WorldWideScience

Sample records for aids to navigation

  1. 33 CFR 66.10-15 - Aids to navigation.

    Science.gov (United States)

    2010-07-01

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

  2. 33 CFR 67.35-10 - Private aids to navigation.

    Science.gov (United States)

    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 §...

  3. A wayfinding aid to increase navigator independence

    Directory of Open Access Journals (Sweden)

    Wilfred Waters

    2011-12-01

    Full Text Available Wayfinding aids are of great benefit because users do not have to rely on their learned geographic knowledge or orientation skills alone for successful navigation. Additionally, cognitive resources usually captured by this activity can be spent elsewhere. A challenge, however, remains for wayfinding aid developers. Due to the automation of wayfinding aids, navigator independence may be decreasing via the use of these aids. In order to address this, wayfinding aids might be improved additionally to perform a training role. Since the most versatile wayfinders appear to deploy a dual strategy for geographic orientation, it is proposed that wayfinding aids be improved to foster such an approach. This paper presents the results of an experimental study testing a portion of the suggested enhancement.

  4. 33 CFR 100.45 - Establishment of aids to navigation.

    Science.gov (United States)

    2010-07-01

    ... 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... navigation. The District Commander will establish and maintain only those aids to navigation necessary...

  5. 33 CFR 66.01-50 - Protection of private aids to navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Protection of private aids to navigation. 66.01-50 Section 66.01-50 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State §...

  6. 75 FR 8390 - St. Croix River Aids to Navigation

    Science.gov (United States)

    2010-02-24

    ... Federal Register (73 FR 3316). Information on Services for Individuals With Disabilities For information... SECURITY Coast Guard St. Croix River Aids to Navigation AGENCY: Coast Guard, DHS. ACTION: Notice of public... the aids to navigation in the St. Croix River. DATES: A public meeting will be held on Tuesday,...

  7. 46 CFR 4.05-20 - Report of accident to aid to navigation.

    Science.gov (United States)

    2010-10-01

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

  8. 46 CFR 131.910 - Notices to mariners and aids to navigation.

    Science.gov (United States)

    2010-10-01

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

  9. 46 CFR 122.230 - Report of accident to aid to navigation.

    Science.gov (United States)

    2010-10-01

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

  10. 46 CFR 185.230 - Report of accident to aid to navigation.

    Science.gov (United States)

    2010-10-01

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

  11. 76 FR 77585 - Notice to Manufacturers of Airport Lighting and Navigation Aid Equipment

    Science.gov (United States)

    2011-12-13

    ... Federal Aviation Administration Notice to Manufacturers of Airport Lighting and Navigation Aid Equipment... lighting and navigation aid equipment. SUMMARY: Projects funded under the Airport Improvement Program (AIP... navigation aid equipment that is lit with Light Emitting Diode (LED) lighting. This notice...

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Davide O. Nitti

    2015-07-01

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

  14. 46 CFR 167.65-45 - Notice to mariners; aids to navigation.

    Science.gov (United States)

    2010-10-01

    ... United States vessels in one or on the navigable waters of the United States, see 33 CFR 164.33. ... 46 Shipping 7 2010-10-01 2010-10-01 false Notice to mariners; aids to navigation. 167.65-45... navigation. (a) Officers are required to acquaint themselves with the latest information published by...

  15. Florida coastal Aids to Navigation GIS data in 2001 (NODC Accession 0000599)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The term Aids to Navigation (ATONS or AIDS) refers to a device outside of a vessel used to assist mariners in determining their position or safe course, or to warn...

  16. 33 CFR 401.54 - Interference with navigation aids.

    Science.gov (United States)

    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)...

  17. Responding to PEPFAR - How NGOs navigate aid conditionalities

    OpenAIRE

    Thomsen, Stine Skoett

    2007-01-01

    This dissertation sets out to explore how two Ugandan NGOs, the Straight Talk Foundation and the Family Planning Association of Uganda have responded to and negotiated with the President’s Emergency Plan for AIDS Relief (PEPFAR). Ascertaining a conflictual relation between the rights-based approach to HIV prevention for young people of the two NGO and the value-based approach by PEPFAR, it is demonstrated that this contradiction can to some degree be prevailed over through negotiation, assimi...

  18. Real-time Risk Assessment for Aids to Navigation Using Fuzzy-FSA on Three-Dimensional Simulation System

    Directory of Open Access Journals (Sweden)

    Jinbiao Chen

    2014-06-01

    Full Text Available The risk level of the Aids to Navigation (AtoNs can reflect the ship navigation safety level in the channel to some extent. In order to appreciate the risk level of the aids to navigation (AtoNs in a navigation channel and to provide some decision-making suggestions for the AtoNs Maintenance and Management Department, the risk assessment index system of the AtoNs was built considering the advanced experience of IALA. Under the Formal Safety Assessment frame, taking the advantages of the fuzzy comprehensive evaluation method, the fuzzy-FSA model of risk assessment for aids to navigation was established. The model was implemented for the assessment of aids to navigation in Shanghai area based on the aids to navigation three-dimensional simulation system. The real-time data were extracted from the existing information system of aids to navigation, and the real-time risk assessment for aids to navigation of the chosen channel was performed on platform of the three-dimensional simulation system, with the risk assessment software. Specifically, the deep-water channel of the Yangtze River estuary was taken as an example to illustrate the general assessment procedure. The method proposed presents practical significance and application prospect on the maintenance and management of the aids to navigation.

  19. 75 FR 998 - Terminate Long Range Aids to Navigation (Loran-C) Signal

    Science.gov (United States)

    2010-01-07

    ... necessary, the Department of Homeland Security will complete an analysis of potential backups to GPS. The... FR 4047), the U.S. Coast Guard began a public review process for its Draft Programmatic Environmental... SECURITY Coast Guard Terminate Long Range Aids to Navigation (Loran-C) Signal AGENCY: U.S. Coast Guard,...

  20. Nautical Navigation Aids (NAVAID) Locations

    Data.gov (United States)

    Department of Homeland Security — Structures intended to assist a navigator to determine position or safe course, or to warn of dangers or obstructions to navigation. This dataset includes lights,...

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

    Directory of Open Access Journals (Sweden)

    Fang Tae Hyun

    2015-05-01

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

  2. 33 CFR 209.325 - Navigation lights, aids to navigation, navigation charts, and related data policy, practices and...

    Science.gov (United States)

    2010-07-01

    ... greater (ENG Form 4020-R). (ii) For channels 100 to 400 feet wide (ENG Form 4021-R). Name of channel Date... Channel 3-78 300 1.14 26 24 23 26 Whitehall Channel 3-78 200 1.81 26 27 26 25 ENG FORM 4021-R (Jul...

  3. Aids to Navigation for US waters, including territories, as of April 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Structures intended to assist a navigator to determine position or safe course, or to warn of dangers or obstructions to navigation. This dataset includes lights,...

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

    Directory of Open Access Journals (Sweden)

    Stephen L Hicks

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

  5. Way-marking behaviour: an aid to spatial navigation in the wood mouse (Apodemus sylvaticus

    Directory of Open Access Journals (Sweden)

    Stopka Pavel

    2003-04-01

    solely as an aid to spatial navigation during exploration.

  6. On the use of SAR interferometry to aid navigation of UAV

    Science.gov (United States)

    Nitti, Davide O.; Bovenga, Fabio; Morea, Alberto; Rana, Fabio M.; Guerriero, Luciano; Greco, Mario; Pinelli, Gianpaolo

    2012-09-01

    This study is aimed at exploring the potentials of SAR Interferometry (InSAR) to aid Unmanned Aerial Vehicles (UAV) navigation. The basic idea is to infer both position and attitude of an aerial platform by inspecting the InSAR phase derived by a real time SAR interferometer mounted onboard the platform. Thanks to the expected favorable conditions in terms of geometrical sensitivity as well as signal coherence, the InSAR phase field can be used to derive the terrain elevation. By using both approximated position and attitude values of the platform as well as a reference Digital Terrain Model (DTM) from a mission database available onboard, it is possible to generate a synthetic InSAR phase model to be compared w.r.t. that derived by SAR observations. The geometrical transformation needed to match these two terrain models depends on the difference between position and attitude values derived by the instruments available on board and their actual values. Hence, this matching provides a feedback to be used for adjusting position and attitude. In order to assess the reliability of the proposed approach, we evaluated the interferometric sensitivity to changes in position and attitude. This analysis defines the limits of applicability of the InSAR-based approach and provides indications and requirements on geometric and radiometric parameters.

  7. Blavigator: a navigation aid for blind persons

    OpenAIRE

    José, João; MORENO, M; Pinilla-Dutoit, J.; Rodrigues, J. M. F.; du Buf, J. M. H.

    2012-01-01

    Blavigator (blind navigator) is a vision aid for blind and visuaIIy impaired persons. It supports local navigation by detecting waIkable paths in the immediate vicinity of the user. It guides the user for centering on the path.

  8. Navigation aided surgery for facial fractures

    International Nuclear Information System (INIS)

    A navigation system that has been developed in neurosurgery has recently been applied in the maxillofacial region. We introduced a navigation system (Stealth Station, Medtronic) in the maxillofacial region. As preoperative preparation, CT scanning was performed with a slice of 1 mm. Navigation aided surgery was performed in 11 patients with facial fractures between April 2005 and July 2006. Navigation aided reduction of the bone segment was performed by comparing with the sound site on the screen. Facial symmetry was recovered in 10 of 11 cases. Facial asymmetry in 1 case (midfacial multiple fractures) remained, because the system did not work after the surgeon contacted the reference frame during the operation. The navigation system is useful for repairing facial fractures, especially for verifying facial symmetry. (author)

  9. Cognitive Costs of Navigation Aids in Hypermedia Learning

    Science.gov (United States)

    Waniek, Jacqueline; Ewald, Karolin

    2008-01-01

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

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

    Science.gov (United States)

    Jakel, Thomas

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

  11. Computer Navigation-aided Resection of Sacral Chordomas

    Directory of Open Access Journals (Sweden)

    Yong-Kun Yang

    2016-01-01

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

  12. 75 FR 997 - Record of Decision (ROD) on the U.S. Coast Guard Long Range Aids to Navigation (Loran-C) Program

    Science.gov (United States)

    2010-01-07

    ... announced by the Environmental Protection Agency (EPA) on June 12, 2009 (74 FR 28046). DATES: The Final PEIS... ``USCG Long Range Aids to Navigation (Loran-C) Program'' Web site at http://loranpeis.uscg.e2m-inc.com... 24 monitoring sites. On January 22, 2009 (74 FR 4047), the USCG made available the Draft PEIS....

  13. Navigating the AIDS industry: being poor and positive in Tanzania.

    Science.gov (United States)

    Boesten, Jelke

    2011-01-01

    This article shows how poor people living with HIV/AIDS in Tanzania navigate a myriad of actors, agencies and organizations to obtain the aid they need to survive. It focuses on community-based organizations which establish networks of care through which people obtain care, treatment and financial support. A case study of a roadside town in Tanzania illustrates that these community-based networks of care — essential to the survival of many — are partly the product of the AIDS industry, which encourages the establishment of community-based organizations and voluntary service delivery rather than more formalized systems of care. Community-based organizations, however, are so poorly supported that they often deploy self-destructive strategies. The need to strategically navigate the AIDS industry creates tension and even conflict among HIV-positive activists, the people they represent and the wider community, which undermines rather than strengthens community-based interventions. Whilst the AIDS industry promises inclusion of HIV-positive people in the response to HIV/AIDS, it succeeds only partially, with the result that it may potentially do more harm than good. PMID:22069802

  14. A Visual-aided Inertial Navigation and Mapping System

    OpenAIRE

    Munguía, Rodrigo; Nuño, Emmanuel; Aldana, Carlos I.; Urzua, Sarquis

    2016-01-01

    State estimation is a fundamental necessity for any application involving autonomous robots. This paper describes a visual-aided inertial navigation and mapping system for application to autonomous robots. The system, which relies on Kalman filtering, is designed to fuse the measurements obtained from a monocular camera, an inertial measurement unit (IMU) and a position sensor (GPS). The estimated state consists of the full state of the vehicle: the position, orientation, their first derivati...

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

    Science.gov (United States)

    Kuzu, Abdullah; Firat, Mehmet

    2010-01-01

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

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

    Science.gov (United States)

    Morrison, Jamie R.

    plate aperture produces diffraction patterns that change the shape of the focal blur pattern. When used as an aperture, the Fresnel zone plate produces multiple focal planes in the scene. The interference between the multiple focal planes produce changes in the aperture that can be observed both between the focal planes and beyond the most distant focal plane. The Fresnel zone plate aperture and lens may be designed to change in the focal blur pattern at greater depths, thereby improving measurement performance of the coded aperture system. This research provides an in-depth study of the Fresnel zone plate used as a coded aperture, and the performance improvement obtained by augmenting a single camera vision aided inertial navigation system with a Fresnel zone plate coded aperture. Design and analysis of a generalized coded aperture is presented and demonstrated, and special considerations for the Fresnel zone plate are given. Also techniques to determine a continuous depth measurement from a coded image are presented and evaluated through measurement. Finally the measurement results from different aperture configurations are statistically modeled and compared with a simulated vision aided navigation environment to predict the change in performance of a vision aided inertial navigation system when augmented with a coded aperture.

  17. Computer aided planning and navigation for orbito-zygomatic reconstruction

    CERN Document Server

    Marecaux, Christophe; Payan, Yohan; Boutault, Franck

    2007-01-01

    This paper suggests a full protocol of Computer Aided Surgery as previously recommended in literature addressing the challenging task of primary or secondary reconstruction of orbito-zygomatic dislocation. First, on a specifically developed planning software, the best zygoma reduction and orbital boundaries reconstruction to achieve skeletal symmetry are determined. This treatment plan is then transferred to the 3D Navigation Systems within the operating room. After patient's anatomy registration to his preoperative CT scan data, the navigation system allows zygomatic guiding to its planned reduced location and bone orbital volume restoration control. The feasibility of this technique was checked in 3 patients with major orbito-zygomatic deformities. Preliminary clinical results are presented.

  18. DETERMINING THE NAVIGATIONAL AIDS USE ON THE INTERNET: The Information Technologies Teacher Candidates’ Case

    Directory of Open Access Journals (Sweden)

    Abdullah KUZU

    2010-07-01

    Full Text Available The Internet users who fail to cope with navigation may generally face various problems such as disorientation, distraction, low motivation and abondenment of information retrieval. Therefore, navigational aids are frequently used in today’s Web browsers and Web sites to help users navigate on the Internet. However, it is asserted that navigational aids are still not thoroughly understood and effectively used by Information Technologies Teacher candidates. The purpose of this research is, therefore, to determine the navigational aids use by Information Technologies Candidate Teachers during information retrieval process on the Internet. A three-section survey was developed for this purpose. In this survey research, Information Technologies Teacher Candidates’ use of navigational aids in Web sites and Web browsers, and the reasons for low use of navigational aids were investigated. The findings of the study revealed that the teacher candidates did not use bookmarks, Web maps, RSS and atom feeds sufficiently. Moreover, it was found out that the use of navigational aids by teacher candidates show variations according to the average Internet use.

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

    Science.gov (United States)

    Bayoud, Fadi; Skaloud, Jan

    2008-04-01

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

  20. CEGB intergraph computer aided design system as an aid for the navigation of remote manipulators

    International Nuclear Information System (INIS)

    Computer Aided Design Systems with 3D Graphic capability can offer substantial benefits for the simulation and navigation of remote manipulators. The CEGB has been experimenting with its own Corporate INTERGRAPH CAD Network using as an example a remote links manipulator working within the above gas baffle dome area of an Advanced Gas Cooled Reactor. A report of this work is presented together with graphic simulations of the manipulator within the above dome area and reconstructions of images anticipated from the on board cameras. Future improvements in the speed of graphic processing will enable these techniques to be used for the on-line navigation of manipulators, as an aid to the interpretation of video images and for the training of operators without the need for full size test and training facilities. (author)

  1. A Visual-aided Inertial Navigation and Mapping System

    Directory of Open Access Journals (Sweden)

    Rodrigo Munguía

    2016-05-01

    Full Text Available State estimation is a fundamental necessity for any application involving autonomous robots. This paper describes a visual-aided inertial navigation and mapping system for application to autonomous robots. The system, which relies on Kalman filtering, is designed to fuse the measurements obtained from a monocular camera, an inertial measurement unit (IMU and a position sensor (GPS. The estimated state consists of the full state of the vehicle: the position, orientation, their first derivatives and the parameter errors of the inertial sensors (i.e., the bias of gyroscopes and accelerometers. The system also provides the spatial locations of the visual features observed by the camera. The proposed scheme was designed by considering the limited resources commonly available in small mobile robots, while it is intended to be applied to cluttered environments in order to perform fully vision-based navigation in periods where the position sensor is not available. Moreover, the estimated map of visual features would be suitable for multiple tasks: i terrain analysis; ii three dimensional (3D scene reconstruction; iii localization, detection or perception of obstacles and generating trajectories to navigate around these obstacles; and iv autonomous exploration. In this work, simulations and experiments with real data are presented in order to validate and demonstrate the performance of the proposal.

  2. Development of a robotic mobile mapping system by vision-aided inertial navigation: a geomatics approach

    OpenAIRE

    Bayoud, Fadi Atef; Merminod, Bertrand

    2007-01-01

    Vision-based inertial-aided navigation is gaining ground due to its many potential applications. In previous decades, the integration of vision and inertial sensors was monopolised by the defence industry due to its complexity and unrealistic economic burden. After the technology advancement, high-quality hardware and computing power became reachable for the investigation and realisation of various applications. In this thesis, a mapping system by vision-aided inertial navigation was develope...

  3. Airborne laser scanner aided inertial for terrain referenced navigation in unknown environments

    Science.gov (United States)

    Vadlamani, Ananth Kalyan

    A dead-reckoning terrain referenced navigation (TRN) system that uses airborne laser ranging sensors to aid an aircraft inertial navigation system (INS) is presented. Improved navigation performance is achieved through estimation of vehicle velocity and position using terrain measurements. The system only uses aircraft sensors and simultaneously performs the dual functions of mapping and navigation in unknown environments. The theory, algorithms and results of the system performance are presented using simulations and flight test data. This dissertation focuses primarily on the use of dual airborne laser scanners (ALS) for aiding an INS. Dual ALS measurements are used to generate overlapping terrain models, which are then used to estimate the INS velocity and position errors and constrain its drift. By keeping track of its errors, a navigation-grade INS is aided in a feed-forward manner. This dead-reckoning navigation algorithm is generic enough to be easily extendable to use other optical sensors. Data integrity, sensor alignment and the effects of vegetation noise, attitude and heading accuracy are analyzed. Furthermore, a feedback coupled aiding scheme is presented in which a tactical-grade inertial measurement unit (IMU) is aided with dual ALS measurements by feeding the estimated velocity back into the IMU computations. The proposed system can potentially serve as a backup during temporary Global Positioning System (GPS) signal outages, or it can be used to coast for extended periods of time. Although it has elements of conventional TRN, this system does not require a terrain database since its in-flight mapping capability generates the terrain data for navigation. Hence, the system can be used in both non-GPS as well as unknown terrain environments. The navigation system is dead-reckoning in nature and errors accumulate over time, unless the system can be reset periodically by geo-referenced terrain data or a position estimate from another navigation aid.

  4. Accuracy Evaluation of Stereo Vision Aided Inertial Navigation for Indoor Environments

    Science.gov (United States)

    Griessbach, D. G.; Baumbach, D. B.; Boerner, A. B.; Zuev, S. Z.

    2013-11-01

    Accurate knowledge of position and orientation is a prerequisite for many applications regarding unmanned navigation, mapping, or environmental modelling. GPS-aided inertial navigation is the preferred solution for outdoor applications. Nevertheless a similar solution for navigation tasks in difficult environments with erroneous or no GPS-data is needed. Therefore a stereo vision aided inertial navigation system is presented which is capable of providing real-time local navigation for indoor applications. A method is described to reconstruct the ego motion of a stereo camera system aided by inertial data. This, in turn, is used to constrain the inertial sensor drift. The optical information is derived from natural landmarks, extracted and tracked over consequent stereo image pairs. Using inertial data for feature tracking effectively reduces computational costs and at the same time increases the reliability due to constrained search areas. Mismatched features, e.g. at repetitive structures typical for indoor environments are avoided. An Integrated Positioning System (IPS) was deployed and tested on an indoor navigation task. IPS was evaluated for accuracy, robustness, and repeatability in a common office environment. In combination with a dense disparity map, derived from the navigation cameras, a high density point cloud is generated to show the capability of the navigation algorithm.

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

    Directory of Open Access Journals (Sweden)

    Yan Li

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  7. [Navigation aid through the information overload].

    Science.gov (United States)

    Günther, Judith; Schindler, Birgit; Suter, Katja

    2014-10-01

    We live in the modern information society. "To be informed" has a crucial impact on the personal, professional, economic and social development. The knowledge of things and their relationships is essential for acute decisions as well as for long-term planning. And at no time it was easier to get the information required within shorter time periods--no matter to whatsoever. The offer of information of the World Wide Web is inexhaustible. This also applies to information about all possible therapeutic and pharmaceutical issues. But is the information found reliable, too? And are easily accessible sources credible? Can we deal with the information overload at these days or do we actually risk paddling only on the surface of the "information-sea", without ever perceiving the actual information depth and width, less to use it? How can we protect being taken in by marketing strategies? The present article describes a structured proceed when seeking literature to find useful medical and pharmaceutical information in a time saving manner. PMID:25632609

  8. A Toolbox of Aiding Techniques for the HUGIN AUV Integrated Inertial Navigation System

    Directory of Open Access Journals (Sweden)

    Bjørn Jalving

    2004-07-01

    Full Text Available Modern AUV designs must handle submerged autonomous operation for long periods of time. The state of the art solution embedded in the HUGIN AUVs is a Doppler Velocity Log (DVL aided Inertial Navigation System (INS that can integrate various forms of position measurement updates. In autonomous operations, position updates are only available in limited periods of time or space, thus the core velocity aided inertial navigation system must exhibit high accuracy However, position uncertainty of a DVL aided inertial navigation system will eventually drift off, compromising either mission operation or requirements for accurate positioning of payload data. To meet the requirements for a range of military and civilian AUV applications, the HUGIN vehicles come with a flexible and powerful set of navigation techniques. Methods for position updates include GPS surface fix, DGPS-USBL, Underwater Transponder Positioning (UTP and bathymetric terrain navigation. Based on synthetic aperture sonar technology, a potentially revolutionary accurate velocity measurement is under development. HUGIN also comes with a navigation post-processing system (NavLab, which can be applied to increase navigational integrity and maximize position accuracy.

  9. Model-aided Navigation with Sea Current Estimation for an Autonomous Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Alain Martinez

    2015-07-01

    Full Text Available This paper presents a strategy to improve the navigation solution of the HRC-AUV by deploying a model-aided inertial navigation system (MA-INS. Based on a simpler three-DOF linear dynamic model (DM of the vehicle, and implemented through a Kalman filter (KF, the performance of the proposed MA-INS is compared to state-of-the-art solutions based on non-linear models. The model allows the online estimation of the sea current parameters before and during the navigation mission. Qualitative and quantitative evaluations as well as a statistical significance test are performed using both simulated and real data, demonstrating the usefulness of the proposed model-aided navigation.

  10. Ultrasound-Aided Pedestrian Dead Reckoning for Indoor Navigation

    NARCIS (Netherlands)

    Fischer, C.; Muthukrishnan, K.; Hazas, M.; Gellersen, H.

    2008-01-01

    Ad hoc solutions for tracking and providing navigation support to emergency response teams is an important and safety-critical challenge. We propose a navigation system based on a combination of foot-mounted inertial sensors and ultrasound beacons. We evaluate experimentally the performance of our

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

    OpenAIRE

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

    2015-01-01

    A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. Th...

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

    Science.gov (United States)

    Zhou, Ling; Cheng, Xianghong; Zhu, Yixian

    2016-09-01

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

  13. Model-aided Navigation with Sea Current Estimation for an Autonomous Underwater Vehicle

    OpenAIRE

    Alain Martinez; Luis Hernandez; Hichem Sahli; Yunier Valeriano-Medina; Maykel Orozco-Monteagudo; Delvis Garcia-Garcia

    2015-01-01

    This paper presents a strategy to improve the navigation solution of the HRC-AUV by deploying a model-aided inertial navigation system (MA-INS). Based on a simpler three-DOF linear dynamic model (DM) of the vehicle, and implemented through a Kalman filter (KF), the performance of the proposed MA-INS is compared to state-of-the-art solutions based on non-linear models. The model allows the online estimation of the sea current parameters before and during the navigation mission. Qualitative and...

  14. The Performance Analysis of the Tactical Inertial Navigator Aided by Non-GPS Derived References

    Directory of Open Access Journals (Sweden)

    Kai-Wei Chiang

    2014-12-01

    Full Text Available The Inertial Navigation System (INS is now widely applied in many navigation and mobile mapping applications due to its high sampling rates, high accuracy in short-term cases, and no limitations caused by interference or signal obstructions. In addition, the INS can continuously provide the position, velocity and attitude of a vehicle. Conversely, the disadvantage of the stand-alone INS is that its accuracy degrades rapidly with time because of the accumulations of systematic errors and noises from accelerometers and gyroscopes. Therefore, this research aims to implement an integrated system with specific 3D position updates using non-GPS derived references to aid a tactical inertial navigator to provide seamless navigation solutions in the specific area without Global Positioning System (GPS signals. An Extended Kalman Filter (EKF is applied as the core estimator to provide superior performance and output the navigation solutions in real-time. The INS is updated by position from references such as the digital map, land mark, Digital Terrain Model (DTM as well as waypoint to improve navigation accuracy in the long-term. In order to evaluate the performance of the proposed algorithm, field tests including land scenario in freeway and airborne scenario with an unmanned aerial test platform have been conducted. The preliminary results demonstrate that the proposed algorithm with non-GPS derived references aiding from digital map and waypoint for onboard aerial camera trigger to provide uninterrupted navigation solutions and better performance which can achieve the meter-level accuracy without GPS aiding for land and aerial scenarios, respectively.

  15. Finger Movement Based Wearable Communication & Navigation Aid for partially disabled

    Directory of Open Access Journals (Sweden)

    Jobin Jose

    2016-02-01

    Full Text Available The FMBWCN Aid is a portable and wearable multi-purpose system for the partially disabled. The Aid is a glove-based system in which different trained finger movements leads to different modes of operation of the system such as APR Voice Module and Wheelchair Controller Module. The finger movements (bending movement leads to the flexion of the flex sensor attached to the glove. Flexion leads to change in resistance of the flex sensors, which will be recorded via a microcontroller (Arduino Uno and different sets of movement of the fingers will lead to different modules of operation as specified in the default settings of the FMBWCN Aid.

  16. Cancer-related electronic support groups as navigation-aids: Overcoming geographic barriers

    OpenAIRE

    Till, James E

    2004-01-01

    Cancer-related electronic support groups (ESGs) may be regarded as a complement to face-to-face groups when the latter are available, and as an alternative when they are not. Advantages over face-to-face groups include an absence of barriers imposed by geographic location, opportunities for anonymity that permit sensitive issues to be discussed, and opportunities to find peers online. ESGs can be especially valuable as navigation aids for those trying to find a way through the healthcare syst...

  17. A SWITCHED-ANTENNA NADIR-LOOKING INTERFEROMETRIC SAR ALTIMETER FOR TERRAIN-AIDED NAVIGATION

    OpenAIRE

    Inchan Paek; Jonghun Jang; Joohwan Chun; Jinbae Suh

    2016-01-01

    Conventional terrain-aided navigation (TAN) technique uses an altimeter to locate the position of an aerial vehicle. However, a major problem with a radar altimeter is that its beam (or pulse) footprint on the ground could be large, and therefore the nadir altitude cannot be estimated accurately. To overcome this difficulty, one may use the nadir-looking synthetic aperture radar (SAR) technique to reduce the along-track beam width, while the cross-track ambiguity is resolved wi...

  18. Computer vision as a navigation aid for visually impaired

    OpenAIRE

    MARKOČIČ, JAN

    2015-01-01

    Accomplishing many of the every-day activities present a significant challenge to visually impaired people. One of such challenges is navigation in an unsupervised environment, which might be well addressed with technological solutions. The recent technological advances have made computational devices with significant processing power a widely affordable commodity. In parallel, the advances in computer-vision-based systems allow scene reconstruction in real time paving the way for realistic s...

  19. The Vector Matching Method in Geomagnetic Aiding Navigation.

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  1. High-Precision Image Aided Inertial Navigation with Known Features: Observability Analysis and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Weiping Jiang

    2014-10-01

    Full Text Available A high-precision image-aided inertial navigation system (INS is proposed as an alternative to the carrier-phase-based differential Global Navigation Satellite Systems (CDGNSSs when satellite-based navigation systems are unavailable. In this paper, the image/INS integrated algorithm is modeled by a tightly-coupled iterative extended Kalman filter (IEKF. Tightly-coupled integration ensures that the integrated system is reliable, even if few known feature points (i.e., less than three are observed in the images. A new global observability analysis of this tightly-coupled integration is presented to guarantee that the system is observable under the necessary conditions. The analysis conclusions were verified by simulations and field tests. The field tests also indicate that high-precision position (centimeter-level and attitude (half-degree-level-integrated solutions can be achieved in a global reference.

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

    Science.gov (United States)

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

    2015-01-01

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

  3. Analysis of a clock-aided global navigation satellite system (GNSS)

    International Nuclear Information System (INIS)

    This paper presents a dilution of precision (DOP) analysis of a clock-aided global navigation satellite system (GNSS). Firstly, the analysis shows that a best linear unbiased estimator should be used in the clock-aided GNSS to get the best improvements in accuracy. Secondly, the influence of the clock on vertical DOP (VDOP) and horizontal DOP (HDOP) is analysed by using the clock characteristics as a weighting matrix. The analysis highlights quantitative improvements in the VDOP and HDOP and explains why improvements in the VDOP are superior to those of the HDOP in the clock-aided GNSS. Finally, the paper analyses how incorrectly known a priori clock variances degrade the level of accuracy and offers guidelines for determining a weighting matrix in the cases where the clock characteristics are not clearly known

  4. A linguistic and navigational knowledge approach to text navigation

    OpenAIRE

    Couto, Javier; Minel, Jean-Luc

    2008-01-01

    We present an approach to text navigation conceived as a cognitive process exploiting linguistic information present in texts. We claim that the navigational knowledge in-volved in this process can be modeled in a declarative way with the Sextant language. Since Sextant refers exhaustively to specific linguistic phenomena, we have defined a customized text representation. These dif-ferent components are implemented in the text navigation system NaviTexte. Two ap-plications of NaviTexte are de...

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

    Science.gov (United States)

    Song, Ziqi; Bian, Hongyu; Zielinski, Adam

    2015-12-01

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

  6. Underwater Terrain-Aided Navigation Based on Multibeam Bathymetric Sonar Images

    Institute of Scientific and Technical Information of China (English)

    Ziqi Song; Hongyu Bian; Adam Zielinski

    2015-01-01

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

  7. DVL Velocity Aiding in the HUGIN 1000 Integrated Inertial Navigation System

    Directory of Open Access Journals (Sweden)

    Bjørn Jalving

    2004-10-01

    Full Text Available The RDI WHN-600 Doppler Velocity Log (DVL is a key navigation sensor for the HUG1N 1000 Autonomous Underwater Vehicle (AUV. HUGIN 1000 is designed for autonomous submerged operation for long periods of time. This is facilitated by a low drift velocity aided Inertial Navigation System (INS. Major factors determining the position error growth are the IMU and DVL error characteristics and the mission plan pattern_ For instance, low frequency DVL errors cause an approximately linear drift in a straight-line trajectory, while these errors tend to be cancelled out by a lawn mower pattern_ The paper focuses on the accuracy offered by the DVL. HUGIN 1000 is a permanent organic mine countermeasure (MCM capacity on the Royal Norwegian Navy MCM vessel KNM Karmoy. HUGIN 1000 will be part of the NATO force MCMFORNORTH in fall 2004.

  8. WiFi-Aided Magnetic Matching for Indoor Navigation with Consumer Portable Devices

    OpenAIRE

    You Li; Yuan Zhuang; Haiyu Lan; Peng Zhang; Xiaoji Niu; Naser El-Sheimy

    2015-01-01

    This paper presents a WiFi-aided magnetic matching (MM) algorithm for indoor pedestrian navigation with consumer portable devices. This algorithm reduces both the mismatching rate (i.e., the rate of matching to an incorrect point that is more than 20 m away from the true value) and computational load of MM by using WiFi positioning solutions to limit the MM search space. Walking tests with Samsung Galaxy S3 and S4 smartphones in two different indoor environments (i.e., Environment #1 with abu...

  9. Integration of GPS and low cost INS for pedestrian navigation aided by building layout

    Institute of Scientific and Technical Information of China (English)

    Feng Wenquan; Zhao Hongbo; Zhao Qi; Li Jingwen

    2013-01-01

    In outdoor environments, GPS is often used for pedestrian navigation by utilizing its sig-nals for position computation, but in indoor or semi-obstructed environments, GPS signals are often unavailable. Therefore, pedestrian navigation for these environments should be realized by the integration of GPS and inertial navigation system (INS). However, the lowcost INS could induce errors that may result in a large position drift. The problem can be minimized by mounting the sensors on the pedestrian’s foot, using zero velocity update (ZUPT) method with the standard navigation algorithm to restrict the error growth. However, heading drift still remains despite using ZUPT measurements since the heading error is unobservable. Also, foot mounted INS suffers from the initialization ambiguity of position and heading from GPS. In this paper, a novel algorithm is developed to mitigate the heading drift problem when using ZUPT. The method uses building lay-out to aid the heading measurement in Kalman filter, and it could also be combined for the initial-ization. The algorithm has been investigated with real field trials using the low cost Microstrain 3DM-GX3-25 inertial sensor, a Leica GS10 GPS receiver and a uBlox EVK-6T GPS receiver. It could be concluded that the proposed method offers a significant improvement in position accuracy for the long period, allowing pedestrian navigation for nearly40 min with mean position error less than 2.8 m. This method also has a considerable effect on the accuracy of the initialization.

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

    Science.gov (United States)

    Morozov, Andrew

    2009-01-01

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

  11. How to Get Hearing Aids

    Science.gov (United States)

    ... Consumer Products Hearing Aids How to get Hearing Aids Share Tweet Linkedin Pin it More sharing options ... my hearing aids? How do I get hearing aids? To get hearing aids, you should first have ...

  12. A greedy-navigator approach to navigable city plans

    CERN Document Server

    Lee, Sang Hoon

    2012-01-01

    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 m...

  13. Supporting Tools to Simplify the Navigation Process over the Web

    OpenAIRE

    Chabane Khentout; Mahieddine Djoudi; Lamri Douidi

    2006-01-01

    We Navigation through the Web has problems of positioning and space-temporal reference marks. Therefore, its necessary to design some computer-aided tools to help the user to position himself in space and time during a navigation session. The user is provided with a map of visited sites, thus giving an explicit representation of virtual space. Various levels of visualization are set up to make the map more visible and less overloaded. A permanently displayed time indicator enables users to ke...

  14. Supporting Tools to Simplify the Navigation Process over the Web

    Directory of Open Access Journals (Sweden)

    Chabane Khentout

    2006-01-01

    Full Text Available We Navigation through the Web has problems of positioning and space-temporal reference marks. Therefore, it’s necessary to design some computer-aided tools to help the user to position himself in space and time during a navigation session. The user is provided with a map of visited sites, thus giving an explicit representation of virtual space. Various levels of visualization are set up to make the map more visible and less overloaded. A permanently displayed time indicator enables users to keep an eye on themselves and thus to optimize navigation time.

  15. WiFi-Aided Magnetic Matching for Indoor Navigation with Consumer Portable Devices

    Directory of Open Access Journals (Sweden)

    You Li

    2015-06-01

    Full Text Available This paper presents a WiFi-aided magnetic matching (MM algorithm for indoor pedestrian navigation with consumer portable devices. This algorithm reduces both the mismatching rate (i.e., the rate of matching to an incorrect point that is more than 20 m away from the true value and computational load of MM by using WiFi positioning solutions to limit the MM search space. Walking tests with Samsung Galaxy S3 and S4 smartphones in two different indoor environments (i.e., Environment #1 with abundant WiFi APs and significant magnetic features, and Environment #2 with less WiFi and magnetic information were conducted to evaluate the proposed algorithm. It was found that WiFi fingerprinting accuracy is related to the signal distributions. MM provided results with small fluctuations but had a significant mismatch rate; when aided by WiFi, MM’s robustness was significantly improved. The outcome of this research indicates that WiFi and MM have complementary characteristics as the former is a point-by-point matching approach and the latter is based on profile-matching. Furthermore, performance improvement through integrating WiFi and MM depends on the environment (e.g., the signal distributions of magnetic intensity and WiFi RSS: In Environment #1 tests, WiFi-aided MM and WiFi provided similar results; in Environment #2 tests, the former was approximately 41.6% better. Our results supported that the WiFi-aided MM algorithm provided more reliable solutions than both WiFi and MM in the areas that have poor WiFi signal distribution or indistinctive magnetic-gradient features.

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

    Science.gov (United States)

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

    1997-08-01

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

  17. Genetic Immunity to AIDS

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In an article on genetic immunity to AIDS published in Science magazine, American and Chinese scientists claim to have discovered why certain HIV carriers do not develop full-blown AIDS. They say that the key to this conundrum lies in a particular protein in the endocrine system that inhibits development of HIV.

  18. Neural Network Aided Adaptive UKF Algorithm for GPS/INS Integration Navigation

    Directory of Open Access Journals (Sweden)

    TAN Xinglong

    2015-04-01

    Full Text Available The predicted residual vectors should be zero-mean Gaussian white noise, which is the precondition for multiple fading factors adaptive filtering algorithm based on statistical information in GPS/INS integration system. However the abnormalities in observations will affect the distribution of the residual vectors. In this paper, a neural network aided adaptive unscented Kalman filter (UKF algorithm with multiple fading factors based on singular value decomposition(SVD is proposed. The algorithm uses the neural network algorithm to weaken the influence of the observed abnormalities on the residual vectors. Singular value decomposition instead of unscented transformation is adopted to suppress negative definite variation in priori covariance matrix of UKF. Since single fading factor in poor tracking of multiple variables has the limitation, multiple fading factors to adjust the predicted-state covariance matrix are constructed with better robustness so that each filter channel has different adjustability. Finally, vehicle measurement data are collected to validate the proposed algorithm. It shows that the neural network algorithm can prevent the observed abnormalities from affecting the distribution of the residual vectors, expanding the applied range of the adaptive algorithm. The neural network algorithm aided SVD-UKF algorithm with multiple fading factors is able to remove influences of state anomalies on condition of the observed abnormalities. The accuracy and reliability of the navigation solution can be improved by this algorithm.

  19. International Aid to Education

    Science.gov (United States)

    Benavot, Aaron

    2010-01-01

    Recent evidence highlights several worrisome trends regarding aid pledges and disbursements, which have been exacerbated by the global financial crisis. First, while overall development assistance rose in 2008, after 2 years of decline, the share of all sector aid going to the education sector has remained virtually unchanged at about 12 percent…

  20. Using landmarks to support older people in navigation

    OpenAIRE

    Goodman, J.; Gray, P.D.G.; Khammampad, K.; Brewster, S.

    2004-01-01

    Although landmarks are an integral aspect of navigation, they have rarely been used within electronic navigation aids. This paper describes the design of a pedestrian navigation aid for a handheld computer, which guides the user along a route using photographs of landmarks, together with audio and text instructions that reference these landmarks. This aid was designed with older users in mind who often find their mobility hampered by declines in sensory, cognitive and motor abilities. It was ...

  1. Vision-Aided Inertial Navigation Using Virtual Features

    OpenAIRE

    Martinelli, Agostino; Troiani, Chiara

    2012-01-01

    In this paper we consider an aerial vehicle equipped with a monocular camera and inertial sensors. Additionally, a laser pointer is mounted on the vehicle and it produces a laser spot. The laser spot is observed by the monocular camera and it is the unique point feature used in the proposed approach. We focus our attention to the case when the vehicle moves in proximity of a planar surface and in particular when the laser spot belongs to this surface. The paper provides two main contributions...

  2. Kalmtool used for laser scanner aided navigation in orchard

    DEFF Research Database (Denmark)

    Mogensen, Lars Valdemar; Hansen, Søren; Andersen, Jens Christian;

    2009-01-01

    This paper concerns localisation of an autonomous tractor in an orchard environment, with the purpose of designing a localisation solution to be compared with GPS. The localisation is based on an estimate found by an extended Kalman filter, which fuses measurements from encoders and gyro with row...

  3. Navigation Aids, COE gps all NA points, Published in 2009, 1:600 (1in=50ft) scale, Forsyth County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Navigation Aids dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Other information as of 2009. It is described as 'COE gps all NA...

  4. Vision-Aided Context-Aware Framework for Personal Navigation Services

    Science.gov (United States)

    Saeedi, S.; Moussa, A.; El-Sheimy, N., , Dr.

    2012-07-01

    The ubiquity of mobile devices (such as smartphones and tablet-PCs) has encouraged the use of location-based services (LBS) that are relevant to the current location and context of a mobile user. The main challenge of LBS is to find a pervasive and accurate personal navigation system (PNS) in different situations of a mobile user. In this paper, we propose a method of personal navigation for pedestrians that allows a user to freely move in outdoor environments. This system aims at detection of the context information which is useful for improving personal navigation. The context information for a PNS consists of user activity modes (e.g. walking, stationary, driving, and etc.) and the mobile device orientation and placement with respect to the user. After detecting the context information, a low-cost integrated positioning algorithm has been employed to estimate pedestrian navigation parameters. The method is based on the integration of the relative user's motion (changes of velocity and heading angle) estimation based on the video image matching and absolute position information provided by GPS. A Kalman filter (KF) has been used to improve the navigation solution when the user is walking and the phone is in his/her hand. The Experimental results demonstrate the capabilities of this method for outdoor personal navigation systems.

  5. Towards WSN-aided Navigation for Vehicles in Smart Cities: An Application Case Study.

    OpenAIRE

    Dagher, Roudy; Mitton, Nathalie; Amadou, Ibrahim

    2014-01-01

    With the emergence of Smart City concept, Wireless Sensor Networks (WSNs) become one of the key technologies for instrumenting the city, and thus providing its inhabitants with various services meant to improve their daily life. One of the identified applications is Smart Street Lightning, where the lamps are in a mesh network for remote control and maintenance purposes. This paper proposes Ubiquitous Navigation System (UNS), a WSN-based navigation system, which takes benefit from the Smart S...

  6. Comparison between audio and tactile systems for delivering simple navigational information to visually impaired pedestrians

    OpenAIRE

    Gustafson-Pearce, O; Billett, EH; Cecelja, F

    2007-01-01

    Many of the current GPS (Global Positioning Systems) navigation aids use an audio method to deliver navigation information to the user. For the visually impaired person this method can be problematic. The visually impaired pedestrian relies heavily on information contained within the ambient sound environment; for location and orientation information, navigation information, and importantly, safety information. In this paper we present the design of an innovative tactile interface and verific...

  7. Applying AHP to Web Navigation Design

    OpenAIRE

    Su-Hua Wang; Che-Hung Lin

    2008-01-01

    Due to increasing popularity of the World Wide Web, web-based systems are widely used. Most corporate web sites try to enhance their usability by providing artistic web presentations. However, the design of web sites is not judged solely on an artistic basis. Two of the most important design criteria for web sites are access to web content and navigation architecture. This research proposes a platform for automatically evaluating the quality of web navigation architecture. Because of the hier...

  8. Learning to aid learning.

    Science.gov (United States)

    Richards, Jacqui

    2016-01-01

    The National Health Service (NHS) is one of the largest employers in the world and, with 1.3 million staff, the biggest employer in Europe. With over three hundred different careers on offer (NHS 2015), the acquisition of skills and qualifications, through academic and clinical training, is an integral part of day-to-day life in the health service. As such, mentoring has become a significant feature in the preparation of healthcare professionals, to support students and ensure learning needs and experiences are appropriate to competency. This article examines the mentor's role, in relation to a teaching innovation designed to address students' identified learning needs to meet the requirements of the multi-professional learning and assessment in practice course NM6156. The effectiveness of the aids to learning will be assessed through an online quiz, and its usefulness will be analysed with reference to educational theories of learning and development. PMID:26975128

  9. Intelligent navigation to improve obstetrical sonography.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    2010-07-01

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

  11. From translation to navigation of different discourses

    DEFF Research Database (Denmark)

    Livonen, Mirja; Sonnenwald, Diane H.

    1998-01-01

    We propose a model of the search term selection process based on our empirical study of professional searchers during the pre-online stage of the search process. The model characterizes the selection of search terms as the navigation of different discourses. Discourse refers to the ways of talking...... and thinking about a certain topic; there often exists multiple, diverse discourses on the same topic. When selecting search terms, searchers appear to navigate a variety of discourses, i.e., they view the topic of a client's search request from the perspective of multiple discourse communities, and...... the searchers' own search experience. Data further suggest that searchers navigate these discourses dynamically and have preferences for certain discourses. Conceptualizing the selection of search terms as a meeting place of different discourses provides new insights into the complex nature of the...

  12. 33 CFR 245.20 - Determination of hazard to navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Determination of hazard to..., DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.20 Determination of hazard to navigation... Coast Guard district to jointly determine whether the obstruction poses a hazard to navigation....

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

    Science.gov (United States)

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

    2011-01-01

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

  14. Sensor fusion methods for indoor navigation using UWB radio aided INS/DR

    OpenAIRE

    Borràs Sillero, José

    2012-01-01

    [ANGLÈS] Some applications such as industrial automation, cargo handling, warehouse managing, monitoring of autonomous robot or personnel localization, require reliable indoor positioning. In particular, the requirement is to accurately localize a mobile wireless node in real-time. In outdoor scenarios, Global Navigation Satellite Systems (GNSSs) are commonly used for positioning. Nevertheless, they present notable shortcomings for being used in indoor applications. The principal disadvantage...

  15. AIDS Overspill to Everyman

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Xu Wenqing, national project officer of the UN International Children's Emergency Fund (UNICEF), recently issued a warning that the men/women ratio of HIV infection in China now stands at 5:5. This indicates that AiDS now threatens other than intravenous drug users, sex workers and hemophiliacs.

  16. Speech Recognition Technology Applied to Intelligent Mobile Navigation System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The capability of human-computer interaction reflects the intelligent degree of mobile navigation system.The navigation data and functions of mobile navigation system are divided into system commands and non-system commands in this paper.And then a group of speech commands are Abstracted.This paper applies speech recognition technology to intelligent mobile navigation system to process speech commands and does some deep research on the integration of speech recognition technology with mobile navigation system.The navigation operation can be performed by speech commands,which makes human-computer interaction easy during navigation.Speech command interface of navigation system is implemented by Dutty ++ Software,which is based on speech recognition system -Via Voice of IBM.Through navigation experiments,navigation can be done almost without keyboard,which proved that human-computer interaction is very convenient by speech commands and the reliability is also higher.

  17. Henan Surveys Blood Donors to Aid AIDS Prevention

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Central China's Henan Province, one of the worst AIDS-hit provinces in the country, launched a sweeping survey in September of past blood donors to ascertain tile number of HIV-infected individuals to aid AIDS prevention and control work.

  18. Particle-Filter-Based WiFi-Aided Reduced Inertial Sensors Navigation System for Indoor and GPS-Denied Environments

    OpenAIRE

    M. M. Atia; Korenberg, M. J.; A. Noureldin

    2012-01-01

    Indoor navigation is challenging due to unavailability of satellites-based signals indoors. Inertial Navigation Systems (INSs) may be used as standalone navigation indoors. However, INS suffers from growing drifts without bounds due to error accumulation. On the other side, the IEEE 802.11 WLAN (WiFi) is widely adopted which prompted many researchers to use it to provide positioning indoors using fingerprinting. However, due to WiFi signal noise and multipath errors indoors, WiFi positioning ...

  19. Fusion of Redundant Aided-inertial Sensors with Decentralised Kalman Filter for Autonomous Underwater Vehicle Navigation

    Directory of Open Access Journals (Sweden)

    Vaibhav Awale

    2015-11-01

    Full Text Available Most submarines carry more than one set of inertial navigation system (INS for redundancy and reliability. Apart from INS systems, the submarine carries other sensors that provide different navigation information. A major challenge is to combine these sensors and INS estimates in an optimal and robust manner for navigation. This issue has been addressed by Farrell1. The same approach is used in this paper to combine different sensor measurements along with INS system. However, since more than one INS system is available onboard, it would be better to use multiple INS systems at the same time to obtain a better estimate of states and to provide autonomy in the event of failure of one INS system. This would require us to combine the estimates obtained from local filters (one set of INS system integrated with external sensors, in some optimal way to provide a global estimate. Individual sensor and IMU measurements cannot be accessed in this scenario. Also, autonomous operation requires no sharing of information among local filters. Hence a decentralised Kalman filter approach is considered for combining the estimates of local filters to give a global estimate. This estimate would not be optimal, however. A better optimal estimate can be obtained by accessing individual measurements and augmenting the state vector in Kalman filter, but in that case, corruption of one INS system will lead to failure of the whole filter. Hence to ensure satisfactory performance of the filter even in the event of failure of some INS system, a decentralised Kalman filtering approach is considered.

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

    Science.gov (United States)

    Heatwole, Scott; Lanzi, Raymond J.

    2010-01-01

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

  1. HIV / AIDS: An Unequal Burden

    Science.gov (United States)

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

  2. Pigeon navigation : different routes lead to Frankfurt

    OpenAIRE

    Schiffner, Ingo; Wiltschko, Roswitha

    2014-01-01

    Background: Tracks of pigeons homing to the Frankfurt loft revealed an odd phenomenon: whereas birds returning from the North approach their loft more or less directly in a broad front, pigeons returning from the South choose, from 25 km from home onward, either of two corridors, a direct one and one with a considerable detour to the West. This implies differences in the navigational process. Methodology/Principle Findings: Pigeons released at sites at the beginning of the westerly corrido...

  3. AIDS

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000594.htm HIV/AIDS To use the sharing features on this page, ... immunodeficiency virus (HIV) is the virus that causes AIDS. When a person becomes infected with HIV, the ...

  4. Augmented Reality as a Navigation Tool to Employment Opportunities for Postsecondary Education Students with Intellectual Disabilities and Autism

    Science.gov (United States)

    McMahon, Don; Cihak, David F.; Wright, Rachel

    2015-01-01

    The purpose of this study was to examine the effects of location-based augmented reality navigation compared to Google Maps and paper maps as navigation aids for students with disabilities. The participants in this single subject study were three college students with intellectual disability and one college student with autism spectrum disorder.…

  5. Understanding physicians' response to AIDS.

    OpenAIRE

    Taylor, K M; Shapiro, M.; Skinner, H A; Eakin, J; Kelner, M

    1989-01-01

    Attempts to comprehend physicians' extreme reaction to AIDS (acquired immune deficiency syndrome) have met with great difficulty since the disease brings into question traditional norms and assumptions. As the medical profession struggles to develop guidelines and policies to help it deal with this disease, it can draw on very little systematic research on the effect of AIDS on physicians' attitudes and practices. We suggest a framework developed from the literature on physicians' and society...

  6. XVII International AIDS Conference: From Evidence to Action - AIDS 2008 and the global response to AIDS

    OpenAIRE

    Kort, Rodney

    2009-01-01

    The impact of the XVII International AIDS Conference (AIDS 2008) was reflected in a number of commitments from political and business leaders, who announced initiatives ranging from implementing comprehensive sexual education for young people in Latin America to reducing regulatory barriers and the price of drugs in the host country. The unprecedented media coverage brought attention and public awareness to the epidemic in Latin America. Several meetings and sessions at AIDS 2008 also address...

  7. Olfaction Contributes to Pelagic Navigation in a Coastal Shark

    OpenAIRE

    Nosal, Andrew P.; Chao, Yi; Farrara, John D.; Chai, Fei; Hastings, Philip A.

    2016-01-01

    How animals navigate the constantly moving and visually uniform pelagic realm, often along straight paths between distant sites, is an enduring mystery. The mechanisms enabling pelagic navigation in cartilaginous fishes are particularly understudied. We used shoreward navigation by leopard sharks (Triakis semifasciata) as a model system to test whether olfaction contributes to pelagic navigation. Leopard sharks were captured alongshore, transported 9 km offshore, released, and acoustically tr...

  8. 33 CFR 64.31 - Determination of hazard to navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Determination of hazard to... Provisions § 64.31 Determination of hazard to navigation. In determining whether an obstruction is a hazard... vessel incidents involving the obstruction; and (k) Whether the obstruction is defined as a hazard...

  9. Environmental gamma dose rate monitoring along Mumbai-Pune route using environmental radiation monitor with navigational aid

    International Nuclear Information System (INIS)

    A continuous environmental radiation monitor with navigational aid (ERMNA) for mapping natural gamma radiation background on country wide scale by deployment in railway coaches, has been designed. The system makes use of Indian railway network which is one of the widest network of railways in the world covering nearly complete length and breadth of the country. The system uses an energy compensated (within ± 30%) GN detectors for measurement of environmental dose rate due to natural background, a global positioning system (GPS) for on-line acquisition of positional co-ordinates (longitude and latitude) and an 8085 based data acquisition and processing unit. This system is deployed in guard's cabin of a train. The dose rate data tagged with positional co-ordinates and collected by the system during train journey is down loaded into a Lap Top PC for storage, analysis and graphical representation. The system has been used for background monitoring between Mumbai and Pune. The dose rates recorded over a period of three months ranging from November 1996 to February 1997 along the route show no change in the values which vary from 4 μr/h to 6 μR/h along the route. It drops down to <3 μR/h within tunnels en route. (author)

  10. How to perform first aid.

    Science.gov (United States)

    Gloster, Annabella Satu; Johnson, Phillip John

    2016-01-13

    RATIONALE AND KEY POINTS: This article aims to help nurses to perform first aid in a safe, effective and patient-centred manner. First aid comprises a series of simple, potentially life-saving steps that an individual can perform with minimal equipment. Although it is not a legal requirement to respond to an emergency situation outside of work, nurses have a professional duty to respond and provide care within the limits of their competency. First aid is the provision of immediate medical assistance to an ill or injured person until definitive medical treatment can be accessed. First aid can save lives and it is essential that nurses understand the basic principles. REFLECTIVE ACTIVITY: Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. Your skill in performing first aid and any areas where you may need to extend your knowledge. 2. How reading this article will change your practice. Subscribers can upload their reflective accounts at: rcni.com/portfolio . PMID:26758166

  11. Basal ganglia contributions to adaptive navigation.

    Science.gov (United States)

    Mizumori, Sheri J Y; Puryear, Corey B; Martig, Adria K

    2009-04-12

    The striatum has long been considered to be selectively important for nondeclarative, procedural types of memory. This stands in contrast with spatial context processing that is typically attributed to hippocampus. Neurophysiological evidence from studies of the neural mechanisms of adaptive navigation reveals that distinct neural systems such as the striatum and hippocampus continuously process task relevant information regardless of the current cognitive strategy. For example, both striatal and hippocampal neural representations reflect spatial location, directional heading, reward, and egocentric movement features of a test situation in an experience-dependent way, and independent of task demands. Thus, continual parallel processing across memory systems may be the norm rather than the exception. It is suggested that neuromodulators, such as dopamine, may serve to differentially regulate learning-induced neural plasticity mechanisms within these memory systems such that the most successful form of neural processing exerts the strongest control over response selection functions. In this way, dopamine may serve to optimize behavioral choices in the face of changing environmental demands during navigation. PMID:19056429

  12. Programs To Aid FORTRAN Programming

    Science.gov (United States)

    Ragosta, Arthur E.

    1987-01-01

    Program-development time decreased while program quality increased. FORTRAN Programming Tools are series of programming tools used to support development and maintenance of FORTRAN 77 source codes. Included are debugging aid, central-processing-unit time-monitoring program, source-code maintenance aids, print utilities, and library of useful, well-documented programs. Tools assist in reducing development time and encouraging high-quality programming. Although intended primarily for FORTRAN programmers, some tools used on data files and other programming languages. Written in FORTRAN 77.

  13. The return to foreign aid

    DEFF Research Database (Denmark)

    Dalgaard, Carl-Johan Lars; Hansen, Henrik

    We investigate the marginal productivity of investment across countries. The aim is to estimate the return on investments financed by foreign aid and by domestic resource mobilization, using aggregate data. Both returns are expected to vary across countries and time. Consequently we develop a...

  14. Reactions to Aid.

    Science.gov (United States)

    Neufeldt, David E.; French, Mark W.

    In this study, the effects of differing levels of obligation attached to a gift and differing levels of resources possessed by the donor on the attraction of the recipient toward the donor were studied. Using groups of between three and five college volunteers, subjects were seated in booths constructed so that they could not see each other, were…

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

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV / AIDS: Symptoms , Diagnosis, Prevention and Treatment Past Issues / Summer ... and have resulted in a dramatic decrease in AIDS deaths in the U.S. NIH Research to Results ...

  16. Adaptive Covariance Estimation Method for LiDAR-Aided Multi-Sensor Integrated Navigation Systems

    OpenAIRE

    Shifei Liu; Mohamed Maher Atia; Yanbin Gao; Aboelmagd Noureldin

    2015-01-01

    The accurate estimation of measurements covariance is a fundamental problem in sensors fusion algorithms and is crucial for the proper operation of filtering algorithms. This paper provides an innovative solution for this problem and realizes the proposed solution on a 2D indoor navigation system for unmanned ground vehicles (UGVs) that fuses measurements from a MEMS-grade gyroscope, speed measurements and a light detection and ranging (LiDAR) sensor. A computationally efficient weighted line...

  17. An aided navigation post processing filter for detailed seabed mapping UUVs

    OpenAIRE

    Kenneth Gade; Bjørn Jalving

    1999-01-01

    HUGIN is an untethered underwater vehicle (UUV) intended for bathymetric data collection for detailed seabed surveying. The HUGIN sensor suite, consisting of standard commercially available navigation sensors and a multibeam echosounder, is briefly presented. A Kalman filter based post processing integration of UUV sensors and survey vessel sensors is discussed. Resulting UUV position and heading accuracy and important characteristics of the post processing filter is shown with simulation res...

  18. Sensor-based navigation applied to intelligent electric vehicles

    OpenAIRE

    Alves De Lima, Danilo

    2015-01-01

    Autonomous navigation of car-like robots is a large domain with several techniques and applications working in cooperation. It ranges from low-level control to global navigation, passing by environment perception, robot localization, and many others in asensor-based approach. Although there are very advanced works, they still presenting problems and limitations related to the environment where the car is inserted and the sensors used. This work addresses the navigation problem of car-like rob...

  19. 33 CFR 209.180 - Temporary closure of waterway to navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Temporary closure of waterway to navigation. 209.180 Section 209.180 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE... navigation. (a) When an application is received for the temporary closure of a waterway for the...

  20. HIV / AIDS: An Unequal Burden

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV / AIDS: An Unequal Burden Past Issues / Summer 2009 ... high-risk category, emphasizes Dr. Cargill. Photo: iStock HIV and Pregnancy Are there ways to help HIV- ...

  1. Navigation errors encountered using weather-mapping radar for helicopter IFR guidance to oil rigs

    Science.gov (United States)

    Phillips, J. D.; Bull, J. S.; Hegarty, D. M.; Dugan, D. C.

    1980-01-01

    In 1978 a joint NASA-FAA helicopter flight test was conducted to examine the use of weather-mapping radar for IFR guidance during landing approaches to oil rig helipads. The following navigation errors were measured: total system error, radar-range error, radar-bearing error, and flight technical error. Three problem areas were identified: (1) operational problems leading to pilot blunders, (2) poor navigation to the downwind final approach point, and (3) pure homing on final approach. Analysis of these problem areas suggests improvement in the radar equipment, approach procedure, and pilot training, and gives valuable insight into the development of future navigation aids to serve the off-shore oil industry.

  2. A Qualitative Approach to Mobile Robot Navigation Using RFID

    International Nuclear Information System (INIS)

    Radio Frequency Identification (RFID) system allows automatic identification of items with RFID tags using radio-waves. As the RFID tag has its unique identification number, it is also possible to detect a specific region where the RFID tag lies in. Recently it is widely been used in mobile robot navigation, localization, and mapping both in indoor and outdoor environment. This paper represents a navigation strategy for autonomous mobile robot using passive RFID system. Conventional approaches, such as landmark or dead-reckoning with excessive number of sensors, have complexities in establishing the navigation and localization process. The proposed method satisfies less complexity in navigation strategy as well as estimation of not only the position but also the orientation of the autonomous robot. In this research, polar coordinate system is adopted on the navigation surface where RFID tags are places in a grid with constant displacements. This paper also presents the performance comparisons among various grid architectures through simulation to establish a better solution of the navigation system. In addition, some stationary obstacles are introduced in the navigation environment to satisfy the viability of the navigation process of the autonomous mobile robot

  3. Embedded Glove’ To Aid The Visually Impaired

    Directory of Open Access Journals (Sweden)

    Sankar Kumar S, Abarna J, Lavanya G, Nithya Lakshmi S

    2013-03-01

    Full Text Available This paper presents a model of ‘Embedded Glove’, a hand mounted tactile (vibration mechanism feedback Sound Navigation And Ranging (SONAR obstacle avoidance system, by warning through vibration motors for visually impaired to whom traveling in indoor/outdoor environments is really a difficult task. This system acts as an Electronic Travelling Aid (ETA providing independent mobility of the visually impaired. This model comprises of a glove strapped to the wrist, embedded with ultrasonic sensors, battery, microcontroller and vibrator motors. Along with being completely reliable, this system also provides to be a cost-effective guidance mechanism for the visually impaired. The system is designed to scan a wide area with a set of ultrasonic sensors which also provides a good range and speed in the detection of the obstacle. The detected obstacle is immediately notified to the possessor thereby the presence of obstacle along with its direction is conveyed to the visually impaired person by means of a tactile system. The energy consumption for the whole system is controlled by a Photovoltaic (PV panel, making it more efficient. The analysis described in this paper helps to estimate the distance at which the obstacle is present based on the reliability of measurement performed with ultrasonic sensors. It is also possible to detect the speed of moving objects in addition to direction with increased accuracy, with the enhanced response timings and varying intensities in the vibration mechanism.

  4. Navigator Approach to Improve Quality of Care for Vulnerable Populations in Mexico.

    Science.gov (United States)

    Ramos, Rebeca; Ferreira-Pinto, João; Loza, Oralia

    2015-01-01

    For nearly 30 years, Programa Compañeros Inc (Compañeros) has worked in Ciudad Juarez, Chihuahua, Mexico, to ensure that vulnerable populations can exercise their rights to receive HIV and substance abuse prevention and treatment services. Compañeros staff has worked to ameliorate the negative results that limit access to care to the most vulnerable individuals: those who are poor, homeless, sex workers, addicted, and others whose life context put them at greater risk for being infected with HIV. With support from the MAC AIDS Foundation, Compañeros has expanded its capacity to deliver services to persons living with HIV/AIDS (PLWHA) and to HIV-vulnerable populations. This short communication describes findings from an internal evaluation conducted to investigate the effectiveness of the MAC AIDS-funded navigator-based program implemented at Compañeros. PMID:26242198

  5. The Programmer's Guide to iSeries Navigator

    CERN Document Server

    Touhy, Paul

    2012-01-01

    iSeries Navigator is a favorite tool of operators and administrators-who use it with great success-but many programmers have missed the great programming tools that is provides! This book introduces you to iSeries Navigator along with all the powerful tools and interfaces that will expand your programming horizons. As iSeries applications continue to move toward a graphical user interface (GUI), so does the development environment. Programs such as CODE and WDSC may fill the need for the programming environment, but iSeries Navigator fills the programmer's need for general system access as wel

  6. Based on the Geomagnetic-aided Inertial Navigation System of State Feedback%基于地磁辅助惯性导航的状态反馈系统研究

    Institute of Scientific and Technical Information of China (English)

    唐志勇; 艾文娟; 刘岩

    2015-01-01

    According to the characteristics of low precision of the inertial sensor of MEMS technology,a high precision of integrated navigation algorithm is put forward, adopt geomagnetic aided navigation with closed-loop correction, and the deviation of the magnetic and heading Angle of the observation is in order to achieve high precision of inertial navi-gation and a higher dynamic performance .Experiments show that state feedback of inertial navigation system can over-come the error accumulation of inertial navigation,greatly improve the anti-interference ability of the geomagnetic navi-gation,get better navigation accuracy.%针对MEMS技术的惯性传感器低精度的特点,提出一种高精度的组合导航算法,采用地磁辅助导航进行闭环校正,并对地磁的自差和航向角进行观测,以达到较高的惯性导航精度和更高的动态性能.实验证明,状态反馈的惯性导航系统能很好地克服惯导的误差累积,大幅度提高了地磁导航的抗干扰能力,得到较好的导航精度.

  7. True navigation in birds: from quantum physics to global migration

    OpenAIRE

    Holland, R.A.

    2014-01-01

    Birds are capable of true navigation, the ability to return to a known goal from a place they have never visited before. This is demonstrated most spectacularly during the vast migratory journeys made by these animals year after year, often between continents and occasionally global in nature. However, it remains one of the great unanswered questions in science, despite more than 50 years of research in this field. Nevertheless, the study of true navigation in birds has made significant advan...

  8. Olfaction Contributes to Pelagic Navigation in a Coastal Shark.

    Science.gov (United States)

    Nosal, Andrew P; Chao, Yi; Farrara, John D; Chai, Fei; Hastings, Philip A

    2016-01-01

    How animals navigate the constantly moving and visually uniform pelagic realm, often along straight paths between distant sites, is an enduring mystery. The mechanisms enabling pelagic navigation in cartilaginous fishes are particularly understudied. We used shoreward navigation by leopard sharks (Triakis semifasciata) as a model system to test whether olfaction contributes to pelagic navigation. Leopard sharks were captured alongshore, transported 9 km offshore, released, and acoustically tracked for approximately 4 h each until the transmitter released. Eleven sharks were rendered anosmic (nares occluded with cotton wool soaked in petroleum jelly); fifteen were sham controls. Mean swimming depth was 28.7 m. On average, tracks of control sharks ended 62.6% closer to shore, following relatively straight paths that were significantly directed over spatial scales exceeding 1600 m. In contrast, tracks of anosmic sharks ended 37.2% closer to shore, following significantly more tortuous paths that approximated correlated random walks. These results held after swimming paths were adjusted for current drift. This is the first study to demonstrate experimentally that olfaction contributes to pelagic navigation in sharks, likely mediated by chemical gradients as has been hypothesized for birds. Given the similarities between the fluid three-dimensional chemical atmosphere and ocean, further research comparing swimming and flying animals may lead to a unifying paradigm explaining their extraordinary navigational abilities. PMID:26735492

  9. An indoor navigation system to support the visually impaired.

    Science.gov (United States)

    Riehle, T H; Lichter, P; Giudice, N A

    2008-01-01

    Indoor navigation technology is needed to support seamless mobility for the visually impaired. A small portable personal navigation device that provides current position, useful contextual wayfinding information about the indoor environment and directions to a destination would greatly improve access and independence for people with low vision. This paper describes the construction of such a device which utilizes a commercial Ultra-Wideband (UWB) asset tracking system to support real-time location and navigation information. Human trials were conducted to assess the efficacy of the system by comparing target-finding performance between blindfolded subjects using the navigation system for real-time guidance, and blindfolded subjects who only received speech information about their local surrounds but no route guidance information (similar to that available from a long cane or guide dog). A normal vision control condition was also run. The time and distance traveled was measured in each trial and a point-back test was performed after goal completion to assess cognitive map development. Statistically significant differences were observed between the three conditions in time and distance traveled; with the navigation system and the visual condition yielding the best results, and the navigation system dramatically outperforming the non-guided condition. PMID:19163698

  10. The developmental effectiveness of aid to Africa

    OpenAIRE

    Killick, Tony

    1991-01-01

    The principal aim of this paper is to examine the developmental effectiveness of aid to Sub-saharan Africa (SSA). The author uses an informal analytical framework to accomplish this. The framework provides a production-type equation for determining income growth and conveys that : 1) there are many influences besides aid on country economic performance; 2) domestic policies have a pervasive influence on the whole system; and 3) aid has an important influence in raising import and investment c...

  11. Aid to Africa: an unfinished agenda

    OpenAIRE

    Tony Addison; George Mavrotas; Mark McGillivray

    2005-01-01

    The Millennium Development Goals (MDGs) give aid to Africa a new emphasis. Yet aid flows to Africa have trended downward over the last decade, and as a consequence more Africans now live in poverty. This is especially true of Sub-Saharan Africa. Any progress towards the main MDG target of halving the number of people living in poverty clearly requires more aid. It also requires a better understanding of what drives aid volumes to Africa and precisely how these flows impact on African economie...

  12. An Interactive Aid to Registration

    Science.gov (United States)

    Gersting, John M., Jr.

    1975-01-01

    A brief nontechnical description of time-sharing computer software developed at Indiana University-Purdue University at Indianapolis as an aid in disseminating class schedule information. Design criteria include maintenance of a data base on sections offered, display of sections closed, and creation of reports on in individual schedules for closed…

  13. STOL terminal area operating systems (aircraft and onboard avionics, ATC, navigation aids)

    Science.gov (United States)

    Burrous, C.; Erzberger, H.; Johnson, N.; Neuman, F.

    1974-01-01

    Operational procedures and systems onboard the STOL aircraft which are required to enable the aircraft to perform acceptably in restricted airspace in all types of atmospheric conditions and weather are discussed. Results of simulation and flight investigations to establish operational criteria are presented.

  14. Minimally invasive transforaminal lumbar interbody fusion aided with computer-assisted spinal navigation system combined with electromyography monitoring

    Institute of Scientific and Technical Information of China (English)

    LUO Wei; ZHANG Fan; LIU Tie; DU Xing-li; CHEN An-ming; LI Feng

    2012-01-01

    Background Minimally invasive techniques are gaining wide-spread application in lumbar fusion surgery,because they may have advantage over conventional open surgery in approach-related morbidity.This research was aimed to evaluate the safety and accuracy of the techniques of minimally invasive transforaminal lumbar interbody fusion by using a computer-assisted spinal navigation system combined with electromyography monitoring.Methods Sixteen patients underwent minimally invasive transforaminal lumbar interbody fusion.A computer-assisted spinal navigation system and electromyography were used for guiding pedicle screw placement.The operative duration,blood loss,complications,and fluoroscopic time were recorded.Clinical outcome was assessed by Visual Analog Scale and Oswestry Disability Index.Radiographic images were obtained to evaluate the accuracy of pedicle screw placement and fusion rates.Results The Visual Analog Scale and Oswestry Disability Index scores were vastly improved postoperatively.A total of 64 pedicle screws were implanted and three were regarded as misplacement by post-operative CT scan.Three screw trajectories were adjusted according to intra-operative stimulus-evoked electromyography monitoring.The average fluoroscopy time in each patient was 31.8 seconds,which equals to 7.9 seconds per pedicle screw.No patients had instrument related neurological complications,infection,implant failure or revision.Successful fusion was found in all patients.Conclusions The combination of navigation system and real-time electromyography monitoring can make the minimally invasive operation more safe and accurate while decreasing radiation exposure time of the medical staff and patient and minimizing the chance and the degree of the pedicle screw misplacement.

  15. "Aid to Thought"--Just Simulate It!

    Science.gov (United States)

    Kinczkowski, Linda; Cardon, Phillip; Speelman, Pamela

    2015-01-01

    This paper provides examples of Aid-to-Thought uses in urban decision making, classroom laboratory planning, and in a ship antiaircraft defense system. Aid-to-Thought modeling and simulations are tools students can use effectively in a STEM classroom while meeting Standards for Technological Literacy Benchmarks O and R. These projects prepare…

  16. CONDUCTING IFR FLIGHTS WITHOUT THE USE OF CONVENTIONAL NAVIGATION AIDS AT THE UNCONTROLLED AERODROMES

    Directory of Open Access Journals (Sweden)

    Michał GERATOWSKI

    2016-03-01

    Full Text Available Flights conducted in accordance with the instrument flight rules (IFR allow to perform flights below the minimums for visual meteorological conditions. Nowadays, in Poland none of the uncontrolled aerodromes have implemented any IFR procedures. The paper presents an analysis of the international and national law in terms of establishing the appropriate IFR procedures at the uncontrolled aerodromes. The exemplary solutions, based on European uncontrolled aerodromes, are presented.

  17. Behavioral intervention to reduce AIDS risk activities.

    Science.gov (United States)

    Kelly, J A; St Lawrence, J S; Hood, H V; Brasfield, T L

    1989-02-01

    Behavior change can curtail the spread of acquired immune deficiency syndrome (AIDS). In this study, 104 gay men with a history of frequent AIDS high-risk behavior completed self-report, self-monitoring, and behavioral measures related to AIDS risk. The sample was randomly divided into experimental and waiting-list control groups. The experimental intervention provided AIDS risk education, cognitive-behavioral self-management training, sexual assertion training, and attention to the development of steady and self-affirming social supports. Experimental group participants greatly reduced their frequency of high-risk sexual practices and increased behavioral skills for refusing sexual coercions, AIDS risk knowledge, and adoption of "safer sex" practices. Change was maintained at the 8-month follow-up. PMID:2925974

  18. Three-Dimensional Gravity Model Applied to Underwater Navigation

    Institute of Scientific and Technical Information of China (English)

    YAN Lei; FENG Hao; DENG Zhongliang; GAO Zhengbing

    2004-01-01

    At present, new integrated navigation, which usesthe location function of reference gravity anomaly map to control the errors of the inertial navigation system (INS), has been developed in marine navigation. It is named the gravityaided INS. Both the INS and real-time computation of gravity anomalies need a 3-D marine normal gravity model.Conventionally, a reduction method applied in geophysical survey is directly introduced to observed data processing. This reduction does not separate anomaly from normal gravity in the observed data, so errors cannot be avoided. The 3-D marine normal gravity model was derived from the J2 gravity model, and is suitable for the region whose depth is less than 1000 m.

  19. Unfocused response to AIDS in Indonesia.

    Science.gov (United States)

    Maclaren, L

    1997-01-01

    Indonesia has a population of more than 200 million among which less than 500 official cases of HIV/AIDS have been recorded. The number of estimated cases is far greater. High rates of male migration, widespread prostitution, high rates of sexually transmitted disease infection, the absence of sex education for youth, women's low status, and the absence of a national AIDS awareness campaign were cited in 1993 as reasons why HIV would spread quickly throughout Indonesia. Access to basic information about AIDS remains a problem for both urban and rural populations in Indonesia. A national AIDS strategy was made public in 1993 by President Suharto. Supported by the Australians, the plan comprehensively covers almost every key aspect in managing HIV/AIDS. The plan since its release, however, has been largely ignored and the government has done little aside from a handful of television public service announcements, a few pamphlets distributed by the Department of Health, a few small HIV surveillance projects which have yielded little useful information, and the training of government officials to provide AIDS education. Approximately 15 nongovernmental organizations have been actively and successfully conducting AIDS prevention work. PMID:12320962

  20. Real-time Navigator Approach to Motion Problems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ This presentation attempts a summary discourse on the real time navigator approach to suppressing motion effects in thoracic MRA, particularly in coronary MRA. Organs in the thoracic body trunk experience physiologic motion due to cardiac contraction, respiration, peristalsis and other gross displacements.

  1. [Aged woman's vulnerability related to AIDS].

    Science.gov (United States)

    Silva, Carla Marins; Lopes, Fernanda Maria do Valle Martins; Vargens, Octavio Muniz da Costa

    2010-09-01

    This article is a systhematic literature review including the period from 1994 to 2009, whose objective was to discuss the aged woman's vulnerability in relation to Acquired Imunodeficiency Syndrome (Aids). The search for scientific texts was accomplished in the following databases: Biblioteca Virtual em Saúde, Scientific Eletronic Library Online (SciELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) and Medical Literature Analysis and Retrieval System Online (MEDLINE). The descriptors used were vulnerability, woman and Aids. Eighteen texts were analyzed, including articles in scientific journals, thesis and dissertations. As a conclusion, it was noted that aged women and vulnerability to Aids are directly related, through gender characteristics including submission and that were built historical and socially. We consider as fundamental the development of studies which may generate publications accessible to women, in order to help them see themselves as persons vulnerable to Aids contagion just for being women. PMID:21574329

  2. Ready To Navigate: Classroom GPS Applications.

    Science.gov (United States)

    Lucking, Robert A.; Christmann, Edwin P.

    2002-01-01

    Discusses the potential contribution of GPS and related Geographic Information Systems (GIS) technology to education. Provides resources for teachers to plan a lesson on exploring with the help of a GPS device in order to increase students' awareness of their surroundings and broaden understanding of their place in the world. (KHR)

  3. China Offers Humanitarian Aid to Mexico

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Chinese Foreign Ministry spokeswoman Jiang Yu announced the government’s decision to provide Mexico with humanitarian aid on April 29 in Beijing. The Chinese Government has offered $5 million in emergency humanitar

  4. Orion Navigation Sensitivities to Ground Station Infrastructure for Lunar Missions

    Science.gov (United States)

    Getchius, Joel; Kukitschek, Daniel; Crain, Timothy

    2008-01-01

    The Orion Crew Exploration Vehicle (CEV) will replace the Space Shuttle and serve as the next-generation spaceship to carry humans to the International Space Station and back to the Moon for the first time since the Apollo program. As in the Apollo and Space Shuttle programs, the Mission Control Navigation team will utilize radiometric measurements to determine the position and velocity of the CEV. In the case of lunar missions, the ground station infrastructure consisting of approximately twelve stations distributed about the Earth and known as the Apollo Manned Spaceflight Network, no longer exists. Therefore, additional tracking resources will have to be allocated or constructed to support mission operations for Orion lunar missions. This paper examines the sensitivity of Orion navigation for lunar missions to the number and distribution of tracking sites that form the ground station infrastructure.

  5. Behavioural adaptation to in-vehicle navigation systems

    OpenAIRE

    Forbes, Nicholas Lloyd

    2009-01-01

    This PhD investigates driver behavioural adaptation to in-vehicle navigation systems (IVNS). Behavioural adaptation is receiving an increasing amount of research attention in traffic psychology, but few studies have directly considered the concept in relation to IVNS. The thesis aims were addressed using a range of quantitative and qualitative methodologies. Using two online surveys, over 1300 drivers (including over 1000 IVNS users) were sampled, to identify a range of positive, neutral ...

  6. Navigational aspects of calling to the Great Harbour of Alexandria

    OpenAIRE

    Belov, Alexander

    2014-01-01

    More than ten years of archaeological surveys of the Great Harbour of Alexandria have completely changed the conception of the ancient topography of the port area of the city. The remains of ancient port structures show the high level of port's organization and well correspond to the descriptions of ancient authors. This new archaeological data permits to consider general aspects of navigation within the Great Harbour. The most probable courses of the ships calling to the Great Harbour and le...

  7. Fully self-contained vision-aided navigation and landing of a micro air vehicle independent from external sensor inputs

    Science.gov (United States)

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

    2012-06-01

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

  8. Using doppler radar images to estimate aircraft navigational heading error

    Science.gov (United States)

    Doerry, Armin W.; Jordan, Jay D.; Kim, Theodore J.

    2012-07-03

    A yaw angle error of a motion measurement system carried on an aircraft for navigation is estimated from Doppler radar images captured using the aircraft. At least two radar pulses aimed at respectively different physical locations in a targeted area are transmitted from a radar antenna carried on the aircraft. At least two Doppler radar images that respectively correspond to the at least two transmitted radar pulses are produced. These images are used to produce an estimate of the yaw angle error.

  9. A voxelization approach to navigate through nested geometries

    CERN Document Server

    Harrison, Brent Andrew

    2016-01-01

    High energy physics experiment software typically implements a detailed description of the geometry of the relevant detector. As modern detectors increase in complexity, modelling them becomes more challenging. Typically such models are built as a nested hierarchy of O(10000) volumes reaching a depth of 10 - 20. It is desirable to develop data structures and algorithms which allow fast and efficient navigation though a given detector geometry model. We investigate the feasibility of voxelisation techniques to this end.

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

    Science.gov (United States)

    Sanchez, Richard D.; Hudnut, Kenneth W.

    2004-01-01

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

  11. Image Based Solution to Occlusion Problem for Multiple Robots Navigation

    Directory of Open Access Journals (Sweden)

    Taj Mohammad Khan

    2012-04-01

    Full Text Available In machine vision, occlusions problem is always a challenging issue in image based mapping and navigation tasks. This paper presents a multiple view vision based algorithm for the development of occlusion-free map of the indoor environment. The map is assumed to be utilized by the mobile robots within the workspace. It has wide range of applications, including mobile robot path planning and navigation, access control in restricted areas, and surveillance systems. We used wall mounted fixed camera system. After intensity adjustment and background subtraction of the synchronously captured images, the image registration was performed. We applied our algorithm on the registered images to resolve the occlusion problem. This technique works well even in the existence of total occlusion for a longer period.

  12. Ecological validity of virtual environments to assess human navigation ability

    OpenAIRE

    van der Ham, Ineke J. M.; Faber, Annemarie M. E.; Venselaar, Matthijs; van Kreveld, Marc J.; Löffler, Maarten

    2015-01-01

    Route memory is frequently assessed in virtual environments. These environments can be presented in a fully controlled manner and are easy to use. Yet they lack the physical involvement that participants have when navigating real environments. For some aspects of route memory this may result in reduced performance in virtual environments. We assessed route memory performance in four different environments: real, virtual, virtual with directional information (compass), and hybrid. In the hybri...

  13. Neuro-fuzzy controller to navigate an unmanned vehicle

    OpenAIRE

    Selma, Boumediene; Chouraqui, Samira

    2013-01-01

    A Neuro-fuzzy control method for an Unmanned Vehicle (UV) simulation is described. The objective is guiding an autonomous vehicle to a desired destination along a desired path in an environment characterized by a terrain and a set of distinct objects, such as obstacles like donkey traffic lights and cars circulating in the trajectory. The autonomous navigate ability and road following precision are mainly influenced by its control strategy and real-time control performance. Fuzzy Logic Contro...

  14. Navigation between the planets. [Viking spacecraft flight to Mars

    Science.gov (United States)

    Melbourne, W. G.

    1976-01-01

    Recent advances in spacecraft tracking, chronometry, ephemerides, and orbit and trajectory determinations are reviewed. Improvements in timekeeping are reviewed, as well as precision distance and range measurements; orbit determinations, trajectory-correction maneuvers, flight path optimization, and information provided by rotation of the tracking station with the earth's surface. Doppler and tropospheric wave propagation effects are dealt with. Nongravitational perturbations (solar radiation pressure, release of gases from the spacecraft, stochastic unmodeled accelerations and sequential estimation to cope with them), the effect of the target planet's gravitational field upon close approach, and navigation problems in the outer reaches of the solar system (TV data telemetered back for inertial navigation) are covered. By-products of the research include: refined data on the mass of planets, on planetary mass distributions, planet configurations, on physical properties of the atmospheres and ionospheres of planets, and opportunities for refined tests of gravitation and relativity theories and models.

  15. Elections to the Mutual Aid Fund

    CERN Multimedia

    2016-01-01

    Every two years, according to Article 6 of the Regulations of the Mutual Aid Fund, the Committee of the Mutual Aid Fund must renew one third of its membership. This year three members are outgoing. Of these three, two will stand again and one will not.   Candidates should be ready to give approximately two hours a month during working time to the Fund whose aim is to assist colleagues in financial difficulties. We invite applications from CERN Staff who wish to stand for election as a member of the CERN Mutual Aid Fund to send in their application before 17 June 2016, by email to the Fund’s President, Connie Potter (connie.potter@cern.ch).

  16. Malaysia urges ASEAN to tackle AIDS crisis.

    Science.gov (United States)

    2000-08-01

    Urgent action is needed to fight the alarming spread of HIV/AIDS that infected 1.3 million people in Southeast Asia last year alone, Malaysia's foreign minister said July 24, 2000. Syed Hamid said the Association of Southeast Asian Nations (ASEAN) should tackle at regional and national level an epidemic that was taking its most drastic toll among the region's youth. "HIV/AIDS not only represents a major public health and social problem but is a serious challenge to development as well," Syed Hamid told the opening ceremony of ASEAN's 33rd annual foreign ministers' meeting. The crisis requires commitment at the "highest political level," he said, warning that HIV/AIDS could become a transnational problem within the 10-member group. Foreign ministers have recommended their leaders discuss the crisis later this year at an informal summit in Singapore and hold a summit on HIV/AIDS in conjunction with the 7th ASEAN Summit in Brunei next year. "I think people recognized the importance and the adverse impacts on our social development," Syed Hamid told reporters later. "I think it is a real issue that we cannot run away from." Among ASEAN members, Thailand, Cambodia, and Myanmar have some of the highest infection rates in Asia of HIV, the virus that causes AIDS. PMID:12349742

  17. HIV/AIDS Researchers Interaction with Schoolteachers: A Key to Combat AIDS among Brazilian Adolescents

    Science.gov (United States)

    Kashima, Simone; de Castro, Fabiola Attie; de Castro Amarante, Maria Fernanda; Barbieri, Marisa Ramos; Covas, Dimas Tadeu

    2008-01-01

    Considering the fact that information on HIV/AIDS is a strategy for disease control, this project was planned to provide comprehensive information about HIV infection and AIDS to schoolteachers and their students. Previous analysis of adolescent students' knowledge of HIV/AIDS showed that they still have doubts about transmission, diagnosis, and…

  18. Aid Effectiveness Revisited: Comparative Studies of Modalities of Aid to Asia and Africa

    OpenAIRE

    Hiroyuki Hino; Atsushi Iimi

    2008-01-01

    This paper provides a variety of evidence that shows that in Asia, aid leveraged private investment in the long run, while in Africa the correlation between aid and domestic investment was at best ambiguous. Aid in Africa was diametrically opposite to that of Asia in terms of the amounts the countries received, the sector compositions, the size of individual projects, and the intensity of donor involvement. The sharp contrast in aid effectiveness between Asia and Africa could be attributed at...

  19. Education to meet the challenge of AIDS.

    Science.gov (United States)

    Walton, R A; Rukeyser, J; Mastroianni, P; Doyle, S; Hunter, A; Mautner, B; Whitaker, P

    1989-01-01

    Studies of health care providers' attitudes have revealed that many have misconceptions and fears about AIDS and possess negative attitudes about caring for people with the disease. Merely transmitting the basic facts about AIDS is insufficient to prepare health care workers to deal with AIDS patients. This article discusses the need for continuing education for health care professionals and educators and offers a model for the development of educational programs. The model is being developed in the School of Allied Health Professions, State University of New York at Stony Brook. Principles of "andragogy"--involvement of both the learner and the educator in identifying students' needs, planning learning experiences, and ongoing evaluation of the learning process--are discussed. PMID:10294008

  20. OPEC Aid to the Developing Countries.

    Science.gov (United States)

    OECD Observer, 1978

    1978-01-01

    For the third consecutive year, OPEC aid amounted to more than $5.5 billion, representing more than two percent of the gross national product. This is compared to 0.31 percent for members of OECD's Development Assistance Committee. (Author/BB)

  1. Application of γ ray to field investigation of float mud in ocean outfalls and navigation channels

    International Nuclear Information System (INIS)

    The γ ray gauge is used to investigate the density and distribution of float mud in navigation channel area on site. The results provide important prototype information for effectively using navigable depth and studying rules of back silting. (authors)

  2. Nuclear power to aid development

    International Nuclear Information System (INIS)

    Before nuclear power can play its full role in contributing to the development of less advanced countries, full understanding of the capital investment, fuel costs and other economic factors as well as of the place it must take in existing power programmes is essential. Some insight into the problems and prospects was gained at the symposium arranged by the Agency, and held in Istanbul in October, on 'Nuclear Energy Costs and Economic Development'. (author)

  3. Impacts to HIV/AIDS of gender

    Directory of Open Access Journals (Sweden)

    Emel Taşçı

    2007-03-01

    Full Text Available The impact of gender on HIV/AIDS is an important dimension in understanding the evolution of the epidemic. HIV/AIDS is one of the vital problems of our century. HIV/AIDS is not merely a medical disease but also is a problem, which possesses economical, cultural, psychological and social dimensions. Women are more vulnerable to HIV than men because of biological and cultural factors. Besides women who carry HIV virus experience difficulty in taking care of their own health, they also carry the burden of possibility that their children and other members of the family might catch HIV virus. Most often, social support is insufficient and the conditions brought by treatment cannot be utilized appropriately due to external interventions. Most of the problems that women under the risk of HIV run into are largely social rather than medical. Many women infected with HIV were isolated because they didn’t get of sufficient social support or didn’t equal time for their care and it is thought that this inequality still continues. An analysis of the impact of gender on HIV/AIDS demonstrates the importance of integrating gender into HIV programming and finding ways to strengthen women by implementing policies and programs that increase their access to education and information. Women's empowerment is vital to reversing the epidemic.

  4. Colleges Offer Extra Aid to Strapped Students

    Science.gov (United States)

    Supiano, Beckie

    2009-01-01

    Among all the uncertainty colleges face in this recession, they are sure of one thing: Families are feeling less than confident about their ability to pay for higher education. In response, colleges are creating more student-aid programs or expanding existing ones. Others are offering students additional counseling or a grace period for paying…

  5. 40 CFR 227.10 - Hazards to fishing, navigation, shorelines or beaches.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Hazards to fishing, navigation... Environmental Impact § 227.10 Hazards to fishing, navigation, shorelines or beaches. (a) Wastes which may present a serious obstacle to fishing or navigation may be dumped only at disposal sites and...

  6. Should Animals Navigating Over Short Distances Switch to a Magnetic Compass Sense?

    OpenAIRE

    Russell Wyeth

    2010-01-01

    Magnetoreception can play a substantial role in long distance navigation by animals. I hypothesize that locomotion guided by a magnetic compass sense could also play a role in short distance navigation. Animals identify mates, prey or other short distance navigational goals using different sensory modalities (olfaction, vision, audition, etc.) to detect sensory cues associated with those goals. In conditions where these cues become unreliable for navigation (due to flow changes, obstructio...

  7. An Introduction to Search Engines and Web Navigation

    CERN Document Server

    Levene, Mark

    2010-01-01

    This book is a second edition, updated and expanded to explain the technologies that help us find information on the web.  Search engines and web navigation tools have become ubiquitous in our day to day use of the web as an information source, a tool for commercial transactions and a social computing tool. Moreover, through the mobile web we have access to the web's services when we are on the move.  This book demystifies the tools that we use when interacting with the web, and gives the reader a detailed overview of where we are and where we are going in terms of search engine

  8. The political economy of aid flows to North Africa

    OpenAIRE

    Harrigan, Jane

    2011-01-01

    This paper provides an historical overview of aid flows to North Africa. It assesses the aid allocation process and argues that past aid flows to the region have been heavily influenced by donor political interests. This has reduced the effectiveness of aid which, with the exception of Tunisia, has not been associated with sustained economic growth. The Arab Spring provides an opportunity to reappraise aid flows to North Africa and it is argued that future flows need to support the democratiz...

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

    Science.gov (United States)

    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. PMID:26040931

  10. Flight route planning for geomagnetic aided navigation using a singularity exponent%基于奇异指数的地磁辅助导航路径规划算法

    Institute of Scientific and Technical Information of China (English)

    李欣; 王德生; 孙立国; 李世丹

    2011-01-01

    针对地磁场测量信息观测性较差的现状,为了获得较高的辅助导航定位精度和良好的滤波性能,进行了地磁辅助导航路径规划研究.以反映地磁场变化幅度的奇异指数做为地磁场信息量的度量,以点迹总信息量及信息量递增性构建辅助导航路径性能指标.采用粒子滤波算法,对不同路径进行了辅助导航性能仿真对比.仿真结果表明,该算法规划的辅助导航路径比其他路径具有更好的导航定位精度和滤波性能.%Geomagnetic navigation precisely obtains positions from geomagnetic field information. In order to obtain precise positions and filter stability, the poor observability of measured geomagnetic data was analyzed, the singularity exponent was used to measure the amount of geomagnetic information, the performance index was built using gross information and increasing factors, and flight route planning for geomagnetic aided navigation was researched using a singularity exponent. Finally, performance was compared using the flight simulation along different routes with a particle filter as the geomagnetic filter algorithm. The simulation results show that aided navigation routing planned using this algorithm has better positioning accuracy, filtering stability, and convergence.

  11. Are there Negative Returns to Aid? a Comment

    OpenAIRE

    Mwanza Nkusu

    2004-01-01

    Amid controversies surrounding aid effectiveness, an increasing number of empirical studies find support for the idea that aid can spur growth and that the aid-growth relationship is nonlinear. Lensink and White propose a model to illustrate the possible existence of what has been labeled an "aid Laffer curve." This short paper highlights the model's weaknesses and suggests that the model does not fulfill the purpose of illustrating the possible existence of negative returns to aid.

  12. A robust method to detect zero velocity for improved 3D personal navigation using inertial sensors.

    Science.gov (United States)

    Xu, Zhengyi; Wei, Jianming; Zhang, Bo; Yang, Weijun

    2015-01-01

    This paper proposes a robust zero velocity (ZV) detector algorithm to accurately calculate stationary periods in a gait cycle. The proposed algorithm adopts an effective gait cycle segmentation method and introduces a Bayesian network (BN) model based on the measurements of inertial sensors and kinesiology knowledge to infer the ZV period. During the detected ZV period, an Extended Kalman Filter (EKF) is used to estimate the error states and calibrate the position error. The experiments reveal that the removal rate of ZV false detections by the proposed method increases 80% compared with traditional method at high walking speed. Furthermore, based on the detected ZV, the Personal Inertial Navigation System (PINS) algorithm aided by EKF performs better, especially in the altitude aspect. PMID:25831086

  13. To reiterate the concept of self-aid and buddy-aid for combat wounded

    Directory of Open Access Journals (Sweden)

    Zhong-jie HE

    2015-11-01

    Full Text Available Explore new concept of self-aid and buddy-aid for combat wounded based on the emergency timeliness and the challenges we are going to face in the future combats, the importance of self-aid, buddy-aid and rescue are discussed. The concept and characteristics of self-aid and buddy-aid in our army are reviewed, and the care of the wounded in foreign armies were reviewed. Based on the experiences gained from previous combats, and the results of "Medical Service Mission-2014 Drill", it was believed that the emergency rescue of battle wounded should follow the timeliness rule and the principle of self-aid and buddy-aid technology. It might be beneficial to use cell protective agent, urgent relief of life-threatening conditions such as profuse bleeding from extremities, suffocation, pneumothorax, and traumatic shock etc., in order to stabilize the general condition of the wounded, according to the regime of "Platinum 10 minutes" and "golden 1 hour", self-aid and buddy-aid might play an important role in preventing early death and late morbidity of the wounded, thus helps reduce the mortality rate or the victims of combat wounds. DOI: 10.11855/j.issn.0577-7402.2015.11.01

  14. Neuro-fuzzy controller to navigate an unmanned vehicle.

    Science.gov (United States)

    Selma, Boumediene; Chouraqui, Samira

    2013-12-01

    A Neuro-fuzzy control method for an Unmanned Vehicle (UV) simulation is described. The objective is guiding an autonomous vehicle to a desired destination along a desired path in an environment characterized by a terrain and a set of distinct objects, such as obstacles like donkey traffic lights and cars circulating in the trajectory. The autonomous navigate ability and road following precision are mainly influenced by its control strategy and real-time control performance. Fuzzy Logic Controller can very well describe the desired system behavior with simple "if-then" relations owing the designer to derive "if-then" rules manually by trial and error. On the other hand, Neural Networks perform function approximation of a system but cannot interpret the solution obtained neither check if its solution is plausible. The two approaches are complementary. Combining them, Neural Networks will allow learning capability while Fuzzy-Logic will bring knowledge representation (Neuro-Fuzzy). In this paper, an artificial neural network fuzzy inference system (ANFIS) controller is described and implemented to navigate the autonomous vehicle. Results show several improvements in the control system adjusted by neuro-fuzzy techniques in comparison to the previous methods like Artificial Neural Network (ANN). PMID:23705105

  15. Sensitivity analysis of helicopter IMC decelerating steep approach and landing performance to navigation system parameters

    Science.gov (United States)

    Karmali, M. S.; Phatak, A. V.

    1982-01-01

    Results of a study to investigate, by means of a computer simulation, the performance sensitivity of helicopter IMC DSAL operations as a function of navigation system parameters are presented. A mathematical model representing generically a navigation system is formulated. The scenario simulated consists of a straight in helicopter approach to landing along a 6 deg glideslope. The deceleration magnitude chosen is 03g. The navigation model parameters are varied and the statistics of the total system errors (TSE) computed. These statistics are used to determine the critical navigation system parameters that affect the performance of the closed-loop navigation, guidance and control system of a UH-1H helicopter.

  16. Developing Navigation Competencies to Care for Older Rural Adults with Advanced Illness.

    Science.gov (United States)

    Duggleby, Wendy; Robinson, Carole A; Kaasalainen, Sharon; Pesut, Barbara; Nekolaichuk, Cheryl; MacLeod, Roderick; Keating, Norah C; Santos Salas, Anna; Hallstrom, Lars K; Fraser, Kimberly D; Williams, Allison; Struthers-Montford, Kelly; Swindle, Jennifer

    2016-06-01

    Navigators help rural older adults with advanced illness and their families connect to needed resources, information, and people to improve their quality of life. This article describes the process used to engage experts - in rural aging, rural palliative care, and navigation - as well as rural community stakeholders to develop a conceptual definition of navigation and delineate navigation competencies for the care of this population. A discussion paper on the important considerations for navigation in this population was developed followed by a four-phased Delphi process with 30 expert panel members. Study results culminated in five general navigation competencies for health care providers caring for older rural persons and their families at end of life: provide patient/family screening; advocate for the patient/family; facilitate community connections; coordinate access to services and resources; and promote active engagement. Specific competencies were also developed. These competencies provide the foundation for research and curriculum development in navigation. PMID:27093177

  17. Cell Cycle Regulates Nuclear Stability of AID and Determines the Cellular Response to AID.

    Directory of Open Access Journals (Sweden)

    Quy Le

    2015-09-01

    Full Text Available AID (Activation Induced Deaminase deaminates cytosines in DNA to initiate immunoglobulin gene diversification and to reprogram CpG methylation in early development. AID is potentially highly mutagenic, and it causes genomic instability evident as translocations in B cell malignancies. Here we show that AID is cell cycle regulated. By high content screening microscopy, we demonstrate that AID undergoes nuclear degradation more slowly in G1 phase than in S or G2-M phase, and that mutations that affect regulatory phosphorylation or catalytic activity can alter AID stability and abundance. We directly test the role of cell cycle regulation by fusing AID to tags that destabilize nuclear protein outside of G1 or S-G2/M phases. We show that enforced nuclear localization of AID in G1 phase accelerates somatic hypermutation and class switch recombination, and is well-tolerated; while nuclear AID compromises viability in S-G2/M phase cells. We identify AID derivatives that accelerate somatic hypermutation with minimal impact on viability, which will be useful tools for engineering genes and proteins by iterative mutagenesis and selection. Our results further suggest that use of cell cycle tags to regulate nuclear stability may be generally applicable to studying DNA repair and to engineering the genome.

  18. Radar and electronic navigation

    CERN Document Server

    Sonnenberg, G J

    2013-01-01

    Radar and Electronic Navigation, Sixth Edition discusses radar in marine navigation, underwater navigational aids, direction finding, the Decca navigator system, and the Omega system. The book also describes the Loran system for position fixing, the navy navigation satellite system, and the global positioning system (GPS). It reviews the principles, operation, presentations, specifications, and uses of radar. It also describes GPS, a real time position-fixing system in three dimensions (longitude, latitude, altitude), plus velocity information with Universal Time Coordinated (UTC). It is accur

  19. Indoor Subspacing to Implement Indoorgml for Indoor Navigation

    Science.gov (United States)

    Jung, H.; Lee, J.

    2015-10-01

    According to an increasing demand for indoor navigation, there are great attempts to develop applicable indoor network. Representation for a room as a node is not sufficient to apply complex and large buildings. As OGC established IndoorGML, subspacing to partition the space for constructing logical network is introduced. Concerning subspacing for indoor network, transition space like halls or corridors also have to be considered. This study presents the subspacing process for creating an indoor network in shopping mall. Furthermore, categorization of transition space is performed and subspacing of this space is considered. Hall and squares in mall is especially defined for subspacing. Finally, implementation of subspacing process for indoor network is presented.

  20. INDOOR SUBSPACING TO IMPLEMENT INDOORGML FOR INDOOR NAVIGATION

    Directory of Open Access Journals (Sweden)

    H. Jung

    2015-10-01

    Full Text Available According to an increasing demand for indoor navigation, there are great attempts to develop applicable indoor network. Representation for a room as a node is not sufficient to apply complex and large buildings. As OGC established IndoorGML, subspacing to partition the space for constructing logical network is introduced. Concerning subspacing for indoor network, transition space like halls or corridors also have to be considered. This study presents the subspacing process for creating an indoor network in shopping mall. Furthermore, categorization of transition space is performed and subspacing of this space is considered. Hall and squares in mall is especially defined for subspacing. Finally, implementation of subspacing process for indoor network is presented.

  1. DEVELOPMENT OF TECHNOLOGY TO REMOTELY NAVIGATE VERTICAL PIPE ARRAYS

    Energy Technology Data Exchange (ETDEWEB)

    Krementz, D.; Immel, D.; Vrettos, N.; Nance, T.; Marzolf, A.

    2011-07-01

    Situations exist around the Savannah River Site (SRS) and the Department of Energy (DOE) complex where it is advantageous to remotely navigate vertical pipe arrays. Specific examples are waste tanks in the SRS Tank Farms, which contain horizontal cooling coils at the tank bottom, vertical cooling coils throughout and a limited number of access points or ''risers''. These factors limit accessibility to many parts of these tanks by conventional means. Pipe Traveler technology has been developed to address these issues. The Pipe Traveler addresses these issues by using the vertical cooling coils as its medium of travel. The unit operates by grabbing a pipe using dual grippers located on either side of the equipment. Once securely attached to the pipe a drive wheel is extended to come in contact with the pipe. Rotation of the drive wheel causes the unit to rotate around the pipe. This action is continued until the second set of grippers is aligned with the next pipe. Extension pistons are actuated to extend the second set of grippers in contact with a second pipe. The second set of grippers is then actuated to grasp the pipe. The first set of grippers releases the original pipe and the process is repeated until the unit reaches its desired location. Once at the tool deployment location the desired tool may be used. The current design has proven the concept of pipe-to-pipe navigation. Testing of the Pipe Traveler has proven its ability to transfer itself from one pipe to another.

  2. Freshman Year Financial Aid Nudges: An Experiment to Increase Financial Aid Renewal and Sophomore Year Persistence

    Science.gov (United States)

    Castleman, Benjamin L.; Page, Lindsay C.

    2013-01-01

    While considerable effort has been invested to increase FAFSA completion among high school seniors, there has been much less investment to ensure that college freshmen re-apply for financial aid. Text messaging is a promising approach to inform students of important stages in the financial aid re-application process and to connect them to…

  3. Physicians Mutual Aid Group: A Response to AIDS-Related Burnout.

    Science.gov (United States)

    Garside, Bruce

    1993-01-01

    Describes origins and functioning of physician's mutual aid group for physicians providing primary care to people with Acquired Immune Deficiency Syndrome (AIDS). Offers suggestions related to overcoming resistance physicians might have to participating in such a group and reviews modalities that were helpful in facilitating participants' ability…

  4. HIV, AIDS, and the Future

    Science.gov (United States)

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

  5. "Aid Like a Paycheck: Engaging with Policymakers and Practitioners to Evaluate and Improve Financial Aid"

    Science.gov (United States)

    Weissman, Evan; O'Connell, Jesse

    2016-01-01

    "Aid Like A Paycheck" is a large-scale pilot evaluation of whether an innovative approach to disbursing financial aid can improve academic and financial outcomes for low-income community college students. Lessons from the pilot evaluation were used to create and fine-tune a logic model depicting activities, outputs, mediators, and…

  6. Impact of Patient Navigation from Diagnosis to Treatment in an Urban Safety Net Breast Cancer Population

    Directory of Open Access Journals (Sweden)

    Nisreen A Haideri, Jill A Moormeier

    2011-01-01

    Full Text Available Background: Disparities between U.S. population groups in cancer incidence, treatment and outcome have been well documented. Literature evidence is scarce regarding the impact of patient navigator programs on elimination of these differences.Methods: This is a retrospective case series analysis .The pre -navigation group included patients diagnosed between January 1, 1997 and December 31, 1999. The post -navigation group included patients diagnosed between January 1, 2000 and December 31, 2003. Cancer stage, time from presentation to treatment and treatment outcome were compared by review of medical records.Results: Three hundred and thirty five women were diagnosed between January 1, 1997 and December 31, 2003. Thirteen patients were ineligible, 103 women in the pre- navigation group, and 219 women in the post-navigation group. 157 (72% received navigation services. The median time to first treatment was decreased by 9 days (42 days in pre -navigation group compared to 33 days in post -navigator group. Race, insurance and clinical presentation did not influence the time to treatment.Conclusions: Navigation program did not influence the stage of presentation or the overall survival of women. There was a modest decrease in the time between initial presentation and definitive therapy. The utility of navigator programs is likely to vary with each institution.

  7. NAVIGATOR (FER)

    International Nuclear Information System (INIS)

    The NAVIGATOR concept is based on the negative-ion-grounded 500 keV/20 MW neutral beam injection system (NBI system), which has been proposed and studied at JAERI. The NAVIGATOR concept contains two categories; one is the NAVIGATOR machine as a tokamak reactor, and the other is the NAVIGATOR philosphy as a quiding principle in fusion research. The NAVIGATOR concept should be applied in a phased approach to and beyond the operating goal for the FER (Fusion Experimental Reactor, the next generation tokamak machine in Japan). The mission of the FER is to realize self-ignition and a long controlled burn of about 800 seconds and to develop and test fusion technologies, including the tritiumfuel cycle, superconducting magnet, remote maintenance and breeding blanket test modules. The NAVIGATOR concept is composed of three major elements, that is, reliable operation scenarios, reliable maintenability and suffiecient flexibility of the reactor. The NAVIGATOR concept well supports the ideas of phased operation and phased construction of the FER, which will result in the reduction technological risk. (author). 4 refs.; 3 figs

  8. A job performance aid to criticality safety

    International Nuclear Information System (INIS)

    The handling of hazardous materials is becoming more and more of a major concern to everyone. As a result the laws and restrictions regulating the handling, storage, disposal, etc., of these materials are increasing in complexity. These restrictions must be presented directly to the people that actually handle the material and the manner in which this is done will affect the reliability and efficiency of the process. The use of human factors design principles and extensive user input in the design of these job performance aids will greatly contribute to the understandability and usability of the end product-safe handling of hazardous materials

  9. Whimsical Path to Math: Implementing the Navigations Series

    Science.gov (United States)

    Christy, Donna M.

    2006-01-01

    This article describes lessons that link mathematics topics with literature, the NCTM's Navigations series, and art projects. Each lesson is designed around a theme and is laced throughout with fantasy. (Contains 13 figures.)

  10. Online Trajectory Reshaping for a Launch Vehicle to Minimize the Final Error Caused by Navigation and Guidance

    Directory of Open Access Journals (Sweden)

    Tessy Thomas

    2013-05-01

    Full Text Available Autonomous launch vehicles, once lifted off from the launch pad, equipped with an onboard intelligence which aids in achieving the mission objectives with high accuracy. The accuracy of the mission depends basically on navigation and guidance errors caused at burnout condition, after which the vehicle follows an elliptical path upto impact. The paper describes how to handle the final impact and injection error caused by these navigation and guidance errors. In the current work the initial burnout conditions are tuned and corrected such that the terminal impact point is achieved within the desired tolerance bounds. A two point boundary value problem is solved using the gradient method, for determining the impact errors. The algorithm is validated by simulation studies for various burnout conditions.

  11. Easy rider: monkeys learn to drive a wheelchair to navigate through a complex maze.

    Directory of Open Access Journals (Sweden)

    Stephanie Etienne

    Full Text Available The neurological bases of spatial navigation are mainly investigated in rodents and seldom in primates. The few studies led on spatial navigation in both human and non-human primates are performed in virtual, not in real environments. This is mostly because of methodological difficulties inherent in conducting research on freely-moving monkeys in real world environments. There is some incertitude, however, regarding the extrapolation of rodent spatial navigation strategies to primates. Here we present an entirely new platform for investigating real spatial navigation in rhesus monkeys. We showed that monkeys can learn a pathway by using different strategies. In these experiments three monkeys learned to drive the wheelchair and to follow a specified route through a real maze. After learning the route, probe tests revealed that animals successively use three distinct navigation strategies based on i the place of the reward, ii the direction taken to obtain reward or iii a cue indicating reward location. The strategy used depended of the options proposed and the duration of learning. This study reveals that monkeys, like rodents and humans, switch between different spatial navigation strategies with extended practice, implying well-conserved brain learning systems across different species. This new task with freely driving monkeys provides a good support for the electrophysiological and pharmacological investigation of spatial navigation in the real world by making possible electrophysiological and pharmacological investigations.

  12. Targeting of AID-mediated sequence diversification to immunoglobulin genes

    OpenAIRE

    Kothapalli, Naga Rama; Fugmann, Sebastian D.

    2011-01-01

    Activation-induced cytidine deaminase (AID) is a key enzyme for antibody-mediated immune responses. Antibodies are encoded by the immunoglobulin genes and AID acts as a transcription-dependent DNA mutator on these genes to improve antibody affinity and effector functions. An emerging theme in field is that many transcribed genes are potential targets of AID, presenting an obvious danger to genomic integrity. Thus there are mechanisms in place to ensure that mutagenic outcomes of AID activity ...

  13. "America Responds to AIDS": its content, development process, and outcome.

    OpenAIRE

    Woods, D. R.; Davis, D; Westover, B J

    1991-01-01

    During the 1987-90 period, five phases of new AIDS information materials were released to the general public in the ARTA campaign, including a national mailer. The five were "General Awareness: Humanizing AIDS" in October 1987, "Understanding AIDS," the national mailout, April 1988, "Women at Risk/Multiple Partner, Sexually Active Adults," October 1988, "Parents and Youth," May 1989, and "Preventing HIV Infection and AIDS: Taking The Next Steps," July 1990. From planning to implementation to ...

  14. Increased condom use needed to fight AIDS.

    Science.gov (United States)

    Worldwide, at least 33 million people are infected with HIV, another 14 million have died, and approximately 16,000 people are newly infected each day, 60% of whom are women. An estimated 6-9 billion condoms are currently used throughout the world each year. However, a report from the Johns Hopkins University School of Hygiene and Public Health has determined that the level of condom use must be increased to 24 billion units annually in order to check the spread of HIV/AIDS and other sexually transmitted diseases. An estimated 71% of total condom need is among sexually active unmarried men, while the rest of the need is among married men who have extramarital affairs and by married couples. Condoms should be made accessible to all at subsidized prices and provided not only through health clinics and retail shops, but also in hotels, bars, grocery stores, and vending machines. New efforts are needed to make condoms more accessible, including lowering their cost, effectively promoting their use, and overcoming the many social and personal obstacles to their use, especially in developing countries where the impact of AIDS is the most severe. Special programs should target specific groups, including youth, unmarried men, and prostitutes, while condom promotion should also aim to improve the image of condoms by portraying them as fun, reliable, and important. Finally, political and religious leaders should speak out in favor of condom use, while the mass media should openly discuss condoms. PMID:12295207

  15. Asia needs political commitment to fight AIDS.

    Science.gov (United States)

    1997-06-01

    Delegates from China, Cambodia, Indonesia, Malaysia, Burma, Thailand, and Vietnam to a Joint UN Program on HIV/AIDS (UNAIDS) workshop in Bangkok urged their governments to give priority to the prevention of HIV and AIDS. There are already approximately 3 million people infected with HIV in Asia. Their numbers should increase by 1-2 million by the year 2000. However, devoid of any prevention measures, 2-5 million more people could instead become infected over the same period. Thailand, where many people have adopted condom use and the patronage of brothels and prostitutes has declined, was noted as a success story at the workshop in preventing the further spread of HIV. The level of risky sexual behavior in Thailand has declined to such an extent that HIV case projections made in 1991 for the year 2000 have been revised to a lower number. An estimated more than 100,000 people are infected with HIV in Indonesia, a country in which the epidemic may grow to 2.5 million cases by 2000 unless successful prevention programs are implemented. PMID:12347936

  16. Gray-Box model of inland navigation channel: application to the Cuinchy–Fontinettes reach

    OpenAIRE

    Horváth, Klaudia; Duviella, Eric; Blesa Izquierdo, Joaquim; Rajaoarisoa, Lala H.; Bolea Monte, Yolanda; Puig Cayuela, Vicenç; Chuquet, Karine

    2014-01-01

    In a context of global change, inland navigation transport has gained interest with economic and environmental benefits. The development of this means of conveyance requires the improvement of its management rules to deal with the increase of navigation (schedules and frequency) and the potential impact of global change. To achieve this aim, it is first necessary to have a better knowledge about the dynamics of inland navigation networks and their interaction with the environment. Second, the...

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

    Science.gov (United States)

    Shanklin, Teresa A.

    2012-01-01

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

  18. Access to Adequate Healthcare for Hmong Women: A Patient Navigation Program to Increase Pap Test Screening

    Directory of Open Access Journals (Sweden)

    Moon S. Chen, Jr

    2010-01-01

    Full Text Available This paper describes the development and implementation of a Hmong Cervical Cancer Intervention Program utilizing a patient navigation model to raise cervical cancer awareness for Hmong women through educational workshops and to assist Hmong women in obtaining a Pap test. Out of 402 women who participated in a baseline survey, the Patient Navigation Program was able to enroll 109 participants who had not had a Pap test in the past 3 years and had never had a Pap test. Through utilization of outreach, an awareness campaign and patient navigation support, at least 38 percent of 109 participants obtained a Pap test. Overall, 21 workshops and 43 outreach activities were conducted by the Hmong Women’s Heritage Association, leading to 63 percent of those enrolled in the Patient Navigation Program who could be contacted to obtain a Pap test.

  19. Navigating the fungal polyketide chemical space: from genes to molecules.

    Science.gov (United States)

    Chooi, Yit-Heng; Tang, Yi

    2012-11-16

    The iterative type I polyketide synthases (IPKSs) are central to the biosynthesis of an enormously diverse array of natural products in fungi. These natural products, known as polyketides, exhibit a wide range of biological activities and include clinically important drugs as well as undesirable toxins. The PKSs synthesize these structurally diverse polyketides via a series of decarboxylative condensations of malonyl-CoA extender units and β-keto modifications in a highly programmed manner. Significant progress has been made over the past few years in understanding the biosynthetic mechanism and programming of fungal PKSs. The continuously expanding fungal genome sequence data have sparked genome-directed discoveries of new fungal PKSs and associated products. The increasing number of fungal PKSs that have been linked to their products along with in-depth biochemical and structural characterizations of these large enzymes have remarkably improved our knowledge on the molecular basis for polyketide structural diversity in fungi. This Perspective highlights the recent advances and examines how the newly expanded paradigm has contributed to our ability to link fungal PKS genes to chemical structures and vice versa. The knowledge will help us navigate through the logarithmically expanding seas of genomic information for polyketide compound discovery and provided opportunities to reprogram these megasynthases to generate new chemical entities. PMID:22938194

  20. Indoor Navigation Using an iPhone

    OpenAIRE

    Emilsson, André

    2010-01-01

    Indoor navigation could be used in many applications to enhance performance in its specific area. Anything from serious life critical tasks like aiding firefighters or coordinating military attacks to more simple every day use like finding a desired shop in a large supermarket could be considered. Smartphones of today introduce an interesting platform with capabilities like existing, more clumsy, indoor navigation systems. The iPhone 3GS is a powerful smartphone that lets the programmer use i...

  1. Ecological validity of virtual environments to assess human navigation ability

    Directory of Open Access Journals (Sweden)

    Ineke eVan Der Ham

    2015-05-01

    Full Text Available Route memory is frequently assessed in virtual environments. These environments can be presented in a fully controlled manner and are easy to use. Yet they lack the physical involvement that participants have when navigating real environments. For some aspects of route memory this may result in reduced performance in virtual environments. We assessed route memory performance in four different environments: real, virtual, virtual with directional information (compass, and hybrid. In the hybrid environment, participants walked the route outside on an open field, while all route information (i.e. path, landmarks was shown simultaneously on a handheld tablet computer. Results indicate that performance in the real life environment was better than in the virtual conditions for tasks relying on survey knowledge, like pointing to start and end point, and map drawing. Performance in the hybrid condition however, hardly differed from real life performance. Performance in the virtual environment did not benefit from directional information. Given these findings, the hybrid condition may offer the best of both worlds: the performance level is comparable to that of real life for route memory, yet it offers full control of visual input during route learning.

  2. 33 CFR 207.170d - Taylor Creek, navigation lock (S-193) across the entrance to Taylor Creek at Lake Okeechobee...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Taylor Creek, navigation lock (S..., DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.170d Taylor Creek, navigation lock..., and navigation. (a) The owner of or agency controlling the lock shall not be required to operate...

  3. Acute stress switches spatial navigation strategy from egocentric to allocentric in a virtual Morris water maze.

    Science.gov (United States)

    van Gerven, Dustin J H; Ferguson, Thomas; Skelton, Ronald W

    2016-07-01

    Stress and stress hormones are known to influence the function of the hippocampus, a brain structure critical for cognitive-map-based, allocentric spatial navigation. The caudate nucleus, a brain structure critical for stimulus-response-based, egocentric navigation, is not as sensitive to stress. Evidence for this comes from rodent studies, which show that acute stress or stress hormones impair allocentric, but not egocentric navigation. However, there have been few studies investigating the effect of acute stress on human spatial navigation, and the results of these have been equivocal. To date, no study has investigated whether acute stress can shift human navigational strategy selection between allocentric and egocentric navigation. The present study investigated this question by exposing participants to an acute psychological stressor (the Paced Auditory Serial Addition Task, PASAT), before testing navigational strategy selection in the Dual-Strategy Maze, a modified virtual Morris water maze. In the Dual-Strategy maze, participants can chose to navigate using a constellation of extra-maze cues (allocentrically) or using a single cue proximal to the goal platform (egocentrically). Surprisingly, PASAT stress biased participants to solve the maze allocentrically significantly more, rather than less, often. These findings have implications for understanding the effects of acute stress on cognitive function in general, and the function of the hippocampus in particular. PMID:27174311

  4. From organized internal traffic to collective navigation of bacterial swarms

    International Nuclear Information System (INIS)

    Bacterial swarming resulting in collective navigation over surfaces provides a valuable example of cooperative colonization of new territories. The social bacterium Paenibacillus vortex exhibits successful and diverse swarming strategies. When grown on hard agar surfaces with peptone, P. vortex develops complex colonies of vortices (rotating bacterial aggregates). In contrast, during growth on Mueller–Hinton broth gelled into a soft agar surface, a new strategy of multi-level organization is revealed: the colonies are organized into a special network of swarms (or ‘snakes’ of a fraction of millimeter in width) with intricate internal traffic. More specifically, cell movement is organized in two or three lanes of bacteria traveling between the back and the front of the swarm. This special form of cellular logistics suggests new methods in which bacteria can share resources and risk while searching for food or migrating into new territories. While the vortices-based organization on hard agar surfaces has been modeled before, here, we introduce a new multi-agent bacterial swarming model devised to capture the swarms-based organization on soft surfaces. We test two putative generic mechanisms that may underlie the observed swarming logistics: (i) chemo-activated taxis in response to chemical cues and (ii) special align-and-push interactions between the bacteria and the boundary of the layer of lubricant collectively generated by the swarming bacteria. Using realistic parameters, the model captures the observed phenomena with semi-quantitative agreement in terms of the velocity as well as the dynamics of the swarm and its envelope. This agreement implies that the bacteria interactions with the swarm boundary play a crucial role in mediating the interplay between the collective movement of the swarm and the internal traffic dynamics. (paper)

  5. From organized internal traffic to collective navigation of bacterial swarms

    Science.gov (United States)

    Ariel, Gil; Shklarsh, Adi; Kalisman, Oren; Ingham, Colin; Ben-Jacob, Eshel

    2013-12-01

    Bacterial swarming resulting in collective navigation over surfaces provides a valuable example of cooperative colonization of new territories. The social bacterium Paenibacillus vortex exhibits successful and diverse swarming strategies. When grown on hard agar surfaces with peptone, P. vortex develops complex colonies of vortices (rotating bacterial aggregates). In contrast, during growth on Mueller-Hinton broth gelled into a soft agar surface, a new strategy of multi-level organization is revealed: the colonies are organized into a special network of swarms (or ‘snakes’ of a fraction of millimeter in width) with intricate internal traffic. More specifically, cell movement is organized in two or three lanes of bacteria traveling between the back and the front of the swarm. This special form of cellular logistics suggests new methods in which bacteria can share resources and risk while searching for food or migrating into new territories. While the vortices-based organization on hard agar surfaces has been modeled before, here, we introduce a new multi-agent bacterial swarming model devised to capture the swarms-based organization on soft surfaces. We test two putative generic mechanisms that may underlie the observed swarming logistics: (i) chemo-activated taxis in response to chemical cues and (ii) special align-and-push interactions between the bacteria and the boundary of the layer of lubricant collectively generated by the swarming bacteria. Using realistic parameters, the model captures the observed phenomena with semi-quantitative agreement in terms of the velocity as well as the dynamics of the swarm and its envelope. This agreement implies that the bacteria interactions with the swarm boundary play a crucial role in mediating the interplay between the collective movement of the swarm and the internal traffic dynamics.

  6. Assisting Older Persons With Adjusting to Hearing Aids.

    Science.gov (United States)

    Lane, Kari R; Clark, M Kathleen

    2016-02-01

    This intervention study tested the feasibility and initial effect of Hearing Aid Reintroduction (HEAR) to assist persons aged 70 to 85 years adjust to hearing aids. Following this 30-day intervention, hearing aid use increased between 1 and 8 hr per day with 50% of participants able to wear them for at least 4 hr. Hearing aid satisfaction improved from not satisfied to satisfied overall. The study demonstrated that HEAR is feasible and could improve hearing aid use of a substantial number of older persons who had previously failed to adjust to their hearing aids and had given up. However, further testing among a larger and more diverse population is needed to better understand the effectiveness and sustainability of the intervention. PMID:25520326

  7. Universal navigation on smartphones

    CERN Document Server

    Karimi, Hassan A

    2011-01-01

    Universal navigation is accessible primarily through smart phones providing users with navigation information regardless of the environment (i.e., outdoor or indoor). ""Universal Navigation for Smart Phones"" provide the most up-to-date navigation technologies and systems for both outdoor and indoor navigation. It also provides a comparison of the similarities and differences between outdoor and indoor navigation systems from both a technological stand point and user's perspective. All aspects of navigation systems including geo-positioning, wireless communication, databases, and functions wil

  8. Machine Vision for Relative Spacecraft Navigation During Approach to Docking

    Science.gov (United States)

    Chien, Chiun-Hong; Baker, Kenneth

    2011-01-01

    This paper describes a machine vision system for relative spacecraft navigation during the terminal phase of approach to docking that: 1) matches high contrast image features of the target vehicle, as seen by a camera that is bore-sighted to the docking adapter on the chase vehicle, to the corresponding features in a 3d model of the docking adapter on the target vehicle and 2) is robust to on-orbit lighting. An implementation is provided for the case of the Space Shuttle Orbiter docking to the International Space Station (ISS) with quantitative test results using a full scale, medium fidelity mock-up of the ISS docking adapter mounted on a 6-DOF motion platform at the NASA Marshall Spaceflight Center Flight Robotics Laboratory and qualitative test results using recorded video from the Orbiter Docking System Camera (ODSC) during multiple orbiter to ISS docking missions. The Natural Feature Image Registration (NFIR) system consists of two modules: 1) Tracking which tracks the target object from image to image and estimates the position and orientation (pose) of the docking camera relative to the target object and 2) Acquisition which recognizes the target object if it is in the docking camera Field-of-View and provides an approximate pose that is used to initialize tracking. Detected image edges are matched to the 3d model edges whose predicted location, based on the pose estimate and its first time derivative from the previous frame, is closest to the detected edge1 . Mismatches are eliminated using a rigid motion constraint. The remaining 2d image to 3d model matches are used to make a least squares estimate of the change in relative pose from the previous image to the current image. The changes in position and in attitude are used as data for two Kalman filters whose outputs are smoothed estimate of position and velocity plus attitude and attitude rate that are then used to predict the location of the 3d model features in the next image.

  9. Constraints to Achieving the MDGs with Scaled-Up Aid

    OpenAIRE

    François Bourguignon; Mark Sundberg

    2006-01-01

    This paper examines the macroeconomic and structural constraints to scaling up aid flows to developing countries to meet the Millennium Development Goals in 2015, including infrastructure, competitiveness and the real exchange rate, labour markets, fiscal constraints, governance, and aid volatility and fragmentation. The impact of these constraints on cost-efficient sequencing and composition of scaled-up aid flows is considered, using a dynamic computable general equilibrium model applied to...

  10. Artificial intelligence aid to efficient plant operations

    International Nuclear Information System (INIS)

    As the nuclear power industry matures, it is becoming more and more important that plants be operated in an efficient, cost-effective manner, without, of course, any decrease in the essential margins of safety. Indeed, most opportunities for improved efficiency have little or no relation to nuclear safety, but are based on trade-offs among operator controllable parameters both within and external to the reactor itself. While these trade-offs are describable in terms of basic physical theory, thermodynamics, and the mathematics of control systems, their actual application is highly plant specific and influenced even by the day-to-day condition of the various plant components. This paper proposes the use of artificial intelligence techniques to construct a computer-based expert assistant to the plant operator for the purpose of aiding him in improving the efficiency of plant operation on a routine basis. The proposed system, which only advises the human operator, seems more amenable to the current regulatory approach than a truly automated control system even if the latter provides for manual override

  11. Recent Trends in the Arctic Navigable Ice Season and Links to Atmospheric Circulation

    Science.gov (United States)

    Maslanik, J.; Drobot, S.

    2002-12-01

    One of the potential effects of Arctic climate warming is an increase in the navigable ice season, perhaps resulting in development of the Arctic as a major shipping route. The distance from western North American ports to Europe through the Northwest Passage (NWP) or the Northern Sea Route (NSR) is typically 20 to 60 percent shorter than travel through the Panama Canal, while travel between Europe and the Far East may be reduced by as much as three weeks compared to transport through the Suez Canal. An increase in the navigable ice season would also improve commercial opportunities within the Arctic region, such as mineral and oil exploration and tourism, which could potentially expand the economic base of Arctic residents and companies, but which would also have negative environmental impacts. Utilizing daily passive-microwave derived sea ice concentrations, trends and variability in the Arctic navigable ice season are examined from 1979 through 2001. Trend analyses suggest large increases in the length of the navigable ice season in the Kara and Barents seas, the Sea of Okhotsk, and the Beaufort Sea, with decreases in the length of the navigable ice season in the Bering Sea. Interannual variations in the navigable ice season largely are governed by fluctuations in low-frequency atmospheric circulation, although the specific annular modes affecting the length of the navigable ice season vary by region. In the Beaufort and East Siberian seas, variations in the North Atlantic Oscillation/Arctic Oscillation control the navigable ice season, while variations in the East Pacific anomaly play an important role in controlling the navigable ice season in the Kara and Barents seas. In Hudson Bay, the Canadian Arctic Archipelago, and Baffin Bay, interannual variations in the navigable ice season are strongly related to the Pacific Decadal Oscillation.

  12. Aid to fragile states: Do donors help or hinder?

    OpenAIRE

    Browne, Stephen

    2007-01-01

    he record of aid to fragile and poorly-performing states is the real test of aid effectiveness. Rich countries can justify aid to fragile states both through altruism and self-interest. But, with some exceptions, donors have appeared at the wrong times and with the wrong attitudes, even sometimes undermining development progress. State failure has dimensions of both will and capacity. Failure demands constructive engagement by donors, in some cases to save people in weak states from their lea...

  13. Klimanavigator - Climate Navigator - Gateway to climate knowledge in Germany

    Science.gov (United States)

    Schuck-Zöller, Susanne

    2013-04-01

    Objective More than 50 German research institutions and networks are represented on www.klimanavigator.de, a common platform, where information about their work, and the latest findings from climate research and adaptation can be found. Thus Klimanavigator as a gateway to climate knowledge provides a information portal for those who have to respond to climate change. The internet portal gives an overview of the present state of research and is estimated as a decision support tool for appropriate mitigation and adaptation measures. Target Groups The portal collects the German climate research institutions to publish their scientific knowledge in a non-scientific language. Economists, policymakers, administration and the media are bound to find the names of scientific experts and institutions by an elaborated research tool. Methodology The chapter "Dossiers" is edited by the Klimanavigator-Coordinator CSC. It gathers information to a special issue looked upon from various points of view. Publications of outstanding German scientists are presented side by side, current knowledge is being synthesized, scientifically reviewed and disseminated. The latest news from climate and adaptation research is presented in an own chapter, dedicated to the press releases of the portal members. Via RSS-feed the press releases are collected from the different partner institutions. Thirdly, portraits of the member institutions, that are individually edited by themselves, draw a map of science in Germany and help to find appropriate cooperation partners. For the future further development is being planned. Common Management Klimanavigator is being managed by the partners in common. The main decisions concerning the concept and shape of the portal are made by the partners' assembly. An elected editorial committee decides about the content between the assemblies. The Climate Service Center (part of the Helmholtz-Zentrum Geesthacht) concentrates on facilitating the cooperation, and

  14. Religious leaders' response to AIDS in Nigeria.

    Science.gov (United States)

    Ucheaga, D N; Hartwig, K A

    2010-01-01

    Increasingly, faith-based organisations are being asked to participate in HIV prevention and care activities. This paper presents formative research on HIV/AIDS prevention messages, activities and policies within six religious institutions in Cross River State, Nigeria, at urban and rural sites. Data collection methods included a review of written HIV policies gathered from national church and mosque offices and 48 key informant interviews. The study highlights differences in messages between mainstream and Pentecostal Christians and Muslims. Although all groups stated a core message of abstinence outside marriage and faithfulness within marriage, Pentecostal churches tended to have more messages of punishment and condemnation for people infected with HIV. Urban churches/mosques tended to have more HIV resources and programmes. Attitudes towards condom use varied by denomination and individual; although few saw a role for religious institutions to promote condoms there were exceptions voiced. These findings indicate that religious organisations are already playing a role in HIV prevention but their responses are not uniform. Public health organisations and policy-makers should be aware of these denominational differences as they engage with religious institutions and leaders in HIV prevention and care. PMID:20155545

  15. Creating social spaces to tackle AIDS-related stigma

    DEFF Research Database (Denmark)

    Campbell, C.; Skovdal, Morten; Gibbs, A.

    2011-01-01

    An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people living with AIDS and challenging or contributing to HIV/AIDS-related stigma. Treating church groups as social spaces in which HIV/AIDS-related stigma may potentially be...... challenged, we systematically review this literature, identifying five themes that highlight the complex and contradictory role of the church as a potential agent of health-enhancing social change. In many ways the church perpetuates HIV/AIDS-related stigma through (i) moralistic attitudes and (ii) its...... reinforcement of conservative gender ideologies. However some churches have managed move towards action that makes a more positive contribution to HIV/AIDS management through (iii) promoting various forms of social control for HIV prevention, (iv) contributing to the care and support of the AIDS-affected and (v...

  16. Monitoring the exposure of "America Responds to AIDS" PSA campaign.

    OpenAIRE

    Gentry, E M; Jorgensen, C M

    1991-01-01

    The "America Responds to AIDS" campaign is the focal point of an integrated mass communications system for AIDS education and information dissemination developed by the National AIDS Information and Education Program of the Centers for Disease Control. Television and radio public service announcements are an integral part of the campaign. One measure of their success is the extent to which they are aired on both national and local levels. Since 1987, the total dollar value for air time donate...

  17. Mathematical and statistical approaches to AIDS epidemiology

    CERN Document Server

    1989-01-01

    The 18 research articles of this volume discuss the major themes that have emerged from mathematical and statistical research in the epidemiology of HIV. The opening paper reviews important recent contributions. Five sections follow: Statistical Methodology and Forecasting, Infectivity and the HIV, Heterogeneity and HIV Transmission Dynamics, Social Dynamics and AIDS, and The Immune System and The HIV. In each, leading experts in AIDS epidemiology present the recent results. Some address the role of variable infectivity, heterogeneous mixing, and long periods of infectiousness in the dynamics of HIV; others concentrate on parameter estimation and short-term forecasting. The last section looks at the interaction between the HIV and the immune system.

  18. Computer-aided testing of pilot response to critical in-flight events

    Science.gov (United States)

    Giffin, W. C.; Rockwell, T. H.

    1984-01-01

    This research on pilot response to critical in-flight events employs a unique methodology including an interactive computer-aided scenario-testing system. Navigation displays, instrument-panel displays, and assorted textual material are presented on a touch-sensitive CRT screen. Problem diagnosis scenarios, destination-diversion scenarios and combined destination/diagnostic tests are available. A complete time history of all data inquiries and responses is maintained. Sample results of diagnosis scenarios obtained from testing 38 licensed pilots are presented and discussed.

  19. How Significant and Effective has Foreign Aid to Indonesia been?

    OpenAIRE

    Anis Chowdhury; Iman Sugema

    2005-01-01

    With the improvement of relationship with the western countries after the demise of the old order regime of President Soekarno, Indonesia received a large volume of foreign aid that played a crucial role in the recovery of the economy. Indonesia remained a significant recipient of foreign aid through out the 1970s and 1980s, especially during the balance of payments crises. In addition to smoothing out balance of payments problems and providing budgetary supports, aid played an important cata...

  20. Navigating the Financial Aid System in the Community College: The Lived Experience of Students Formerly in Foster Care

    Science.gov (United States)

    Solemsaas, Rachel

    2011-01-01

    For many low-income and disadvantaged students formerly in foster care, community colleges are the main post-secondary educational pathway to socioeconomic opportunities. However, students formerly in foster care face many barriers in accessing college as well as actually succeeding in achieving a college degree. Although considerable efforts have…

  1. Hearing aids' electromagnetic immunity to environmental RF fields

    International Nuclear Information System (INIS)

    In this work, the electromagnetic interference on hearing aids was evaluated. Electromagnetic (EM) immunity tests on different types of hearing aids were carried out, using signals of intensity and modulation comparable to those present in the environment. The purpose of this work is to characterise the interference, establishing the immunity threshold for different frequencies and finding out which types of hearing aids are more susceptible, and in which frequency range. The tests were carried out in a GTEM cell on seven hearing aids, using AM and GSM signals in the radiofrequency (RF) range. (authors)

  2. A Kalman Approach to Lunar Surface Navigation using Radiometric and Inertial Measurements

    Science.gov (United States)

    Chelmins, David T.; Welch, Bryan W.; Sands, O. Scott; Nguyen, Binh V.

    2009-01-01

    Future lunar missions supporting the NASA Vision for Space Exploration will rely on a surface navigation system to determine astronaut position, guide exploration, and return safely to the lunar habitat. In this report, we investigate one potential architecture for surface navigation, using an extended Kalman filter to integrate radiometric and inertial measurements. We present a possible infrastructure to support this technique, and we examine an approach to simulating navigational accuracy based on several different system configurations. The results show that position error can be reduced to 1 m after 5 min of processing, given two satellites, one surface communication terminal, and knowledge of the starting position to within 100 m.

  3. Inertial Sensor Self-Calibration in a Visually-Aided Navigation Approach for a Micro-AUV

    Science.gov (United States)

    Bonin-Font, Francisco; Massot-Campos, Miquel; Negre-Carrasco, Pep Lluis; Oliver-Codina, Gabriel; Beltran, Joan P.

    2015-01-01

    This paper presents a new solution for underwater observation, image recording, mapping and 3D reconstruction in shallow waters. The platform, designed as a research and testing tool, is based on a small underwater robot equipped with a MEMS-based IMU, two stereo cameras and a pressure sensor. The data given by the sensors are fused, adjusted and corrected in a multiplicative error state Kalman filter (MESKF), which returns a single vector with the pose and twist of the vehicle and the biases of the inertial sensors (the accelerometer and the gyroscope). The inclusion of these biases in the state vector permits their self-calibration and stabilization, improving the estimates of the robot orientation. Experiments in controlled underwater scenarios and in the sea have demonstrated a satisfactory performance and the capacity of the vehicle to operate in real environments and in real time. PMID:25602263

  4. Inertial Sensor Self-Calibration in a Visually-Aided Navigation Approach for a Micro-AUV

    Directory of Open Access Journals (Sweden)

    Francisco Bonin-Font

    2015-01-01

    Full Text Available This paper presents a new solution for underwater observation, image recording, mapping and 3D reconstruction in shallow waters. The platform, designed as a research and testing tool, is based on a small underwater robot equipped with a MEMS-based IMU, two stereo cameras and a pressure sensor. The data given by the sensors are fused, adjusted and corrected in a multiplicative error state Kalman filter (MESKF, which returns a single vector with the pose and twist of the vehicle and the biases of the inertial sensors (the accelerometer and the gyroscope. The inclusion of these biases in the state vector permits their self-calibration and stabilization, improving the estimates of the robot orientation. Experiments in controlled underwater scenarios and in the sea have demonstrated a satisfactory performance and the capacity of the vehicle to operate in real environments and in real time.

  5. Inertial sensor self-calibration in a visually-aided navigation approach for a micro-AUV.

    Science.gov (United States)

    Bonin-Font, Francisco; Massot-Campos, Miquel; Negre-Carrasco, Pep Lluis; Oliver-Codina, Gabriel; Beltran, Joan P

    2015-01-01

    This paper presents a new solution for underwater observation, image recording, mapping and 3D reconstruction in shallow waters. The platform, designed as a research and testing tool, is based on a small underwater robot equipped with a MEMS-based IMU, two stereo cameras and a pressure sensor. The data given by the sensors are fused, adjusted and corrected in a multiplicative error state Kalman filter (MESKF), which returns a single vector with the pose and twist of the vehicle and the biases of the inertial sensors (the accelerometer and the gyroscope). The inclusion of these biases in the state vector permits their self-calibration and stabilization, improving the estimates of the robot orientation. Experiments in controlled underwater scenarios and in the sea have demonstrated a satisfactory performance and the capacity of the vehicle to operate in real environments and in real time. PMID:25602263

  6. HIV, AIDS, and the Future

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues HIV / AIDS HIV, AIDS, and the Future Past Issues / Summer 2009 ... turn Javascript on. Photo: The NAMES Project Foundation HIV and AIDS are a global catastrophe. While advances ...

  7. Spatial navigation impairment is proportional to right hippocampal volume

    Czech Academy of Sciences Publication Activity Database

    Nedelská, Z.; Andel, R.; Laczó, J.; Vlček, Kamil; Hořínek, D.; Lisý, J.; Sheardová, K.; Bureš, Jan; Hort, J.

    2012-01-01

    Roč. 109, č. 7 (2012), s. 2590-2594. ISSN 0027-8424 R&D Projects: GA ČR(CZ) GA309/09/1053; GA ČR(CZ) GA309/09/0286; GA MŠk(CZ) 1M0517; GA MŠk(CZ) LC554 Grant ostatní: GA MZd(CZ) NS10331 Institutional research plan: CEZ:AV0Z50110509 Keywords : spatial navigation * Alzheimer’s Disease * hippocampal volume Subject RIV: FH - Neurology Impact factor: 9.737, year: 2012

  8. Principles of Celestial Navigation: An Online Resource for Introducing Practical Astronomy to the Public

    Science.gov (United States)

    Urban, Sean E.

    2015-08-01

    Astronomy is often called a "gateway" science because it inspires appreciation and awe among children and non-scientists. Applied astronomy, with practical, real-world applications, can entice even the most utilitarian people to take notice and learn about the subject. Traditional celestial navigation is an astronomy topic that captures the attention of the public. The U.S. Naval Observatory has led the development of a publicly available online celestial navigation educational module titled, "Principles of Celestial Navigation". It can be used world-wide to introduce people to astronomy. This poster describes some of the aspects of this teaching module.

  9. An aid to tailoring the alar cartilages in tip rhinoplasty.

    Science.gov (United States)

    Cucin, R L

    1980-06-01

    An aid to achieving a more precisely symmetric and individualized result in tip rhinoplasty is presented as an aid to both neophytes and experienced surgeons. It is thought to be particularly helpful in teaching variations of tip rhinoplasty and anticipating the results of proper resection. PMID:7384286

  10. "Repellent and Shameful": The Portrayal of AIDS in "America Responds to AIDS" Broadcast Public Service Announcements, 1987-1992.

    Science.gov (United States)

    Swanson, Douglas J.

    To address a need for increased discussion of the dangers of Acquired Immune Deficiency Syndrome (AIDS) and an increased educative effort to prevent people from acquiring HIV infection, a study investigated one element of an AIDS campaign of the past: the "America Responds to AIDS" television and radio public service announcements (PSAs). Taking…

  11. Conceptual Model of Providing Traffic Navigation Services to Visually Impaired Persons

    OpenAIRE

    Periša, Marko; Peraković, Dragan; Šarić, Slavko

    2014-01-01

    In order to include people of reduced mobility in the traffic system it is necessary to provide accessibility and information of the users to all the facilities surrounding them. By analysing the currently available information and communication technologies a new conceptual model of providing navigation services to the visually impaired persons has been proposed. This model is based on Cloud Computing platform, and this research describes the method of navigating the users based on accurate ...

  12. Targeting of AID-mediated sequence diversification to immunoglobulin genes.

    Science.gov (United States)

    Kothapalli, Naga Rama; Fugmann, Sebastian D

    2011-04-01

    Activation-induced cytidine deaminase (AID) is a key enzyme for antibody-mediated immune responses. Antibodies are encoded by the immunoglobulin genes and AID acts as a transcription-dependent DNA mutator on these genes to improve antibody affinity and effector functions. An emerging theme in field is that many transcribed genes are potential targets of AID, presenting an obvious danger to genomic integrity. Thus there are mechanisms in place to ensure that mutagenic outcomes of AID activity are specifically restricted to the immunoglobulin loci. Cis-regulatory targeting elements mediate this effect and their mode of action is probably a combination of immunoglobulin gene specific activation of AID and a perversion of faithful DNA repair towards error-prone outcomes. PMID:21295456

  13. Experimental Study of Forces Exerted on Ships Due to the Vertical Walls of Navigation Channels

    Directory of Open Access Journals (Sweden)

    Mohammadreza Fathi Kazerooni

    2015-06-01

    Full Text Available Ship maneuvering in restricted waters of harbor basins and navigation channels had been the main concern in recent years due to sudden increase of ship’s size. When the ship enters a navigation channel the lateral boundary of the channel exerts a transverse force and turning moment on the ship hull. These forces are so important in the analysis of safety of ship navigation in the channels. Ship model test in the towing tank is a reliable method to evaluate these forces. Therefore systematic model tests are held for modeling of the forces exerted on the tanker ship and dhow model traveling alongside a vertical wall. A database of the interaction forces is developed and the specific hydrodynamic effects related to the phenomena are discussed. The results can be used for simulation of ship maneuvering and assessment of safety limits for navigation of ships alongside the quay walls and breakwaters.

  14. A two-class brain computer interface to freely navigate through virtual worlds.

    Science.gov (United States)

    Ron-Angevin, Ricardo; Díaz-Estrella, Antonio; Velasco-Alvarez, Francisco

    2009-06-01

    A brain computer interface that enables navigation through a virtual environment (VE) using four different navigation commands (turn right, turn left, move forward and move back) is presented. A graphical interface allows subjects to select a specific command. In this interface, the different navigation commands are surrounding a circle. A bar in the center of the circle is continuously rotating. The subject controls, by only two mental tasks, the bar extension to reach the chosen command. In this study, after an initial training based on three sessions, 8 out of 15 naive subjects were able to navigate through the VE discriminating between imagination of right-hand movements and relaxed state. All subjects (except one) improved their performance in each run and a mean error rate of 23.75% was obtained. PMID:19469662

  15. 14 CFR Appendix G to Part 121 - Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Doppler Radar and Inertial Navigation... OPERATIONS Pt. 121, App. G Appendix G to Part 121—Doppler Radar and Inertial Navigation System (INS): Request... Radar or Inertial Navigation System must submit a request for evaluation of the system to the...

  16. A Global Navigation Management Architecture Applied to Autonomous Robots in Urban Environments

    OpenAIRE

    Kenmogne, Ide-Flore; Alves De Lima, Danilo; Corrêa Victorino, Alessandro

    2015-01-01

    This paper presents a global behavioral architecture used as a coordinator for the global navigation of an autonomous vehicle in an urban context including traffic laws and other features. As an extension to our previous work, the approach presented here focuses on how this manager uses perceived information (from low cost cameras and laser scanners) combined with digital road-map data to take decisions. This decision consists in retrieving the car's state regarding the global navigation goal...

  17. Waved albatrosses can navigate with strong magnets attached to their head

    OpenAIRE

    Mouritsen, Henrik; Huyvaert, Kathryn P.; Frost, Barrie J.; Anderson, David J.

    2003-01-01

    The foraging excursions of waved albatrosses Phoebastria irrorata during incubation are ideally suited for navigational studies because they navigate between their Galápagos breeding site and one specific foraging site in the upwelling zone of Peru along highly predictable, straight-line routes. We used satellite telemetry to follow free-flying albatrosses after manipulating magnetic orientation cues by attaching magnets to strategic places on the birds' heads. All experimental, sham-manipula...

  18. Study Protocol: A randomized controlled trial of patient navigation-activation to reduce cancer health disparities

    Directory of Open Access Journals (Sweden)

    Rousseau Sally

    2010-10-01

    Full Text Available Abstract Background Cancer health disparities affecting low-income and minority patients are well documented. Root-causes are multifactorial, including diagnostic and treatment delays, social and financial barriers, and poor communication. Patient navigation and communication coaching (activation are potential interventions to address disparities in cancer treatment. The purpose of this clinical trial is to test the effectiveness of an intervention combining patient navigation and activation to improve cancer treatment. Methods/Design The Rochester Patient Navigation Research Program (PNRP is a National Cancer Institute-sponsored, patient-level randomized trial (RCT of patient navigation and activation, targeting newly-diagnosed breast and colorectal cancer patients in Rochester, NY. The goal of the program is to decrease cancer health disparities by addressing barriers to receipt of cancer care and promoting patient self-efficacy. The intervention uses trained, paraprofessional patient navigators recruited from the target community, and a detailed training and supervisory program. Recruited patients are randomly assigned to receive either usual care (except for baseline and follow-up questionnaires and interviews or intervention. The intervention patients receive tailored assistance from their patient navigators, including phone calls, in-person meetings, and behind-the-scenes coordination of care. A total of 344 patients have been recruited. Outcomes measured at three month intervals include timeliness of care, patient adherence, patient satisfaction, quality of life, self-efficacy, health literacy, and cancer knowledge. Discussion This unique intervention combining patient navigation and patient activation is designed to address the multifactorial problem of cancer health disparities. If successful, this study will affect the design and implementation of patient navigation programs. Trials Registration clinicaltrials.gov identifier NCT

  19. Marketing Merit Aid: The Response of Flagship Campuses to State Merit Aid Programs

    Science.gov (United States)

    Ness, Erik C.; Lips, Adam J. A.

    2011-01-01

    This study examines the differences in the portfolio of institutional scholarships and the marketing of these awards between flagship campuses with and without state merit aid programs. Using content analysis techniques to analyze institutional websites of the 16 Southern Regional Education Board (SREB) flagship campuses, three thematic responses…

  20. Image navigation as a means to expand the boundaries of fluorescence-guided surgery

    International Nuclear Information System (INIS)

    Hybrid tracers that are both radioactive and fluorescent help extend the use of fluorescence-guided surgery to deeper structures. Such hybrid tracers facilitate preoperative surgical planning using (3D) scintigraphic images and enable synchronous intraoperative radio- and fluorescence guidance. Nevertheless, we previously found that improved orientation during laparoscopic surgery remains desirable. Here we illustrate how intraoperative navigation based on optical tracking of a fluorescence endoscope may help further improve the accuracy of hybrid surgical guidance. After feeding SPECT/CT images with an optical fiducial as a reference target to the navigation system, optical tracking could be used to position the tip of the fluorescence endoscope relative to the preoperative 3D imaging data. This hybrid navigation approach allowed us to accurately identify marker seeds in a phantom setup. The multispectral nature of the fluorescence endoscope enabled stepwise visualization of the two clinically approved fluorescent dyes, fluorescein and indocyanine green. In addition, the approach was used to navigate toward the prostate in a patient undergoing robot-assisted prostatectomy. Navigation of the tracked fluorescence endoscope toward the target identified on SPECT/CT resulted in real-time gradual visualization of the fluorescent signal in the prostate, thus providing an intraoperative confirmation of the navigation accuracy. (paper)

  1. Image navigation as a means to expand the boundaries of fluorescence-guided surgery

    Science.gov (United States)

    Brouwer, Oscar R.; Buckle, Tessa; Bunschoten, Anton; Kuil, Joeri; Vahrmeijer, Alexander L.; Wendler, Thomas; Valdés-Olmos, Renato A.; van der Poel, Henk G.; van Leeuwen, Fijs W. B.

    2012-05-01

    Hybrid tracers that are both radioactive and fluorescent help extend the use of fluorescence-guided surgery to deeper structures. Such hybrid tracers facilitate preoperative surgical planning using (3D) scintigraphic images and enable synchronous intraoperative radio- and fluorescence guidance. Nevertheless, we previously found that improved orientation during laparoscopic surgery remains desirable. Here we illustrate how intraoperative navigation based on optical tracking of a fluorescence endoscope may help further improve the accuracy of hybrid surgical guidance. After feeding SPECT/CT images with an optical fiducial as a reference target to the navigation system, optical tracking could be used to position the tip of the fluorescence endoscope relative to the preoperative 3D imaging data. This hybrid navigation approach allowed us to accurately identify marker seeds in a phantom setup. The multispectral nature of the fluorescence endoscope enabled stepwise visualization of the two clinically approved fluorescent dyes, fluorescein and indocyanine green. In addition, the approach was used to navigate toward the prostate in a patient undergoing robot-assisted prostatectomy. Navigation of the tracked fluorescence endoscope toward the target identified on SPECT/CT resulted in real-time gradual visualization of the fluorescent signal in the prostate, thus providing an intraoperative confirmation of the navigation accuracy.

  2. Estimation with applications to tracking and navigation theory, algorthims and software

    CERN Document Server

    Bar-Shalom, Yaakov; Kirubarajan, Thiagalingam

    2001-01-01

    Expert coverage of the design and implementation of state estimation algorithms for tracking and navigation Estimation with Applications to Tracking and Navigation treats the estimation of various quantities from inherently inaccurate remote observations. It explains state estimator design using a balanced combination of linear systems, probability, and statistics. The authors provide a review of the necessary background mathematical techniques and offer an overview of the basic concepts in estimation. They then provide detailed treatments of all the major issues in estimatio

  3. Mars Rover Local Navigation And Hazard Avoidance

    Science.gov (United States)

    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.

  4. Mars rover local navigation and hazard avoidance

    Science.gov (United States)

    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.

  5. Participants' dynamic orientation to folder navigation when using a VOCA with a touch screen in talk-in-interaction.

    Science.gov (United States)

    Norén, Niklas; Svensson, Eva; Telford, Jeanette

    2013-03-01

    This paper reports on a conversation-analysis case study of interaction between a child with cerebral palsy and an adult using a computer-based voice output communication aid (VOCA) device with a touch-sensitive screen-input system. Data was collected from video recordings of everyday activities at school. The public nature of the VOCA-mediated turn construction process (hand movements towards the screen, on-screen folder navigation, synthetic speech) displays the projection of the turn under way and its possible continuations. The adult interlocutor orients to such projections when contributing to the topic of the ongoing turn and when initiating repair on its topical development. Contributing may activate the AAC user's further involvement in the ongoing turn, while repair may restrict the AAC user's influence on the topical progression. The findings are relevant for clinical assessment and intervention. PMID:23521350

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

    Science.gov (United States)

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

    2007-03-01

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

  7. 导航技术在颅底-颞下区肿瘤手术中的应用%Application of computer-aided design and navigation technology in skull base and infratemporal fossa tumor surgery

    Institute of Scientific and Technical Information of China (English)

    郭玉兴; 彭歆; 刘筱菁; 张雷; 俞光岩; 郭传殡

    2013-01-01

    Objective To evaluate the application of computer-aided design and navigation technology in skull base and infratemporal fossa tumor surgery and to analyze its advantages and disadvantages.Methods Twenty-nine cases with tumor of skull base and infratemporal fossa were treated with computer-aided design and navigation surgery.The Parameters of age,gender,primary or recurrent tumor,tumor nature and surgical approach were recorded.Results En bloc resection was performed in 20 cases and subtotal resection in 9 cases.The margin status was negative margin in 8 cases,near-tumor margin in 17 cases and positive resection margin in 4 cases.Postoperative complication rate was 14% (4/29).During the follow-up period,2 benign cases recurred.In the malignant group,there were 7 cases of recurrence,2 cases of metastasis and 3 deaths.The 5-year overall survival and progression-free survival rate were 69% and 40% respectively.Conclusions Navigation technology can enhance the confidence of the surgeons and operation safety in handling malignant tumors in skull base and infratemporal fossa.%目的 评价计算机辅助设计导航技术在颅底-颞下区肿瘤手术中的应用价值.方法 对29例颅底-颞下区肿瘤患者行计算机辅助手术方案设计及术中导航.记录患者的年龄、性别、肿瘤原发或复发、肿瘤性质及手术入路.应用SPSS 13.0软件计算生存率.结果 肿瘤完全切除20例、近全切除7例、次全切除2例;切除方式:整块切除20例、分块切除9例;切缘状态:阴性切缘8例、近肿瘤切除17例、阳性切缘4例.术后并发症发生率为14%(4/29).随访期内良性肿瘤复发2例.恶性肿瘤复发7例、转移2例、死亡3例,恶性肿瘤5年总生存率和无进展生存率分别为69%和40%.结论 计算机辅助设计导航技术可提高颅底-颞下区外科操作的手术安全性.

  8. Beijing Encourages High-Risk Groups to Undertake AIDS Test

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    High-risk groups in Beijing, China's capital city, such as sex workers, drug-takers who share needles and gay communities are being encouraged to take voluntary counseling and tests (VCT) as part of an effort to stem the spread of AIDS. Tens of thousands of flyers have been distributed to disease control centers at district levels, and they will be handed to high-risk individuals by AIDS workers and volunteers over the next few weeks.

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

    Science.gov (United States)

    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.

  10. Performance Indices to Aid Nuclear Material Safeguard Management Decisions

    OpenAIRE

    Lathrop, J.W.

    1981-01-01

    The management of a national or international nuclear material safeguard system involves large numbers of very complex strategic and tactical decisions at several organizational levels. This report outlines a decision analytic approach to developing decision aids to assist the various decision makers in the material accounting part of that process. The intent of the report is to layout a very general simple conceptual framework for such decision aids. While the framework combines the most bas...

  11. Climate Change, Green Growth and Aid Allocation to Poor Countries

    OpenAIRE

    Stefan Dercon

    2014-01-01

    With serious impacts of climate change looming in a few decades, but current poverty still high in the developing world, we ask how to spend development aid earmarked for the poor. Poverty reduction tends to be strongly linked to economic growth, but growth impacts the environment and increases CO2 emissions. So can greener growth that is more climate-resilient and less environmentally damaging deliver large scale poverty reduction? Can aid be used for effective poverty reduction now without ...

  12. Global inequality of life expectancy due to AIDS

    OpenAIRE

    Dorling, Danny; Shaw, Mary; Smith, George Davey

    2006-01-01

    Global inequality in both health and wealth began to rise worldwide in the early 1980s and has been exacerbated by AIDS in Africa. This trend is not inevitable, and historical trends show that inequality can be reduced

  13. Development of NASA's Space Communications and Navigation Test Bed Aboard ISS to Investigate SDR, On-Board Networking and Navigation Technologies

    Science.gov (United States)

    Reinhart, Richard C.; Kacpura, Thomas J.; Johnson, Sandra K.; Lux, James P.

    2010-01-01

    NASA is developing an experimental flight payload (referred to as the Space Communication and Navigation (SCAN) Test Bed) to investigate software defined radio (SDR), networking, and navigation technologies, operationally in the space environment. The payload consists of three software defined radios each compliant to NASA s Space Telecommunications Radio System Architecture, a common software interface description standard for software defined radios. The software defined radios are new technology developments underway by NASA and industry partners. Planned for launch in early 2012, the payload will be externally mounted to the International Space Station truss and conduct experiments representative of future mission capability.

  14. Foreign Aid Designed to Diminish Terrorist Atrocities can Increase Them

    OpenAIRE

    Spagat, M; Mandler, M.

    2004-01-01

    A domestic power faces an enemy and commits terrorist atrocities to increase the liklihood of victory. A foreign patron can grant aid to the power but prefers fewer or no atrocities. The domestic power responds by acquiescing in the creation of uncontrollable paramilitaries that commit even more atrocities. Once the paramilitaries are set up, aid flows and the atrocity level is high. Now suppose the foreign patron is uncertin whether the domextic power can control the paramilitaries. At a poo...

  15. Foreign Aid Designed to Diminish Terrorist Atrocities can Increase Them

    OpenAIRE

    Mandler, Michael; Spagat, Michael

    2003-01-01

    A domestic power faces an enemy and commits terrorist atrocities to increase the likelihood of victory. A foreign patron can grant aid to the power but prefers fewer or no atrocities. The domestic power responds by acquiescing in the creation of uncontrollable paramilitaries that commit even more atrocities. Once the paramilitaries are set up, aid flows and the atrocity level is high. Now suppose the foreign patron is uncertain whether the domestic power can control the paramilitaries. At a p...

  16. Enhanced differential evolution to combine optical mouse sensor with image structural patches for robust endoscopic navigation.

    Science.gov (United States)

    Luo, Xiongbiao; Jayarathne, Uditha L; McLeod, A Jonathan; Mori, Kensaku

    2014-01-01

    Endoscopic navigation generally integrates different modalities of sensory information in order to continuously locate an endoscope relative to suspicious tissues in the body during interventions. Current electromagnetic tracking techniques for endoscopic navigation have limited accuracy due to tissue deformation and magnetic field distortion. To avoid these limitations and improve the endoscopic localization accuracy, this paper proposes a new endoscopic navigation framework that uses an optical mouse sensor to measure the endoscope movements along its viewing direction. We then enhance the differential evolution algorithm by modifying its mutation operation. Based on the enhanced differential evolution method, these movement measurements and image structural patches in endoscopic videos are fused to accurately determine the endoscope position. An evaluation on a dynamic phantom demonstrated that our method provides a more accurate navigation framework. Compared to state-of-the-art methods, it improved the navigation accuracy from 2.4 to 1.6 mm and reduced the processing time from 2.8 to 0.9 seconds. PMID:25485397

  17. 50 YEARS OF CENTRAL GOVERNMENT Aid to Tibet(Ⅳ)——62 Aid Projects

    Institute of Scientific and Technical Information of China (English)

    GYIAREN

    2002-01-01

    In July 1994,the CPC Central Committee and the State Council held theThird National Conference on Work in Tibet.During the conference, JiangZemin,General Party Secretary and State President,said that showing carefor,and providing aid to Tibet constituted the consistent policy of the Partyand the State,and the bounden duty of peoples of all ethnic groups in the country.

  18. Voice Operated Outdoor Navigation System For Visually Impaired Persons

    Directory of Open Access Journals (Sweden)

    Somnath koley, Ravi Mishra

    2012-04-01

    Full Text Available —Blind People uses white canes to aid in obstacle detection & avoidance. Guide dogs can also be of limited aid for finding the way to a remote location. So our goal is to create a portable, simple less costly system that will allow Blind peoples to travel through familiar and unfamiliar environments without the aid of guides. Several guidance system has been developed for vision impaired people, but these systems tends to be expensive, also make use of a client server approach. This Navigation system consists of two distinct components: sensing of the immediate environment for blind people to travel (e.g., obstacles and hazards and navigating to remote destinations beyond the immediately perceptible environment. The paper described here focused on the development and evaluation of a Navigation system that makes use of GPS (the Global Positioning System, voice and ultrasonic sensor for obstacle detection.

  19. Eye Tracking to Explore the Impacts of Photorealistic 3d Representations in Pedstrian Navigation Performance

    Science.gov (United States)

    Dong, Weihua; Liao, Hua

    2016-06-01

    Despite the now-ubiquitous two-dimensional (2D) maps, photorealistic three-dimensional (3D) representations of cities (e.g., Google Earth) have gained much attention by scientists and public users as another option. However, there is no consistent evidence on the influences of 3D photorealism on pedestrian navigation. Whether 3D photorealism can communicate cartographic information for navigation with higher effectiveness and efficiency and lower cognitive workload compared to the traditional symbolic 2D maps remains unknown. This study aims to explore whether the photorealistic 3D representation can facilitate processes of map reading and navigation in digital environments using a lab-based eye tracking approach. Here we show the differences of symbolic 2D maps versus photorealistic 3D representations depending on users' eye-movement and navigation behaviour data. We found that the participants using the 3D representation were less effective, less efficient and were required higher cognitive workload than using the 2D map for map reading. However, participants using the 3D representation performed more efficiently in self-localization and orientation at the complex decision points. The empirical results can be helpful to improve the usability of pedestrian navigation maps in future designs.

  20. The Concept of “Apps” as a Tool to Improve Innovation in e-Navigation

    Directory of Open Access Journals (Sweden)

    Michael Bergmann

    2015-09-01

    Full Text Available The current systems supporting navigation on board of ships are built on the classic concept for equipment: The system is developed, tested, type approved, installed and from that time on used with no or little modifications. Looking at other industries a regime of software and system maintenance has been established which allows more rapid updates. The development in the IT arena moves more towards modular approached, encapsulating individual components for easier implementation and delivery with limited system wide impact. This key concept is lately often referred to as the “app concept”. The e-Navigation development asks for exactly that: a way to improve innovation while ensuring system stability for the navigational components used by the navigator on the bridge. A key aspect of the success of new systems will be the ability to convert data into as information as needed in any given situation, creating knowledge for intelligent decisions increasing the competence of a navigator. The paper will focus on the following topics: – The classic “monolithic” Equipment paradigm – Modern System Architecture using components and “apps”-concept – Advantages of an approach using situational driven tool enhancements – The “app”-concept supporting the situational centric information presentation

  1. Slime mold uses an externalized spatial "memory" to navigate in complex environments.

    Science.gov (United States)

    Reid, Chris R; Latty, Tanya; Dussutour, Audrey; Beekman, Madeleine

    2012-10-23

    Spatial memory enhances an organism's navigational ability. Memory typically resides within the brain, but what if an organism has no brain? We show that the brainless slime mold Physarum polycephalum constructs a form of spatial memory by avoiding areas it has previously explored. This mechanism allows the slime mold to solve the U-shaped trap problem--a classic test of autonomous navigational ability commonly used in robotics--requiring the slime mold to reach a chemoattractive goal behind a U-shaped barrier. Drawn into the trap, the organism must rely on other methods than gradient-following to escape and reach the goal. Our data show that spatial memory enhances the organism's ability to navigate in complex environments. We provide a unique demonstration of a spatial memory system in a nonneuronal organism, supporting the theory that an externalized spatial memory may be the functional precursor to the internal memory of higher organisms. PMID:23045640

  2. Navigation systems

    OpenAIRE

    Ocepek, Marjan

    2013-01-01

    In this thesis we present different navigation systems which may be used also in surveying. Map as a basis of navigation is described at the beginning. Next, we focus on navigation based on celestial bodies. We present basic terms such as navigation and orientation and describe some primitive methods, which had been used for orientation without compass. We present two important time keeping instruments that facilitated the process of position determination, the chronometer and chronograph, an...

  3. Adaptive iterated extended Kalman filter and its application to autonomous integrated navigation for indoor robot.

    Science.gov (United States)

    Xu, Yuan; Chen, Xiyuan; Li, Qinghua

    2014-01-01

    As the core of the integrated navigation system, the data fusion algorithm should be designed seriously. In order to improve the accuracy of data fusion, this work proposed an adaptive iterated extended Kalman (AIEKF) which used the noise statistics estimator in the iterated extended Kalman (IEKF), and then AIEKF is used to deal with the nonlinear problem in the inertial navigation systems (INS)/wireless sensors networks (WSNs)-integrated navigation system. Practical test has been done to evaluate the performance of the proposed method. The results show that the proposed method is effective to reduce the mean root-mean-square error (RMSE) of position by about 92.53%, 67.93%, 55.97%, and 30.09% compared with the INS only, WSN, EKF, and IEKF. PMID:24693225

  4. Adaptive Iterated Extended Kalman Filter and Its Application to Autonomous Integrated Navigation for Indoor Robot

    Directory of Open Access Journals (Sweden)

    Yuan Xu

    2014-01-01

    Full Text Available As the core of the integrated navigation system, the data fusion algorithm should be designed seriously. In order to improve the accuracy of data fusion, this work proposed an adaptive iterated extended Kalman (AIEKF which used the noise statistics estimator in the iterated extended Kalman (IEKF, and then AIEKF is used to deal with the nonlinear problem in the inertial navigation systems (INS/wireless sensors networks (WSNs-integrated navigation system. Practical test has been done to evaluate the performance of the proposed method. The results show that the proposed method is effective to reduce the mean root-mean-square error (RMSE of position by about 92.53%, 67.93%, 55.97%, and 30.09% compared with the INS only, WSN, EKF, and IEKF.

  5. Research on Web Navigations

    Directory of Open Access Journals (Sweden)

    Qian Zhongsheng

    2011-10-01

    Full Text Available Web applications employ various new languages, technologies, and programming models to implement applications with very high quality requirements. In building Web applications, three types of models must be considered, which are conceptual model, navigation model and presentation model. Navigation problems are significant among them that must be confronted. This work illuminates three different classifications of Web navigations as well as their feature, analyzes and compares various popular Web navigation models. Moreover, it also presents and suggests some guidelines for Web navigation design based on Web development design pattern experiences.

  6. Experimental validation of radiographic 3D navigation of the laser catheter to the target site

    International Nuclear Information System (INIS)

    The present experimental study determined the feasibility and accuracy of online radiographic 3D localization for device navigation. Such a procedure is based on radiographic image pairs and corresponding projection data. An automatic data and image acquision system was developed to perform online measurements. Image errors caused by geomagnetism were compensated instrumentally. A centimeter grid and an attached laser catheter were imaged in common biplane projections. Possible ablation sites on the grid were sequentially localized from the acquired image pairs. The 3D coordinates computed with reference to the catheter tip were compared with their true coordinates. The mean± SD of the measurement time and localization error were calculated. The 3D localization took 10 ± 2 sec. The overall absolute localization error was 0,61 ± 0,32 mm. The time frame and accuracy of the 3D localization make a radiographic catheter navigation feasible. Further development towards a navigation system for routine use is justified. (author)

  7. Design and development of adapters for electromagnetic trackers to perform navigated laparoscopic radiofrequency ablation

    Directory of Open Access Journals (Sweden)

    Schweikard Achim

    2007-10-01

    Full Text Available Abstract Background Laparoscopic radiofrequency ablation (RFA is an accepted approach to treat unresectable liver tumours distinguishing itself from other techniques by combining minimal invasiveness and the advantages of a surgical approach. The major task of laparoscopic RFA is the accurate needle placement to achieve complete tumour ablation. The use of an ultrasound-based, laparoscopic online-navigation system could increase the safety and accuracy of punctures. To connect such a system with the laparoscopic ultrasound (LUS transducer or the RFA needle especially designed adapters are needed. In this article we present our first experiences and prototypes for different sterilizable adapters for an electromagnetic navigation system for laparoscopic RFA. Methods All adapters were constructed with the help of a standard 3D CAD software. The adapters were built from medical stainless steel alloys and polyetherketone (PEEK. Prototypes were built in aluminium and polyoxymethilen (POM. We have designed and developed several adapters for the connection of electromagnetical tracking systems with different RFA needles and a laparoscopic ultrasound transducers. Results Based on earlier experiences of the initial version of the adapter, sterilisable adapters have been developed using biocompatible materials only. After short introduction, the adapters could be mounted to the laparoscopic ultrasound probe and the RFA needle under sterile conditions without any difficulties. Laboratory tests showed no disturbance of laparoscopic navigation system by the adapters. Anatomic landmarks in the liver could be safely reached. The adapters showed good feasibility, ergonomics, sterilizability and stability. Conclusion The development of usable adapters is the prerequisite for accurate tracking of a RFA needle for laparoscopic navigation purposes as well as 3D navigated ultrasound data acquisition. We designed, tested and used different adapters for the use of a

  8. Host genetic factors in susceptibility to HIV-1 infection and progression to AIDS

    Indian Academy of Sciences (India)

    Koushik Chatterjee

    2010-04-01

    HIV-1 infection has rapidly spread worldwide and has become the leading cause of mortality in infectious diseases. The duration for development of AIDS (AIDS progression) is highly variable among HIV–1 infected individuals, ranging from 2–3 years to no signs of AIDS development in the entire lifetime. Several factors regulate the rate at which HIV-1 infection progresses to AIDS. Host genetic factors play an important role in the outcome of such complex or multifactor diseases as AIDS and are also known to regulate the rate of disease progression. This review focuses on the major host genes reported to affect the progression to AIDS in HIV-1 infected individuals.

  9. RV-Xplorer: A Way to Navigate Lattice-Based Views over RDF Graphs

    OpenAIRE

    Alam, Mehwish; Napoli, Amedeo; Osmuk, Matthieu

    2015-01-01

    More and more data are being published in the form of machine readable RDF graphs over Linked Open Data (LOD) Cloud accessible through SPARQL queries. This study provides interactive navigation of RDF graphs obtained by SPARQL queries using Formal Concept Analysis. With the help of this {\\tt View By} clause a concept lattice is created as an answer to the SPARQL query which can then be visualized and navigated using RV-Xplorer (Rdf View eXplorer). Accordingly, this paper discusses the support...

  10. Solution to the problem of the close integration of satellite and inertial platform navigation systems

    Science.gov (United States)

    Pogorelov, V. A.; Sokolov, S. V.

    2015-11-01

    The problem of the close integration of a satellite and inertial navigation system (NA) constructed on the basis of a gyro-stabilized platform is solved. The features of the synthesis of an algorithm for nonlinear estimation of the NS state vector in view of the continuous character for the autonomous measurements and the discrete character for satellite measurements are studied. The developed algorithm for solving the navigation problem on the basis of the integrated NS allows one to provide a stable high-precision estimation of the parameters of motion for a movable object, including in the absence of satellite signals.

  11. Task-Based Navigation of a Taxonomy Interface to a Digital Repository

    Science.gov (United States)

    Khoo, Christopher S. G.; Wang, Zhonghong; Chaudhry, Abdus Sattar

    2012-01-01

    Introduction: This is a study of hierarchical navigation; how users browse a taxonomy-based interface to an organizational repository to locate information resources. The study is part of a project to develop a taxonomy for an library and information science department to organize resources and support user browsing in a digital repository.…

  12. The effects of information about AIDS risk and self-efficacy on women's intentions to engage in AIDS preventive behavior

    NARCIS (Netherlands)

    Yzer, MC; Fisher, JD; Bakker, AB; Siero, FW; Misovich, SJ

    1998-01-01

    Female college students' perceived vulnerability to AIDS and their perceived self-efficacy regarding AIDS preventive behavior (APB), were manipulated in a 2 x 2 design. Consistent with protection motivation theory (e.g.. Rogers, 1983), the results showed that intention to engage in APE was highest a

  13. Video Now Available to Help You Navigate the Poster Website | Poster

    Science.gov (United States)

    Having trouble finding a Poster article on a specific topic? Don’t know where to look for the Poster Puzzler? Want to comment on an article that you especially liked? Now you can learn how to navigate the Poster newsletter by viewing a video that walks you through all the features of the newsletter site.

  14. Micro-navigation for urban bus passengers: using the Internet of Things to improve the public transport experience

    OpenAIRE

    Foell, Stefan; Kortuem, Gerd; Rawassizadeh, Reza; Handte, Marcus; Iqbal, Umer; Marron, Pedro

    2014-01-01

    Public bus services are widely deployed in cities around the world because they provide cost-effective and economic public transportation. However, from a passenger point of view urban bus systems can be complex and difficult to navigate, especially for disadvantaged users, i.e. tourists, novice users, older people, and people with impaired cognitive or physical abilities. We present Urban Bus Navigator (UBN), a reality-aware urban navigation system for bus passengers with the ability to reco...

  15. CAD/CAM (Computer Aided Design/Computer Aided Manufacture). A Brief Guide to Materials in the Library of Congress.

    Science.gov (United States)

    Havas, George D.

    This brief guide to materials in the Library of Congress (LC) on computer aided design and/or computer aided manufacturing lists reference materials and other information sources under 13 headings: (1) brief introductions; (2) LC subject headings used for such materials; (3) textbooks; (4) additional titles; (5) glossaries and handbooks; (6)…

  16. Beyond the first 25 years: The International AIDS Society and its role in the global response to AIDS

    Directory of Open Access Journals (Sweden)

    McClure Craig

    2006-12-01

    Full Text Available Abstract Dr. Pedro Cahn, International AIDS Society (IAS President and Mr. Craig McClure, IAS Executive Director, provide their thoughts and analysis on the current and future role of the IAS as part of the global response to HIV/AIDS.

  17. Landmarks or panoramas: what do navigating ants attend to for guidance?

    Directory of Open Access Journals (Sweden)

    Beugnon Guy

    2011-08-01

    Full Text Available Abstract Background Insects are known to rely on terrestrial landmarks for navigation. Landmarks are used to chart a route or pinpoint a goal. The distant panorama, however, is often thought not to guide navigation directly during a familiar journey, but to act as a contextual cue that primes the correct memory of the landmarks. Results We provided Melophorus bagoti ants with a huge artificial landmark located right near the nest entrance to find out whether navigating ants focus on such a prominent visual landmark for homing guidance. When the landmark was displaced by small or large distances, ant routes were affected differently. Certain behaviours appeared inconsistent with the hypothesis that guidance was based on the landmark only. Instead, comparisons of panoramic images recorded on the field, encompassing both landmark and distal panorama, could explain most aspects of the ant behaviours. Conclusion Ants navigating along a familiar route do not focus on obvious landmarks or filter out distal panoramic cues, but appear to be guided by cues covering a large area of their panoramic visual field, including both landmarks and distal panorama. Using panoramic views seems an appropriate strategy to cope with the complexity of natural scenes and the poor resolution of insects' eyes. The ability to isolate landmarks from the rest of a scene may be beyond the capacity of animals that do not possess a dedicated object-perception visual stream like primates.

  18. A Discussion on e-Navigation and Implementation in Turkey

    Directory of Open Access Journals (Sweden)

    Y.V. Aydogdu

    2014-03-01

    Full Text Available Electronic navigation, which has great important for ship management, has taken a step with technological improvements. In the result of these enhancements, new systems appeared as well as existing systems and these systems began to be integrated each other or used data of obtaining from the others like that AIS, Radar, ECDIS etc. All these and likely future systems have been put together under the roof of enhanced navigation (e-navigation is defined by organizations such as International Maritime Organization (IMO, International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA, General Lighthouse Authority (GLA etc. Especially IALA guidelines serve as model future applications in Turkish waterways. In this study aim to redefine e-navigation concept based on maritime safety awareness, maritime service portfolio (MSC 85/26 and discuss possible applications.

  19. The impact of aid chains: relations of dependence or supportive partnerships for community-led responses to HIV/AIDS?

    Science.gov (United States)

    Aveling, E L

    2010-01-01

    In the context of increasing global emphasis on partnerships between international, governmental and civil society organisations in the distribution of international aid, this paper examines the ways in which the resulting aid chains promote and undermine community-led responses to HIV/AIDS. The impact of the aid-granting system is examined using an ethnographic case study of an HIV/AIDS prevention programme with Cambodian military families. The case study draws on observations of stakeholder meetings and programme activities, interviews with stakeholders (the donor, NGOs and military community) and textual materials (programme guidelines, policies and reports). Campbell et al.'s interrelated concepts of relational, symbolic and material context are used to frame the analysis. The establishment of a relationship with a more powerful international NGO is shown to be beneficial to the military community and civil society groups. The international NGO uses its significant material and economic leverage to improve the community's relational context (by ensuring the support of the military high command), symbolic context (by strengthening the position of community and civil society partners in relation to government bodies) and material context (through increasing access to health services). However, material and symbolic asymmetries between partners in the aid chain persist, curtailing the community's involvement and leadership. At the material and relational levels, the hierarchical flow of aid encourages accountability to the demands of the donor while excluding grassroots groups from directly accessing funding. At the symbolic level, problem-focused representations of the military further reinforce the community's position as recipients of intervention, which undermines recognition for the community's knowledge, strengths and right to fully participate. Thus while aid chains can be supportive of community-led responses, this analysis highlights how the structures

  20. SLAM algorithm applied to robotics assistance for navigation in unknown environments

    Directory of Open Access Journals (Sweden)

    Lobo Pereira Fernando

    2010-02-01

    Full Text Available Abstract Background The combination of robotic tools with assistance technology determines a slightly explored area of applications and advantages for disability or elder people in their daily tasks. Autonomous motorized wheelchair navigation inside an environment, behaviour based control of orthopaedic arms or user's preference learning from a friendly interface are some examples of this new field. In this paper, a Simultaneous Localization and Mapping (SLAM algorithm is implemented to allow the environmental learning by a mobile robot while its navigation is governed by electromyographic signals. The entire system is part autonomous and part user-decision dependent (semi-autonomous. The environmental learning executed by the SLAM algorithm and the low level behaviour-based reactions of the mobile robot are robotic autonomous tasks, whereas the mobile robot navigation inside an environment is commanded by a Muscle-Computer Interface (MCI. Methods In this paper, a sequential Extended Kalman Filter (EKF feature-based SLAM algorithm is implemented. The features correspond to lines and corners -concave and convex- of the environment. From the SLAM architecture, a global metric map of the environment is derived. The electromyographic signals that command the robot's movements can be adapted to the patient's disabilities. For mobile robot navigation purposes, five commands were obtained from the MCI: turn to the left, turn to the right, stop, start and exit. A kinematic controller to control the mobile robot was implemented. A low level behavior strategy was also implemented to avoid robot's collisions with the environment and moving agents. Results The entire system was tested in a population of seven volunteers: three elder, two below-elbow amputees and two young normally limbed patients. The experiments were performed within a closed low dynamic environment. Subjects took an average time of 35 minutes to navigate the environment and to learn how

  1. Origins of HIV and the evolution of resistance to AIDS.

    Science.gov (United States)

    Heeney, Jonathan L; Dalgleish, Angus G; Weiss, Robin A

    2006-07-28

    The cross-species transmission of lentiviruses from African primates to humans has selected viral adaptations which have subsequently facilitated human-to-human transmission. HIV adapts not only by positive selection through mutation but also by recombination of segments of its genome in individuals who become multiply infected. Naturally infected nonhuman primates are relatively resistant to AIDS-like disease despite high plasma viral loads and sustained viral evolution. Further understanding of host resistance factors and the mechanisms of disease in natural primate hosts may provide insight into unexplored therapeutic avenues for the prevention of AIDS. PMID:16873637

  2. Construction of Cognitive Maps to Improve E-Book Reading and Navigation

    Science.gov (United States)

    Li, Liang-Yi; Chen, Gwo-Dong; Yang, Sheng-Jie

    2013-01-01

    People have greater difficulty reading academic textbooks on screen than on paper. One notable problem is that they cannot construct an effective cognitive map because of the lack of contextual information cues and ineffective navigational mechanisms in e-books. To support the construction of cognitive maps, this paper proposes the visual cue map,…

  3. Using Therapeutic Letters to Navigate Resistance and Ambivalence: Experiential Implications for Group Counseling

    Science.gov (United States)

    Hagedorn, W. Bryce

    2011-01-01

    Clients in the early stages of changing addictive behaviors are typically not ready to assume active roles in making significant changes. Navigating these challenges with traditional talk therapy can prove ineffective. Experiential group activities help normalize the difficulties associated with making changes and help clinicians bypass client…

  4. 14 CFR Appendix A to Part 63 - Test Requirements for Flight Navigator Certificate

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Test Requirements for Flight Navigator Certificate A Appendix A to Part 63 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF.... A guide sheet may be used for this test. (27) Demonstrate a knowledge of the basic principle...

  5. An Analytical Approach to Avoid Obstacles in Mobile Robot Navigation

    OpenAIRE

    Alexandre Santos Brandão; Mário Sarcinelli-Filho; Ricardo Carelli

    2013-01-01

    A nonlinear supervised globally stable controller is proposed to reactively guide a mobile robot to avoid obstacles while seeking a goal. Whenever the robot detects an object nearby, its orientation is changed to be aligned with the tangent to the border of the obstacle. Then, the robot starts following it, looking for a feasible path to its goal. The supervisor is responsible for deciding which path to take when the robot faces some particular obstacle configurations that are quite difficult...

  6. Real-time Imaging Orientation Determination System to Verify Imaging Polarization Navigation Algorithm.

    Science.gov (United States)

    Lu, Hao; Zhao, Kaichun; Wang, Xiaochu; You, Zheng; Huang, Kaoli

    2016-01-01

    Bio-inspired imaging polarization navigation which can provide navigation information and is capable of sensing polarization information has advantages of high-precision and anti-interference over polarization navigation sensors that use photodiodes. Although all types of imaging polarimeters exist, they may not qualify for the research on the imaging polarization navigation algorithm. To verify the algorithm, a real-time imaging orientation determination system was designed and implemented. Essential calibration procedures for the type of system that contained camera parameter calibration and the inconsistency of complementary metal oxide semiconductor calibration were discussed, designed, and implemented. Calibration results were used to undistort and rectify the multi-camera system. An orientation determination experiment was conducted. The results indicated that the system could acquire and compute the polarized skylight images throughout the calibrations and resolve orientation by the algorithm to verify in real-time. An orientation determination algorithm based on image processing was tested on the system. The performance and properties of the algorithm were evaluated. The rate of the algorithm was over 1 Hz, the error was over 0.313°, and the population standard deviation was 0.148° without any data filter. PMID:26805851

  7. GP consortia: navigating ambiguity to produce greater public value?

    Science.gov (United States)

    Holbeche, Linda

    2011-05-01

    The UK's NHS is about to be significantly remodelled according to a white paper published in July 2010 that outlines the devolution of commissioning responsibilities away from strategic health authorities and primary care trusts to consortia of GPs, which are to be established at local level. Details of how the new GP consortia will operate are as yet unclear, but in essence they will be strategic alliances and it is likely that they will develop more or less formal arrangements between consortia partners, such as those of a commercial joint venture. This article draws on primary research into strategic alliances between organizations in all sectors. It suggests that there can be significant challenges for those working within strategic alliances, given that these tend to be beset by ambiguity and political tensions. In a context of ever greater transparency and accountability, it will be crucial to attend to the human aspects of strategic alliances since these represent significant risk if neglected. Conversely, alliances also offer the opportunity to develop the synergy of people, organizations and communities to deliver greater public value. Successful collaborations need to get three things right: governance, operations and behaviours. Relationships between consortia partners have a significant bearing on their ability to deliver desired outcomes. They must be able to build and maintain trust. Consortia partners will need sophisticated negotiating and stakeholder management skills and must be able to engage the public in setting the strategic goals for which they will be accountable. They also need strategic and operational management skills and must be able to cope with ambiguity and manage complexity. This paper argues that specific forms of leadership are needed in collaborative arrangements to mobilize people for positive action. People must work together by willingly and effectively pooling their initiative and expertise, and create a product or energy

  8. An Analytical Approach to Avoid Obstacles in Mobile Robot Navigation

    Directory of Open Access Journals (Sweden)

    Alexandre Santos Brandão

    2013-06-01

    Full Text Available A nonlinear supervised globally stable controller is proposed to reactively guide a mobile robot to avoid obstacles while seeking a goal. Whenever the robot detects an object nearby, its orientation is changed to be aligned with the tangent to the border of the obstacle. Then, the robot starts following it, looking for a feasible path to its goal. The supervisor is responsible for deciding which path to take when the robot faces some particular obstacle configurations that are quite difficult to deal with. Several simulations and experiments were run to validate the proposal, some of which are discussed here. To run the experiments, the proposed controller is programmed into the onboard computer of a real unicycle mobile platform, equipped with a laser range scanner. As for the simulations, the models of the same experimental setup were used. The final conclusion is that the nonlinear supervised controller proposed to solve the problem of avoiding obstacles during goal seeking has been validated, based on the theoretical analysis, and the simulated and experimental results.

  9. The TETRAD Project: Constraint Based Aids to Causal Model Specification.

    Science.gov (United States)

    Scheines, Richard; Spirtes, Peter; Glymour, Clark; Meek, Christopher; Richardson, Thomas

    1998-01-01

    The TETRAD for constraint-based aids to causal model specification project and related work in computer science aims to apply standards of rigor and precision to the problem of using data and background knowledge to make inferences about a model's specifications. Several algorithms that are implemented in the TETRAD II program are presented. (SLD)

  10. Guide to Implementing TAP. Teens for AIDS Prevention Project.

    Science.gov (United States)

    Center for Population Options, Washington, DC.

    Teens for AIDS Prevention (TAP) is a model peer intervention program designed by the Center for Population Options to increase knowledge and change attitudes and behaviors among youth to reduce their risk of Human Immunodeficiency Virus (HIV) infection. The program utilizes peer pressure in a positive sense: to encourage youth to protect…

  11. Early Childhood Teachers' Behavior Intention to Apply Teaching Aids

    Science.gov (United States)

    Kuo, Chuen-Tzay

    2010-01-01

    This research aimed to investigate the behavior intention of early childhood teachers to apply teaching aids. The survey method was used to collect data from 281 early childhood teachers currently working at early childhood education institutes. The data was analyzed by t-test, Chi-square analysis, and Pearson coefficient to examine the…

  12. Egocentric information helps desert ants to navigate around familiar obstacles.

    OpenAIRE

    Bisch-Knaden, S.; Wehner, R.

    2001-01-01

    Homing ants have been shown to associate directional information with familiar landmarks. The sight of these local cues might either directly guide the path of the ant or it might activate a landmark-based vector that points towards the goal position. In either case, the ants define their courses within allocentric systems of reference. Here, we show that desert ants, Cataglyphis fortis, forced to run along a devious path can use egocentric information as well. The ants were trained to deviat...

  13. Navigating the Race to the Top Traffic Jam

    Science.gov (United States)

    National Council on Teacher Quality, 2010

    2010-01-01

    Early last week the U.S. Department of Education announced an unexpected 16 finalists for the first round of Race to the Top (RTT) funding--a veritable traffic jam in the Race to the Top. The finalists have requested a total of $6.5 billion in funds, but only $4.3 billion is up for grabs, and that needs to be spread over two rounds of competition.…

  14. Object Detection Applied to Indoor Environments for Mobile Robot Navigation.

    Science.gov (United States)

    Hernández, Alejandra Carolina; Gómez, Clara; Crespo, Jonathan; Barber, Ramón

    2016-01-01

    To move around the environment, human beings depend on sight more than their other senses, because it provides information about the size, shape, color and position of an object. The increasing interest in building autonomous mobile systems makes the detection and recognition of objects in indoor environments a very important and challenging task. In this work, a vision system to detect objects considering usual human environments, able to work on a real mobile robot, is developed. In the proposed system, the classification method used is Support Vector Machine (SVM) and as input to this system, RGB and depth images are used. Different segmentation techniques have been applied to each kind of object. Similarly, two alternatives to extract features of the objects are explored, based on geometric shape descriptors and bag of words. The experimental results have demonstrated the usefulness of the system for the detection and location of the objects in indoor environments. Furthermore, through the comparison of two proposed methods for extracting features, it has been determined which alternative offers better performance. The final results have been obtained taking into account the proposed problem and that the environment has not been changed, that is to say, the environment has not been altered to perform the tests. PMID:27483264

  15. From Apprenticeship to Higher Education: Navigating the Credential Landscape

    Science.gov (United States)

    Dismore, Harriet

    2014-01-01

    The credential landscape of vocational and higher education in the UK has expanded in recent years, alongside a rise in the number of students undertaking qualifications and a steady increase in tuition fees. The transition from an apprenticeship to higher education is one example of the progression from vocational to higher education. However,…

  16. SOR Users` Guide : How to Navigate Through the SOR Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1996-08-01

    The Columbia River System Operation Review (SOR) gave river managers, users, and the general public a chance to examine system operations in detail, to study how each river use affects others, and to consider the consequences of changing the way the system works. The task was enormous, and it was a multiyear undertaking. In its wake, the SOR left a multitude of documents and six years of analysis that can and should be used broadly for other reference and research purposes. This catalog will introduce you to numerous SOR products to be found throughout the 20 appendices and the Final Environmental Impact Statement (EIS) Main Report. They include maps, models, data bases, current descriptions of Federal hydro projects and river resources, publications, and slide shows.

  17. Threats to the safety of navigation resulting from the tsunami

    Directory of Open Access Journals (Sweden)

    Bernard WIŚNIEWSKI

    2008-01-01

    Full Text Available The tsunami traveling times were examined in connection to the earthquake that took place on 26 December 2004 in the Indian Ocean, changing the sea level as far as the Atlantic. For 17 ports located on the coasts of the two oceans theoretical times of wave arrival at the ports were calculated and compared with the real data recorded bymareographs. It has been found that the theoretical and real times differed, which can be explained by the effect of shallow water. Furthermore, as regards to the earthquake itself, instead of a single point epicenter as it was reported, it should have been considered as a zone of continental plates subduction extending 1200 km. The tsunami speed averaged for 17 ports amounted to 682 km/h, which necessitates an alteration of the coefficient in the formula (2 from the existing 5.0 to 4.38.

  18. Navigating Bioenergy. Contributing to informed decision making on bioenergy issues

    Energy Technology Data Exchange (ETDEWEB)

    Vis, M.; Reumerman, P.; Frederiks, B. [BTG Biomass Technology Group, Enschede (Netherlands)

    2009-11-15

    In order to further contribute to sustainable global bioenergy development, UNIDO will this year be launching the Bioenergy Capacity Building Programme (BIOCAB), offering a comprehensive training package to policy makers and entrepreneurs aimed at enhancing their engagement in shaping a sustainable bioenergy industry in developing countries. The training package, disseminated through a network of key institutions and certified trainers, will consist of four modules covering the following subjects: Technologies and Processes, Policy, Socio-Economic and Environmental Issues, Financial and Project Development Issues, Industrial Applications for Productive Use. While designing the training package and its modules at a meeting hosted by UNIDO at headquarters in August 2008, experts reiterated a demand, previously expressed by UNIDO clients at various international fora, for an easy-to-read, practical and user-friendly introduction to certain contentious bioenergy issues. The expert meeting selected the most hotly-debated bioenergy issues and came up with the following eight topics: (1) Jatropha, the feedstock of the future?; (2) Biomethane, is it an underestimated energy source?; (3) Energy from Municipal Solid Waste, can this potential be realized?; (4) The Biorefinery Concept, how relevant is it for developing countries?; (5) Competition with Food, what are the facts in the food versus fuel discussion?; (6) Sustainability and Certification of Biomass, what are the benefits?; (7) Clean Development Mechanism, how does it work?; (8) Success Stories.

  19. Machine Vision Applied to Navigation of Confined Spaces

    Science.gov (United States)

    Briscoe, Jeri M.; Broderick, David J.; Howard, Ricky; Corder, Eric L.

    2004-01-01

    The reliability of space related assets has been emphasized after the second loss of a Space Shuttle. The intricate nature of the hardware being inspected often requires a complete disassembly to perform a thorough inspection which can be difficult as well as costly. Furthermore, it is imperative that the hardware under inspection not be altered in any other manner than that which is intended. In these cases the use of machine vision can allow for inspection with greater frequency using less intrusive methods. Such systems can provide feedback to guide, not only manually controlled instrumentation, but autonomous robotic platforms as well. This paper serves to detail a method using machine vision to provide such sensing capabilities in a compact package. A single camera is used in conjunction with a projected reference grid to ascertain precise distance measurements. The design of the sensor focuses on the use of conventional components in an unconventional manner with the goal of providing a solution for systems that do not require or cannot accommodate more complex vision systems.

  20. Neutron activation analysis - an aid to forensic science

    International Nuclear Information System (INIS)

    Forensic Science is oriented towards the examination of evidence specimens, collected from a scene of crime in order to establish the link between the criminal and the crime. This science therefore has a profound role to play in criminal justice delivery system. The importance of neutron activation analysis (NAA) as a specialised technique to aid crime investigation has emerged and has been recognised

  1. Evaluation of several navigation algorithms for application to general aviation

    Science.gov (United States)

    Conrad, B.; Korsak, A. J.; Jackson, C. T., Jr.

    1975-01-01

    Using data obtained in flight, three position determining algorithms for use by general aviation aircraft were evaluated representing increasing software requirements. These were a DME only, DME/air data and blended DME/air data. Although each step represented additional software with resultant increase in position accuracy, all could be performed on a programmable electronic desk calculator. Results from the computation of aircraft position using the three algorithms are presented. The algorithms employed can be extended to accept VOR, TACAN bearing, ADF, or other NAVAID Data. To obtain the flight data an experimental system was configured and flown on a general aviation aircraft. Principal hardware elements (all with low-cost potential) were a programmable calculator, a single DME receiver (multiplexed for multiple DME use) and a low-cost air speed sensor (shed-vortex principle). The flight test demonstrated satisfactory performance of these principal elements.

  2. Types of Hearing Aids

    Science.gov (United States)

    ... Devices Consumer Products Hearing Aids Types of Hearing Aids Share Tweet Linkedin Pin it More sharing options ... some features for hearing aids? What are hearing aids? Hearing aids are sound-amplifying devices designed to ...

  3. Web Usage Mining Applied to Records of Navigation by Internet

    Directory of Open Access Journals (Sweden)

    Darian Horacio Grass Boada

    2013-06-01

    Full Text Available This paper presents a Knowledge Discovery on Databases (KDD process applied on the internetsurfing logs at the University of Informatics Sciences. In this context, it describes a Web-UsageMining process using as data sources; the internet surfing logs stored by the proxy server, and alsodescriptive information regarding the users of such surfing service, which was provided by the institution’spersonnel management systems. Statistical, numerical and clustering techniques were combinedseeking to identify user groups with similar internet surfing account usage, in hopes of providingimportant information for decision making processes carried out by the Network Management andSecurity Office or other areas of the institution. This paper describes the methods and techniquesused, and the procedure utilized for performing the descriptive clustering task. This procedure proposesthe use of the CUR matricial decomposition to identify the possible number of groups to identify by thek-medoides clustering algorithm. Lastly, the experiments carried out and the evaluations of the groupsobtained are described and examples of some of the patterns obtained are presented.

  4. Three dimensional creativity three navigations to extend our thoughts

    CERN Document Server

    Lee, Kwang Hyung

    2014-01-01

    Is creativity something that we are simply born with and cannot hone with effort? Some say that creativity cannot be cultivated. Is it true? In general, our thinking sticks to reality unless there is any external stimulation. With our thinking fixed on a certain situation, it becomes difficult to come up with a fresh idea. In this regard, three questions are suggested: (1) Question of Time: When a problem arises, question yourself on a time axis first of all. How would the matter be handled 10 or 20 years from now? (2) Question of Space: Ask yourself some questions on its spatial elements. How would the matter be handled in Saudi Arabia or in China? (3) Question of Field: Apply the given problem in a variety of fields. How would the matter be handled in the field of music or electronic engineering? The three questions suggested here are given on the three axes: time, space, and field, and this book deals with theoretical and practical aspects on the topics. In this way it is a unique book about the systematic...

  5. An Aid to Neuro-Ophthalmology

    OpenAIRE

    Akram, Muhammad

    2011-01-01

    Muhammad Shoaib AkramDepartment of Ophthalmology, King Fahad Military Hospital, Khamis Mushyat, Saudi ArabiaNeuro-ophthalmology is a very interesting field. Localizing a lesion in various pathways can be challenging, particularly for beginners. One needs a solid foundation of the neuro-anatomy of visual pathways to enhance understanding. The author aims to provide medical students and residents with the basic concepts of neuro-ophthalmology. This text attempts to simplify the complex problems...

  6. HIV and AIDS: Medicines to Help You

    Science.gov (United States)

    ... to treat HIV are called "antiretroviral treatment' or ART. There are different kinds of ART medicines. People with HIV may need to take ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  7. Electrical Stimulation as an Aid to Speechreading.

    Science.gov (United States)

    Tyler, Richard S.; And Others

    1988-01-01

    This paper, discussing use of electrical stimulation by postlingually deafened adults to supplement speechreading, focuses on: information conveyed by vision, acoustic information needed to resolve visual confusions, basic psychophysical abilities of cochlear implant patients, auditory-alone and audiovisual perception by cochlear-implant patients,…

  8. An Introduction to Neural Networks for Hearing Aid Noise Recognition.

    Science.gov (United States)

    Kim, Jun W.; Tyler, Richard S.

    1995-01-01

    This article introduces the use of multilayered artificial neural networks in hearing aid noise recognition. It reviews basic principles of neural networks, and offers an example of an application in which a neural network is used to identify the presence or absence of noise in speech. The ability of neural networks to "learn" the characteristics…

  9. Radiation as an aid to analysis

    International Nuclear Information System (INIS)

    Radiochemical methods of analysis possess some special advantages, such as rapidity and great sensitivity, and can on occasion provide results which would not be attainable by other means. They are finding an increasing number and variety of applications not only in pure research, but in medicine and health, in many industries such as mining, textiles, metallurgy and the oil industry, and in some other fields such as archaeology and criminology. These matters were discussed at an IAEA symposium at Salzburg, 19 - 23 October 1964, in which 278 participants joined, from 28 countries and five international organizations. Most of the emphasis at the conference was on radioactivation analysis, which occupied six out of the nine sessions. Under this method, the material to be studied is exposed to neutrons or charged particles, or electromagnetic radiation such as X-rays. This causes nuclear transformations in the material, followed by radioactive decay. Each element forms nuclides which emit radiation of characteristic energy and half-life, by which the element can be identified and measured. Sessions were devoted to various applications, using as the source of radiation nuclear reactors, accelerators, and radioisotope sources; experimental techniques and the application of computers to activation analysis were also considered. Two sessions were devoted to the use of radioactive tracers in analysis, and one to the use of radioactive sources for elementary analysis by observing how radiation is absorbed and scattered, or how, when a sample is exposed to radiation, it emits secondary radiation

  10. 33 CFR 72.01-5 - Local Notice to Mariners.

    Science.gov (United States)

    2010-07-01

    ... Mariners free of charge on the Internet from the Coast Guard Navigation Center's Web site (http://www... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Local Notice to Mariners. 72.01-5 Section 72.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS...

  11. Using microorganisms to aid in hydrocarbon degradation

    International Nuclear Information System (INIS)

    Aliphatic hydrocarbons are threatening the potable water supply and the aquatic ecosystem. Given the right microbial inhabitant(s), a large portion of these aliphatic hydrocarbons could be biodegraded before reaching the water supply. The authors' purpose is to isolate possible oil-degrading organisms. Soil samples were taken from hydrocarbon-laden soils at petroleum terminals, a petroleum refinery waste-treatment facility, a sewage-treatment plant grease collector, a site of previous bioremediation, and various other places. Some isolates known to be good degraders were obtained from culture collection services. These samples were plated on a 10w-30 multigrade motor oil solid medium to screen for aliphatic hydrocarbon degraders. The degrading organisms were isolated, identified, and tested (CO2 evolution, BOD, and COD) to determine the most efficient degrader(s). Thirty-seven organisms were tested, and the most efficient degraders were Serratia marcescens, Escherichia coli, and Enterobacter agglomerans

  12. Using microorganisms to aid in hydrocarbon degradation

    Energy Technology Data Exchange (ETDEWEB)

    Black, W.; Zamora, J. (Middle Tennessee State Univ., Murfreesboro (United States))

    1993-04-01

    Aliphatic hydrocarbons are threatening the potable water supply and the aquatic ecosystem. Given the right microbial inhabitant(s), a large portion of these aliphatic hydrocarbons could be biodegraded before reaching the water supply. The authors' purpose is to isolate possible oil-degrading organisms. Soil samples were taken from hydrocarbon-laden soils at petroleum terminals, a petroleum refinery waste-treatment facility, a sewage-treatment plant grease collector, a site of previous bioremediation, and various other places. Some isolates known to be good degraders were obtained from culture collection services. These samples were plated on a 10w-30 multigrade motor oil solid medium to screen for aliphatic hydrocarbon degraders. The degrading organisms were isolated, identified, and tested (CO[sub 2] evolution, BOD, and COD) to determine the most efficient degrader(s). Thirty-seven organisms were tested, and the most efficient degraders were Serratia marcescens, Escherichia coli, and Enterobacter agglomerans.

  13. U.S. to aid coastal research

    Science.gov (United States)

    Katsouros, Mary Hope

    Prior to the 1964 implementation of the 1958 Convention on the Continental Shelf, oceanographers were free to plan and carry out research projects virtually anywhere on or under the seas of the world (see Article 5(1) and 5(8)). Today, dozens of coastal nations regulate marine research within 200 nautical miles (370 km) of their shores, imposing increasingly severe restrictions and creating diverse and uncertain consent procedures. Both the Reagan administration and Congress have acted recently to alleviate some of these jurisdictional problems being experienced by U.S. marine scientists.On March 10, 1983, President Reagan issued a proclamation on the “Exclusive Economic Zone of the United States of America” and related statements. It is the accompanying “Statement by the President” and the “Fact Sheet” on “United States Oceans Policy” (all three of which are dated March 10), rather than the proclamation, that outline the U.S. position on the conduct of marine scientific research. The “Statement by the President” declares that, While international law provides for a right of jurisdiction over marine scientific research within such a zone, the proclamation does not assert this right. I have elected not to do so because of the United States' interest in encouraging marine scientific research and avoiding any unnecessary burdens. The United States will nevertheless recognize the right of other coastal states to exercise jurisdiction over marine scientific research within 200 nautical miles of their coasts, if that jurisdiction is exercised reasonably in a manner consistent with international law. The “Fact Sheet” states that, The President has decided not to assert jurisdiction over marine scientific research in the United States EEZ [Exclusive Economic Zone]. This is consistent with U.S. interest in promoting maximum freedom for such research. The Department of State will take steps to facilitate access by U.S. scientists to foreign EEZ

  14. Modelling as an aid to nutrition research

    International Nuclear Information System (INIS)

    In many areas of research, including nutrition, the straightforward questions have now been answered and the speed of future progress will depend on successful collaboration between disciplines. Such collaboration is sometimes difficult, but can be helped by the adoption of a structured approach, such as that used in the development of mathematical models. Two examples of the use of mathematical modelling as a research tool in ruminant nutrition are considered. The first is the interface between the production of end products of digestion and their metabolism by the tissues. Absorbed nutrients undergo significant transformation by metabolism both during absorption across the gut wall and in the liver, and consideration of the published data suggests that metabolism by the visceral tissues needs to be considered separately from metabolism in the peripheral tissues. The lack of appropriate data to parametrize models stimulated a research programme on gut and liver metabolism. The second example relates to the control of intake and illustrates how the requirement for data to parametrize an intake model has identified the need to measure the daily patterns of voluntary intake, rumen volume and motility and concentrations of metabolites both in the rumen and entering the portal blood. (author). 18 refs, 4 figs, 3 tabs

  15. Analyzing Slogans To Aid Student School Achievement.

    Science.gov (United States)

    Ediger, Marlow

    Slogans are commonly used to advocate a point or view or a political stance. In education many slogans are used. One of these is the phrase "research shows that..." Many issues must be considered in interpreting research results, and the statement must be considered carefully. "Cooperative learning" is a slogan often advanced, but teachers must…

  16. Infrared thermographic diagnostic aid to aircraft maintenance

    Science.gov (United States)

    Delo, Michael; Delo, Steve

    2007-04-01

    Thermographic data can be used as a supplement to aircraft maintenance operations in both back shop and flight line situations. Aircraft systems such as electrical, propulsion, environmental, pitot static and hydraulic/pneumatic fluid, can be inspected using a thermal infrared (IR) imager. Aircraft systems utilize electro-hydraulic, electro-mechanical, and electro-pneumatic mechanisms, which, if accessible, can be diagnosed for faults using infrared technology. Since thermographs are images of heat, rather than light, the measurement principle is based on the fact that any physical object (radiating energy at infrared wavelengths within the IR portion of the electro-magnetic spectrum), can be imaged with infrared imaging equipment. All aircraft systems being tested with infrared are required to be energized for troubleshooting, so that valuable baseline data from fully operational aircraft can be collected, archived and referenced for future comparisons.

  17. Ergonomics: an aid to system design

    International Nuclear Information System (INIS)

    In recent years, the engineering community has recognized that ergonomics can make significant contributions to system design. Working together engineers and ergonomists can create designs that effectively meet system goals. By considering the role of humans and technology in the context of systems and by reducing the potential for errors, gains can be made in overall system reliability. Such efforts can reduce the need for costly backfits and increase system efficiency. (author)

  18. Issues of Aid to Nonpublic Schools. Volume IV: Appendices.

    Science.gov (United States)

    Erickson, Donald A.; Madaus, George F.

    This document reports on the role of the Federal Government in rendering financial aid to non-public schools. This report includes facts and attitudes. A two-fold approach toward gaining attitudinal data was undertaken. A critical review of existing attitudinal data was commissioned and an analysis of the attitudinal data gathered as part of…

  19. What Is the Aggregate Economic Rate of Return to Foreign Aid?

    DEFF Research Database (Denmark)

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    2015-01-01

    return to aid. Our results highlight the long run nature of aid-financed investments and the importance of channels other than accumulation of physical capital. We find the return to aid lies in ranges commonly accepted for public investments and there is little to justify the view that aid has had a...

  20. New patterns in health sector aid to India.

    Science.gov (United States)

    Jeffery, R

    1986-01-01

    Criticisms of health aid have largely been derived from African and Latin American experiences. It is suggested that such analyses, while valuable, cannot be applied wholesale to India without detailed examination of the patterns of health sector aid which have actually characterized the period since 1947. This article brings together material on the scale and form that this assistance has taken, and demonstrates that its focus has been preventive in emphasis and oriented towards the primary care sector. In some periods it has contributed a substantial share of total public sector expenditures, and in some spheres, it has played a major role, particularly the control of communicable diseases. However, the impact of less substantial sums going to prestige medical colleges or to population control programs should not be ignored; and several of the aid categories have been of dubious origin (PL-480 counterpart funds and U.S. food surpluses as the prime examples). However, the "new" health aid programs do not deserve the ready dismissal they have received in some quarters. PMID:3957509

  1. A microfluidic device for 2D to 3D and 3D to 3D cell navigation

    Science.gov (United States)

    Shamloo, Amir; Amirifar, Leyla

    2016-01-01

    Microfluidic devices have received wide attention and shown great potential in the field of tissue engineering and regenerative medicine. Investigating cell response to various stimulations is much more accurate and comprehensive with the aid of microfluidic devices. In this study, we introduced a microfluidic device by which the matrix density as a mechanical property and the concentration profile of a biochemical factor as a chemical property could be altered. Our microfluidic device has a cell tank and a cell culture chamber to mimic both 2D to 3D and 3D to 3D migration of three types of cells. Fluid shear stress is negligible on the cells and a stable concentration gradient can be obtained by diffusion. The device was designed by a numerical simulation so that the uniformity of the concentration gradients throughout the cell culture chamber was obtained. Adult neural cells were cultured within this device and they showed different branching and axonal navigation phenotypes within varying nerve growth factor (NGF) concentration profiles. Neural stem cells were also cultured within varying collagen matrix densities while exposed to NGF concentrations and they experienced 3D to 3D collective migration. By generating vascular endothelial growth factor concentration gradients, adult human dermal microvascular endothelial cells also migrated in a 2D to 3D manner and formed a stable lumen within a specific collagen matrix density. It was observed that a minimum absolute concentration and concentration gradient were required to stimulate migration of all types of the cells. This device has the advantage of changing multiple parameters simultaneously and is expected to have wide applicability in cell studies.

  2. A microfluidic device for 2D to 3D and 3D to 3D cell navigation

    International Nuclear Information System (INIS)

    Microfluidic devices have received wide attention and shown great potential in the field of tissue engineering and regenerative medicine. Investigating cell response to various stimulations is much more accurate and comprehensive with the aid of microfluidic devices. In this study, we introduced a microfluidic device by which the matrix density as a mechanical property and the concentration profile of a biochemical factor as a chemical property could be altered. Our microfluidic device has a cell tank and a cell culture chamber to mimic both 2D to 3D and 3D to 3D migration of three types of cells. Fluid shear stress is negligible on the cells and a stable concentration gradient can be obtained by diffusion. The device was designed by a numerical simulation so that the uniformity of the concentration gradients throughout the cell culture chamber was obtained. Adult neural cells were cultured within this device and they showed different branching and axonal navigation phenotypes within varying nerve growth factor (NGF) concentration profiles. Neural stem cells were also cultured within varying collagen matrix densities while exposed to NGF concentrations and they experienced 3D to 3D collective migration. By generating vascular endothelial growth factor concentration gradients, adult human dermal microvascular endothelial cells also migrated in a 2D to 3D manner and formed a stable lumen within a specific collagen matrix density. It was observed that a minimum absolute concentration and concentration gradient were required to stimulate migration of all types of the cells. This device has the advantage of changing multiple parameters simultaneously and is expected to have wide applicability in cell studies. (paper)

  3. Indoor wayfinding and navigation

    CERN Document Server

    2015-01-01

    Due to the widespread use of navigation systems for wayfinding and navigation in the outdoors, researchers have devoted their efforts in recent years to designing navigation systems that can be used indoors. This book is a comprehensive guide to designing and building indoor wayfinding and navigation systems. It covers all types of feasible sensors (for example, Wi-Fi, A-GPS), discussing the level of accuracy, the types of map data needed, the data sources, and the techniques for providing routes and directions within structures.

  4. Assessing business responses to HIV / AIDS in Kenya.

    Science.gov (United States)

    Roberts, M; Wangombe, J

    1995-01-01

    A consulting firm conducted interviews with managers of 16 businesses in 3 Kenyan cities, representatives of 2 trade unions, focus groups with workers at 13 companies, and an analysis of financial/labor data from 4 companies. It then did a needs assessment. The business types were light industry, manufacturing companies, tourism organizations, transport firms, agro-industrial and plantation businesses, and the service industry. Only one company followed all the workplace policy principles recommended by the World Health Organization and the International Labor Organization. Six businesses required all applicants and/or employees to undergo HIV testing. All their managers claimed that they would not discriminate against HIV-infected workers. Many workers thought that they would be fired if they were--or were suspected to be--HIV positive. Lack of a non-discrimination policy brings about worker mistrust of management. 11 companies had some type of HIV/AIDS education program. All the programs generated positive feedback. The main reasons for not providing HIV/AIDS education for the remaining 5 companies were: no employee requests, fears that it would be taboo, and assumptions that workers could receive adequate information elsewhere. More than 90% of all companies distributed condoms. 60% offered sexually transmitted disease diagnosis and treatment. About 33% offered counseling. Four companies provided volunteer HIV testing. Almost 50% of companies received financial or other external support for their programs. Most managers thought AIDS to be a problem mainly with manual staff and not with professional staff. Almost all businesses offered some medical benefits. The future impact of HIV/AIDS would be $90/employee/year (by 2005, $260) due to health care costs, absenteeism, retraining, and burial benefits. The annual costs of a comprehensive workplace HIV/AIDS prevention program varied from $18 to $54/worker at one company. PMID:12289839

  5. Responding to medical crises: AIDS treatment, responsibilisation and the logic of choice.

    Science.gov (United States)

    Beckmann, Nadine

    2013-01-01

    The framing of HIV/AIDS as a crisis has facilitated the rollout of large-scale intervention programmes that represent an enormous effort at mainstreaming biomedical rationalities and neoliberal notions of responsibilisation and self-care. Based on a 'logic of choice' (Mol 2008) and 'responsibilised citizenship' (Robins 2005a), although veiled in a language of rights and partnership, the heavy focus on individual behaviour and a pharmaceutical 'solution' to AIDS shifts the burden of responsibility for the success of the heavily funded programmes onto the shoulders of the patients and conceals alternative forms of responsibility. Analysing how HIV-positive people in Tanzania navigate life with HIV and the complex treatment regimens, this paper looks beyond biomedical rationality, which places the preservation of individual biological life at the centre of its logic, and analyses people's constant struggle to negotiate the meaning of 'responsible behaviour' in the context of their lived realities. This repositions the notion of responsibility in the realm of the social and reveals the rationality behind apparently irrational practices. PMID:23898836

  6. Teaching Basic First-Aid Skills against Home Accidents to Children with Autism through Video Modeling

    Science.gov (United States)

    Ergenekon, Yasemin

    2012-01-01

    It is known that children with DD can learn first-aid skills and use whenever needed. Applying first-aid skills was taught to three inclusion students with autism through "first-aid skills training package". In the study multiple probe design with probe trials across behaviors was used. The findings indicated that first-aid skills training package…

  7. Navigation in diagnosis and therapy

    International Nuclear Information System (INIS)

    Image-guided navigation for surgery and other therapeutic interventions has grown in importance in recent years. During image-guided navigation a target is detected, localized and characterized for diagnosis and therapy. Thus, images are used to select, plan, guide and evaluate therapy, thereby reducing invasiveness and improving outcomes. A shift from traditional open surgery to less-invasive image-guided surgery will continue to impact the surgical marketplace. Increases in the speed and capacity of computers and computer networks have enabled image-guided interventions. Key elements in image navigation systems are pre-operative 3D imaging (or real-time image acquisition), a graphical display and interactive input devices, such as surgical instruments with light emitting diodes (LEDs). CT and MRI, 3D imaging devices, are commonplace today and 3D images are useful in complex interventions such as radiation oncology and surgery. For example, integrated surgical imaging workstations can be used for frameless stereotaxy during neurosurgical interventions. In addition, imaging systems are being expanded to include decision aids in diagnosis and treatment. Electronic atlases, such as Voxel Man or others derived from the Visible Human Project, combine a set of image data with non-image knowledge such as anatomic labels. Robot assistants and magnetic guidance technology are being developed for minimally invasive surgery and other therapeutic interventions. Major progress is expected at the interface between the disciplines of radiology and surgery where imaging, intervention and informatics converge

  8. Humanoid Robot Navigation Based on Groping Locomotion Algorithm to Avoid an Obstacle

    OpenAIRE

    Yussof, Hanafiah; Yamano, Mitsuhiro; Nasu, Yasuo; Ohka, Masahiro

    2006-01-01

    The development of autonomous navigation system for humanoid robot to solve the problem of "working coexistence" of humans and robots is an important issue. It is apparent that the common living and working environment to be shared by humanoid robots is presently adapted mainly to human, and it cannot be expected that this will be significantly changed to suit the needs of robots. Hence, the problem of human-humanoid robot interaction, and humanoid robot-surrounding environment interaction ar...

  9. COMPUTATION OF RETURN FLOWS DUE TO NAVIGATION TRAFFICS IN RESTRICTED WATERWAYS

    Institute of Scientific and Technical Information of China (English)

    B.S.MAZUMDER; S.K.DAS; S.N.DAS

    2006-01-01

    The paper deals with the development of an empirical model to compute the return flow due to the movement of navigation traffics in restricted waterway when the speed of the navigation traffic is under sub-critical range. The velocity profile of the return flow is modelled, where the functional dependence with respect to ambient flow, principal dimensions of the vessel, wetted cross-sectional area of the river, width and average depth of the river, and the lateral distance of the vessel from the bank are implicitly considered. This model has been validated with the observed data collected from the four specific sites, such as Kampsville, Apple River Island, Goose Island and Clarks Ferry of Illinois River during barge-tow movement. The present model shows significant improvement of return flow prediction in comparison to earlier empirical results. This model has also the ability to determine the locus of zero velocity point.

  10. Navigating the massive world of reddit: Using backbone networks to map user interests in social media

    OpenAIRE

    Olson, Randal S.; Neal, Zachary P.

    2013-01-01

    In the massive online worlds of social media, users frequently rely on organizing themselves around specific topics of interest to find and engage with like-minded people. However, navigating these massive worlds and finding topics of specific interest often proves difficult because the worlds are mostly organized haphazardly, leaving users to find relevant interests by word of mouth or using a basic search feature. Here, we report on a method using the backbone of a network to create a map o...

  11. From self-assessment to frustration, a small step toward autonomy in robotic navigation

    OpenAIRE

    Adrien eJauffret; Nicolas eCuperlier; Philippe eGaussier; Philippe eTarroux

    2013-01-01

    Autonomy and self-improvement capabilities are still challenging in the fields of robotics and machine learning. Allowing a robot to autonomously navigate in wide and unknown environments not only requires a repertoire of robust strategies to cope with miscellaneous situations, but also needs mechanisms of self-assessment for guiding learning and for monitoring strategies. Monitoring strategies requires feedbacks on the behavior's quality, from a given fitness system in order to take correct ...

  12. Road network modeling in open source GIS to manage the navigation of autonomous robots

    Science.gov (United States)

    Mangiameli, Michele; Muscato, Giovanni; Mussumeci, Giuseppe

    2013-10-01

    The autonomous navigation of a robot can be accomplished through the assignment of a sequence of waypoints previously identified in the territory to be explored. In general, the starting point is a vector graph of the network consisting of possible paths. The vector graph can be directly available in the case of actual road networks, or it can be modeled, i.e. on the basis of cartographic supports or, even better, of a digital terrain model (DTM). In this paper we present software procedures developed in Grass-GIS, PostGIS and QGIS environments to identify, model, and visualize a road graph and to extract and normalize sequence of waypoints which can be transferred to a robot for its autonomous navigation.

  13. Indoor Navigation to Support the Blind Person Using True Pathway within the Map

    Directory of Open Access Journals (Sweden)

    Abbas M. Ali

    2010-01-01

    Full Text Available Problem statement: Map creation remains a very active field in the robotics and AI community, however it contains some challenge points like data association and the high degree of accuracy of localization which are seems to be difficult in some cases, more than that, most of these study focus on the robot navigation, without any consideration for the semantic of the environment, to serve human like blind persons. Approach: This study introduced a monocular SLAM method, which uses the Scale Invariant Features Transform (SIFT representation for the scene. The scene represented as clouds of sift features within the map; this hierarchical representation of space, serving to estimate the current direction in the environment within the current session. The system exploited the tracking of the same features of successive frames to calculate scalar weights for these features, to build a map of the environment indicating the camera movement, then by comparing the camera movement of the current moving with the true pathway within the same session the system can help and advice the blind person to navigate more confidently, through auditory information for the path way in the surroundings. Extended Kalman Filter (EKF used to estimate the camera movement within the successive frames. Results: The experimental work tested using the proposed method with a hand-held camera walking in indoor environment. The results show a good estimation on the spatial locations of the camera within few milliseconds. Tracking of the true pathway in addition to semantic environment within the session can give a good support to the blind person for navigation. Conclusion: The study presented new semantic features model helping the blind person for navigation environment using these clouds of features, for long-term appearance-based localization of a cane with web camera vision as the external sensor.

  14. Strange Bedfellows: The Catholic Church and Brazilian National AIDS Program in the Response to HIV/AIDS in Brazil

    OpenAIRE

    Murray, Laura R.; Garcia, Jonathan; Muñoz-Laboy, Miguel; Parker, Richard G.

    2011-01-01

    The HIV epidemic has raised important tensions in the relationship between Church and State in many parts of Latin America where government policies frequently negotiate secularity with religious belief and doctrine. Brazil represents a unique country in the region due to the presence of a national religious response to HIV/AIDS articulated through the formal structures of the Catholic Church. As part of an institutional ethnography on religion and HIV/AIDS in Brazil, we conducted an extended...

  15. Designing non-speech sounds to support navigation in mobile phone menus

    OpenAIRE

    Leplatre, G.; Brewster, S.A.

    2000-01-01

    This paper describes a framework for integrating non-speech audio to hierarchical menu structures where the visual feedback is limited. In the first part of this paper, emphasis is put on how to extract sound design principles from actual navigation problems. These design principles are then applied in the second part, through the design, implementation and evaluation of a set of sounds in a computer-based simulation of the Nokia 6110 mobile phone. The evaluation indicates that non-speech sou...

  16. Both visual and idiothetic cues contribute to head direction cell stability during navigation along complex routes

    OpenAIRE

    Yoder, Ryan M.; Clark, Benjamin J.; Brown, Joel E.; Lamia, Mignon V.; Valerio, Stephane; Shinder, Michael E.; Taube, Jeffrey S.

    2011-01-01

    Successful navigation requires a constantly updated neural representation of directional heading, which is conveyed by head direction (HD) cells. The HD signal is predominantly controlled by visual landmarks, but when familiar landmarks are unavailable, self-motion cues are able to control the HD signal via path integration. Previous studies of the relationship between HD cell activity and path integration have been limited to two or more arenas located in the same room, a drawback for interp...

  17. 33 CFR 149.560 - How must buoys used to define traffic lanes be marked and lighted?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false How must buoys used to define traffic lanes be marked and lighted? 149.560 Section 149.560 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: DESIGN, CONSTRUCTION, AND EQUIPMENT Aids to Navigation Lights on...

  18. Tools to aid the management of contaminated inhabited areas

    International Nuclear Information System (INIS)

    The complex situation posed by nuclear or radiological accidents in inhabited environments required to carefully analyze the different management options to reduce pollution in different areas. in addition to radiological factors taken into account other factors such as cost, the doses received by workers, environmental impact, waste management ... and necessarily must have mechanisms of interaction with stake holders. For all this, in the EURANOS European project they have developed tools to aid the recovery phase. (Author)

  19. Strengthening families to support children affected by HIV and AIDS.

    Science.gov (United States)

    Richter, Linda M; Sherr, Lorraine; Adato, Michele; Belsey, Mark; Chandan, Upjeet; Desmond, Chris; Drimie, Scott; Haour-Knipe, Mary; Hosegood, Victoria; Kimou, Jose; Madhavan, Sangeetha; Mathambo, Vuyiswa; Wakhweya, Angela

    2009-01-01

    This paper provides an overview of the arguments for the central role of families, defined very broadly, and we emphasise the importance of efforts to strengthen families to support children affected by HIV and AIDS. We draw on work conducted in the Joint Learning Initiative on Children and AIDS's Learning Group 1: Strengthening Families, as well as published data and empirical literature to provide the rationale for family strengthening. We close with the following recommendations for strengthening families to ameliorate the effects of HIV and AIDS on children. Firstly, a developmental approach to poverty is an essential feature of responses to protect children affected by HIV and AIDS, necessary to safeguard their human capital. For this reason, access to essential services, such as health and education, as well as basic income security, must be at the heart of national strategic approaches. Secondly, we need to ensure that support garnered for children is directed to families. Unless we adopt a family oriented approach, we will not be in a position to interrupt the cycle of infection, provide treatment to all who need it and enable affected individuals to be cared for by those who love and feel responsible for them. Thirdly, income transfers, in a variety of forms, are desperately needed and positively indicated by available research. Basic economic security will relieve the worst distress experienced by families and enable them to continue to invest in the health care and education of their children. Lastly, interventions are needed to support distressed families and prevent knock-on negative outcomes through programmes such as home visiting, and protection and enhancement of children's potential through early child development efforts. PMID:22380973

  20. Representing WWW navigational data: a graphical methodology to support qualitative analysis

    OpenAIRE

    Honey Lucas

    1999-01-01

    This paper concerns the development and use of a graphical methodology in the analysis of individuals World Wide Web navigational behaviour. Specifically, it reports on the comparison of this methodology to other methodologies of qualitative analysis. Examples are given of the graphical representations of individuals interactions with particular World Wide Web medical resources, and the integration of these graphical representations with textual data considered. Indications for further develo...

  1. Representing WWW navigational data: a graphical methodology to support qualitative analysis

    Directory of Open Access Journals (Sweden)

    Honey Lucas

    1999-01-01

    Full Text Available This paper concerns the development and use of a graphical methodology in the analysis of individuals’ World Wide Web navigational behaviour. Specifically, it reports on the comparison of this methodology to other methodologies of qualitative analysis. Examples are given of the graphical representations of individuals’ interactions with particular World Wide Web medical resources, and the integration of these graphical representations with textual data considered. Indications for further development in this area are also suggested.

  2. Navigation by green turtles: which strategy do displaced adults use to find Ascension Island?

    OpenAIRE

    Åkesson, Susanne; Broderick, A. C.; Glen, F.; Godley, B. J.; Luschi, P; Papi, F; Hays, G.C.

    2003-01-01

    Sea turtles are known to perform long-distance, oceanic migrations between disparate feeding areas and breeding sites, some of them located on isolated oceanic islands. These migrations demonstrate impressive navigational abilities, but the sensory mechanisms used are still largely unknown. Green turtles breeding at Ascension Island perform long oceanic migrations (>2200 km) between foraging areas along the Brazilian coast and the isolated island. By performing displacement experiments of ...

  3. Navigating between the Religious and the Secular: Responding to the Muslim `Woman Question' in Diasporic Britain

    OpenAIRE

    Uddin, Sabah Firoz

    2013-01-01

    This study is a story of the multiple sides of subject formation, the ways in which immigrant practice, cultural and religious, and the norms of British civil society operate in relation, each responding to the other. In this work I challenge generalized third-person notions of Muslim women as sites of oppression, and place British Muslim women at the center of their own stories. I investigate how South Asian Muslim women in Britain navigate between competing religio-cultural and secular disc...

  4. An Effective Approach to Improving Low-Cost GPS Positioning Accuracy in Real-Time Navigation

    OpenAIRE

    Md. Rashedul Islam; Jong-Myon Kim

    2014-01-01

    Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previous...

  5. SLAM algorithm applied to robotics assistance for navigation in unknown environments

    OpenAIRE

    Lobo Pereira Fernando; di Sciascio Fernando A; Soria Carlos M; Lopez Natalia; Auat Cheein Fernando A; Carelli Ricardo

    2010-01-01

    Abstract Background The combination of robotic tools with assistance technology determines a slightly explored area of applications and advantages for disability or elder people in their daily tasks. Autonomous motorized wheelchair navigation inside an environment, behaviour based control of orthopaedic arms or user's preference learning from a friendly interface are some examples of this new field. In this paper, a Simultaneous Localization and Mapping (SLAM) algorithm is implemented to allo...

  6. Redistribution to Rent Seekers, Foreign Aid and Economic Growth

    OpenAIRE

    Roland Hodler

    2004-01-01

    This paper analyzes the consequences of redistribution of public funds to rent seekers. Therefore, it introduces redistribution to rent seeking agents into Barro's (1990) endogenous growth model with a productive public sector. It shows that the growth rate decreases in the share of the public funds that is redistributed. The public sector's relative sizes that maximize growth and welfare become also smaller in presence of redistribution. Further, if foreign aid is added to the model, the rel...

  7. Complementary terrain/single beacon-based AUV navigation

    Digital Repository Service at National Institute of Oceanography (India)

    Maurya, P.; Curado, T.F.; António, P.

    This paper describes work done towards the development of advanced geophysical-based navigation systems for autonomous underwater vehicles (AUVs). The specific problem that we tackle is that of combining terrain-aided navigation (TAN) with single...

  8. "AIDS is rape!" gender and sexuality in children's responses to HIV and AIDS.

    Science.gov (United States)

    Bhana, Deevia

    2009-08-01

    This paper examines young African school children's understanding of HIV and AIDS. Based on focus group interviews with children aged 7-8 in KwaZulu-Natal province, South Africa, it explores the ways in which gender and sexuality feature in their responses to the disease. Data were collected between 2003 and 2004 through 26 focus groups involving 55 boys and 64 girls. The paper argues that younger children are active agents in giving meaning to the disease. Their agency is negotiated within complex social processes involving sexual violence, highly unequal gender/age inequalities, but also sexual expression. Those expressions are subsumed however under a regime of violence and fear catapulting men, albeit with contestation, as chief vectors in the spread of the disease and a source of girls' anxieties. Children's responses to the disease are the effects of material, symbolic and discursive forces effectively constraining the opportunities available to them and creating patterns of vulnerability especially for young girls. Interventions aimed at scaling up efforts to address young children responses to the disease must be situated in parallel efforts to end poverty, sexual violence and pervasive gender inequalities in order to foster more comprehensively the exercise of young children's agency. PMID:19560247

  9. 78 FR 32412 - Navigation Safety Advisory Council; Vacancies

    Science.gov (United States)

    2013-05-30

    ..., marital status, disability and generic information, age, membership in an employee organization, or other... and equipment, routing measures, marine information, diving safety, and aids to navigation systems...@uscg.mil FOR FURTHER INFORMATION CONTACT: Mr. Mike Sollosi, the NAVSAC Alternate Designated...

  10. 77 FR 15784 - Navigation Safety Advisory Council; Vacancies

    Science.gov (United States)

    2012-03-16

    ..., disability and generic information, age, membership in an employee organization, or other non-merit factor... and equipment, routing measures, marine information, diving safety, and aids to navigation systems....gov . Members of the public should not submit personal information into a docket, as it becomes...

  11. Hearing Aids

    Science.gov (United States)

    ... electrical nerve impulses and send them to the auditory nerve, which connects the inner ear to the ... prefer. Cleaning makes a difference in hearing aid comfort. A perfectly comfortable hearing aid can become pretty ...

  12. Storyboarding used as an aid to explore grief.

    Science.gov (United States)

    2016-07-01

    Yvonne Dexter, writing in Nursing Children and Young People, discusses the use of storyboarding and its use as a reflective practice aid. As children's nurses are among the child health professionals most directly affected by childhood death, storyboarding can provide nursing students with a safe environment to reflect on their feelings about the death of a child. Ms Dexter considers the potential for its use in practice, for example in clinical supervision and classroom settings, to manage grief. PMID:27380710

  13. CD4 count and viral load specific rates of AIDS, non-AIDS and deaths according to current antiretroviral use

    Directory of Open Access Journals (Sweden)

    A Mocroft

    2012-11-01

    Full Text Available Background CD4 and viral loads are used in clinical trials as surrogate endpoints for assessing efficacy of newly available antiretrovirals. If antiretrovirals act through other pathways or negatively affect the risk of disease this would not be identified prior to licensing. The aims of this study were to investigate the CD4 and viral load specific rates of fatal and non-fatal AIDS and non-AIDS events according to current antiretrovirals. Methods Poisson regression was used to compare overall events (fatal or non-fatal AIDS, non-AIDS or death, AIDS events (fatal and non-fatal or non-AIDS events (fatal or non-fatal for specific nucleoside pairs and third drugs used with>1000 person-years of follow-up (PYFU after January 1st 2001. Results 9801 patients were included. The median baseline date was January 2004 (interquartile range [IQR] January 2001–February 2007, age was 40.4 (IQR 34.6–47.3 years, and time since starting cART was 3.3 (IQR 0.9–5.1 years. At baseline, the median nadir CD4 was 162 (IQR 71–257/mm3, baseline CD4 was 390 (IQR 249–571/mm3, viral load was 1.9 (IQR 1.7–3.3 log10copies/ml and 2961 (30.2% had a prior AIDS diagnosis and 6.4 years prior to baseline. During 42372.5 PYFU, 1203 (437 AIDS and 766 non-AIDS events occurred. The overall event rate was 2.8 per 100 PYFU (95% confidence interval [CI] 2.7–3.0, of AIDS events was 1.0 (95% CI 0.9–1.1 and of non-AIDS events was 1.8 (95% CI 1.7–1.9. Of the AIDS events, 53 (12.1%were fatal as were 239 (31.2% of the non-AIDS events. After adjustment, there was weak evidence of a difference in the overall events rates between nucleoside pairs (global p-value=0.084, and third drugs (global p-value=0.031. Compared to zidovudine/lamivudine, patients taking abacavir/lamivudine (adjusted incidence rate ratio [aIRR] 1.22; 95% CI 0.99–1.49 and abacavir plus one other nucleoside (aIRR 1.51; 95% CI 1.14–2.02 had an increased incidence of overall events. Comparing the third drugs

  14. HIV Prevention: The Key to Ending AIDS by 2030

    Science.gov (United States)

    Poku, Nana K.

    2016-01-01

    There is no viable substitute for re-energizing, funding and supporting culturally attuned, locally staffed HIV advocacy and prevention programmes, especially in resource poor settings. The evidence that such interventions are effective remains compelling; and although the cost implications are not negligible, the medium to long-term outcomes must be regarded not as complementary, but as integral, to biomedical interventions. The success of the anti-retroviral drugs upscale has enabled a noticeable improvement in AIDS related morbidity and mortality in the recent years; yet the underlying dynamics of the epidemic remains undetermined by the rate at which new infections are taking place in relation to the number of AIDS deaths. While the rate of new HIV infections is stabilising in some of the hardest hit countries, it remains far too high and the future cost of maintaining an ever-expanding pool of people reliant on daily drugs for survival is unsustainable. Countries must exercise caution in continuing to focus on treatment as a ‘quick fix’ to end AIDS as a public health concern. HIV is a socially culturally induced crisis and, as such, a variety of measures are needed simultaneously to appeal to different people, groups and circumstances. PMID:27347272

  15. Ecodesign Navigator

    DEFF Research Database (Denmark)

    Simon, M; Evans, S.; McAloone, Timothy Charles; Sweatman, A.; Bhamra, T.; Poole, S.

    The Ecodesign Navigator is the product of a three-year research project called DEEDS - DEsign for Environment Decision Support. The initial partners were Manchester Metropolitan University, Cranfield University, Engineering 6 Physical Sciences Resaech Council, Electrolux, ICL, and the Industry...

  16. AIDS and journalism. Trying to tell too clear a story.

    Science.gov (United States)

    Cohen, J

    1994-12-01

    Much in science is complex. Scientists, by definition, work within the realm of complex hypothesis, empirical evidence, and proof. Questions, answers, details, complexities; that is the domain of the scientist. Journalists, on the other hand, are paid to develop and present stories which are clearly read and interpreted by the general public. The mechanics and dynamics of HIV and AIDS are among the most complex scientific challenges in the history of humankind. Journalists calling upon scientists to obtain and report clear, concise, information about the agent and its resulting pandemic are therefore surely not always going to receive simple, readily reportable responses. HIV is a moving target upon which research continues. While there are some definitively affirmative and some definitively negative factors about HIV, the gray areas and speculation remain vast. The author gives a few examples of AIDS stories which the media mishandled because they were trying to tell too clear a story. He then discusses stories flawed because scientists managed to present clear information about which journalists were overly skeptical. In one case, the public was informed that AIDS vaccines were not working, with headlines which insinuated that the vaccines themselves were causing infections. None of the vaccines, however, contained infectious materials. As a result, people became overly fearful of participating in HIV vaccine trials. Coverage of the potential identification of HIV-3 was premature and only scared people, while Rolling Stone magazine's article hypothesizing the origin of HIV via trials of a contaminated polio vaccine in the Belgium Congo in the late 1950s should not have been published. Clear answers about HIV/AIDS are few and far between, but interesting and significant stories can still be found; they are just hard to tell. PMID:12319130

  17. US Foreign Policy and Aid to the Peace Corps

    Directory of Open Access Journals (Sweden)

    Donald D.A. Schaefer

    2009-01-01

    Full Text Available Problem statement: This study examined foreign aid as administered by the US Agency for International Development (USAID through four presidencies, beginning with the Reagan era. Aid dispensed to the Peace Corps for humanitarian purposes was the major focus of the investigation. The research proposed that such aid should continue under the President Barack Obama administration. Approach: The approach taken used both qualitative analyses of the four administrations along with quantitative analyses of the data from USAID. Results: The findings indicated that, while many forms of economic and military assistance had been both used and abused throughout much of American history, the Peace Corps created under President John F. Kennedy presented an exception. However, the Peace Corps had received both benefit and harm as a beneficiary of US foreign aid due to fluctuating economic realities associated with the federal budget. President Reagan was a strong supporter of the Peace Corps; yet, it was “under his watch” that the Gramm-Rudman-Hollings Deficit Reduction Act of 1985 was passed, which negatively influenced nearly all forms of economic and military assistance distributed through USAID. Starting with President Clinton’s second term funding for USAID dramatically increased. Conclusion: The Peace Corps was not immune to the adverse effects, but funding also increased under President Clinton. From this time onward, the Peace Corps has enjoyed a high level of political and financial support, a scenario that deserves to be continued under President Obama. This study can help future analyses of the US presidential responses to the giving of assistance to the Peace Corps.

  18. Silver impregnation in situ: an aid to radiographic interpretation

    International Nuclear Information System (INIS)

    In evaluating radiographs of the limb joints and head, students encounter difficulty where superimposition occurs. By replacing calcium with silver salts in the bone, enhanced radiopacity can be produced. In this study, silver impregnation was used to increase the radiopacity of individual carpal and tarsal bones, selected bones of the skull and the sinuses, and guttural pouch of the horse. This provides an interpretation aid for teaching radiographic anatomy of these regions

  19. XVII International AIDS Conference: From Evidence to Action - Regional focus

    OpenAIRE

    Baijal, Parijat; Kort, Rodney

    2009-01-01

    This article summarizes the challenges, opportunities and lessons learned from presentations, discussions and debates addressing major policy and programmatic responses to HIV in six geographical regions: Sub-Saharan Africa, Asia and the Pacific, Eastern Europe and Central Asia, Latin America, Caribbean, and Middle East and North Africa. It draws from AIDS 2008 Leadership and Community Programmes, particularly the six regional sessions, and Global Village activities. While the epidemiological...

  20. Putting Political Economy to Use in Aid Policies

    OpenAIRE

    Hout, Wil

    2015-01-01

    textabstractPolitical economy analysis has been a favourite instrument among donors of development aid since roughly the turn of the century. Donors have emphasised the usefulness of such forms of analysis because they realised that their focus on the formal aspects of the social and political organisation of countries had caused them to overlook important elements of the “political economy” of these countries. As a result, political and governance reform programmes, which had become part and...

  1. A Representation of Uncertainty to Aid Insight into Decision Models

    OpenAIRE

    Jimison, Holly B.

    2013-01-01

    Many real world models can be characterized as weak, meaning that there is significant uncertainty in both the data input and inferences. This lack of determinism makes it especially difficult for users of computer decision aids to understand and have confidence in the models. This paper presents a representation for uncertainty and utilities that serves as a framework for graphical summary and computer-generated explanation of decision models. The application described that tests the methodo...

  2. Road navigation using multiple dissimilar environmental features to bridge GNSS outages

    OpenAIRE

    Walter, D; Groves, P. D.; Mason, B.; Harrison, J.(School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom); Woodward, J.; Wright, P

    2015-01-01

    Many navigation techniques have now become so reliant on GNSS that there is no back-up when there is limited or no signal reception. If there is interference, deliberate jamming or spoofing, and/or blockage and reflection of the signals by buildings, navigation could be lost or become misleading. Other navigation techniques harness different technologies such as Wi-Fi, eLoran and inertial navigation. However, each of these techniques has its own limitations, such as coverage, degradation in u...

  3. Navigation Using Inertial Sensors

    OpenAIRE

    Groves, P. D.

    2015-01-01

    This tutorial provides an introduction to navigation using inertial sensors, explaining the underlying principles. Topics covered include accelerometer and gyro technology and their characteristics, strapdown inertial navigation, attitude determination, integration and alignment, zero updates, motion constraints, pedestrian dead reckoning using step detection, and fault detection.

  4. United Nations system efforts to support the response to AIDS in China

    Institute of Scientific and Technical Information of China (English)

    Jing; Lin; HE; Joel; REHNSTROM

    2005-01-01

    In the last two years, we have seen a remarkable intensification in the response to AIDS in China. A number of organizations have joined and contributed to the efforts of the Chinese government in responding the AIDS epidemic in China. This article specifically describes the role of the United Nations in supporting and strengthening those responses.Achievements of the United Nations (UN) highlighted in the article include: strengthened leadership and political commitment to respond to AIDS; improved HIV/AIDS surveillance and information; expanded prevention efforts; improved treatment, care and support to people living with HIV and increased resources for AIDS programs. Additional roles of e., one national plan on AIDS; one national coordinating authority for AIDS; and one monitoring and evaluation system for AIDS. In addition, the UN system is expected to strengthen alignment and harmonization of activities of all international organizations and improved accountability and oversight. Remaining challenges identified include increasing awareness of AIDS and reducing stigma and discrimination; reducing vulnerability and risk behaviour among specific groups;providing improved treatment, care and support for people living with HIV; promoting stronger engagement by civil society, and; addressing the gender dimensions of AIDS.

  5. Foreign aid

    DEFF Research Database (Denmark)

    Tarp, Finn

    2008-01-01

    Foreign aid has evolved significantly since the Second World War in response to a dramatically changing global political and economic context. This article (a) reviews this process and associated trends in the volume and distribution of foreign aid; (b) reviews the goals, principles and instituti......Foreign aid has evolved significantly since the Second World War in response to a dramatically changing global political and economic context. This article (a) reviews this process and associated trends in the volume and distribution of foreign aid; (b) reviews the goals, principles and...... institutions of the aid system; and (c) discusses whether aid has been effective. While much of the original optimism about the impact of foreign aid needed modification, there is solid evidence that aid has indeed helped further growth and poverty reduction...

  6. Hotline in Egypt marks change in government attitude to AIDS.

    Science.gov (United States)

    1995-10-01

    The first 24-hour AIDS hotline in the Arab world will open in Cairo, Egypt, in October 1995. The opening of the new service marks a change in attitude on the part of the Egyptian government, which has maintained a discreet AIDS control program in the past. Approval from religious leaders was necessary for the new program to begin; the United Nations Children's Fund (UNICEF) played a prominent role in negotiations. The "Counsel and Hot Line Centre," which will be based in Imbala district, will employ 19 people, including two doctors and two psychologists. The Centre was funded with US$300,000 from the Ford Foundation. Currently, 478 persons with HIV infections and 110 people with AIDS have been reported. The ministry estimates that there are 5000-7000 persons with HIV infections in Egypt. Although these figures were greeted with suspicion by organizations outside of Egypt, subsequent testing has indicated low prevalence rates for this country, despite high tourism and a large population of migrant workers. PMID:12290451

  7. What Is the Aggregate Economic Rate of Return to Foreign Aid?

    DEFF Research Database (Denmark)

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    2015-01-01

    In recent years, academic studies have been converging towards the view that foreign aid promotes aggregate economic growth. We employ a simulation approach to: (i) validate the coherence of empirical aid-growth studies published since 2008; and (ii) calculate plausible ranges for the rate of...... return to aid. Our results highlight the long run nature of aid-financed investments and the importance of channels other than accumulation of physical capital. We find the return to aid lies in ranges commonly accepted for public investments and there is little to justify the view that aid has had a...

  8. Evaluation of navigation interfaces in virtual environments

    Science.gov (United States)

    Mestre, Daniel R.

    2014-02-01

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

  9. Patient Navigation Facilitates Medical and Social Services Engagement Among HIV-Infected Individuals Leaving Jail and Returning to the Community

    OpenAIRE

    Koester, Kimberly A; Morewitz, Mark; Pearson, Charles; Weeks, John; Packard, Rebecca; Estes, Milton; Tulsky, Jacqueline; Kang-Dufour, Mi_Suk; Myers, Janet J

    2014-01-01

    HIV-infected individuals leaving jails, facilities typically used to confine accused persons awaiting trial or to incarcerate persons for minor offenses, often face barriers to engagement with medical and social-support services. Patient navigation is a model that may ease these barriers by supporting individuals in negotiating fragmented and highly bureaucratic systems for services and care. While there is evidence linking navigation to a reduction in health disparities, little is known abou...

  10. [Computer-assisted navigation in orthognathic surgery. Application to Le Fort I osteotomy.

    Science.gov (United States)

    Benassarou, M; Benassarou, A; Meyer, C

    2013-08-01

    Computer-assisted navigation is a tool that allows the surgeon to reach intraoperatively a previously defined target. This technique can be applied to the positioning of bone fragments in orthognathic surgery. It is not used routinely yet because there are no specifically dedicated systems available on the market for this kind of surgery. The goal of our study was to describe the various systems that could be used in orthognathic surgery and to report our experience of computer-assisted surgery in the positioning of the maxilla during maxillomandibular osteotomies. PMID:23928252

  11. From self-assessment to frustration, a small step toward autonomy in robotic navigation.

    Science.gov (United States)

    Jauffret, Adrien; Cuperlier, Nicolas; Tarroux, Philippe; Gaussier, Philippe

    2013-01-01

    Autonomy and self-improvement capabilities are still challenging in the fields of robotics and machine learning. Allowing a robot to autonomously navigate in wide and unknown environments not only requires a repertoire of robust strategies to cope with miscellaneous situations, but also needs mechanisms of self-assessment for guiding learning and for monitoring strategies. Monitoring strategies requires feedbacks on the behavior's quality, from a given fitness system in order to take correct decisions. In this work, we focus on how a second-order controller can be used to (1) manage behaviors according to the situation and (2) seek for human interactions to improve skills. Following an incremental and constructivist approach, we present a generic neural architecture, based on an on-line novelty detection algorithm that may be able to self-evaluate any sensory-motor strategies. This architecture learns contingencies between sensations and actions, giving the expected sensation from the previous perception. Prediction error, coming from surprising events, provides a measure of the quality of the underlying sensory-motor contingencies. We show how a simple second-order controller (emotional system) based on the prediction progress allows the system to regulate its behavior to solve complex navigation tasks and also succeeds in asking for help if it detects dead-lock situations. We propose that this model could be a key structure toward self-assessment and autonomy. We made several experiments that can account for such properties for two different strategies (road following and place cells based navigation) in different situations. PMID:24115931

  12. From Self-Assessment to Frustration, A Small Step Towards Autonomy in Robotic Navigation.

    Directory of Open Access Journals (Sweden)

    Adrien eJauffret

    2013-10-01

    Full Text Available Autonomy and self-improvement capabilities are still challenging in the fields of robotics and machine learning. Allowing a robot to autonomously navigate in wide and unknown environments not only requires a repertoire of robust strategies to cope with miscellaneous situations, but also needs mechanisms of self-assessment for guiding learning and for monitoring strategies. Monitoring strategies requires feedbacks on the behavior’s quality, from a given fitness system in order to take correct decisions.In this work, we focus on how a second-order controller can be used to (1 manage behaviors according to the situation and (2 seek for human interactions to improve skills. Following an incremental and constructivist approach, we present a generic neural architecture, based on an online novelty detection algorithm that may be able to self-evaluate any sensory-motor strategies. This architecture learns contingencies between sensations and actions, giving the expected sensation from the previous perception. Prediction error, coming from surprising events, provides a measure of the quality of the underlying sensory-motor contingencies. We show how a simple second-order controller (emotional system based on the prediction progress allows the system to regulate its behavior to solve complex navigation tasks and also succeeds in asking for help if it detects dead-lock situations.We propose that this model could be a key structure toward self-assessment and autonomy. We made several experiments that can account for such properties for two different strategies (road following and place cells based navigation in different situations.

  13. Activation-induced cytidine deaminase (AID) is localized to subnuclear domains enriched in splicing factors

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yi, E-mail: yihooyi@gmail.com; Ericsson, Ida, E-mail: ida.ericsson@ntnu.no; Doseth, Berit, E-mail: berit.doseth@ntnu.no; Liabakk, Nina B., E-mail: nina.beate.liabakk@ntnu.no; Krokan, Hans E., E-mail: hans.krokan@ntnu.no; Kavli, Bodil, E-mail: bodil.kavli@ntnu.no

    2014-03-10

    Activation-induced cytidine deaminase (AID) is the mutator enzyme in adaptive immunity. AID initiates the antibody diversification processes in activated B cells by deaminating cytosine to uracil in immunoglobulin genes. To some extent other genes are also targeted, which may lead to genome instability and B cell malignancy. Thus, it is crucial to understand its targeting and regulation mechanisms. AID is regulated at several levels including subcellular compartmentalization. However, the complex nuclear distribution and trafficking of AID has not been studied in detail previously. In this work, we examined the subnuclear localization of AID and its interaction partner CTNNBL1 and found that they associate with spliceosome-associated structures including Cajal bodies and nuclear speckles. Moreover, protein kinase A (PKA), which activates AID by phosphorylation at Ser38, is present together with AID in nuclear speckles. Importantly, we demonstrate that AID physically associates with the major spliceosome subunits (small nuclear ribonucleoproteins, snRNPs), as well as other essential splicing components, in addition to the transcription machinery. Based on our findings and the literature, we suggest a transcription-coupled splicing-associated model for AID targeting and activation. - Highlights: • AID and its interaction partner CTNNBL1 localize to Cajal bodies and nuclear speckles. • AID associates with its activating kinase PKA in nuclear speckles. • AID is linked to the splicing machinery in switching B-cells. • Our findings suggest a transcription-coupled splicing associated mechanism for AID targeting and activation.

  14. Activation-induced cytidine deaminase (AID) is localized to subnuclear domains enriched in splicing factors

    International Nuclear Information System (INIS)

    Activation-induced cytidine deaminase (AID) is the mutator enzyme in adaptive immunity. AID initiates the antibody diversification processes in activated B cells by deaminating cytosine to uracil in immunoglobulin genes. To some extent other genes are also targeted, which may lead to genome instability and B cell malignancy. Thus, it is crucial to understand its targeting and regulation mechanisms. AID is regulated at several levels including subcellular compartmentalization. However, the complex nuclear distribution and trafficking of AID has not been studied in detail previously. In this work, we examined the subnuclear localization of AID and its interaction partner CTNNBL1 and found that they associate with spliceosome-associated structures including Cajal bodies and nuclear speckles. Moreover, protein kinase A (PKA), which activates AID by phosphorylation at Ser38, is present together with AID in nuclear speckles. Importantly, we demonstrate that AID physically associates with the major spliceosome subunits (small nuclear ribonucleoproteins, snRNPs), as well as other essential splicing components, in addition to the transcription machinery. Based on our findings and the literature, we suggest a transcription-coupled splicing-associated model for AID targeting and activation. - Highlights: • AID and its interaction partner CTNNBL1 localize to Cajal bodies and nuclear speckles. • AID associates with its activating kinase PKA in nuclear speckles. • AID is linked to the splicing machinery in switching B-cells. • Our findings suggest a transcription-coupled splicing associated mechanism for AID targeting and activation

  15. Hardware additions to microprocessor architecture aid software development

    Science.gov (United States)

    Sievers, M. W.

    1976-01-01

    An address trap (breakpoint) mechanism and last-in-first-out (LIFO) address stack are suggested as two additions to the basic microprocessor architecture whose functions are solely to aid the programmer. These devices provide the programmer with the ability to specify address breakpoints and to trace program execution back through N instructions, where N is the depth of the stack. Both devices, plus interface logic and buffering, have been designed for an INTEL 8080-based system using approximately 25 integrated-circuit packages.

  16. Virtual navigation strategies from childhood to senescence: evidence for changes across the life span

    Directory of Open Access Journals (Sweden)

    Veronique D Bohbot

    2012-11-01

    Full Text Available This study sought to investigate navigational strategies across the life span, by testing 8-year old children to 80-year old healthy older adults on the 4 on 8 virtual maze (4/8VM. The 4/8VM was previously developed to assess spontaneous navigational strategies, i.e. hippocampal-dependent spatial strategies (navigation by memorizing relationships between landmarks versus caudate nucleus-dependent response strategies (memorizing a series of left and right turns from a given starting position. With the 4/8VM, we previously demonstrated greater fMRI activity and grey matter in the hippocampus of spatial learners relative to response learners. A sample of 599 healthy participants was tested in the current study. Results showed that 84.4% of children, 46.3% of young adults, and 39.3% of older adults spontaneously used spatial strategies (p < 0.0001. Our results suggest that while children predominantly use spatial strategies, the proportion of participants using spatial strategies decreases across the life span, in favor of response strategies. Factors promoting response strategies include repetition, reward and stress. Since response strategies can result from successful repetition of a behavioral pattern, we propose that the increase in response strategies is a biological adaptive mechanism that allows for the automatization of behavior such as walking in order to free up hippocampal-dependent resources. However, the downside of this shift from spatial to response strategies occurs if people stop building novel relationships, which occurs with repetition and routine, and thereby stop stimulating their hippocampus. Reduced fMRI activity and grey matter in the hippocampus were shown to correlate with cognitive deficits in normal aging. Therefore, these results have important implications regarding factors involved in healthy and successful aging.

  17. Leading in times of crisis navigating through complexity, diversity and uncertainty to save your business

    CERN Document Server

    Dotlich, David L; Rhinesmith, Stephen H

    2009-01-01

    Praise for Leading in Times of Crisis ""Building on the solid base of their book Head, Heart, and Guts, Dotlich, Cairo, and Rhinesmith lay out the ways to become the kind of leader needed to navigate through today''s complexities and uncertainties. Leading in Times of Crisis is a necessary guidebook to survive and thrive in the global perfect storm.""-John Naisbitt, author, Megatrends and Megatrends 2000 ""The risks and opportunities that confront today''s leader have never been greater. Leading in Times of Crisis provides unique and valuable insights, along with straightforward principles, th

  18. New Method of Reconstruction from Nonparallel Stereo and Application to Surgical Navigator

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new method to reconstruct 3D scene points from nonparallel stereo is proposed. From a pair of conjugate images in an arbitrarily configured stereo system that has been calibrated, coordinates of 3D scene points can be computed directly using the method, bypassing the process of rectifying images or iterative solution involved in existing methods. Experiment results from both simulated data and real images validate the method. Practical application to surgical navigator shows that the method has advantages to improve efficiency and accuracy of 3D reconstruction from nonparallel stereo system in comparison with the conventional method that employs algorithm for standard parallel axes stereo geometry.

  19. Navigating the labyrinth : The path to progression for senior female managers working in a foreign country

    OpenAIRE

    Podowski, Camilla; Sundin, Malin

    2014-01-01

    Many articles have been written about women and what kind of barriers they face – whether it being a glass ceiling or a labyrinth - as they are progressing in their careers; gender stereotyping, double-binds, lack of role models, “old boys club”, different leadership styles, and so forth. And many others have talked about how to navigate or mitigate any obstacles that might face women due to their gender. Purpose of Research: This report aims to give insight into another aspect of this topic,...

  20. Pedestrian navigation using haptic feedback: Results from a field study to test spatial abilities and memory recall

    OpenAIRE

    Jacob, Ricky; Winstanley, Adam; Togher, Naomi; Roche, Richard

    2012-01-01

    Haptic feedback (using the sense of touch) or 'haptics' is a technology that provides forced feedback, vibrations, and/or motions to haptic-enabled user devices. The mobile haptic interaction model for a point to destination pedestrian navigation system is described. The importance of eyes-free, subtle feedback has been highlighted in previous work. This paper reports on the initial findings from the tests carried out to evaluate the user’s spatial abilities, navigations skills an...

  1. The Level of Effort in the National Response to HIV/AIDS: The AIDS Program Effort Index (API) 2003 Round

    OpenAIRE

    Joint United Nations Program on HIV/AIDS, UNAIDS; United States Agency for International Development, USAID; World Health Organization, WHO; POLICY Project, POLICY Project

    2003-01-01

    UNAIDS, USAID, and the POLICY Project developed the AIDS Program Effort Index (API) to measure program effort in the response to the HIV/AIDS epidemic. The index is designed to provide a current profile of national effort and a measure of change over time. The API was applied to 40 countries in 2000; a revised index was applied in 54 countries in early 2003. The results show that program effort is relatively high in the areas of political support, policies, and planning with average scores ab...

  2. Architectural design exposed: from computer-aided drawing to computer-aided design

    OpenAIRE

    RUFFLE, S

    1986-01-01

    Computer programs for architects and designers still do not 'understand' very much about what they are modelling or representing. In this paper the argument is put forward that as computer-aided design systems show increasing intelligence by employing data structures that more closely represent the way buildings go together, designers will find that they are relieved of manual tasks of representing the building design. This will be achieved by some restriction on the range of possible buildin...

  3. Beyond America’s War on Drugs: Developing Public Policy to Navigate the Prevailing Pharmacological Revolution

    Science.gov (United States)

    Golub, Andrew; Bennett, Alex S.; Elliott, Luther

    2015-01-01

    This paper places America’s “war on drugs” in perspective in order to develop a new metaphor for control of drug misuse. A brief and focused history of America’s experience with substance use and substance use policy over the past several hundred years provides background and a framework to compare the current Pharmacological Revolution with America’s Nineteenth Century Industrial Revolution. The paper concludes with cautions about growing challenges and provides suggestions for navigating this revolution and reducing its negative impact on individuals and society. PMID:25893215

  4. Foghorns to the Future: Using Knowledge and Transdisciplinarity to Navigate Complex Systems

    Directory of Open Access Journals (Sweden)

    Christo Fabricius

    2005-12-01

    Full Text Available Complex systems are shaped by cross-scale interactions, nonlinear feedbacks, and uncertainty, among other factors. Transdisciplinary approaches that combine participatory and conventional methods and democratize knowledge to enable diverse inputs, including those from local, informal experts, are essential tools in understanding such systems. The metaphor of a “bridge” to overcome the divide between different disciplines and knowledge systems is often used to advocate for more inclusive approaches. However, there is a shortage of information and consensus on the process, methodologies, and techniques that are appropriate to achieve this. This paper compares two case studies from Peru and South Africa in which community-level assessments were conducted as part of the Millennium Ecosystem Assessment, and explores the different conceptual models used to deal with scale and complexity, the methods adopted to deal with epistemology, and the different means of dealing with uncertainty in each assessment. The paper highlights the conceptual and practical challenges encountered by each assessment and discusses some of the conceptual and practical trade-offs involved in the selection of particular approaches. We argue that a boat navigating between unknown shores may be a more appropriate metaphor than a bridge, whose starting and end points are fixed and known.

  5. Algorithms for vehicle navigation

    OpenAIRE

    Storandt, Sabine

    2012-01-01

    Nowadays, navigation systems are integral parts of most cars. They allow the user to drive to a preselected destination on the shortest or quickest path by giving turn-by-turn directions. To fulfil this task the navigation system must be aware of the current position of the vehicle at any time, and has to compute the optimal route to the destination on that basis. Both of these subproblems have to be solved frequently, because the navigation system must react immediately if the vehicle leaves...

  6. What is the aggregate economic rate of return to foreign aid?

    OpenAIRE

    Arndt, Channing; Jones, Sam; Tarp, Finn

    2014-01-01

    Does foreign aid promote aggregate economic growth? In contrast to widespread perceptions, academic studies of this question have been rapidly converging towards a positive answer. We employ a simulation approach to (i) validate the coherence of recent empirics and (ii) calculate plausible ranges for the rate of return to aid. Our results highlight the long-run nature of aid investments and indicate the return to aid falls in ranges commonly accepted for public investments. We find no basis f...

  7. Discovery of Individual User Navigation Styles

    OpenAIRE

    Herder, E.; Juvina, I.

    2004-01-01

    Individual differences have been shown to lead to different navigation styles. In this paper we present a pilot study that aims at finding predictors for users’ vulnerability to experience disorientation that can be gathered unobtrusively and in real-time. We identified two navigation styles that we called flimsy navigation and laborious navigation that together predict users’ perceived disorientation. Our findings suggest that adaptive navigation support that addresses these navigation style...

  8. What are the public obligations to AIDS patients?

    Science.gov (United States)

    Kelley, David

    2002-01-01

    The operating assumption in most discussions of health policy is that government has some responsibility for the health of its citizens and that it may legitimately tax, subsidize, and regulate its citizens in the exercise of that responsibility. On this assumption, public obligations to HIV/AIDS patients are a function of their needs in relationship to other health needs. This paper challenges the operating assumption by arguing that it cannot be grounded in the obligations that individuals have to each other. The paper rests on its own assumption: the moral theory of individualism. On this theory, individuals are ends in themselves who have the right to choose their own actions and uses of their resources; they do not have unchosen obligations to help others. In regard to HIV/AIDS patients, consequently, individuals have no duty to help, nor any other obligation beyond that of respecting their rights; and there is no valid basis for government regulations or subsidies on their behalf. The paper argues against the two approaches commonly used to defend a more expansive view of individual obligations and the role of government. The first is the assumption of welfare rights to goods and services; the second is the assumption that distributive justice requires some redistribution of health care resources. PMID:15971567

  9. Data Mining to Facilitate Effective User Navigation and Improve Structure of a Website

    Directory of Open Access Journals (Sweden)

    Shweta Mohod,

    2014-08-01

    Full Text Available Now a days for a company it is very important to have active presence on web to become successful in electronic market. This requirement is fulfilled by an interactive website of a company. Website can be used to sell goods, maintain customer relationships, promotion of goods. By looking at the customer's response towards website we can decide campaign for future products and services. So for this website should be interactive and must be used by user by the way designer wants to. So, it is very important to study navigational behavior of a customer. By analyzing the web logs which records the navigational activity of the customer we can get several sequential patterns which helps us to study whether user is pursuing site's goal or not. Sequences are analyzed with WUM (Web Utilization Miner which gives g-sequence (Generalized Sequence and aggregate tree as an output. On the basis of the structure that is given by WUM, conclusions are studied and it is decided whether site structure needs improvement; The improvements suggested should be minimum but at the same time site should satisfy business goal. A mathematical programming model is used which suggest minimum improvements to site. Improvements which tends to change structure of site are avoided as it may be confusing for old site user.

  10. Multiorgan involvement due to cytomegalovirus infection in AIDS

    Directory of Open Access Journals (Sweden)

    Shounak Majumder

    2007-02-01

    Full Text Available Cytomegalovirus (CMV infection is a relatively late complication of AIDS. Like other viruses contributing to co-morbidity of HIV infection, cytomegalovirus has the propensity to cause multiorgan involvement. We report the case of a 34-year-old seropositive man who presented with bilateral lower limb weakness and symptomatic pallor. He was already on antiretroviral drugs for a month prior to presentation. Detailed clinical examination and laboratory investigations revealed cytomegalovirus polyradiculoneuropathy associated with bone marrow dysplasia. Dysplasia of haematopoeitic cell lines occurs in 30% to 70% of HIV infected patients, and is often indistinguishable from myelodysplastic syndrome. However, in our case, the bone marrow picture reverted back to normal with treatment of the CMV infection, pointing to a possible role of CMV as the causative agent of bone marrow dysplasia. Moreover, CMV has been incriminated as a pathogen producing the immune reconstitution inflammatory syndrome. The onset of the disease in our case one month after initiation of HAART strongly raises the possibility of this being a case of CMV related IRIS. This is the first reported case where IRIS has presented with CMV polyradiculoneuropathy and bone marrow dysplasia. We would like to highlight that in today's era of HIV care, clinicians should be aware of the possibility of multiorgan involvement by CMV, for appropriate management of this disease in the background of AIDS.

  11. Lymphocyte transformation response to pokeweed mitogen as a predictive marker for development of AIDS and AIDS related symptoms in homosexual men with HIV antibodies

    DEFF Research Database (Denmark)

    Hofmann, B; Lindhardt, B O; Gerstoft, J;

    1987-01-01

    To identify factors that may predict the development of the acquired immune deficiency syndrome (AIDS) or AIDS related symptoms various immunological measurements were studied in a group of homosexual men attending screening clinics for AIDS in Copenhagen. Fifty seven men whose ratio of T helper...

  12. 78 FR 14799 - Solicitation of Nominations to the Presidential Advisory Council on HIV/AIDS

    Science.gov (United States)

    2013-03-07

    ... HUMAN SERVICES Solicitation of Nominations to the Presidential Advisory Council on HIV/AIDS AGENCY... Presidential Advisory Council on HIV/AIDS (referred to as PACHA and/or the Council) is governed by provisions... Presidential Advisory Council on HIV/AIDS (PACHA). The PACHA is a federal advisory committee within...

  13. Positioning with Inertial Sensors and Aid Sensors when loosing GPS Fix

    OpenAIRE

    Mathiassen, Kim

    2010-01-01

    This thesis designs a multipurpose navigation unit. The unit is equipped with a GPS which is the primary navigation sensor, when the GPS satellites are available. If the GPS satellites becomes unavailable, a inertial system with aid sensors is used for navigation. A unit that collects data from a GPS, gyroscopes, accelerometers, magnetometers and a barometer has been developed in a project leading to this thesis. The software development was not completed. The software responsible for commun...

  14. Electromagnetic Interference Assessment of CDMA and GSM Wireless Phones to Aircraft Navigation Radios

    Science.gov (United States)

    Ely, Jay J.; Nguyen, Truong X.; Koppen, Sandra V.; Salud, M. Theresa

    2002-01-01

    To address the concern for cellular phone electromagnetic interference (EMI) to aircraft radios, a radiated emission measurement process for CDMA (IS-95) and GSM (ETSI GSM 11.22) wireless handsets was developed. Spurious radiated emissions were efficiently characterized from devices tested in either a semi-anechoic or reverberation chamber, in terms of effective isotropic radiated power. Eight representative handsets (4 GSM, 4 CDMA) were commanded to operate while varying their radio transmitter parameters (power, modulation, etc.). This report provides a detailed description of the measurement process and resulting data, which may subsequently be used by others as a basis of consistent evaluation for cellular/PCS phones, Bluetooth, IEEE802.11b, IEEE802.11a, FRS/GMRS radios, and other portable transmitters. Aircraft interference path loss (IPL) and navigation radio interference threshold data from numerous reference documents, standards, and NASA partnerships were compiled. Using this data, a preliminary risk assessment is provided for CDMA and GSM wireless phone interference to aircraft localizer, Glideslope, VOR, and GPS radio receivers on typical transport airplanes. The report identifies where existing data for device emissions, IPL, and navigation radio interference thresholds needs to be extended for an accurate risk assessment for wireless transmitters in aircraft.

  15. Scientists Grow Therapeutic Protein in Engineered Soya Bean Seeds to Prevent AIDS | Poster

    Science.gov (United States)

    Genetically modified soya beans provide a scalable, low-cost method of producing microbicides that prevent AIDS, a technique sustainable for resource-poor countries where AIDS is spreading rapidly. According to the Joint United Nations Programme on HIV/AIDS, more than 36 million people worldwide are living with HIV. While the number of AIDS-related deaths are decreasing, infection rates are still increasing, specifically in Eastern and Southern Africa.

  16. The Use of a Brain Computer Interface Remote Control to Navigate a Recreational Device

    OpenAIRE

    Shih Chung Chen; Aaron Raymond See; Yeou Jiunn Chen; Chia Hong Yeng; Chih Kuo Liang

    2013-01-01

    People suffering from paralysis caused by serious neural disorder or spinal cord injury also need to be given a means of recreation other than general living aids. Although there have been a proliferation of brain computer interface (BCI) applications, developments for recreational activities are scarcely seen. The objective of this study is to develop a BCI-based remote control integrated with commercial devices such as the remote controlled Air Swimmer. The brain is visually stimulated usin...

  17. Remarks to SBS PCM based self-navigation of laser drivers

    Science.gov (United States)

    Kalal, M.; Matena, L.; Kong, HJ; Martinkova, M.; Cha, S.

    2016-03-01

    A novel technology of self-navigation of laser drivers on injected inertial fusion energy pellets employing phase conjugating mirrors based on stimulating Brillouin scattering was recently proposed. Its feasibility as well as various implications were gradually studied and working solutions to potential problems were always suggested. As this technology could help to overcome several burning key issues of inertial fusion (e.g., a sufficiently precise navigation of laser drivers on injected pellets in the case of a direct drive scheme and decreased requirements on high-repetition high-power lasers) it gradually started to attract a carefully measured tentative interest among the major inertial fusion oriented laboratories and projects. In this paper the next step in this research path will be reported. It concerns the resulting phase and amplitude structures created by multiple low energy drivers (glints) illuminating the pellet during the first stage of the process after their reflection and a subsequent superposition on the collecting/focusing final optics. It was demonstrated that with a large number of such drivers acting simultaneously from many angles the situation gets somewhat complicated and requires more detailed studies/suggestions of suitable configurations.

  18. Development of Navigation Schemes for Grouped Mobile Robots Leading to Biomimetic Applications

    Directory of Open Access Journals (Sweden)

    Ming-Hsin Chen

    2012-03-01

    Full Text Available Biomimetic autonomous group manipulation of mobile robots has great potential in artificial intelligence, smart life, and automation related applications. In addition, it is also possible to use it as a tool for exploring the behavior of biological group motion in groups such as geese and fish. In order to fulfill these goals, fundamental capabilities of identification, navigation, and communication between robots must be established. In this work, key schemes are proposed for carrying out subsequent navigation tasks. By integrating omni-wheel mobile robots with X-Bee communication protocols, Arduino controls, IR range finders, and CMOS cameras, as well as with wiimote multi-zone localization, tasks such as obstacle and collision avoidance, object following, autonomous movement, and the indoor localization of group robots are implemented as the first step toward the autonomous control of group robots for subsequent biomimetic and smart life applications. With the resolution of these key issues, more realistic scenarios can be designed to achieve real group robot applications for indoor service in the future.

  19. Reimagining Financial Aid to Improve Student Access and Outcomes. Executive Summary

    Science.gov (United States)

    National Association of Student Financial Aid Administrators (NJ1), 2013

    2013-01-01

    As the student aid programs rapidly approach reauthorization in 2014, they continue to face severe funding and efficiency problems. With grant assistance from the Bill & Melinda Gates Foundation through their "Reimagining Aid Design and Delivery" (RADD) project, the National Association of Student Financial Aid Administrators (NASFAA) examined…

  20. Government Aid to Private Schools: Is It a Trojan Horse? A CIE Paper.

    Science.gov (United States)

    Wagner, Richard E., Ed.

    In this publication, six scholars interested in private education and knowledgeable in economic policy and politics present several different views of government aid to private schools. In the lead essay, William Cage argues that supporters of private schooling are shortsighted in advocating public aid for private education. Government aid, says…

  1. Vida/SIDA: A Grassroots Response to AIDS in Chicago's Puerto Rican Community

    Science.gov (United States)

    Sanabria, Roberto

    2004-01-01

    Chicago's Puerto Rican community in West Town had a unique reaction to the spread of AIDS within its limits. They created their own institutions and tackled the epidemic themselves. In its infancy, Vida/SIDA, which translates as Life/AIDS, was solely an alternative health clinic for people with AIDS. Free of charge, it provided services such as…

  2. 30 CFR 77.1704 - First aid training program; availability of instruction to all miners.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false First aid training program; availability of... WORK AREAS OF UNDERGROUND COAL MINES Miscellaneous § 77.1704 First aid training program; availability... shall make available to all miners employed in the mine a course of instruction in first aid...

  3. 14 CFR Appendix A to Part 121 - First Aid Kits and Emergency Medical Kits

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false First Aid Kits and Emergency Medical Kits A... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Pt. 121, App. A Appendix A to Part 121—First Aid Kits and Emergency Medical Kits Approved first-aid kits, at least one approved emergency medical kit,...

  4. [Progressive multifocal leukoencephalopathy and AIDS. Response to cytarabine].

    Science.gov (United States)

    Hervas Laguna, M J; Nieto Rodríguez, J A; Geijo Martínez, M P; Ruiz Ribo, M D; Borregón, S

    1994-05-01

    PML affects 4% of patients with AIDS and there is no effective treatment. Five cases of PML-AIDS have been described, showing clinical and radiological improvement after treatment with C-ara. We describe the case of a 33-year-old woman, addict to heroin, her clinical record including VIH infection, pneumonia by P. carinii, milliary tuberculosis, infection by virus B and C and treatment with AZT and tuberculostatics since January, 1992. In May, she began to develop a cerebellar syndrome. Images obtained with nuclear magnetic resonance were typical of PML. Subsequently, treatment with C-ara (2 mg/kg/day IV during 5 days each 4-6 weeks) was begun. From the third month of treatment on, the patient showed a clinical improvement and as of the sixth month, the affected areas of white substance were reduced in size. In addition, CD4 improved. Although in this patient a positive effect was observed after treatment with C-area, it should be verified in a controlled clinical trial. PMID:8061141

  5. The Concept of a Single Window in e-Navigation and According to the EU Regulations

    Directory of Open Access Journals (Sweden)

    Ryszard Wawruch

    2015-12-01

    Full Text Available Term single window can mean the point of contact for communication in relation: ship – shore and shore – ship. In this sense, it is mentioned for example in the IMO Resolution A.950(23 “Maritime Assistance Service (MAS” adopted on 5 December 2003. It can also mean a service or institution on land that collects all information related to safety of navigation before sending them on ships, as defined in the IMO documents on e-navigation. Directive 2010/65/EU of the European Parliament and of the Council of 20 October 2010 on reporting formalities for ships arriving in and/or departing from ports of the Member States and repealing Directive 2002/6/EC requires that vessels shall transmit reports mentioned in the IMO conventions and codes and European Union (EU and national legislations only once through the national single window established in each EU member state not later than on 1 June 2015. The question is whether these different functions of above-mentioned contact points can be implemented by one shore based institution or service. The article contains an analysis of these issues and tries to answer the set question.

  6. LIDAR-based relative navigation with respect to non-cooperative objects

    Science.gov (United States)

    Woods, John O.; Christian, John A.

    2016-09-01

    Most navigation solutions which make use of LIDAR for proximity operations with respect to non-cooperative objects rely on the iterative closest point, or ICP, algorithm. For correct convergence, ICP requires a good initial guess as to the 6 degree-of-freedom relative pose of a client object. Some solutions require manual pose initialization; and template matching - refined by ICP - was recently demonstrated as an automated solution for initialization. Additionally, some have used the output of one ICP iteration as the initial guess for the next, which is inherently dangerous (since bad ICP poses are propagated forward in time by the filter, by ICP, or by both; and because it introduces measurement errors that are correlated with the a priori state errors). We demonstrate the use of a method borrowed from personal robotics, OUR-CVFH (for Oriented, Unique, and Repeatable Clustered Viewpoint Feature Histograms), for rendezvous with a tumbling object in low earth orbit as well as an asteroid in a heliocentric orbit. Our strategy requires no initial pose estimate, and refines OUR-CVFH results with ICP; we demonstrate its utility as part of a full navigation solution with a dual-state inertial extended Kalman filter.

  7. 76 FR 35507 - Assistance to Southern Sudan and the United States Contribution to the Global Fund To Fight AIDS...

    Science.gov (United States)

    2011-06-17

    ... Assistance to Southern Sudan and the United States Contribution to the Global Fund To Fight AIDS... Waiver Determination under Section 202(d)(4)(A)(ii) of the United States Leadership against HIV/AIDS... determination under Section 202(d)(4)(A)(ii) of the United States Leadership Against HIV/AIDS, Tuberculosis,...

  8. Ship automation technology. Instrumentation and navigation; Senpaku ni okeru jidoka gijutsu no genjo. Keiso to kokai

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T. [Mitsui Engineering and Shipbuilding Co. Ltd., Tokyo (Japan)

    1996-02-01

    This paper summarizes facilities in automated vessels and automation technologies. The purpose of automation is to save energies, achieve navigation safety and high-efficiency navigation, and preserve the environment. Control theories required for automation include the PID control as a feedback control, and the feedforward control as a modern control theory. Actual installation of the automated systems may be enumerated as follows: remotely controlled wing operating and steering devices as power saving devices in ore transport vessels, hutch cover and ore removing device, totally remotely controlled ship mooring machine and one-man tug line device, and a sludge solidification treatment system; a merchant ship was installed with a controlling and monitoring system of marine devices consisting of a controlling and monitoring network for two systems, and a safety system network for two systems. The future marine vessel automating technology would advance in the areas of increasing speed and capacity and reducing size of computers and LANs as well as standardizing hardwares and softwares. As the automation trend in the futuristic vessels, proposals have been given on automating the centralized control and monitoring at an adequate level, improving the safety devices, considering more on energy conservation and environments, and improving the reliability. 5 refs., 4 figs., 6 tabs.

  9. Election to the Board of the Mutual Aid Fund

    CERN Multimedia

    Fonds d'Entraide

    2011-01-01

    Every year, the Board of the Mutual Aid Fund has to replace a proportion of its members. In accordance with article 6 of the Fund’s General Regulations, three members must leave and have to be replaced. These three members may subscribe again. All members of the CERN staff are eligible. If you are prepared to devote about two hours a month during working hours to assist your colleagues with financial problems, do not hesitate to join this self-governing Board. Candidates must announce their intention to stand for election by 1st Mars 2011. Fill in the present form and return it to P. Droux/FP (72265) or C. Potter/PH (74279) who will also be pleased to provide further information. Name, First Name Department Tel  

  10. Election to the Board of the Mutual Aid Fund

    CERN Multimedia

    Mutual Aid Fund

    2011-01-01

    Every year, the Board of the Mutual Aid Fund has to replace a proportion of its members. In accordance with article 6 of the Fund’s General Regulations, three members must leave and have to be replaced. These three members may subscribe again. All members of the CERN staff are eligible. If you are prepared to devote about two hours a month during working hours to assist your colleagues with financial problems, do not hesitate to join this self-governing Board. Candidates must announce their intention to stand for election by 1st Mars 2011. Fill in the present form and return it to P. Droux/FP (72265) or C. Potter/PH (74279) who will also be pleased to provide further information. Name, First Name ................................................................. Department .................................... Tel .............................

  11. Understanding large scale groundwater flow to aid in repository siting

    International Nuclear Information System (INIS)

    Atomic Energy of Canada Limited (AECL) with support from Ontario Hydro has developed a concept for the safe disposal of Canada's nuclear fuel waste in a deep (500 to 1000 m) mined repository in plutonic rocks of the Canadian Shield. The disposal concept involves the use of multiple engineered and natural barriers to ensure long-term safety. The geosphere, comprised of the enclosing rock mass and the groundwater which occurs in cracks and pores in the rock, is expected to serve as an important natural barrier to the release and migration of wastes from the engineered repository. Although knowledge of the physical and chemical characteristics of the groundwater in the rock at potential repository sites is needed to help design the engineered barriers of the repository it can also be used to aid in repository siting, to take greater advantage of natural conditions in the geosphere to enhance its role as a barrier in the overall disposal system

  12. Election to the Board of the Mutual Aid Fund

    CERN Multimedia

    Mutual Aid Fund

    2013-01-01

    Every two years, the Board of the Mutual Aid Fund has to replace a proportion of its members. In accordance with article 6 of the Fund’s General Regulations, three members must leave and have to be replaced. These three members may subscribe again. All members of the CERN staff are eligible. If you are prepared to devote about two hours a month during working hours to assist your colleagues with financial problems, do not hesitate to join this self-governing Board. Candidates must announce their intention to stand for election by 31st January 2014. Fill in the present form and return it to P. Droux/FP (72265) who will also be pleased to provide further information. Name, First Name ................................................................. Department .................................... Tel .............................

  13. Election to the Board of the Mutual Aid Fund

    CERN Multimedia

    Mutual Aid Fund

    2013-01-01

    Every two years, the Board of the Mutual Aid Fund has to replace a proportion of its members. In accordance with article 6 of the Fund’s General Regulations, three members must leave and have to be replaced. These three members may apply again. All members of the CERN staff are eligible. If you are prepared to devote about two hours a month during working hours to assist your colleagues with financial problems, do not hesitate to join this self-governing board. Candidates must announce their intention to stand for election by 31 January 2014. Fill in the present form and return it to P. Droux/FP (72265)  who will also be pleased to provide further information. Name, First Name: ................................................................. Department: .................................... Tel.: ..............................

  14. An approximate model for pulsar navigation simulation

    Science.gov (United States)

    Jovanovic, Ilija; Enright, John

    2016-02-01

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

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

    Science.gov (United States)

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

  16. Local Notice to Mariners by USCG District

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  17. USCG Local Notice to Mariners: 2003

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  18. USCG Local Notice to Mariners: 2011

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  19. USCG Local Notice to Mariners: 2001

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  20. USCG Local Notice to Mariners: 2007

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  1. USCG Local Notice to Mariners: 2008

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  2. USCG Local Notice to Mariners: 2000

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  3. USCG Local Notice to Mariners: 1999

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  4. USCG Local Notice to Mariners: 2009

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  5. USCG Local Notice to Mariners: 2004

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  6. USCG Local Notice to Mariners: 2006

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  7. USCG Local Notice to Mariners: 2010

    Data.gov (United States)

    Department of Homeland Security — The LNM is the primary means for disseminating information concerning aids to navigation, hazards to navigation, and other items of marine information of interest...

  8. Financial Aid: A Broken Bridge to College Access?

    Science.gov (United States)

    Long, Bridget Terry; Riley, Erin

    2007-01-01

    In this article, Bridget Terry Long and Erin Riley argue that in recent years, U.S. financial aid policy has shifted its emphasis from expanding college access for low-income students toward defraying the costs for middle- and upper-income families. They explain how loans, merit-based aid, and education tax breaks are increasingly replacing…

  9. Use of computer modeling to aid in hydraulic barrier design

    International Nuclear Information System (INIS)

    Releases of No. 6 and No. 4 fuel oil were discovered at a private boarding school. The releases impact a nearby pond with non-aqueous phase liquid hydrocarbon (NAPL), and threaten to impact an adjacent wetland. Prior to implementation of a permanent remedial solution, such as surfactant treatment and bioremediation, immediate containment of the NAPL was proposed via a barrier-gate containment system. The proposed barrier-gate containment system consisted of a high-density polyethylene barrier, horizontal wells, three flow-through gates, and downgradient infiltration galleries. Computer modeling of groundwater and NAPL flow was conducted utilizing a finite element multiphase model to evaluate the impacts to local hydrogeology associated with the barrier. These impacts included upgradient groundwater mounding and restriction of groundwater flux to the wetland. Model simulations aided in the identification of improvements to the initial barrier design and guided subsequent design modifications. Results of the simulations indicate the usefulness of computer modeling in containment system design

  10. Three Tools to Aid Visualisation of FITS Files for Astronomy

    CERN Document Server

    Mohan, P; Klapaukh, R; Johnston-Hollitt, M

    2016-01-01

    Increasingly there is a need to develop astronomical visualisation and manipulations tools which allow viewers to interact with displayed data directly, in real time and across a range of platforms. In addition, increases in dynamic range available for astronomical images with next generation telescopes have led to a desire to develop enhanced visualisations capable of presenting information across a wide range of intensities. This paper describes three new tools for astronomical visualisation and image manipulation that are the result of a collaboration between software engineers and radio astronomers. The first tool, FITS3D, is a fast, interactive 3D data cube viewer designed to allow real-time interactive comparisons of multiple spectral line data cubes simultaneously. It features region specific selection manipulation including smoothing. The second tool, FITS2D, aids the visualisation and manipulation of 2D fits images. The tool supports the interactive creation of free-form masks which allow the user to...

  11. Multicriteria decision aid application to a student selection problem

    Directory of Open Access Journals (Sweden)

    Juan Carlos Leyva López

    2005-04-01

    Full Text Available The selection of students is a complex decision making process, in which multiple selection criteria often need to be considered and where subjectiveness and imprecision are usually present, resulting that fuzzy and imprecise data should be used. This paper formulates the student selection process as a multicriteria decision analysis problem, concretely as a ranking problem, by using the ELECTRE III methodology to construct a fuzzy outranking relation, and then a genetic algorithm to exploit it and to obtain a ranking in decreasing order of preference. An empirical study of a real selection problem in the Universidad de Occidente in Mexico is presented. After performing calculations and obtaining the final ranking of compared alternatives, a sensitivity analysis was carried out. The study was supported with a new decision aid system for rank a finite set of multicriteria alternatives.

  12. Symmetric Synchronous Collaborative Navigation

    OpenAIRE

    Gerosa, Luca; Giordani, Alessandra; Ronchetti, Marco

    2004-01-01

    Synchronous collaborative navigation is a form of social navigation where users virtually share a web browser. In this paper, we present a symmetric, proxy-based architecture where each user can take the lead and guide others in visiting web sites, without the need for a special browser or other software. We show how we have applied this scheme to a problem-solving-oriented e-learning system.

  13. Cassini's Maneuver Automation Software (MAS) Process: How to Successfully Command 200 Navigation Maneuvers

    Science.gov (United States)

    Yang, Genevie Velarde; Mohr, David; Kirby, Charles E.

    2008-01-01

    To keep Cassini on its complex trajectory, more than 200 orbit trim maneuvers (OTMs) have been planned from July 2004 to July 2010. With only a few days between many of these OTMs, the operations process of planning and executing the necessary commands had to be automated. The resulting Maneuver Automation Software (MAS) process minimizes the workforce required for, and maximizes the efficiency of, the maneuver design and uplink activities. The MAS process is a well-organized and logically constructed interface between Cassini's Navigation (NAV), Spacecraft Operations (SCO), and Ground Software teams. Upon delivery of an orbit determination (OD) from NAV, the MAS process can generate a maneuver design and all related uplink and verification products within 30 minutes. To date, all 112 OTMs executed by the Cassini spacecraft have been successful. MAS was even used to successfully design and execute a maneuver while the spacecraft was in safe mode.

  14. Using Time Zones and Celestial Navigation to Teach the Phases of the Moon

    Science.gov (United States)

    O'Donoghue, A.

    2011-09-01

    The phases of the moon are typically presented to introductory astronomy classes in a diagram showing the position of the moon, its appearance and elongation at each phase, and the time of each phase's transit. Though wonderfully compact and efficient at conveying information, I have found it to be overwhelming to non-science major students. Much of their difficulty arises from their vague definition of time, which must be broadened for them to understand the different rising, transit, and setting times for the phases of the moon. Working with time zones helps them recognize that the time on their watch is relative to a particular longitude and the transit of the sun at that longitude. Celestial Navigation extends this to the transit of all celestial objects and helps them re-define "time of day" to a position on Earth relative to the Earth-Sun line in a practical way. Once they understand why a given object transits at the same time for all time zones, extending this to the moon is much simpler. My students are quickly able to identify the transit times of the various phases of the moon, and with some additional instruction, quickly learn how to figure out their rising and setting times as well. On this poster, I will include images from PowerPoint animations and the student exercises I use to help them understand the concepts. Though I have too small a sample for statistical analysis (24 students/semester), I have found that student scores on moon phase questions on exams have improved since I incorporated time zones and celestial navigation into my course.

  15. Cross Functional Career Navigation: The Way to Broaden Your Career Options

    Science.gov (United States)

    Greenhalgh, Todd

    2000-03-01

    In today's rapid paced global environment, broadening career options for career development depends on successful cross-functional career navigation. For scientists and engineers, this means developing a diversity of skills in addition to a strong technical foundation. Fortunately, companies use cross-functional teams as one of the key tools for rapidly developing and commercializing products and services. Participation on these teams carries with it the additional benefit of allowing an individual to develop new skills, and to gain valuable expertise in areas that are critical to the growth of their company, their industry and, most importantly, their career. This talk will outline some of the important cross functional skills that can propel your career ahead and ways in which you can take charge of your career mapping and enhance your value and employability.

  16. Adding memory processing behaviors to the fuzzy behaviorist-based navigation of mobile robots

    Energy Technology Data Exchange (ETDEWEB)

    Pin, F.G.; Bender, S.R.

    1996-05-01

    Most fuzzy logic-based reasoning schemes developed for robot control are fully reactive, i.e., the reasoning modules consist of fuzzy rule bases that represent direct mappings from the stimuli provided by the perception systems to the responses implemented by the motion controllers. Due to their totally reactive nature, such reasoning systems can encounter problems such as infinite loops and limit cycles. In this paper, we proposed an approach to remedy these problems by adding a memory and memory-related behaviors to basic reactive systems. Three major types of memory behaviors are addressed: memory creation, memory management, and memory utilization. These are first presented, and examples of their implementation for the recognition of limit cycles during the navigation of an autonomous robot in a priori unknown environments are then discussed.

  17. Automatic fuzzy rule generation and its application to the navigation control for mobile robot

    International Nuclear Information System (INIS)

    This paper presents an approach to building multi-input and single output fuzzy models. Such a model is composed of fuzzy implications, and its output is inferred by simplified reasoning. The implications are automatically generated by the structure and parameter identification. In the structure identification, the optimal or near optimal number of fuzzy implications is determined in view of valid partition of data set. The parameters defining the implications are identified by a gradient method to minimize mean square errors. Numerical examples are provided to evaluate the feasibility of the proposed number of fuzzy implications than the ones achieved previously in other methods. The proposed approach has also been applied to construct a fuzzy model for the navigation control of a mobile robot. The validity of the resultant model is demonstrated by experimentation. (author)

  18. mpact of ice conditions to the navigation in the Novaya Zemlya and Spitsbergen region in XVI–XVII centuries

    Directory of Open Access Journals (Sweden)

    V. L. Derzhavin

    2015-03-01

    Full Text Available In the 16th–17th centuries, West European navigators made numerous but mostly unsuccessful efforts to open a new way, i.e. the North-East Passage, to China and India. Among three possible routes of that time the basic one ran through straits of the Vaigach Island but it was almost impassable due to heavy ice situation. At the same time Russian merchants regularly went on their ships from Pomorie to Siberian river mouths, and in the opposite direction, though they did also meet complicated ice situations. Russian navigator and geographer F.P. Litke (1797–1882 noticed that the ice situation in one or another region of the Barents Sea seriously changed from year to year. Russian navigation started in the Russian Pomorie (littoral region of the Russian Arctic not earlier than at end of June – beginning of July but Europeans knew nothing about this. Because of this, their ships came to the Vaigach region either earlier or later of the time when it was possible to go through the straits. Most often, they came here in the first half- and mid-August. Thus, western sailors could not get this quite narrow navigation «window» of pomors (Russian navigators. And if sometimes (rather rarely they could catch the right time and go through the strait Yugorski Shar they met extremely heavy ice situation in the Kara Sea. Perhaps for this reason, almost all European expeditions of that time failed.

  19. AIDS Kaposi sarcoma-derived cells produce and respond to interleukin 6

    International Nuclear Information System (INIS)

    Cell lines derived from Kaposi sarcoma lesions of patients with AIDS (AIDS-KS cells) produce several cytokines, including an endothelial cell growth factor, interleukin 1β, and basic fibroblast growth factor. Since exposure to human immunodeficiency virus increases interleukin 6 (IL-6) production in monocytes and endothelial cells produce IL-6, the authors examined IL-6 expression and response in AIDS-KS cell lines and IL-6 expression in AIDS Kaposi sarcoma tissue. The AIDS-KS cell lines (N521J and EKS3) secreted large amounts of immunoreactive and biologically active IL-6. The authors found both IL-6 and IL-6 receptor (IL-6-R) RNA by slot blot hybridization analysis of AIDS-KS cells. The IL-6-R was functional, as [3H]thymidine incorporation by AIDS-KS cells increased significantly after exposure to human recombinant IL-6 (hrIL-6) at >10 units/ml. When AIDS-KS cells (EKS3) were exposed to IL-6 antisense oligonucleotide, cellular proliferation decreased by nearly two-thirds, with a corresponding decrease in the production of IL-6. These results show that both IL-6 and IL-6-R are produced by AIDS-KS cells and that IL-6 is required for optimal AIDS-KS cell proliferation, and they suggest that IL-6 is an autocrine growth factor for AIDS-KS cells

  20. Learning for autonomous navigation : extrapolating from underfoot to the far field

    Science.gov (United States)

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

    2005-01-01

    Autonomous off-road navigation of robotic ground vehicles has important applications on Earth and in space exploration. Progress in this domain has been retarded by the limited lookahead range of 3-D sensors and by the difficulty of preprogramming systems to understand the traversability of the wide variety of terrain they can encounter. Enabling robots to learn from experience may alleviate both of these problems. We define two paradigms for this, learning from 3-D geometry and learning from proprioception, and describe initial instantiations of them we have developed under DARPA and NASA programs. Field test results show promise for learning traversability of vegetated terrain, learning to extend the lookahead range of the vision system, and learning how slip varies with slope.

  1. [Evolution of total knee arthroplasty : From robotics and navigation to patient-specific instruments].

    Science.gov (United States)

    Haaker, R

    2016-04-01

    In this article the evolution beginning with the robotics of total knee arthroplasty to CT-based and kinematic navigation and patient-specific instruments is described. Thereby it is pointed out that in the early 1990s, CT imaging solely for the planning of a knee endoprosthesis was considered as obsolete radiation exposure and this led to the widespread development of kinematical systems.Also a patient specific planning tool based on CAD built acryl harz blocs existed at the time. There is an ongoing process of implanting total knee arthroplasties in a more exact position. Nowadays the new evolution of soft tissue balancing by using a kinematic alignment has put these efforts into perspective. PMID:27025867

  2. Comparing the Usefulness of Video and Map Information In Navigation Tasks

    Energy Technology Data Exchange (ETDEWEB)

    Curtis W. Nielsen; Michael A. Goodrich

    2006-03-01

    One of the fundamental aspects of robot teleoperation is the ability to successfully navigate a robot through an environment. We define successful navigation to mean that the robot minimizes collisions and arrives at the destination in a timely manner. Often video and map information is presented to a robot operator to aid in navigation tasks. This paper addresses the usefulness of map and video information in a navigation task by comparing a side-by-side (2D) representation and an integrated (3D) representation in both a simulated and a real world study. The results suggest that sometimes video is more helpful than a map and other times a map is more helpful than video. From a design perspective, an integrated representation seems to help navigation more than placing map and video side-by-side.

  3. The constructional conception of the effectiveness of navigational service rising for navigation on inland water routes

    OpenAIRE

    I. V. Tykhonov

    2010-01-01

    Constructional conception of rising of the effectiveness of navigational service on inland water routes is described. The article demonstrates that using of this conception and informational recourses permit to raise the effectiveness of navigational service of safety of navigation

  4. Model-base visual navigation of a mobile robot

    International Nuclear Information System (INIS)

    The thesis considers the problems of visual guidance of a mobile robot. A visual navigation system is formalized consisting of four basic components: world modelling, navigation sensing, navigation and action. According to this formalization an experimental system is designed and realized enabling real-world navigation experiments. A priori knowledge of the world is used for global path finding, aiding scene analysis and providing feedback information to the close the control loop between planned and actual movements. Two world models were developed. The first approach was a map-based model especially designed for low-level description of indoor environments. The other was a higher level and more symbolic representation of the surroundings utilizing the spatial graph concept. Two passive vision approaches were developed to extract navigation information. With passive three- camera stereovision a sparse depth map of the scene was produced. Another approach employed a fish-eye lens to map the entire scene of the surroundings without camera scanning. The local path planning of the system is supported by three-dimensional scene interpreter providing a partial understanding of scene contents. The interpreter consists of data-driven low-level stages and a model-driven high-level stage. Experiments were carried out in a simulator and test vehicle constructed in the laboratory. The test vehicle successfully navigated indoors

  5. Application of genetic algorithm to computer-aided process

    OpenAIRE

    Amrinder Chahal

    2012-01-01

    Process planning is a task of transforming design specifications into manufacturing instructions. It is an engineering task that determinesthe detailed manufacturing requirements for transforminga raw material into a completed part, within the available machining resources. The output of process planning generally includes operations, machine tools, cutting tools, fixtures, machining parameters, etc. Computer-aided process planning (CAPP) is an important interface between computer-aided desig...

  6. Integrated navigation method based on inertial navigation system and Lidar

    Science.gov (United States)

    Zhang, Xiaoyue; Shi, Haitao; Pan, Jianye; Zhang, Chunxi

    2016-04-01

    An integrated navigation method based on the inertial navigational system (INS) and Lidar was proposed for land navigation. Compared with the traditional integrated navigational method and dead reckoning (DR) method, the influence of the inertial measurement unit (IMU) scale factor and misalignment was considered in the new method. First, the influence of the IMU scale factor and misalignment on navigation accuracy was analyzed. Based on the analysis, the integrated system error model of INS and Lidar was established, in which the IMU scale factor and misalignment error states were included. Then the observability of IMU error states was analyzed. According to the results of the observability analysis, the integrated system was optimized. Finally, numerical simulation and a vehicle test were carried out to validate the availability and utility of the proposed INS/Lidar integrated navigational method. Compared with the test result of a traditional integrated navigation method and DR method, the proposed integrated navigational method could result in a higher navigation precision. Consequently, the IMU scale factor and misalignment error were effectively compensated by the proposed method and the new integrated navigational method is valid.

  7. Assistência aos pacientes com HIV/Aids no Brasil Health care to HIV/AIDS patients in Brazil

    Directory of Open Access Journals (Sweden)

    Margareth Crisóstomo Portela

    2006-04-01

    Full Text Available O trabalho teve por objetivo avaliar a assistência à população com Aids no Brasil e a capacidade do Sistema Único de Saúde (SUS de prover intervenções para enfrentamento da epidemia e discutir a sustentabilidade da iniciativa brasileira de distribuição universal e gratuita dos anti-retrovirais. O trabalho considerou dados originais de uma pesquisa sobre a capacidade potencial de distribuição de uma futura vacina anti-HIV no Brasil, envolvendo 119 entrevistados. Nas abordagens da assistência hospitalar e da assistência farmacêutica foram utilizados dados do Sistema de Informações Hospitalares do SUS e do Sistema de Controle Logístico de Medicamentos do Programa Nacional de DST/Aids. Os resultados mostraram bom desempenho da política de distribuição de anti-retrovirais. Entretanto, o acesso ao tratamento de doenças oportunistas foi deficitário. Os valores pagos pelo Sistema Único de Saúde pelas internações por Aids mantiveram-se muito baixos, com valor médio em torno de R$700,00, em 2004. A assistência a pacientes com HIV/Aids no Brasil tem sido tratada como um direito do cidadão, com o respaldo de uma articulação efetiva entre as esferas de governo e a sociedade civil. Os desafios que se colocam atualmente dizem respeito ao monitoramento mais fino dos processos e resultados obtidos e à sustentabilidade da distribuição universal e gratuita de anti-retrovirais.This study was intended to assess care provided to those living with HIV/AIDS in Brazil and the Brazilian Unified Health System (SUS capacity of delivering interventions to cope with the epidemic as well as to discuss the sustainability of the Brazilian initiative of providing universal free access to antiretrovirals (ARVs. Original data from a study comprising 119 respondents on the potential capacity of delivering a prospective HIV vaccine in Brazil was used. Inpatient and pharmaceutical care was based on data from the SUS Hospital Information System and

  8. Electronic aids to daily living: be able to do what you want.

    LENUS (Irish Health Repository)

    Verdonck, Michèle Claire

    2011-01-01

    This study explores the experiences of Irish people with high cervical spinal cord injuries living with electronic aids to daily living (EADL) and the meaning attributed to such systems in the context of participation in everyday life.

  9. Public Reactions to People with HIV/AIDS in the Netherlands

    OpenAIRE

    van der Bos, Arjan; Kok, Gerjo; Dijker, Anton

    2001-01-01

    textabstractA national telephone survey was conducted (1) to assess present-day public reactions to people with HIV/AIDS in the Netherlands, (2) to measure how knowledge about highly active antiretroviral therapy (HAART) is related to public reactions to people with HIV/AIDS, and (3) to investigate determinants of willingness to have personal contact with people with HIV/AIDS. Dutch adults (N = 751) participated in a telephone interview conducted to measure cognitive, emotional and behavioral...

  10. Evaluating adherence to ocular hypotensives using the Travatan dosing aid

    Directory of Open Access Journals (Sweden)

    O'Dell L

    2012-01-01

    Full Text Available Leslie O'Dell1, Amy L Hennessy2,3, Alan L Robin2–41May Eye Care Center, Hanover, PA, USA; 2Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; 3Glaucoma Specialists, Baltimore, MD, USA; 4Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USAPurpose: The Travatan™ Dosing Aid (TDA is the first commercially available device designed to aid in patients' adherence to their glaucoma therapies and to record patients' eyedrop administration, so that doctors can better assess adherence. No prior studies have objectively evaluated adherence to glaucoma medications and its relationship to the severity of glaucoma or the use of multiple systemic medications.Methods: We enrolled 100 consecutive subjects from a private glaucoma practice, all currently using topical travoprost 0.004%. Each subject was issued a TDA to record the time and date of each drop instilled. Informed consents were signed and the subjects were aware that their medication use was being monitored. Patients returned for follow-up 30–60 days after their initial exam.Results: 89 subjects completed the study: 44 were male, with a mean age of 67 years, and 69.7% were Caucasian. Overall, patient adherence was 74.8% (range 22%–100% improving to 85.4% on the day prior to follow-up. The mean number of missed doses per month was 6.24 ± 5.9. Only 7.9% of the study population never missed a dose and 23.6% ± 4.3% missed more than ten drops per month. No marked association was observed between the severity of glaucoma, race, or the number of systemic medications and adherence. A marked improvement in adherence was noted in patients using travoprost 0.004% as monocular therapy rather than binocular therapy, 84.0% ± 17.1% vs 67.4% ± 23.5% (P < 0.005.Conclusion: Patient adherence to glaucoma medical therapy is a major barrier in the management and treatment of glaucoma patients given the chronic nature and asymptomatic course of the disease. Until recently

  11. The orphaning experience: descriptions from Ugandan youth who have lost parents to HIV/AIDS

    OpenAIRE

    Ssebunnya Joshua; Jack Susan; Harms Sheila; Kizza Ruth

    2010-01-01

    Abstract The HIV/AIDS epidemic has continued to pose significant challenges to countries in Sub-Saharan Africa. Millions of African children and youth have lost parents to HIV/AIDS leaving a generation of orphans to be cared for within extended family systems and communities. The experiences of youth who have lost parents to the HIV/AIDS epidemic provide an important ingress into this complex, evolving, multi-dimensional phenomenon. A fundamental qualitative descriptive study was conducted to...

  12. PERFORMANCE CHARACTERISTIC MEMS-BASED IMUs FOR UAVs NAVIGATION

    Directory of Open Access Journals (Sweden)

    H. A. Mohamed

    2015-08-01

    Full Text Available Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK, and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS signal outage.

  13. Performance Characteristic Mems-Based IMUs for UAVs Navigation

    Science.gov (United States)

    Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

    2015-08-01

    Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

  14. Sensitivity analysis of helicopter IMC decelerating steep approach and landing performance to navigation system parameters. [Instrument Meteorological Conditions

    Science.gov (United States)

    Karmali, M. S.; Phatak, A. V.; Bull, J. S.; Peach, L. L.; Demko, P. S.

    1984-01-01

    The present investigation is concerned with a sensitivity analysis of the Decelerated Steep Approach and Landing (DSAL) maneuver to on-board and ground-based navigation system parameters. The Instrument Meteorological Conditions (IMC) DSAL maneuver involves decelerating to zero range rate while tracking the localizer and glideslope. The considered study investigated the performance of the navigation systems using Constant Deceleration Profile (CDP) guidance and a six degrees glideslope trajectory. A closed-loop computer simulation of the UH1H helicopter DSAL system was developed for the sensitivity analysis. Conclusions on system performance parameter sensitivity are discussed.

  15. First aid to Cultural Heritage. Training initiatives on rapid documentation

    Science.gov (United States)

    Almagro Vidal, A.; Tandon, A.; Eppich, R.

    2015-08-01

    Recent dramatic events have brought to the forefront the debate on how to protect, safeguard and document Cultural Heritage in conflict areas. Heritage places have become battlefields, sources of illicit trafficking and even deliberate targets of destruction because of the politicisation to further conflict ideologies as well as misinterpretation of the values they represent. Is it possible to protect Cultural Heritage under such circumstances? If yes, when is the right time to intervene and who can help in this task? How can documentation and training assist? The International Course on First Aid to Cultural Heritage in Times of Crisis promoted by ICCROM (The International Centre for the Study of the Preservation and Restoration of Cultural Property) in collaboration with various partners focuses specifically on ways to help in such difficult and stressful situations. This paper explores the methodological approach and highlights the special circumstances that surround rapid documentation and preliminary condition assessment in conflict areas, and in cases of complex emergencies such as an earthquake striking a conflict area. The paper identifies international actors that might play a special and crucial role in the first steps of such a situation and recognizes the need for training activities to strengthen capacities for disaster response to cultural heritage at national and regional levels.

  16. Ser mãe e estar com AIDS: revivescimento do pecado original To be mother and to have AIDS: the original evil reviviscency

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Duarte Pereira

    1999-12-01

    Full Text Available O estudo objetivou compreender o significado de estar com AIDS para mães portadoras do HIV/AIDS, identificar as emoções e os modos de enfrentamento decorrentes da relação mãe-filho sadio. Realizado à luz da teoria das representações sociais, teve como resultante "ser mãe" e "estar com AIDS" representado como um processo que não se esgota na doença, mas mostra-se vinculado à polaridade do bem e do mal. Traz ainda a sexualidade como algo que contém essas polaridades e a AIDS, vinculada ao aspecto mal. As mulheres deste estudo mostraram se julgar culpadas de algo e merecem o castigo imposto pela doença.This study aimed to understand the meaning of being with AIDS among HIV/AIDS mothers. It looks for to identify the emotions and the way of cope with the situation as a mother has a healthy son. This study was conducted based on the Social Representations Theory. The findings showed "to be mother" and "to have AIDS" represented as a process that does not finish in the disease itself Also it was found that there is a polarize link between the good and the evil. Indeed, this study brought the sexuality likewise the polarized link, being AIDS linked to evil aspect. These women from this study had perceived themselves as guilty of something, as a result, they deserved the punishment that the AIDS imposed on them.

  17. Acute HIV infection with rapid progression to AIDS

    Directory of Open Access Journals (Sweden)

    Marcio de Oliveira Silva

    2010-06-01

    Full Text Available Acute HIV infection is rarely recognized as the signs and symptoms are normally unspecific and can persist for days or weeks. The normal HIV course is characterized by a progressive loss of CD4+ cells, which normally leads to severe immunodeficiency after a variable time interval. The mean time from initial infection to development of clinical AIDS is approximately 8-10 years, but it is variable among individuals and depends on a complex interaction between virus and host. Here we describe an extraordinary case of a man who developed Pneumocisits jiroveci pneumonia within one month after sexual exposure to HIV-1, and then presented with 3 consecutive CD4 counts bellow 200 cells/mm³ within 3 months, with no other opportunistic disease. Although antiretroviral therapy (AZT+3TC+ATZ/r was started, with full adherence of the patient, and genotyping indicating no primary antiretroviral resistance mutations, he required more than six months to have a CD4 restoration to levels above 200 cells/mm³ and 10 months to HIV-RNA to become undetectable.

  18. Strategies of media marketing for "America Responds to AIDS" and applying lessons learned.

    OpenAIRE

    Keiser, N H

    1991-01-01

    The Centers for Disease Control's (CDC) public service announcement (PSA) campaign on acquired immunodeficiency syndrome (AIDS), entitled "America Responds to AIDS," has provided an opportunity to examine various media marketing techniques and their effectiveness in setting and sustaining a national media agenda for public health. The overall objective was to enlist the media as a partner in the effort to establish a clear national public health agenda on AIDS by reaching as many Americans as...

  19. Strategies to reduce mortality and morbidity due to AIDS-related cryptococcal meningitis in Latin America

    OpenAIRE

    Vidal, Jose E; Augusto C. Penalva de Oliveira; Dauar, Rafi F.; Boulware, David R.

    2013-01-01

    Latin America is the region with the third most AIDS-related cryptococcal meningitis infections globally. Highly active antiretroviral therapy (HAART) has reduced the number of infections; however, the number of deaths and the case-fatality rate continues to be unacceptable. In this review, we focus on the burden of AIDS-related cryptococcosis in Latin America and discuss potential strategies to reduce early mortality from Cryptococcus. In this review, we highlight the importance of: (1) earl...

  20. Exploring requirements for indoor navigation systems

    OpenAIRE

    Ni, Chunxiao

    2013-01-01

    Indoor navigation has been a subject in ubiquitous computing domain in the past decade. Recently many studies focus on exploring user requirements for indoor navigation systems and make effort in developing effective interactive systems to support indoor navigation. This study aims to find which kind of spatial representation and what orientation cues common users prefer to use for indoor navigation. An experiment was performed to examine the navigation effectiveness and user satisfaction wit...

  1. Measuring real-ear signal-to-noise ratio: application to directional hearing aids.

    Science.gov (United States)

    Bell, Steven L; Creeke, Sarah A; Lutman, Mark E

    2010-03-01

    Due to individual characteristics such as head size, earmould type, and earmould venting, the directional benefit that an individual will obtain from a hearing aid cannot be predicted from average data. It is therefore desirable to measure real ear directional benefit. This paper demonstrates a method to measure real ear hearing aid directivity based on a general approach to measure the broadband output signal-to-noise ratio of a hearing aid. Errors arising from non-linearity were tested in simulation and found to be low for typical hearing aid compression ratios. Next, the efficacy of the method to estimate directional benefit was demonstrated on KEMAR. Finally the variability of directional benefit was explored in real-ears. Significant differences in signal-to-noise ratio between directional and omnidirectional microphone settings were demonstrated at most azimuths. Articulation-Index-weighted directional benefit varied by more than 7 dB across ears at some azimuths. Such individual variation in directional benefit has implications when fitting hearing aids: it should not be assumed that all users will receive similar directional benefit from the same hearing aid. PMID:20151932

  2. Orion Exploration Flight Test-1 Post-Flight Navigation Performance Assessment Relative to the Best Estimated Trajectory

    Science.gov (United States)

    Gay, Robert S.; Holt, Greg N.; Zanetti, Renato

    2016-01-01

    This paper details the post-flight navigation performance assessment of the Orion Exploration Flight Test-1 (EFT-1). Results of each flight phase are presented: Ground Align, Ascent, Orbit, and Entry Descent and Landing. This study examines the on-board Kalman Filter uncertainty along with state deviations relative to the Best Estimated Trajectory (BET). Overall the results show that the Orion Navigation System performed as well or better than expected. Specifically, the Global Positioning System (GPS) measurement availability was significantly better than anticipated at high altitudes. In addition, attitude estimation via processing GPS measurements along with Inertial Measurement Unit (IMU) data performed very well and maintained good attitude throughout the mission.

  3. Using virtual objects to aid underground storage tank teleoperation

    International Nuclear Information System (INIS)

    In this paper we describe an algorithm by which obstructions and surface features in an underground storage tank can be modeled and used to generate virtual barrier function for a real-time telerobotic system, which provides an aid to the operator for both real-time obstacle avoidance and for surface tracking. The algorithm requires that the slave's tool and every object in the waste storage tank be decomposed into convex polyhedral primitives, with the waste surface modeled by triangular prisms. Intrusion distance and extraction vectors are then derived at every time step by applying Gilbert's polyhedra distance algorithm, which has been adapted for the task. This information is then used to determine the compression and location of nonlinear virtual spring-dampers whose total force is summed and applied to the manipulator/teleoperator system. Experimental results using a PUMA 560 and a simulated waste surface validate the approach, showing that it is possible to compute the algorithm and generate smooth, realistic pseudo forces for the teleoperator system using standard VME bus hardware

  4. Computer Aided Dosimetry and Verification of Exposure to Radiation

    Science.gov (United States)

    Waller, Edward; Stodilka, Robert Z.; Leach, Karen E.; Lalonde, Louise

    2002-06-01

    In the timeframe following the September 11th attacks on the United States, increased emphasis has been placed on Chemical, Biological, Radiological and Nuclear (CBRN) preparedness. Of prime importance is rapid field assessment of potential radiation exposure to Canadian Forces field personnel. This work set up a framework for generating an 'expert' computer system for aiding and assisting field personnel in determining the extent of radiation insult to military personnel. Data was gathered by review of the available literature, discussions with medical and health physics personnel having hands-on experience dealing with radiation accident victims, and from experience of the principal investigator. Flow charts and generic data fusion algorithms were developed. Relationships between known exposure parameters, patient interview and history, clinical symptoms, clinical work-ups, physical dosimetry, biological dosimetry, and dose reconstruction as critical data indicators were investigated. The data obtained was examined in terms of information theory. A main goal was to determine how best to generate an adaptive model (i.e. when more data becomes available, how is the prediction improved). Consideration was given to determination of predictive algorithms for health outcome. In addition. the concept of coding an expert medical treatment advisor system was developed (U)

  5. Hearing Aids

    Science.gov (United States)

    ... prefer the open-fit hearing aid because their perception of their voice does not sound “plugged up.” ... My voice sounds too loud. The “plugged-up” sensation that causes a hearing aid user’s voice to ...

  6. Brand Aid

    DEFF Research Database (Denmark)

    Richey, Lisa Ann; Ponte, Stefano

    A critical account of the rise of celebrity-driven “compassionate consumption” Cofounded by the rock star Bono in 2006, Product RED exemplifies a new trend in celebrity-driven international aid and development, one explicitly linked to commerce, not philanthropy. Brand Aid offers a deeply informed...

  7. “We, the AIDS people …”: How Antiretroviral Therapy Enables Zimbabweans Living With Aids to Cope With Stigma

    OpenAIRE

    Campbell, Catherine; Skovdal, Morten; Madanhire, Claudius; Mugurungi, Owen; Gregson, Simon; Nyamukapa, Constance

    2010-01-01

    We studied the impact of antiretroviral treatment (ART) availability on AIDS stigma through interviews with 118 ART users, AIDS caregivers, and nurses in Zimbabwe. Treatment enables positive social and economic participation through which users can reconstruct their shattered sense of social value. However, stigma remains strong, and ART users remain mired in conflictual symbolic relationships between “the AIDS people” and “the untested.” To date, the restoration of users’ own sense of self-w...

  8. Using hearing aid directional microphones and noise reduction algorithms to enhance cochlear implant performance

    OpenAIRE

    Chung, K; Zeng, F G; Waltzman, S

    2004-01-01

    Hearing aids and cochlear implants are two major hearing enhancement technologies but yet share little in research and development. The purpose of this study was to determine whether hearing aid directional microphones and noise reduction technologies could enhance cochlear implant users' speech understanding and ease of listening. Digital hearing aids serving as preprocessors were programmed to omni-directional microphone, directional microphone, and directional microphone plus noise reducti...

  9. Response to: Practice of first aid in burn related injuries in a developing country.

    Science.gov (United States)

    Baker, Benjamin; Amin, Kavit; Khor, Wee Sim; Khwaja, Nadeem

    2015-12-01

    Traditional remedies for burns first aid are rarely compliant with current best practice. Greater Manchester is one of the most ethnically diverse regions in the UK. Our burns centre has noted the prevalent use of traditional remedies over recognised first aid prior to presentation. We review traditional burns remedies and highlight the importance of burns first aid education that is accessible to migrant communities. PMID:26428366

  10. Transformações da "aids aguda" para a "aids crônica": percepção corporal e intervenções cirúrgicas entre pessoas vivendo com HIV e aids From "acute AIDS" to "chronic AIDS": body perception and surgical interventions in people living with HIV and AIDS

    Directory of Open Access Journals (Sweden)

    Tatianna Meireles Dantas de Alencar

    2008-12-01

    Full Text Available Após dez anos de uso da terapia anti-retroviral de alta potência, um novo problema surge: a síndrome lipodistrófica do HIV, uma distribuição irregular de gordura no corpo, decorrente do uso das medicações anti-retrovirais. Se no início da epidemia, a aids era caracterizada, sobretudo, pela magreza, hoje - tempos de "aids crônica"- estamos, uma vez mais, diante do estigma sobre o corpo, só que, paradoxalmente, com sinal trocado - o acúmulo "desordenado" de gordura no corpo. Este artigo apresenta e compara as mudanças corporais percebidas por pessoas que vivem com HIV e aids, ocorridas nos últimos anos da epidemia, com a utilização dos anti-retrovirais. Foram analisadas 32 entrevistas qualitativas com pessoas vivendo com HIV e aids, realizadas nos anos de 1999 e 2005. Ao nos depararmos com as novas questões emergentes e analisarmos sua interação com a crescente disponibilidade e utilização de tecnologias, fica a forte sensação de ressurgimento, sob nova forma, dos mesmos paradoxos previamente existentes nos tempos da aids aguda: o impacto dos sinais e um certo tipo de ressurgimento da desesperança quanto ao futuro de vida dessas pessoas.The Brazilian government has been providing free and universal access to the HAART therapy for people living with HIV and AIDS for ten years. Since then, many epidemiological characteristics have changed, and AIDS passed scientifically and medically to be classified as a chronic condition. This qualitative study aims to comprehend the challenges posed by self-perception of body changes experienced by people living with AIDS during recent years, as a result of prolonged use of antiretroviral medication.With this purpose, in 1999 and 2005, 32 semi-structured interviews with HIV positive individuals were held in the State of Sao Paulo to capture the challenges occurred during this period, in particular with regard to the lipodystrophy syndrome. The analysis of the data indicates that even with

  11. 'Checkmating HIV&AIDS': Using chess to break the silence in the classroom.

    Science.gov (United States)

    Esau, Omar

    2012-12-01

    In this article, I give an account of my 'Checkmating HIV&AIDS' action research project, which was an attempt to break the 'culture of silence' concerning HIV&AIDS and sex and sexuality in my classroom. In this project, I focused specifically on one code of sport, namely chess, and I point out and discuss the potential of using chess as an educational tool in addressing HIV&AIDS. It was found that learners enjoy playing chess and that it can be used in the Life Orientation classroom to promote HIV&AIDS awareness. This type of alternative awareness is relevant as learners in most schools were becoming fatigued by HIV&AIDS information overload. The project portrays the role of the teacher as a researcher and critical change agent in an HIV&AIDS-challenged society. PMID:23234377

  12. A New Time Measurement Method Using a High-End Global Navigation Satellite System to Analyze Alpine Skiing

    Science.gov (United States)

    Supej, Matej; Holmberg, Hans-Christer

    2011-01-01

    Accurate time measurement is essential to temporal analysis in sport. This study aimed to (a) develop a new method for time computation from surveyed trajectories using a high-end global navigation satellite system (GNSS), (b) validate its precision by comparing GNSS with photocells, and (c) examine whether gate-to-gate times can provide more…

  13. Navigation towards a goal position: from reactive to generalised learned control

    International Nuclear Information System (INIS)

    The task of navigating to a target position in space is a fairly common task for a mobile robot. It is desirable that this task is performed even in previously unknown environments. One reactive architecture explored before addresses this challenge by denning a hand-coded coordination of primitive behaviours, encoded by the Potential Fields method. Our first approach to improve the performance of this architecture adds a learning step to autonomously find the best way to coordinate primitive behaviours with respect to an arbitrary performance criterion. Because of the limitations presented by the Potential Fields method, especially in relation to non-convex obstacles, we are investigating the use of Relational Reinforcement Learning as a method to not only learn to act in the current environment, but also to generalise prior knowledge to the current environment in order to achieve the goal more quickly in a non-convex structured environment. We show the results of our previous efforts in reaching goal positions along with our current research on generalised approaches.

  14. Navigation towards a goal position: from reactive to generalised learned control

    Science.gov (United States)

    Freire da Silva, Valdinei; Henrique Selvatici, Antonio; Reali Costa, Anna Helena

    2011-03-01

    The task of navigating to a target position in space is a fairly common task for a mobile robot. It is desirable that this task is performed even in previously unknown environments. One reactive architecture explored before addresses this challenge by denning a hand-coded coordination of primitive behaviours, encoded by the Potential Fields method. Our first approach to improve the performance of this architecture adds a learning step to autonomously find the best way to coordinate primitive behaviours with respect to an arbitrary performance criterion. Because of the limitations presented by the Potential Fields method, especially in relation to non-convex obstacles, we are investigating the use of Relational Reinforcement Learning as a method to not only learn to act in the current environment, but also to generalise prior knowledge to the current environment in order to achieve the goal more quickly in a non-convex structured environment. We show the results of our previous efforts in reaching goal positions along with our current research on generalised approaches.

  15. A new bio-inspired perceptual control architecture applied to solving navigation tasks

    Science.gov (United States)

    Arena, P.; De Fiore, S.; Patané, L.; Vitanza, A.

    2009-05-01

    In this paper a new general purpose perceptual control architecture is presented and applied to robot navigation in cluttered environments. In nature, insects show the ability to react to certain stimuli with simple reflexes using direct sensory-motor pathways, which can be considered as basic behaviors, while high brain regions provide secondary pathway allowing the emergence of a cognitive behavior which modulates the basic abilities. Taking inspiration from this evidence, our architecture modulates, through a reinforcement learning, a set of competitive and concurrent basic behaviors in order to accomplish the task assigned through a reward function. The core of the architecture is constituted by the Representation layer, where different stimuli, triggering competitive reflexes, are fused to form a unique abstract picture of the environment. The representation is formalized by means of Reaction-Diffusion nonlinear partial differential equations, under the paradigm of the Cellular Neural Networks, whose dynamics converges to steady-state Turing patterns. A suitable unsupervised learning, introduced at the afferent (input) stage, leads to the shaping of the basins of attractions of the Turing patterns in order to incrementally drive the association between sensor stimuli and patterns. In this way, at the end of the leaning stage, each pattern is characteristic of a particular behavior modulation, while its trained basin of attraction contains the set of all the environment conditions, as recorded through the sensors, leading to the emergence of that particular behavior modulation. Robot simulations are reported to demonstrate the potentiality and the effectiveness of the approach.

  16. African-American culture and AIDS prevention. From barrier to ally.

    OpenAIRE

    Bowser, B P

    1992-01-01

    African Americans make up an increasing proportion of persons with the acquired immunodeficiency syndrome (AIDS). I identify and describe cultural elements such as oral traditions, multiple naming, a collective identity, extended families, and sexuality influenced by myth and exaggeration that condition African Americans' reactions to AIDS prevention. I also offer suggestions on how these cultural elements can be used for effective AIDS prevention efforts in African-American communities.

  17. On the terms of the recipient? Norwegian sports development aid to Tanzania in the 1980s

    OpenAIRE

    Straume, Solveig; Steen-Johnsen, Kari

    2010-01-01

    This article discusses the donor–recipient1 relationship in a sports development aid context, and identifies potential dilemmas occurring when aiming to give aid on the recipient’s terms. Using the case of the Norwegian sports development aid project Sport for All, it is argued that the Norwegian Confederation of Sports was clearly in control of the project throughout its various phases, and thus a contradiction between the discourse of equality and the actual practice was evid...

  18. A technique for simulating visual field losses in virtual environments to study human navigation.

    Science.gov (United States)

    Fortenbaugh, Francesca C; Hicks, John C; Hao, Lei; Turano, Kathleen A

    2007-08-01

    The following paper describes a new technique for simulating peripheral field losses in virtual environments to study the roles of the central and peripheral visual fields during navigation. Based on Geisler and Perry's (2002) gaze-contingent multiresolution display concept, the technique extends their methodology to work with three-dimensional images that are both transformed and rendered in real time by a computer graphics system. In order to assess the usefulness of this method for studying visual field losses, an experiment was run in which seven participants were required to walk to a target tree in a virtual forest as quickly and efficiently as possible while artificial head and eye-based delays were systematically introduced. Bilinear fits were applied to the mean trial times in order to assess at what delay lengths breaks in performance could be observed. Results suggest that breaks occur beyond the current delays inherent in the system. Increases in trial times across all delays tested were also observed when simulated peripheral field losses were applied compared to full FOV conditions. Possible applications and limitations of the system are discussed. The source code needed to program visual field losses can be found at lions.med.jhu.edu/archive/turanolab/Simulated_Visual_Field_Loss_Code.html. PMID:17958167

  19. Practical Strategies for Educating Nurses in India to Improve Care of Patients with HIV and AIDS

    OpenAIRE

    Baskaran, Christiana

    2014-01-01

    Background: Approximately 2.4 million people presently living in India have HIV/AIDS. Nurses have a vital role in the prevention and treatment of HIV/AIDS; therefore, education of nurses is imperative to manage HIV/AIDS in India. Very little information is available about nurses' knowledge in India. Purpose: The purpose of this study was to examine the effectiveness of a train-the-trainer (TTT) program in improving nurses' knowledge and assessing attitude about HIV/AIDS among nurses employed ...

  20. Cellular Nonlinear Networks for the emergence of perceptual states: application to robot navigation control.

    Science.gov (United States)

    Arena, Paolo; De Fiore, Sebastiano; Patané, Luca

    2009-01-01

    In this paper a new general purpose perceptual control architecture, based on nonlinear neural lattices, is presented and applied to solve robot navigation tasks. Insects show the ability to react to certain stimuli with simple reflexes, using direct sensory-motor pathways, which can be considered as basic behaviors, inherited and pre-wired. Relevant brain centres, known as Mushroom Bodies (MB) and Central Complex (CX) were recently identified in insects: though their functional details are not yet fully understood, it is known that they provide secondary pathways allowing the emergence of cognitive behaviors. These are gained through the coordination of the basic abilities to satisfy the insect's needs. Taking inspiration from this evidence, our architecture modulates, through a reinforcement learning, a set of competitive and concurrent basic behaviors in order to accomplish the task assigned through a reward function. The core of the architecture is constituted by the so-called Representation layer, used to create a concise picture of the current environment situation, fusing together different stimuli for the emergence of perceptual states. These perceptual states are steady state solutions of lattices of Reaction-Diffusion Cellular Nonlinear Networks (RD-CNN), designed to show Turing patterns. The exploitation of the dynamics of the multiple equilibria of the network is emphasized through the adaptive shaping of the basins of attraction for each emerged pattern. New experimental campaigns on standard robotic platforms are reported to demonstrate the potentiality and the effectiveness of the approach. PMID:19596552

  1. Navigation in endoscopic soft tissue surgery: perspectives and limitations.

    Science.gov (United States)

    Baumhauer, Matthias; Feuerstein, Marco; Meinzer, Hans-Peter; Rassweiler, J

    2008-04-01

    Despite rapid developments in the research areas of medical imaging, medical image processing, and robotics, the use of computer assistance in surgical routine is still limited to diagnostics, surgical planning, and interventions on mostly rigid structures. In order to establish a computer-aided workflow from diagnosis to surgical treatment and follow-up, several proposals for computer-assisted soft tissue interventions have been made in recent years. By means of different pre- and intraoperative information sources, such as surgical planning, intraoperative imaging, and tracking devices, surgical navigation systems aim to support surgeons in localizing anatomical targets, observing critical structures, and sparing healthy tissue. Current research in particular addresses the problem of organ shift and tissue deformation, and obstacles in communication between navigation system and surgeon. In this paper, we review computer-assisted navigation systems for soft tissue surgery. We concentrate on approaches that can be applied in endoscopic thoracic and abdominal surgery, because endoscopic surgery has special needs for image guidance due to limitations in perception. Furthermore, this paper informs the reader about new trends and technologies in the area of computer-assisted surgery. Finally, a balancing of the key challenges and possible benefits of endoscopic navigation refines the perspectives of this increasingly important discipline of computer-aided medical procedures. PMID:18366319

  2. Mobile Robot Navigation

    DEFF Research Database (Denmark)

    Andersen, Jens Christian

    2007-01-01

    . The research is now progressing towards autonomous robots which will be able to assist us in our daily life. One of the enabling technologies is navigation, and navigation is the subject of this thesis. Navigation of an autonomous robot is concerned with the ability of the robot to direct itself from...... validation of the implemented solutions and the ability of the methods to solve real world problems. The amount of software needed by an autonomous robot can be overwhelming. Software reuse and distributed development are therefore important issues. The thesis describes a new component architecture......Abstract Robots will soon take part in everyone’s daily life. In industrial production this has been the case for many years, but up to now the use of mobile robots has been limited to a few and isolated applications like lawn mowing, surveillance, agricultural production and military applications...

  3. Navigating Distributed Services

    DEFF Research Database (Denmark)

    Beute, Berco

    2002-01-01

    , to a situation where they are distributedacross the Internet. The second trend is the shift from a virtual environment that solelyconsists of distributed documents to a virtual environment that consists of bothdistributed documents and distributed services. The third and final trend is theincreasing...... diversity of devices used to access information on the Internet.The focal point of the thesis is an initial exploration of the effects of the trends onusers as they navigate the virtual environment of distributed documents and services.To begin the thesis uses scenarios as a heuristic device to identify and...... analyse themain effects of the trends. This is followed by an exploration of theory of navigationInformation Spaces, which is in turn followed by an overview of theories, and the stateof the art in navigating distributed services. These explorations of both theory andpractice resulted in a large number of...

  4. Using an inertial navigation algorithm and accelerometer to monitor chest compression depth during cardiopulmonary resuscitation.

    Science.gov (United States)

    Boussen, Salah; Ibouanga-Kipoutou, Harold; Fournier, Nathalie; Raboutet, Yves Godio; Llari, Maxime; Bruder, Nicolas; Arnoux, Pierre Jean; Behr, Michel

    2016-09-01

    We present an original method using a low cost accelerometer and a Kalman-filter based algorithm to monitor cardiopulmonary resuscitation chest compressions (CC) depth. A three-axis accelerometer connected to a computer was used during CC. A Kalman filter was used to retrieve speed and position from acceleration data. We first tested the algorithm for its accuracy and stability on surrogate data. The device was implemented for CC performed on a manikin. Different accelerometer locations were tested. We used a classical inertial navigation algorithm to reconstruct CPR depth and frequency. The device was found accurate enough to monitor CPR depth and its stability was checked for half an hour without any drift. Average error on displacement was ±0.5mm. We showed that depth measurement was dependent on the device location on the patient or the rescuer. The accuracy and stability of this small low-cost accelerometer coupled to a Kalman-filter based algorithm to reconstruct CC depth and frequency, was found well adapted and could be easily implemented. PMID:27246666

  5. ToGouR: Tour Guide Robot Visualization using Shape Recognition Pattern for Automatic Navigation

    Directory of Open Access Journals (Sweden)

    Hamzah Asyrani Bin Sulaiman

    2013-08-01

    Full Text Available The invention of autonomous robots with an increasing demand for industrial used has been caught attention from researchers and inventors. In this new sophisticated era, various types of robotsand systems have been developed and bring significant contribution to the industries, economy, and infrastructure. Thus in this project, we have develop an application for PIC based Tour Guide Robot (ToGouR where the PIC16F877A has been chosen as the main microcontroller. The application has a Graphical User Interface (GUI has allows the user to interact in interactive ways between ToGouR and the images for navigation systems. The application also has an ability to perform shape recognition for path planning and automatically make alternative ways when various shapes that have been recognized are put in the way. Various alternatives have been used to make sure this project is successful carried out. This tour guide robot is suitable to be commercialized with numerous robotics companies that would likecollaborate in delivering this project as a product and can be used for military or during any unexpected catastrophe such as one that occurred in Japan.

  6. From invagination to navigation: The story of magnetosome-associated proteins in magnetotactic bacteria.

    Science.gov (United States)

    Barber-Zucker, Shiran; Keren-Khadmy, Noa; Zarivach, Raz

    2016-02-01

    Magnetotactic bacteria (MTB) are a group of Gram-negative microorganisms that are able to sense and change their orientation in accordance with the geomagnetic field. This unique capability is due to the presence of a special suborganelle called the magnetosome, composed of either a magnetite or gregite crystal surrounded by a lipid membrane. MTB were first detected in 1975 and since then numerous efforts have been made to clarify the special mechanism of magnetosome formation at the molecular level. Magnetosome formation can be divided into several steps, beginning with vesicle invagination from the cell membrane, through protein sorting, followed by the combined steps of iron transportation, biomineralization, and the alignment of magnetosomes into a chain. The magnetosome-chain enables the sensing of the magnetic field, and thus, allows the MTB to navigate. It is known that magnetosome formation is tightly controlled by a distinctive set of magnetosome-associated proteins that are encoded mainly in a genomically conserved region within MTB called the magnetosome island (MAI). Most of these proteins were shown to have an impact on the magnetism of MTB. Here, we describe the process in which the magnetosome is formed with an emphasis on the different proteins that participate in each stage of the magnetosome formation scheme. PMID:26457474

  7. Application of high-precision two-way ranging to Galileo Earth-1 encounter navigation

    Science.gov (United States)

    Pollmeier, V. M.; Thurman, S. W.

    1992-01-01

    The application of precision two-way ranging to orbit determination with relatively short data arcs is investigated for the Galileo spacecraft's approach to its first Earth encounter (December 8, 1990). Analysis of previous S-band (2.3-GHz) ranging data acquired from Galileo indicated that under good signal conditions submeter precision and 10-m ranging accuracy were achieved. It is shown that ranging data of sufficient accuracy, when acquired from multiple stations, can sense the geocentric angular position of a distant spacecraft. A range data filtering technique, in which explicit modeling of range measurement bias parameters for each station pass is utilized, is shown to largely remove the systematic ground system calibration errors and transmission media effects from the Galileo range measurements, which would otherwise corrupt the angle-finding capabilities of the data. The accuracy of the Galileo orbit solutions obtained with S-band Doppler and precision ranging were found to be consistent with simple theoretical calculations, which predicted that angular accuracies of 0.26-0.34 microrad were achievable. In addition, the navigation accuracy achieved with precision ranging was marginally better than that obtained using delta-differenced one-way range (delta DOR), the principal data type that was previously used to obtain spacecraft angular position measurements operationally.

  8. Autonomous control for mechanically stable navigation of microscale implants in brain tissue to record neural activity.

    Science.gov (United States)

    Anand, Sindhu; Kumar, Swathy Sampath; Muthuswamy, Jit

    2016-08-01

    Emerging neural prosthetics require precise positional tuning and stable interfaces with single neurons for optimal function over a lifetime. In this study, we report an autonomous control to precisely navigate microscale electrodes in soft, viscoelastic brain tissue without visual feedback. The autonomous control optimizes signal-to-noise ratio (SNR) of single neuronal recordings in viscoelastic brain tissue while maintaining quasi-static mechanical stress conditions to improve stability of the implant-tissue interface. Force-displacement curves from microelectrodes in in vivo rodent experiments are used to estimate viscoelastic parameters of the brain. Using a combination of computational models and experiments, we determined an optimal movement for the microelectrodes with bidirectional displacements of 3:2 ratio between forward and backward displacements and a inter-movement interval of 40 s for minimizing mechanical stress in the surrounding brain tissue. A regulator with the above optimal bidirectional motion for the microelectrodes in in vivo experiments resulted in significant reduction in the number of microelectrode movements (0.23 movements/min) and longer periods of stable SNR (53 % of the time) compared to a regulator using a conventional linear, unidirectional microelectrode movement (with 1.48 movements/min and stable SNR 23 % of the time). PMID:27457752

  9. A HEURISTIC CASCADING FUZZY LOGIC APPROACH TO REACTIVE NAVIGATION FOR UAV

    Directory of Open Access Journals (Sweden)

    Yew-Chung Chak

    2014-12-01

    Full Text Available ABSTRACT: The capability of navigating Unmanned Aerial Vehicles (UAVs safely in unknown terrain offers huge potential for wider applications in non-segregated airspace. Flying in non-segregated airspace present a risk of collision with static obstacles (e.g., towers, power lines and moving obstacles (e.g., aircraft, balloons. In this work, we propose a heuristic cascading fuzzy logic control strategy to solve for the Conflict Detection and Resolution (CD&R problem, in which the control strategy is comprised of two cascading modules. The first one is Obstacle Avoidance control and the latter is Path Tracking control. Simulation results show that the proposed architecture effectively resolves the conflicts and achieve rapid movement towards the target waypoint.ABSTRAK: Keupayaan mengemudi Kenderaan Udara Tanpa Pemandu (UAV dengan selamat di kawasan yang tidak diketahui menawarkan potensi yang besar untuk aplikasi yang lebih luas dalam ruang udara yang tidak terasing. Terbang di ruang udara yang tidak terasing menimbulkan risiko perlanggaran dengan halangan statik (contohnya, menara, talian kuasa dan halangan bergerak (contohnya, pesawat udara, belon. Dalam kajian ini, kami mencadangkan satu strategi heuristik kawalan logik kabur yang melata untuk menyelesaikan masalah Pengesanan Konflik dan Penyelesaian (CD&R, di mana strategi kawalan yang terdiri daripada dua modul melata. Hasil simulasi menunjukkan bahawa seni bina yang dicadangkan berjaya menyelesaikan konflik dan mencapai penerbangan pesat ke arah titik laluan sasaran.KEYWORDS: fuzzy logic; motion planning; obstacle avoidance; path tracking; reactive navigation; UAV Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso

  10. Making a stronger case for comparative research to investigate the behavioral and neurological bases of three-dimensional navigation.

    Science.gov (United States)

    Nardi, Daniele; Bingman, Verner P

    2013-10-01

    The rich diversity of avian natural history provides exciting possibilities for comparative research aimed at understanding three-dimensional navigation. We propose some hypotheses relating differences in natural history to potential behavioral and neurological adaptations possessed by contrasting bird species. This comparative approach may offer unique insights into some of the important questions raised by Jeffery et al. PMID:24103612

  11. The development of a SAR dedicated navigation system: from scratch to the first test flight: 2004BU1-RE

    NARCIS (Netherlands)

    Lorga, J.F.M.; Rossum, W.L. van; Halsema, D. van; Chu, Q.P.; Mulder, J.A.

    2004-01-01

    In this paper, the authors propose to describe the development process of a navigation system, concerning Syntectic Aperture Radar (SAR) applications, starting from the motivation for the sensor selection and finalizing with the first flight-test results. Sensors selection was one of the first steps

  12. Perception-action map learning in controlled multiscroll systems applied to robot navigation.

    Science.gov (United States)

    Arena, Paolo; De Fiore, Sebastiano; Fortuna, Luigi; Patané, Luca

    2008-12-01

    In this paper a new technique for action-oriented perception in robots is presented. The paper starts from exploiting the successful implementation of the basic idea that perceptual states can be embedded into chaotic attractors whose dynamical evolution can be associated with sensorial stimuli. In this way, it can be possible to encode, into the chaotic dynamics, environment-dependent patterns. These have to be suitably linked to an action, executed by the robot, to fulfill an assigned mission. This task is addressed here: the action-oriented perception loop is closed by introducing a simple unsupervised learning stage, implemented via a bio-inspired structure based on the motor map paradigm. In this way, perceptual meanings, useful for solving a given task, can be autonomously learned, based on the environment-dependent patterns embedded into the controlled chaotic dynamics. The presented framework has been tested on a simulated robot and the performance have been successfully compared with other traditional navigation control paradigms. Moreover an implementation of the proposed architecture on a Field Programmable Gate Array is briefly outlined and preliminary experimental results on a roving robot are also reported. PMID:19123629

  13. An effective approach to improving low-cost GPS positioning accuracy in real-time navigation.

    Science.gov (United States)

    Islam, Md Rashedul; Kim, Jong-Myon

    2014-01-01

    Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previously estimated precious reference point, coordinate translation, and invalid data check also improve accuracy. In order to evaluate the performance of the proposed method, we conducted an experiment using a GARMIN GPS 19xHVS receiver attached to a car and used Google Maps to plot the processed data. The proposed method achieved improvement of 4-10 meters in several experiments. In addition, we compared the proposed approach with two other state-of-the-art methods: recursive averaging and ARMA interpolation. The experimental results show that the proposed approach outperforms other state-of-the-art methods in terms of positioning accuracy. PMID:25136679

  14. Perception-action map learning in controlled multiscroll systems applied to robot navigation

    Science.gov (United States)

    Arena, Paolo; De Fiore, Sebastiano; Fortuna, Luigi; Patané, Luca

    2008-12-01

    In this paper a new technique for action-oriented perception in robots is presented. The paper starts from exploiting the successful implementation of the basic idea that perceptual states can be embedded into chaotic attractors whose dynamical evolution can be associated with sensorial stimuli. In this way, it can be possible to encode, into the chaotic dynamics, environment-dependent patterns. These have to be suitably linked to an action, executed by the robot, to fulfill an assigned mission. This task is addressed here: the action-oriented perception loop is closed by introducing a simple unsupervised learning stage, implemented via a bio-inspired structure based on the motor map paradigm. In this way, perceptual meanings, useful for solving a given task, can be autonomously learned, based on the environment-dependent patterns embedded into the controlled chaotic dynamics. The presented framework has been tested on a simulated robot and the performance have been successfully compared with other traditional navigation control paradigms. Moreover an implementation of the proposed architecture on a Field Programmable Gate Array is briefly outlined and preliminary experimental results on a roving robot are also reported.

  15. 29 CFR Appendix V to Part 1918 - Basic Elements of a First Aid Training Program (Non-mandatory)

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Basic Elements of a First Aid Training Program (Non.... 1918, App. V Appendix V to Part 1918—Basic Elements of a First Aid Training Program (Non-mandatory... teaching first aid, and the recipients of first aid training. General Program Elements A. Teaching...

  16. Infrared spectroscopy: a novel tool to aid classification of DCIS

    Science.gov (United States)

    Subramanian, K.; Stone, N.; Kendall, C.; Brown, J. C.; McCarthy, K.; Bristol, J.; Chan, Y. H.

    2006-02-01

    There is no universally accepted grading system for the classification of Ductal Carcinoma in Situ (DCIS) although the diagnosis of DCIS has increased (2-20%) with screening mammography. (1) At present there are more than six different classifications and grading systems. Infrared spectroscopy is a non-invasive, rapid and specific technique used to analyse biological tissue. Spectral analysis of the chemical fingerprint within the duct would reveal spectral differences according to absorption and transmission characteristics of different grades of DCIS. An existing model of histopathological classification which is locally accepted has been tested and evaluated in this study. 19 ducts from different biopsy specimens were marked on H&E stained sections by two breast pathologists, according to the locally accepted classification. A consecutive unstained 20μm section was subjected to infrared analysis (Perkin-Elmer). Principal component analysis was undertaken using Matlab. Pseudocolor maps of the principal component scores delineated morphological features of the ducts. Peaks in the corresponding principal component loads were identified to enable understanding of the biochemical changes associated with different grades of DCIS. A 4-group cross-validated classification model was developed using multivariate statistical analysis with selected spectra from different grades of DCIS. The classification model demonstrated good separation of the different grades of the DCIS with a sensitivity of 80-99% and specificity of 92-98%. Infrared spectroscopy is a highly sensitive and specific technique for the demonstration of biochemical changes within the proliferative duct. It could aid in reclassifying the grades of DCIS in accordance with the biochemical and morphological changes that occur with proliferation. Infrared spectroscopy has potential as an added tool for the pathologist to diagnose in vitro.

  17. The attack navigator

    DEFF Research Database (Denmark)

    Probst, Christian W.; Willemson, Jan; Pieters, Wolter

    2016-01-01

    The need to assess security and take protection decisions is at least as old as our civilisation. However, the complexity and development speed of our interconnected technical systems have surpassed our capacity to imagine and evaluate risk scenarios. This holds in particular for risks that are...... caused by the strategic behaviour of adversaries. Therefore, technology-supported methods are needed to help us identify and manage these risks. In this paper, we describe the attack navigator: a graph-based approach to security risk assessment inspired by navigation systems. Based on maps of a socio...

  18. Shooting the Rapids: Navigating Transitions to Adaptive Governance of Social-Ecological Systems

    Directory of Open Access Journals (Sweden)

    Carl Folke

    2006-06-01

    Full Text Available The case studies of Kristianstads Vattenrike, Sweden; the Northern Highlands Lake District and the Everglades in the USA; the Mae Nam Ping Basin, Thailand; and the Goulburn-Broken Catchment, Australia, were compared to assess the outcome of different actions for transforming social-ecological systems (SESs. The transformations consisted of two phases, a preparation phase and a transition phase, linked by a window of opportunity. Key leaders and shadow networks can prepare a system for change by exploring alternative system configurations and developing strategies for choosing from among possible futures. Key leaders can recognize and use or create windows of opportunity and navigate transitions toward adaptive governance. Leadership functions include the ability to span scales of governance, orchestrate networks, integrate and communicate understanding, and reconcile different problem domains. Successful transformations rely on epistemic and shadow networks to provide novel ideas and ways of governing SESs. We conclude by listing some 𔄬rules of thumb” that can help build leadership and networks for successful transformations toward adaptive governance of social-ecological systems.

  19. Splinter, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Splinter, First Aid A A A First Aid for Splinter: View ... wet, it makes the area prone to infection. First Aid Guide Self-care measures to remove a splinter ...

  20. 75 FR 42749 - Fidelity National Financial, Inc.; Analysis of the Agreement Containing Consent Order to Aid...

    Science.gov (United States)

    2010-07-22

    ... Fidelity National Financial, Inc.; Analysis of the Agreement Containing Consent Order to Aid Public Comment... or unfair methods of competition. The attached Analysis to Aid Public Comment describes both the.... Comments should refer to ``Fidelity National Financial, File No. 091 0032'' to facilitate the...