide the necessary protection in the event of possible failures. The goals, features, approach, and performance of onboard software required to manage multiple tacan MSBLS units and to provide the corresponding data for navigation processing are described.

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.

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.

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…

Air Navigation. Aerospace Education II.

ERIC Educational Resources Information Center

Cox, Rodney V., Jr.

This revised textbook, published for the Air Force ROTC program, contains a discussion of basic and essential understandings about air navigation. The first part of the book describes maps, air navigation charts, flight planning, and pilotage preflight. Basic differences between ground maps and air charts are described and the methods of…

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…

Private Graphs - Access Rights on Graphs for Seamless Navigation

NASA Astrophysics Data System (ADS)

Dorner, W.; Hau, F.; Pagany, R.

2016-06-01

After the success of GNSS (Global Navigational Satellite Systems) and navigation services for public streets, indoor seems to be the next big development in navigational services, relying on RTLS - Real Time Locating Services (e.g. WIFI) and allowing seamless navigation. In contrast to navigation and routing services on public streets, seamless navigation will cause an additional challenge: how to make routing data accessible to defined users or restrict access rights for defined areas or only to parts of the graph to a defined user group? The paper will present case studies and data from literature, where seamless and especially indoor navigation solutions are presented (hospitals, industrial complexes, building sites), but the problem of restricted access rights was only touched from a real world, but not a technical perspective. The analysis of case studies will show, that the objective of navigation and the different target groups for navigation solutions will demand well defined access rights and require solutions, how to make only parts of a graph to a user or application available to solve a navigational task. The paper will therefore introduce the concept of private graphs, which is defined as a graph for navigational purposes covering the street, road or floor network of an area behind a public street and suggest different approaches how to make graph data for navigational purposes available considering access rights and data protection, privacy and security issues as well.

Academic health sciences library Website navigation: an analysis of forty-one Websites and their navigation tools.

PubMed

Brower, Stewart M

2004-10-01

The analysis included forty-one academic health sciences library (HSL) Websites as captured in the first two weeks of January 2001. Home pages and persistent navigational tools (PNTs) were analyzed for layout, technology, and links, and other general site metrics were taken. Websites were selected based on rank in the National Network of Libraries of Medicine, with regional and resource libraries given preference on the basis that these libraries are recognized as leaders in their regions and would be the most reasonable source of standards for best practice. A three-page evaluation tool was developed based on previous similar studies. All forty-one sites were evaluated in four specific areas: library general information, Website aids and tools, library services, and electronic resources. Metrics taken for electronic resources included orientation of bibliographic databases alphabetically by title or by subject area and with links to specifically named databases. Based on the results, a formula for determining obligatory links was developed, listing items that should appear on all academic HSL Web home pages and PNTs. These obligatory links demonstrate a series of best practices that may be followed in the design and construction of academic HSL Websites.

Robot navigation research using the HERMIES mobile robot

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnett, D.L.

1989-01-01

In recent years robot navigation has attracted much attention from researchers around the world. Not only are theoretical studies being simulated on sophisticated computers, but many mobile robots are now used as test vehicles for these theoretical studies. Various algorithms have been perfected for navigation in a known static environment; but navigation in an unknown and dynamic environment poses a much more challenging problem for researchers. Many different methodologies have been developed for autonomous robot navigation, but each methodology is usually restricted to a particular type of environment. One important research focus of the Center for Engineering Systems Advanced researchmore » (CESAR) at Oak Ridge National Laboratory, is autonomous navigation in unknown and dynamic environments using the series of HERMIES mobile robots. The research uses an expert system for high-level planning interfaced with C-coded routines for implementing the plans, and for quick processing of data requested by the expert system. In using this approach, the navigation is not restricted to one methodology since the expert system can activate a rule module for the methodology best suited for the current situation. Rule modules can be added the rule base as they are developed and tested. Modules are being developed or enhanced for navigating from a map, searching for a target, exploring, artificial potential-field navigation, navigation using edge-detection, etc. This paper will report on the various rule modules and methods of navigation in use, or under development at CESAR, using the HERMIES-IIB robot as a testbed. 13 refs., 5 figs., 1 tab.« less

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.

INTEGRATED INS/GPS NAVIGATION FROM A POPULAR PERSPECTIVE

DOT National Transportation Integrated Search

2002-02-13

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. Relat...

Outer planet probe navigation. [considering Pioneer space missions

NASA Technical Reports Server (NTRS)

Friedman, L.

1974-01-01

A series of navigation studies in conjunction with outer planet Pioneer missions are reformed to determine navigation requirements and measurement systems in order to target probes. Some particular cases are established where optical navigation is important and some cases where radio alone navigation is suffucient. Considered are a direct Saturn mission, a Saturn Uranus mission, a Jupiter Uranus mission, and a Titan probe mission.

Multiple beacons for supporting lunar landing navigation

NASA Astrophysics Data System (ADS)

Theil, Stephan; Bora, Leonardo

2018-02-01

The exploration and potential future exploitation of solar system bodies requires technologies for precise and safe landings. Current navigation systems for landing probes are relying on a combination of inertial and optical sensor measurements to determine the current flight state with respect to the target body and the desired landing site. With a future transition from single exploration missions to more frequent first exploration and then exploitation missions, the implementation and operation of these missions changes, since it can be expected that a ground infrastructure on the target body is available in the vicinity of the landing site. In a previous paper, the impact of a single ground-based beacon on the navigation performance was investigated depending on the type of radiometric measurements and on the location of the beacon with respect to the landing site. This paper extends this investigation on options for ground-based multiple beacons supporting the on-board navigation system. It analyzes the impact on the achievable navigation accuracy. For that purpose, the paper introduces briefly the existing navigation architecture based on optical navigation and its extension with radiometric measurements. The same scenario of lunar landing as in the previous paper is simulated. The results are analyzed and discussed. They show a single beacon at a large distance along the landing trajectory and multiple beacons close to the landing site can improve the navigation performance. The results show how large the landing area can be increased where a sufficient navigation performance is achieved using the beacons.

Defence electronics industry profile, 1990-1991

NASA Astrophysics Data System (ADS)

The defense electronics industry profiled in this review comprises an estimated 150 Canadian companies that develop, manufacture, and repair radio and communications equipment, radars for surveillance and navigation, air traffic control systems, acoustic and infrared sensors, computers for navigation and fire control, signal processors and display units, special-purpose electronic components, and systems engineering and associated software. Canadian defense electronics companies generally serve market niches and end users of their products are limited to the military, government agencies, or commercial airlines. Geographically, the industry is concentrated in Ontario and Quebec, where about 91 percent of the industry's production and employment is found. In 1989, the estimated revenue of the industry was $2.36 billion, and exports totalled an estimated $1.4 billion. Strengths and weaknesses of the industry are discussed in terms of such factors as the relatively small size of Canadian companies, the ability of Canadian firms to access research and development opportunities and export markets in the United States, the dependence on foreign-made components, and international competition.

Autonomous precision landing using terrain-following navigation

NASA Technical Reports Server (NTRS)

Vaughan, R. M.; Gaskell, R. W.; Halamek, P.; Klumpp, A. R.; Synnott, S. P.

1991-01-01

Terrain-following navigation studies that have been done over the past two years in the navigation system section at JPL are described. A descent to Mars scenario based on Mars Rover and Sample Return mission profiles is described, and navigation and image processing issues pertaining to descent phases where landmark picture can be obtained are examined. A covariance analysis is performed to verify that landmark measurements from a terrain-following navigation system can satisfy precision landing requirements. Image processing problems involving known landmarks in actual pictures are considered. Mission design alternatives that can alleviate some of these problems are suggested.

Remote magnetic navigation vs. manual navigation for ablation of ventricular tachycardia: a meta-analysis.

PubMed

Wu, Y; Li, K-L; Zheng, J; Zhang, C-Y; Liu, X-Y; Cui, Z-M; Yu, Z-M; Wang, R-X; Wang, W

2015-09-01

The purpose of this study was to prospectively evaluate the efficacy and safety of remote magnetic navigation (RMN) in comparison with manual catheter navigation (MCN) in performing ventricular tachycardia ablation. An electronic search was performed using PubMed (1948-2013) and EMBASE (1974-2013) studies comparing RMN with MCN which were published prior to 31 December 2013. Outcomes of interest were as follows: acute success, recurrence rate, complications, total procedure and fluoroscopic times. Standard mean difference (SMD) and its 95 % confidence interval (CI) were used for continuous outcomes; odds ratios (OR) were reported for dichotomous variables. Four non-randomised studies, including a total of 328 patients, were identified. RMN was deployed in 191 patients. Acute success and long-term freedom from arrhythmias were not significantly different between the RMN and control groups (OR 1.845, 95 % CI 0.731-4.659, p = 0.195 and OR 0.676, 95 % CI 0.383-1.194, p = 0.177, respectively). RMN was associated with less peri-procedural complications (OR 0.279, 95 % CI 0.092-0.843, p = 0.024). Shorter procedural and fluoroscopy times were achieved (95 % CI -0.487 to -0.035, p = 0.024 and 95 % CI -1.467 to -0.984, p<0.001, respectively). The acute and long-term success rates for VT ablation are equal between RMN and MCN, whereas the RMN-guided procedure can be performed with a lower complication rate and less procedural and fluoroscopic times. More prospective randomised trials will be needed to better evaluate the superior role of RMN for catheter ablation of ventricular tachycardia.

Integrated polarization-dependent sensor for autonomous navigation

NASA Astrophysics Data System (ADS)

Liu, Ze; Zhang, Ran; Wang, Zhiwen; Guan, Le; Li, Bin; Chu, Jinkui

2015-01-01

Based on the navigation strategy of insects utilizing the polarized skylight, an integrated polarization-dependent sensor for autonomous navigation is presented. The navigation sensor has the features of compact structure, high precision, strong robustness, and a simple manufacture technique. The sensor is composed by integrating a complementary-metal-oxide-semiconductor sensor with a multiorientation nanowire grid polarizer. By nanoimprint lithography, the multiorientation nanowire polarizer is fabricated in one step and the alignment error is eliminated. The statistical theory is added to the interval-division algorithm to calculate the polarization angle of the incident light. The laboratory and outdoor tests for the navigation sensor are implemented and the errors of the measured angle are ±0.02 deg and ±1.3 deg, respectively. The results show that the proposed sensor has potential for application in autonomous navigation.

A novel platform for electromagnetic navigated ultrasound bronchoscopy (EBUS).

PubMed

Sorger, Hanne; Hofstad, Erlend Fagertun; Amundsen, Tore; Langø, Thomas; Leira, Håkon Olav

2016-08-01

Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) of mediastinal lymph nodes is essential for lung cancer staging and distinction between curative and palliative treatment. Precise sampling is crucial. Navigation and multimodal imaging may improve the efficiency of EBUS-TBNA. We demonstrate a novel EBUS-TBNA navigation system in a dedicated airway phantom. Using a convex probe EBUS bronchoscope (CP-EBUS) with an integrated sensor for electromagnetic (EM) position tracking, we performed navigated CP-EBUS in a phantom. Preoperative computed tomography (CT) and real-time ultrasound (US) images were integrated into a navigation platform for EM navigated bronchoscopy. The coordinates of targets in CT and US volumes were registered in the navigation system, and the position deviation was calculated. The system visualized all tumor models and displayed their fused CT and US images in correct positions in the navigation system. Navigating the EBUS bronchoscope was fast and easy. Mean error observed between US and CT positions for 11 target lesions (37 measurements) was [Formula: see text] mm, maximum error was 5.9 mm. The feasibility of our novel navigated CP-EBUS system was successfully demonstrated. An EBUS navigation system is needed to meet future requirements of precise mediastinal lymph node mapping, and provides new opportunities for procedure documentation in EBUS-TBNA.

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 under...

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 under...

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 under...

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 under...

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 under...

Comparative advantage between traditional and smart navigation systems

NASA Astrophysics Data System (ADS)

Shin, Jeongkyu; Kim, Pan-Jun; Kim, Seunghwan

2013-03-01

The smart navigation system that refers to real-time traffic data is believed to be superior to traditional navigation systems. To verify this belief, we created an agent-based traffic model and examined the effect of changing market share of the traditional shortest-travel-time algorithm based navigation and the smart navigation system. We tested our model on the grid and actual metropolitan road network structures. The result reveals that the traditional navigation system have better performance than the smart one as the market share of the smart navigation system exceeds a critical value, which is contrary to conventional expectation. We suggest that the superiority inversion between agent groups is strongly related to the traffic weight function form, and is general. We also found that the relationship of market share, traffic flow density and travel time is determined by the combination of congestion avoidance behavior of the smartly navigated agents and the inefficiency of shortest-travel-time based navigated agents. Our results can be interpreted with the minority game and extended to the diverse topics of opinion dynamics. This work was supported by the Original Technology Research Program for Brain Science through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology(No. 2010-0018847).

33 CFR 165.827 - Regulated Navigation Area; Galveston Channel, TX.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Regulated Navigation Area... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Eighth Coast Guard District § 165.827...

33 CFR 165.827 - Regulated Navigation Area; Galveston Channel, TX.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Regulated Navigation Area... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Eighth Coast Guard District § 165.827...

Advanced Navigation Strategies For Asteroid Sample Return Missions

NASA Technical Reports Server (NTRS)

Getzandanner, K.; Bauman, J.; Williams, B.; Carpenter, J.

2010-01-01

Flyby and rendezvous missions to asteroids have been accomplished using navigation techniques derived from experience gained in planetary exploration. This paper presents analysis of advanced navigation techniques required to meet unique challenges for precision navigation to acquire a sample from an asteroid and return it to Earth. These techniques rely on tracking data types such as spacecraft-based laser ranging and optical landmark tracking in addition to the traditional Earth-based Deep Space Network radio metric tracking. A systematic study of navigation strategy, including the navigation event timeline and reduction in spacecraft-asteroid relative errors, has been performed using simulation and covariance analysis on a representative mission.

The role of the hippocampus in navigation is memory

PubMed Central

2017-01-01

There is considerable research on the neurobiological mechanisms within the hippocampal system that support spatial navigation. In this article I review the literature on navigational strategies in humans and animals, observations on hippocampal function in navigation, and studies of hippocampal neural activity in animals and humans performing different navigational tasks and tests of memory. Whereas the hippocampus is essential to spatial navigation via a cognitive map, its role derives from the relational organization and flexibility of cognitive maps and not from a selective role in the spatial domain. Correspondingly, hippocampal networks map multiple navigational strategies, as well as other spatial and nonspatial memories and knowledge domains that share an emphasis on relational organization. These observations suggest that the hippocampal system is not dedicated to spatial cognition and navigation, but organizes experiences in memory, for which spatial mapping and navigation are both a metaphor for and a prominent application of relational memory organization. PMID:28148640

A Navigation Compendium. Revised Edition.

ERIC Educational Resources Information Center

Naval Training Command, Pensacola, FL.

This unit of instruction was prepared for use in navigation study at the Officer Candidate School, the various Naval ROTC Units, and within the fleet. It is considered a naval text. It covers a wide and expanding subject area with brevity. Basic and elementary navigational terms and instruments are presented and described. The use of charts and…

Intelligent navigation to improve obstetrical sonography.

PubMed

Yeo, Lami; Romero, Roberto

2016-04-01

'Manual navigation' by the operator is the standard method used to obtain information from two-dimensional and volumetric sonography. Two-dimensional sonography is highly operator dependent and requires extensive training and expertise to assess fetal anatomy properly. Most of the sonographic examination time is devoted to acquisition of images, while 'retrieval' and display of diagnostic planes occurs rapidly (essentially instantaneously). In contrast, volumetric sonography has a rapid acquisition phase, but the retrieval and display of relevant diagnostic planes is often time-consuming, tedious and challenging. We propose the term 'intelligent navigation' to refer to a new method of interrogation of a volume dataset whereby identification and selection of key anatomical landmarks allow the system to: 1) generate a geometrical reconstruction of the organ of interest; and 2) automatically navigate, find, extract and display specific diagnostic planes. This is accomplished using operator-independent algorithms that are both predictable and adaptive. Virtual Intelligent Sonographer Assistance (VIS-Assistance®) is a tool that allows operator-independent sonographic navigation and exploration of the surrounding structures in previously identified diagnostic planes. The advantage of intelligent (over manual) navigation in volumetric sonography is the short time required for both acquisition and retrieval and display of diagnostic planes. Intelligent navigation technology automatically realigns the volume, and reorients and standardizes the anatomical position, so that the fetus and the diagnostic planes are consistently displayed in the same manner each time, regardless of the fetal position or the initial orientation. Automatic labeling of anatomical structures, subject orientation and each of the diagnostic planes is also possible. Intelligent navigation technology can operate on conventional computers, and is not dependent on specific ultrasound platforms or on the

14 CFR 27.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flight and navigation instruments. 27.1303... navigation instruments. The following are the required flight and navigation instruments: (a) An airspeed indicator. (b) An altimeter. (c) A magnetic direction indicator. ...

14 CFR 27.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight and navigation instruments. 27.1303... navigation instruments. The following are the required flight and navigation instruments: (a) An airspeed indicator. (b) An altimeter. (c) A magnetic direction indicator. ...

46 CFR 112.43-7 - Navigating bridge distribution panel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Navigating bridge distribution panel. 112.43-7 Section... EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Lighting Systems § 112.43-7 Navigating bridge distribution... supplied from a distribution panel on the navigating bridge: (1) Navigation lights not supplied by the...

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 navigation...

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 navigation...

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 navigation...

46 CFR 112.43-7 - Navigating bridge distribution panel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Navigating bridge distribution panel. 112.43-7 Section... EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Lighting Systems § 112.43-7 Navigating bridge distribution... supplied from a distribution panel on the navigating bridge: (1) Navigation lights not supplied by the...

46 CFR 25.10-3 - Navigation light certification requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Navigation light certification requirements. 25.10-3... Navigation Lights § 25.10-3 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each navigation light must— (1) Meet the technical standards of the applicable...

46 CFR 25.10-3 - Navigation light certification requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 1 2014-10-01 2014-10-01 false Navigation light certification requirements. 25.10-3... Navigation Lights § 25.10-3 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each navigation light must— (1) Meet the technical standards of the applicable...

46 CFR 25.10-3 - Navigation light certification requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 1 2013-10-01 2013-10-01 false Navigation light certification requirements. 25.10-3... Navigation Lights § 25.10-3 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each navigation light must— (1) Meet the technical standards of the applicable...

46 CFR 25.10-3 - Navigation light certification requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 1 2012-10-01 2012-10-01 false Navigation light certification requirements. 25.10-3... Navigation Lights § 25.10-3 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each navigation light must— (1) Meet the technical standards of the applicable...

46 CFR 25.10-3 - Navigation light certification requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 1 2011-10-01 2011-10-01 false Navigation light certification requirements. 25.10-3... Navigation Lights § 25.10-3 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each navigation light must— (1) Meet the technical standards of the applicable...

33 CFR 401.97 - Closing procedures and ice navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Closing procedures and ice... Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel shall return downbound... nearest Seaway station. (f) Where ice conditions restrict navigation, (1) No upbound vessel that has a...

33 CFR 401.97 - Closing procedures and ice navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Closing procedures and ice... Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel shall return downbound... nearest Seaway station. (f) Where ice conditions restrict navigation, (1) No upbound vessel that has a...

33 CFR 401.97 - Closing procedures and ice navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Closing procedures and ice... Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel shall return downbound... nearest Seaway station. (f) Where ice conditions restrict navigation, (1) No upbound vessel that has a...

33 CFR 401.97 - Closing procedures and ice navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Closing procedures and ice... Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel shall return downbound... nearest Seaway station. (f) Where ice conditions restrict navigation, (1) No upbound vessel that has a...

33 CFR 401.97 - Closing procedures and ice navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Closing procedures and ice... Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel shall return downbound... nearest Seaway station. (f) Where ice conditions restrict navigation, (1) No upbound vessel that has a...

A Strapdown Interial Navigation System/Beidou/Doppler Velocity Log Integrated Navigation Algorithm Based on a Cubature Kalman Filter

PubMed Central

Gao, Wei; Zhang, Ya; Wang, Jianguo

2014-01-01

The integrated navigation system with strapdown inertial navigation system (SINS), Beidou (BD) receiver and Doppler velocity log (DVL) can be used in marine applications owing to the fact that the redundant and complementary information from different sensors can markedly improve the system accuracy. However, the existence of multisensor asynchrony will introduce errors into the system. In order to deal with the problem, conventionally the sampling interval is subdivided, which increases the computational complexity. In this paper, an innovative integrated navigation algorithm based on a Cubature Kalman filter (CKF) is proposed correspondingly. A nonlinear system model and observation model for the SINS/BD/DVL integrated system are established to more accurately describe the system. By taking multi-sensor asynchronization into account, a new sampling principle is proposed to make the best use of each sensor's information. Further, CKF is introduced in this new algorithm to enable the improvement of the filtering accuracy. The performance of this new algorithm has been examined through numerical simulations. The results have shown that the positional error can be effectively reduced with the new integrated navigation algorithm. Compared with the traditional algorithm based on EKF, the accuracy of the SINS/BD/DVL integrated navigation system is improved, making the proposed nonlinear integrated navigation algorithm feasible and efficient. PMID:24434842

Metrics for evaluating patient navigation during cancer diagnosis and treatment: crafting a policy-relevant research agenda for patient navigation in cancer care.

PubMed

Guadagnolo, B Ashleigh; Dohan, Daniel; Raich, Peter

2011-08-01

Racial and ethnic minorities as well as other vulnerable populations experience disparate cancer-related health outcomes. Patient navigation is an emerging health care delivery innovation that offers promise in improving quality of cancer care delivery to these patients who experience unique health-access barriers. Metrics are needed to evaluate whether patient navigation can improve quality of care delivery, health outcomes, and overall value in health care during diagnosis and treatment of cancer. Information regarding the current state of the science examining patient navigation interventions was gathered via search of the published scientific literature. A focus group of providers, patient navigators, and health-policy experts was convened as part of the Patient Navigation Leadership Summit sponsored by the American Cancer Society. Key metrics were identified for assessing the efficacy of patient navigation in cancer diagnosis and treatment. Patient navigation data exist for all stages of cancer care; however, the literature is more robust for its implementation during prevention, screening, and early diagnostic workup of cancer. Relatively fewer data are reported for outcomes and efficacy of patient navigation during cancer treatment. Metrics are proposed for a policy-relevant research agenda to evaluate the efficacy of patient navigation in cancer diagnosis and treatment. Patient navigation is understudied with respect to its use in cancer diagnosis and treatment. Core metrics are defined to evaluate its efficacy in improving outcomes and mitigating health-access barriers. Copyright © 2011 American Cancer Society.

Metrics for evaluating patient navigation during cancer diagnosis and treatment: crafting a policy-relevant research agenda for patient navigation in cancer care

PubMed Central

Guadagnolo, B. Ashleigh; Dohan, Daniel; Raich, Peter

2016-01-01

Background Racial and ethnic minorities as well as other vulnerable populations experience disparate cancer-related health outcomes. Patient navigation is an emerging health care delivery innovation that offers promise in improving quality of cancer care delivery to these patients who experience unique health access barriers. Metrics are needed to evaluate whether patient navigation can improve quality of care delivery, health outcomes, and overall value in health care during diagnosis and treatment of cancer. Methods Information regarding the current state of the science examining patient navigation interventions was gathered via search of the published scientific literature. A focus group of providers, patient navigators, and health policy experts was convened as part of the Patient Navigation Leadership Summit sponsored by the American Cancer Society. Key metrics were identified for assessing the efficacy of patient navigation in cancer diagnosis and treatment. Results Patient navigation data exists for all stages of cancer care; however, the literature is more robust for its implementation during prevention, screening, and early diagnostic work-up of cancer. Relatively fewer data are reported for outcomes and efficacy of patient navigation during cancer treatment. Metrics are proposed for a policy-relevant research agenda to evaluate the efficacy of patient navigation in cancer diagnosis and treatment. Conclusions Patient navigation is understudied with respect to its use in cancer diagnosis and treatment. Core metrics are defined to evaluate its efficacy in improving outcomes and mitigating health access barriers. PMID:21780091

Shape Perception and Navigation in Blind Adults

PubMed Central

Gori, Monica; Cappagli, Giulia; Baud-Bovy, Gabriel; Finocchietti, Sara

2017-01-01

Different sensory systems interact to generate a representation of space and to navigate. Vision plays a critical role in the representation of space development. During navigation, vision is integrated with auditory and mobility cues. In blind individuals, visual experience is not available and navigation therefore lacks this important sensory signal. In blind individuals, compensatory mechanisms can be adopted to improve spatial and navigation skills. On the other hand, the limitations of these compensatory mechanisms are not completely clear. Both enhanced and impaired reliance on auditory cues in blind individuals have been reported. Here, we develop a new paradigm to test both auditory perception and navigation skills in blind and sighted individuals and to investigate the effect that visual experience has on the ability to reproduce simple and complex paths. During the navigation task, early blind, late blind and sighted individuals were required first to listen to an audio shape and then to recognize and reproduce it by walking. After each audio shape was presented, a static sound was played and the participants were asked to reach it. Movements were recorded with a motion tracking system. Our results show three main impairments specific to early blind individuals. The first is the tendency to compress the shapes reproduced during navigation. The second is the difficulty to recognize complex audio stimuli, and finally, the third is the difficulty in reproducing the desired shape: early blind participants occasionally reported perceiving a square but they actually reproduced a circle during the navigation task. We discuss these results in terms of compromised spatial reference frames due to lack of visual input during the early period of development. PMID:28144226

An Empirical Comparison of Navigation Effect of Pull-Down Menu Style on The World Wide Web.

ERIC Educational Resources Information Center

Yu, Byeong-Min; Han, Sungwook

Effective navigation is becoming more and more critical to the success of electronic commerce (E-commerce). It remains a challenge for educational technologists and Web designers to develop Web systems that can help customers find products or services without experiencing disorientation problems and cognitive overload. Many E-commerce Web sites…

The University of Minnesota's Internet Gopher System: A Tool for Accessing Network-Based Electronic Information.

ERIC Educational Resources Information Center

Wiggins, Rich

1993-01-01

Describes the Gopher system developed at the University of Minnesota for accessing information on the Internet. Highlights include the need for navigation tools; Gopher clients; FTP (File Transfer Protocol); campuswide information systems; navigational enhancements; privacy and security issues; electronic publishing; multimedia; and future…

Indoor magnetic navigation for the blind.

PubMed

Riehle, Timothy H; Anderson, Shane M; Lichter, Patrick A; Giudice, Nicholas A; Sheikh, Suneel I; Knuesel, Robert J; Kollmann, Daniel T; Hedin, Daniel S

2012-01-01

Indoor navigation technology is needed to support seamless mobility for the visually impaired. This paper describes the construction of and evaluation of a navigation system that infers the users' location using only magnetic sensing. It is well known that the environments within steel frame structures are subject to significant magnetic distortions. Many of these distortions are persistent and have sufficient strength and spatial characteristics to allow their use as the basis for a location technology. This paper describes the development and evaluation of a prototype magnetic navigation system consisting of a wireless magnetometer placed at the users' hip streaming magnetic readings to a smartphone processing location algorithms. Human trials were conducted to assess the efficacy of the system by studying route-following performance with blind and sighted subjects using the navigation system for real-time guidance.

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.

Cassini tour navigation strategy

NASA Technical Reports Server (NTRS)

Roth, Duane; Alwar, Vijay; Bordi, John; Goodson, Troy; Hahn, Yungsun; Ionasescu, Rodica; Jones, Jeremy; Owen, William; Pojman, Joan; Roundhill, Ian;

33 CFR 245.20 - Determination of hazard to navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... navigation. 245.20 Section 245.20 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... weather conditions. (9) Length of time the obstruction has been in existence. (10) History of vessel...

33 CFR 245.20 - Determination of hazard to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation. 245.20 Section 245.20 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... weather conditions. (9) Length of time the obstruction has been in existence. (10) History of vessel...

33 CFR 245.20 - Determination of hazard to navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... navigation. 245.20 Section 245.20 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... weather conditions. (9) Length of time the obstruction has been in existence. (10) History of vessel...

33 CFR 245.20 - Determination of hazard to navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... navigation. 245.20 Section 245.20 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... weather conditions. (9) Length of time the obstruction has been in existence. (10) History of vessel...

33 CFR 245.20 - Determination of hazard to navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... navigation. 245.20 Section 245.20 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... weather conditions. (9) Length of time the obstruction has been in existence. (10) History of vessel...

Enhancing Navigation Skills through Audio Gaming.

PubMed

Sánchez, Jaime; Sáenz, Mauricio; Pascual-Leone, Alvaro; Merabet, Lotfi

2010-01-01

We present the design, development and initial cognitive evaluation of an Audio-based Environment Simulator (AbES). This software allows a blind user to navigate through a virtual representation of a real space for the purposes of training orientation and mobility skills. Our findings indicate that users feel satisfied and self-confident when interacting with the audio-based interface, and the embedded sounds allow them to correctly orient themselves and navigate within the virtual world. Furthermore, users are able to transfer spatial information acquired through virtual interactions into real world navigation and problem solving tasks.

14 CFR 23.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2012 CFR

2012-01-01

... navigation instruments. (c) A magnetic direction indicator. ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flight and navigation instruments. 23.1303... General § 23.1303 Flight and navigation instruments. Link to an amendment published at 76 FR 75760...

Interferometric inversion for passive imaging and navigation

DTIC Science & Technology

2017-05-01

AFRL-AFOSR-VA-TR-2017-0096 Interferometric inversion for passive imaging and navigation Laurent Demanet MASSACHUSETTS INSTITUTE OF TECHNOLOGY Final...COVERED (From - To) Feb 2015-Jan 2017 4. TITLE AND SUBTITLE Interferometric inversion for passive imaging and navigation 5a. CONTRACT NUMBER...Grant title: Interferometric inversion for passive imaging and navigation • Grant number: FA9550-15-1-0078 • Period: Feburary 2015 - January 2017

33 CFR 165.100 - Regulated Navigation Area: Navigable waters within the First Coast Guard District.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 3.05-1(b). (b) Definitions. Terms used in this section have the same meaning as those found in 33... District. (a) Regulated navigation area. All navigable waters of the United States, as that term is used in... tug of sufficient capability to promptly push or tow the tank barge away from danger of grounding or...

33 CFR 165.100 - Regulated Navigation Area: Navigable waters within the First Coast Guard District.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 3.05-1(b). (b) Definitions. Terms used in this section have the same meaning as those found in 33... District. (a) Regulated navigation area. All navigable waters of the United States, as that term is used in... tug of sufficient capability to promptly push or tow the tank barge away from danger of grounding or...

The Modality Effect on Reading Literacy: Perspectives from Students' Online Reading Habits, Cognitive and Metacognitive Strategies, and Web Navigation Skills across Regions

ERIC Educational Resources Information Center

Wu, Jiun Yu; Peng, Ya-Chun

2017-01-01

This study tested the effects of the modality of reading formats (electronic vs. print), online reading habits (engagement in different online reading activities), use of cognitive strategies, metacognitive knowledge, and navigation skills on printed and electronic reading literacy across regions. Participants were 31,784 fifteen-year-old students…

Parahippocampal and retrosplenial contributions to human spatial navigation

PubMed Central

Epstein, Russell A.

2010-01-01

Spatial navigation is a core cognitive ability in humans and animals. Neuroimaging studies have identified two functionally-defined brain regions that activate during navigational tasks and also during passive viewing of navigationally-relevant stimuli such as environmental scenes: the parahippocampal place area (PPA) and the retrosplenial complex (RSC). Recent findings indicate that the PPA and RSC play distinct and complementary roles in spatial navigation, with the PPA more concerned with representation of the local visual scene and RSC more concerned with situating the scene within the broader spatial environment. These findings are a first step towards understanding the separate components of the cortical network that mediates spatial navigation in humans. PMID:18760955

Cloud Absorption Radiometer Autonomous Navigation System - CANS

NASA Technical Reports Server (NTRS)

Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

2013-01-01

CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

14 CFR 29.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight and navigation instruments. 29.1303... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment General § 29.1303 Flight and navigation instruments. The following are required flight and navigational instruments: (a) An airspeed...

14 CFR 29.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight and navigation instruments. 29.1303... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment General § 29.1303 Flight and navigation instruments. The following are required flight and navigational instruments: (a) An airspeed...

14 CFR 27.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight and navigation instruments. 27.1303... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment General § 27.1303 Flight and navigation instruments. The following are the required flight and navigation instruments: (a) An airspeed...

14 CFR 27.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight and navigation instruments. 27.1303... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment General § 27.1303 Flight and navigation instruments. The following are the required flight and navigation instruments: (a) An airspeed...

14 CFR 25.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2012 CFR

2012-01-01

... indicator (nonstabilized magnetic compass). (b) The following flight and navigation instruments must be... (gyroscopically stabilized, magnetic or nonmagnetic). (c) The following flight and navigation instruments are... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flight and navigation instruments. 25.1303...

14 CFR 25.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2013 CFR

2013-01-01

... indicator (nonstabilized magnetic compass). (b) The following flight and navigation instruments must be... (gyroscopically stabilized, magnetic or nonmagnetic). (c) The following flight and navigation instruments are... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flight and navigation instruments. 25.1303...

14 CFR 27.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flight and navigation instruments. 27.1303... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment General § 27.1303 Flight and navigation instruments. The following are the required flight and navigation instruments: (a) An airspeed...

14 CFR 29.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flight and navigation instruments. 29.1303... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment General § 29.1303 Flight and navigation instruments. The following are required flight and navigational instruments: (a) An airspeed...

Space-based Scintillation Nowcasting with the Communications/Navigation Outage Forecast System

NASA Astrophysics Data System (ADS)

Groves, K.; Starks, M.; Beach, T.; Basu, S.

2008-12-01

The Air Force Research Laboratory's Communication/Navigation Outage Forecast System (C/NOFS) fuses ground- and space-based data in a near real-time physics-based model aimed at forecasting and nowcasting equatorial scintillations and their impacts on satellite communications and navigation. A key component of the system is the C/NOFS satellite that was launched into a low-inclination (13°) elliptical orbit (400 km x 850 km) in April 2008. The satellite contains six sensors to measure space environment parameters including electron density and temperature, ion density and drift, electric and magnetic fields and neutral wind, as well as a tri-band radio beacon transmitting at 150 MHz, 400 MHz and 1067 MHz. Scintillation nowcasts are derived from measuring the one-dimensional in situ electron density fluctuations and subsequently modeling the propagation environment for satellite-to-ground radio links. The modeling process requires a number of simplifying assumptions regarding the three-dimensional structure of the ionosphere and the results are readily validated by comparisons with ground-based measurements of the satellite's tri-band beacon signals. In mid-September 2008 a campaign to perform detailed analyses of space-based scintillation nowcasts with numerous ground observations was conducted in the vicinity of Kwajalein Atoll, Marshall Islands. To maximize the collection of ground-truth data, the ALTAIR radar was employed to obtain detailed information on the spatial structure of the ionosphere during the campaign and to aid the improvement of space-based nowcasting algorithms. A comparison of these results will be presented; it appears that detailed information on the electron density structure is a limiting factor in modeling the scintillation environment from in situ observations.

Behavioral Mapless Navigation Using Rings

NASA Technical Reports Server (NTRS)

Monroe, Randall P.; Miller, Samuel A.; Bradley, Arthur T.

2012-01-01

This paper presents work on the development and implementation of a novel approach to robotic navigation. In this system, map-building and localization for obstacle avoidance are discarded in favor of moment-by-moment behavioral processing of the sonar sensor data. To accomplish this, we developed a network of behaviors that communicate through the passing of rings, data structures that are similar in form to the sonar data itself and express the decisions of each behavior. Through the use of these rings, behaviors can moderate each other, conflicting impulses can be mediated, and designers can easily connect modules to create complex emergent navigational techniques. We discuss the development of a number of these modules and their successful use as a navigation system in the Trinity omnidirectional robot.

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

Compensation of Horizontal Gravity Disturbances for High Precision Inertial Navigation

PubMed Central

Cao, Juliang; Wu, Meiping; Lian, Junxiang; Cai, Shaokun; Wang, Lin

2018-01-01

Horizontal gravity disturbances are an important factor that affects the accuracy of inertial navigation systems in long-duration ship navigation. In this paper, from the perspective of the coordinate system and vector calculation, the effects of horizontal gravity disturbance on the initial alignment and navigation calculation are simultaneously analyzed. Horizontal gravity disturbances cause the navigation coordinate frame built in initial alignment to not be consistent with the navigation coordinate frame in which the navigation calculation is implemented. The mismatching of coordinate frame violates the vector calculation law, which will have an adverse effect on the precision of the inertial navigation system. To address this issue, two compensation methods suitable for two different navigation coordinate frames are proposed, one of the methods implements the compensation in velocity calculation, and the other does the compensation in attitude calculation. Finally, simulations and ship navigation experiments confirm the effectiveness of the proposed methods. PMID:29562653

Does Navigation Always Predict Performance? Effects of Navigation on Digital Reading Are Moderated by Comprehension Skills

ERIC Educational Resources Information Center

Naumann, Johannes; Salmerón, Ladislao

2016-01-01

This study investigated interactive effects of navigation and offline comprehension skill on digital reading performance. As indicators of navigation, relevant page selection and irrelevant page selection were considered. In 533 Spanish high school students aged 11-17 positive effects of offline comprehension skill and relevant page selection on…

How the structure of Wikipedia articles influences user navigation.

PubMed

Lamprecht, Daniel; Lerman, Kristina; Helic, Denis; Strohmaier, Markus

2017-01-02

In this work we study how people navigate the information network of Wikipedia and investigate (i) free-form navigation by studying all clicks within the English Wikipedia over an entire month and (ii) goal-directed Wikipedia navigation by analyzing wikigames, where users are challenged to retrieve articles by following links. To study how the organization of Wikipedia articles in terms of layout and links affects navigation behavior, we first investigate the characteristics of the structural organization and of hyperlinks in Wikipedia and then evaluate link selection models based on article structure and other potential influences in navigation, such as the generality of an article's topic. In free-form Wikipedia navigation, covering all Wikipedia usage scenarios, we find that click choices can be best modeled by a bias towards article structure, such as a tendency to click links located in the lead section. For the goal-directed navigation of wikigames, our findings confirm the zoom-out and the homing-in phases identified by previous work, where users are guided by generality at first and textual similarity to the target later. However, our interpretation of the link selection models accentuates that article structure is the best explanation for the navigation paths in all except these initial and final stages. Overall, we find evidence that users more frequently click on links that are located close to the top of an article. The structure of Wikipedia articles, which places links to more general concepts near the top, supports navigation by allowing users to quickly find the better-connected articles that facilitate navigation. Our results highlight the importance of article structure and link position in Wikipedia navigation and suggest that better organization of information can help make information networks more navigable.

How the structure of Wikipedia articles influences user navigation

NASA Astrophysics Data System (ADS)

Lamprecht, Daniel; Lerman, Kristina; Helic, Denis; Strohmaier, Markus

2017-01-01

In this work we study how people navigate the information network of Wikipedia and investigate (i) free-form navigation by studying all clicks within the English Wikipedia over an entire month and (ii) goal-directed Wikipedia navigation by analyzing wikigames, where users are challenged to retrieve articles by following links. To study how the organization of Wikipedia articles in terms of layout and links affects navigation behavior, we first investigate the characteristics of the structural organization and of hyperlinks in Wikipedia and then evaluate link selection models based on article structure and other potential influences in navigation, such as the generality of an article's topic. In free-form Wikipedia navigation, covering all Wikipedia usage scenarios, we find that click choices can be best modeled by a bias towards article structure, such as a tendency to click links located in the lead section. For the goal-directed navigation of wikigames, our findings confirm the zoom-out and the homing-in phases identified by previous work, where users are guided by generality at first and textual similarity to the target later. However, our interpretation of the link selection models accentuates that article structure is the best explanation for the navigation paths in all except these initial and final stages. Overall, we find evidence that users more frequently click on links that are located close to the top of an article. The structure of Wikipedia articles, which places links to more general concepts near the top, supports navigation by allowing users to quickly find the better-connected articles that facilitate navigation. Our results highlight the importance of article structure and link position in Wikipedia navigation and suggest that better organization of information can help make information networks more navigable.

How the structure of Wikipedia articles influences user navigation

PubMed Central

Lamprecht, Daniel; Lerman, Kristina; Helic, Denis; Strohmaier, Markus

2017-01-01

In this work we study how people navigate the information network of Wikipedia and investigate (i) free-form navigation by studying all clicks within the English Wikipedia over an entire month and (ii) goal-directed Wikipedia navigation by analyzing wikigames, where users are challenged to retrieve articles by following links. To study how the organization of Wikipedia articles in terms of layout and links affects navigation behavior, we first investigate the characteristics of the structural organization and of hyperlinks in Wikipedia and then evaluate link selection models based on article structure and other potential influences in navigation, such as the generality of an article's topic. In free-form Wikipedia navigation, covering all Wikipedia usage scenarios, we find that click choices can be best modeled by a bias towards article structure, such as a tendency to click links located in the lead section. For the goal-directed navigation of wikigames, our findings confirm the zoom-out and the homing-in phases identified by previous work, where users are guided by generality at first and textual similarity to the target later. However, our interpretation of the link selection models accentuates that article structure is the best explanation for the navigation paths in all except these initial and final stages. Overall, we find evidence that users more frequently click on links that are located close to the top of an article. The structure of Wikipedia articles, which places links to more general concepts near the top, supports navigation by allowing users to quickly find the better-connected articles that facilitate navigation. Our results highlight the importance of article structure and link position in Wikipedia navigation and suggest that better organization of information can help make information networks more navigable. PMID:28670171

Navigation Concepts for the James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Long, Anne; Leung, Dominic; Kelbel, David; Beckman, Mark; Grambling, Cheryl

2003-01-01

This paper evaluates the performance that can be achieved using candidate ground and onboard navigation approaches for operation of the James Webb Space Telescope, which will be in an orbit about the Sun-Earth L2 libration point. The ground navigation approach processes standard range and Doppler measurements from the Deep Space Network The onboard navigation approach processes celestial object measurements and/or ground-to- spacecraft Doppler measurements to autonomously estimate the spacecraft s position and velocity and Doppler reference frequency. Particular attention is given to assessing the absolute position and velocity accuracy that can be achieved in the presence of the frequent spacecraft reorientations and momentum unloads planned for this mission. The ground navigation approach provides stable navigation solutions using a tracking schedule of one 30-minute contact per day. The onboard navigation approach that uses only optical quality celestial object measurements provides stable autonomous navigation solutions. This study indicates that unmodeled changes in the solar radiation pressure cross-sectional area and modeled momentum unload velocity changes are the major error sources. These errors can be mitigated by modeling these changes, by estimating corrections to compensate for the changes, or by including acceleration measurements.

Electronic depiction of Instrument Approach Procedure (IAP) charts phase 1: development and evaluation

DOT National Transportation Integrated Search

1995-05-01

This report describes the research program being conducted at the Volpe National Transportation Systems Center on the development of electronic aeronautical charts. The design of electronic aeronautical navigation charts raises many interrelated huma...

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.

Disputing Viking navigation by polarized skylight.

PubMed

Roslund, C; Beckman, C

1994-07-20

The widely held notion that the Vikings utilized polarization of skylight on overcast days for navigational purposes is demonstrated to have no scientific basis. The use of polarized skylight for navigation under partly cloudfree skies should be treated with caution and skepticism.

14 CFR 25.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight and navigation instruments. 25.1303... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment General § 25.1303 Flight and navigation instruments. (a) The following flight and navigation instruments must be installed so that the...

14 CFR 25.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight and navigation instruments. 25.1303... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment General § 25.1303 Flight and navigation instruments. (a) The following flight and navigation instruments must be installed so that the...

14 CFR 29.1303 - Flight and navigation instruments.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flight and navigation instruments. 29.1303... navigation instruments. The following are required flight and navigational instruments: (a) An airspeed... sensitive altimeter. (c) A magnetic direction indicator. (d) A clock displaying hours, minutes, and seconds...

Navigation: National Plans; NAVSTAR-GPS; Laser Gyros

DTIC Science & Technology

1982-08-31

REFERENC-~CP STER . TECHNICAL REPORT ! "NO. 12686,-’-. - NAVIGATION: NATIONAL PLANS ; NAVSTAR-GPS; LASER GYROS CONTRACT NO. DAAK30-80-C-0073 31 AUGUST...Technical ReportAW Ng. riiNational Plans ; Navstar-GPS; S... : NavstarGPS; a3 Sept 1980 - 31 Aug 1982 ....Lasr Gyros. 6. PERFORMING ORG. REPORT NUMBER PRA...identify by block number) Navigation Navigation Satellites Laser Gyros Position-Location . NAVSTAR-GPS Fiberoptic Gyros Planning Global Positioning System

Clinical applications of virtual navigation bronchial intervention.

PubMed

Kajiwara, Naohiro; Maehara, Sachio; Maeda, Junichi; Hagiwara, Masaru; Okano, Tetsuya; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko

2018-01-01

In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors. We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases. Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely. Preoperative simulation using virtual navigation bronchial intervention reduces the surgeon's stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments

Interplanetary approach optical navigation with applications

NASA Technical Reports Server (NTRS)

Jerath, N.

1978-01-01

The use of optical data from onboard television cameras for the navigation of interplanetary spacecraft during the planet approach phase is investigated. Three optical data types were studied: the planet limb with auxiliary celestial references, the satellite-star, and the planet-star two-camera methods. Analysis and modelling issues related to the nature and information content of the optical methods were examined. Dynamic and measurement system modelling, data sequence design, measurement extraction, model estimation and orbit determination, as relating optical navigation, are discussed, and the various error sources were analyzed. The methodology developed was applied to the Mariner 9 and the Viking Mars missions. Navigation accuracies were evaluated at the control and knowledge points, with particular emphasis devoted to the combined use of radio and optical data. A parametric probability analysis technique was developed to evaluate navigation performance as a function of system reliabilities.

Navigating Space by the Stars - 16x9

NASA Image and Video Library

2018-06-18

A tool that has helped guide sailors across oceans for centuries is now being tested aboard the International Space Station as a potential emergency navigation tool for guiding future spacecraft across the cosmos. The Sextant Navigation investigation tests use of a hand-held sextant aboard the space station. Sextants have a telescope-like optical sight to take precise angle measurements between pairs of stars from land or sea, enabling navigation without computer assistance. NASA’s Gemini missions conducted the first sextant sightings from a spacecraft, and designers built a sextant into Apollo vehicles as a navigation backup in the event the crew lost communications from their spacecraft. Jim Lovell demonstrated on Apollo 8 that sextant navigation could return a space vehicle home. Astronauts conducted additional sextant experiments on Skylab. Read more about the Sextant experiment happening aboard the space station: https://www.nasa.gov/mission_pages/station/research/news/Sextant_ISS HD Download: https://archive.org/details/jsc2018m000418_Navigating_Space_by_the_Stars

Discussion on integrated digital chart data model and display platform for pocket navigator system (PNS)

NASA Astrophysics Data System (ADS)

Sui, Haigang; Xiao, Jinghuan; Wang, Qi; Li, Qian

2007-06-01

PDA (Personal Digital Assistant) is a useful tool for navigation which has many advantages such as its smallness and portability. In the meantime, digital charts have been found a wide application in past ten years, and many users are hoping for giving up the paper chart entirely and using ENC by the law. However, traditional paper chart is a nonreplaced tool for people in hydrographical survey and other application fields, and would coexist with ENC for a long time. How to manage and display integrated chart for traditional paper chart and ENC together in PDA for navigating is still an unsolved problem. Aiming at this, a new integrated spatial data model and display techniques for ENC and paper chart are presented. The core idea of the new algorithm is to build an integrated spatial data model, structure and display environment for both paper chart and ENC. Based on the above algorithms and strategies, an Integrated Electronic Chart Pocket Navigator System named PNS based on PDA was developed. It has been applied in Tianjin Marine Safety Administration Bureau and obtained a good evaluation.

33 CFR 162.30 - Channel of Tuckerton Creek, N.J.; navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Channel of Tuckerton Creek, N.J.; navigation. 162.30 Section 162.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Tuckerton Creek, N.J.; navigation. (a) Power boats or other vessels propelled by machinery shall not proceed...

Mars rover local navigation and hazard avoidance

NASA Technical Reports Server (NTRS)

Wilcox, B. H.; Gennery, D. B.; Mishkin, A. H.

1989-01-01

A Mars rover sample return mission has been proposed for the late 1990's. Due to the long speed-of-light delays between earth and Mars, some autonomy on the rover is highly desirable. JPL has been conducting research in two possible modes of rover operation, Computer-Aided Remote Driving and Semiautonomous Navigation. A recently-completed research program used a half-scale testbed vehicle to explore several of the concepts in semiautonomous navigation. A new, full-scale vehicle with all computational and power resources on-board will be used in the coming year to demonstrate relatively fast semiautonomous navigation. The computational and power requirements for Mars rover local navigation and hazard avoidance are discussed.

Mars Rover Local Navigation And Hazard Avoidance

NASA Astrophysics Data System (ADS)

Wilcox, B. H.; Gennery, D. B.; Mishkin, A. H.

1989-03-01

A Mars rover sample return mission has been proposed for the late 1990's. Due to the long speed-of-light delays between Earth and Mars, some autonomy on the rover is highly desirable. JPL has been conducting research in two possible modes of rover operation, Computer-Aided Remote Driving and Semiautonomous Navigation. A recently-completed research program used a half-scale testbed vehicle to explore several of the concepts in semiautonomous navigation. A new, full-scale vehicle with all computational and power resources on-board will be used in the coming year to demonstrate relatively fast semiautonomous navigation. The computational and power requirements for Mars rover local navigation and hazard avoidance are discussed.

Conceptual Design of a Communication-Based Deep Space Navigation Network

NASA Technical Reports Server (NTRS)

Anzalone, Evan J.; Chuang, C. H.

2012-01-01

As the need grows for increased autonomy and position knowledge accuracy to support missions beyond Earth orbit, engineers must push and develop more advanced navigation sensors and systems that operate independent of Earth-based analysis and processing. Several spacecraft are approaching this problem using inter-spacecraft radiometric tracking and onboard autonomous optical navigation methods. This paper proposes an alternative implementation to aid in spacecraft position fixing. The proposed method Network-Based Navigation technique takes advantage of the communication data being sent between spacecraft and between spacecraft and ground control to embed navigation information. The navigation system uses these packets to provide navigation estimates to an onboard navigation filter to augment traditional ground-based radiometric tracking techniques. As opposed to using digital signal measurements to capture inherent information of the transmitted signal itself, this method relies on the embedded navigation packet headers to calculate a navigation estimate. This method is heavily dependent on clock accuracy and the initial results show the promising performance of a notional system.

Experimental determination of the navigation error of the 4-D navigation, guidance, and control systems on the NASA B-737 airplane

NASA Technical Reports Server (NTRS)

Knox, C. E.

1978-01-01

Navigation error data from these flights are presented in a format utilizing three independent axes - horizontal, vertical, and time. The navigation position estimate error term and the autopilot flight technical error term are combined to form the total navigation error in each axis. This method of error presentation allows comparisons to be made between other 2-, 3-, or 4-D navigation systems and allows experimental or theoretical determination of the navigation error terms. Position estimate error data are presented with the navigation system position estimate based on dual DME radio updates that are smoothed with inertial velocities, dual DME radio updates that are smoothed with true airspeed and magnetic heading, and inertial velocity updates only. The normal mode of navigation with dual DME updates that are smoothed with inertial velocities resulted in a mean error of 390 m with a standard deviation of 150 m in the horizontal axis; a mean error of 1.5 m low with a standard deviation of less than 11 m in the vertical axis; and a mean error as low as 252 m with a standard deviation of 123 m in the time axis.

How does electromagnetic navigation stack up against infrared navigation in minimally invasive total knee arthroplasties?

PubMed

Lionberger, David R; Weise, Jennifer; Ho, David M; Haddad, John L

2008-06-01

Forty-six primary total knee arthroplasties were performed using either an electromagnetic (EM) or infrared (IR) navigation system. In this IRB-approved study, patients were evaluated clinically and for accuracy using spiral computed tomographic imaging and 36-in standing radiographs. Although EM navigation was subject to metal interference, it was not as drastic as line-of-sight interference with IR navigation. Mechanical alignment was ideal in 92.9% of EM and 90.0% of IR cases based on spiral computed tomographic imaging and 100% of EM and 95% of IR cases based on x-ray. Individual measurements of component varus/valgus and sagittal measurements showed EM to be equivalent to IR, with both systems producing subdegree accuracy in 95% of the readings.

14 CFR 121.305 - Flight and navigational equipment.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Flight and navigational equipment. 121.305... Flight and navigational equipment. No person may operate an airplane unless it is equipped with the following flight and navigational instruments and equipment: (a) An airspeed indicating system with heated...

14 CFR 121.305 - Flight and navigational equipment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Flight and navigational equipment. 121.305... Flight and navigational equipment. No person may operate an airplane unless it is equipped with the following flight and navigational instruments and equipment: (a) An airspeed indicating system with heated...

14 CFR 121.305 - Flight and navigational equipment.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Flight and navigational equipment. 121.305... Flight and navigational equipment. No person may operate an airplane unless it is equipped with the following flight and navigational instruments and equipment: (a) An airspeed indicating system with heated...

14 CFR 121.305 - Flight and navigational equipment.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Flight and navigational equipment. 121.305... Flight and navigational equipment. No person may operate an airplane unless it is equipped with the following flight and navigational instruments and equipment: (a) An airspeed indicating system with heated...

Characterizing Navigation in Interactive Learning Environments

ERIC Educational Resources Information Center

Liang, Hai-Ning; Sedig, Kamran

2009-01-01

Interactive learning environments (ILEs) are increasingly used to support and enhance instruction and learning experiences. ILEs maintain and display information, allowing learners to interact with this information. One important method of interacting with information is navigation. Often, learners are required to navigate through the information…

Effects of Patient Navigation on Patient Satisfaction Outcomes.

PubMed

Post, Douglas M; McAlearney, Ann Scheck; Young, Gregory S; Krok-Schoen, Jessica L; Plascak, Jesse J; Paskett, Electra D

2015-12-01

Patient navigation (PN) may reduce cancer health disparities. Few studies have investigated the effects of PN on patient-reported satisfaction with care or assessed patients' satisfaction with navigators. The objectives of this study are to test the effects of PN on patient satisfaction with cancer care, assess patients' satisfaction with navigators, and examine the impact of barriers to care on satisfaction for persons with abnormal cancer-related screening tests or symptoms. Study participants included women and men with abnormal breast, cervical, or colorectal cancer screening tests and/or symptoms receiving care at 18 clinics. Navigated (n=416) and non-navigated (n=292) patients completed baseline and end-of-study measures. There was no significant difference between navigated and non-navigated patients in change in patient satisfaction with cancer care from baseline to exit. African-American (p<0.001), single (p=0.03), low income (p<0.01), and uninsured patients (p<0.001) were significantly less likely to report high patient satisfaction at baseline. A significant effect was found for change in satisfaction over time by employment status (p=0.04), with full-time employment showing the most improvement. The interaction between satisfaction with navigators and satisfaction with care over time was marginally significant (p=0.08). Baseline satisfaction was lower for patients who reported a barrier to care (p=0.02). Patients reporting other-focused barriers (p=0.03), including transportation (p=0.02), had significantly lower increases in satisfaction over time. Overall, results suggested that assessing barriers to cancer care and tailoring navigation to barrier type could enhance patients' experiences with health care. PN may have positive effects for healthcare organizations struggling to enhance quality of care.

An Effective Terrain Aided Navigation for Low-Cost Autonomous Underwater Vehicles.

PubMed

Zhou, Ling; Cheng, Xianghong; Zhu, Yixian; Dai, Chenxi; Fu, Jinbo

2017-03-25

Terrain-aided navigation is a potentially powerful solution for obtaining submerged position fixes for autonomous underwater vehicles. The application of terrain-aided navigation with high-accuracy inertial navigation systems has demonstrated meter-level navigation accuracy in sea trials. However, available sensors may be limited depending on the type of the mission. Such limitations, especially for low-grade navigation sensors, not only degrade the accuracy of traditional navigation systems, but further impact the ability to successfully employ terrain-aided navigation. To address this problem, a tightly-coupled navigation is presented to successfully estimate the critical sensor errors by incorporating raw sensor data directly into an augmented navigation system. Furthermore, three-dimensional distance errors are calculated, providing measurement updates through the particle filter for absolute and bounded position error. The development of the terrain aided navigation system is elaborated for a vehicle equipped with a non-inertial-grade strapdown inertial navigation system, a 4-beam Doppler Velocity Log range sensor and a sonar altimeter. Using experimental data for navigation performance evaluation in areas with different terrain characteristics, the experiment results further show that the proposed method can be successfully applied to the low-cost AUVs and significantly improves navigation performance.

Fuzzy Behavior-Based Navigation for Planetary

NASA Technical Reports Server (NTRS)

Tunstel, Edward; Danny, Harrison; Lippincott, Tanya; Jamshidi, Mo

1997-01-01

Adaptive behavioral capabilities are necessary for robust rover navigation in unstructured and partially-mapped environments. A control approach is described which exploits the approximate reasoning capability of fuzzy logic to produce adaptive motion behavior. In particular, a behavior-based architecture for hierarchical fuzzy control of microrovers is presented. Its structure is described, as well as mechanisms of control decision-making which give rise to adaptive behavior. Control decisions for local navigation result from a consensus of recommendations offered only by behaviors that are applicable to current situations. Simulation predicts the navigation performance on a microrover in simplified Mars-analog terrain.

Enhancing Navigation Skills through Audio Gaming

PubMed Central

Sánchez, Jaime; Sáenz, Mauricio; Pascual-Leone, Alvaro; Merabet, Lotfi

2014-01-01

We present the design, development and initial cognitive evaluation of an Audio-based Environment Simulator (AbES). This software allows a blind user to navigate through a virtual representation of a real space for the purposes of training orientation and mobility skills. Our findings indicate that users feel satisfied and self-confident when interacting with the audio-based interface, and the embedded sounds allow them to correctly orient themselves and navigate within the virtual world. Furthermore, users are able to transfer spatial information acquired through virtual interactions into real world navigation and problem solving tasks. PMID:25505796

Celestial Navigation

ERIC Educational Resources Information Center

Rosenkrantz, Kurt

2005-01-01

In the unit described in this article, students discover the main principles of navigation, build tools to observe celestial bodies, and apply their new skills to finding their position on Earth. Along the way students see how science, mathematics, technology, and history are intertwined.

NAVO MSRC Navigator. Spring 2008

DTIC Science & Technology

2008-01-01

EINSTEIN and DAVINCI Come to the MSRC The Porthole 19 Visitors to the Naval Oceanographic Office Major Shared Resource Center Navigator Tools and...traditionally considered one of the leading track guidance tools for forecasters. As an example, we consider the case of Hurricane Figure 2. The...MSRC NAVIGATOR EINSTEIN and DAVINCI Come to the MSRC Christine Cuicchi, Computational Science and Applications Lead, NAVO MSRC The Technology

[Magnetic navigation for ablation of cardiac arrhythmias].

PubMed

Chen, Jian; Hoff, Per Ivar; Solheim, Eivind; Schuster, Peter; Off, Morten Kristian; Ohm, Ole-Jørgen

2010-08-12

The first use of magnetic navigation for radiofrequency ablation of supraventricular tachycardias, was published in 2004. Subsequently, the method has been used for treatment of most types of tachyarrhythmias. This paper provides an overview of the method, with special emphasis on usefulness of a new remote-controlled magnetic navigation system. The paper is based on our own scientific experience and literature identified through a non-systematic search in PubMed. The magnetic navigation system consists of two external electromagnets (to be placed on opposite sides of the patient), which guide an ablation catheter (with a small magnet at the tip of the catheter) to the target area in the heart. The accuracy of this procedure is higher than that with manual navigation. Personnel can be quickly trained to use remote magnetic navigation, but the procedure itself is time-consuming, particularly for patients with atrial fibrillation. The major advantage is a considerably lower radiation burden to both patient and operator, in some studies more than 50 %, and a corresponding reduction in physical strain on the operator. The incidence of procedure-related complications seems to be lower than that observed with use of manually operated ablation catheters. Work is ongoing to improve magnetic ablation catheters and methods that can simplify mapping procedures and improve efficacy of arrhythmia ablation. The basic cost for installing a complete magnetic navigation laboratory may be three times that of a conventional electrophysiological laboratory. The new magnetic navigation system has proved to be applicable during ablation for a variety of tachyarrhythmias, but is still under development.

Evaluation of Relative Navigation Algorithms for Formation-Flying Satellites

NASA Technical Reports Server (NTRS)

Kelbel, David; Lee, Taesul; Long, Anne; Carpenter, J. Russell; Gramling, Cheryl

2001-01-01

Goddard Space Flight Center is currently developing advanced spacecraft systems to provide autonomous navigation and control of formation flyers. This paper discusses autonomous relative navigation performance for formations in eccentric, medium, and high-altitude Earth orbits using Global Positioning System (GPS) Standard Positioning Service (SPS) and intersatellite range measurements. The performance of several candidate relative navigation approaches is evaluated. These analyses indicate that the relative navigation accuracy is primarily a function of the frequency of acquisition and tracking of the GPS signals. A relative navigation position accuracy of 0.5 meters root-mean-square (RMS) can be achieved for formations in medium-attitude eccentric orbits that can continuously track at least one GPS signal. A relative navigation position accuracy of better than 75 meters RMS can be achieved for formations in high-altitude eccentric orbits that have sparse tracking of the GPS signals. The addition of round-trip intersatellite range measurements can significantly improve relative navigation accuracy for formations with sparse tracking of the GPS signals.

Academic health sciences library Website navigation: an analysis of forty-one Websites and their navigation tools

PubMed Central

Brower, Stewart M.

2004-01-01

Background: The analysis included forty-one academic health sciences library (HSL) Websites as captured in the first two weeks of January 2001. Home pages and persistent navigational tools (PNTs) were analyzed for layout, technology, and links, and other general site metrics were taken. Methods: Websites were selected based on rank in the National Network of Libraries of Medicine, with regional and resource libraries given preference on the basis that these libraries are recognized as leaders in their regions and would be the most reasonable source of standards for best practice. A three-page evaluation tool was developed based on previous similar studies. All forty-one sites were evaluated in four specific areas: library general information, Website aids and tools, library services, and electronic resources. Metrics taken for electronic resources included orientation of bibliographic databases alphabetically by title or by subject area and with links to specifically named databases. Results: Based on the results, a formula for determining obligatory links was developed, listing items that should appear on all academic HSL Web home pages and PNTs. Conclusions: These obligatory links demonstrate a series of best practices that may be followed in the design and construction of academic HSL Websites. PMID:15494756

A risk analysis of winter navigation in Finnish sea areas.

PubMed

Valdez Banda, Osiris A; Goerlandt, Floris; Montewka, Jakub; Kujala, Pentti

2015-06-01

Winter navigation is a complex but common operation in north-European sea areas. In Finnish waters, the smooth flow of maritime traffic and safety of vessel navigation during the winter period are managed through the Finnish-Swedish winter navigation system (FSWNS). This article focuses on accident risks in winter navigation operations, beginning with a brief outline of the FSWNS. The study analyses a hazard identification model of winter navigation and reviews accident data extracted from four winter periods. These are adopted as a basis for visualizing the risks in winter navigation operations. The results reveal that experts consider ship independent navigation in ice conditions the most complex navigational operation, which is confirmed by accident data analysis showing that the operation constitutes the type of navigation with the highest number of accidents reported. The severity of the accidents during winter navigation is mainly categorized as less serious. Collision is the most typical accident in ice navigation and general cargo the type of vessel most frequently involved in these accidents. Consolidated ice, ice ridges and ice thickness between 15 and 40cm represent the most common ice conditions in which accidents occur. Thus, the analysis presented in this article establishes the key elements for identifying the operation types which would benefit most from further safety engineering and safety or risk management development. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Effective Terrain Aided Navigation for Low-Cost Autonomous Underwater Vehicles

PubMed Central

Zhou, Ling; Cheng, Xianghong; Zhu, Yixian; Dai, Chenxi; Fu, Jinbo

2017-01-01

Terrain-aided navigation is a potentially powerful solution for obtaining submerged position fixes for autonomous underwater vehicles. The application of terrain-aided navigation with high-accuracy inertial navigation systems has demonstrated meter-level navigation accuracy in sea trials. However, available sensors may be limited depending on the type of the mission. Such limitations, especially for low-grade navigation sensors, not only degrade the accuracy of traditional navigation systems, but further impact the ability to successfully employ terrain-aided navigation. To address this problem, a tightly-coupled navigation is presented to successfully estimate the critical sensor errors by incorporating raw sensor data directly into an augmented navigation system. Furthermore, three-dimensional distance errors are calculated, providing measurement updates through the particle filter for absolute and bounded position error. The development of the terrain aided navigation system is elaborated for a vehicle equipped with a non-inertial-grade strapdown inertial navigation system, a 4-beam Doppler Velocity Log range sensor and a sonar altimeter. Using experimental data for navigation performance evaluation in areas with different terrain characteristics, the experiment results further show that the proposed method can be successfully applied to the low-cost AUVs and significantly improves navigation performance. PMID:28346346

Memorable Messages for Navigating College Life

ERIC Educational Resources Information Center

Nazione, Samantha; Laplante, Carolyn; Smith, Sandi W.; Cornacchione, Jennifer; Russell, Jessica; Stohl, Cynthia

2011-01-01

This manuscript details an investigation of memorable messages that help students navigate college life using a control theory framework. Researchers conducted face-to-face interviews with 61 undergraduate students who recalled a specific memorable message that helped them as they navigated college. Results of this formative study show the…

46 CFR 169.691 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Navigation lights. 169.691 Section 169.691 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... lights. Navigation light systems must meet the requirements of § 111.75-17 of this chapter except the...

46 CFR 169.691 - Navigation lights.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Navigation lights. 169.691 Section 169.691 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... lights. Navigation light systems must meet the requirements of § 111.75-17 of this chapter except the...

46 CFR 169.691 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Navigation lights. 169.691 Section 169.691 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... lights. Navigation light systems must meet the requirements of § 111.75-17 of this chapter except the...

46 CFR 169.691 - Navigation lights.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Navigation lights. 169.691 Section 169.691 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... lights. Navigation light systems must meet the requirements of § 111.75-17 of this chapter except the...

46 CFR 169.691 - Navigation lights.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Navigation lights. 169.691 Section 169.691 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... lights. Navigation light systems must meet the requirements of § 111.75-17 of this chapter except the...

Inner Harbor Navigation Canal Basin Velocity Analysis

DTIC Science & Technology

2014-10-01

ER D C/ CH L TR -1 4- 12 Inner Harbor Navigation Canal Basin Velocity Analysis Co as ta l a nd H yd ra ul ic s La bo ra to ry...Mississippi River Gulf Outlet (MRGO). The structures allow for continued navigation, and the gate structures are designed to remain open during...Water Way (GIWW) just east of the Mississippi River Gulf Outlet (MRGO). The planned structures allow for continued navigation in the IHNC, Bayou

45 CFR 155.210 - Navigator program standards.

Code of Federal Regulations, 2014 CFR

2014-10-01

... individuals to be awarded Navigator grants, designed to prevent, minimize and mitigate any conflicts of... substantive benefits or comparative benefits of different health plans. (D) Requiring that a Navigator hold an...

Fuzzy Logic Based Control for Autonomous Mobile Robot Navigation

PubMed Central

Masmoudi, Mohamed Slim; Masmoudi, Mohamed

2016-01-01

This paper describes the design and the implementation of a trajectory tracking controller using fuzzy logic for mobile robot to navigate in indoor environments. Most of the previous works used two independent controllers for navigation and avoiding obstacles. The main contribution of the paper can be summarized in the fact that we use only one fuzzy controller for navigation and obstacle avoidance. The used mobile robot is equipped with DC motor, nine infrared range (IR) sensors to measure the distance to obstacles, and two optical encoders to provide the actual position and speeds. To evaluate the performances of the intelligent navigation algorithms, different trajectories are used and simulated using MATLAB software and SIMIAM navigation platform. Simulation results show the performances of the intelligent navigation algorithms in terms of simulation times and travelled path. PMID:27688748

Incidental memory and navigation in panoramic virtual reality for electronic commerce.

PubMed

Howes, A; Miles, G E; Payne, S J; Mitchell, C D; Davies, A J

2001-01-01

Recently much effort has been dedicated to designing and implementing World Wide Web sites for virtual shopping and e-commerce. Despite this effort, relatively little empirical work has been done to determine the effectiveness with which different site designs sell products. We report three experiments in which participants were asked to search for products in various experimental e-commerce sites. Across the experiments participants were asked to search in either QTVR (QuickTime Virtual Reality), hypertext, or pictorially rich hypertext environments; they were then tested for their ability to recall the products seen and to recognize product locations. The experiments demonstrated that when using QTVR (Experiments 1, 2, and 3) or pictorial environments (Experiment 2), participants retained more information about products that were incidental to their goals. In two of the experiments it was shown that participants navigated more efficiently when using a QTVR environment. The costs and benefits of using 3D virtual environments for on-line shops are discussed. Actual or potential applications of this research include support for the development of e-commerce design guidelines.

SU-F-P-42: “To Navigate, Or Not to Navigate: HDR BT in Recurrent Spine Lesions”

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voros, L; Cohen, G; Zaider, M

Purpose: We compare the accuracy of HDR catheter placement for paraspinal lesions using O-arm CBCT imaging combined with StealthStation navigation and traditional fluoroscopically guided catheter placement. Methods: CT and MRI scans were acquired pre-treatment to outline the lesions and design treatment plans (pre-plans) to meet dosimetric constrains. The pre-planned catheter trajectories were transferred into the StealthStation Navigation system prior to the surgery. The StealthStation is an infra red (IR) optical navigation system used for guidance of surgical instruments. An intraoperative CBCT scan (O-arm) was acquired with reference IR optical fiducials anchored onto the patient and registered with the preplan imagemore » study to guide surgical instruments in relation to the patients’ anatomy and to place the brachytherapy catheters along the pre-planned trajectories. The final treatment plan was generated based on a 2nd intraoperative CBCT scan reflecting achieved implant geometry. The 2nd CBCT was later registered with the initial CT scan to compare the preplanned dwell positions with actual dwell positions (catheter placements). Similar workflow was used in placement of 8 catheters (1 patient) without navigation, but under fluoroscopy guidance in an interventional radiology suite. Results: A total of 18 catheters (3 patients) were placed using navigation assisted surgery. Average displacement of 0.66 cm (STD=0.37cm) was observed between the pre-plan source positions and actual source positions in the 3 dimensional space. This translates into an average 0.38 cm positioning error in one direction including registration errors, digitization errors, and the surgeons ability to follow the planned trajectory. In comparison, average displacement of non-navigated catheters was 0.50 cm (STD=0.22cm). Conclusion: Spinal lesion HDR brachytherapy planning is a difficult task. Catheter placement has a direct impact on target coverage and dose to critical structures

Navigating 3D electron microscopy maps with EM-SURFER.

PubMed

Esquivel-Rodríguez, Juan; Xiong, Yi; Han, Xusi; Guang, Shuomeng; Christoffer, Charles; Kihara, Daisuke

2015-05-30

The Electron Microscopy DataBank (EMDB) is growing rapidly, accumulating biological structural data obtained mainly by electron microscopy and tomography, which are emerging techniques for determining large biomolecular complex and subcellular structures. Together with the Protein Data Bank (PDB), EMDB is becoming a fundamental resource of the tertiary structures of biological macromolecules. To take full advantage of this indispensable resource, the ability to search the database by structural similarity is essential. However, unlike high-resolution structures stored in PDB, methods for comparing low-resolution electron microscopy (EM) density maps in EMDB are not well established. We developed a computational method for efficiently searching low-resolution EM maps. The method uses a compact fingerprint representation of EM maps based on the 3D Zernike descriptor, which is derived from a mathematical series expansion for EM maps that are considered as 3D functions. The method is implemented in a web server named EM-SURFER, which allows users to search against the entire EMDB in real-time. EM-SURFER compares the global shapes of EM maps. Examples of search results from different types of query structures are discussed. We developed EM-SURFER, which retrieves structurally relevant matches for query EM maps from EMDB within seconds. The unique capability of EM-SURFER to detect 3D shape similarity of low-resolution EM maps should prove invaluable in structural biology.

Computer Assisted Navigation in Knee Arthroplasty

PubMed Central

Bae, Dae Kyung

2011-01-01

Computer assisted surgery (CAS) was used to improve the positioning of implants during total knee arthroplasty (TKA). Most studies have reported that computer assisted navigation reduced the outliers of alignment and component malpositioning. However, additional sophisticated studies are necessary to determine if the improvement of alignment will improve long-term clinical results and increase the survival rate of the implant. Knowledge of CAS-TKA technology and understanding the advantages and limitations of navigation are crucial to the successful application of the CAS technique in TKA. In this article, we review the components of navigation, classification of the system, surgical method, potential error, clinical results, advantages, and disadvantages. PMID:22162787

32 CFR 644.3 - Navigation projects.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 4 2011-07-01 2011-07-01 false Navigation projects. 644.3 Section 644.3 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Project Planning Civil Works § 644.3 Navigation projects. (a) Land to be acquired in fee...

Pragmatic Randomized, Controlled Trial of Patient Navigators and Enhanced Personal Health Records in CKD.

PubMed

Navaneethan, Sankar D; Jolly, Stacey E; Schold, Jesse D; Arrigain, Susana; Nakhoul, Georges; Konig, Victoria; Hyland, Jennifer; Burrucker, Yvette K; Dann, Priscilla Davis; Tucky, Barbara H; Sharp, John; Nally, Joseph V

2017-09-07

Patient navigators and enhanced personal health records improve the quality of health care delivered in other disease states. We aimed to develop a navigator program for patients with CKD and an electronic health record-based enhanced personal health record to disseminate CKD stage-specific goals of care and education. We also conducted a pragmatic randomized clinical trial to compare the effect of a navigator program for patients with CKD with enhanced personal health record and compare their combination compared with usual care among patients with CKD stage 3b/4. Two hundred and nine patients from six outpatient clinics (in both primary care and nephrology settings) were randomized in a 2×2 factorial design into four-study groups: ( 1 ) enhanced personal health record only, ( 2 ) patient navigator only, ( 3 ) both, and ( 4 ) usual care (control) group. Primary outcome measure was the change in eGFR over a 2-year follow-up period. Secondary outcome measures included acquisition of appropriate CKD-related laboratory measures, specialty referrals, and hospitalization rates. Median age of the study population was 68 years old, and 75% were white. At study entry, 54% of patients were followed by nephrologists, and 88% were on renin-angiotensin system blockers. After a 2-year follow-up, rate of decline in eGFR was similar across the four groups ( P =0.19). Measurements of CKD-related laboratory parameters were not significantly different among the groups. Furthermore, referral for dialysis education and vascular access placement, emergency room visits, and hospitalization rates were not statistically significant different between the groups. We successfully developed a patient navigator program and an enhanced personal health record for the CKD population. However, there were no differences in eGFR decline and other outcomes among the study groups. Larger and long-term studies along with cost-effectiveness analyses are needed to evaluate the role of patient navigators

Navigation domain representation for interactive multiview imaging.

PubMed

Maugey, Thomas; Daribo, Ismael; Cheung, Gene; Frossard, Pascal

2013-09-01

Enabling users to interactively navigate through different viewpoints of a static scene is a new interesting functionality in 3D streaming systems. While it opens exciting perspectives toward rich multimedia applications, it requires the design of novel representations and coding techniques to solve the new challenges imposed by the interactive navigation. In particular, the encoder must prepare a priori a compressed media stream that is flexible enough to enable the free selection of multiview navigation paths by different streaming media clients. Interactivity clearly brings new design constraints: the encoder is unaware of the exact decoding process, while the decoder has to reconstruct information from incomplete subsets of data since the server generally cannot transmit images for all possible viewpoints due to resource constrains. In this paper, we propose a novel multiview data representation that permits us to satisfy bandwidth and storage constraints in an interactive multiview streaming system. In particular, we partition the multiview navigation domain into segments, each of which is described by a reference image (color and depth data) and some auxiliary information. The auxiliary information enables the client to recreate any viewpoint in the navigation segment via view synthesis. The decoder is then able to navigate freely in the segment without further data request to the server; it requests additional data only when it moves to a different segment. We discuss the benefits of this novel representation in interactive navigation systems and further propose a method to optimize the partitioning of the navigation domain into independent segments, under bandwidth and storage constraints. Experimental results confirm the potential of the proposed representation; namely, our system leads to similar compression performance as classical inter-view coding, while it provides the high level of flexibility that is required for interactive streaming. Because of

Ego-motion based on EM for bionic navigation

NASA Astrophysics Data System (ADS)

Yue, Xiaofeng; Wang, L. J.; Liu, J. G.

2015-12-01

Researches have proved that flying insects such as bees can achieve efficient and robust flight control, and biologists have explored some biomimetic principles regarding how they control flight. Based on those basic studies and principles acquired from the flying insects, this paper proposes a different solution of recovering ego-motion for low level navigation. Firstly, a new type of entropy flow is provided to calculate the motion parameters. Secondly, EKF, which has been used for navigation for some years to correct accumulated error, and estimation-Maximization, which is always used to estimate parameters, are put together to determine the ego-motion estimation of aerial vehicles. Numerical simulation on MATLAB has proved that this navigation system provides more accurate position and smaller mean absolute error than pure optical flow navigation. This paper has done pioneering work in bionic mechanism to space navigation.

Hybrid DynaCT-guided electromagnetic navigational bronchoscopic biopsy†.

PubMed

Ng, Calvin S H; Yu, Simon C H; Lau, Rainbow W H; Yim, Anthony P C

2016-01-01

Electromagnetic navigational bronchoscopy-guided biopsy of small pulmonary nodules can be challenging. Navigational error of the system and movement of the biopsy tool during its deployment adversely affect biopsy success. Furthermore, conventional methods to confirm navigational success such as fluoroscopy and radial endobronchial ultrasound become less useful for the biopsy of small lesions. A hybrid operating theatre can provide unparalleled real-time imaging through DynaCT scan to guide and confirm successful navigation and biopsy of difficult-to-reach or small lesions. We describe our technique for DynaCT image-guided electromagnetic navigational bronchoscopic biopsy of a small pulmonary nodule in the hybrid operating theatre. The advantages, disadvantages and special considerations in adopting this approach are discussed. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Advanced Endoscopic Navigation: Surgical Big Data, Methodology, and Applications.

PubMed

Luo, Xiongbiao; Mori, Kensaku; Peters, Terry M

2018-06-04

Interventional endoscopy (e.g., bronchoscopy, colonoscopy, laparoscopy, cystoscopy) is a widely performed procedure that involves either diagnosis of suspicious lesions or guidance for minimally invasive surgery in a variety of organs within the body cavity. Endoscopy may also be used to guide the introduction of certain items (e.g., stents) into the body. Endoscopic navigation systems seek to integrate big data with multimodal information (e.g., computed tomography, magnetic resonance images, endoscopic video sequences, ultrasound images, external trackers) relative to the patient's anatomy, control the movement of medical endoscopes and surgical tools, and guide the surgeon's actions during endoscopic interventions. Nevertheless, it remains challenging to realize the next generation of context-aware navigated endoscopy. This review presents a broad survey of various aspects of endoscopic navigation, particularly with respect to the development of endoscopic navigation techniques. First, we investigate big data with multimodal information involved in endoscopic navigation. Next, we focus on numerous methodologies used for endoscopic navigation. We then review different endoscopic procedures in clinical applications. Finally, we discuss novel techniques and promising directions for the development of endoscopic navigation.

Cancer Patient Navigator Tasks across the Cancer Care Continuum

PubMed Central

Braun, Kathryn L.; Kagawa-Singer, Marjorie; Holden, Alan E. C.; Burhansstipanov, Linda; Tran, Jacqueline H.; Seals, Brenda F.; Corbie-Smith, Giselle; Tsark, JoAnn U.; Harjo, Lisa; Foo, Mary Anne; Ramirez, Amelie G.

2011-01-01

Cancer patient navigation (PN) programs have been shown to increase access to and utilization of cancer care for poor and underserved individuals. Despite mounting evidence of its value, cancer patient navigation is not universally understood or provided. We describe five PN programs and the range of tasks their navigators provide across the cancer care continuum (education and outreach, screening, diagnosis and staging, treatment, survivorship, and end-of-life). Tasks are organized by their potential to make cancer services understandable, available, accessible, affordable, appropriate, and accountable. Although navigators perform similar tasks across the five programs, their specific approaches reflect differences in community culture, context, program setting, and funding. Task lists can inform the development of programs, job descriptions, training, and evaluation. They also may be useful in the move to certify navigators and establish mechanisms for reimbursement for navigation services. PMID:22423178

Visual Navigation in Nocturnal Insects.

PubMed

Warrant, Eric; Dacke, Marie

2016-05-01

Despite their tiny eyes and brains, nocturnal insects have evolved a remarkable capacity to visually navigate at night. Whereas some use moonlight or the stars as celestial compass cues to maintain a straight-line course, others use visual landmarks to navigate to and from their nest. These impressive abilities rely on highly sensitive compound eyes and specialized visual processing strategies in the brain. ©2016 Int. Union Physiol. Sci./Am. Physiol. Soc.

Neuroendovascular magnetic navigation: clinical experience in ten patients.

PubMed

Dabus, Guilherme; Gerstle, Ronald J; Cross, Dewitte T; Derdeyn, Colin P; Moran, Christopher J

2007-04-01

The magnetic navigation system consists of an externally generated magnetic field that is used to control and steer a magnetically tipped microguidewire. The goal of this study was to demonstrate that the use of the magnetic navigation system and its magnetic microguidewire is feasible and safe in all types of neuroendovascular procedures. A magnetic navigation system is an interventional workstation that combines a biplanar fluoroscopy system with a computer-controlled magnetic field generator to provide both visualization and control of a magnetically activated endovascular microguidewire. Ten consecutive patients underwent a variety of neuroendovascular procedures using the magnetic guidance system and magnetic microguidewire. All patients presented with a neurovascular disease that was suitable for endovascular treatment. Multiple different devices and embolic agents were used. Of the ten patients, three were male and seven female. Their mean age was 53.9 years. The predominant neurovascular condition was the presence of intracranial aneurysm (nine patients). One patient had a left mandibular arteriovenous malformation. All treatments were successfully performed on the magnetic navigation system suite. The magnetic navigation system and the magnetic microguidewire allowed safe and accurate endovascular navigation allowing placement of the microcatheters in the desired location. There were no neurological complications or death in our series. The use of the magnetic navigation system and the magnetic microguidewire in the endovascular treatment of patients with neurovascular diseases is feasible and safe.

Training in patient navigation: A review of the research literature

PubMed Central

Ustjanauskas, Amy E.; Bredice, Marissa; Nuhaily, Sumayah; Kath, Lisa; Wells, Kristen J.

2016-01-01

Despite the proliferation of patient navigation programs designed to increase timely receipt of health care, little is known about the content and delivery of patient navigation training, or best practices in this arena. The current study begins to address these gaps in understanding, as it is the first study to comprehensively review descriptions of patient navigation training in the peer-reviewed research literature. Seventy-five patient navigation efficacy studies published since 1995, identified through PubMed and by the authors, were included in this narrative review. Fifty-nine of the included studies (79%) mentioned patient navigation training, and fifty-five of these studies additionally provided a description of training. Most studies did not thoroughly document patient navigation training practices. Additionally, several topics integral to the role of patient navigators, as well as components of training central to successful adult learning, were not commonly described in the research literature. Descriptions of training also varied widely across studies in terms of duration, location, format, learning strategies employed, occupation of trainer, and content. These findings demonstrate the need for established standards of navigator training as well as future research on the optimal delivery and content of patient navigation training. PMID:26656600

Visual navigation using edge curve matching for pinpoint planetary landing

NASA Astrophysics Data System (ADS)

Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei

2018-05-01

Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.

Fuzzy Behavior Modulation with Threshold Activation for Autonomous Vehicle Navigation

NASA Technical Reports Server (NTRS)

Tunstel, Edward

2000-01-01

This paper describes fuzzy logic techniques used in a hierarchical behavior-based architecture for robot navigation. An architectural feature for threshold activation of fuzzy-behaviors is emphasized, which is potentially useful for tuning navigation performance in real world applications. The target application is autonomous local navigation of a small planetary rover. Threshold activation of low-level navigation behaviors is the primary focus. A preliminary assessment of its impact on local navigation performance is provided based on computer simulations.

The impact of patient navigation on the delivery of diagnostic breast cancer care in the National Patient Navigation Research Program: a prospective meta-analysis

PubMed Central

Darnell, Julie S.; Ko, Naomi; Snyder, Fred; Paskett, Electra D.; Wells, Kristen J.; Whitley, Elizabeth M.; Griggs, Jennifer J.; Karnad, Anand; Young, Heather; Warren-Mears, Victoria; Simon, Melissa A.; Calhoun, Elizabeth

2016-01-01

Patient navigation is emerging as a standard in breast cancer care delivery, yet multi-site data on the impact of navigation at reducing delays along the continuum of care are lacking. The purpose of this study was to determine the effect of navigation on reaching diagnostic resolution at specific time points after an abnormal breast cancer screening test among a national sample. A prospective meta-analysis estimated the adjusted odds of achieving timely diagnostic resolution at 60, 180, and 365 days. Exploratory analyses were conducted on the pooled sample to identify which groups had the most benefit from navigation. Clinics from six medical centers serving vulnerable populations participated in the Patient Navigation Research Program. Women with an abnormal breast cancer screening test between 2007 and 2009 were included and received the patient navigation intervention or usual care. Patient navigators worked with patients and their care providers to address patient-specific barriers to care to prevent delays in diagnosis. A total of 4675 participants included predominantly racial/ethnic minorities (74 %) with public insurance (40 %) or no insurance (31 %). At 60 days and 180 days, there was no statistically significant effect of navigation on achieving timely diagnostic care, but a benefit of navigation was seen at 365 days (aOR 2.12, CI 1.36–3.29). We found an equal benefit of navigation across all groups, regardless of race/ethnicity, language, insurance status, and type of screening abnormality. Patient navigation resulted in more timely diagnostic resolution at 365 days among a diverse group of minority, low-income women with breast cancer screening abnormalities. PMID:27432417

Electron Flow in Multiheme Bacterial Cytochromes is a Balancing Act Between Heme Electronic Interaction and Redox Potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breuer, Marian; Rosso, Kevin M.; Blumberger, Jochen

The naturally widespread process of electron transfer from metal reducing bacteria to extracellular solid metal oxides entails unique biomolecular machinery optimized for long-range electron transport. To perform this function efficiently microorganisms have adapted multi-heme c-type cytochromes to arrange heme cofactors into wires that cooperatively span the cellular envelope, transmitting electrons along distances greater than 100 Angstroms. Implications and opportunities for bionanotechnological device design are self-evident. However, at the molecular level how these proteins shuttle electrons along their heme wires, navigating intraprotein intersections and interprotein interfaces effciently, remains a mystery so far inaccessible to experiment. To shed light on this criticalmore » topic, we carried out extensive computer simulations to calculate Marcus theory quantities for electron transfer along the ten heme cofactors in the recently crystallized outer membrane cytochrome MtrF. The combination of electronic coupling matrix elements with free energy calculations of heme redox potentials and reorganization energies for heme-to-heme electron transfer allows the step-wise and overall electron transfer rate to be estimated and understood in terms of structural and dynamical characteristics of the protein. By solving a master equation for electron hopping, we estimate an intrinsic, maximum possible electron flux through solvated MtrF of 104-105 s-1, consistent with recently measured rates for the related MtrCAB protein complex. Intriguingly, this flux must navigate thermodynamically uphill steps past low potential hemes. Our calculations show that the rapid electron transport through MtrF is the result of a clear correlation between heme redox potential and the strength of electronic coupling along the wire: Thermodynamically uphill steps occur only between electronically well connected stacked heme pairs. This suggests that the protein evolved to harbor low

Interaction Effects of Hypervideo Navigation Variables in College Students' Self-Regulated Learning

ERIC Educational Resources Information Center

Azmy, Nabil

2013-01-01

The purpose of this study is to investigate the question of whether the interaction effects of hypervideo navigation variables (navigation control and navigation links) would affect college students' self-regulated learning just after their learning from instructional hypervideo programs. Navigation control (free navigation or free navigation with…

Sensitivity of planetary cruise navigation to earth orientation calibration errors

NASA Technical Reports Server (NTRS)

Estefan, J. A.; Folkner, W. M.

1995-01-01

A detailed analysis was conducted to determine the sensitivity of spacecraft navigation errors to the accuracy and timeliness of Earth orientation calibrations. Analyses based on simulated X-band (8.4-GHz) Doppler and ranging measurements acquired during the interplanetary cruise segment of the Mars Pathfinder heliocentric trajectory were completed for the nominal trajectory design and for an alternative trajectory with a longer transit time. Several error models were developed to characterize the effect of Earth orientation on navigational accuracy based on current and anticipated Deep Space Network calibration strategies. The navigational sensitivity of Mars Pathfinder to calibration errors in Earth orientation was computed for each candidate calibration strategy with the Earth orientation parameters included as estimated parameters in the navigation solution. In these cases, the calibration errors contributed 23 to 58% of the total navigation error budget, depending on the calibration strategy being assessed. Navigation sensitivity calculations were also performed for cases in which Earth orientation calibration errors were not adjusted in the navigation solution. In these cases, Earth orientation calibration errors contributed from 26 to as much as 227% of the total navigation error budget. The final analysis suggests that, not only is the method used to calibrate Earth orientation vitally important for precision navigation of Mars Pathfinder, but perhaps equally important is the method for inclusion of the calibration errors in the navigation solutions.

Understanding the Social Navigation User Experience

ERIC Educational Resources Information Center

Goecks, Jeremy

2009-01-01

A social navigation system collects data from its users--its community--about what they are doing, their opinions, and their decisions, aggregates this data, and provides the aggregated data--community data--back to individuals so that they can use it to guide behavior and decisions. Social navigation systems empower users with the ability to…

Paediatric patient navigation models of care in Canada: An environmental scan.

PubMed

Luke, Alison; Doucet, Shelley; Azar, Rima

2018-05-01

(1) To provide other organizations with useful information when implementing paediatric navigation programs and (2) to inform the implementation of a navigation care centre in New Brunswick for children with complex health conditions. This environmental scan consisted of a literature review of published and grey literature for paediatric patient navigation programs across Canada. Additional programs were found following discussions with program coordinators and navigators. Interviews were conducted with key staff from each program and included questions related to patient condition; target population and location; method delivery; navigator background; and navigator roles. Data analysis included analysis of interviews and identification of common themes across the different programs. We interviewed staff from 19 paediatric navigation programs across Canada. Programs varied across a number of different themes, including: condition and disease type, program location (e.g., hospital or clinic), navigator background (e.g., registered nurse or peer/lay navigator) and method of delivery (e.g., phone or face-to-face). Overall, navigator roles are similar across all programs, including advocacy, education, support and assistance in accessing resources from both within and outside the health care system. This scan offers a road map of Canadian paediatric navigation programs. Knowledge learned from this scan will inform stakeholders who are either involved in the delivery of paediatric patient navigation programs or planning to implement such a program. Specifically, our scan informed the development of a navigation centre for children with complex health conditions in New Brunswick.

Autonomous satellite navigation using starlight refraction angle measurements

NASA Astrophysics Data System (ADS)

Ning, Xiaolin; Wang, Longhua; Bai, Xinbei; Fang, Jiancheng

2013-05-01

An on-board autonomous navigation capability is required to reduce the operation costs and enhance the navigation performance of future satellites. Autonomous navigation by stellar refraction is a type of autonomous celestial navigation method that uses high-accuracy star sensors instead of Earth sensors to provide information regarding Earth's horizon. In previous studies, the refraction apparent height has typically been used for such navigation. However, the apparent height cannot be measured directly by a star sensor and can only be calculated by the refraction angle and an atmospheric refraction model. Therefore, additional errors are introduced by the uncertainty and nonlinearity of atmospheric refraction models, which result in reduced navigation accuracy and reliability. A new navigation method based on the direct measurement of the refraction angle is proposed to solve this problem. Techniques for the determination of the refraction angle are introduced, and a measurement model for the refraction angle is established. The method is tested and validated by simulations. When the starlight refraction height ranges from 20 to 50 km, a positioning accuracy of better than 100 m can be achieved for a low-Earth-orbit (LEO) satellite using the refraction angle, while the positioning accuracy of the traditional method using the apparent height is worse than 500 m under the same conditions. Furthermore, an analysis of the factors that affect navigation accuracy, including the measurement accuracy of the refraction angle, the number of visible refracted stars per orbit and the installation azimuth of star sensor, is presented. This method is highly recommended for small satellites in particular, as no additional hardware besides two star sensors is required.

46 CFR 32.16-1 - Navigation bridge visibility-T/ALL.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Navigation bridge visibility-T/ALL. 32.16-1 Section 32..., AND HULL REQUIREMENTS Navigation Bridge Visibility § 32.16-1 Navigation bridge visibility-T/ALL. Each..., must meet the following requirements: (a) The field of vision from the navigation bridge, whether the...

Autonomous Navigation for Deep Space Missions

NASA Technical Reports Server (NTRS)

Bhaskaran, Shyam

2012-01-01

Navigation (determining where the spacecraft is at any given time, controlling its path to achieve desired targets), performed using ground-in- the-loop techniques: (1) Data includes 2-way radiometric (Doppler, range), interferometric (Delta- Differential One-way Range), and optical (images of natural bodies taken by onboard camera) (2) Data received on the ground, processed to determine orbit, commands sent to execute maneuvers to control orbit. A self-contained, onboard, autonomous navigation system can: (1) Eliminate delays due to round-trip light time (2) Eliminate the human factors in ground-based processing (3) Reduce turnaround time from navigation update to minutes, down to seconds (4) React to late-breaking data. At JPL, we have developed the framework and computational elements of an autonomous navigation system, called AutoNav. It was originally developed as one of the technologies for the Deep Space 1 mission, launched in 1998; subsequently used on three other spacecraft, for four different missions. The primary use has been on comet missions to track comets during flybys, and impact one comet.

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Laboratory complex for simulation of navigation signals of pseudosatellites

NASA Astrophysics Data System (ADS)

Ratushniak, V. N.; Gladyshev, A. B.; Sokolovskiy, A. V.; Mikhov, E. D.

2018-05-01

In the article, features of the organization, structure and questions of formation of navigation signals of pseudosatellites of the short - range navigation system based on the hardware-software complex National Instruments are considered. A software model that performs the formation and management of a pseudo-random sequence of a navigation signal and the formation and management of the format transmitted pseudosatellite navigation information is presented. The variant of constructing the transmitting equipment of the pseudosatellite base stations is provided.

A novel navigation method used in a ballistic missile

NASA Astrophysics Data System (ADS)

Qian, Hua-ming; Sun, Long; Cai, Jia-nan; Peng, Yu