Mission Analysis, Operations, and Navigation Toolkit Environment (Monte) Version 040
Sunseri, Richard F.; Wu, Hsi-Cheng; Evans, Scott E.; Evans, James R.; Drain, Theodore R.; Guevara, Michelle M.
2012-01-01
Monte is a software set designed for use in mission design and spacecraft navigation operations. The system can process measurement data, design optimal trajectories and maneuvers, and do orbit determination, all in one application. For the first time, a single software set can be used for mission design and navigation operations. This eliminates problems due to different models and fidelities used in legacy mission design and navigation software. The unique features of Monte 040 include a blowdown thruster model for GRAIL (Gravity Recovery and Interior Laboratory) with associated pressure models, as well as an updated, optimalsearch capability (COSMIC) that facilitated mission design for ARTEMIS. Existing legacy software lacked the capabilities necessary for these two missions. There is also a mean orbital element propagator and an osculating to mean element converter that allows long-term orbital stability analysis for the first time in compiled code. The optimized trajectory search tool COSMIC allows users to place constraints and controls on their searches without any restrictions. Constraints may be user-defined and depend on trajectory information either forward or backwards in time. In addition, a long-term orbit stability analysis tool (morbiter) existed previously as a set of scripts on top of Monte. Monte is becoming the primary tool for navigation operations, a core competency at JPL. The mission design capabilities in Monte are becoming mature enough for use in project proposals as well as post-phase A mission design. Monte has three distinct advantages over existing software. First, it is being developed in a modern paradigm: object- oriented C++ and Python. Second, the software has been developed as a toolkit, which allows users to customize their own applications and allows the development team to implement requirements quickly, efficiently, and with minimal bugs. Finally, the software is managed in accordance with the CMMI (Capability Maturity Model
2008-09-01
This industry survey documents the symbols for navigation aids, airports, lines, and linear patterns currently in use by avionics manufactureres and chart providers for depicting aeronautical charting information. Nine avionics display manufacturers ...
Linear Look-ahead in Conjunctive Cells: An Entorhinal Mechanism for Vector-Based Navigation
John L Kubie
2012-04-01
Full Text Available The crisp organization of the firing bumps of entorhinal grid cells and conjunctive cells leads to the notion that the entorhinal cortex may compute linear navigation routes. Specifically, we propose a process, termed linear look-ahead, by which a stationary animal could compute a series of locations in the direction it is facing. We speculate that this computation could be achieved through learned patterns of connection strengths among entorhinal neurons. This paper has three sections. First, we describe the minimal grid cell properties that will be built into our network. Specifically, the network relies of rigid modules of neurons, where all members have identical grid scale and orientation, but differ in spatial phase. Additionally, these neurons must be densely interconnected with synapses that are modifiable early in the animal’s life. Second, we investigate whether plasticity during short bouts of locomotion could induce patterns of connections amongst grid cells or conjunctive cells. Finally, we run a simulation to test whether the learned connection patterns can exhibit linear look-ahead. Our results are straightforward. A simulated 30-minute walk produces weak strengthening of synapses between grid cells that do not support linear look-ahead. Similar training in a conjunctive-cell module produces a small subset of very strong connections between cells. These strong pairs have three properties: The pre- and post-synaptic cells have similar heading direction. The cell pairs have neighboring grid bumps. Finally, the spatial offset of firing bumps of the cell pair is in the direction of the common heading preference. Such a module can produce strong and accurate linear look ahead starting in any location and extending in any direction. We speculate that this process may: 1. compute linear paths to goals; 2. update grid cell firing during navigation; and 3. stabilize the rigid modules of grid cells and conjunctive cells.
IceBridge GPS L0 Raw Satellite Navigation Data, Version 1
National Aeronautics and Space Administration — The NASA IceBridge GPS L0 Raw Satellite Navigation Data (IPUTG0) data set contains GPS readings, including latitude, longitude, track, ground speed, off distance,...
ORACLS- OPTIMAL REGULATOR ALGORITHMS FOR THE CONTROL OF LINEAR SYSTEMS (DEC VAX VERSION)
Frisch, H.
1994-01-01
computations: the eigenvalues and eigenvectors of real matrices; the relative stability of a given matrix; matrix factorization; the solution of linear constant coefficient vector-matrix algebraic equations; the controllability properties of a linear time-invariant system; the steady-state covariance matrix of an open-loop stable system forced by white noise; and the transient response of continuous linear time-invariant systems. The control law design routines of ORACLS implement some of the more common techniques of time-invariant LQG methodology. For the finite-duration optimal linear regulator problem with noise-free measurements, continuous dynamics, and integral performance index, a routine is provided which implements the negative exponential method for finding both the transient and steady-state solutions to the matrix Riccati equation. For the discrete version of this problem, the method of backwards differencing is applied to find the solutions to the discrete Riccati equation. A routine is also included to solve the steady-state Riccati equation by the Newton algorithms described by Klein, for continuous problems, and by Hewer, for discrete problems. Another routine calculates the prefilter gain to eliminate control state cross-product terms in the quadratic performance index and the weighting matrices for the sampled data optimal linear regulator problem. For cases with measurement noise, duality theory and optimal regulator algorithms are used to calculate solutions to the continuous and discrete Kalman-Bucy filter problems. Finally, routines are included to implement the continuous and discrete forms of the explicit (model-in-the-system) and implicit (model-in-the-performance-index) model following theory. These routines generate linear control laws which cause the output of a dynamic time-invariant system to track the output of a prescribed model. In order to apply ORACLS, the user must write an executive (driver) program which inputs the problem coefficients
ORACLS- OPTIMAL REGULATOR ALGORITHMS FOR THE CONTROL OF LINEAR SYSTEMS (CDC VERSION)
Armstrong, E. S.
1994-01-01
computations: the eigenvalues and eigenvectors of real matrices; the relative stability of a given matrix; matrix factorization; the solution of linear constant coefficient vector-matrix algebraic equations; the controllability properties of a linear time-invariant system; the steady-state covariance matrix of an open-loop stable system forced by white noise; and the transient response of continuous linear time-invariant systems. The control law design routines of ORACLS implement some of the more common techniques of time-invariant LQG methodology. For the finite-duration optimal linear regulator problem with noise-free measurements, continuous dynamics, and integral performance index, a routine is provided which implements the negative exponential method for finding both the transient and steady-state solutions to the matrix Riccati equation. For the discrete version of this problem, the method of backwards differencing is applied to find the solutions to the discrete Riccati equation. A routine is also included to solve the steady-state Riccati equation by the Newton algorithms described by Klein, for continuous problems, and by Hewer, for discrete problems. Another routine calculates the prefilter gain to eliminate control state cross-product terms in the quadratic performance index and the weighting matrices for the sampled data optimal linear regulator problem. For cases with measurement noise, duality theory and optimal regulator algorithms are used to calculate solutions to the continuous and discrete Kalman-Bucy filter problems. Finally, routines are included to implement the continuous and discrete forms of the explicit (model-in-the-system) and implicit (model-in-the-performance-index) model following theory. These routines generate linear control laws which cause the output of a dynamic time-invariant system to track the output of a prescribed model. In order to apply ORACLS, the user must write an executive (driver) program which inputs the problem coefficients
Cullen, D.E.
1979-01-01
Program LINEAR converts evaluated cross sections in the ENDF/B format into a tabular form that is subject to linear-linear interpolation in energy and cross section. The code also thins tables of cross sections already in that form (i.e., removes points not needed for linear interpolability). The main advantage of the code is that it allows subsequent codes to consider only linear-linear data. A listing of the source deck is available on request
A linear process-algebraic format for probabilistic systems with data (extended version)
Katoen, Joost P.; van de Pol, Jan Cornelis; Stoelinga, Mariëlle Ida Antoinette; Timmer, Mark
2010-01-01
This paper presents a novel linear process-algebraic format for probabilistic automata. The key ingredient is a symbolic transformation of probabilistic process algebra terms that incorporate data into this linear format while preserving strong probabilistic bisimulation. This generalises similar
Lothes, Thomas Ernst; Siekmann, Max; König, Ralph Werner; Wirtz, Christian Rainer; Coburger, Jan
2016-11-01
Background Intraoperative imaging in low-grade glioma (LGG) surgery can facilitate residual tumor control and improve surgical outcome. The aim of the study was to evaluate the ideal application and typical interactions of intraoperative MRI (iMRI), conventional low-frequency intraoperative ultrasound (cioUS), and high-frequency linear array intraoperative ultrasound (lioUS) to optimize surgical workflow. Methods Prospectively, we included 11 patients with an LGG. Typical procedural workflow in the iMRI suite was recorded with a compatible software. We took notes of duration, frequency of application, the surgeon's evaluation of image quality, and the respective benefit of lioUS (15 MHz), cioUS (7 MHz), and iMRI (1.5 T). With the help of the workflow software, we meticulously analyzed ∼ 55 hours of surgery. Results During the interventions, lioUS was used more often (76.3%) than cioUS (23.7%) and showed a better mean image quality (1 = best to 6 = worst) of 2.08 versus 3.26 with cioUS. The benefit of the lioUS application was rated with an average of 2.27, whereas the cioUS probe only reached a mean value of 3.83. The most common application of lioUS was resection control (42.6%); cioUS was used mainly for orientation (63.2%). Overall, lioUS was used more often and was rated better for both the purposes just described regarding image quality and benefit. Estimated residual tumor based on lioUS alone was lower than the final residual tumor detected with iMRI (7.5% versus 14.5%). The latter technique was rated as the best imaging modality for resection control in all cases followed by lioUS. Conclusion We provide proof of principle for workflow assessment in cranial neurosurgery. Although iMRI remains the imaging method of choice, lioUS has shown to be beneficial in a combined setup. Evaluation of lioUS was significantly superior to cioUS in most indications except for subcortical lesions. Georg Thieme Verlag KG Stuttgart · New York.
User's Guide to the Weighted-Multiple-Linear Regression Program (WREG version 1.0)
Eng, Ken; Chen, Yin-Yu; Kiang, Julie.E.
2009-01-01
Streamflow is not measured at every location in a stream network. Yet hydrologists, State and local agencies, and the general public still seek to know streamflow characteristics, such as mean annual flow or flood flows with different exceedance probabilities, at ungaged basins. The goals of this guide are to introduce and familiarize the user with the weighted multiple-linear regression (WREG) program, and to also provide the theoretical background for program features. The program is intended to be used to develop a regional estimation equation for streamflow characteristics that can be applied at an ungaged basin, or to improve the corresponding estimate at continuous-record streamflow gages with short records. The regional estimation equation results from a multiple-linear regression that relates the observable basin characteristics, such as drainage area, to streamflow characteristics.
Comments on a time-dependent version of the linear-quadratic model
Tucker, S.L.; Travis, E.L.
1990-01-01
The accuracy and interpretation of the 'LQ + time' model are discussed. Evidence is presented, based on data in the literature, that this model does not accurately describe the changes in isoeffect dose occurring with protraction of the overall treatment time during fractionated irradiation of the lung. This lack of fit of the model explains, in part, the surprisingly large values of γ/α that have been derived from experimental lung data. The large apparent time factors for lung suggested by the model are also partly explained by the fact that γT/α, despite having units of dose, actually measures the influence of treatment time on the effect scale, not the dose scale, and is shown to consistently overestimate the change in total dose. The unusually high values of α/β that have been derived for lung using the model are shown to be influenced by the method by which the model was fitted to data. Reanalyses of the data using a more statistically valid regression procedure produce estimates of α/β more typical of those usually cited for lung. Most importantly, published isoeffect data from lung indicate that the true deviation from the linear-quadratic (LQ) model is nonlinear in time, instead of linear, and also depends on other factors such as the effect level and the size of dose per fraction. Thus, the authors do not advocate the use of the 'LQ + time' expression as a general isoeffect model. (author). 32 refs.; 3 figs.; 1 tab
Jean-Pierre, Pascal; Fiscella, Kevin; Winters, Paul C; Paskett, Electra; Wells, Kristen; Battaglia, Tracy
2012-09-01
Patient satisfaction (PS), a key measure of quality of cancer care, is a core study outcome of the multi-site National Cancer Institute-funded Patient Navigation Research Program. Despite large numbers of underserved monolingual Spanish speakers (MSS) residing in USA, there is no validated Spanish measure of PS that spans the whole spectrum of cancer-related care. The present study reports on the validation of the Patient Satisfaction with Cancer Care (PSCC) measure for Spanish (PSCC-Sp) speakers receiving diagnostic and therapeutic cancer-related care. Original PSCC items were professionally translated and back translated to ensure cultural appropriateness, meaningfulness, and equivalence. Then, the resulting 18-item PSCC-Sp measure was administered to 285 MSS. We evaluated latent structure and internal consistency of the PSCC-Sp using principal components analysis (PCA) and Cronbach coefficient alpha (α). We used correlation analyses to demonstrate divergence and convergence of the PSCC-Sp with a Spanish version of the Patient Satisfaction with Interpersonal Relationship with Navigator (PSN-I-Sp) measure and patients' demographics. The PCA revealed a coherent set of items that explicates 47% of the variance in PS. Reliability assessment demonstrated that the PSCC-Sp had high internal consistency (α = 0.92). The PSCC-Sp demonstrated good face validity and convergent and divergent validities as indicated by moderate correlations with the PSN-I-Sp (p = 0.003) and nonsignificant correlations with marital status and household income (all p(s) > 0.05). The PSCC-Sp is a valid and reliable measure of PS and should be tested in other MSS populations.
Kinjo, Ken; Uchibe, Eiji; Doya, Kenji
2013-01-01
Linearly solvable Markov Decision Process (LMDP) is a class of optimal control problem in which the Bellman's equation can be converted into a linear equation by an exponential transformation of the state value function (Todorov, 2009b). In an LMDP, the optimal value function and the corresponding control policy are obtained by solving an eigenvalue problem in a discrete state space or an eigenfunction problem in a continuous state using the knowledge of the system dynamics and the action, state, and terminal cost functions. In this study, we evaluate the effectiveness of the LMDP framework in real robot control, in which the dynamics of the body and the environment have to be learned from experience. We first perform a simulation study of a pole swing-up task to evaluate the effect of the accuracy of the learned dynamics model on the derived the action policy. The result shows that a crude linear approximation of the non-linear dynamics can still allow solution of the task, despite with a higher total cost. We then perform real robot experiments of a battery-catching task using our Spring Dog mobile robot platform. The state is given by the position and the size of a battery in its camera view and two neck joint angles. The action is the velocities of two wheels, while the neck joints were controlled by a visual servo controller. We test linear and bilinear dynamic models in tasks with quadratic and Guassian state cost functions. In the quadratic cost task, the LMDP controller derived from a learned linear dynamics model performed equivalently with the optimal linear quadratic regulator (LQR). In the non-quadratic task, the LMDP controller with a linear dynamics model showed the best performance. The results demonstrate the usefulness of the LMDP framework in real robot control even when simple linear models are used for dynamics learning.
Ken eKinjo
2013-04-01
Full Text Available Linearly solvable Markov Decision Process (LMDP is a class of optimal control problem in whichthe Bellman’s equation can be converted into a linear equation by an exponential transformation ofthe state value function (Todorov, 2009. In an LMDP, the optimal value function and the correspondingcontrol policy are obtained by solving an eigenvalue problem in a discrete state space or an eigenfunctionproblem in a continuous state using the knowledge of the system dynamics and the action, state, andterminal cost functions.In this study, we evaluate the effectiveness of the LMDP framework in real robot control, in whichthe dynamics of the body and the environment have to be learned from experience. We first perform asimulation study of a pole swing-up task to evaluate the effect of the accuracy of the learned dynam-ics model on the derived the action policy. The result shows that a crude linear approximation of thenonlinear dynamics can still allow solution of the task, despite with a higher total cost.We then perform real robot experiments of a battery-catching task using our Spring Dog mobile robotplatform. The state is given by the position and the size of a battery in its camera view and two neck jointangles. The action is the velocities of two wheels, while the neck joints were controlled by a visual servocontroller. We test linear and bilinear dynamic models in tasks with quadratic and Guassian state costfunctions. In the quadratic cost task, the LMDP controller derived from a learned linear dynamics modelperformed equivalently with the optimal linear quadratic controller (LQR. In the non-quadratic task, theLMDP controller with a linear dynamics model showed the best performance. The results demonstratethe usefulness of the LMDP framework in real robot control even when simple linear models are usedfor dynamics learning.
Patricia K. Lebow; Henry Spelter; Peter J. Ince
2003-01-01
This report provides documentation and user information for FPL-PELPS, a personal computer price endogenous linear programming system for economic modeling. Originally developed to model the North American pulp and paper industry, FPL-PELPS follows its predecessors in allowing the modeling of any appropriate sector to predict consumption, production and capacity by...
Scaling versus asymptotic scaling in the non-linear σ-model in 2D. Continuum version
Flyvbjerg, H.
1990-01-01
The two-point function of the O(N)-symmetric non-linear σ-model in two dimensions is large-N expanded and renormalized, neglecting terms of O(1/N 2 ). At finite cut-off, universal, analytical expressions relate the magnetic susceptibility and the dressed mass to the bare coupling. Removing the cut-off, a similar relation gives the renormalized coupling as a function of the mass gap. In the weak-coupling limit these relations reproduce the results of renormalization group improved weak-coupling perturbation theory to two-loop order. The constant left unknown, when the renormalization group is integrated, is determined here. The approach to asymptotic scaling is studied for various values of N. (orig.)
Optimal motion planning using navigation measure
Vaidya, Umesh
2018-05-01
We introduce navigation measure as a new tool to solve the motion planning problem in the presence of static obstacles. Existence of navigation measure guarantees collision-free convergence at the final destination set beginning with almost every initial condition with respect to the Lebesgue measure. Navigation measure can be viewed as a dual to the navigation function. While the navigation function has its minimum at the final destination set and peaks at the obstacle set, navigation measure takes the maximum value at the destination set and is zero at the obstacle set. A linear programming formalism is proposed for the construction of navigation measure. Set-oriented numerical methods are utilised to obtain finite dimensional approximation of this navigation measure. Application of the proposed navigation measure-based theoretical and computational framework is demonstrated for a motion planning problem in a complex fluid flow.
Simon, M; Evans, S.; McAloone, Timothy Charles
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...
Azarmehr, Iman; Stokbro, Kasper; Bell, R. Bryan
2017-01-01
Purpose: This systematic review investigates the most common indications, treatments, and outcomes of surgical navigation (SN) published from 2010 to 2015. The evolution of SN and its application in oral and maxillofacial surgery have rapidly developed over recent years, and therapeutic indicatio...
Kuhlmann, Stefan; Edler, Jakob; Ordonez Matamoros, Hector Gonzalo; Randles, Sally; Walhout, Bart; Walhout, Bart; Gough, Clair; Lindner, Ralf; Lindner, Ralf; Kuhlmann, Stefan; Randles, Sally; Bedsted, Bjorn; Gorgoni, Guido; Griessler, Erich; Loconto, Allison; Mejlgaard, Niels
2016-01-01
Research and innovation activities need to become more responsive to societal challenges and concerns. The Responsibility Navigator, developed in the Res-AGorA project, supports decision-makers to govern such activities towards more conscious responsibility. What is considered “responsible” will
Cesarone, R. J.; Burke, J. D.; Hastrup, R. C.; Lo, M. W.
2003-01-01
In the future, navigation and communication in Earth-Moon space and on the Moon will differ from past practice due to evolving technology and new requirements. Here we describe likely requirements, discuss options for meeting them, and advocate steps that can be taken now to begin building the navcom systems needed in coming years for exploring and using the moon.
Usability Testing of Two Ambulatory EHR Navigators.
Hultman, Gretchen; Marquard, Jenna; Arsoniadis, Elliot; Mink, Pamela; Rizvi, Rubina; Ramer, Tim; Khairat, Saif; Fickau, Keri; Melton, Genevieve B
2016-01-01
Despite widespread electronic health record (EHR) adoption, poor EHR system usability continues to be a significant barrier to effective system use for end users. One key to addressing usability problems is to employ user testing and user-centered design. To understand if redesigning an EHR-based navigation tool with clinician input improved user performance and satisfaction. A usability evaluation was conducted to compare two versions of a redesigned ambulatory navigator. Participants completed tasks for five patient cases using the navigators, while employing a think-aloud protocol. The tasks were based on Meaningful Use (MU) requirements. The version of navigator did not affect perceived workload, and time to complete tasks was longer in the redesigned navigator. A relatively small portion of navigator content was used to complete the MU-related tasks, though navigation patterns were highly variable across participants for both navigators. Preferences for EHR navigation structures appeared to be individualized. This study demonstrates the importance of EHR usability assessments to evaluate group and individual performance of different interfaces and preferences for each design.
Siekmann, Max; Lothes, Thomas; König, Ralph; Wirtz, Christian Rainer; Coburger, Jan
2018-03-01
Currently, intraoperative ultrasound in brain tumor surgery is a rapidly propagating option in imaging technology. We examined the accuracy and resolution limits of different ultrasound probes and the influence of 3D-reconstruction in a phantom and compared these results to MRI in an intraoperative setting (iMRI). An agarose gel phantom with predefined gel targets was examined with iMRI, a sector (SUS) and a linear (LUS) array probe with two-dimensional images. Additionally, 3D-reconstructed sweeps in perpendicular directions were made of every target with both probes, resulting in 392 measurements. Statistical calculations were performed, and comparative boxplots were generated. Every measurement of iMRI and LUS was more precise than SUS, while there was no apparent difference in height of iMRI and 3D-reconstructed LUS. Measurements with 3D-reconstructed LUS were always more accurate than in 2D-LUS, while 3D-reconstruction of SUS showed nearly no differences to 2D-SUS in some measurements. We found correlations of 3D-reconstructed SUS and LUS length and width measurements with 2D results in the same image orientation. LUS provides an accuracy and resolution comparable to iMRI, while SUS is less exact than LUS and iMRI. 3D-reconstruction showed the potential to distinctly improve accuracy and resolution of ultrasound images, although there is a strong correlation with the sweep direction during data acquisition.
Dörsek, Philipp; Melenk, Jens M.
2017-01-01
We consider the extension of the p-robust equilibrated error estimator due to Braess, Pillwein and Schöberl to linear elasticity. We derive a formulation where the local mixed auxiliary problems do not require symmetry of the stresses. The resulting error estimator is p-robust, and the reliability estimate is also robust in the incompressible limit if quadratics are included in the approximation space. Extensions to other systems of linear second-order partial differential equations are discu...
Comprehension and navigation of networked hypertexts
Blom, Helen; Segers, Eliane; Knoors, Harry; Hermans, Daan; Verhoeven, Ludo
2018-01-01
This study aims to investigate secondary school students' reading comprehension and navigation of networked hypertexts with and without a graphic overview compared to linear digital texts. Additionally, it was studied whether prior knowledge, vocabulary, verbal, and visual working memory moderated
Linearization of the Lorenz system
Li, Chunbiao; Sprott, Julien Clinton; Thio, Wesley
2015-01-01
A partial and complete piecewise linearized version of the Lorenz system is proposed. The linearized versions have an independent total amplitude control parameter. Additional further linearization leads naturally to a piecewise linear version of the diffusionless Lorenz system. A chaotic circuit with a single amplitude controller is then implemented using a new switch element, producing a chaotic oscillation that agrees with the numerical calculation for the piecewise linear diffusionless Lorenz system. - Highlights: • A partial and complete piecewise linearized version of the Lorenz system are addressed. • The linearized versions have an independent total amplitude control parameter. • A piecewise linear version of the diffusionless Lorenz system is derived by further linearization. • A corresponding chaotic circuit without any multiplier is implemented for the chaotic oscillation
Linearization of the Lorenz system
Li, Chunbiao, E-mail: goontry@126.com [School of Electronic & Information Engineering, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Engineering Technology Research and Development Center of Jiangsu Circulation Modernization Sensor Network, Jiangsu Institute of Commerce, Nanjing 211168 (China); Sprott, Julien Clinton [Department of Physics, University of Wisconsin–Madison, Madison, WI 53706 (United States); Thio, Wesley [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH 43210 (United States)
2015-05-08
A partial and complete piecewise linearized version of the Lorenz system is proposed. The linearized versions have an independent total amplitude control parameter. Additional further linearization leads naturally to a piecewise linear version of the diffusionless Lorenz system. A chaotic circuit with a single amplitude controller is then implemented using a new switch element, producing a chaotic oscillation that agrees with the numerical calculation for the piecewise linear diffusionless Lorenz system. - Highlights: • A partial and complete piecewise linearized version of the Lorenz system are addressed. • The linearized versions have an independent total amplitude control parameter. • A piecewise linear version of the diffusionless Lorenz system is derived by further linearization. • A corresponding chaotic circuit without any multiplier is implemented for the chaotic oscillation.
Navigation Lights - USACE IENC
Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...
Ahlfeld, D.P.; Dougherty, D.E.
1994-11-01
MODLP is a computational tool that may help design capture zones for controlling the movement of contaminated groundwater. It creates and solves linear optimization programs that contain constraints on hydraulic head or head differences in a groundwater system. The groundwater domain is represented by USGS MODFLOW groundwater flow simulation model. This document describes the general structure of the computer program, MODLP, the types of constraints that may be imposed, detailed input instructions, interpretation of the output, and the interaction with the MODFLOW simulation kernel
Waddell, Lucas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Muldoon, Frank [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Henry, Stephen Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hoffman, Matthew John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zwerneman, April Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Backlund, Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Melander, Darryl J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lawton, Craig R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rice, Roy Eugene [Teledyne Brown Engineering, Huntsville, AL (United States)
2017-09-01
In order to effectively plan the management and modernization of their large and diverse fleets of vehicles, Program Executive Office Ground Combat Systems (PEO GCS) and Program Executive Office Combat Support and Combat Service Support (PEO CS&CSS) commis- sioned the development of a large-scale portfolio planning optimization tool. This software, the Capability Portfolio Analysis Tool (CPAT), creates a detailed schedule that optimally prioritizes the modernization or replacement of vehicles within the fleet - respecting numerous business rules associated with fleet structure, budgets, industrial base, research and testing, etc., while maximizing overall fleet performance through time. This paper contains a thor- ough documentation of the terminology, parameters, variables, and constraints that comprise the fleet management mixed integer linear programming (MILP) mathematical formulation. This paper, which is an update to the original CPAT formulation document published in 2015 (SAND2015-3487), covers the formulation of important new CPAT features.
Towards Safe Navigation by Formalizing Navigation Rules
Arne Kreutzmann
2013-06-01
Full Text Available One crucial aspect of safe navigation is to obey all navigation regulations applicable, in particular the collision regulations issued by the International Maritime Organization (IMO Colregs. Therefore, decision support systems for navigation need to respect Colregs and this feature should be verifiably correct. We tackle compliancy of navigation regulations from a perspective of software verification. One common approach is to use formal logic, but it requires to bridge a wide gap between navigation concepts and simple logic. We introduce a novel domain specification language based on a spatio-temporal logic that allows us to overcome this gap. We are able to capture complex navigation concepts in an easily comprehensible representation that can direcly be utilized by various bridge systems and that allows for software verification.
Lawson, C. L.; Krogh, F. T.; Gold, S. S.; Kincaid, D. R.; Sullivan, J.; Williams, E.; Hanson, R. J.; Haskell, K.; Dongarra, J.; Moler, C. B.
1982-01-01
The Basic Linear Algebra Subprograms (BLAS) library is a collection of 38 FORTRAN-callable routines for performing basic operations of numerical linear algebra. BLAS library is portable and efficient source of basic operations for designers of programs involving linear algebriac computations. BLAS library is supplied in portable FORTRAN and Assembler code versions for IBM 370, UNIVAC 1100 and CDC 6000 series computers.
Loeliger, Jon
2012-01-01
Get up to speed on Git for tracking, branching, merging, and managing code revisions. Through a series of step-by-step tutorials, this practical guide takes you quickly from Git fundamentals to advanced techniques, and provides friendly yet rigorous advice for navigating the many functions of this open source version control system. This thoroughly revised edition also includes tips for manipulating trees, extended coverage of the reflog and stash, and a complete introduction to the GitHub repository. Git lets you manage code development in a virtually endless variety of ways, once you understand how to harness the system's flexibility. This book shows you how. Learn how to use Git for several real-world development scenarios ; Gain insight into Git's common-use cases, initial tasks, and basic functions ; Use the system for both centralized and distributed version control ; Learn how to manage merges, conflicts, patches, and diffs ; Apply advanced techniques such as rebasing, hooks, and ways to handle submodu...
Sidwell, Kenneth W.; Baruah, Pranab K.; Bussoletti, John E.; Medan, Richard T.; Conner, R. S.; Purdon, David J.
1990-01-01
A comprehensive description of user problem definition for the PAN AIR (Panel Aerodynamics) system is given. PAN AIR solves the 3-D linear integral equations of subsonic and supersonic flow. Influence coefficient methods are used which employ source and doublet panels as boundary surfaces. Both analysis and design boundary conditions can be used. This User's Manual describes the information needed to use the PAN AIR system. The structure and organization of PAN AIR are described, including the job control and module execution control languages for execution of the program system. The engineering input data are described, including the mathematical and physical modeling requirements. Version 3.0 strictly applies only to PAN AIR version 3.0. The major revisions include: (1) inputs and guidelines for the new FDP module (which calculates streamlines and offbody points); (2) nine new class 1 and class 2 boundary conditions to cover commonly used modeling practices, in particular the vorticity matching Kutta condition; (3) use of the CRAY solid state Storage Device (SSD); and (4) incorporation of errata and typo's together with additional explanation and guidelines.
Emily Olorin
2015-08-01
Full Text Available Short linear motifs (SLiMs are small protein sequence patterns that mediate a large number of critical protein-protein interactions, involved in processes such as complex formation, signal transduction, localisation and stabilisation. SLiMs show rapid evolutionary dynamics and are frequently the targets of molecular mimicry by pathogens. Identifying enriched sequence patterns due to convergent evolution in non-homologous proteins has proven to be a successful strategy for computational SLiM prediction. Tools of the SLiMSuite package use this strategy, using a statistical model to identify SLiM enrichment based on the evolutionary relationships, amino acid composition and predicted disorder of the input proteins. The quality of input data is critical for successful SLiM prediction. Cytoscape provides a user-friendly, interactive environment to explore interaction networks and select proteins based on common features, such as shared interaction partners. SLiMScape embeds tools of the SLiMSuite package for de novo SLiM discovery (SLiMFinder and QSLiMFinder and identifying occurrences/enrichment of known SLiMs (SLiMProb within this interactive framework. SLiMScape makes it easier to (1 generate high quality hypothesis-driven datasets for these tools, and (2 visualise predicted SLiM occurrences within the context of the network. To generate new predictions, users can select nodes from a protein network or provide a set of Uniprot identifiers. SLiMProb also requires additional query motif input. Jobs are then run remotely on the SLiMSuite server (http://rest.slimsuite.unsw.edu.au for subsequent retrieval and visualisation. SLiMScape can also be used to retrieve and visualise results from jobs run directly on the server. SLiMScape and SLiMSuite are open source and freely available via GitHub under GNU licenses.
Non linear viscoelastic models
Agerkvist, Finn T.
2011-01-01
Viscoelastic eects are often present in loudspeaker suspensions, this can be seen in the displacement transfer function which often shows a frequency dependent value below the resonance frequency. In this paper nonlinear versions of the standard linear solid model (SLS) are investigated....... The simulations show that the nonlinear version of the Maxwell SLS model can result in a time dependent small signal stiness while the Kelvin Voight version does not....
Radar and electronic navigation
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
Survey of computer vision technology for UVA navigation
Xie, Bo; Fan, Xiang; Li, Sijian
2017-11-01
Navigation based on computer version technology, which has the characteristics of strong independence, high precision and is not susceptible to electrical interference, has attracted more and more attention in the filed of UAV navigation research. Early navigation project based on computer version technology mainly applied to autonomous ground robot. In recent years, the visual navigation system is widely applied to unmanned machine, deep space detector and underwater robot. That further stimulate the research of integrated navigation algorithm based on computer version technology. In China, with many types of UAV development and two lunar exploration, the three phase of the project started, there has been significant progress in the study of visual navigation. The paper expounds the development of navigation based on computer version technology in the filed of UAV navigation research and draw a conclusion that visual navigation is mainly applied to three aspects as follows.(1) Acquisition of UAV navigation parameters. The parameters, including UAV attitude, position and velocity information could be got according to the relationship between the images from sensors and carrier's attitude, the relationship between instant matching images and the reference images and the relationship between carrier's velocity and characteristics of sequential images.(2) Autonomous obstacle avoidance. There are many ways to achieve obstacle avoidance in UAV navigation. The methods based on computer version technology ,including feature matching, template matching, image frames and so on, are mainly introduced. (3) The target tracking, positioning. Using the obtained images, UAV position is calculated by using optical flow method, MeanShift algorithm, CamShift algorithm, Kalman filtering and particle filter algotithm. The paper expounds three kinds of mainstream visual system. (1) High speed visual system. It uses parallel structure, with which image detection and processing are
Indoor wayfinding and navigation
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.
Opshaug, Guttorm Ringstad
There are times and places where conventional navigation systems, such as the Global Positioning System (GPS), are unavailable due to anything from temporary signal occultations to lack of navigation system infrastructure altogether. The goal of the Leapfrog Navigation System (LNS) is to provide localized positioning services for such cases. The concept behind leapfrog navigation is to advance a group of navigation units teamwise into an area of interest. In a practical 2-D case, leapfrogging assumes known initial positions of at least two currently stationary navigation units. Two or more mobile units can then start to advance into the area of interest. The positions of the mobiles are constantly being calculated based on cross-range distance measurements to the stationary units, as well as cross-ranges among the mobiles themselves. At some point the mobile units stop, and the stationary units are released to move. This second team of units (now mobile) can then overtake the first team (now stationary) and travel even further towards the common goal of the group. Since there always is one stationary team, the position of any unit can be referenced back to the initial positions. Thus, LNS provides absolute positioning. I developed navigation algorithms needed to solve leapfrog positions based on cross-range measurements. I used statistical tools to predict how position errors would grow as a function of navigation unit geometry, cross-range measurement accuracy and previous position errors. Using this knowledge I predicted that a 4-unit Leapfrog Navigation System using 100 m baselines and 200 m leap distances could travel almost 15 km before accumulating absolute position errors of 10 m (1sigma). Finally, I built a prototype leapfrog navigation system using 4 GPS transceiver ranging units. I placed the 4 units in the vertices a 10m x 10m square, and leapfrogged the group 20 meters forwards, and then back again (40 m total travel). Average horizontal RMS position
Tanwiwat Jaikuna
2017-02-01
Full Text Available Purpose: To develop an in-house software program that is able to calculate and generate the biological dose distribution and biological dose volume histogram by physical dose conversion using the linear-quadratic-linear (LQL model. Material and methods : The Isobio software was developed using MATLAB version 2014b to calculate and generate the biological dose distribution and biological dose volume histograms. The physical dose from each voxel in treatment planning was extracted through Computational Environment for Radiotherapy Research (CERR, and the accuracy was verified by the differentiation between the dose volume histogram from CERR and the treatment planning system. An equivalent dose in 2 Gy fraction (EQD2 was calculated using biological effective dose (BED based on the LQL model. The software calculation and the manual calculation were compared for EQD2 verification with pair t-test statistical analysis using IBM SPSS Statistics version 22 (64-bit. Results: Two and three-dimensional biological dose distribution and biological dose volume histogram were displayed correctly by the Isobio software. Different physical doses were found between CERR and treatment planning system (TPS in Oncentra, with 3.33% in high-risk clinical target volume (HR-CTV determined by D90%, 0.56% in the bladder, 1.74% in the rectum when determined by D2cc, and less than 1% in Pinnacle. The difference in the EQD2 between the software calculation and the manual calculation was not significantly different with 0.00% at p-values 0.820, 0.095, and 0.593 for external beam radiation therapy (EBRT and 0.240, 0.320, and 0.849 for brachytherapy (BT in HR-CTV, bladder, and rectum, respectively. Conclusions : The Isobio software is a feasible tool to generate the biological dose distribution and biological dose volume histogram for treatment plan evaluation in both EBRT and BT.
Restricted Navigation Areas - USACE IENC
Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...
Educational and Scientific Applications of the \\itTime Navigator}
Cole, M.; Snow, J. T.; Slatt, R. M.
2001-05-01
Several recent conferences have noted the need to focus on the evolving interface between research and education at all levels of science, mathematics, engineering, and technology education. This interface, which is a distinguishing feature of graduate education in the U.S., is increasingly in demand at the undergraduate and K-12 levels, particularly in the earth sciences. In this talk, we present a new database for earth systems science and will explore applications to K-12 and undergraduate education, as well as the scientific and graduate role. The University of Oklahoma, College of Geosciences is in the process of acquiring the \\itTime Navigator}, a multi-disciplinary, multimedia database, which will form the core asset of the Center for Earth Systems Science. The Center, whose mission is to further the understanding of the dynamic Earth within both the academic and the general public communities, will serve as a portal for research, information, and education for scientists and educators. \\itTime Navigator} was developed over a period of some twenty years by the noted British geoscience author, Ron Redfern, in connection with the recently published, \\itOrigins, the evolution of continents, oceans and life}, the third in a series of books for the educated layperson. Over the years \\itTime Navigator} has evolved into an interactive, multimedia database displaying much of the significant geological, paleontological, climatological, and tectonic events from the latest Proterozoic (750 MYA) through to the present. The focus is mainly on the Western Hemisphere and events associated with the coalescence and breakup of Pangea and the evolution of the earth into its present form. \\itOrigins} will be available as early as Fall 2001 as an interactive electronic book for the general, scientifically-literate public. While electronic books are unlikely to replace traditional print books, the format does allow non-linear exploration of content. We believe that the
Getting Lost Through Navigation
Debus, Michael S.
2017-01-01
In this presentation, I argued two things. First, that it is navigation that lies at the core of contemporary (3D-) videogames and that its analysis is of utmost importance. Second, that this analysis needs a more rigorous differentiation between specific acts of navigation. Considering the Oxford...... in videogames is a configurational rather than an interpretational one (Eskelinen 2001). Especially in the case of game spaces, navigation appears to be of importance (Wolf 2009; Flynn 2008). Further, it does not only play a crucial role for the games themselves, but also for the experience of the player...
Inertial navigation without accelerometers
Boehm, M.
The Kennedy-Thorndike (1932) experiment points to the feasibility of fiber-optic inertial velocimeters, to which state-of-the-art technology could furnish substantial sensitivity and accuracy improvements. Velocimeters of this type would obviate the use of both gyros and accelerometers, and allow inertial navigation to be conducted together with vehicle attitude control, through the derivation of rotation rates from the ratios of the three possible velocimeter pairs. An inertial navigator and reference system based on this approach would probably have both fewer components and simpler algorithms, due to the obviation of the first level of integration in classic inertial navigators.
Semiotic resources for navigation
Due, Brian Lystgaard; Lange, Simon Bierring
2018-01-01
This paper describes two typical semiotic resources blind people use when navigating in urban areas. Everyone makes use of a variety of interpretive semiotic resources and senses when navigating. For sighted individuals, this especially involves sight. Blind people, however, must rely on everything...... else than sight, thereby substituting sight with other modalities and distributing the navigational work to other semiotic resources. Based on a large corpus of fieldwork among blind people in Denmark, undertaking observations, interviews, and video recordings of their naturally occurring practices...... of walking and navigating, this paper shows how two prototypical types of semiotic resources function as helpful cognitive extensions: the guide dog and the white cane. This paper takes its theoretical and methodological perspective from EMCA multimodal interaction analysis....
USACE Navigation Channels 2012
California Natural Resource Agency — This dataset represents both San Francisco and Los Angeles District navigation channel lines. All San Francisco District channel lines were digitized from CAD files...
Banks, Martin
1999-01-01
.... Similarly, the problem of visual navigation is the recovery of an observer's self-motion with respect to the environment from the moving pattern of light reaching the eyes and the complex of extra...
... Cure About Us Initiatives News & Events Professional Resources Tinnitus Patient Navigator Want to get started on the ... unique and may require a different treatment workflow. Tinnitus Health-Care Providers If you, or someone you ...
Granato, Gregory E.
2006-01-01
The Kendall-Theil Robust Line software (KTRLine-version 1.0) is a Visual Basic program that may be used with the Microsoft Windows operating system to calculate parameters for robust, nonparametric estimates of linear-regression coefficients between two continuous variables. The KTRLine software was developed by the U.S. Geological Survey, in cooperation with the Federal Highway Administration, for use in stochastic data modeling with local, regional, and national hydrologic data sets to develop planning-level estimates of potential effects of highway runoff on the quality of receiving waters. The Kendall-Theil robust line was selected because this robust nonparametric method is resistant to the effects of outliers and nonnormality in residuals that commonly characterize hydrologic data sets. The slope of the line is calculated as the median of all possible pairwise slopes between points. The intercept is calculated so that the line will run through the median of input data. A single-line model or a multisegment model may be specified. The program was developed to provide regression equations with an error component for stochastic data generation because nonparametric multisegment regression tools are not available with the software that is commonly used to develop regression models. The Kendall-Theil robust line is a median line and, therefore, may underestimate total mass, volume, or loads unless the error component or a bias correction factor is incorporated into the estimate. Regression statistics such as the median error, the median absolute deviation, the prediction error sum of squares, the root mean square error, the confidence interval for the slope, and the bias correction factor for median estimates are calculated by use of nonparametric methods. These statistics, however, may be used to formulate estimates of mass, volume, or total loads. The program is used to read a two- or three-column tab-delimited input file with variable names in the first row and
Navigating the Zika panic [version 1; referees: 2 approved
Nathan D. Grubaugh
2016-08-01
Full Text Available The epidemics of Ebola virus in West Africa and Zika virus in America highlight how viruses can explosively emerge into new territories. These epidemics also exposed how unprepared we are to handle infectious disease emergencies. This is also true when we consider hypothesized new clinical features of infection, such as the associations between Zika virus infection and severe neurological disease, including microcephaly and Guillain-Barré syndrome. On the surface, these pathologies appear to be new features of Zika virus infection, however, causal relationships have not yet been established. Decades of limited Zika virus research are making us scramble to determine the true drivers behind the epidemic, often at the expense of over-speculation without credible evidence. Here we review the literature and find no conclusive evidence at this time for significant biological differences between the American Zika virus strains and those circulating elsewhere. Rather, the epidemic scale in the Americas may be facilitated by an abnormally warm climate, dense human and mosquito populations, and previous exposure to other viruses. Severe disease associated with Zika virus may therefore not be a new trait for the virus, rather it may have been overlooked due to previously small outbreaks. Much of the recent panic regarding Zika virus has been about the Olympics in Brazil. We do not find any substantial evidence that the Olympics will result in a significant number of new Zika virus infections (~10 predicted or that the Olympics will promote further epidemic spread over what is already expected. The Zika virus epidemic in the Americas is a serious situation and decisions based on solid scientific evidence - not hyped media speculations - are required for effective outbreak response.
Krivonos, S.O.; Sorin, A.S.
1994-06-01
We show that the Zamolodchikov's and Polyakov-Bershadsky nonlinear algebras W 3 and W (2) 3 can be embedded as subalgebras into some linear algebras with finite set of currents. Using these linear algebras we find new field realizations of W (2) 3 and W 3 which could be a starting point for constructing new versions of W-string theories. We also reveal a number of hidden relationships between W 3 and W (2) 3 . We conjecture that similar linear algebras can exist for other W-algebra as well. (author). 10 refs
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...
Navigating in higher education
Thingholm, Hanne Balsby; Reimer, David; Keiding, Tina Bering
Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur, Informati......Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur...
Gee, Stephanie; Skovdal, Morten
2017-01-01
This paper draws on interview data to examine how international health care workers navigated risk during the unprecedented Ebola outbreak in West Africa. It identifies the importance of place in risk perception, including how different spatial localities give rise to different feelings of threat...... or safety, some from the construction of physical boundaries, and others mediated through aspects of social relations, such as trust, communication and team dynamics. Referring to these spatial localities as ‘riskscapes’, the paper calls for greater recognition of the role of place in understanding risk...... perception, and how people navigate risk....
Axler, Sheldon
2015-01-01
This best-selling textbook for a second course in linear algebra is aimed at undergrad math majors and graduate students. The novel approach taken here banishes determinants to the end of the book. The text focuses on the central goal of linear algebra: understanding the structure of linear operators on finite-dimensional vector spaces. The author has taken unusual care to motivate concepts and to simplify proofs. A variety of interesting exercises in each chapter helps students understand and manipulate the objects of linear algebra. The third edition contains major improvements and revisions throughout the book. More than 300 new exercises have been added since the previous edition. Many new examples have been added to illustrate the key ideas of linear algebra. New topics covered in the book include product spaces, quotient spaces, and dual spaces. Beautiful new formatting creates pages with an unusually pleasant appearance in both print and electronic versions. No prerequisites are assumed other than the ...
Navigating on handheld displays: Dynamic versus Static Keyhole Navigation
Mehra, S.; Werkhoven, P.; Worring, M.
2006-01-01
Handheld displays leave little space for the visualization and navigation of spatial layouts representing rich information spaces. The most common navigation method for handheld displays is static peephole navigation: The peephole is static and we move the spatial layout behind it (scrolling). A
Improving Canada's Marine Navigation System through e-Navigation
Daniel Breton
2016-06-01
The conclusion proposed is that on-going work with key partners and stakeholders can be used as the primary mechanism to identify e-Navigation related innovation and needs, and to prioritize next steps. Moving forward in Canada, implementation of new e-navigation services will continue to be stakeholder driven, and used to drive improvements to Canada's marine navigation system.
Nautical Navigation Aids (NAVAID) Locations
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,...
Inland Electronic Navigational Charts (IENC)
Army Corps of Engineers, Department of the Army, Department of Defense — These Inland Electronic Navigational Charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...
Hansen, Carsten Ørts; Grønsedt, Peter; Hendriksen, Christian
This report examines the effect that ECA-zone regulation has on the optimal vessel fuel strategies for compliance. The findings of this report are trifold, and this report is coupled with a calculation tool which is released to assist ship-owners in the ECA decision making. The first key insight...... much time their operated vessels navigate the ECA in the future....
Crasmareanu Mircea
2017-12-01
Full Text Available We consider the paracomplex version of the notion of mixed linear spaces introduced by M. Jurchescu in [4] by replacing the complex unit i with the paracomplex unit j, j2 = 1. The linear algebra of these spaces is studied with a special view towards their morphisms.
Shilov, Georgi E
1977-01-01
Covers determinants, linear spaces, systems of linear equations, linear functions of a vector argument, coordinate transformations, the canonical form of the matrix of a linear operator, bilinear and quadratic forms, Euclidean spaces, unitary spaces, quadratic forms in Euclidean and unitary spaces, finite-dimensional space. Problems with hints and answers.
Linear versus non-linear supersymmetry, in general
Ferrara, Sergio [Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); INFN - Laboratori Nazionali di Frascati,Via Enrico Fermi 40, I-00044 Frascati (Italy); Department of Physics and Astronomy, UniversityC.L.A.,Los Angeles, CA 90095-1547 (United States); Kallosh, Renata [SITP and Department of Physics, Stanford University,Stanford, California 94305 (United States); Proeyen, Antoine Van [Institute for Theoretical Physics, Katholieke Universiteit Leuven,Celestijnenlaan 200D, B-3001 Leuven (Belgium); Wrase, Timm [Institute for Theoretical Physics, Technische Universität Wien,Wiedner Hauptstr. 8-10, A-1040 Vienna (Austria)
2016-04-12
We study superconformal and supergravity models with constrained superfields. The underlying version of such models with all unconstrained superfields and linearly realized supersymmetry is presented here, in addition to the physical multiplets there are Lagrange multiplier (LM) superfields. Once the equations of motion for the LM superfields are solved, some of the physical superfields become constrained. The linear supersymmetry of the original models becomes non-linearly realized, its exact form can be deduced from the original linear supersymmetry. Known examples of constrained superfields are shown to require the following LM’s: chiral superfields, linear superfields, general complex superfields, some of them are multiplets with a spin.
Linear versus non-linear supersymmetry, in general
Ferrara, Sergio; Kallosh, Renata; Proeyen, Antoine Van; Wrase, Timm
2016-01-01
We study superconformal and supergravity models with constrained superfields. The underlying version of such models with all unconstrained superfields and linearly realized supersymmetry is presented here, in addition to the physical multiplets there are Lagrange multiplier (LM) superfields. Once the equations of motion for the LM superfields are solved, some of the physical superfields become constrained. The linear supersymmetry of the original models becomes non-linearly realized, its exact form can be deduced from the original linear supersymmetry. Known examples of constrained superfields are shown to require the following LM’s: chiral superfields, linear superfields, general complex superfields, some of them are multiplets with a spin.
Control algorithms for autonomous robot navigation
Jorgensen, C.C.
1985-01-01
This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced
Andersen, Jens Christian
2007-01-01
the current position to a desired destination. This thesis presents and experimentally validates solutions for road classification, obstacle avoidance and mission execution. The road classification is based on laser scanner measurements and supported at longer ranges by vision. The road classification...... is sufficiently sensitive to separate the road from flat roadsides, and to distinguish asphalt roads from gravelled roads. The vision-based road detection uses a combination of chromaticity and edge detection to outline the traversable part of the road based on a laser scanner classified sample area....... The perception of these two sensors are utilised by a path planner to allow a number of drive modes, and especially the ability to follow road edges are investigated. The navigation mission is controlled by a script language. The navigation script controls route sequencing, junction detection, junction crossing...
Relativistic Linear Restoring Force
Clark, D.; Franklin, J.; Mann, N.
2012-01-01
We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…
33 CFR 2.36 - Navigable waters of the United States, navigable waters, and territorial waters.
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navigable waters of the United States, navigable waters, and territorial waters. 2.36 Section 2.36 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL JURISDICTION Jurisdictional Terms § 2.36 Navigable waters...
Indoor navigation by image recognition
Choi, Io Teng; Leong, Chi Chong; Hong, Ka Wo; Pun, Chi-Man
2017-07-01
With the progress of smartphones hardware, it is simple on smartphone using image recognition technique such as face detection. In addition, indoor navigation system development is much slower than outdoor navigation system. Hence, this research proves a usage of image recognition technique for navigation in indoor environment. In this paper, we introduced an indoor navigation application that uses the indoor environment features to locate user's location and a route calculating algorithm to generate an appropriate path for user. The application is implemented on Android smartphone rather than iPhone. Yet, the application design can also be applied on iOS because the design is implemented without using special features only for Android. We found that digital navigation system provides better and clearer location information than paper map. Also, the indoor environment is ideal for Image recognition processing. Hence, the results motivate us to design an indoor navigation system using image recognition.
LINEAR2007, Linear-Linear Interpolation of ENDF Format Cross-Sections
2007-01-01
1 - Description of program or function: LINEAR converts evaluated cross sections in the ENDF/B format into a tabular form that is subject to linear-linear interpolation in energy and cross section. The code also thins tables of cross sections already in that form. Codes used subsequently need thus to consider only linear-linear data. IAEA1311/15: This version include the updates up to January 30, 2007. Changes in ENDF/B-VII Format and procedures, as well as the evaluations themselves, make it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2007 (2007 Version) to accurately process current ENDF/B-VII evaluations. The present code can handle all existing ENDF/B-VI evaluations through release 8, which will be the last release of ENDF/B-VI. Modifications from previous versions: - Linear VERS. 2007-1 (JAN. 2007): checked against all ENDF/B-VII; increased page size from 60,000 to 600,000 points 2 - Method of solution: Each section of data is considered separately. Each section of File 3, 23, and 27 data consists of a table of cross section versus energy with any of five interpolation laws. LINEAR will replace each section with a new table of energy versus cross section data in which the interpolation law is always linear in energy and cross section. The histogram (constant cross section between two energies) interpolation law is converted to linear-linear by substituting two points for each initial point. The linear-linear is not altered. For the log-linear, linear-log and log- log laws, the cross section data are converted to linear by an interval halving algorithm. Each interval is divided in half until the value at the middle of the interval can be approximated by linear-linear interpolation to within a given accuracy. The LINEAR program uses a multipoint fractional error thinning algorithm to minimize the size of each cross section table
China Satellite Navigation Conference
Liu, Jingnan; Fan, Shiwei; Wang, Feixue
2016-01-01
These Proceedings present selected research papers from CSNC2016, held during 18th-20th May in Changsha, China. The theme of CSNC2016 is Smart Sensing, Smart Perception. These papers discuss the technologies and applications of the Global Navigation Satellite System (GNSS), and the latest progress made in the China BeiDou System (BDS) especially. They are divided into 12 topics to match the corresponding sessions in CSNC2016, which broadly covered key topics in GNSS. Readers can learn about the BDS and keep abreast of the latest advances in GNSS techniques and applications.
China Satellite Navigation Conference
Liu, Jingnan; Yang, Yuanxi; Fan, Shiwei; Yu, Wenxian
2017-01-01
These proceedings present selected research papers from CSNC2017, held during 23th-25th May in Shanghai, China. The theme of CSNC2017 is Positioning, Connecting All. These papers discuss the technologies and applications of the Global Navigation Satellite System (GNSS), and the latest progress made in the China BeiDou System (BDS) especially. They are divided into 12 topics to match the corresponding sessions in CSNC2017, which broadly covered key topics in GNSS. Readers can learn about the BDS and keep abreast of the latest advances in GNSS techniques and applications.
Understanding satellite navigation
Acharya, Rajat
2014-01-01
This book explains the basic principles of satellite navigation technology with the bare minimum of mathematics and without complex equations. It helps you to conceptualize the underlying theory from first principles, building up your knowledge gradually using practical demonstrations and worked examples. A full range of MATLAB simulations is used to visualize concepts and solve problems, allowing you to see what happens to signals and systems with different configurations. Implementation and applications are discussed, along with some special topics such as Kalman Filter and Ionosphere. W
Parametric Covariance Model for Horizon-Based Optical Navigation
Hikes, Jacob; Liounis, Andrew J.; Christian, John A.
2016-01-01
This Note presents an entirely parametric version of the covariance for horizon-based optical navigation measurements. The covariance can be written as a function of only the spacecraft position, two sensor design parameters, the illumination direction, the size of the observed planet, the size of the lit arc to be used, and the total number of observed horizon points. As a result, one may now more clearly understand the sensitivity of horizon-based optical navigation performance as a function of these key design parameters, which is insight that was obscured in previous (and nonparametric) versions of the covariance. Finally, the new parametric covariance is shown to agree with both the nonparametric analytic covariance and results from a Monte Carlo analysis.
Multitarget Approaches to Robust Navigation
National Aeronautics and Space Administration — The performance, stability, and statistical consistency of a vehicle's navigation algorithm are vitally important to the success and safety of its mission....
Advancements in Optical Navigation Capabilities
National Aeronautics and Space Administration — The Goddard Image Analysis and Navigation Tool (GIANT) is a tool that was developed for the Origins, Spectral Interpretation, Resource Identification,...
Learning for Autonomous Navigation
Angelova, Anelia; Howard, Andrew; Matthies, Larry; Tang, Benyang; Turmon, Michael; Mjolsness, Eric
2005-01-01
Robotic ground vehicles for outdoor applications have achieved some remarkable successes, notably in autonomous highway following (Dickmanns, 1987), planetary exploration (1), and off-road navigation on Earth (1). Nevertheless, major challenges remain to enable reliable, high-speed, autonomous navigation in a wide variety of complex, off-road terrain. 3-D perception of terrain geometry with imaging range sensors is the mainstay of off-road driving systems. However, the stopping distance at high speed exceeds the effective lookahead distance of existing range sensors. Prospects for extending the range of 3-D sensors is strongly limited by sensor physics, eye safety of lasers, and related issues. Range sensor limitations also allow vehicles to enter large cul-de-sacs even at low speed, leading to long detours. Moreover, sensing only terrain geometry fails to reveal mechanical properties of terrain that are critical to assessing its traversability, such as potential for slippage, sinkage, and the degree of compliance of potential obstacles. Rovers in the Mars Exploration Rover (MER) mission have got stuck in sand dunes and experienced significant downhill slippage in the vicinity of large rock hazards. Earth-based off-road robots today have very limited ability to discriminate traversable vegetation from non-traversable vegetation or rough ground. It is impossible today to preprogram a system with knowledge of these properties for all types of terrain and weather conditions that might be encountered.
An Improved Version of the Fluxgate Compass Module
V. Petrucha
2007-01-01
Full Text Available Satellite based navigation systems (GPS are widely used for ground, air and marine navigation. In the case of a malfunction or satellite signal inaccessibility, some back-up navigation system is needed. An electronic compass can provide this function. The compass module described in this paper is designed for precise navigation purposes. The compass module is equipped with electronic tilt error compensation, and includes everything in one package – electronics with digital output, sensors. A typical application of this compass is in underground drilling. A critical parameter in this application is heading accuracy. A reading error of 1 degree can cause a displacement of 1.8 metres in the target area (length of tunnel 100 m. This is not acceptable in an urban conglomeration, and therefore a more accurate heading sensing device must be used. An improved version of this electronic compass is being finished.
Suwono.
1978-01-01
A linear gate providing a variable gate duration from 0,40μsec to 4μsec was developed. The electronic circuity consists of a linear circuit and an enable circuit. The input signal can be either unipolar or bipolar. If the input signal is bipolar, the negative portion will be filtered. The operation of the linear gate is controlled by the application of a positive enable pulse. (author)
Vretenar, M
2014-01-01
The main features of radio-frequency linear accelerators are introduced, reviewing the different types of accelerating structures and presenting the main characteristics aspects of linac beam dynamics
Linearization Method and Linear Complexity
Tanaka, Hidema
We focus on the relationship between the linearization method and linear complexity and show that the linearization method is another effective technique for calculating linear complexity. We analyze its effectiveness by comparing with the logic circuit method. We compare the relevant conditions and necessary computational cost with those of the Berlekamp-Massey algorithm and the Games-Chan algorithm. The significant property of a linearization method is that it needs no output sequence from a pseudo-random number generator (PRNG) because it calculates linear complexity using the algebraic expression of its algorithm. When a PRNG has n [bit] stages (registers or internal states), the necessary computational cost is smaller than O(2n). On the other hand, the Berlekamp-Massey algorithm needs O(N2) where N(≅2n) denotes period. Since existing methods calculate using the output sequence, an initial value of PRNG influences a resultant value of linear complexity. Therefore, a linear complexity is generally given as an estimate value. On the other hand, a linearization method calculates from an algorithm of PRNG, it can determine the lower bound of linear complexity.
Said-Houari, Belkacem
2017-01-01
This self-contained, clearly written textbook on linear algebra is easily accessible for students. It begins with the simple linear equation and generalizes several notions from this equation for the system of linear equations and introduces the main ideas using matrices. It then offers a detailed chapter on determinants and introduces the main ideas with detailed proofs. The third chapter introduces the Euclidean spaces using very simple geometric ideas and discusses various major inequalities and identities. These ideas offer a solid basis for understanding general Hilbert spaces in functional analysis. The following two chapters address general vector spaces, including some rigorous proofs to all the main results, and linear transformation: areas that are ignored or are poorly explained in many textbooks. Chapter 6 introduces the idea of matrices using linear transformation, which is easier to understand than the usual theory of matrices approach. The final two chapters are more advanced, introducing t...
Dynamic Transportation Navigation
Meng, Xiaofeng; Chen, Jidong
Miniaturization of computing devices, and advances in wireless communication and sensor technology are some of the forces that are propagating computing from the stationary desktop to the mobile outdoors. Some important classes of new applications that will be enabled by this revolutionary development include intelligent traffic management, location-based services, tourist services, mobile electronic commerce, and digital battlefield. Some existing application classes that will benefit from the development include transportation and air traffic control, weather forecasting, emergency response, mobile resource management, and mobile workforce. Location management, i.e., the management of transient location information, is an enabling technology for all these applications. In this chapter, we present the applications of moving objects management and their functionalities, in particular, the application of dynamic traffic navigation, which is a challenge due to the highly variable traffic state and the requirement of fast, on-line computations.
Gould, J L
1998-10-08
Navigating animals need to know both the bearing of their goal (the 'map' step), and how to determine that direction (the 'compass' step). Compasses are typically arranged in hierarchies, with magnetic backup as a last resort when celestial information is unavailable. Magnetic information is often essential to calibrating celestial cues, though, and repeated recalibration between celestial and magnetic compasses is important in many species. Most magnetic compasses are based on magnetite crystals, but others make use of induction or paramagnetic interactions between short-wavelength light and visual pigments. Though odors may be used in some cases, most if not all long-range maps probably depend on magnetite. Magnetitebased map senses are used to measure only latitude in some species, but provide the distance and direction of the goal in others.
Comprehension of Navigation Directions
Schneider, Vivian I.; Healy, Alice F.
2000-01-01
In an experiment simulating communication between air traffic controllers and pilots, subjects were given navigation instructions varying in length telling them to move in a space represented by grids on a computer screen. The subjects followed the instructions by clicking on the grids in the locations specified. Half of the subjects read the instructions, and half heard them. Half of the subjects in each modality condition repeated back the instructions before following them,and half did not. Performance was worse for the visual than for the auditory modality on the longer messages. Repetition of the instructions generally depressed performance, especially with the longer messages, which required more output than did the shorter messages, and especially with the visual modality, in which phonological recoding from the visual input to the spoken output was necessary. These results are explained in terms of the degrading effects of output interference on memory for instructions.
Navigation System of Marks Areas - USACE IENC
Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...
Stoll, R R
1968-01-01
Linear Algebra is intended to be used as a text for a one-semester course in linear algebra at the undergraduate level. The treatment of the subject will be both useful to students of mathematics and those interested primarily in applications of the theory. The major prerequisite for mastering the material is the readiness of the student to reason abstractly. Specifically, this calls for an understanding of the fact that axioms are assumptions and that theorems are logical consequences of one or more axioms. Familiarity with calculus and linear differential equations is required for understand
Solow, Daniel
2014-01-01
This text covers the basic theory and computation for a first course in linear programming, including substantial material on mathematical proof techniques and sophisticated computation methods. Includes Appendix on using Excel. 1984 edition.
Liesen, Jörg
2015-01-01
This self-contained textbook takes a matrix-oriented approach to linear algebra and presents a complete theory, including all details and proofs, culminating in the Jordan canonical form and its proof. Throughout the development, the applicability of the results is highlighted. Additionally, the book presents special topics from applied linear algebra including matrix functions, the singular value decomposition, the Kronecker product and linear matrix equations. The matrix-oriented approach to linear algebra leads to a better intuition and a deeper understanding of the abstract concepts, and therefore simplifies their use in real world applications. Some of these applications are presented in detailed examples. In several ‘MATLAB-Minutes’ students can comprehend the concepts and results using computational experiments. Necessary basics for the use of MATLAB are presented in a short introduction. Students can also actively work with the material and practice their mathematical skills in more than 300 exerc...
Berberian, Sterling K
2014-01-01
Introductory treatment covers basic theory of vector spaces and linear maps - dimension, determinants, eigenvalues, and eigenvectors - plus more advanced topics such as the study of canonical forms for matrices. 1992 edition.
Searle, Shayle R
2012-01-01
This 1971 classic on linear models is once again available--as a Wiley Classics Library Edition. It features material that can be understood by any statistician who understands matrix algebra and basic statistical methods.
De Vreese, L P; Gomiero, T; Uberti, M; De Bastiani, E; Weger, E; Mantesso, U; Marangoni, A
2015-04-01
(a) A psychometric validation of an Italian version of the Alzheimer's Functional Assessment Tool scale (AFAST-I), designed for informant-based assessment of the degree of impairment and of assistance required in seven basic daily activities in adult/elderly people with intellectual disabilities (ID) and (suspected) dementia; (b) a pilot analysis of its clinical significance with traditional statistical procedures and with an artificial neural network. AFAST-I was administered to the professional caregivers of 61 adults/seniors with ID with a mean age (± SD) of 53.4 (± 7.7) years (36% with Down syndrome). Internal consistency (Cronbach's α coefficient), inter/intra-rater reliabilities (intra-class coefficients, ICC) and concurrent, convergent and discriminant validity (Pearson's r coefficients) were computed. Clinical significance was probed by analysing the relationships among AFAST-I scores and the Sum of Cognitive Scores (SCS) and the Sum of Social Scores (SOS) of the Dementia Questionnaire for Persons with Intellectual Disabilities (DMR-I) after standardisation of their raw scores in equivalent scores (ES). An adaptive artificial system (AutoContractive Maps, AutoCM) was applied to all the variables recorded in the study sample, aimed at uncovering which variable occupies a central position and supports the entire network made up of the remaining variables interconnected among themselves with different weights. AFAST-I shows a high level of internal homogeneity with a Cronbach's α coefficient of 0.92. Inter-rater and intra-rater reliabilities were also excellent with ICC correlations of 0.96 and 0.93, respectively. The results of the analyses of the different AFAST-I validities all go in the expected direction: concurrent validity (r=-0.87 with ADL); convergent validity (r=0.63 with SCS; r=0.61 with SOS); discriminant validity (r=0.21 with the frequency of occurrence of dementia-related Behavioral Excesses of the Assessment for Adults with Developmental
Lunar Navigation Architecture Design Considerations
D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael
2009-01-01
The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).
Christofilos, N.C.; Polk, I.J.
1959-02-17
Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.
Disturbance Decoupling of Switched Linear Systems
Yurtseven, E.; Heemels, W.P.M.H.; Camlibel, M.K.
2010-01-01
In this paper we consider disturbance decoupling problems for switched linear systems. We will provide necessary and sufficient conditions for three different versions of disturbance decoupling, which differ based on which signals are considered to be the disturbance. In the first version the
Monitoring Completed Navigation Projects Program
Bottin, Jr., Robert R
2001-01-01
... (MCNP) Program. The program was formerly known as the Monitoring Completed Coastal Projects Program, but was modified in the late 1990s to include all navigation projects, inland as well as coastal...
NOAA Electronic Navigational Charts (ENC)
National Oceanic and Atmospheric Administration, Department of Commerce — The Office of Coast Survey (OCS) has been involved in the development of a NOAA Electronic Navigational Chart (NOAA ENC) suite to support the marine transportation...
Olive, David J
2017-01-01
This text covers both multiple linear regression and some experimental design models. The text uses the response plot to visualize the model and to detect outliers, does not assume that the error distribution has a known parametric distribution, develops prediction intervals that work when the error distribution is unknown, suggests bootstrap hypothesis tests that may be useful for inference after variable selection, and develops prediction regions and large sample theory for the multivariate linear regression model that has m response variables. A relationship between multivariate prediction regions and confidence regions provides a simple way to bootstrap confidence regions. These confidence regions often provide a practical method for testing hypotheses. There is also a chapter on generalized linear models and generalized additive models. There are many R functions to produce response and residual plots, to simulate prediction intervals and hypothesis tests, to detect outliers, and to choose response trans...
Alcaraz, J.
2001-01-01
After several years of study e''+ e''- linear colliders in the TeV range have emerged as the major and optimal high-energy physics projects for the post-LHC era. These notes summarize the present status form the main accelerator and detector features to their physics potential. The LHC era. These notes summarize the present status, from the main accelerator and detector features to their physics potential. The LHC is expected to provide first discoveries in the new energy domain, whereas an e''+ e''- linear collider in the 500 GeV-1 TeV will be able to complement it to an unprecedented level of precision in any possible areas: Higgs, signals beyond the SM and electroweak measurements. It is evident that the Linear Collider program will constitute a major step in the understanding of the nature of the new physics beyond the Standard Model. (Author) 22 refs
Edwards, Harold M
1995-01-01
In his new undergraduate textbook, Harold M Edwards proposes a radically new and thoroughly algorithmic approach to linear algebra Originally inspired by the constructive philosophy of mathematics championed in the 19th century by Leopold Kronecker, the approach is well suited to students in the computer-dominated late 20th century Each proof is an algorithm described in English that can be translated into the computer language the class is using and put to work solving problems and generating new examples, making the study of linear algebra a truly interactive experience Designed for a one-semester course, this text adopts an algorithmic approach to linear algebra giving the student many examples to work through and copious exercises to test their skills and extend their knowledge of the subject Students at all levels will find much interactive instruction in this text while teachers will find stimulating examples and methods of approach to the subject
Navarro-Santana, B; Duarez-Coronado, M; Plaza-Arranz, J
2016-08-01
To analyze the rate of successful external cephalic versions in our center and caesarean sections that would be avoided with the use of external cephalic versions. From January 2012 to March 2016 external cephalic versions carried out at our center, which were a total of 52. We collected data about female age, gestational age at the time of the external cephalic version, maternal body mass index (BMI), fetal variety and situation, fetal weight, parity, location of the placenta, amniotic fluid index (ILA), tocolysis, analgesia, and newborn weight at birth, minor adverse effects (dizziness, hypotension and maternal pain) and major adverse effects (tachycardia, bradycardia, decelerations and emergency cesarean section). 45% of the versions were unsuccessful and 55% were successful. The percentage of successful vaginal delivery in versions was 84% (4% were instrumental) and 15% of caesarean sections. With respect to the variables studied, only significant differences in birth weight were found; suggesting that birth weight it is related to the outcome of external cephalic version. Probably we did not find significant differences due to the number of patients studied. For women with breech presentation, we recommend external cephalic version before the expectant management or performing a cesarean section. The external cephalic version increases the proportion of fetuses in cephalic presentation and also decreases the rate of caesarean sections.
An Imaging Sensor-Aided Vision Navigation Approach that Uses a Geo-Referenced Image Database.
Li, Yan; Hu, Qingwu; Wu, Meng; Gao, Yang
2016-01-28
In determining position and attitude, vision navigation via real-time image processing of data collected from imaging sensors is advanced without a high-performance global positioning system (GPS) and an inertial measurement unit (IMU). Vision navigation is widely used in indoor navigation, far space navigation, and multiple sensor-integrated mobile mapping. This paper proposes a novel vision navigation approach aided by imaging sensors and that uses a high-accuracy geo-referenced image database (GRID) for high-precision navigation of multiple sensor platforms in environments with poor GPS. First, the framework of GRID-aided vision navigation is developed with sequence images from land-based mobile mapping systems that integrate multiple sensors. Second, a highly efficient GRID storage management model is established based on the linear index of a road segment for fast image searches and retrieval. Third, a robust image matching algorithm is presented to search and match a real-time image with the GRID. Subsequently, the image matched with the real-time scene is considered to calculate the 3D navigation parameter of multiple sensor platforms. Experimental results show that the proposed approach retrieves images efficiently and has navigation accuracies of 1.2 m in a plane and 1.8 m in height under GPS loss in 5 min and within 1500 m.
Schipper, Harvey
2016-02-01
Carter is a bellwether decision, an adjudication on a narrow point of law whose implications are vast across society, and whose impact may not be realized for years. Coupled with Quebec's Act Respecting End-of-life Care it has sharply changed the legal landscape with respect to actively ending a person's life. "Medically assisted dying" will be permitted under circumstances, and through processes, which have yet to be operationally defined. This decision carries with it moral assumptions, which mean that it will be difficult to reach a unifying consensus. For some, the decision and Act reflect a modern acknowledgement of individual autonomy. For others, allowing such acts is morally unspeakable. Having opened the Pandora's Box, the question becomes one of navigating a tolerable societal path. I believe it is possible to achieve a workable solution based on the core principle that "medically assisted dying" should be a very rarely employed last option, subject to transparent ongoing review, specifically as to why it was deemed necessary. My analysis is based on 1. The societal conditions in which have fostered demand for "assisted dying", 2. Actions in other jurisdictions, 3. Carter and Quebec Bill 52, 4. Political considerations, 5. Current medical practice. Leading to a series of recommendations regarding. 1. Legislation and regulation, 2. The role of professional regulatory agencies, 3. Medical professions education and practice, 4. Public education, 5. Health care delivery and palliative care. Given the burden of public opinion, and the legal steps already taken, a process for assisted-dying is required. However, those legal and regulatory steps should only be considered a necessary and defensive first step in a two stage process. The larger goal, the second step, is to drive the improvement of care, and thus minimize assisted-dying.
Compact autonomous navigation system (CANS)
Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.
2017-11-01
Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].
Macduff, Matt C.; Lee, Benno; Beus, Sherman J.
2014-06-29
Using the history of ARM data files, we designed and demonstrated a data versioning paradigm that is feasible. Assigning versions to sets of files that are modified with some special assumptions and domain specific rules was effective in the case of ARM data, which has more than 5000 datastreams and 500TB of data.
Karloff, Howard
1991-01-01
To this reviewer’s knowledge, this is the first book accessible to the upper division undergraduate or beginning graduate student that surveys linear programming from the Simplex Method…via the Ellipsoid algorithm to Karmarkar’s algorithm. Moreover, its point of view is algorithmic and thus it provides both a history and a case history of work in complexity theory. The presentation is admirable; Karloff's style is informal (even humorous at times) without sacrificing anything necessary for understanding. Diagrams (including horizontal brackets that group terms) aid in providing clarity. The end-of-chapter notes are helpful...Recommended highly for acquisition, since it is not only a textbook, but can also be used for independent reading and study. —Choice Reviews The reader will be well served by reading the monograph from cover to cover. The author succeeds in providing a concise, readable, understandable introduction to modern linear programming. —Mathematics of Computing This is a textbook intend...
33 CFR 401.54 - Interference with navigation aids.
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...
SMILE a new version for the RADLAC II linear accelerator
Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Pankuch, P.J.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R.
1991-01-01
The authors present here the SMILE modification of the RADLAC II accelerator which enabled them to produce high quality 12-14 MV, 100 kA beams. The modification of replacing the 40-kA 4-MV beam injector, magnetic vacuum transport and accelerating gaps by a long cathode shank which adds up the voltages of the 8 pulse forming lines. The beam now is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with β perpendicular ≤ 0.1 and radius r b ≤ 2 cm are routinely obtained and extracted from a small magnetically immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions
GPS Navigation and Tracking Device
Yahya Salameh Khraisat
2011-10-01
Full Text Available Since the introduction of GPS Navigation systems in the marketplace, consumers and businesses have been coming up with innovative ways to use the technology in their everyday life. GPS Navigation and Tracking systems keep us from getting lost when we are in strange locations, they monitor children when they are away from home, keep track of business vehicles and can even let us know where a philandering partner is at all times. Because of this we attend to build a GPS tracking device to solve the mentioned problems. Our work consists of the GPS module that collects data from satellites and calculates the position information before transmitting them to the user’s PC (of Navigation system or observers (of Tracking System using wireless technology (GSM.
Springer, T A
1998-01-01
"[The first] ten chapters...are an efficient, accessible, and self-contained introduction to affine algebraic groups over an algebraically closed field. The author includes exercises and the book is certainly usable by graduate students as a text or for self-study...the author [has a] student-friendly style… [The following] seven chapters... would also be a good introduction to rationality issues for algebraic groups. A number of results from the literature…appear for the first time in a text." –Mathematical Reviews (Review of the Second Edition) "This book is a completely new version of the first edition. The aim of the old book was to present the theory of linear algebraic groups over an algebraically closed field. Reading that book, many people entered the research field of linear algebraic groups. The present book has a wider scope. Its aim is to treat the theory of linear algebraic groups over arbitrary fields. Again, the author keeps the treatment of prerequisites self-contained. The material of t...
Quantum linear Boltzmann equation
Vacchini, Bassano; Hornberger, Klaus
2009-01-01
We review the quantum version of the linear Boltzmann equation, which describes in a non-perturbative fashion, by means of scattering theory, how the quantum motion of a single test particle is affected by collisions with an ideal background gas. A heuristic derivation of this Lindblad master equation is presented, based on the requirement of translation-covariance and on the relation to the classical linear Boltzmann equation. After analyzing its general symmetry properties and the associated relaxation dynamics, we discuss a quantum Monte Carlo method for its numerical solution. We then review important limiting forms of the quantum linear Boltzmann equation, such as the case of quantum Brownian motion and pure collisional decoherence, as well as the application to matter wave optics. Finally, we point to the incorporation of quantum degeneracies and self-interactions in the gas by relating the equation to the dynamic structure factor of the ambient medium, and we provide an extension of the equation to include internal degrees of freedom.
33 CFR 66.05-100 - Designation of navigable waters as State waters for private aids to navigation.
2010-07-01
... as State waters for private aids to navigation. 66.05-100 Section 66.05-100 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-100 Designation of navigable waters as State waters for private aids to...
Estimation with applications to tracking and navigation theory, algorthims and software
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
Surface navigation on Mars with a Navigation Satellite
Vijayaraghavan, A.; Thurman, Sam W.; Kahn, Robert D.; Hastrup, Rolf C.
Radiometric navigation data from the Deep Space Network (DSN) stations on the earth to transponders and other surface elements such as rovers and landers on Mars, can determine their positions to only within a kilometer in inertial space. The positional error is mostly in the z-component of the surface element parallel to the Martian spin-axis. However, with Doppler and differenced-Doppler data from a Navigation Satellite in orbit around Mars to two or more of such transponders on the planetary surface, their positions can be determined to within 15 meters (or 20 meters for one-way Doppler beacons on Mars) in inertial space. In this case, the transponders (or other vehicles) on Mars need not even be capable of directly communicating to the earth. When the Navigation Satellite data is complemented by radiometric observations from the DSN stations also, directly to the surface elements on Mars, their positions can be determined to within 3 meters in inertial space. The relative positions of such surface elements on Mars (relative to one another) in Mars-fixed coordinates, however, can be determined to within 5 meters from simply range and Doppler data from the DSN stations to the surface elements. These results are obtained from covariance studies assuming X-band data noise levels and data-arcs not exceeding 10 days. They are significant in the planning and deployment of a Mars-based navigation network necessary to support real-time operations during critical phases of manned exploration of Mars.
Reduction of Linear Programming to Linear Approximation
Vaserstein, Leonid N.
2006-01-01
It is well known that every Chebyshev linear approximation problem can be reduced to a linear program. In this paper we show that conversely every linear program can be reduced to a Chebyshev linear approximation problem.
A kernel version of spatial factor analysis
Nielsen, Allan Aasbjerg
2009-01-01
. Schölkopf et al. introduce kernel PCA. Shawe-Taylor and Cristianini is an excellent reference for kernel methods in general. Bishop and Press et al. describe kernel methods among many other subjects. Nielsen and Canty use kernel PCA to detect change in univariate airborne digital camera images. The kernel...... version of PCA handles nonlinearities by implicitly transforming data into high (even infinite) dimensional feature space via the kernel function and then performing a linear analysis in that space. In this paper we shall apply kernel versions of PCA, maximum autocorrelation factor (MAF) analysis...
Tip, A.
1998-06-01
Starting from Maxwell's equations for a linear, nonconducting, absorptive, and dispersive medium, characterized by the constitutive equations D(x,t)=ɛ1(x)E(x,t)+∫t-∞dsχ(x,t-s)E(x,s) and H(x,t)=B(x,t), a unitary time evolution and canonical formalism is obtained. Given the complex, coordinate, and frequency-dependent, electric permeability ɛ(x,ω), no further assumptions are made. The procedure leads to a proper definition of band gaps in the periodic case and a new continuity equation for energy flow. An S-matrix formalism for scattering from lossy objects is presented in full detail. A quantized version of the formalism is derived and applied to the generation of Čerenkov and transition radiation as well as atomic decay. The last case suggests a useful generalization of the density of states to the absorptive situation.
Xiao, Mengli; Zhang, Yongbo; Fu, Huimin; Wang, Zhihua
2018-05-01
High-precision navigation algorithm is essential for the future Mars pinpoint landing mission. The unknown inputs caused by large uncertainties of atmospheric density and aerodynamic coefficients as well as unknown measurement biases may cause large estimation errors of conventional Kalman filters. This paper proposes a derivative-free version of nonlinear unbiased minimum variance filter for Mars entry navigation. This filter has been designed to solve this problem by estimating the state and unknown measurement biases simultaneously with derivative-free character, leading to a high-precision algorithm for the Mars entry navigation. IMU/radio beacons integrated navigation is introduced in the simulation, and the result shows that with or without radio blackout, our proposed filter could achieve an accurate state estimation, much better than the conventional unscented Kalman filter, showing the ability of high-precision Mars entry navigation algorithm. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.
Navigation in Cross-cultural business relationships
Andersen, Poul Houman
2001-01-01
Cross-cultural business navigation concerns the process of handling the complexity of several interacting cultural spheres of influence......Cross-cultural business navigation concerns the process of handling the complexity of several interacting cultural spheres of influence...
An Integrated Approach to Electronic Navigation
Shaw, Peter; Pettus, Bill
2001-01-01
While the Global Positioning System (GPS) is and will continue to be an excellent navigation system, it is neither flawless nor is it the only system employed in the navigation of today's seagoing warfighters...
Global Positioning System Navigation Algorithms
1977-05-01
Historical Remarks on Navigation In Greek mythology , Odysseus sailed safely by the Sirens only to encounter the monsters Scylla and Charybdis...TNED 000 00 1(.7 BIBLIOGRAPHY 1. Pinsent, John. Greek Mythology . Paul Hamlyn, London, 1969. 2. Kline, Morris. Mathematical Thought from Ancient to
Conceptual Grounds of Navigation Safety
Vladimir Torskiy
2016-04-01
Full Text Available The most important global problem being solved by the whole world community nowadays is to provide sustainable mankind development. Recent research in the field of sustainable development states that civilization safety is impossible without transfer sustainable development. At the same time, sustainable development (i.e. preservation of human culture and biosphere is impossible as a system that serves to meet economical, cultural, scientific, recreational and other human needs without safety. Safety plays an important role in sustainable development goals achievement. An essential condition of effective navigation functioning is to provide its safety. The “prescriptive” approach to the navigation safety, which is currently used in the world maritime field, is based on long-term experience and ship accidents investigation results. Thus this approach acted as an the great fact in reduction of number of accidents at sea. Having adopted the International Safety Management Code all the activities connected with navigation safety problems solution were transferred to the higher qualitative level. Search and development of new approaches and methods of ship accidents prevention during their operation have obtained greater importance. However, the maritime safety concept (i.e. the different points on ways, means and methods that should be used to achieve this goal hasn't been formed and described yet. The article contains a brief review of the main provisions of Navigation Safety Conceptions, which contribute to the number of accidents and incidents at sea reduction.
Surgical navigation with QR codes
Katanacho Manuel
2016-09-01
Full Text Available The presented work is an alternative to established measurement systems in surgical navigation. The system is based on camera based tracking of QR code markers. The application uses a single video camera, integrated in a surgical lamp, that captures the QR markers attached to surgical instruments and to the patient.
Version pressure feedback mechanisms for speculative versioning caches
Eichenberger, Alexandre E.; Gara, Alan; O& #x27; Brien, Kathryn M.; Ohmacht, Martin; Zhuang, Xiaotong
2013-03-12
Mechanisms are provided for controlling version pressure on a speculative versioning cache. Raw version pressure data is collected based on one or more threads accessing cache lines of the speculative versioning cache. One or more statistical measures of version pressure are generated based on the collected raw version pressure data. A determination is made as to whether one or more modifications to an operation of a data processing system are to be performed based on the one or more statistical measures of version pressure, the one or more modifications affecting version pressure exerted on the speculative versioning cache. An operation of the data processing system is modified based on the one or more determined modifications, in response to a determination that one or more modifications to the operation of the data processing system are to be performed, to affect the version pressure exerted on the speculative versioning cache.
Navigation system for interstitial brachytherapy
Strassmann, G.; Kolotas, C.; Heyd, R.
2000-01-01
The purpose of the stud was to develop a computed tomography (CT) based electromagnetic navigation system for interstitial brachytherapy. This is especially designed for situations when needles have to be positioned adjacent to or within critical anatomical structures. In such instances interactive 3D visualisation of the needle positions is essential. The material consisted of a Polhemus electromagnetic 3D digitizer, a Pentium 200 MHz laptop and a voice recognition for continuous speech. In addition, we developed an external reference system constructed of Perspex which could be positioned above the tumour region and attached to the patient using a non-invasive fixation method. A specially designed needle holder and patient bed were also developed. Measurements were made on a series of phantoms in order to study the efficacy and accuracy of the navigation system. The mean navigation accuracy of positioning the 20.0 cm length metallic needles within the phantoms was in the range 2.0-4.1 mm with a maximum of 5.4 mm. This is an improvement on the accuracy of a CT-guided technique which was in the range 6.1-11.3 mm with a maximum of 19.4 mm. The mean reconstruction accuracy of the implant geometry was 3.2 mm within a non-ferromagnetic environment. We found that although the needles were metallic this did not have a significant influence. We also found for our experimental setups that the CT table and operation table non-ferromagnetic parts had no significant influence on the navigation accuracy. This navigation system will be a very useful clinical tool for interstitial brachytherapy applications, particularly when critical structures have to be avoided. It also should provide a significant improvement on our existing technique
2012-07-20
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 84 and 115 [Docket No. USCG-2012-0306] RIN 1625-AB86 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments...), the Coast Guard published a final rule entitled ``Navigation and Navigable Waters; Technical...
32 CFR 644.3 - Navigation Projects.
2010-07-01
... 32 National Defense 4 2010-07-01 2010-07-01 true Navigation Projects. 644.3 Section 644.3 National... HANDBOOK Project Planning Civil Works § 644.3 Navigation Projects. (a) Land to be acquired in fee. All... construction and borrow areas. (3) In navigation-only projects, the right to permanently flood should be...
Georgy, Jacques; Noureldin, Aboelmagd
2011-01-01
Satellite navigation systems such as the global positioning system (GPS) are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS)-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF). Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF) was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D) reduced inertial sensors system (RISS) with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle's odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s) even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift, which are
Jacques Georgy
2011-04-01
Full Text Available Satellite navigation systems such as the global positioning system (GPS are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF. Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D reduced inertial sensors system (RISS with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle’s odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift
Theoretical Limits of Lunar Vision Aided Navigation with Inertial Navigation System
2015-03-26
THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones, Capt, USAF AFIT-ENG-MS-15-M-020 DEPARTMENT...Government and is not subject to copyright protection in the United States. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH...DISTRIBUTION UNLIMITED. AFIT-ENG-MS-15-M-020 THEORETICAL LIMITS OF LUNAR VISION AIDED NAVIGATION WITH INERTIAL NAVIGATION SYSTEM THESIS David W. Jones
Development of field navigation system; Field navigation system no kaihatsu
Ibara, S; Minode, M; Nishioka, K [Daihatsu Motor Co. Ltd., Osaka (Japan)
1995-04-20
This paper describes the following matters on a field navigation system developed for the purpose of covering a field of several kilometer square. This system consists of a center system and a vehicle system, and the center system comprises a map information computer and a communication data controlling computer; since the accuracy for a vehicle position detected by a GPS is not sufficient, an attempt of increasing the accuracy of vehicle position detection is made by means of a hybrid system; the hybrid system uses a satellite navigation method of differential system in which the error components in the GPS are transmitted from the center, and also uses a self-contained navigation method which performs an auxiliary function when the accuracy in the GPS has dropped; corrected GPS values, emergency messages to all of the vehicles and data of each vehicle position are communicated by wireless transmission in two ways between the center and vehicles; and accommodation of the map data adopted a system that can respond quickly to any change in roads and facilities. 3 refs., 13 figs., 1 tab.
Determining Optimal Decision Version
Olga Ioana Amariei
2014-06-01
Full Text Available In this paper we start from the calculation of the product cost, applying the method of calculating the cost of hour- machine (THM, on each of the three cutting machines, namely: the cutting machine with plasma, the combined cutting machine (plasma and water jet and the cutting machine with a water jet. Following the calculation of cost and taking into account the precision of manufacturing of each machine, as well as the quality of the processed surface, the optimal decisional version needs to be determined regarding the product manufacturing. To determine the optimal decisional version, we resort firstly to calculating the optimal version on each criterion, and then overall using multiattribute decision methods.
Heinicke, P.; Berg, D.; Constanta-Fanourakis, P.; Quigg, E.K.
1985-01-01
MULTI is a general purpose, high speed, high energy physics interface to data acquisition and data investigation system that runs on PDP-11 and VAX architecture. This paper describes the latest version of MULTI, which runs under RSX-11M version 4.1 and supports a modular approach to the separate tasks that interface to it, allowing the same system to be used in single CPU test beam experiments as well as multiple interconnected CPU, large scale experiments. MULTI uses CAMAC (IEE-583) for control and monitoring of an experiment, and is written in FORTRAN-77 and assembler. The design of this version, which simplified the interface between tasks, and eliminated the need for a hard to maintain homegrown I/O system is also discussed
Linear Covariance Analysis for a Lunar Lander
Jang, Jiann-Woei; Bhatt, Sagar; Fritz, Matthew; Woffinden, David; May, Darryl; Braden, Ellen; Hannan, Michael
2017-01-01
A next-generation lunar lander Guidance, Navigation, and Control (GNC) system, which includes a state-of-the-art optical sensor suite, is proposed in a concept design cycle. The design goal is to allow the lander to softly land within the prescribed landing precision. The achievement of this precision landing requirement depends on proper selection of the sensor suite. In this paper, a robust sensor selection procedure is demonstrated using a Linear Covariance (LinCov) analysis tool developed by Draper.
Versioning of printed products
Tuijn, Chris
2005-01-01
During the definition of a printed product in an MIS system, a lot of attention is paid to the production process. The MIS systems typically gather all process-related parameters at such a level of detail that they can determine what the exact cost will be to make a specific product. This information can then be used to make a quote for the customer. Considerably less attention is paid to the content of the products since this does not have an immediate impact on the production costs (assuming that the number of inks or plates is known in advance). The content management is typically carried out either by the prepress systems themselves or by dedicated workflow servers uniting all people that contribute to the manufacturing of a printed product. Special care must be taken when considering versioned products. With versioned products we here mean distinct products that have a number of pages or page layers in common. Typical examples are comic books that have to be printed in different languages. In this case, the color plates can be shared over the different versions and the black plate will be different. Other examples are nation-wide magazines or newspapers that have an area with regional pages or advertising leaflets in different languages or currencies. When considering versioned products, the content will become an important cost factor. First of all, the content management (and associated proofing and approval cycles) becomes much more complex and, therefore, the risk that mistakes will be made increases considerably. Secondly, the real production costs are very much content-dependent because the content will determine whether plates can be shared across different versions or not and how many press runs will be needed. In this paper, we will present a way to manage different versions of a printed product. First, we will introduce a data model for version management. Next, we will show how the content of the different versions can be supplied by the customer
Makino, Kyoko; Berz, Martin
2006-01-01
In this paper, we review the features in the newly released version of COSY INFINITY, which currently has a base of more than 1000 registered users, focusing on the topics which are new and some topics which became available after the first release of the previous versions 8 and 8.1. The recent main enhancements of the code are devoted to reliability and efficiency of the computation, to verified integration, and to rigorous global optimization. There are various data types available in COSY INFINITY to support these goals, and the paper also reviews the feature and usage of those data types
Autonomous Robot Navigation based on Visual Landmarks
Livatino, Salvatore
2005-01-01
The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully a...... automatically learn and store visual landmarks, and later recognize these landmarks from arbitrary positions and thus estimate robot position and heading.......The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully...... autonomous navigation and self-localization using automatically selected landmarks. The thesis investigates autonomous robot navigation and proposes a new method which benefits from the potential of the visual sensor to provide accuracy and reliability to the navigation process while relying on naturally...
Observability during planetary approach navigation
Bishop, Robert H.; Burkhart, P. Daniel; Thurman, Sam W.
1993-01-01
The objective of the research is to develop an analytic technique to predict the relative navigation capability of different Earth-based radio navigation measurements. In particular, the problem is to determine the relative ability of geocentric range and Doppler measurements to detect the effects of the target planet gravitational attraction on the spacecraft during the planetary approach and near-encounter mission phases. A complete solution to the two-dimensional problem has been developed. Relatively simple analytic formulas are obtained for range and Doppler measurements which describe the observability content of the measurement data along the approach trajectories. An observability measure is defined which is based on the observability matrix for nonlinear systems. The results show good agreement between the analytic observability analysis and the computational batch processing method.
Navigating the Internet of Things
Rassia, Stamatina; Steiner, Henriette
2017-01-01
Navigating the Internet of Things is an exploration of interconnected objects, functions, and situations in networks created to ease and manage our daily lives. The Internet of Things represents semi-automated interconnections of different objects in a network based on different information...... technologies. Some examples of this are presented here in order to better understand, explain, and discuss the elements that compose the Internet of Things. In this chapter, we provide a theoretical and practical perspective on both the micro- and macro-scales of ‘things’ (objects), small and large (e.......g. computers or interactive maps), that suggest new topographic relationships and challenge our understanding of users’ involvement with a given technology against the semi-automated workings of these systems. We navigate from a philosophical enquiry into the ‘thingness of things’ dating from the 1950s...
Korthauer, L E; Nowak, N T; Frahmand, M; Driscoll, I
2017-01-15
Although effective spatial navigation requires memory for objects and locations, navigating a novel environment may also require considerable executive resources. The present study investigated associations between performance on the virtual Morris Water Task (vMWT), an analog version of a nonhuman spatial navigation task, and neuropsychological tests of executive functioning and spatial performance in 75 healthy young adults. More effective vMWT performance (e.g., lower latency and distance to reach hidden platform, greater distance in goal quadrant on a probe trial, fewer path intersections) was associated with better verbal fluency, set switching, response inhibition, and ability to mentally rotate objects. Findings also support a male advantage in spatial navigation, with sex moderating several associations between vMWT performance and executive abilities. Overall, we report a robust relationship between executive functioning and navigational skill, with some evidence that men and women may differentially recruit cognitive abilities when navigating a novel environment. Copyright © 2016 Elsevier B.V. All rights reserved.
A Bionic Polarization Navigation Sensor and Its Calibration Method.
Zhao, Huijie; Xu, Wujian
2016-08-03
The polarization patterns of skylight which arise due to the scattering of sunlight in the atmosphere can be used by many insects for deriving compass information. Inspired by insects' polarized light compass, scientists have developed a new kind of navigation method. One of the key techniques in this method is the polarimetric sensor which is used to acquire direction information from skylight. In this paper, a polarization navigation sensor is proposed which imitates the working principles of the polarization vision systems of insects. We introduce the optical design and mathematical model of the sensor. In addition, a calibration method based on variable substitution and non-linear curve fitting is proposed. The results obtained from the outdoor experiments provide support for the feasibility and precision of the sensor. The sensor's signal processing can be well described using our mathematical model. A relatively high degree of accuracy in polarization measurement can be obtained without any error compensation.
Navigation in diagnosis and therapy
Vannier, Michael W.; Haller, John W.
1999-01-01
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
Navigation Strategies for Primitive Solar System Body Rendezvous and Proximity Operations
Getzandanner, Kenneth M.
2011-01-01
A wealth of scientific knowledge regarding the composition and evolution of the solar system can be gained through reconnaissance missions to primitive solar system bodies. This paper presents analysis of a baseline navigation strategy designed to address the unique challenges of primitive body navigation. Linear covariance and Monte Carlo error analysis was performed on a baseline navigation strategy using simulated data from a· design reference mission (DRM). The objective of the DRM is to approach, rendezvous, and maintain a stable orbit about the near-Earth asteroid 4660 Nereus. The outlined navigation strategy and resulting analyses, however, are not necessarily limited to this specific target asteroid as they may he applicable to a diverse range of mission scenarios. The baseline navigation strategy included simulated data from Deep Space Network (DSN) radiometric tracking and optical image processing (OpNav). Results from the linear covariance and Monte Carlo analyses suggest the DRM navigation strategy is sufficient to approach and perform proximity operations in the vicinity of the target asteroid with meter-level accuracy.
Recent Updates to the GEOS-5 Linear Model
Holdaway, Dan; Kim, Jong G.; Errico, Ron; Gelaro, Ronald; Mahajan, Rahul
2014-01-01
Global Modeling and Assimilation Office (GMAO) is close to having a working 4DVAR system and has developed a linearized version of GEOS-5.This talk outlines a series of improvements made to the linearized dynamics, physics and trajectory.Of particular interest is the development of linearized cloud microphysics, which provides the framework for 'all-sky' data assimilation.
Vision Based Navigation for Autonomous Cooperative Docking of CubeSats
Pirat, Camille; Ankersen, Finn; Walker, Roger; Gass, Volker
2018-05-01
A realistic rendezvous and docking navigation solution applicable to CubeSats is investigated. The scalability analysis of the ESA Autonomous Transfer Vehicle Guidance, Navigation & Control (GNC) performances and the Russian docking system, shows that the docking of two CubeSats would require a lateral control performance of the order of 1 cm. Line of sight constraints and multipath effects affecting Global Navigation Satellite System (GNSS) measurements in close proximity prevent the use of this sensor for the final approach. This consideration and the high control accuracy requirement led to the use of vision sensors for the final 10 m of the rendezvous and docking sequence. A single monocular camera on the chaser satellite and various sets of Light-Emitting Diodes (LEDs) on the target vehicle ensure the observability of the system throughout the approach trajectory. The simple and novel formulation of the measurement equations allows differentiating unambiguously rotations from translations between the target and chaser docking port and allows a navigation performance better than 1 mm at docking. Furthermore, the non-linear measurement equations can be solved in order to provide an analytic navigation solution. This solution can be used to monitor the navigation filter solution and ensure its stability, adding an extra layer of robustness for autonomous rendezvous and docking. The navigation filter initialization is addressed in detail. The proposed method is able to differentiate LEDs signals from Sun reflections as demonstrated by experimental data. The navigation filter uses a comprehensive linearised coupled rotation/translation dynamics, describing the chaser to target docking port motion. The handover, between GNSS and vision sensor measurements, is assessed. The performances of the navigation function along the approach trajectory is discussed.
BLAS- BASIC LINEAR ALGEBRA SUBPROGRAMS
Krogh, F. T.
1994-01-01
The Basic Linear Algebra Subprogram (BLAS) library is a collection of FORTRAN callable routines for employing standard techniques in performing the basic operations of numerical linear algebra. The BLAS library was developed to provide a portable and efficient source of basic operations for designers of programs involving linear algebraic computations. The subprograms available in the library cover the operations of dot product, multiplication of a scalar and a vector, vector plus a scalar times a vector, Givens transformation, modified Givens transformation, copy, swap, Euclidean norm, sum of magnitudes, and location of the largest magnitude element. Since these subprograms are to be used in an ANSI FORTRAN context, the cases of single precision, double precision, and complex data are provided for. All of the subprograms have been thoroughly tested and produce consistent results even when transported from machine to machine. BLAS contains Assembler versions and FORTRAN test code for any of the following compilers: Lahey F77L, Microsoft FORTRAN, or IBM Professional FORTRAN. It requires the Microsoft Macro Assembler and a math co-processor. The PC implementation allows individual arrays of over 64K. The BLAS library was developed in 1979. The PC version was made available in 1986 and updated in 1988.
Linear Algebra and Smarandache Linear Algebra
Vasantha, Kandasamy
2003-01-01
The present book, on Smarandache linear algebra, not only studies the Smarandache analogues of linear algebra and its applications, it also aims to bridge the need for new research topics pertaining to linear algebra, purely in the algebraic sense. We have introduced Smarandache semilinear algebra, Smarandache bilinear algebra and Smarandache anti-linear algebra and their fuzzy equivalents. Moreover, in this book, we have brought out the study of linear algebra and vector spaces over finite p...
Intraoperative CT navigation for glenoid component fixation in reverse shoulder arthroplasty
Ashok S Gavaskar
2013-01-01
Full Text Available CT navigation has been shown to improve component positioning in total shoulder arthroplasty. The technique can be useful in achieving strong initial fixation of the metal backed glenoid in reverse shoulder arthroplasty. We report a 61 years male patient who underwent reverse shoulder arthroplasty for rotator cuff arthropathy. CT navigation was used intraoperatively to identify best possible glenoid bone and to maximize the depth of the fixation screws that anchor the metaglene portion of the metal backed glenoid component. Satisfactory positioning of screws and component was achieved without any perforation or iatrogenic fracture in the scapula. CT navigation can help in maximizing the purchase of the fixation screws that dictate the initial stability of the glenoid component in reverse shoulder arthroplasty. The technique can be extended to improve glenoid component position [version and tilt] with the availability of appropriate software.
Global Historical Climatology Network (GHCN), Version 1 (Version Superseded)
National Oceanic and Atmospheric Administration, Department of Commerce — Please note, this dataset has been superseded by a newer version (see below). Users should not use this version except in rare cases (e.g., when reproducing previous...
Makino, Kyoko; Berz, Martin
1999-01-01
The latest version of the particle optics code COSY INFINITY is presented. Using Differential Algebraic (DA) methods, the code allows the computation of aberrations of arbitrary field arrangements to in principle unlimited order. Besides providing a general overview of the code, several recent techniques developed for specific applications are highlighted. These include new features for the direct utilization of detailed measured fields as well as rigorous treatment of remainder bounds
Allensworth, J.A.
1984-04-01
EASI (Estimate of Adversary Sequence Interruption) is an analytical technique for measuring the effectiveness of physical protection systems. EASI Graphics is a computer graphics extension of EASI which provides a capability for performing sensitivity and trade-off analyses of the parameters of a physical protection system. This document reports on the implementation of the Version II of EASI Graphics and illustrates its application with some examples. 5 references, 15 figures, 6 tables
Emergency navigation without an infrastructure.
Gelenbe, Erol; Bi, Huibo
2014-08-18
Emergency navigation systems for buildings and other built environments, such as sport arenas or shopping centres, typically rely on simple sensor networks to detect emergencies and, then, provide automatic signs to direct the evacuees. The major drawbacks of such static wireless sensor network (WSN)-based emergency navigation systems are the very limited computing capacity, which makes adaptivity very difficult, and the restricted battery power, due to the low cost of sensor nodes for unattended operation. If static wireless sensor networks and cloud-computing can be integrated, then intensive computations that are needed to determine optimal evacuation routes in the presence of time-varying hazards can be offloaded to the cloud, but the disadvantages of limited battery life-time at the client side, as well as the high likelihood of system malfunction during an emergency still remain. By making use of the powerful sensing ability of smart phones, which are increasingly ubiquitous, this paper presents a cloud-enabled indoor emergency navigation framework to direct evacuees in a coordinated fashion and to improve the reliability and resilience for both communication and localization. By combining social potential fields (SPF) and a cognitive packet network (CPN)-based algorithm, evacuees are guided to exits in dynamic loose clusters. Rather than relying on a conventional telecommunications infrastructure, we suggest an ad hoc cognitive packet network (AHCPN)-based protocol to adaptively search optimal communication routes between portable devices and the network egress nodes that provide access to cloud servers, in a manner that spares the remaining battery power of smart phones and minimizes the time latency. Experimental results through detailed simulations indicate that smart human motion and smart network management can increase the survival rate of evacuees and reduce the number of drained smart phones in an evacuation process.
Emergency Navigation without an Infrastructure
Erol Gelenbe
2014-08-01
Full Text Available Emergency navigation systems for buildings and other built environments, such as sport arenas or shopping centres, typically rely on simple sensor networks to detect emergencies and, then, provide automatic signs to direct the evacuees. The major drawbacks of such static wireless sensor network (WSN-based emergency navigation systems are the very limited computing capacity, which makes adaptivity very difficult, and the restricted battery power, due to the low cost of sensor nodes for unattended operation. If static wireless sensor networks and cloud-computing can be integrated, then intensive computations that are needed to determine optimal evacuation routes in the presence of time-varying hazards can be offloaded to the cloud, but the disadvantages of limited battery life-time at the client side, as well as the high likelihood of system malfunction during an emergency still remain. By making use of the powerful sensing ability of smart phones, which are increasingly ubiquitous, this paper presents a cloud-enabled indoor emergency navigation framework to direct evacuees in a coordinated fashion and to improve the reliability and resilience for both communication and localization. By combining social potential fields (SPF and a cognitive packet network (CPN-based algorithm, evacuees are guided to exits in dynamic loose clusters. Rather than relying on a conventional telecommunications infrastructure, we suggest an ad hoc cognitive packet network (AHCPN-based protocol to adaptively search optimal communication routes between portable devices and the network egress nodes that provide access to cloud servers, in a manner that spares the remaining battery power of smart phones and minimizes the time latency. Experimental results through detailed simulations indicate that smart human motion and smart network management can increase the survival rate of evacuees and reduce the number of drained smart phones in an evacuation process.
CLIC brochure (English version)
Lefevre, Christiane
2012-01-01
The world's biggest and most powerful accelerator, the LHC, is mapping the route of particle physics for the future. The next step, to complement the LHC in exploring this new region, is most likely to be a linear electron-positron collider. The Compact Linear Collider (CLIC) is a novel approach to such a collider. It is currently under development by the CLIC collaboration, which is hosted at CERN.
Chemical compass for bird navigation
Solov'yov, Ilia; Hore, Peter J.; Ritz, Thorsten
2014-01-01
Migratory birds travel spectacular distances each year, navigating and orienting by a variety of means, most of which are poorly understood. Among them is a remarkable ability to perceive the intensity and direction of the Earth's magnetic field. Biologically credible mechanisms for the detection...... increased interest following the proposal in 2000 that free radical chemistry could occur in the bird's retina initiated by photoexcitation of cryptochrome, a specialized photoreceptor protein. In the present paper we review the important physical and chemical constraints on a possible radical...
Robotics_MobileRobot Navigation, Phase I
National Aeronautics and Space Administration — Robots and rovers exploring planets need to autonomously navigate to specified locations. Advanced Scientific Concepts, Inc. (ASC) and the University of Minnesota...
Applications of navigation for orthognathic surgery.
Bobek, Samuel L
2014-11-01
Stereotactic surgical navigation has been used in oral and maxillofacial surgery for orbital reconstruction, reduction of facial fractures, localization of foreign bodies, placement of implants, skull base surgery, tumor removal, temporomandibular joint surgery, and orthognathic surgery. The primary goals in adopting intraoperative navigation into these different surgeries were to define and localize operative anatomy, to localize implant position, and to orient the surgical wound. Navigation can optimize the functional and esthetic outcomes in patients with dentofacial deformities by identifying pertinent anatomic structures, transferring the surgical plan to the patient, and verifying the surgical result. This article discusses the principles of navigation-guided orthognathic surgery. Copyright © 2014 Elsevier Inc. All rights reserved.
Airports and Navigation Aids Database System -
Department of Transportation — Airport and Navigation Aids Database System is the repository of aeronautical data related to airports, runways, lighting, NAVAID and their components, obstacles, no...
Condiment: general synthesis of different versions
Mangin, J.P.
1990-01-01
CONDIMENT is a code for the computation of ion migration and diffusion in areas close to radwaste storage facilities. This type of application was found to require a mesh pattern and boundary conditions different from the usual, which justifies the writing of a new code. A first version (version 2) only convers the migration of a single, non radioactive ion. The discretization, the selection of an implicit scheme, and the various boundary conditions are described. Physical quantities such as diffusion coefficient, porosity, retardation factor and permeability vary in space but not in time. A first extension consists of taking consideration radioactivity and filiation. Discretization with respect to time is modified, and a check performed on the original analytical solutions. In a second extension, consideration is given to non-linear adsorption, which makes it necessary to use the NEWTON-RAPHSON method. One can thus modelize the FREUNDLICH isotherms, in spite of the singular point at the origin. Diffusion, apparent porosity and permeability values can be changed as computed proceeds. The last extension is the introduction of two ions with the formation of precipitate. The formulation is derived from that used for non-linear adsorption, the precipitate playing a part similar to that of adsorbed concentration. Agreement with the original analytical solutions is verified. The case of migration with several interacting ions is approached from the theoretical standpoint. We described the discretization, which is similar to that in the first version, but involves many additional variables. Numerical stability is shown to be unconditional [fr
Burin, Debora I.; Barreyro, Juan P.; Saux, Gastón; Irrazábal, Natalia C.
2015-01-01
Introduction: In contemporary information societies, reading digital text has become pervasive. One of the most distinctive features of digital texts is their internal connections via hyperlinks, resulting in non-linear hypertexts. Hypertext structure and previous knowledge affect navigation and comprehension of digital expository texts. From the…
Youth Mobilisation as Social Navigation
Vigh, Henrik Erdman
2010-01-01
ties and options that arise in such situations. Building on the Guinean Creole term of dubriagem, the article proposes the concept of social navigation as an analytical optic able to shed light on praxis in unstable environments. The concept of social navigation makes it possible to focus on the way we move within changing social environments. It is processuality squared, illuminating motion within motion. The article thus advocates an analysis of praxis that takes its point of departure in a Batesonian and intermorphological understanding of action in order to further our understanding of the acts of youth in conflict....
Ultra-Wideband Tracking System Design for Relative Navigation
Ni, Jianjun David; Arndt, Dickey; Bgo, Phong; Dekome, Kent; Dusl, John
2011-01-01
This presentation briefly discusses a design effort for a prototype ultra-wideband (UWB) time-difference-of-arrival (TDOA) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being designed for use in localization and navigation of a rover in a GPS deprived environment for surface missions. In one application enabled by the UWB tracking, a robotic vehicle carrying equipments can autonomously follow a crewed rover from work site to work site such that resources can be carried from one landing mission to the next thereby saving up-mass. The UWB Systems Group at JSC has developed a UWB TDOA High Resolution Proximity Tracking System which can achieve sub-inch tracking accuracy of a target within the radius of the tracking baseline [1]. By extending the tracking capability beyond the radius of the tracking baseline, a tracking system is being designed to enable relative navigation between two vehicles for surface missions. A prototype UWB TDOA tracking system has been designed, implemented, tested, and proven feasible for relative navigation of robotic vehicles. Future work includes testing the system with the application code to increase the tracking update rate and evaluating the linear tracking baseline to improve the flexibility of antenna mounting on the following vehicle.
Off the Beaten tracks: Exploring Three Aspects of Web Navigation
Weinreich, H.; Obendorf, H.; Herder, E.; Mayer, M.; Edmonds, H.; Hawkey, K.; Kellar, M.; Turnbull, D.
2006-01-01
This paper presents results of a long-term client-side Web usage study, updating previous studies that range in age from five to ten years. We focus on three aspects of Web navigation: changes in the distribution of navigation actions, speed of navigation and within-page navigation. “Navigation
Menu-Driven Solver Of Linear-Programming Problems
Viterna, L. A.; Ferencz, D.
1992-01-01
Program assists inexperienced user in formulating linear-programming problems. A Linear Program Solver (ALPS) computer program is full-featured LP analysis program. Solves plain linear-programming problems as well as more-complicated mixed-integer and pure-integer programs. Also contains efficient technique for solution of purely binary linear-programming problems. Written entirely in IBM's APL2/PC software, Version 1.01. Packed program contains licensed material, property of IBM (copyright 1988, all rights reserved).
The Unified Extensional Versioning Model
Asklund, U.; Bendix, Lars Gotfred; Christensen, H. B.
1999-01-01
Versioning of components in a system is a well-researched field where various adequate techniques have already been established. In this paper, we look at how versioning can be extended to cover also the structural aspects of a system. There exist two basic techniques for versioning - intentional...
Dobos, A. P.
2014-09-01
The NREL PVWatts calculator is a web application developed by the National Renewable Energy Laboratory (NREL) that estimates the electricity production of a grid-connected photovoltaic system based on a few simple inputs. PVWatts combines a number of sub-models to predict overall system performance, and makes includes several built-in parameters that are hidden from the user. This technical reference describes the sub-models, documents assumptions and hidden parameters, and explains the sequence of calculations that yield the final system performance estimate. This reference is applicable to the significantly revised version of PVWatts released by NREL in 2014.
Aggarwal, Priyanka; Syed, Zainab; El-Sheimy, Naser
2009-01-01
Navigation includes the integration of methodologies and systems for estimating time-varying position, velocity and attitude of moving objects. Navigation incorporating the integrated inertial navigation system (INS) and global positioning system (GPS) generally requires extensive evaluations of nonlinear equations involving double integration. Currently, integrated navigation systems are commonly implemented using the extended Kalman filter (EKF). The EKF assumes a linearized process, measurement models and Gaussian noise distributions. These assumptions are unrealistic for highly nonlinear systems like land vehicle navigation and may cause filter divergence. A particle filter (PF) is developed to enhance integrated INS/GPS system performance as it can easily deal with nonlinearity and non-Gaussian noises. In this paper, a hybrid extended particle filter (HEPF) is developed as an alternative to the well-known EKF to achieve better navigation data accuracy for low-cost microelectromechanical system sensors. The results show that the HEPF performs better than the EKF during GPS outages, especially when simulated outages are located in periods with high vehicle dynamics
Lesions of the basal forebrain cholinergic system in mice disrupt idiothetic navigation.
Adam S Hamlin
Full Text Available Loss of integrity of the basal forebrain cholinergic neurons is a consistent feature of Alzheimer's disease, and measurement of basal forebrain degeneration by magnetic resonance imaging is emerging as a sensitive diagnostic marker for prodromal disease. It is also known that Alzheimer's disease patients perform poorly on both real space and computerized cued (allothetic or uncued (idiothetic recall navigation tasks. Although the hippocampus is required for allothetic navigation, lesions of this region only mildly affect idiothetic navigation. Here we tested the hypothesis that the cholinergic medial septo-hippocampal circuit is important for idiothetic navigation. Basal forebrain cholinergic neurons were selectively lesioned in mice using the toxin saporin conjugated to a basal forebrain cholinergic neuronal marker, the p75 neurotrophin receptor. Control animals were able to learn and remember spatial information when tested on a modified version of the passive place avoidance test where all extramaze cues were removed, and animals had to rely on idiothetic signals. However, the exploratory behaviour of mice with cholinergic basal forebrain lesions was highly disorganized during this test. By contrast, the lesioned animals performed no differently from controls in tasks involving contextual fear conditioning and spatial working memory (Y maze, and displayed no deficits in potentially confounding behaviours such as motor performance, anxiety, or disturbed sleep/wake cycles. These data suggest that the basal forebrain cholinergic system plays a specific role in idiothetic navigation, a modality that is impaired early in Alzheimer's disease.
Rudyk A.V.
2016-12-01
Full Text Available The article describes methods of constructing devices for measuring the capacitance of micromechanical sensors (accelerometers and gyros mobile robots navigation systems and its deviation from the nominal value. A modified diagram of a sigma-delta modulator is offered. It realizes a direct connection capacitive sensor connection to the sigma-delta converter, as a result increased resolution, accuracy and linearity of the conversion. This interface is insensitive to the value of capacitance between the sensor leads and common wire or leakage current to a common wire. Variants of expansion as the nominal of the test capacity and the range of conversion of the relative deviation of the nominal capacity using two integrators are offered. The versions of circuit implementation devices for measuring the capacitance deviation of a micromechanical sensor from the nominal value are designed on the basis of the completed integrated circuit AD7745 / AD7746 and AD7747 of Analog Devices, CAV414 / 424 firm Analog Microelectronics and precision analog microcontroller ADuCM360 / CM361 company ARM Limited.
Vibrotactile in-vehicle navigation system
Erp, J.B.F. van; Veen, H.J. van
2004-01-01
A vibrotactile display, consisting ofeight vibrating elements or tactors mounted in a driver's seat, was tested in a driving simulator. Participants drove with visual, tactile and multimodal navigation displays through a built-up area. Workload and the reaction time to navigation messages were
Parsimonious Ways to Use Vision for Navigation
Paul Graham
2012-05-01
Full Text Available The use of visual information for navigation appears to be a universal strategy for sighted animals, amongst which, one particular group of expert navigators are the ants. The broad interest in studies of ant navigation is in part due to their small brains, thus biomimetic engineers expect to be impressed by elegant control solutions, and psychologists might hope for a description of the minimal cognitive requirements for complex spatial behaviours. In this spirit, we have been taking an interdisciplinary approach to the visual guided navigation of ants in their natural habitat. Behavioural experiments and natural image statistics show that visual navigation need not depend on the remembering or recognition of objects. Further modelling work suggests how simple behavioural routines might enable navigation using familiarity detection rather than explicit recall, and we present a proof of concept that visual navigation using familiarity can be achieved without specifying when or what to learn, nor separating routes into sequences of waypoints. We suggest that our current model represents the only detailed and complete model of insect route guidance to date. What's more, we believe the suggested mechanisms represent useful parsimonious hypotheses for the visually guided navigation in larger-brain animals.
A Semantic Navigation Model for Video Games
van Driel, Leonard; Bidarra, Rafael
Navigational performance of artificial intelligence (AI) characters in computer games is gaining an increasingly important role in the perception of their behavior. While recent games successfully solve some complex navigation problems, there is little known or documented on the underlying approaches, often resembling a primitive conglomerate of ad-hoc algorithms for specific situations.
Sex differences in navigation strategy and efficiency.
Boone, Alexander P; Gong, Xinyi; Hegarty, Mary
2018-05-22
Research on human navigation has indicated that males and females differ in self-reported navigation strategy as well as objective measures of navigation efficiency. In two experiments, we investigated sex differences in navigation strategy and efficiency using an objective measure of strategy, the dual-solution paradigm (DSP; Marchette, Bakker, & Shelton, 2011). Although navigation by shortcuts and learned routes were the primary strategies used in both experiments, as in previous research on the DSP, individuals also utilized route reversals and sometimes found the goal location as a result of wandering. Importantly, sex differences were found in measures of both route selection and navigation efficiency. In particular, males were more likely to take shortcuts and reached their goal location faster than females, while females were more likely to follow learned routes and wander. Self-report measures of strategy were only weakly correlated with objective measures of strategy, casting doubt on their usefulness. This research indicates that the sex difference in navigation efficiency is large, and only partially related to an individual's navigation strategy as measured by the dual-solution paradigm.
Navigator. Volume 45, Number 2, Winter 2009
National Science Education Leadership Association, 2009
2009-01-01
The National Science Education Leadership Association (NSELA) was formed in 1959 to meet a need to develop science education leadership for K-16 school systems. "Navigator" is published by NSELA to provide the latest NSELA events. This issue of "Navigator" contains the following reports: (1) A Message from the President: Creating Networks of…
Navigator. Volume 45, Number 3, Spring 2009
National Science Education Leadership Association, 2009
2009-01-01
The National Science Education Leadership Association (NSELA) was formed in 1959 to meet a need to develop science education leadership for K-16 school systems. "Navigator" is published by NSELA to provide the latest NSELA events. This issue of "Navigator" includes the following items: (1) A Message from the President (Brenda Wojnowski); (2) NSELA…
Natural Language Navigation Support in Virtual Reality
van Luin, J.; Nijholt, Antinus; op den Akker, Hendrikus J.A.; Giagourta, V.; Strintzis, M.G.
2001-01-01
We describe our work on designing a natural language accessible navigation agent for a virtual reality (VR) environment. The agent is part of an agent framework, which means that it can communicate with other agents. Its navigation task consists of guiding the visitors in the environment and to
Risk management model of winter navigation operations
Valdez Banda, Osiris A.; Goerlandt, Floris; Kuzmin, Vladimir; Kujala, Pentti; Montewka, Jakub
2016-01-01
The wintertime maritime traffic operations in the Gulf of Finland are managed through the Finnish–Swedish Winter Navigation System. This establishes the requirements and limitations for the vessels navigating when ice covers this area. During winter navigation in the Gulf of Finland, the largest risk stems from accidental ship collisions which may also trigger oil spills. In this article, a model for managing the risk of winter navigation operations is presented. The model analyses the probability of oil spills derived from collisions involving oil tanker vessels and other vessel types. The model structure is based on the steps provided in the Formal Safety Assessment (FSA) by the International Maritime Organization (IMO) and adapted into a Bayesian Network model. The results indicate that ship independent navigation and convoys are the operations with higher probability of oil spills. Minor spills are most probable, while major oil spills found very unlikely but possible. - Highlights: •A model to assess and manage the risk of winter navigation operations is proposed. •The risks of oil spills in winter navigation in the Gulf of Finland are analysed. •The model assesses and prioritizes actions to control the risk of the operations. •The model suggests navigational training as the most efficient risk control option.
The Navigation Metaphor in Security Economics
Pieters, Wolter; Barendse, Jeroen; Ford, Margaret
2016-01-01
The navigation metaphor for cybersecurity merges security architecture models and security economics. By identifying the most efficient routes for gaining access to assets from an attacker's viewpoint, an organization can optimize its defenses along these routes. The well-understood concept of na...... of navigation makes it easier to motivate and explain security investment to a wide audience, encouraging strategic security decisions....
Evolved Navigation Theory and Horizontal Visual Illusions
Jackson, Russell E.; Willey, Chela R.
2011-01-01
Environmental perception is prerequisite to most vertebrate behavior and its modern investigation initiated the founding of experimental psychology. Navigation costs may affect environmental perception, such as overestimating distances while encumbered (Solomon, 1949). However, little is known about how this occurs in real-world navigation or how…
Rosetta Star Tracker and Navigation Camera
Thuesen, Gøsta
1998-01-01
Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera.......Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera....
Medical Service
2002-01-01
The table of emergency numbers that appeared in Bulletin 10/2002 is out of date. The updated version provided by the Medical Service appears on the following page. Please disregard the previous version. URGENT NEED OF A DOCTOR GENEVAPATIENT NOT FIT TO BE MOVED: Call your family doctor Or SOS MEDECINS (24H/24H) 748 49 50 Or ASSOC. OF GENEVA DOCTORS (7H-23H) 322 20 20 PATIENT CAN BE MOVED: HOPITAL CANTONAL 24 Micheli du Crest 372 33 11 382 33 11 CHILDREN'S HOSPITAL 6 rue Willy Donzé 382 68 18 382 45 55 MATERNITY 24 Micheli du Crest 382 68 16 382 33 11 OPHTALMOLOGY 22 Alcide Jentzer 382 84 00 HOPITAL DE LA TOUR Meyrin 719 61 11 CENTRE MEDICAL DE MEYRIN Champs Fréchets 719 74 00 URGENCES : FIRE BRIGADE 118 FIRE BRIGADE CERN 767 44 44 BESOIN URGENT D'AMBULANCE (GENEVE ET VAUD) : 144 POLICE 117 ANTI-POISON CENTRE 24H/24H 01 251 51 510 EUROPEAN EMERGENCY CALL: 112 FRANCE PATIENT NOT FIT TO BE MOVED: call your family doctor PATIENT CAN BE MOVED: ST. JULIE...
Quantum imaging for underwater arctic navigation
Lanzagorta, Marco
2017-05-01
The precise navigation of underwater vehicles is a difficult task due to the challenges imposed by the variable oceanic environment. It is particularly difficult if the underwater vehicle is trying to navigate under the Arctic ice shelf. Indeed, in this scenario traditional navigation devices such as GPS, compasses and gyrocompasses are unavailable or unreliable. In addition, the shape and thickness of the ice shelf is variable throughout the year. Current Arctic underwater navigation systems include sonar arrays to detect the proximity to the ice. However, these systems are undesirable in a wartime environment, as the sound gives away the position of the underwater vehicle. In this paper we briefly describe the theoretical design of a quantum imaging system that could allow the safe and stealthy navigation of underwater Arctic vehicles.
Ethical Navigation in Leadership Training
Øyvind Kvalnes
2012-05-01
Full Text Available Business leaders frequently face dilemmas, circumstances where whatever course of action they choose, something of important value will be offended. How can an organisation prepare its decision makers for such situations? This article presents a pedagogical approach to dilemma training for business leaders and managers. It has evolved through ten years of experience with human resource development, where ethics has been an integral part of programs designed to help individuals to become excellent in their professional roles. The core element in our approach is The Navigation Wheel, a figure used to keep track of relevant decision factors. Feedback from participants indicates that dilemma training has helped them to recognise the ethical dimension of leadership. They respond that the tools and concepts are highly relevant in relation to the challenges that occur in the working environment they return to after leadership training.http://dx.doi.org/10.5324/eip.v6i1.1778
Autonomous navigation system and method
Bruemmer, David J [Idaho Falls, ID; Few, Douglas A [Idaho Falls, ID
2009-09-08
A robot platform includes perceptors, locomotors, and a system controller, which executes instructions for autonomously navigating a robot. The instructions repeat, on each iteration through an event timing loop, the acts of defining an event horizon based on the robot's current velocity, detecting a range to obstacles around the robot, testing for an event horizon intrusion by determining if any range to the obstacles is within the event horizon, and adjusting rotational and translational velocity of the robot accordingly. If the event horizon intrusion occurs, rotational velocity is modified by a proportion of the current rotational velocity reduced by a proportion of the range to the nearest obstacle and translational velocity is modified by a proportion of the range to the nearest obstacle. If no event horizon intrusion occurs, translational velocity is set as a ratio of a speed factor relative to a maximum speed.
Non-Linear Fibres for Widely Tunable Femtosecond Fibre Lasers
Pedersen, Martin Erland Vestergaard
and numerically. For the intermodal four-wave mixing experiment an alternative version of the Generalised Non-Linear Schrödinger Equation is derived, which includes the correct dispersion of the transverse field. It is observed that the alternative version of the Generalised Non-Linear Schrödinger Equation......, as opposed to the commonly used version, is able to reproduce the intermodal four-wave mixing experiment. The relation between the intramodal self-phase modulation and the intramodal Raman effect is determined from experimental measurements on a number of step-index fibres. The Raman fraction is found...
Crosswell Imaging Technology & Advanced DSR Navigation for Horizontal Directional Drilling
Larry Stolarczyk
2008-08-08
The objective of Phase II is to develop and demonstrate real-time measurement-while-drilling (MWD) for guidance and navigation of drill strings during horizontal drilling operations applicable to both short and long holes. The end product of Phase II is a functional drill-string assembly outfitted with a commercial version of Drill String Radar (DSR). Project Objectives Develop and demonstrate a dual-phase methodology of in-seam drilling, imaging, and structure confirmation. This methodology, illustrated in Figure 1, includes: (1) Using RIM to image between drill holes for seam thickness estimates and in-seam structures detection. Completed, February 2005; and (2) Using DSR for real-time MWD guidance and navigation of drillstrings during horizontal drilling operations. Completed, November 2008. As of November 2008, the Phase II portion of Contract DE-FC26-04NT42085 is about 99% complete, including milestones and tasks original outlined as Phase II work. The one percent deficiency results from MSHA-related approvals which have yet to be granted (at the time of reporting). These approvals are pending and are do not negatively impact the scope of work or project objectives.
Linearly constrained minimax optimization
Madsen, Kaj; Schjær-Jacobsen, Hans
1978-01-01
We present an algorithm for nonlinear minimax optimization subject to linear equality and inequality constraints which requires first order partial derivatives. The algorithm is based on successive linear approximations to the functions defining the problem. The resulting linear subproblems...
SIGMA1-2007, Doppler Broadening ENDF Format Linear-Linear. Interpolated Point Cross Section
2007-01-01
1 - Description of problem or function: SIGMA-1 Doppler broadens evaluated Cross sections given in the linear-linear interpolation form of the ENDF/B Format to one final temperature. The data is Doppler broadened, thinned, and output in the ENDF/B Format. IAEA0854/15: This version include the updates up to January 30, 2007. Changes in ENDF/B-VII Format and procedures, as well as the evaluations themselves, make it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2007 (2007 Version) to accurately process current ENDF/B-VII evaluations. The present code can handle all existing ENDF/B-VI evaluations through release 8, which will be the last release of ENDF/B-VI. 2 - Modifications from previous versions: Sigma-1 VERS. 2007-1 (Jan. 2007): checked against all ENDF/B-VII; increased page size from 60,000 to 360,000 energy points 3 - Method of solution: The energy grid is selected to ensure that the broadened data is linear-linear interpolable. SIGMA-1 starts from the free-atom Doppler broadening equations and adds the assumptions of linear data within the table and constant data outside the range of the table. If the Original data is not at zero Kelvin, the data is broadened by the effective temperature difference to the final temperature. If the data is already at a temperature higher than the final temperature, Doppler broadening is not performed. 4 - Restrictions on the complexity of the problem: The input to SIGMA-1 must be data which vary linearly in energy and cross section between tabulated points. The LINEAR program provides such data. LINEAR uses only the ENDF/B BCD Format tape and copies all sections except File 3 as read. Since File 3 data are in identical Format for ENDF/B Versions I through VI, the program can be used with all these versions. - The present version Doppler broadens only to one final temperature
SLS Model Based Design: A Navigation Perspective
Oliver, T. Emerson; Anzalone, Evan; Park, Thomas; Geohagan, Kevin
2018-01-01
The SLS Program has implemented a Model-based Design (MBD) and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team is responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1B design, the additional GPS Receiver hardware model is managed as a DMM at the vehicle design level. This paper describes the models, and discusses the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the navigation components.
Foundations of linear and generalized linear models
Agresti, Alan
2015-01-01
A valuable overview of the most important ideas and results in statistical analysis Written by a highly-experienced author, Foundations of Linear and Generalized Linear Models is a clear and comprehensive guide to the key concepts and results of linear statistical models. The book presents a broad, in-depth overview of the most commonly used statistical models by discussing the theory underlying the models, R software applications, and examples with crafted models to elucidate key ideas and promote practical model building. The book begins by illustrating the fundamentals of linear models,
Navigating nuclear science: Enhancing analysis through visualization
Irwin, N.H.; Berkel, J. van; Johnson, D.K.; Wylie, B.N.
1997-09-01
Data visualization is an emerging technology with high potential for addressing the information overload problem. This project extends the data visualization work of the Navigating Science project by coupling it with more traditional information retrieval methods. A citation-derived landscape was augmented with documents using a text-based similarity measure to show viability of extension into datasets where citation lists do not exist. Landscapes, showing hills where clusters of similar documents occur, can be navigated, manipulated and queried in this environment. The capabilities of this tool provide users with an intuitive explore-by-navigation method not currently available in today`s retrieval systems.
Completeness Results for Linear Logic on Petri Nets
Engberg, Uffe Henrik; Winskel, Glynn
1993-01-01
Completeness is shown for several versions of Girard's linear logic with respect to Petri nets as the class of models. The strongest logic considered is intuitionistic linear logic, with $otimes$, $-!circ$, &, $oplus$ and the exponential ! (''of course´´), and forms of quantification. This logic ...
Venous catheterization with ultrasound navigation
Kasatkin, A. A.; Nigmatullina, A. R.; Urakov, A. L.
2015-01-01
By ultrasound scanning it was determined that respiratory movements made by chest of healthy and sick person are accompanied by respiratory chest rise of internal jugular veins. During the exhalation of an individual diameter of his veins increases and during the breath it decreases down to the complete disappearing if their lumen. Change of the diameter of internal jugular veins in different phases can influence significantly the results of vein puncture and cauterization in patients. The purpose of this research is development of the method increasing the efficiency and safety of cannulation of internal jugular veins by the ultrasound visualization. We suggested the method of catheterization of internal jugular veins by the ultrasound navigation during the execution of which the puncture of venous wall by puncture needle and the following conduction of J-guide is carried out at the moment of patient’s exhalation. This method decreases the risk of complications development during catheterization of internal jugular vein due to exclusion of perforating wound of vein and subjacent tissues and anatomical structures
Venous catheterization with ultrasound navigation
Kasatkin, A. A., E-mail: ant-kasatkin@yandex.ru; Nigmatullina, A. R. [Izhevsk State Medical Academy, Kommunarov street, 281, Izhevsk, Russia, 426034 (Russian Federation); Urakov, A. L., E-mail: ant-kasatkin@yandex.ru [Institute of Mechanics Ural Branch of Russian Academy of Sciences, T.Baramzinoy street 34, Izhevsk, Russia, 426067, Izhevsk (Russian Federation); Izhevsk State Medical Academy, Kommunarov street, 281, Izhevsk, Russia, 426034 (Russian Federation)
2015-11-17
By ultrasound scanning it was determined that respiratory movements made by chest of healthy and sick person are accompanied by respiratory chest rise of internal jugular veins. During the exhalation of an individual diameter of his veins increases and during the breath it decreases down to the complete disappearing if their lumen. Change of the diameter of internal jugular veins in different phases can influence significantly the results of vein puncture and cauterization in patients. The purpose of this research is development of the method increasing the efficiency and safety of cannulation of internal jugular veins by the ultrasound visualization. We suggested the method of catheterization of internal jugular veins by the ultrasound navigation during the execution of which the puncture of venous wall by puncture needle and the following conduction of J-guide is carried out at the moment of patient’s exhalation. This method decreases the risk of complications development during catheterization of internal jugular vein due to exclusion of perforating wound of vein and subjacent tissues and anatomical structures.
Qatari Women Navigating Gendered Space
Krystyna Golkowska
2017-10-01
Full Text Available ADespite growing interest in the lived experience of Muslim women in Arab countries, there is still a dearth of studies on the Gulf region. This article focuses on Qatar, a Gulf Corporation Council (GCC country, to explore its changing sociocultural landscape and reflect on Qatari women’s agency within the framework of the traditional gendered space model. Applying Grounded Theory methodology to data collected from a variety of scholarly and non-scholarly sources, the author offers a themed overview of factors that facilitate and constrain Qatari women’s mobility. The findings testify to a significant increase in female presence and visibility in the public sphere—specifically in the spaces of education, employment, and sports. They also show that young Qatari women exercise agency through navigating the existing systems rather than question traditional socio-cultural norms. The paper identifies this search for a middle ground between tradition and modernity and its ideological underpinnings as the area of future research that should be led by Qatari women themselves.
Le texte suivant remplace la version française de l'encadré paru en page 2 du Bulletin 28/2003 : Le 1er juillet 1953, les représentants des douze Etats Membres fondateurs du CERN signèrent la convention de l'Organisation. Aujourd'hui, le CERN compte vingt Etats Membres Européens : l'Allemagne, l'Autriche, la Belgique, la Bulgarie, le Danemark, l'Espagne, la Finlande, la France, la Grèce, la Hongrie, l'Italie, la Norvège, les Pays-Bas, la Pologne, le Portugal, la République Slovaque, la République Tchèque, le Royaume-Uni, la Suède, et la Suisse. Les Etats-Unis, l'Inde, l'Israël, le Japon, la Fédération Russe, la Turquie, la Commission Européenne et l'UNESCO ont un statut d'Etat observateur.
Svetlana Pavlova
2014-12-01
Full Text Available European Air Traffic Management system requires continuous improvements as air traffic is increasingday by day. For this purpose it was developed by international organizations Free Route Airspace and PerformanceBased Navigation concepts that allow to offer a required level of safety, capacity, environmental performance alongwith cost-effectiveness. The aim of the article is to provide detailed analysis of Free Route Airspace and PerformanceBased Navigation implementation status within European region including Ukrainian air navigation system.
Yong-Jin Yoon; King Ho Holden Li; Jiahe Steven Lee; Woo-Tae Park
2015-01-01
Global Positioning System and Inertial Navigation System can be used to determine position and velocity. A Global Positioning System module is able to accurately determine position without sensor drift, but its usage is limited in heavily urbanized environments and heavy vegetation. While high-cost tactical-grade Inertial Navigation System can determine position accurately, low-cost micro-electro-mechanical system Inertial Navigation System sensors are plagued by significant errors. Global Po...
Smart parking management and navigation system
Saadeldin, Mohamed
2017-01-01
Various examples are provided for smart parking management, which can include navigation. In one example, a system includes a base station controller configured to: receive a wireless signal from a parking controller located at a parking space
Challenges in navigational strategies for flexible endoscopy
van der Stap, N.; van der Heijden, Ferdinand; Broeders, Ivo Adriaan Maria Johannes
Automating flexible endoscope navigation could lead to an increase in patient safety for endoluminal therapeutic procedures. Additionally, it may decrease the costs of diagnostic flexible endoscope procedures by shortening the learning curve and increasing the efficiency of insertion. Earlier
Fuzzy Logic Controller for Small Satellites Navigation
Della Pietra, G; Falzini, S; Colzi, E; Crisconio, M
2005-01-01
.... The navigator aims at operating satellites in orbit with a minimum ground support and very good performances, by the adoption of innovative technologies, such as attitude observation GPS, attitude...
From Navigation to Star Hopping: Forgotten Formulae
IAS Admin
Mathematics and wrote a book Navigation and Nautical Astronomy for Sea-men in 1821 with tables ... and arcseconds. The reference ... Roger W Sinnott, an astronomy graduate from Harvard, served on the editorial board of the monthly ...
78 FR 68077 - Navigation Safety Advisory Council
2013-11-13
... Privacy Act notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73... commence in calendar year 2014. (4) Navigation Rules Regulatory Project. The Council will receive an update...
Navigation with a passive brain based interface
Erp, J.B.F. van; Werkhoven, P.J.; Thurlings, M.E.; Brouwer, A.-M.
2009-01-01
In this paper, we describe a Brain Computer Interface (BCI) for navigation. The system is based on detecting brain signals that are elicited by tactile stimulation on the torso indicating the desired direction.
Mars rover local navigation and hazard avoidance
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.
Onboard Optical Navigation Measurement Processing in GEONS
National Aeronautics and Space Administration — Optical Navigation (OpNav) measurements derived from spacecraft-based images are a powerful data type in the precision orbit determination process. OpNav...
NOAA Seamless Raster Navigational Charts (RNC)
National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Seamless Raster Chart Server provides a seamless collarless mosaic of the NOAA Raster Navigational Charts (RNC). The RNC are a collection of approximately...
Neurobiologically inspired mobile robot navigation and planning
Mathias Quoy
2007-11-01
Full Text Available After a short review of biologically inspired navigation architectures, mainly relying on modeling the hippocampal anatomy, or at least some of its functions, we present a navigation and planning model for mobile robots. This architecture is based on a model of the hippocampal and prefrontal interactions. In particular, the system relies on the definition of a new cell type “transition cells” that encompasses traditional “place cells”.
Unraveling navigational strategies in migratory insects
Merlin, Christine; Heinze, Stanley; Reppert, Steven M.
2011-01-01
Long-distance migration is a strategy some animals use to survive a seasonally changing environment. To reach favorable grounds, migratory animals have evolved sophisticated navigational mechanisms that rely on a map and compasses. In migratory insects, the existence of a map sense (sense of position) remains poorly understood, but recent work has provided new insights into the mechanisms some compasses use for maintaining a constant bearing during long-distance navigation. The best-studied d...
Magnetic navigation and tracking of underwater vehicles
Teixeira, F.C.; Pascoal, A.M.
for the navigation of AUVs has been proposed many years ago but the concept still requires practical demonstration. Implementation issues One of the advantages of mag- netic navigation consists in being passive and economical in terms of energy. Magnetic sensors do... like the present one, that require magnetic measurements with very high precision. A typical solution to this problem consists in the placement of magnetic sensors as far away as possible from the sources of noise but this may not be practical...
Navigational Strategies of Migrating Monarch Butterflies
2014-11-10
AFRL-OSR-VA-TR-2014-0339 NAVIGATIONAL STRATEGIES OF MIGRATING MONARCH BUTTERFLIES Steven Reppert UNIVERSITY OF MASSACHUSETTS Final Report 11/10/2014...Final Progress Statement to (Dr. Patrick Bradshaw) Contract/Grant Title: Navigational Strategies of Migrating Monarch Butterflies Contract...Grant #: FA9550-10-1-0480 Reporting Period: 01-Sept-10 to 31-Aug-14 Overview of accomplishments: Migrating monarch butterflies (Danaus
Clinical applications of virtual navigation bronchial intervention.
Kajiwara, Naohiro; Maehara, Sachio; Maeda, Junichi; Hagiwara, Masaru; Okano, Tetsuya; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko
2018-01-01
In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors. We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases. Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely. Preoperative simulation using virtual navigation bronchial intervention reduces the surgeon's stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments
Shape Perception and Navigation in Blind Adults
Gori, Monica; Cappagli, Giulia; Baud-Bovy, Gabriel; Finocchietti, Sara
2017-01-01
Different sensory systems interact to generate a representation of space and to navigate. Vision plays a critical role in the representation of space development. During navigation, vision is integrated with auditory and mobility cues. In blind individuals, visual experience is not available and navigation therefore lacks this important sensory signal. In blind individuals, compensatory mechanisms can be adopted to improve spatial and navigation skills. On the other hand, the limitations of these compensatory mechanisms are not completely clear. Both enhanced and impaired reliance on auditory cues in blind individuals have been reported. Here, we develop a new paradigm to test both auditory perception and navigation skills in blind and sighted individuals and to investigate the effect that visual experience has on the ability to reproduce simple and complex paths. During the navigation task, early blind, late blind and sighted individuals were required first to listen to an audio shape and then to recognize and reproduce it by walking. After each audio shape was presented, a static sound was played and the participants were asked to reach it. Movements were recorded with a motion tracking system. Our results show three main impairments specific to early blind individuals. The first is the tendency to compress the shapes reproduced during navigation. The second is the difficulty to recognize complex audio stimuli, and finally, the third is the difficulty in reproducing the desired shape: early blind participants occasionally reported perceiving a square but they actually reproduced a circle during the navigation task. We discuss these results in terms of compromised spatial reference frames due to lack of visual input during the early period of development. PMID:28144226
Davis, Bradley M
2007-01-01
.... Results from both experiments indicate that augmented visual displays reduced time to complete navigation, maintained situation awareness, and drastically reduced mental workload in comparison...
Orthogonal sparse linear discriminant analysis
Liu, Zhonghua; Liu, Gang; Pu, Jiexin; Wang, Xiaohong; Wang, Haijun
2018-03-01
Linear discriminant analysis (LDA) is a linear feature extraction approach, and it has received much attention. On the basis of LDA, researchers have done a lot of research work on it, and many variant versions of LDA were proposed. However, the inherent problem of LDA cannot be solved very well by the variant methods. The major disadvantages of the classical LDA are as follows. First, it is sensitive to outliers and noises. Second, only the global discriminant structure is preserved, while the local discriminant information is ignored. In this paper, we present a new orthogonal sparse linear discriminant analysis (OSLDA) algorithm. The k nearest neighbour graph is first constructed to preserve the locality discriminant information of sample points. Then, L2,1-norm constraint on the projection matrix is used to act as loss function, which can make the proposed method robust to outliers in data points. Extensive experiments have been performed on several standard public image databases, and the experiment results demonstrate the performance of the proposed OSLDA algorithm.
NFC Internal: An Indoor Navigation System
Ozdenizci, Busra; Coskun, Vedat; Ok, Kerem
2015-01-01
Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability. PMID:25825976
NFC Internal: An Indoor Navigation System
Busra Ozdenizci
2015-03-01
Full Text Available Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability.
A new systematic calibration method of ring laser gyroscope inertial navigation system
Wei, Guo; Gao, Chunfeng; Wang, Qi; Wang, Qun; Xiong, Zhenyu; Long, Xingwu
2016-10-01
Inertial navigation system has been the core component of both military and civil navigation systems. Before the INS is put into application, it is supposed to be calibrated in the laboratory in order to compensate repeatability error caused by manufacturing. Discrete calibration method cannot fulfill requirements of high-accurate calibration of the mechanically dithered ring laser gyroscope navigation system with shock absorbers. This paper has analyzed theories of error inspiration and separation in detail and presented a new systematic calibration method for ring laser gyroscope inertial navigation system. Error models and equations of calibrated Inertial Measurement Unit are given. Then proper rotation arrangement orders are depicted in order to establish the linear relationships between the change of velocity errors and calibrated parameter errors. Experiments have been set up to compare the systematic errors calculated by filtering calibration result with those obtained by discrete calibration result. The largest position error and velocity error of filtering calibration result are only 0.18 miles and 0.26m/s compared with 2 miles and 1.46m/s of discrete calibration result. These results have validated the new systematic calibration method and proved its importance for optimal design and accuracy improvement of calibration of mechanically dithered ring laser gyroscope inertial navigation system.
Daugherty, Ana M; Yuan, Peng; Dahle, Cheryl L; Bender, Andrew R; Yang, Yiqin; Raz, Naftali
2015-09-01
Studies of human navigation in virtual maze environments have consistently linked advanced age with greater distance traveled between the start and the goal and longer duration of the search. Observations of search path geometry suggest that routes taken by older adults may be unnecessarily complex and that excessive path complexity may be an indicator of cognitive difficulties experienced by older navigators. In a sample of healthy adults, we quantify search path complexity in a virtual Morris water maze with a novel method based on fractal dimensionality. In a two-level hierarchical linear model, we estimated improvement in navigation performance across trials by a decline in route length, shortening of search time, and reduction in fractal dimensionality of the path. While replicating commonly reported age and sex differences in time and distance indices, a reduction in fractal dimension of the path accounted for improvement across trials, independent of age or sex. The volumes of brain regions associated with the establishment of cognitive maps (parahippocampal gyrus and hippocampus) were related to path dimensionality, but not to the total distance and time. Thus, fractal dimensionality of a navigational path may present a useful complementary method of quantifying performance in navigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Wireless Cortical Brain-Machine Interface for Whole-Body Navigation in Primates
Rajangam, Sankaranarayani; Tseng, Po-He; Yin, Allen; Lehew, Gary; Schwarz, David; Lebedev, Mikhail A.; Nicolelis, Miguel A. L.
2016-03-01
Several groups have developed brain-machine-interfaces (BMIs) that allow primates to use cortical activity to control artificial limbs. Yet, it remains unknown whether cortical ensembles could represent the kinematics of whole-body navigation and be used to operate a BMI that moves a wheelchair continuously in space. Here we show that rhesus monkeys can learn to navigate a robotic wheelchair, using their cortical activity as the main control signal. Two monkeys were chronically implanted with multichannel microelectrode arrays that allowed wireless recordings from ensembles of premotor and sensorimotor cortical neurons. Initially, while monkeys remained seated in the robotic wheelchair, passive navigation was employed to train a linear decoder to extract 2D wheelchair kinematics from cortical activity. Next, monkeys employed the wireless BMI to translate their cortical activity into the robotic wheelchair’s translational and rotational velocities. Over time, monkeys improved their ability to navigate the wheelchair toward the location of a grape reward. The navigation was enacted by populations of cortical neurons tuned to whole-body displacement. During practice with the apparatus, we also noticed the presence of a cortical representation of the distance to reward location. These results demonstrate that intracranial BMIs could restore whole-body mobility to severely paralyzed patients in the future.
Extensions of MAD Version 8 to Include Beam Acceleration
Raubenheimer, Tor O
2000-01-01
In this paper, the authors describe modifications to MAD version 8.23 to include linear accelerator cavities and beam acceleration. An additional energy variable has been added which is modified as the beam passes through LCAV elements (linear accelerator cavities) and can be used as a constraint in matching commands. The calculation of the beta functions and phase advance is consistent with that in other codes that treat acceleration such as TRANSPORT or DIMAD. These modifications allow this version of MAD to be used for the design and modeling of linacs and the authors present examples from the Next Linear Collider design as well as a muon acceleration complex. The code is available from CERN or SLAC
Macroscopic and non-linear quantum games
Aerts, D.; D'Hooghe, A.; Posiewnik, A.; Pykacz, J.
2005-01-01
Full text: We consider two models of quantum games. The first one is Marinatto and Weber's 'restricted' quantum game in which only the identity and the spin-flip operators are used. We show that this quantum game allows macroscopic mechanistic realization with the use of a version of the 'macroscopic quantum machine' described by Aerts already in 1980s. In the second model we use non-linear quantum state transformations which operate on points of spin-1/2 on the Bloch sphere and which can be used to distinguish optimally between two non-orthogonal states. We show that efficiency of these non-linear strategies out-perform any linear ones. Some hints on the possible theory of non-linear quantum games are given. (author)
Fuzzy Behavior Modulation with Threshold Activation for Autonomous Vehicle Navigation
Tunstel, Edward
2000-01-01
This paper describes fuzzy logic techniques used in a hierarchical behavior-based architecture for robot navigation. An architectural feature for threshold activation of fuzzy-behaviors is emphasized, which is potentially useful for tuning navigation performance in real world applications. The target application is autonomous local navigation of a small planetary rover. Threshold activation of low-level navigation behaviors is the primary focus. A preliminary assessment of its impact on local navigation performance is provided based on computer simulations.
E-navigation Services for Non-SOLAS Ships
Kwang An
2016-06-01
Full Text Available It is clearly understood that the main benefits of e-navigation are improved safety and better protection of the environment through the promotion of standards of navigational system and a reduction in human error. In order to meet the expectations on the benefit of e-navigation, e-navigation services should be more focused on non-SOLAS ships. The purpose of this paper is to present necessary e-navigation services for non-SOLAS ships in order to prevent marine accidents in Korean coastal waters. To meet the objectives of the study, an examination on the present navigation and communication system for non-SOLAS ships was performed. Based on the IMO's e-navigation Strategy Implementation Plan (SIP and Korea's national SIP for e-navigation, future trends for the development and implementation of e-navigation were discussed. Consequently, Electronic Navigational Chart (ENC download and ENC up-date service, ENC streaming service, route support service and communication support service based on Maritime Cloud were presented as essential e-navigation services for non-SOLAS ships. This study will help for the planning and designing of the Korean e-navigation system. It is expected that the further researches on the navigation support systems based on e-navigation will be carried out in order to implement the essential e-navigation services for non-SOLAS ships.
Architectural elements of hybrid navigation systems for future space transportation
Trigo, Guilherme F.; Theil, Stephan
2017-12-01
The fundamental limitations of inertial navigation, currently employed by most launchers, have raised interest for GNSS-aided solutions. Combination of inertial measurements and GNSS outputs allows inertial calibration online, solving the issue of inertial drift. However, many challenges and design options unfold. In this work we analyse several architectural elements and design aspects of a hybrid GNSS/INS navigation system conceived for space transportation. The most fundamental architectural features such as coupling depth, modularity between filter and inertial propagation, and open-/closed-loop nature of the configuration, are discussed in the light of the envisaged application. Importance of the inertial propagation algorithm and sensor class in the overall system are investigated, being the handling of sensor errors and uncertainties that arise with lower grade sensory also considered. In terms of GNSS outputs we consider receiver solutions (position and velocity) and raw measurements (pseudorange, pseudorange-rate and time-difference carrier phase). Receiver clock error handling options and atmospheric error correction schemes for these measurements are analysed under flight conditions. System performance with different GNSS measurements is estimated through covariance analysis, being the differences between loose and tight coupling emphasized through partial outage simulation. Finally, we discuss options for filter algorithm robustness against non-linearities and system/measurement errors. A possible scheme for fault detection, isolation and recovery is also proposed.
Spatial filtering velocimeter for vehicle navigation with extended measurement range
He, Xin; Zhou, Jian; Nie, Xiaoming; Long, Xingwu
2015-05-01
The idea of using spatial filtering velocimeter is proposed to provide accurate velocity information for vehicle autonomous navigation system. The presented spatial filtering velocimeter is based on a CMOS linear image sensor. The limited frame rate restricts high speed measurement of the vehicle. To extend measurement range of the velocimeter, a method of frequency shifting is put forward. Theoretical analysis shows that the frequency of output signal can be reduced and the measurement range can be doubled by this method when the shifting direction is set the same with that of image velocity. The approach of fast Fourier transform (FFT) is employed to obtain the power spectra of the spatially filtered signals. Because of limited frequency resolution of FFT, a frequency spectrum correction algorithm, called energy centrobaric correction, is used to improve the frequency resolution. The correction accuracy energy centrobaric correction is analyzed. Experiments are carried out to measure the moving surface of a conveyor belt. The experimental results show that the maximum measurable velocity is about 800deg/s without frequency shifting, 1600deg/s with frequency shifting, when the frame rate of the image is about 8117 Hz. Therefore, the measurement range is doubled by the method of frequency shifting. Furthermore, experiments were carried out to measure the vehicle velocity simultaneously using both the designed SFV and a laser Doppler velocimeter (LDV). The measurement results of the presented SFV are coincident with that of the LDV, but with bigger fluctuation. Therefore, it has the potential of application to vehicular autonomous navigation.
Autonomous Navigation with Constrained Consistency for C-Ranger
Shujing Zhang
2014-06-01
Full Text Available Autonomous underwater vehicles (AUVs have become the most widely used tools for undertaking complex exploration tasks in marine environments. Their synthetic ability to carry out localization autonomously and build an environmental map concurrently, in other words, simultaneous localization and mapping (SLAM, are considered to be pivotal requirements for AUVs to have truly autonomous navigation. However, the consistency problem of the SLAM system has been greatly ignored during the past decades. In this paper, a consistency constrained extended Kalman filter (EKF SLAM algorithm, applying the idea of local consistency, is proposed and applied to the autonomous navigation of the C-Ranger AUV, which is developed as our experimental platform. The concept of local consistency (LC is introduced after an explicit theoretical derivation of the EKF-SLAM system. Then, we present a locally consistency-constrained EKF-SLAM design, LC-EKF, in which the landmark estimates used for linearization are fixed at the beginning of each local time period, rather than evaluated at the latest landmark estimates. Finally, our proposed LC-EKF algorithm is experimentally verified, both in simulations and sea trials. The experimental results show that the LC-EKF performs well with regard to consistency, accuracy and computational efficiency.
Context-Aided Sensor Fusion for Enhanced Urban Navigation
Enrique David Martí
2012-12-01
Full Text Available The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments.
Context-Aided Sensor Fusion for Enhanced Urban Navigation
Martí, Enrique David; Martín, David; García, Jesús; de la Escalera, Arturo; Molina, José Manuel; Armingol, José María
2012-01-01
The deployment of Intelligent Vehicles in urban environments requires reliable estimation of positioning for urban navigation. The inherent complexity of this kind of environments fosters the development of novel systems which should provide reliable and precise solutions to the vehicle. This article details an advanced GNSS/IMU fusion system based on a context-aided Unscented Kalman filter for navigation in urban conditions. The constrained non-linear filter is here conditioned by a contextual knowledge module which reasons about sensor quality and driving context in order to adapt it to the situation, while at the same time it carries out a continuous estimation and correction of INS drift errors. An exhaustive analysis has been carried out with available data in order to characterize the behavior of available sensors and take it into account in the developed solution. The performance is then analyzed with an extensive dataset containing representative situations. The proposed solution suits the use of fusion algorithms for deploying Intelligent Transport Systems in urban environments. PMID:23223080
Architectural elements of hybrid navigation systems for future space transportation
Trigo, Guilherme F.; Theil, Stephan
2018-06-01
The fundamental limitations of inertial navigation, currently employed by most launchers, have raised interest for GNSS-aided solutions. Combination of inertial measurements and GNSS outputs allows inertial calibration online, solving the issue of inertial drift. However, many challenges and design options unfold. In this work we analyse several architectural elements and design aspects of a hybrid GNSS/INS navigation system conceived for space transportation. The most fundamental architectural features such as coupling depth, modularity between filter and inertial propagation, and open-/closed-loop nature of the configuration, are discussed in the light of the envisaged application. Importance of the inertial propagation algorithm and sensor class in the overall system are investigated, being the handling of sensor errors and uncertainties that arise with lower grade sensory also considered. In terms of GNSS outputs we consider receiver solutions (position and velocity) and raw measurements (pseudorange, pseudorange-rate and time-difference carrier phase). Receiver clock error handling options and atmospheric error correction schemes for these measurements are analysed under flight conditions. System performance with different GNSS measurements is estimated through covariance analysis, being the differences between loose and tight coupling emphasized through partial outage simulation. Finally, we discuss options for filter algorithm robustness against non-linearities and system/measurement errors. A possible scheme for fault detection, isolation and recovery is also proposed.
2013-07-10
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 105 [Docket No. USCG-2013-0397] RIN 1625-AC06 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments; Correction AGENCY: Coast Guard, DHS. ACTION: Final rule; correction. SUMMARY: The Coast Guard published a final rule...
2010-08-11
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Parts 3 and 165 [Docket No. USCG-2010-0351] RIN 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River, WA AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: This rule makes non-substantive...
Steffes, S.; Dumke, M.; Heise, D.; Sagliano, M.; Samaan, M.; Theil, S.; Boslooper, E.C.; Oosterling, J.A.J.; Schulte, J.; Skaborn, D.; Söderholm, S.; Conticello, S.; Esposito, M.; Yanson, Y.; Monna, B.; Stelwagen, F.; Visee, R.
2014-01-01
The goal of the SINPLEX project is to develop an innovative solution to significantly reduce the mass of the navigation subsystem for exploration missions which include landing and/or rendezvous and capture phases. The system mass is reduced while still maintaining good navigation performance as
Integrated navigation method of a marine strapdown inertial navigation system using a star sensor
Wang, Qiuying; Diao, Ming; Gao, Wei; Zhu, Minghong; Xiao, Shu
2015-01-01
This paper presents an integrated navigation method of the strapdown inertial navigation system (SINS) using a star sensor. According to the principle of SINS, its own navigation information contains an error that increases with time. Hence, the inertial attitude matrix from the star sensor is introduced as the reference information to correct the SINS increases error. For the integrated navigation method, the vehicle’s attitude can be obtained in two ways: one is calculated from SINS; the other, which we have called star sensor attitude, is obtained as the product between the SINS position and the inertial attitude matrix from the star sensor. Therefore, the SINS position error is introduced in the star sensor attitude error. Based on the characteristics of star sensor attitude error and the mathematical derivation, the SINS navigation errors can be obtained by the coupling calculation between the SINS attitude and the star sensor attitude. Unlike several current techniques, the navigation process of this method is non-radiating and invulnerable to jamming. The effectiveness of this approach was demonstrated by simulation and experimental study. The results show that this integrated navigation method can estimate the attitude error and the position error of SINS. Therefore, the SINS navigation accuracy is improved. (paper)
2010-08-18
... 3 and 165 to reflect changes in Coast Guard internal organizational structure. Sector Portland and... 1625-ZA25 Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Sector... Waters; Technical, Organizational, and Conforming Amendments, Sector Columbia River.'' 2. On page 48564...
Shores, David; Goza, Sharon P.; McKeegan, Cheyenne; Easley, Rick; Way, Janet; Everett, Shonn; Guerra, Mark; Kraesig, Ray; Leu, William
2013-01-01
Enigma Version 12 software combines model building, animation, and engineering visualization into one concise software package. Enigma employs a versatile user interface to allow average users access to even the most complex pieces of the application. Using Enigma eliminates the need to buy and learn several software packages to create an engineering visualization. Models can be created and/or modified within Enigma down to the polygon level. Textures and materials can be applied for additional realism. Within Enigma, these models can be combined to create systems of models that have a hierarchical relationship to one another, such as a robotic arm. Then these systems can be animated within the program or controlled by an external application programming interface (API). In addition, Enigma provides the ability to use plug-ins. Plugins allow the user to create custom code for a specific application and access the Enigma model and system data, but still use the Enigma drawing functionality. CAD files can be imported into Enigma and combined to create systems of computer graphics models that can be manipulated with constraints. An API is available so that an engineer can write a simulation and drive the computer graphics models with no knowledge of computer graphics. An animation editor allows an engineer to set up sequences of animations generated by simulations or by conceptual trajectories in order to record these to highquality media for presentation. Enigma Version 12 Lyndon B. Johnson Space Center, Houston, Texas 28 NASA Tech Briefs, September 2013 Planetary Protection Bioburden Analysis Program NASA's Jet Propulsion Laboratory, Pasadena, California This program is a Microsoft Access program that performed statistical analysis of the colony counts from assays performed on the Mars Science Laboratory (MSL) spacecraft to determine the bioburden density, 3-sigma biodensity, and the total bioburdens required for the MSL prelaunch reports. It also contains numerous
Tuey, R. C.
1972-01-01
Computer solutions of linear programming problems are outlined. Information covers vector spaces, convex sets, and matrix algebra elements for solving simultaneous linear equations. Dual problems, reduced cost analysis, ranges, and error analysis are illustrated.
Peterson, David; Stofleth, Jerome H.; Saul, Venner W.
2017-07-11
Linear shaped charges are described herein. In a general embodiment, the linear shaped charge has an explosive with an elongated arrowhead-shaped profile. The linear shaped charge also has and an elongated v-shaped liner that is inset into a recess of the explosive. Another linear shaped charge includes an explosive that is shaped as a star-shaped prism. Liners are inset into crevices of the explosive, where the explosive acts as a tamper.
Classifying Linear Canonical Relations
Lorand, Jonathan
2015-01-01
In this Master's thesis, we consider the problem of classifying, up to conjugation by linear symplectomorphisms, linear canonical relations (lagrangian correspondences) from a finite-dimensional symplectic vector space to itself. We give an elementary introduction to the theory of linear canonical relations and present partial results toward the classification problem. This exposition should be accessible to undergraduate students with a basic familiarity with linear algebra.
Comparison between clinical grading and navigation data of knee laxity in ACL-deficient knees
Yamamoto Yuji
2010-11-01
Full Text Available Abstract Background The latest version of the navigation system for anterior cruciate ligament (ACL reconstruction has the supplementary ability to assess knee stability before and after ACL reconstruction. In this study, we compared navigation data between clinical grades in ACL-deficient knees and also analyzed correlation between clinical grading and navigation data. Methods 150 ACL deficient knees that received primary ACL reconstruction using an image-free navigation system were included. For clinical evaluation, the Lachman, anterior drawer, and pivot shift tests were performed under general anesthesia and were graded by an examiner. For the assessment of knee stability using the navigation system, manual tests were performed again before ACL reconstruction. Navigation data were recorded as anteroposterior (AP displacement of the tibia for the Lachman and anterior drawer tests, and both AP displacement and tibial rotation for the pivot shift test. Results Navigation data of each clinical grade were as follows; Lachman test grade 1+: 10.0 mm, grade 2+: 13.2 ± 3.1 mm, grade 3+: 14.5 ± 3.3 mm, anterior drawer test grade 1+: 6.8 ± 1.4 mm, grade 2+: 7.4 ± 1.8 mm, grade 3+: 9.1 ± 2.3 mm, pivot shift test grade 1+: 3.9 ± 1.8 mm/21.5° ± 7.8°, grade 2+: 4.8 ± 2.1 mm/21.8° ± 7.1°, and grade 3+: 6.0 ± 3.2 mm/21.1° ± 7.1°. There were positive correlations between clinical grading and AP displacement in the Lachman, and anterior drawer tests. Although positive correlations between clinical grading and AP displacement in pivot shift test were found, there were no correlations between clinical grading and tibial rotation in pivot shift test. Conclusions In response to AP force, the navigation system can provide the surgeon with correct objective data for knee laxity in ACL deficient knees. During the pivot shift test, physicians may grade according to the displacement of the tibia, rather than rotation.
Intelligent navigation to improve obstetrical sonography.
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
Navigation Architecture for a Space Mobile Network
Valdez, Jennifer E.; Ashman, Benjamin; Gramling, Cheryl; Heckler, Gregory W.; Carpenter, Russell
2016-01-01
The Tracking and Data Relay Satellite System (TDRSS) Augmentation Service for Satellites (TASS) is a proposed beacon service to provide a global, space based GPS augmentation service based on the NASA Global Differential GPS (GDGPS) System. The TASS signal will be tied to the GPS time system and usable as an additional ranging and Doppler radiometric source. Additionally, it will provide data vital to autonomous navigation in the near Earth regime, including space weather information, TDRS ephemerides, Earth Orientation Parameters (EOP), and forward commanding capability. TASS benefits include enhancing situational awareness, enabling increased autonomy, and providing near real-time command access for user platforms. As NASA Headquarters' Space Communication and Navigation Office (SCaN) begins to move away from a centralized network architecture and towards a Space Mobile Network (SMN) that allows for user initiated services, autonomous navigation will be a key part of such a system. This paper explores how a TASS beacon service enables the Space Mobile Networking paradigm, what a typical user platform would require, and provides an in-depth analysis of several navigation scenarios and operations concepts. This paper provides an overview of the TASS beacon and its role within the SMN and user community. Supporting navigation analysis is presented for two user mission scenarios: an Earth observing spacecraft in low earth orbit (LEO), and a highly elliptical spacecraft in a lunar resonance orbit. These diverse flight scenarios indicate the breadth of applicability of the TASS beacon for upcoming users within the current network architecture and in the SMN.
Adaptation to Variance of Stimuli in Drosophila Larva Navigation
Wolk, Jason; Gepner, Ruben; Gershow, Marc
In order to respond to stimuli that vary over orders of magnitude while also being capable of sensing very small changes, neural systems must be capable of rapidly adapting to the variance of stimuli. We study this adaptation in Drosophila larvae responding to varying visual signals and optogenetically induced fictitious odors using an infrared illuminated arena and custom computer vision software. Larval navigational decisions (when to turn) are modeled as the output a linear-nonlinear Poisson process. The development of the nonlinear turn rate in response to changes in variance is tracked using an adaptive point process filter determining the rate of adaptation to different stimulus profiles. Supported by NIH Grant 1DP2EB022359 and NSF Grant PHY-1455015.
An on-line monitoring system for navigation equipment
Wang, Bo; Yang, Ping; Liu, Jing; Yang, Zhengbo; Liang, Fei
2017-10-01
Civil air navigation equipment is the most important infrastructure of Civil Aviation, which is closely related to flight safety. In addition to regular flight inspection, navigation equipment's patrol measuring, maintenance measuring, running measuring under special weather conditions are the important means of ensuring aviation flight safety. According to the safety maintenance requirements of Civil Aviation Air Traffic Control navigation equipment, this paper developed one on-line monitoring system with independent intellectual property rights for navigation equipment, the system breakthroughs the key technologies of measuring navigation equipment on-line including Instrument Landing System (ILS) and VHF Omni-directional Range (VOR), which also meets the requirements of navigation equipment ground measurement set by the ICAO DOC 8071, it provides technical means of the ground on-line measurement for navigation equipment, improves the safety of navigation equipment operation, and reduces the impact of measuring navigation equipment on airport operation.
An Online Solution of LiDAR Scan Matching Aided Inertial Navigation System for Indoor Mobile Mapping
Niu, Xiaoji; Yu, Tong; Tang, Jian; Chang, Le
2017-01-01
Multisensors (LiDAR/IMU/CAMERA) integrated Simultaneous Location and Mapping (SLAM) technology for navigation and mobile mapping in a GNSS-denied environment, such as indoor areas, dense forests, or urban canyons, becomes a promising solution. An online (real-time) version of such system can extremely extend its applications, especially for indoor mobile mapping. However, the real-time response issue of multisensors is a big challenge for an online SLAM system, due to the different sampling f...
Cosmological perturbations in the projectable version of Hořava-Lifshitz gravity
Cerioni, Alessandro; Brandenberger, Robert H.
2011-01-01
We consider linear perturbations about a homogeneous and isotropic cosmological background in the projectable version of Hořava-Lifshitz gravity. Starting from the action for cosmological perturbations, we identify the canonically normalized fluctuation variables. We find that - in contrast to what happens in the non-projectable version of the theory - the extra scalar cosmological perturbation mode is already dynamical at the level of linear perturbations and is either ghost-like or tachyonic depending on the value of a free parameter. This indicates a problem for the projectable version of Hořava-Lifshitz gravity
Benchmark Framework for Mobile Robots Navigation Algorithms
Nelson David Muñoz-Ceballos
2014-01-01
Full Text Available Despite the wide variety of studies and research on mobile robot systems, performance metrics are not often examined. This makes difficult to establish an objective comparison of achievements. In this paper, the navigation of an autonomous mobile robot is evaluated. Several metrics are described. These metrics, collectively, provide an indication of navigation quality, useful for comparing and analyzing navigation algorithms of mobile robots. This method is suggested as an educational tool, which allows the student to optimize the algorithms quality, relating to important aspectsof science, technology and engineering teaching, as energy consumption, optimization and design.
Wavefront Propagation and Fuzzy Based Autonomous Navigation
Adel Al-Jumaily
2005-06-01
Full Text Available Path planning and obstacle avoidance are the two major issues in any navigation system. Wavefront propagation algorithm, as a good path planner, can be used to determine an optimal path. Obstacle avoidance can be achieved using possibility theory. Combining these two functions enable a robot to autonomously navigate to its destination. This paper presents the approach and results in implementing an autonomous navigation system for an indoor mobile robot. The system developed is based on a laser sensor used to retrieve data to update a two dimensional world model of therobot environment. Waypoints in the path are incorporated into the obstacle avoidance. Features such as ageing of objects and smooth motion planning are implemented to enhance efficiency and also to cater for dynamic environments.
Cloud Absorption Radiometer Autonomous Navigation System - CANS
Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan
2013-01-01
CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode
Mobile Robot Designed with Autonomous Navigation System
An, Feng; Chen, Qiang; Zha, Yanfang; Tao, Wenyin
2017-10-01
With the rapid development of robot technology, robots appear more and more in all aspects of life and social production, people also ask more requirements for the robot, one is that robot capable of autonomous navigation, can recognize the road. Take the common household sweeping robot as an example, which could avoid obstacles, clean the ground and automatically find the charging place; Another example is AGV tracking car, which can following the route and reach the destination successfully. This paper introduces a new type of robot navigation scheme: SLAM, which can build the environment map in a totally strange environment, and at the same time, locate its own position, so as to achieve autonomous navigation function.
Navigation of robotic system using cricket motes
Patil, Yogendra J.; Baine, Nicholas A.; Rattan, Kuldip S.
2011-06-01
This paper presents a novel algorithm for self-mapping of the cricket motes that can be used for indoor navigation of autonomous robotic systems. The cricket system is a wireless sensor network that can provide indoor localization service to its user via acoustic ranging techniques. The behavior of the ultrasonic transducer on the cricket mote is studied and the regions where satisfactorily distance measurements can be obtained are recorded. Placing the motes in these regions results fine-grain mapping of the cricket motes. Trilateration is used to obtain a rigid coordinate system, but is insufficient if the network is to be used for navigation. A modified SLAM algorithm is applied to overcome the shortcomings of trilateration. Finally, the self-mapped cricket motes can be used for navigation of autonomous robotic systems in an indoor location.
Orion Optical Navigation Progress Toward Exploration: Mission 1
Holt, Greg N.; D'Souza, Christopher N.; Saley, David
2018-01-01
Optical navigation of human spacecraft was proposed on Gemini and implemented successfully on Apollo as a means of autonomously operating the vehicle in the event of lost communication with controllers on Earth. It shares a history with the "method of lunar distances" that was used in the 18th century and gained some notoriety after its use by Captain James Cook during his 1768 Pacific voyage of the HMS Endeavor. The Orion emergency return system utilizing optical navigation has matured in design over the last several years, and is currently undergoing the final implementation and test phase in preparation for Exploration Mission 1 (EM-1) in 2019. The software development is being worked as a Government Furnished Equipment (GFE) project delivered as an application within the Core Flight Software of the Orion camera controller module. The mathematical formulation behind the initial ellipse fit in the image processing is detailed in Christian. The non-linear least squares refinement then follows the technique of Mortari as an estimation process of the planetary limb using the sigmoid function. The Orion optical navigation system uses a body fixed camera, a decision that was driven by mass and mechanism constraints. The general concept of operations involves a 2-hour pass once every 24 hours, with passes specifically placed before all maneuvers to supply accurate navigation information to guidance and targeting. The pass lengths are limited by thermal constraints on the vehicle since the OpNav attitude generally deviates from the thermally stable tail-to-sun attitude maintained during the rest of the orbit coast phase. Calibration is scheduled prior to every pass due to the unknown nature of thermal effects on the lens distortion and the mounting platform deformations between the camera and star trackers. The calibration technique is described in detail by Christian, et al. and simultaneously estimates the Brown-Conrady coefficients and the Star Tracker
Control and navigation system for a fixed-wing unmanned aerial vehicle
Ruiyong Zhai
2014-02-01
Full Text Available This paper presents a flight control and navigation system for a fixed-wing unmanned aerial vehicle (UAV with low-cost micro-electro-mechanical system (MEMS sensors. The system is designed under the inner loop and outer loop strategy. The trajectory tracking navigation loop is the outer loop of the attitude loop, while the attitude control loop is the outer loop of the stabilization loop. The proportional-integral-derivative (PID control was adopted for stabilization and attitude control. The three-dimensional (3D trajectory tracking control of a UAV could be approximately divided into lateral control and longitudinal control. The longitudinal control employs traditional linear PID feedback to achieve the desired altitude of the UAV, while the lateral control uses a non-linear control method to complete the desired trajectory. The non-linear controller can automatically adapt to ground velocity change, which is usually caused by gust disturbance, thus the UAV has good wind resistance characteristics. Flight tests and survey missions were carried out with our self-developed delta fixed-wing UAV and MEMS-based autopilot to confirm the effectiveness and practicality of the proposed navigation method.
Target Tracking with Sensor Navigation Using Coupled RSS and AoA Measurements
Slavisa Tomic
2017-11-01
Full Text Available This work addresses the problem of tracking a signal-emitting mobile target in wireless sensor networks (WSNs with navigated mobile sensors. The sensors are properly equipped to acquire received signal strength (RSS and angle of arrival (AoA measurements from the received signal, while the target transmit power is assumed not known. We start by showing how to linearize the highly non-linear measurement model. Then, by employing a Bayesian approach, we combine the linearized observation model with prior knowledge extracted from the state transition model. Based on the maximum a posteriori (MAP principle and the Kalman filtering (KF framework, we propose new MAP and KF algorithms, respectively. We also propose a simple and efficient mobile sensor navigation procedure, which allows us to further enhance the estimation accuracy of our algorithms with a reduced number of sensors. Model flaws, which result in imperfect knowledge about the path loss exponent (PLE and the true mobile sensors’ locations, are taken into consideration. We have carried out an extensive simulation study, and our results confirm the superiority of the proposed algorithms, as well as the effectiveness of the proposed navigation routine.
Lucy: Navigating a Jupiter Trojan Tour
Stanbridge, Dale; Williams, Ken; Williams, Bobby; Jackman, Coralie; Weaver, Hal; Berry, Kevin; Sutter, Brian; Englander, Jacob
2017-01-01
In January 2017, NASA selected the Lucy mission to explore six Jupiter Trojan asteroids. These six bodies, remnants of the primordial material that formed the outer planets, were captured in the Sun-Jupiter L4 and L5 Lagrangian regions early in the solar system formation. These particular bodies were chosen because of their diverse spectral properties and the chance to observe up close for the first time two orbiting approximately equal mass binaries, Patroclus and Menoetius. KinetX, Inc. is the primary navigation supplier for the Lucy mission. This paper describes preliminary navigation analyses of the approach phase for each Trojan encounter.
BOREAS Level-0 ER-2 Navigation Data
Strub, Richard; Dominguez, Roseanne; Newcomer, Jeffrey A.; Hall, Forrest G. (Editor)
2000-01-01
The BOREAS Staff Science effort covered those activities that were BOREAS community-level activities or required uniform data collection procedures across sites and time. These activities included the acquisition, processing, and archiving of aircraft navigation/attitude data to complement the digital image data. The level-0 ER-2 navigation data files contain aircraft attitude and position information acquired during the digital image and photographic data collection missions. Temporally, the data were acquired from April to September 1994. Data were recorded at intervals of 5 seconds. The data are stored in tabular ASCII files.
Navigation: bat orientation using Earth's magnetic field.
Holland, Richard A; Thorup, Kasper; Vonhof, Maarten J; Cochran, William W; Wikelski, Martin
2006-12-07
Bats famously orientate at night by echolocation, but this works over only a short range, and little is known about how they navigate over longer distances. Here we show that the homing behaviour of Eptesicus fuscus, known as the big brown bat, can be altered by artificially shifting the Earth's magnetic field, indicating that these bats rely on a magnetic compass to return to their home roost. This finding adds to the impressive array of sensory abilities possessed by this animal for navigation in the dark.
Navigation: Bat orientation using Earth's magnetic field
Holland, Richard A.; Thorup, Kasper; Vonhof, Maarten J.
2006-01-01
Bats famously orientate at night by echolocation 1 , but this works over only a short range, and little is known about how they navigate over longer distances 2 . Here we show that the homing behaviour of Eptesicus fuscus, known as the big brown bat, can be altered by artificially shifting the Ea...... the Earth's magnetic field, indicating that these bats rely on a magnetic compass to return to their home roost. This finding adds to the impressive array of sensory abilities possessed by this animal for navigation in the dark....
Pruess, K.; Oldenburg, C.M.; Moridis, G.J.
1999-01-01
TOUGH2 is a numerical simulator for nonisothermal flows of multicomponent, multiphase fluids in one, two, and three-dimensional porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, environmental assessment and remediation, and unsaturated and saturated zone hydrology. TOUGH2 was first released to the public in 1991; the 1991 code was updated in 1994 when a set of preconditioned conjugate gradient solvers was added to allow a more efficient solution of large problems. The current Version 2.0 features several new fluid property modules and offers enhanced process modeling capabilities, such as coupled reservoir-wellbore flow, precipitation and dissolution effects, and multiphase diffusion. Numerous improvements in previously released modules have been made and new user features have been added, such as enhanced linear equation solvers, and writing of graphics files. The T2VOC module for three-phase flows of water, air and a volatile organic chemical (VOC), and the T2DM module for hydrodynamic dispersion in 2-D flow systems have been integrated into the overall structure of the code and are included in the Version 2.0 package. Data inputs are upwardly compatible with the previous version. Coding changes were generally kept to a minimum, and were only made as needed to achieve the additional functionalities desired. TOUGH2 is written in standard FORTRAN77 and can be run on any platform, such as workstations, PCs, Macintosh, mainframe and supercomputers, for which appropriate FORTRAN compilers are available. This report is a self-contained guide to application of TOUGH2 to subsurface flow problems. It gives a technical description of the TOUGH2 code, including a discussion of the physical processes modeled, and the mathematical and numerical methods used. Illustrative sample problems are presented along with detailed instructions for preparing input data
Non linear system become linear system
Petre Bucur
2007-01-01
Full Text Available The present paper refers to the theory and the practice of the systems regarding non-linear systems and their applications. We aimed the integration of these systems to elaborate their response as well as to highlight some outstanding features.
Linear motor coil assembly and linear motor
2009-01-01
An ironless linear motor (5) comprising a magnet track (53) and a coil assembly (50) operating in cooperation with said magnet track (53) and having a plurality of concentrated multi-turn coils (31 a-f, 41 a-d, 51 a-k), wherein the end windings (31E) of the coils (31 a-f, 41 a-e) are substantially
A Statistical Review of CALIOP Version 3 and Version 4 Cloud Aerosol Discrimination
Zeng, S.
2016-12-01
The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission has now delivered a 10-year record of high-resolution profiles of backscatter at 532 nm and 1064 nm and linear depolarization at 532 nm. These long-term active sensor measurements at global scale have led to significant advances in our understanding of the vertical distribution of clouds and aerosols in the atmosphere. In the fall of 2016, the CALIPSO science team is scheduled to release a new version of their cloud and aerosol data products. The new cloud and aerosol discrimination products are derived using updated probability density functions that account for numerous improvements to the CALIOP calibration and the use of the GMAO MERRA-2 meteorological data. Moreover, the CAD algorithm is now applied to all layers detected, thus greatly improving the identification of such features as overshooting convective clouds, stratospheric aerosol layers, and high intensity dust storms. Post-processing modules are added to the standard CAD algorithm to ensure proper identification of (for example) the tenuous edges of cirrus clouds and water clouds lying beneath optically dense smoke layers. This work presents statistical comparisons between the CALIOP version 3 and version 4 data sets. Areas of improvement are highlighted, sources of continuing uncertainty are discussed and a list of best practices for data users is provided.
Navigation Problems in Blind-to-Blind Pedestrians Tele-assistance Navigation
Balata , Jan; Mikovec , Zdenek; Maly , Ivo
2015-01-01
International audience; We raise a question whether it is possible to build a large-scale navigation system for blind pedestrians where a blind person navigates another blind person remotely by mobile phone. We have conducted an experiment, in which we observed blind people navigating each other in a city center in 19 sessions. We focused on problems in the navigator’s attempts to direct the traveler to the destination. We observed 96 problems in total, classified them on the basis of the typ...
Wiedemann, H.
1981-11-01
Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center.
Blyth, T S
2002-01-01
Basic Linear Algebra is a text for first year students leading from concrete examples to abstract theorems, via tutorial-type exercises. More exercises (of the kind a student may expect in examination papers) are grouped at the end of each section. The book covers the most important basics of any first course on linear algebra, explaining the algebra of matrices with applications to analytic geometry, systems of linear equations, difference equations and complex numbers. Linear equations are treated via Hermite normal forms which provides a successful and concrete explanation of the notion of linear independence. Another important highlight is the connection between linear mappings and matrices leading to the change of basis theorem which opens the door to the notion of similarity. This new and revised edition features additional exercises and coverage of Cramer's rule (omitted from the first edition). However, it is the new, extra chapter on computer assistance that will be of particular interest to readers:...
Wiedemann, H.
1981-11-01
Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center
Napier, Bruce A.
2004-03-08
The GENII Version 2 computer code was developed for the Environmental Protection Agency (EPA) at Pacific Northwest National Laboratory (PNNL) to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) and the radiological risk estimating procedures of Federal Guidance Report 13 into updated versions of existing environmental pathway analysis models. The resulting environmental dosimetry computer codes are compiled in the GENII Environmental Dosimetry System. The GENII system was developed to provide a state-of-the-art, technically peer-reviewed, documented set of programs for calculating radiation dose and risk from radionuclides released to the environment. The codes were designed with the flexibility to accommodate input parameters for a wide variety of generic sites. Operation of a new version of the codes, GENII Version 2, is described in this report. Two versions of the GENII Version 2 code system are available, a full-featured version and a version specifically designed for demonstrating compliance with the dose limits specified in 40 CFR 61.93(a), the National Emission Standards for Hazardous Air Pollutants (NESHAPS) for radionuclides. The only differences lie in the limitation of the capabilities of the user to change specific parameters in the NESHAPS version. This report describes the data entry, accomplished via interactive, menu-driven user interfaces. Default exposure and consumption parameters are provided for both the average (population) and maximum individual; however, these may be modified by the user. Source term information may be entered as radionuclide release quantities for transport scenarios, or as basic radionuclide concentrations in environmental media (air, water, soil). For input of basic or derived concentrations, decay of parent radionuclides and ingrowth of radioactive decay products prior to the start of the exposure scenario may be considered. A single code run can
Matrices and linear transformations
Cullen, Charles G
1990-01-01
""Comprehensive . . . an excellent introduction to the subject."" - Electronic Engineer's Design Magazine.This introductory textbook, aimed at sophomore- and junior-level undergraduates in mathematics, engineering, and the physical sciences, offers a smooth, in-depth treatment of linear algebra and matrix theory. The major objects of study are matrices over an arbitrary field. Contents include Matrices and Linear Systems; Vector Spaces; Determinants; Linear Transformations; Similarity: Part I and Part II; Polynomials and Polynomial Matrices; Matrix Analysis; and Numerical Methods. The first
Efficient Non Linear Loudspeakers
Petersen, Bo R.; Agerkvist, Finn T.
2006-01-01
Loudspeakers have traditionally been designed to be as linear as possible. However, as techniques for compensating non linearities are emerging, it becomes possible to use other design criteria. This paper present and examines a new idea for improving the efficiency of loudspeakers at high levels...... by changing the voice coil layout. This deliberate non-linear design has the benefit that a smaller amplifier can be used, which has the benefit of reducing system cost as well as reducing power consumption....
Comparison between Linear and Nonlinear Regression in a Laboratory Heat Transfer Experiment
Gonçalves, Carine Messias; Schwaab, Marcio; Pinto, José Carlos
2013-01-01
In order to interpret laboratory experimental data, undergraduate students are used to perform linear regression through linearized versions of nonlinear models. However, the use of linearized models can lead to statistically biased parameter estimates. Even so, it is not an easy task to introduce nonlinear regression and show for the students…
Fusion of navigational data in River Information Services
Kazimierski, W.
2009-04-01
River Information Services (RIS) is the complex system of solutions and services for inland shipping. It has been the scope of works carried out in most of European countries for last several years. There were also a few major pan-European projects like INDRIS or COMPRIS launched for these purposes. The main idea of RIS is to harmonize the activities of various companies, authorities and other users of inland waterways in Europe. In the last time growing activity in this area in Poland can be also noticed. The leading example can be the works carried out in Chair of Geoinformatics in Maritime University of Szczecin regarding RIS for the needs of Odra River. The Directive 2005/44/EC of European Parliament and Europe Council, followed by European Commission regulations, give precise guidelines on implementing RIS in Europe, stating the services that should be provided. Among them Traffic Information and Traffic Management services can be found. As per guidelines they should be based on tracking and tracing of ships in the inland waters. The results of tracking and tracing are Tactical Traffic Image and Strategic Traffic Image. The guidelines stated that, tracking and tracing system in RIS shall consist of various type sensors. The most important of them is thought to be Automatic Information System (AIS), and particularly its river version - Inland AIS. It is based on determining the position of ships by satellite positioning systems (mainly DGPS) and transmitting it to other users on radio VHF frequences. This guarantees usually high accuracy of data related to movement of ships (assuming proper functioning of system and ship's sensors), and gives the possibility of transmitting additional information about ship, like dimensions, port of destination, cargo, etc. However the other sensors that can be used for tracking shall not be forgotten. The most important of them are radar (traditionally used for tracking purposes in Vessel Traffic Systems) and video camera
Faraway, Julian J
2014-01-01
A Hands-On Way to Learning Data AnalysisPart of the core of statistics, linear models are used to make predictions and explain the relationship between the response and the predictors. Understanding linear models is crucial to a broader competence in the practice of statistics. Linear Models with R, Second Edition explains how to use linear models in physical science, engineering, social science, and business applications. The book incorporates several improvements that reflect how the world of R has greatly expanded since the publication of the first edition.New to the Second EditionReorganiz
Carr, Joseph
1996-01-01
The linear IC market is large and growing, as is the demand for well trained technicians and engineers who understand how these devices work and how to apply them. Linear Integrated Circuits provides in-depth coverage of the devices and their operation, but not at the expense of practical applications in which linear devices figure prominently. This book is written for a wide readership from FE and first degree students, to hobbyists and professionals.Chapter 1 offers a general introduction that will provide students with the foundations of linear IC technology. From chapter 2 onwa
Fault tolerant linear actuator
Tesar, Delbert
2004-09-14
In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.
Superconducting linear accelerator cryostat
Ben-Zvi, I.; Elkonin, B.V.; Sokolowski, J.S.
1984-01-01
A large vertical cryostat for a superconducting linear accelerator using quarter wave resonators has been developed. The essential technical details, operational experience and performance are described. (author)
Linear mixed models a practical guide using statistical software
West, Brady T; Galecki, Andrzej T
2006-01-01
Simplifying the often confusing array of software programs for fitting linear mixed models (LMMs), Linear Mixed Models: A Practical Guide Using Statistical Software provides a basic introduction to primary concepts, notation, software implementation, model interpretation, and visualization of clustered and longitudinal data. This easy-to-navigate reference details the use of procedures for fitting LMMs in five popular statistical software packages: SAS, SPSS, Stata, R/S-plus, and HLM. The authors introduce basic theoretical concepts, present a heuristic approach to fitting LMMs based on bo
Adaptive Landmark-Based Navigation System Using Learning Techniques
Zeidan, Bassel; Dasgupta, Sakyasingha; Wörgötter, Florentin
2014-01-01
The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal. In...... hexapod robots. As a result, it allows the robots to successfully learn to navigate to distal goals in complex environments.......The goal-directed navigational ability of animals is an essential prerequisite for them to survive. They can learn to navigate to a distal goal in a complex environment. During this long-distance navigation, they exploit environmental features, like landmarks, to guide them towards their goal....... Inspired by this, we develop an adaptive landmark-based navigation system based on sequential reinforcement learning. In addition, correlation-based learning is also integrated into the system to improve learning performance. The proposed system has been applied to simulated simple wheeled and more complex...
GRIP DC-8 NAVIGATION AND HOUSEKEEPING DATA V1
National Aeronautics and Space Administration — The GRIP DC-8 Navigation and Housekeeping Data contains aircraft navigational data obtained during the GRIP campaign (15 Aug 2010 - 30 Sep 2010). The major goal was...
GRIP DC-8 NAVIGATION AND HOUSEKEEPING DATA V1
National Aeronautics and Space Administration — This dataset contains aircraft navigational data obtained during the GRIP campaign (15 Aug 2010 - 30 Sep 2010). The NASA DC-8 is outfitted with a navigational...
Issues in symbol design for electronic displays of navigation information
2004-10-24
An increasing number of electronic displays, ranging from small hand-held displays for general aviation to installed displays for air transport, are showing navigation information, such as symbols representing navigational aids. The wide range of dis...
GPM Ground Validation Navigation Data ER-2 OLYMPEX V1
National Aeronautics and Space Administration — The GPM Ground Validation NASA ER-2 Navigation Data OLYMPEX dataset supplies navigation data collected by the NASA ER-2 aircraft for flights that occurred during...
Enabling Autonomous Navigation for Affordable Scooters
Kaikai Liu
2018-06-01
Full Text Available Despite the technical success of existing assistive technologies, for example, electric wheelchairs and scooters, they are still far from effective enough in helping those in need navigate to their destinations in a hassle-free manner. In this paper, we propose to improve the safety and autonomy of navigation by designing a cutting-edge autonomous scooter, thus allowing people with mobility challenges to ambulate independently and safely in possibly unfamiliar surroundings. We focus on indoor navigation scenarios for the autonomous scooter where the current location, maps, and nearby obstacles are unknown. To achieve semi-LiDAR functionality, we leverage the gyros-based pose data to compensate the laser motion in real time and create synthetic mapping of simple environments with regular shapes and deep hallways. Laser range finders are suitable for long ranges with limited resolution. Stereo vision, on the other hand, provides 3D structural data of nearby complex objects. To achieve simultaneous fine-grained resolution and long range coverage in the mapping of cluttered and complex environments, we dynamically fuse the measurements from the stereo vision camera system, the synthetic laser scanner, and the LiDAR. We propose solutions to self-correct errors in data fusion and create a hybrid map to assist the scooter in achieving collision-free navigation in an indoor environment.
Enabling Autonomous Navigation for Affordable Scooters.
Liu, Kaikai; Mulky, Rajathswaroop
2018-06-05
Despite the technical success of existing assistive technologies, for example, electric wheelchairs and scooters, they are still far from effective enough in helping those in need navigate to their destinations in a hassle-free manner. In this paper, we propose to improve the safety and autonomy of navigation by designing a cutting-edge autonomous scooter, thus allowing people with mobility challenges to ambulate independently and safely in possibly unfamiliar surroundings. We focus on indoor navigation scenarios for the autonomous scooter where the current location, maps, and nearby obstacles are unknown. To achieve semi-LiDAR functionality, we leverage the gyros-based pose data to compensate the laser motion in real time and create synthetic mapping of simple environments with regular shapes and deep hallways. Laser range finders are suitable for long ranges with limited resolution. Stereo vision, on the other hand, provides 3D structural data of nearby complex objects. To achieve simultaneous fine-grained resolution and long range coverage in the mapping of cluttered and complex environments, we dynamically fuse the measurements from the stereo vision camera system, the synthetic laser scanner, and the LiDAR. We propose solutions to self-correct errors in data fusion and create a hybrid map to assist the scooter in achieving collision-free navigation in an indoor environment.
Gamifying Navigation in Location-Based Applications
Nadarajah, Stephanie Githa; Overgaard, Benjamin Nicholas; Pedersen, Peder Walz
2017-01-01
Location-based games entertain players usually by interactions at points of interest (POIs). Navigation between POIs often involve the use of either a physical or digital map, not taking advantage of the opportunity available to engage users in activities between POIs. The paper presents riddle s...
Navigation in musculoskeletal oncology: An overview
Guy Vernon Morris
2018-01-01
Full Text Available Navigation in surgery has increasingly become more commonplace. The use of this technological advancement has enabled ever more complex and detailed surgery to be performed to the benefit of surgeons and patients alike. This is particularly so when applying the use of navigation within the field of orthopedic oncology. The developments in computer processing power coupled with the improvements in scanning technologies have permitted the incorporation of navigational procedures into day-to-day practice. A comprehensive search of PubMed using the search terms “navigation”, “orthopaedic” and “oncology” yielded 97 results. After filtering for English language papers, excluding spinal surgery and review articles, this resulted in 38 clinical studies and case reports. These were analyzed in detail by the authors (GM and JS and the most relevant papers reviewed. We have sought to provide an overview of the main types of navigation systems currently available within orthopedic oncology and to assess some of the evidence behind its use.
Ohio River Navigation: Past-Present-Future
1979-10-01
navigation structures had been built: the auxillary 56- by 360-foot lock at dam 41 (Louisville), 1930; Montgomery Locks and Dam, 1936; and Gallipolis...Mile 974.2. This project was approved in 1963, but substantial ’ delay is anticipated ina decision concerning its execu- tion. For this reason a
Mobile Screens: The Visual Regime of Navigation
Verhoeff, N.
2012-01-01
In this book on screen media, space, and mobility I compare synchronically, as well as diachronically, diverse and variegated screen media - their technologies and practices – as sites for virtual mobility and navigation. Mobility as a central trope can be found on the multiple levels that are
The "Set Map" Method of Navigation.
Tippett, Julian
1998-01-01
Explains the "set map" method of using the baseplate compass to solve walkers' navigational needs as opposed to the 1-2-3 method for taking a bearing. The map, with the compass permanently clipped to it, is rotated to the position in which its features have the same orientation as their counterparts on the ground. Includes directions and…
Neurosurgical robotic arm drilling navigation system.
Lin, Chung-Chih; Lin, Hsin-Cheng; Lee, Wen-Yo; Lee, Shih-Tseng; Wu, Chieh-Tsai
2017-09-01
The aim of this work was to develop a neurosurgical robotic arm drilling navigation system that provides assistance throughout the complete bone drilling process. The system comprised neurosurgical robotic arm navigation combining robotic and surgical navigation, 3D medical imaging based surgical planning that could identify lesion location and plan the surgical path on 3D images, and automatic bone drilling control that would stop drilling when the bone was to be drilled-through. Three kinds of experiment were designed. The average positioning error deduced from 3D images of the robotic arm was 0.502 ± 0.069 mm. The correlation between automatically and manually planned paths was 0.975. The average distance error between automatically planned paths and risky zones was 0.279 ± 0.401 mm. The drilling auto-stopping algorithm had 0.00% unstopped cases (26.32% in control group 1) and 70.53% non-drilled-through cases (8.42% and 4.21% in control groups 1 and 2). The system may be useful for neurosurgical robotic arm drilling navigation. Copyright © 2016 John Wiley & Sons, Ltd.
77 FR 67658 - Navigation Safety Advisory Council
2012-11-13
... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2012-0212] Navigation Safety Advisory.../en/hotels/florida/embassy-suites-tampa-downtown-convention-center-TPAESES/index.html . For... possible. To facilitate public participation, we are inviting public comment on the issues to be considered...
Orchard navigation using derivative free Kalman filtering
Hansen, Søren; Bayramoglu, Enis; Andersen, Jens Christian
2011-01-01
This paper describes the use of derivative free filters for mobile robot localization and navigation in an orchard. The localization algorithm fuses odometry and gyro measurements with line features representing the surrounding fruit trees of the orchard. The line features are created on basis of 2...
Cloud-Induced Uncertainty for Visual Navigation
2014-12-26
can occur due to interference, jamming, or signal blockage in urban canyons. In GPS-denied environments, a GP- S/INS navigation system is forced to rely...physics-based approaches use equations that model fluid flow, thermodynamics, water condensation , and evapora- tion to generate clouds [4]. The drawback
Requirements for e-Navigation Architectures
Axel Hahn
2016-12-01
Full Text Available Technology is changing the way of navigation. New technologies for communication and navigation can be found on virtually every vessel. System architectures define structure and cooperation of components and subsystems. IMO, IALA, costal authorities, technology provider and many more actually propose new architectures for e-Navigation. This paper looks at other transportation domains and technical as normative requirements for e-Navigation architectures. With the aim of identifying possible synergies in the research, development, certification and standardization, this paper sets out to compare requirements and approaches of these two domains with respect to safety and security aspects. Since from an autonomy perspective, the automotive domain has started earlier and therefore has achieved a higher degree of technical progress, we will start with an overview of the developments in this domain. After that, the paper discusses the requirements on automation and assistance systems in the maritime domain and gives an overview of the developments into this direction within the maritime domain. This then allows us to compare developments in both domains and to derive recommendations for further developments in the maritime domain at the end of this paper.
'Outsmarting Traffic, Together': Driving as Social Navigation
Sam Hind
2014-04-01
Full Text Available The automotive world is evolving. Ten years ago Nigel Thrift (2004: 41 made the claim that the experience of driving was slipping into our 'technological unconscious'. Only recently the New York Times suggested that with the rise of automated driving, standalone navigation tools as we know them would cease to exist, instead being 'fully absorbed into the machine' (Fisher, 2013. But in order to bridge the gap between past and future driving worlds, another technological evolution is emerging. This short, critical piece charts the rise of what has been called 'social navigation' in the industry; the development of digital mapping platforms designed to foster automotive sociality. It makes two provisional points. Firstly, that 'ludic' conceptualisations can shed light on the ongoing reconfiguration of drivers, vehicles, roads and technological aids such as touch-screen satellite navigation platforms. And secondly, that as a result of this, there is a coming-into-being of a new kind of driving politics; a 'casual politicking' centred on an engagement with digital interfaces. We explicate both by turning our attention towards Waze; a social navigation application that encourages users to interact with various driving dynamics.
Celestial Navigation on the Surface of Mars
Malay, Benjamin P.
2001-05-01
A simple, accurate, and autonomous method of finding position on the surface of Mars currently does not exist. The goal of this project is to develop a celestial navigation process that will fix a position on Mars with 100-meter accuracy. This method requires knowing the position of the stars and planets referenced to the Martian surface with one arcsecond accuracy. This information is contained in an ephemeris known as the Aeronautical Almanac (from Ares, the god of war) . Naval Observatory Vector Astrometry Subroutines (NOVAS) form the basis of the code used to generate the almanac. Planetary position data come the JPL DE405 Planetary Ephemeris. The theoretical accuracy of the almanac is determined mathematically and compared with the Ephemeris for Physical Observations of Mars contained in the Astronautical Almanac. A preliminary design of an autonomous celestial navigation system is presented. Recommendations of how to integrate celestial navigation into NASA=s current Mars exploration program are also discussed. This project is a useful and much-needed first step towards establishing celestial navigation as a practical way to find position on the surface of Mars.
Autonomous Rule Based Robot Navigation In Orchards
Andersen, Jens Christian; Ravn, Ole; Andersen, Nils Axel
2010-01-01
Orchard navigation using sensor-based localization and exible mission management facilitates successful missions independent of the Global Positioning System (GPS). This is especially important while driving between tight tree rows where the GPS coverage is poor. This paper suggests localization ...
Navigating Transitions: Challenges for Engineering Students
Moore-Russo, Deborah; Wilsey, Jillian N.; Parthum, Michael J., Sr.; Lewis, Kemper
2017-01-01
As college students enter engineering, they face challenges when they navigate across various transitions. These challenges impact whether a student can successfully adapt to the rigorous curricular requirements of an engineering degree and to the norms and expectations that are particular to engineering. This article focuses on the transitions…
Navigable windows of the Northwest Passage
Liu, Xing-he; Ma, Long; Wang, Jia-yue; Wang, Ye; Wang, Li-na
2017-09-01
Artic sea ice loss trends support a greater potential for Arctic shipping. The information of sea ice conditions is important for utilizing Arctic passages. Based on the shipping routes given by ;Arctic Marine Shipping Assessment 2009 Report;, the navigable windows of these routes and the constituent legs were calculated by using sea ice concentration product data from 2006 to 2015, by which a comprehensive knowledge of the sea ice condition of the Northwest Passage was achieved. The results showed that Route 4 (Lancaster Sound - Barrow Strait - Prince Regent Inlet and Bellot Strait - Franklin Strait - Larsen Sound - Victoria Strait - Queen Maud Gulf - Dease Strait - Coronation Gulf - Dolphin and Union Strait - Amundsen Gulf) had the best navigable expectation, Route 2 (Parry Channel - M'Clure Strait) had the worst, and the critical legs affecting the navigation of Northwest Passage were Viscount Melville Sound, Franklin Strait, Victoria Strait, Bellot Strait, M'Clure Strait and Prince of Wales Strait. The shortest navigable period of the routes of Northwest Passage was up to 69 days. The methods used and the results of the study can help the selection and evaluation of Arctic commercial routes.
The Navigation Metaphor in Security Economics
Pieters, W.; Barendse, Jeroen; Ford, Margaret; Heath, Claude P R; Probst, Christian W.; Verbij, Ruud
2016-01-01
The navigation metaphor for cybersecurity merges security architecture models and security economics. By identifying the most efficient routes for gaining access to assets from an attacker's viewpoint, an organization can optimize its defenses along these routes. The well-understood concept of
The navigation metaphor in security economics
Pieters, Wolter; Barendse, Jeroen; Ford, Margaret; Heath, Claude P.R.; Probst, Christian W.; Verbij, Ruud
2016-01-01
The navigation metaphor for cybersecurity merges security architecture models and security economics. By identifying the most efficient routes for gaining access to assets from an attacker's viewpoint, an organization can optimize its defenses along these routes. The well-understood concept of
Spatial navigation by congenitally blind individuals.
Schinazi, Victor R; Thrash, Tyler; Chebat, Daniel-Robert
2016-01-01
Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergent, cumulative, and persistent). Recent advances in neuroscience and technological devices have provided novel insights into the different neural mechanisms underlying spatial navigation by blind and sighted people and the potential for functional reorganization. Despite these advances, there is still a lack of consensus regarding the extent to which locomotion and wayfinding depend on amodal spatial representations. This challenge largely stems from methodological limitations such as heterogeneity in the blind population and terminological ambiguity related to the concept of cognitive maps. Coupled with an over-reliance on potential technological solutions, the field has diffused into theoretical and applied branches that do not always communicate. Here, we review research on navigation by congenitally blind individuals with an emphasis on behavioral and neuroscientific evidence, as well as the potential of technological assistance. Throughout the article, we emphasize the need to disentangle strategy choice and performance when discussing the navigation abilities of the blind population. For further resources related to this article, please visit the WIREs website. © 2015 The Authors. WIREs Cognitive Science published by Wiley Periodicals, Inc.
Robust Pedestrian Navigation for Challenging Applications
Gilliéron, PY; Renaudin, V
2009-01-01
Presentation of a concept for robust indoor navigation. The concept is based on three key elements: - the use of an absolute geographical reference - the hybridisation of complementary technologies - specific motion models. This concept is illustrated by the means of two applications: the urban displacement of blind people and the indoor guidance of fire-fighters
From translation to navigation of different discourses
Livonen, Mirja; Sonnenwald, Diane H.
1998-01-01
' 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 search term...
Navigating the Bio-Politics of Childhood
Lee, Nick; Motzkau, Johanna
2011-01-01
Childhood research has long shared a bio-political terrain with state agencies in which children figure primarily as "human futures". In the 20th century bio-social dualism helped to make that terrain navigable by researchers, but, as life processes increasingly become key sites of bio-political action, bio-social dualism is becoming…
A GPS inspired Terrain Referenced Navigation algorithm
Vaman, D.
2014-01-01
Terrain Referenced Navigation (TRN) refers to a form of localization in which measurements of distances to the terrain surface are matched with a digital elevation map allowing a vehicle to estimate its own position within the map. The main goal of this dissertation is to improve TRN performance
Davidson, J.R.
1995-12-01
Evaluating the need for and the effectiveness of remedial cleanup at waste sites often includes finding average contaminant concentrations and identifying pockets of contamination called hot spots. The standard tool for calculating the probability of detecting pockets of contamination called hot spots has been the ELIPGRID code of singer and Wickman. The ELIPGRID-PC program has recently made this algorithm available for an IBM reg-sign personal computer (PC) or compatible. A new version of ELIPGRID-PC, incorporating Monte Carlo test results and simple graphics, is herein described. Various examples of how to use the program for both single and multiple hot spot cases are given. The code for an American National Standards Institute C version of the ELIPGRID algorithm is provided, and limitations and further work are noted. This version of ELIPGRID-PC reliably meets the goal of moving Singer's ELIPGRID algorithm to the PC
[Fetal version as ambulatory intervention].
Nohe, G; Hartmann, W; Klapproth, C E
1996-06-01
The external cephalic version (ECV) of the fetus at term reduces the maternal and fetal risks of intrapartum breech presentation and Caesarean delivery. Since 1986 over 800 external cephalic versions were performed in the outpatient Department of Obstetrics and Gynaecology of the Städtische Frauenklinik Stuttgart. 60.5% were successful. NO severe complications occurred. Sufficient amniotic fluid as well as the mobility of the fetal breech is a major criterion for the success of the ECV. Management requires a safe technique for mother and fetus. This includes ultrasonography, elektronic fetal monitoring and the ability to perform immediate caesarean delivery as well as the performance of ECV without analgesicas and sedatives. More than 70% of the ECV were successful without tocolysis. In unsuccessful cases the additional use of tocolysis improves the success rate only slightly. Therefore routine use of tocolysis does not appear necessary. External cephalic version can be recommended as an outpatient treatment without tocolysis.
Navigated Waterways of Louisiana, Geographic NAD83, LOSCO (1999) [navigated_waterways_LOSCO_1999
Louisiana Geographic Information Center — This is a line dataset of navigated waterways fitting the LOSCO definition: it has been traveled by vessels transporting 10,000 gallons of oil or fuel as determined...
National Aeronautics and Space Administration — Microcosm will use existing hardware and software from related programs to create a prototype Lunar Navigation Sensor (LNS) early in Phase II, such that most of the...
Vision/INS Integrated Navigation System for Poor Vision Navigation Environments
Youngsun Kim
2016-10-01
Full Text Available In order to improve the performance of an inertial navigation system, many aiding sensors can be used. Among these aiding sensors, a vision sensor is of particular note due to its benefits in terms of weight, cost, and power consumption. This paper proposes an inertial and vision integrated navigation method for poor vision navigation environments. The proposed method uses focal plane measurements of landmarks in order to provide position, velocity and attitude outputs even when the number of landmarks on the focal plane is not enough for navigation. In order to verify the proposed method, computer simulations and van tests are carried out. The results show that the proposed method gives accurate and reliable position, velocity and attitude outputs when the number of landmarks is insufficient.
National Aeronautics and Space Administration — Microcosm proposes to design and develop a fully autonomous Lunar Navigator based on our MicroMak miniature star sensor and a gravity gradiometer similar to one on a...
Yunes Sh. ALQUDSI
2018-06-01
Full Text Available This paper discusses and presents an overview of the proportional navigation (PN guidance law as well as the differential geometry (DG guidance algorithm that are used to develop the intercept course of a certain target. The intent of this study is to illustrate the advantages of the guidance algorithm generated based on the concepts of differential geometry against the well-known PN guidance law. The basic principles behind the both algorithms are mentioned. Moreover, the different versions of the PN approach is briefly clarified to show the essential improvement from one version to the other. The paper terminated with numerous two-dimension simulation figures to give a great value of visual aids, illustrating the significant relations and main features and properties of both algorithms.
Patten, B.C.
1983-04-01
Two issues concerning linearity or nonlinearity of natural systems are considered. Each is related to one of the two alternative defining properties of linear systems, superposition and decomposition. Superposition exists when a linear combination of inputs to a system results in the same linear combination of outputs that individually correspond to the original inputs. To demonstrate this property it is necessary that all initial states and inputs of the system which impinge on the output in question be included in the linear combination manipulation. As this is difficult or impossible to do with real systems of any complexity, nature appears nonlinear even though it may be linear. A linear system that displays nonlinear behavior for this reason is termed pseudononlinear. The decomposition property exists when the dynamic response of a system can be partitioned into an input-free portion due to state plus a state-free portion due to input. This is a characteristic of all linear systems, but not of nonlinear systems. Without the decomposition property, it is not possible to distinguish which portions of a system's behavior are due to innate characteristics (self) vs. outside conditions (environment), which is an important class of questions in biology and ecology. Some philosophical aspects of these findings are then considered. It is suggested that those ecologists who hold to the view that organisms and their environments are separate entities are in effect embracing a linear view of nature, even though their belief systems and mathematical models tend to be nonlinear. On the other hand, those who consider that organism-environment complex forms a single inseparable unit are implictly involved in non-linear thought, which may be in conflict with the linear modes and models that some of them use. The need to rectify these ambivalences on the part of both groups is indicated.
Evaluation of navigation interfaces in virtual environments
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.
Discrete-State-Based Vision Navigation Control Algorithm for One Bipedal Robot
Dunwen Wei
2015-01-01
Full Text Available Navigation with the specific objective can be defined by specifying desired timed trajectory. The concept of desired direction field is proposed to deal with such navigation problem. To lay down a principled discussion of the accuracy and efficiency of navigation algorithms, strictly quantitative definitions of tracking error, actuator effect, and time efficiency are established. In this paper, one vision navigation control method based on desired direction field is proposed. This proposed method uses discrete image sequences to form discrete state space, which is especially suitable for bipedal walking robots with single camera walking on a free-barrier plane surface to track the specific objective without overshoot. The shortest path method (SPM is proposed to design such direction field with the highest time efficiency. However, one improved control method called canonical piecewise-linear function (PLF is proposed. In order to restrain the noise disturbance from the camera sensor, the band width control method is presented to significantly decrease the error influence. The robustness and efficiency of the proposed algorithm are illustrated through a number of computer simulations considering the error from camera sensor. Simulation results show that the robustness and efficiency can be balanced by choosing the proper controlling value of band width.
Rose, Michael Benjamin
A novel trajectory and attitude control and navigation analysis tool for powered ascent is developed. The tool is capable of rapid trade-space analysis and is designed to ultimately reduce turnaround time for launch vehicle design, mission planning, and redesign work. It is streamlined to quickly determine trajectory and attitude control dispersions, propellant dispersions, orbit insertion dispersions, and navigation errors and their sensitivities to sensor errors, actuator execution uncertainties, and random disturbances. The tool is developed by applying both Monte Carlo and linear covariance analysis techniques to a closed-loop, launch vehicle guidance, navigation, and control (GN&C) system. The nonlinear dynamics and flight GN&C software models of a closed-loop, six-degree-of-freedom (6-DOF), Monte Carlo simulation are formulated and developed. The nominal reference trajectory (NRT) for the proposed lunar ascent trajectory is defined and generated. The Monte Carlo truth models and GN&C algorithms are linearized about the NRT, the linear covariance equations are formulated, and the linear covariance simulation is developed. The performance of the launch vehicle GN&C system is evaluated using both Monte Carlo and linear covariance techniques and their trajectory and attitude control dispersion, propellant dispersion, orbit insertion dispersion, and navigation error results are validated and compared. Statistical results from linear covariance analysis are generally within 10% of Monte Carlo results, and in most cases the differences are less than 5%. This is an excellent result given the many complex nonlinearities that are embedded in the ascent GN&C problem. Moreover, the real value of this tool lies in its speed, where the linear covariance simulation is 1036.62 times faster than the Monte Carlo simulation. Although the application and results presented are for a lunar, single-stage-to-orbit (SSTO), ascent vehicle, the tools, techniques, and mathematical
Sarkaer, M.; San Segundo Bello, D.; Van Hoof, C.; Theuwissen, A.
2010-01-01
The navigational strategies of insects using skylight polarization are interesting for applications in autonomous agent navigation because they rely on very little information for navigation. A polarization navigation sensor using the Stokes parameters to determine the orientation is presented. The
22 CFR 401.25 - Government brief regarding navigable waters.
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Government brief regarding navigable waters. 401... PROCEDURE Applications § 401.25 Government brief regarding navigable waters. When in the opinion of the Commission it is desirable that a decision should be rendered which affects navigable waters in a manner or...
Gray and White Matter Correlates of Navigational Ability in Humans
Wegman, J.B.T.; Fonteijn, H.M.; Ekert, J. van; Tyborowska, A.B.; Jansen, C.; Janzen, G.
2014-01-01
Humans differ widely in their navigational abilities. Studies have shown that self-reports on navigational abilities are good predictors of performance on navigation tasks in real and virtual environments. The caudate nucleus and medial temporal lobe regions have been suggested to subserve different
PRIVATE GRAPHS – ACCESS RIGHTS ON GRAPHS FOR SEAMLESS NAVIGATION
W. Dorner
2016-06-01
Full Text Available After the success of GNSS (Global Navigational Satellite Systems and navigation services for public streets, indoor seems to be the next big development in navigational services, relying on RTLS – Real Time Locating Services (e.g. WIFI and allowing seamless navigation. In contrast to navigation and routing services on public streets, seamless navigation will cause an additional challenge: how to make routing data accessible to defined users or restrict access rights for defined areas or only to parts of the graph to a defined user group? The paper will present case studies and data from literature, where seamless and especially indoor navigation solutions are presented (hospitals, industrial complexes, building sites, but the problem of restricted access rights was only touched from a real world, but not a technical perspective. The analysis of case studies will show, that the objective of navigation and the different target groups for navigation solutions will demand well defined access rights and require solutions, how to make only parts of a graph to a user or application available to solve a navigational task. The paper will therefore introduce the concept of private graphs, which is defined as a graph for navigational purposes covering the street, road or floor network of an area behind a public street and suggest different approaches how to make graph data for navigational purposes available considering access rights and data protection, privacy and security issues as well.
76 FR 27337 - Houston/Galveston Navigation Safety Advisory Committee
2011-05-11
... DEPARTMENT OF HOMELAND SECURITY Coast Guard [USCG-2010-1116] Houston/Galveston Navigation Safety...: The Houston/Galveston Navigation Safety Advisory Committee postponed its originally scheduled February... Houston Ship Channel, and various other navigation safety matters in the Galveston Bay area. The meeting...
Benefits of multisensory presentation on perception, memory and navigation
Philippi, T.G.|info:eu-repo/dai/nl/313711577
2012-01-01
Navigation is the process of planning and following routes to travel from the current location to a target location. In comparison with real world navigation, we have considerable difficulty with navigation in virtual environments. An important cause is that less information is presented in a
76 FR 58105 - Regulated Navigation Area; Saugus River, Lynn, MA
2011-09-20
... final rule. SUMMARY: The Coast Guard is establishing a Regulated Navigation Area (RNA) on the navigable... INFORMATION: Regulatory Information The Coast Guard is issuing this temporary rule without prior notice and... Pipeline bridge poses to the navigational channel necessitates that all mariners comply with this RNA...
Time and Motion Study of a Community Patient Navigator
Sara S. Phillips
2014-04-01
Full Text Available Research on patient navigation has focused on validating the utility of navigators by defining their roles and analyzing their effects on patient outcomes, patient satisfaction, and cost effectiveness. Patient navigators are increasingly used outside the research context, and their roles without research responsibilities may look very different. This pilot study captured the activities of a community patient navigator for uninsured women with a positive screening test for breast cancer, using a time and motion approach over a period of three days. We followed the actions of this navigator minute by minute to assess the relative ratios of actions performed and to identify areas for time efficiency improvement to increase direct time with patients. This novel approach depicts the duties of a community patient navigator no longer fettered by navigation logs, research team meetings, surveys, and the consent process. We found that the community patient navigator was able to spend more time with patients in the clinical context relative to performing paperwork or logging communication with patients as a result of her lack of research responsibilities. By illuminating how community patient navigation functions as separate from the research setting, our results will inform future hiring and training of community patient navigators, system design and operations for improving the efficiency and efficacy of navigators, and our understanding of what community patient navigators do in the absence of research responsibilities.
Linear colliders - prospects 1985
Rees, J.
1985-06-01
We discuss the scaling laws of linear colliders and their consequences for accelerator design. We then report on the SLAC Linear Collider project and comment on experience gained on that project and its application to future colliders. 9 refs., 2 figs
Richter, B.
1985-01-01
A report is given on the goals and progress of the SLAC Linear Collider. The author discusses the status of the machine and the detectors and give an overview of the physics which can be done at this new facility. He also gives some ideas on how (and why) large linear colliders of the future should be built
Rogner, H.H.
1989-01-01
The submitted sections on linear programming are extracted from 'Theorie und Technik der Planung' (1978) by W. Blaas and P. Henseler and reformulated for presentation at the Workshop. They consider a brief introduction to the theory of linear programming and to some essential aspects of the SIMPLEX solution algorithm for the purposes of economic planning processes. 1 fig
Rowe, C.H.; Wilton, M.S. de.
1979-01-01
An improved recirculating electron beam linear accelerator of the racetrack type is described. The system comprises a beam path of four straight legs with four Pretzel bending magnets at the end of each leg to direct the beam into the next leg of the beam path. At least one of the beam path legs includes a linear accelerator. (UK)
Walker, M.
2012-05-01
Significant differences in the rotation of the celestial dome between the tropical and temperate zones did not stop the peoples of either the tropical Pacific or temperate Europe from using geocentric astronomy to guide exploration of the oceans. Although the differences in the night sky contributed to differences between the Pacific Island and European systems for navigation at sea, the two navigation systems exhibit substantial similarities. Both systems define positions on the surface of the Earth using two coordinates that vary at right angles to each other and use stars, and to a lesser extent the sun, to determine directions. This essay explores similarities and differences in the use of geocentric astronomy for navigation at sea by the peoples of Polynesia and Europe in the late eighteenth century. Captain Cook's orders to discover the unknown southern continent after observing the transit of Venus combined with differences in language and culture to obscure the deeper similarities between the navigation systems used by Cook and the Polynesians. Although it was a further 200 years before anthropologists studied Pacific navigation, collaborations in voyaging with communities in Oceania demonstrated the effectiveness of Pacific navigation systems, revived interest in traditional voyaging in island communities around the Pacific, and potentially open the way for further collaborations in other areas.
Semidefinite linear complementarity problems
Eckhardt, U.
1978-04-01
Semidefinite linear complementarity problems arise by discretization of variational inequalities describing e.g. elastic contact problems, free boundary value problems etc. In the present paper linear complementarity problems are introduced and the theory as well as the numerical treatment of them are described. In the special case of semidefinite linear complementarity problems a numerical method is presented which combines the advantages of elimination and iteration methods without suffering from their drawbacks. This new method has very attractive properties since it has a high degree of invariance with respect to the representation of the set of all feasible solutions of a linear complementarity problem by linear inequalities. By means of some practical applications the properties of the new method are demonstrated. (orig.) [de
Handbook on linear motor application
1988-10-01
This book guides the application for Linear motor. It lists classification and speciality of Linear Motor, terms of linear-induction motor, principle of the Motor, types on one-side linear-induction motor, bilateral linear-induction motor, linear-DC Motor on basic of the motor, linear-DC Motor for moving-coil type, linear-DC motor for permanent-magnet moving type, linear-DC motor for electricity non-utility type, linear-pulse motor for variable motor, linear-pulse motor for permanent magneto type, linear-vibration actuator, linear-vibration actuator for moving-coil type, linear synchronous motor, linear electromagnetic motor, linear electromagnetic solenoid, technical organization and magnetic levitation and linear motor and sensor.
ALPS - A LINEAR PROGRAM SOLVER
Viterna, L. A.
1994-01-01
Linear programming is a widely-used engineering and management tool. Scheduling, resource allocation, and production planning are all well-known applications of linear programs (LP's). Most LP's are too large to be solved by hand, so over the decades many computer codes for solving LP's have been developed. ALPS, A Linear Program Solver, is a full-featured LP analysis program. ALPS can solve plain linear programs as well as more complicated mixed integer and pure integer programs. ALPS also contains an efficient solution technique for pure binary (0-1 integer) programs. One of the many weaknesses of LP solvers is the lack of interaction with the user. ALPS is a menu-driven program with no special commands or keywords to learn. In addition, ALPS contains a full-screen editor to enter and maintain the LP formulation. These formulations can be written to and read from plain ASCII files for portability. For those less experienced in LP formulation, ALPS contains a problem "parser" which checks the formulation for errors. ALPS creates fully formatted, readable reports that can be sent to a printer or output file. ALPS is written entirely in IBM's APL2/PC product, Version 1.01. The APL2 workspace containing all the ALPS code can be run on any APL2/PC system (AT or 386). On a 32-bit system, this configuration can take advantage of all extended memory. The user can also examine and modify the ALPS code. The APL2 workspace has also been "packed" to be run on any DOS system (without APL2) as a stand-alone "EXE" file, but has limited memory capacity on a 640K system. A numeric coprocessor (80X87) is optional but recommended. The standard distribution medium for ALPS is a 5.25 inch 360K MS-DOS format diskette. IBM, IBM PC and IBM APL2 are registered trademarks of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation.
Linearization of Nonautonomous Impulsive System with Nonuniform Exponential Dichotomy
Yongfei Gao
2014-01-01
Full Text Available This paper gives a version of Hartman-Grobman theorem for the impulsive differential equations. We assume that the linear impulsive system has a nonuniform exponential dichotomy. Under some suitable conditions, we proved that the nonlinear impulsive system is topologically conjugated to its linear system. Indeed, we do construct the topologically equivalent function (the transformation. Moreover, the method to prove the topological conjugacy is quite different from those in previous works (e.g., see Barreira and Valls, 2006.
SLS Navigation Model-Based Design Approach
Oliver, T. Emerson; Anzalone, Evan; Geohagan, Kevin; Bernard, Bill; Park, Thomas
2018-01-01
The SLS Program chose to implement a Model-based Design and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team has been responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for the navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1-B design, the additional GPS Receiver hardware is managed as a DMM at the vehicle design level. This paper provides a discussion of the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the Navigation components. These include composing system requirements, requirements verification, model development, model verification and validation, and modeling and analysis approaches. The Model-based Design and Requirements approach does not reduce the effort associated with the design process versus previous processes used at Marshall Space Flight Center. Instead, the approach takes advantage of overlap between the requirements development and management process, and the design and analysis process by efficiently combining the control (i.e. the requirement) and the design mechanisms. The design mechanism is the representation of the component behavior and performance in design and analysis tools. The focus in the early design process shifts from the development and
MEASUREMENT AND PRECISION, EXPERIMENTAL VERSION.
Harvard Univ., Cambridge, MA. Harvard Project Physics.
THIS DOCUMENT IS AN EXPERIMENTAL VERSION OF A PROGRAMED TEXT ON MEASUREMENT AND PRECISION. PART I CONTAINS 24 FRAMES DEALING WITH PRECISION AND SIGNIFICANT FIGURES ENCOUNTERED IN VARIOUS MATHEMATICAL COMPUTATIONS AND MEASUREMENTS. PART II BEGINS WITH A BRIEF SECTION ON EXPERIMENTAL DATA, COVERING SUCH POINTS AS (1) ESTABLISHING THE ZERO POINT, (2)…
Jacob, Joseph; Katz, Daniel; Prince, Thomas; Berriman, Graham; Good, John; Laity, Anastasia
2006-01-01
The final version (3.0) of the Montage software has been released. To recapitulate from previous NASA Tech Briefs articles about Montage: This software generates custom, science-grade mosaics of astronomical images on demand from input files that comply with the Flexible Image Transport System (FITS) standard and contain image data registered on projections that comply with the World Coordinate System (WCS) standards. This software can be executed on single-processor computers, multi-processor computers, and such networks of geographically dispersed computers as the National Science Foundation s TeraGrid or NASA s Information Power Grid. The primary advantage of running Montage in a grid environment is that computations can be done on a remote supercomputer for efficiency. Multiple computers at different sites can be used for different parts of a computation a significant advantage in cases of computations for large mosaics that demand more processor time than is available at any one site. Version 3.0 incorporates several improvements over prior versions. The most significant improvement is that this version is accessible to scientists located anywhere, through operational Web services that provide access to data from several large astronomical surveys and construct mosaics on either local workstations or remote computational grids as needed.
2010-01-01
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Communication and navigation equipment for... § 121.349 Communication and navigation equipment for operations under VFR over routes not navigated by... receiver providing visual and aural signals; and (iii) One ILS receiver; and (3) Any RNAV system used to...
Linear ubiquitination in immunity.
Shimizu, Yutaka; Taraborrelli, Lucia; Walczak, Henning
2015-07-01
Linear ubiquitination is a post-translational protein modification recently discovered to be crucial for innate and adaptive immune signaling. The function of linear ubiquitin chains is regulated at multiple levels: generation, recognition, and removal. These chains are generated by the linear ubiquitin chain assembly complex (LUBAC), the only known ubiquitin E3 capable of forming the linear ubiquitin linkage de novo. LUBAC is not only relevant for activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) in various signaling pathways, but importantly, it also regulates cell death downstream of immune receptors capable of inducing this response. Recognition of the linear ubiquitin linkage is specifically mediated by certain ubiquitin receptors, which is crucial for translation into the intended signaling outputs. LUBAC deficiency results in attenuated gene activation and increased cell death, causing pathologic conditions in both, mice, and humans. Removal of ubiquitin chains is mediated by deubiquitinases (DUBs). Two of them, OTULIN and CYLD, are constitutively associated with LUBAC. Here, we review the current knowledge on linear ubiquitination in immune signaling pathways and the biochemical mechanisms as to how linear polyubiquitin exerts its functions distinctly from those of other ubiquitin linkage types. © 2015 The Authors. Immunological Reviews Published by John Wiley & Sons Ltd.
33 CFR 209.170 - Violations of laws protecting navigable waters.
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Violations of laws protecting navigable waters. 209.170 Section 209.170 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF... navigable waters. (a) [Reserved] (b) Injuries to Government works. Section 14 of the River and Harbor Act of...
33 CFR 64.16 - Duration of marking on sunken vessels in navigable waters.
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Duration of marking on sunken vessels in navigable waters. 64.16 Section 64.16 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Sunken Vessels and Other Obstructions § 64.16 Duration of marking on sunken vessels in navigable waters...
33 CFR 117.458 - Inner Harbor Navigation Canal, New Orleans.
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inner Harbor Navigation Canal, New Orleans. 117.458 Section 117.458 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Harbor Navigation Canal, New Orleans. (a) The draws of the SR 46 (St. Claude Avenue) bridge, mile 0.5...
33 CFR 207.600 - Rochester (Charlotte) Harbor, N.Y.; use, administration, and navigation.
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Rochester (Charlotte) Harbor, N.Y.; use, administration, and navigation. 207.600 Section 207.600 Navigation and Navigable Waters CORPS OF... (Charlotte) Harbor, N.Y.; use, administration, and navigation. (a)-(b) [Reserved] (c) No vessel shall moor or...
33 CFR 207.580 - Buffalo Harbor, N.Y.; use, administration, and navigation.
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Buffalo Harbor, N.Y.; use, administration, and navigation. 207.580 Section 207.580 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.580 Buffalo Harbor, N.Y.; use...
Orion Optical Navigation Progress Toward Exploration Mission 1
Holt, Greg N.; D'Souza, Christopher N.; Saley, David
2018-01-01
Optical navigation of human spacecraft was proposed on Gemini and implemented successfully on Apollo as a means of autonomously operating the vehicle in the event of lost communication with controllers on Earth. The Orion emergency return system utilizing optical navigation has matured in design over the last several years, and is currently undergoing the final implementation and test phase in preparation for Exploration Mission 1 (EM-1) in 2019. The software development is past its Critical Design Review, and is progressing through test and certification for human rating. The filter architecture uses a square-root-free UDU covariance factorization. Linear Covariance Analysis (LinCov) was used to analyze the measurement models and the measurement error models on a representative EM-1 trajectory. The Orion EM-1 flight camera was calibrated at the Johnson Space Center (JSC) electro-optics lab. To permanently stake the focal length of the camera a 500 mm focal length refractive collimator was used. Two Engineering Design Unit (EDU) cameras and an EDU star tracker were used for a live-sky test in Denver. In-space imagery with high-fidelity truth metadata is rare so these live-sky tests provide one of the closest real-world analogs to operational use. A hardware-in-the-loop test rig was developed in the Johnson Space Center Electro-Optics Lab to exercise the OpNav system prior to integrated testing on the Orion vehicle. The software is verified with synthetic images. Several hundred off-nominal images are also used to analyze robustness and fault detection in the software. These include effects such as stray light, excess radiation damage, and specular reflections, and are used to help verify the tuning parameters chosen for the algorithms such as earth atmosphere bias, minimum pixel intensity, and star detection thresholds.
Optical surgical navigation system causes pulse oximeter malfunction.
Satoh, Masaaki; Hara, Tetsuhito; Tamai, Kenji; Shiba, Juntaro; Hotta, Kunihisa; Takeuchi, Mamoru; Watanabe, Eiju
2015-01-01
An optical surgical navigation system is used as a navigator to facilitate surgical approaches, and pulse oximeters provide valuable information for anesthetic management. However, saw-tooth waves on the monitor of a pulse oximeter and the inability of the pulse oximeter to accurately record the saturation of a percutaneous artery were observed when a surgeon started an optical navigation system. The current case is thought to be the first report of this navigation system interfering with pulse oximetry. The causes of pulse jamming and how to manage an optical navigation system are discussed.
Schneider, Hans
1989-01-01
Linear algebra is one of the central disciplines in mathematics. A student of pure mathematics must know linear algebra if he is to continue with modern algebra or functional analysis. Much of the mathematics now taught to engineers and physicists requires it.This well-known and highly regarded text makes the subject accessible to undergraduates with little mathematical experience. Written mainly for students in physics, engineering, economics, and other fields outside mathematics, the book gives the theory of matrices and applications to systems of linear equations, as well as many related t
Linearity in Process Languages
Nygaard, Mikkel; Winskel, Glynn
2002-01-01
The meaning and mathematical consequences of linearity (managing without a presumed ability to copy) are studied for a path-based model of processes which is also a model of affine-linear logic. This connection yields an affine-linear language for processes, automatically respecting open......-map bisimulation, in which a range of process operations can be expressed. An operational semantics is provided for the tensor fragment of the language. Different ways to make assemblies of processes lead to different choices of exponential, some of which respect bisimulation....
Amir-Moez, A R; Sneddon, I N
1962-01-01
Elements of Linear Space is a detailed treatment of the elements of linear spaces, including real spaces with no more than three dimensions and complex n-dimensional spaces. The geometry of conic sections and quadric surfaces is considered, along with algebraic structures, especially vector spaces and transformations. Problems drawn from various branches of geometry are given.Comprised of 12 chapters, this volume begins with an introduction to real Euclidean space, followed by a discussion on linear transformations and matrices. The addition and multiplication of transformations and matrices a
Weisberg, Sanford
2013-01-01
Praise for the Third Edition ""...this is an excellent book which could easily be used as a course text...""-International Statistical Institute The Fourth Edition of Applied Linear Regression provides a thorough update of the basic theory and methodology of linear regression modeling. Demonstrating the practical applications of linear regression analysis techniques, the Fourth Edition uses interesting, real-world exercises and examples. Stressing central concepts such as model building, understanding parameters, assessing fit and reliability, and drawing conclusions, the new edition illus
Low Cost Integrated Navigation System for Unmanned Vessel
Yang Changsong
2017-11-01
Full Text Available Large errors of low-cost MEMS inertial measurement unit (MIMU lead to huge navigation errors, even wrong navigation information. An integrated navigation system for unmanned vessel is proposed. It consists of a low-cost MIMU and Doppler velocity sonar (DVS. This paper presents an integrated navigation method, to improve the performance of navigation system. The integrated navigation system is tested using simulation and semi-physical simulation experiments, whose results show that attitude, velocity and position accuracy has improved awfully, giving exactly accurate navigation results. By means of the combination of low-cost MIMU and DVS, the proposed system is able to overcome fast drift problems of the low cost IMU.
Design of all-weather celestial navigation system
Sun, Hongchi; Mu, Rongjun; Du, Huajun; Wu, Peng
2018-03-01
In order to realize autonomous navigation in the atmosphere, an all-weather celestial navigation system is designed. The research of celestial navigation system include discrimination method of comentropy and the adaptive navigation algorithm based on the P value. The discrimination method of comentropy is studied to realize the independent switching of two celestial navigation modes, starlight and radio. Finally, an adaptive filtering algorithm based on P value is proposed, which can greatly improve the disturbance rejection capability of the system. The experimental results show that the accuracy of the three axis attitude is better than 10″, and it can work all weather. In perturbation environment, the position accuracy of the integrated navigation system can be increased 20% comparing with the traditional method. It basically meets the requirements of the all-weather celestial navigation system, and it has the ability of stability, reliability, high accuracy and strong anti-interference.
Dynamical structure of linearized GL(4) gravities
Aragone, C.; Restuccia, A.
1978-01-01
The physical content of the three more natural models of GL(4) gravity is analyzed, for the case of weak fields. It is shown that the first model is the linearized version of Yang's one-tensor-field gravity and is a scalar-tensor theory, with its scalar part contained in a symmetric tensor. The second and the third linearized models, which can both be derived from the fourth-order action postulated by Yang, are two-tensor decoupled systems. In both cases one of the tensors is the symmetric weak metric gravity tensor field. the second tensor appearing in these two models, representing the GL(4)-gauge field, is either a linearized symmetric affinity (in the second model) or a linearized but nonsymmetric affinity (for the third model). It is shown that in these last two cases the affinity contains a helicity-3 propagating field. Owing to the presence of helicity-3 fields it is shown that it is better to regard Yang's action as an action for a two-tensor system instead of trying to recover from a pure gravity (one-tensor-field) action. Finally, it is shown what is the dynamical structure of the second and third linearized two-tensor models which can be derived from Yang's action. (author)
Testing Two Tools for Multimodal Navigation
Mats Liljedahl
2012-01-01
Full Text Available The latest smartphones with GPS, electronic compasses, directional audio, touch screens, and so forth, hold a potential for location-based services that are easier to use and that let users focus on their activities and the environment around them. Rather than interpreting maps, users can search for information by pointing in a direction and database queries can be created from GPS location and compass data. Users can also get guidance to locations through point and sweep gestures, spatial sound, and simple graphics. This paper describes two studies testing two applications with multimodal user interfaces for navigation and information retrieval. The applications allow users to search for information and get navigation support using combinations of point and sweep gestures, nonspeech audio, graphics, and text. Tests show that users appreciated both applications for their ease of use and for allowing users to interact directly with the surrounding environment.
Visual Navigation of Complex Information Spaces
Sarah North
1995-11-01
Full Text Available The authors lay the foundation for the introduction of visual navigation aid to assist computer users in direct manipulation of the complex information spaces. By exploring present research on scientific data visualisation and creating a case for improved information visualisation tools, they introduce the design of an improved information visualisation interface utilizing dynamic slider, called Visual-X, incorporating icons with bindable attributes (glyphs. Exploring the improvement that these data visualisations, make to a computing environment, the authors conduct an experiment to compare the performance of subjects who use traditional interfaces and Visual-X. Methodology is presented and conclusions reveal that the use of Visual-X appears to be a promising approach in providing users with a navigation tool that does not overload their cognitive processes.
Unraveling navigational strategies in migratory insects.
Merlin, Christine; Heinze, Stanley; Reppert, Steven M
2012-04-01
Long-distance migration is a strategy some animals use to survive a seasonally changing environment. To reach favorable grounds, migratory animals have evolved sophisticated navigational mechanisms that rely on a map and compasses. In migratory insects, the existence of a map sense (sense of position) remains poorly understood, but recent work has provided new insights into the mechanisms some compasses use for maintaining a constant bearing during long-distance navigation. The best-studied directional strategy relies on a time-compensated sun compass, used by diurnal insects, for which neural circuits have begun to be delineated. Yet, a growing body of evidence suggests that migratory insects may also rely on other compasses that use night sky cues or the Earth's magnetic field. Those mechanisms are ripe for exploration. Copyright © 2011 Elsevier Ltd. All rights reserved.
Automatic document navigation for digital content remastering
Lin, Xiaofan; Simske, Steven J.
2003-12-01
This paper presents a novel method of automatically adding navigation capabilities to re-mastered electronic books. We first analyze the need for a generic and robust system to automatically construct navigation links into re-mastered books. We then introduce the core algorithm based on text matching for building the links. The proposed method utilizes the tree-structured dictionary and directional graph of the table of contents to efficiently conduct the text matching. Information fusion further increases the robustness of the algorithm. The experimental results on the MIT Press digital library project are discussed and the key functional features of the system are illustrated. We have also investigated how the quality of the OCR engine affects the linking algorithm. In addition, the analogy between this work and Web link mining has been pointed out.
Effects of age on navigation strategy.
Rodgers, M Kirk; Sindone, Joseph A; Moffat, Scott D
2012-01-01
Age differences in navigation strategies have been demonstrated in animals, with aged animals more likely to prefer an egocentric (route) strategy and younger animals more likely to prefer an allocentric (place) strategy. Using a novel virtual Y-maze strategy assessment (vYSA), the present study demonstrated substantial age differences in strategy preference in humans. Older adults overwhelmingly preferred an egocentric strategy, while younger adults were equally distributed between egocentric and allocentric preference. A preference for allocentric strategy on the Y-maze strategy assessment was found to benefit performance on an independent assessment (virtual Morris water task) only in younger adults. These results establish baseline age differences in spatial strategies and suggest this may impact performance on other spatial navigation assessments. The results are interpreted within the framework of age differences in hippocampal structure and function. Copyright © 2012 Elsevier Inc. All rights reserved.
Navigation simulator for the Space Tug vehicle
Colburn, B. K.; Boland, J. S., III; Peters, E. G.
1977-01-01
A general simulation program (GSP) for state estimation of a nonlinear space vehicle flight navigation system is developed and used as a basis for evaluating the performance of a Space Tug navigation system. An explanation of the iterative guidance mode (IGM) guidance law, derivation of the dynamics, coordinate frames and state estimation routines are given in order to clarify the assumptions and approximations made. A number of simulation and analytical studies are used to demonstrate the operation of the Tug system. Included in the simulation studies are (1) initial offset vector parameter study; (2) propagation time vs accuracy; (3) measurement noise parametric study and (4) reduction in computational burden of an on-board implementable scheme. From the results of these studies, conclusions and recommendations concerning future areas of practical and theoretical work are presented.
Intrinsic Grassmann Averages for Online Linear and Robust Subspace Learning
Chakraborty, Rudrasis; Hauberg, Søren; Vemuri, Baba C.
2017-01-01
Principal Component Analysis (PCA) is a fundamental method for estimating a linear subspace approximation to high-dimensional data. Many algorithms exist in literature to achieve a statistically robust version of PCA called RPCA. In this paper, we present a geometric framework for computing the p...
Internet-Based Indoor Navigation Services
Zeinalipour-Yazti, Demetrios; Laoudias, Christos; Georgiou, Kyriakos
2017-01-01
Smartphone advances are leading to a class of Internet-based Indoor Navigation services. IIN services rely on geolocation databases that store indoor models, comprising floor maps and points of interest, along with wireless, light, and magnetic signals for localizing users. Developing IIN services creates new information management challenges - such as crowdsourcing indoor models, acquiring and fusing big data velocity signals, localization algorithms, and custodians' location privacy. Here, ...
Towards automated visual flexible endoscope navigation.
van der Stap, Nanda; van der Heijden, Ferdinand; Broeders, Ivo A M J
2013-10-01
The design of flexible endoscopes has not changed significantly in the past 50 years. A trend is observed towards a wider application of flexible endoscopes with an increasing role in complex intraluminal therapeutic procedures. The nonintuitive and nonergonomical steering mechanism now forms a barrier in the extension of flexible endoscope applications. Automating the navigation of endoscopes could be a solution for this problem. This paper summarizes the current state of the art in image-based navigation algorithms. The objectives are to find the most promising navigation system(s) to date and to indicate fields for further research. A systematic literature search was performed using three general search terms in two medical-technological literature databases. Papers were included according to the inclusion criteria. A total of 135 papers were analyzed. Ultimately, 26 were included. Navigation often is based on visual information, which means steering the endoscope using the images that the endoscope produces. Two main techniques are described: lumen centralization and visual odometry. Although the research results are promising, no successful, commercially available automated flexible endoscopy system exists to date. Automated systems that employ conventional flexible endoscopes show the most promising prospects in terms of cost and applicability. To produce such a system, the research focus should lie on finding low-cost mechatronics and technologically robust steering algorithms. Additional functionality and increased efficiency can be obtained through software development. The first priority is to find real-time, robust steering algorithms. These algorithms need to handle bubbles, motion blur, and other image artifacts without disrupting the steering process.
Spatial navigation by congenitally blind individuals
Schinazi, Victor R.; Thrash, Tyler; Chebat, Daniel?Robert
2015-01-01
Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergen...
Solar-based navigation for robotic explorers
Shillcutt, Kimberly Jo
2000-12-01
This thesis introduces the application of solar position and shadowing information to robotic exploration. Power is a critical resource for robots with remote, long-term missions, so this research focuses on the power generation capabilities of robotic explorers during navigational tasks, in addition to power consumption. Solar power is primarily considered, with the possibility of wind power also contemplated. Information about the environment, including the solar ephemeris, terrain features, time of day, and surface location, is incorporated into a planning structure, allowing robots to accurately predict shadowing and thus potential costs and gains during navigational tasks. By evaluating its potential to generate and expend power, a robot can extend its lifetime and accomplishments. The primary tasks studied are coverage patterns, with a variety of plans developed for this research. The use of sun, terrain and temporal information also enables new capabilities of identifying and following sun-synchronous and sun-seeking paths. Digital elevation maps are combined with an ephemeris algorithm to calculate the altitude and azimuth of the sun from surface locations, and to identify and map shadows. Solar navigation path simulators use this information to perform searches through two-dimensional space, while considering temporal changes. Step by step simulations of coverage patterns also incorporate time in addition to location. Evaluations of solar and wind power generation, power consumption, area coverage, area overlap, and time are generated for sets of coverage patterns, with on-board environmental information linked to the simulations. This research is implemented on the Nomad robot for the Robotic Antarctic Meteorite Search. Simulators have been developed for coverage pattern tests, as well as for sun-synchronous and sun-seeking path searches. Results of field work and simulations are reported and analyzed, with demonstrated improvements in efficiency
Callier, Frank M.; Desoer, Charles A.
1991-01-01
The aim of this book is to provide a systematic and rigorous access to the main topics of linear state-space system theory in both the continuous-time case and the discrete-time case; and the I/O description of linear systems. The main thrusts of the work are the analysis of system descriptions and derivations of their properties, LQ-optimal control, state feedback and state estimation, and MIMO unity-feedback systems.
Vectorization of linear discrete filtering algorithms
Schiess, J. R.
1977-01-01
Linear filters, including the conventional Kalman filter and versions of square root filters devised by Potter and Carlson, are studied for potential application on streaming computers. The square root filters are known to maintain a positive definite covariance matrix in cases in which the Kalman filter diverges due to ill-conditioning of the matrix. Vectorization of the filters is discussed, and comparisons are made of the number of operations and storage locations required by each filter. The Carlson filter is shown to be the most efficient of the filters on the Control Data STAR-100 computer.
Decoding Algorithms for Random Linear Network Codes
Heide, Janus; Pedersen, Morten Videbæk; Fitzek, Frank
2011-01-01
We consider the problem of efficient decoding of a random linear code over a finite field. In particular we are interested in the case where the code is random, relatively sparse, and use the binary finite field as an example. The goal is to decode the data using fewer operations to potentially...... achieve a high coding throughput, and reduce energy consumption.We use an on-the-fly version of the Gauss-Jordan algorithm as a baseline, and provide several simple improvements to reduce the number of operations needed to perform decoding. Our tests show that the improvements can reduce the number...
Basic linear algebra subprograms for FORTRAN usage
Lawson, C. L.; Hanson, R. J.; Kincaid, D. R.; Krogh, F. T.
1977-01-01
A package of 38 low level subprograms for many of the basic operations of numerical linear algebra is presented. The package is intended to be used with FORTRAN. The operations in the package are dot products, elementary vector operations, Givens transformations, vector copy and swap, vector norms, vector scaling, and the indices of components of largest magnitude. The subprograms and a test driver are available in portable FORTRAN. Versions of the subprograms are also provided in assembly language for the IBM 360/67, the CDC 6600 and CDC 7600, and the Univac 1108.
Celestial Navigation in the USA, Fiji, and Tunisia
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.
DVL Velocity Aiding in the HUGIN 1000 Integrated Inertial Navigation System
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.
Two-dimensional small-world networks: Navigation with local information
Chen Jianzhen; Liu Wei; Zhu Jianyang
2006-01-01
A navigation process is studied on a variant of the Watts-Strogatz small-world network model embedded on a square lattice. With probability p, each vertex sends out a long-range link, and the probability of the other end of this link falling on a vertex at lattice distance r away decays as r -α . Vertices on the network have knowledge of only their nearest neighbors. In a navigation process, messages are forwarded to a designated target. For α 1, a dynamic small world effect is observed, and the behavior of the scaling function at large enough pL is obtained. At α=2 and 3, this kind of scaling breaks down, and different functions of the average actual path length are obtained. For α>3, the average actual path length is nearly linear with network size
Prefrontal-hippocampal interactions for spatial navigation.
Ito, Hiroshi T
2018-04-01
Animals have the ability to navigate to a desired location by making use of information about environmental landmarks and their own movements. While decades of neuroscience research have identified neurons in the hippocampus and parahippocampal structures that represent an animal's position in space, it is still largely unclear how an animal can choose the next movement direction to reach a desired goal. As the goal destination is typically located somewhere outside of the range of sensory perception, the animal is required to rely on the internal metric of space to estimate the direction and distance of the destination to plan a next action. Therefore, the hippocampal spatial map should interact with action-planning systems in other cortical regions. In accordance with this idea, several recent studies have indicated the importance of functional interactions between the hippocampus and the prefrontal cortex for goal-directed navigation. In this paper, I will review these studies and discuss how an animal can estimate its future positions correspond to a next movement. Investigation of the navigation problem may further provide general insights into internal models of the brain for action planning. Copyright © 2017 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.
Laboratory experiments in mobile robot navigation
Kar, Asim; Pal, Prabir K.
1997-01-01
Mobile robots have potential applications in remote surveillance and operation in hazardous areas. To be effective, they must have the ability to navigate on their own to desired locations. Several experimental navigational runs of a mobile robot developed have been conducted. The robot has three wheels of which the front wheel is steered and the hind wheels are driven. The robot is equipped with an ultrasonic range sensor, which is turned around to get range data in all directions. The range data is fed to the input of a neural net, whose output steers the robot towards the goal. The robot is powered by batteries (12V 10Ah). It has an onboard stepper motor controller for driving the wheels and the ultrasonic setup. It also has an onboard computer which runs the navigation program NAV. This program sends the range data and configuration parameters to the operator''s console program OCP, running on a stationary PC, through radio communication on a serial line. Through OCP, an operator can monitor the progress of the robot from a distant control room and intervene if necessary. In this paper the control modules of the mobile robot, its ways of operation and also results of some of the experimental runs recorded are reported. It is seen that the trained net guides the mobile robot through gaps of 1m and above to its destination with about 84% success measured over a small sample of 38 runs
Geomagnetic storm effects on GPS based navigation
P. V. S. Rama Rao
2009-05-01
Full Text Available The energetic events on the sun, solar wind and subsequent effects on the Earth's geomagnetic field and upper atmosphere (ionosphere comprise space weather. Modern navigation systems that use radio-wave signals, reflecting from or propagating through the ionosphere as a means of determining range or distance, are vulnerable to a variety of effects that can degrade the performance of the navigational systems. In particular, the Global Positioning System (GPS that uses a constellation of earth orbiting satellites are affected due to the space weather phenomena.
Studies made during two successive geomagnetic storms that occurred during the period from 8 to 12 November 2004, have clearly revealed the adverse affects on the GPS range delay as inferred from the Total Electron Content (TEC measurements made from a chain of seven dual frequency GPS receivers installed in the Indian sector. Significant increases in TEC at the Equatorial Ionization anomaly crest region are observed, resulting in increased range delay during the periods of the storm activity. Further, the storm time rapid changes occurring in TEC resulted in a number of phase slips in the GPS signal compared to those on quiet days. These phase slips often result in the loss of lock of the GPS receivers, similar to those that occur during strong(>10 dB L-band scintillation events, adversely affecting the GPS based navigation.
Velocity navigator for motion compensated thermometry.
Maier, Florian; Krafft, Axel J; Yung, Joshua P; Stafford, R Jason; Elliott, Andrew; Dillmann, Rüdiger; Semmler, Wolfhard; Bock, Michael
2012-02-01
Proton resonance frequency shift thermometry is sensitive to breathing motion that leads to incorrect phase differences. In this work, a novel velocity-sensitive navigator technique for triggering MR thermometry image acquisition is presented. A segmented echo planar imaging pulse sequence was modified for velocity-triggered temperature mapping. Trigger events were generated when the estimated velocity value was less than 0.2 cm/s during the slowdown phase in parallel to the velocity-encoding direction. To remove remaining high-frequency spikes from pulsation in real time, a Kalman filter was applied to the velocity navigator data. A phantom experiment with heating and an initial volunteer experiment without heating were performed to show the applicability of this technique. Additionally, a breath-hold experiment was conducted for comparison. A temperature rise of ΔT = +37.3°C was seen in the phantom experiment, and a root mean square error (RMSE) outside the heated region of 2.3°C could be obtained for periodic motion. In the volunteer experiment, a RMSE of 2.7°C/2.9°C (triggered vs. breath hold) was measured. A novel velocity navigator with Kalman filter postprocessing in real time significantly improves the temperature accuracy over non-triggered acquisitions and suggests being comparable to a breath-held acquisition. The proposed technique might be clinically applied for monitoring of thermal ablations in abdominal organs.
Modelling female fertility traits in beef cattle using linear and non-linear models.
Naya, H; Peñagaricano, F; Urioste, J I
2017-06-01
Female fertility traits are key components of the profitability of beef cattle production. However, these traits are difficult and expensive to measure, particularly under extensive pastoral conditions, and consequently, fertility records are in general scarce and somehow incomplete. Moreover, fertility traits are usually dominated by the effects of herd-year environment, and it is generally assumed that relatively small margins are kept for genetic improvement. New ways of modelling genetic variation in these traits are needed. Inspired in the methodological developments made by Prof. Daniel Gianola and co-workers, we assayed linear (Gaussian), Poisson, probit (threshold), censored Poisson and censored Gaussian models to three different kinds of endpoints, namely calving success (CS), number of days from first calving (CD) and number of failed oestrus (FE). For models involving FE and CS, non-linear models overperformed their linear counterparts. For models derived from CD, linear versions displayed better adjustment than the non-linear counterparts. Non-linear models showed consistently higher estimates of heritability and repeatability in all cases (h 2 linear models; h 2 > 0.23 and r > 0.24, for non-linear models). While additive and permanent environment effects showed highly favourable correlations between all models (>0.789), consistency in selecting the 10% best sires showed important differences, mainly amongst the considered endpoints (FE, CS and CD). In consequence, endpoints should be considered as modelling different underlying genetic effects, with linear models more appropriate to describe CD and non-linear models better for FE and CS. © 2017 Blackwell Verlag GmbH.
Navigation and Image Injection for Control of Bone Removal and Osteotomy Planes in Spine Surgery.
Kosterhon, Michael; Gutenberg, Angelika; Kantelhardt, Sven Rainer; Archavlis, Elefterios; Giese, Alf
2017-04-01
In contrast to cranial interventions, neuronavigation in spinal surgery is used in few applications, not tapping into its full technological potential. We have developed a method to preoperatively create virtual resection planes and volumes for spinal osteotomies and export 3-D operation plans to a navigation system controlling intraoperative visualization using a surgical microscope's head-up display. The method was developed using a Sawbone ® model of the lumbar spine, demonstrating feasibility with high precision. Computer tomographic and magnetic resonance image data were imported into Amira ® , a 3-D visualization software. Resection planes were positioned, and resection volumes representing intraoperative bone removal were defined. Fused to the original Digital Imaging and Communications in Medicine data, the osteotomy planes were exported to the cranial version of a Brainlab ® navigation system. A navigated surgical microscope with video connection to the navigation system allowed intraoperative image injection to visualize the preplanned resection planes. The workflow was applied to a patient presenting with a congenital hemivertebra of the thoracolumbar spine. Dorsal instrumentation with pedicle screws and rods was followed by resection of the deformed vertebra guided by the in-view image injection of the preplanned resection planes into the optical path of a surgical microscope. Postoperatively, the patient showed no neurological deficits, and the spine was found to be restored in near physiological posture. The intraoperative visualization of resection planes in a microscope's head-up display was found to assist the surgeon during the resection of a complex-shaped bone wedge and may help to further increase accuracy and patient safety. Copyright © 2017 by the Congress of Neurological Surgeons
National Oceanic and Atmospheric Administration, Department of Commerce — Version 2 of the dataset has been superseded by a newer version. Users should not use version 2 except in rare cases (e.g., when reproducing previous studies that...
National Oceanic and Atmospheric Administration, Department of Commerce — Version 1 of the dataset has been superseded by a newer version. Users should not use version 1 except in rare cases (e.g., when reproducing previous studies that...
Larin, S.A.; Academy of Sciences of the USSR, Moscow; Tkachov, F.V.; McGill Univ., Montreal, PQ; Academy of Sciences of the USSR, Moscow; Vermaseren, J.A.M.
1991-01-01
The program MINCER for massless three-loop Feynman diagrams of the propagator type has been reprogrammed in the language of FORM. The new version is thoroughly optimized and can be run from a utility like the UNIX make, which allows one to conveniently process large numbers of diagrams. It has been used for some calculations that were previously not practical. (author). 22 refs.; 14 figs
Krueger, Samantha; Simioni, Julia; Griffith, Lauren E; Hutton, Eileen K
2018-01-01
This study sought to compare obstetrical outcomes for women with a cephalic presentation at birth resulting from successful external cephalic version (ECV) compared to those resulting from spontaneous cephalic version (SCV). Secondary analysis was performed on Early External Cephalic Version Trial data. A total of 931 study participants had breech presentations between 34 and 36 weeks' gestation and cephalic presentations at birth. The incidence of intrapartum interventions was compared between patients with successful ECV (557) and those with SCV (374). A generalized linear mixed model was used to determine ORs for our primary outcomes. Parity, maternal BMI, previous CS, and enrolment centre were controlled for in the analysis. No differences were found after ECV compared with SCV in the incidence of CS (96 of 557 and 76 of 374, respectively; adjusted OR [aOR] 0.89; 95% CI 0.63-1.26), instrumental birth (68 of 557 and 29 of 373, respectively; aOR 1.55; 95% CI 0.96-2.50), or normal vaginal birth (393 of 557 and 268 of 373, respectively; aOR 0.92; 95% CI 0.68-1.24). Multiparous women with successful ECV were half as likely to require a CS compared with those with SCV and no ECV (28 of 313 and 42 of 258, respectively; aOR 0.45; 95% CI 0.26-0.80). This is the first study to compare birth outcomes of breech pregnancies that convert to cephalic presentation by means of SCV with birth outcomes of breech pregnancies that have ECV. Women with a cephalic-presenting fetus at birth as a result of successful ECV are not at greater risk of obstetrical interventions at birth when compared with women with fetuses who spontaneously turn to a cephalic presentation in the third trimester. Copyright © 2018. Published by Elsevier Inc.
Blyth, T S
2002-01-01
Most of the introductory courses on linear algebra develop the basic theory of finite dimensional vector spaces, and in so doing relate the notion of a linear mapping to that of a matrix. Generally speaking, such courses culminate in the diagonalisation of certain matrices and the application of this process to various situations. Such is the case, for example, in our previous SUMS volume Basic Linear Algebra. The present text is a continuation of that volume, and has the objective of introducing the reader to more advanced properties of vector spaces and linear mappings, and consequently of matrices. For readers who are not familiar with the contents of Basic Linear Algebra we provide an introductory chapter that consists of a compact summary of the prerequisites for the present volume. In order to consolidate the student's understanding we have included a large num ber of illustrative and worked examples, as well as many exercises that are strategi cally placed throughout the text. Solutions to the ex...
Kuipers, J.; Ueda, T.; Vermaseren, J. A. M.; Vollinga, J.
2013-05-01
We present version 4.0 of the symbolic manipulation system FORM. The most important new features are manipulation of rational polynomials and the factorization of expressions. Many other new functions and commands are also added; some of them are very general, while others are designed for building specific high level packages, such as one for Gröbner bases. New is also the checkpoint facility, that allows for periodic backups during long calculations. Finally, FORM 4.0 has become available as open source under the GNU General Public License version 3. Program summaryProgram title: FORM. Catalogue identifier: AEOT_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOT_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 151599 No. of bytes in distributed program, including test data, etc.: 1 078 748 Distribution format: tar.gz Programming language: The FORM language. FORM itself is programmed in a mixture of C and C++. Computer: All. Operating system: UNIX, LINUX, Mac OS, Windows. Classification: 5. Nature of problem: FORM defines a symbolic manipulation language in which the emphasis lies on fast processing of very large formulas. It has been used successfully for many calculations in Quantum Field Theory and mathematics. In speed and size of formulas that can be handled it outperforms other systems typically by an order of magnitude. Special in this version: The version 4.0 contains many new features. Most important are factorization and rational arithmetic. The program has also become open source under the GPL. The code in CPC is for reference. You are encouraged to upload the most recent sources from www.nikhef.nl/form/formcvs.php because of frequent bug fixes. Solution method: See "Nature of Problem", above. Additional comments: NOTE: The code in CPC is for reference. You are encouraged
Park, Young W.; Montez, Moises N.
1994-01-01
A candidate onboard space navigation filter demonstrated excellent performance (less than 8 meter level RMS semi-major axis accuracy) in performing orbit determination of a low-Earth orbit Explorer satellite using single-frequency real GPS data. This performance is significantly better than predicted by other simulation studies using dual-frequency GPS data. The study results revealed the significance of two new modeling approaches evaluated in the work. One approach introduces a single-frequency ionospheric correction through pseudo-range and phase range averaging implementation. The other approach demonstrates a precise axis-dependent characterization of dynamic sample space uncertainty to compute a more accurate Kalman filter gain. Additionally, this navigation filter demonstrates a flexibility to accommodate both perturbational dynamic and observational biases required for multi-flight phase and inhomogeneous application environments. This paper reviews the potential application of these methods and the filter structure to terrestrial vehicle and positioning applications. Both the single-frequency ionospheric correction method and the axis-dependent state noise modeling approach offer valuable contributions in cost and accuracy improvements for terrestrial GPS receivers. With a modular design approach to either 'plug-in' or 'unplug' various force models, this multi-flight phase navigation filter design structure also provides a versatile GPS navigation software engine for both atmospheric and exo-atmospheric navigation or positioning use, thereby streamlining the flight phase or application-dependent software requirements. Thus, a standardized GPS navigation software engine that can reduce the development and maintenance cost of commercial GPS receivers is now possible.
An Online Solution of LiDAR Scan Matching Aided Inertial Navigation System for Indoor Mobile Mapping
Xiaoji Niu
2017-01-01
Full Text Available Multisensors (LiDAR/IMU/CAMERA integrated Simultaneous Location and Mapping (SLAM technology for navigation and mobile mapping in a GNSS-denied environment, such as indoor areas, dense forests, or urban canyons, becomes a promising solution. An online (real-time version of such system can extremely extend its applications, especially for indoor mobile mapping. However, the real-time response issue of multisensors is a big challenge for an online SLAM system, due to the different sampling frequencies and processing time of different algorithms. In this paper, an online Extended Kalman Filter (EKF integrated algorithm of LiDAR scan matching and IMU mechanization for Unmanned Ground Vehicle (UGV indoor navigation system is introduced. Since LiDAR scan matching is considerably more time consuming than the IMU mechanism, the real-time synchronous issue is solved via a one-step-error-state-transition method in EKF. Stationary and dynamic field tests had been performed using a UGV platform along typical corridor of office building. Compared to the traditional sequential postprocessed EKF algorithm, the proposed method can significantly mitigate the time delay of navigation outputs under the premise of guaranteeing the positioning accuracy, which can be used as an online navigation solution for indoor mobile mapping.
Project Management Using Modern Guidance, Navigation and Control Theory
Hill, Terry
2010-01-01
The idea of control theory and its application to project management is not new, however literature on the topic and real-world applications is not as readily available and comprehensive in how all the principals of Guidance, Navigation and Control (GN&C) apply. This paper will address how the fundamental principals of modern GN&C Theory have been applied to NASA's Constellation Space Suit project and the results in the ability to manage the project within cost, schedule and budget. A s with physical systems, projects can be modeled and managed with the same guiding principles of GN&C as if it were a complex vehicle, system or software with time-varying processes, at times non-linear responses, multiple data inputs of varying accuracy and a range of operating points. With such systems the classic approach could be applied to small and well-defined projects; however with larger, multi-year projects involving multiple organizational structures, external influences and a multitude of diverse resources, then modern control theory is required to model and control the project. The fundamental principals of G N&C stated that a system is comprised of these basic core concepts: State, Behavior, Control system, Navigation system, Guidance and Planning Logic, Feedback systems. The state of a system is a definition of the aspects of the dynamics of the system that can change, such as position, velocity, acceleration, coordinate-based attitude, temperature, etc. The behavior of the system is more of what changes are possible rather than what can change, which is captured in the state of the system. The behavior of a system is captured in the system modeling and if properly done, will aid in accurate system performance prediction in the future. The Control system understands the state and behavior of the system and feedback systems to adjust the control inputs into the system. The Navigation system takes the multiple data inputs and based upon a priori knowledge of the input
Mamyrin, B.A.; Shmikk, D.V.
1979-01-01
A description and operating principle of a linear mass reflectron with V-form trajectory of ion motion -a new non-magnetic time-of-flight mass spectrometer with high resolution are presented. The ion-optical system of the device consists of an ion source with ionization by electron shock, of accelerating gaps, reflector gaps, a drift space and ion detector. Ions move in the linear mass refraction along the trajectories parallel to the axis of the analyzer chamber. The results of investigations into the experimental device are given. With an ion drift length of 0.6 m the device resolution is 1200 with respect to the peak width at half-height. Small-sized mass spectrometric transducers with high resolution and sensitivity may be designed on the base of the linear mass reflectron principle
Olver, Peter J
2018-01-01
This textbook develops the essential tools of linear algebra, with the goal of imparting technique alongside contextual understanding. Applications go hand-in-hand with theory, each reinforcing and explaining the other. This approach encourages students to develop not only the technical proficiency needed to go on to further study, but an appreciation for when, why, and how the tools of linear algebra can be used across modern applied mathematics. Providing an extensive treatment of essential topics such as Gaussian elimination, inner products and norms, and eigenvalues and singular values, this text can be used for an in-depth first course, or an application-driven second course in linear algebra. In this second edition, applications have been updated and expanded to include numerical methods, dynamical systems, data analysis, and signal processing, while the pedagogical flow of the core material has been improved. Throughout, the text emphasizes the conceptual connections between each application and the un...
Banach, S
1987-01-01
This classic work by the late Stefan Banach has been translated into English so as to reach a yet wider audience. It contains the basics of the algebra of operators, concentrating on the study of linear operators, which corresponds to that of the linear forms a1x1 + a2x2 + ... + anxn of algebra.The book gathers results concerning linear operators defined in general spaces of a certain kind, principally in Banach spaces, examples of which are: the space of continuous functions, that of the pth-power-summable functions, Hilbert space, etc. The general theorems are interpreted in various mathematical areas, such as group theory, differential equations, integral equations, equations with infinitely many unknowns, functions of a real variable, summation methods and orthogonal series.A new fifty-page section (``Some Aspects of the Present Theory of Banach Spaces'''') complements this important monograph.
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four of these cri......Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
Linear programming using Matlab
Ploskas, Nikolaos
2017-01-01
This book offers a theoretical and computational presentation of a variety of linear programming algorithms and methods with an emphasis on the revised simplex method and its components. A theoretical background and mathematical formulation is included for each algorithm as well as comprehensive numerical examples and corresponding MATLAB® code. The MATLAB® implementations presented in this book are sophisticated and allow users to find solutions to large-scale benchmark linear programs. Each algorithm is followed by a computational study on benchmark problems that analyze the computational behavior of the presented algorithms. As a solid companion to existing algorithmic-specific literature, this book will be useful to researchers, scientists, mathematical programmers, and students with a basic knowledge of linear algebra and calculus. The clear presentation enables the reader to understand and utilize all components of simplex-type methods, such as presolve techniques, scaling techniques, pivoting ru...
Anon.
1994-01-01
The aim of the TESLA (TeV Superconducting Linear Accelerator) collaboration (at present 19 institutions from seven countries) is to establish the technology for a high energy electron-positron linear collider using superconducting radiofrequency cavities to accelerate its beams. Another basic goal is to demonstrate that such a collider can meet its performance goals in a cost effective manner. For this the TESLA collaboration is preparing a 500 MeV superconducting linear test accelerator at the DESY Laboratory in Hamburg. This TTF (TESLA Test Facility) consists of four cryomodules, each approximately 12 m long and containing eight 9-cell solid niobium cavities operating at a frequency of 1.3 GHz
Versions of the Waste Reduction Model (WARM)
This page provides a brief chronology of changes made to EPA’s Waste Reduction Model (WARM), organized by WARM version number. The page includes brief summaries of changes and updates since the previous version.
Linearly Adjustable International Portfolios
Fonseca, R. J.; Kuhn, D.; Rustem, B.
2010-09-01
We present an approach to multi-stage international portfolio optimization based on the imposition of a linear structure on the recourse decisions. Multiperiod decision problems are traditionally formulated as stochastic programs. Scenario tree based solutions however can become intractable as the number of stages increases. By restricting the space of decision policies to linear rules, we obtain a conservative tractable approximation to the original problem. Local asset prices and foreign exchange rates are modelled separately, which allows for a direct measure of their impact on the final portfolio value.
Linearly Adjustable International Portfolios
Fonseca, R. J.; Kuhn, D.; Rustem, B.
2010-01-01
We present an approach to multi-stage international portfolio optimization based on the imposition of a linear structure on the recourse decisions. Multiperiod decision problems are traditionally formulated as stochastic programs. Scenario tree based solutions however can become intractable as the number of stages increases. By restricting the space of decision policies to linear rules, we obtain a conservative tractable approximation to the original problem. Local asset prices and foreign exchange rates are modelled separately, which allows for a direct measure of their impact on the final portfolio value.
Barkman, W.E.; Adams, W.Q.; Berrier, B.R.
1978-01-01
A linear induction motor has been operated on a test bed with a feedback pulse resolution of 5 nm (0.2 μin). Slewing tests with this slide drive have shown positioning errors less than or equal to 33 nm (1.3 μin) at feedrates between 0 and 25.4 mm/min (0-1 ipm). A 0.86-m (34-in)-stroke linear motor is being investigated, using the SPACO machine as a test bed. Initial results were encouraging, and work is continuing to optimize the servosystem compensation
Hogben, Leslie
2013-01-01
With a substantial amount of new material, the Handbook of Linear Algebra, Second Edition provides comprehensive coverage of linear algebra concepts, applications, and computational software packages in an easy-to-use format. It guides you from the very elementary aspects of the subject to the frontiers of current research. Along with revisions and updates throughout, the second edition of this bestseller includes 20 new chapters.New to the Second EditionSeparate chapters on Schur complements, additional types of canonical forms, tensors, matrix polynomials, matrix equations, special types of
Linear Algebra Thoroughly Explained
Vujičić, Milan
2008-01-01
Linear Algebra Thoroughly Explained provides a comprehensive introduction to the subject suitable for adoption as a self-contained text for courses at undergraduate and postgraduate level. The clear and comprehensive presentation of the basic theory is illustrated throughout with an abundance of worked examples. The book is written for teachers and students of linear algebra at all levels and across mathematics and the applied sciences, particularly physics and engineering. It will also be an invaluable addition to research libraries as a comprehensive resource book for the subject.
Moafipoor, Shahram
Personal navigators (PN) have been studied for about a decade in different fields and applications, such as safety and rescue operations, security and emergency services, and police and military applications. The common goal of all these applications is to provide precise and reliable position, velocity, and heading information of each individual in various environments. In the PN system developed in this dissertation, the underlying assumption is that the system does not require pre-existing infrastructure to enable pedestrian navigation. To facilitate this capability, a multisensor system concept, based on the Global Positioning System (GPS), inertial navigation, barometer, magnetometer, and a human pedometry model has been developed. An important aspect of this design is to use the human body as navigation sensor to facilitate Dead Reckoning (DR) navigation in GPS-challenged environments. The system is designed predominantly for outdoor environments, where occasional loss of GPS lock may happen; however, testing and performance demonstration have been extended to indoor environments. DR navigation is based on a relative-measurement approach, with the key idea of integrating the incremental motion information in the form of step direction (SD) and step length (SL) over time. The foundation of the intelligent navigation system concept proposed here rests in exploiting the human locomotion pattern, as well as change of locomotion in varying environments. In this context, the term intelligent navigation represents the transition from the conventional point-to-point DR to dynamic navigation using the knowledge about the mechanism of the moving person. This approach increasingly relies on integrating knowledge-based systems (KBS) and artificial intelligence (AI) methodologies, including artificial neural networks (ANN) and fuzzy logic (FL). In addition, a general framework of the quality control for the real-time validation of the DR processing is proposed, based on a
Kent, James; Holdaway, Daniel
2015-01-01
A number of geophysical applications require the use of the linearized version of the full model. One such example is in numerical weather prediction, where the tangent linear and adjoint versions of the atmospheric model are required for the 4DVAR inverse problem. The part of the model that represents the resolved scale processes of the atmosphere is known as the dynamical core. Advection, or transport, is performed by the dynamical core. It is a central process in many geophysical applications and is a process that often has a quasi-linear underlying behavior. However, over the decades since the advent of numerical modelling, significant effort has gone into developing many flavors of high-order, shape preserving, nonoscillatory, positive definite advection schemes. These schemes are excellent in terms of transporting the quantities of interest in the dynamical core, but they introduce nonlinearity through the use of nonlinear limiters. The linearity of the transport schemes used in Goddard Earth Observing System version 5 (GEOS-5), as well as a number of other schemes, is analyzed using a simple 1D setup. The linearized version of GEOS-5 is then tested using a linear third order scheme in the tangent linear version.
Linear Prediction Using Refined Autocorrelation Function
M. Shahidur Rahman
2007-07-01
Full Text Available This paper proposes a new technique for improving the performance of linear prediction analysis by utilizing a refined version of the autocorrelation function. Problems in analyzing voiced speech using linear prediction occur often due to the harmonic structure of the excitation source, which causes the autocorrelation function to be an aliased version of that of the vocal tract impulse response. To estimate the vocal tract characteristics accurately, however, the effect of aliasing must be eliminated. In this paper, we employ homomorphic deconvolution technique in the autocorrelation domain to eliminate the aliasing effect occurred due to periodicity. The resulted autocorrelation function of the vocal tract impulse response is found to produce significant improvement in estimating formant frequencies. The accuracy of formant estimation is verified on synthetic vowels for a wide range of pitch frequencies typical for male and female speakers. The validity of the proposed method is also illustrated by inspecting the spectral envelopes of natural speech spoken by high-pitched female speaker. The synthesis filter obtained by the current method is guaranteed to be stable, which makes the method superior to many of its alternatives.
Inclusion in the Workplace - Text Version | NREL
Careers Â» Inclusion in the Workplace - Text Version Inclusion in the Workplace - Text Version This is the text version for the Inclusion: Leading by Example video. I'm Martin Keller. I'm the NREL of the laboratory. Another very important element in inclusion is diversity. Because if we have a
A constructive version of AIP revisited
Barros, A.; Hou, T.
2008-01-01
In this paper, we review a constructive version of the Approximation Induction Principle. This version states that bisimilarity of regular processes can be decided by observing only a part of their behaviour. We use this constructive version to formulate a complete inference system for the Algebra
Piles, tabs and overlaps in navigation among documents
Jakobsen, Mikkel Rønne; Hornbæk, Kasper
2010-01-01
Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles. In an experim......Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles....... In an experiment we compared 11 participants’ navigation with these variations and found strong task effects. Overall, overlapping windows were preferred and their structured layout worked well with some tasks. Surprisingly, tabbed documents were efficient in tasks requiring simply finding a document. Piled...... on document navigation and its support by piling....
Cancer Patient Navigator Tasks across the Cancer Care Continuum
Braun, Kathryn L.; Kagawa-Singer, Marjorie; Holden, Alan E. C.; Burhansstipanov, Linda; Tran, Jacqueline H.; Seals, Brenda F.; Corbie-Smith, Giselle; Tsark, JoAnn U.; Harjo, Lisa; Foo, Mary Anne; Ramirez, Amelie G.
2011-01-01
Cancer patient navigation (PN) programs have been shown to increase access to and utilization of cancer care for poor and underserved individuals. Despite mounting evidence of its value, cancer patient navigation is not universally understood or provided. We describe five PN programs and the range of tasks their navigators provide across the cancer care continuum (education and outreach, screening, diagnosis and staging, treatment, survivorship, and end-of-life). Tasks are organized by their potential to make cancer services understandable, available, accessible, affordable, appropriate, and accountable. Although navigators perform similar tasks across the five programs, their specific approaches reflect differences in community culture, context, program setting, and funding. Task lists can inform the development of programs, job descriptions, training, and evaluation. They also may be useful in the move to certify navigators and establish mechanisms for reimbursement for navigation services. PMID:22423178
A fuzzy logic based navigation for mobile robot
Adel Ali S Al-Jumaily; Shamsudin M Amin; Mohamed Khalil
1998-01-01
The main issue of intelligent robot is how to reach its goal safely in real time when it moves in unknown environment. The navigational planning is becoming the central issue in development of real-time autonomous mobile robots. Behaviour based robots have been successful in reacting with dynamic environment but still there are some complexity and challenging problems. Fuzzy based behaviours present as powerful method to solve the real time reactive navigation problems in unknown environment. We shall classify the navigation generation methods, five some characteristics of these methods, explain why fuzzy logic is suitable for the navigation of mobile robot and automated guided vehicle, and describe a reactive navigation that is flexible to react through their behaviours to the change of the environment. Some simulation results will be presented to show the navigation of the robot. (Author)
The generation of gravitational waves. 2. The post-linear formalism revisted
Crowley, R.J.; Thorne, K.S.
1976-04-01
Different versions of the Green's function for the scalar wave equation in weakly curved space-time are compared and contrasted and their mathematical equivalence is demonstrated. Then the DeWitt--DeWitt Green's function is used to construct several alternative versions of the Thorne--Kovacs post-linear formalism for gravitational-wave generation. Finally, it is shown that, in calculations of gravitational bremsstrahlung radiation, some of the presented versions of the post-linear formalism allow one to treat the interacting bodies as point masses, while others do not
Application of X-Ray Pulsar Navigation: A Characterization of the Earth Orbit Trade Space
Yu, Wayne Hong
2016-01-01
tuning analysis of the EKF. The study shows that the closed Earth orbit for XNAV performance is reliant on the orbit semi-major axis and eccentricity as well as orbit inclination. These parameters are the primary drivers of pulsar measurement availability and significantly influence the natural spacecraft orbit dynamics. Sensitivity to initial orbit determination error growth due to the scarcity of XNAV measurements within an orbital period require appropriate timing of initial XNAV measurements. The orbit angles of argument of perigee and right ascension of the ascending node, alongside the other orbit parameters, complete the initial cadence of XNAV measurements. The performance of initial XNAV measurements then propagates throughout the experimental period. The study provides a basis to missions who wish to consider XNAV as a potential navigation source in a closed Earth orbit design. It provides a family of orbit trajectories as well as other modeling considerations needed to effectively evaluate if XNAV is an effective navigation source for a potential mission. As an EKF is sensitive to a linearized estimated state, this study has a direct benefit of providing effective XNAV measurements to maintain spacecraft tracking, independent of other navigation sources. In the particular use case of the SEXTANT mission, it also provides a novel scheduling algorithm which addresses the need to prioritize and manage pulsar observations for effective navigation.
[Cost analysis for navigation in knee endoprosthetics].
Cerha, O; Kirschner, S; Günther, K-P; Lützner, J
2009-12-01
Total knee arthroplasty (TKA) is one of the most frequent procedures in orthopaedic surgery. The outcome depends on a range of factors including alignment of the leg and the positioning of the implant in addition to patient-associated factors. Computer-assisted navigation systems can improve the restoration of a neutral leg alignment. This procedure has been established especially in Europe and North America. The additional expenses are not reimbursed in the German DRG system (Diagnosis Related Groups). In the present study a cost analysis of computer-assisted TKA compared to the conventional technique was performed. The acquisition expenses of various navigation systems (5 and 10 year depreciation), annual costs for maintenance and software updates as well as the accompanying costs per operation (consumables, additional operating time) were considered. The additional operating time was determined on the basis of a meta-analysis according to the current literature. Situations with 25, 50, 100, 200 and 500 computer-assisted TKAs per year were simulated. The amount of the incremental costs of the computer-assisted TKA depends mainly on the annual volume and the additional operating time. A relevant decrease of the incremental costs was detected between 50 and 100 procedures per year. In a model with 100 computer-assisted TKAs per year an additional operating time of 14 mins and a 10 year depreciation of the investment costs, the incremental expenses amount to 300-395 depending on the navigation system. Computer-assisted TKA is associated with additional costs. From an economical point of view an amount of more than 50 procedures per year appears to be favourable. The cost-effectiveness could be estimated if long-term results will show a reduction of revisions or a better clinical outcome.
Surgical navigation in urology: European perspective.
Rassweiler, Jens; Rassweiler, Marie-Claire; Müller, Michael; Kenngott, Hannes; Meinzer, Hans-Peter; Teber, Dogu
2014-01-01
Use of virtual reality to navigate open and endoscopic surgery has significantly evolved during the last decade. Current status of seven most interesting projects inside the European Association of Urology section of uro-technology is summarized with review of literature. Marker-based endoscopic tracking during laparoscopic radical prostatectomy using high-definition technology reduces positive margins. Marker-based endoscopic tracking during laparoscopic partial nephrectomy by mechanical overlay of three-dimensional-segmented virtual anatomy is helpful during planning of trocar placement and dissection of renal hilum. Marker-based, iPAD-assisted puncture of renal collecting system shows more benefit for trainees with reduction of radiation exposure. Three-dimensional laser-assisted puncture of renal collecting system using Uro-Dyna-CT realized in an ex-vivo model enables minimal radiation time. Electromagnetic tracking for puncture of renal collecting system using a sensor at the tip of ureteral catheter worked in an in-vivo model of porcine ureter and kidney. Attitude tracking for ultrasound-guided puncture of renal tumours by accelerometer reduces the puncture error from 4.7 to 1.8 mm. Feasibility of electromagnetic and optical tracking with the da Vinci telemanipulator was shown in vitro as well as using in-vivo model of oesophagectomy. Target registration error was 11.2 mm because of soft-tissue deformation. Intraoperative navigation is helpful during percutaneous puncture collecting system and biopsy of renal tumour using various tracking techniques. Early clinical studies demonstrate advantages of marker-based navigation during laparoscopic radical prostatectomy and partial nephrectomy. Combination of different tracking techniques may further improve this interesting addition to video-assisted surgery.
Embrittlement data base, version 1
Wang, J.A.
1997-08-01
The aging and degradation of light-water-reactor (LWR) pressure vessels is of particular concern because of their relevance to plant integrity and the magnitude of the expected irradiation embrittlement. The radiation embrittlement of reactor pressure vessel (RPV) materials depends on many different factors such as flux, fluence, fluence spectrum, irradiation temperature, and preirradiation material history and chemical compositions. These factors must be considered to reliably predict pressure vessel embrittlement and to ensure the safe operation of the reactor. Based on embrittlement predictions, decisions must be made concerning operating parameters and issues such as low-leakage-fuel management, possible life extension, and the need for annealing the pressure vessel. Large amounts of data from surveillance capsules and test reactor experiments, comprising many different materials and different irradiation conditions, are needed to develop generally applicable damage prediction models that can be used for industry standards and regulatory guides. Version 1 of the Embrittlement Data Base (EDB) is such a comprehensive collection of data resulting from merging version 2 of the Power Reactor Embrittlement Data Base (PR-EDB). Fracture toughness data were also integrated into Version 1 of the EDB. For power reactor data, the current EDB lists the 1,029 Charpy transition-temperature shift data points, which include 321 from plates, 125 from forgoings, 115 from correlation monitor materials, 246 from welds, and 222 from heat-affected-zone (HAZ) materials that were irradiated in 271 capsules from 101 commercial power reactors. For test reactor data, information is available for 1,308 different irradiated sets (352 from plates, 186 from forgoings, 303 from correlation monitor materials, 396 from welds and 71 from HAZs) and 268 different irradiated plus annealed data sets
2013-05-10
AND VICTIM- ~ vAP BLAMING 4. AMERICA, LINEARLY CYCUCAL AF IMT 1768, 19840901, V5 PREVIOUS EDITION WILL BE USED. C2C Jessica Adams Dr. Brissett...his desires, his failings, and his aspirations follow the same general trend throughout history and throughout cultures. The founding fathers sought
Southworth, B.
1985-01-01
The peak of the construction phase of the Stanford Linear Collider, SLC, to achieve 50 GeV electron-positron collisions has now been passed. The work remains on schedule to attempt colliding beams, initially at comparatively low luminosity, early in 1987. (orig./HSI).
Mafra Neto, F.
1992-01-01
The dose of gamma radiation from a linear source of cesium 137 is obtained, presenting two difficulties: oblique filtration of radiation when cross the platinum wall, in different directions, and dose connection due to the scattering by the material mean of propagation. (C.G.C.)
Resistors Improve Ramp Linearity
Kleinberg, L. L.
1982-01-01
Simple modification to bootstrap ramp generator gives more linear output over longer sweep times. New circuit adds just two resistors, one of which is adjustable. Modification cancels nonlinearities due to variations in load on charging capacitor and due to changes in charging current as the voltage across capacitor increases.
LINEAR COLLIDERS: 1992 workshop
Settles, Ron; Coignet, Guy
1992-01-01
As work on designs for future electron-positron linear colliders pushes ahead at major Laboratories throughout the world in a major international collaboration framework, the LC92 workshop held in Garmisch Partenkirchen this summer, attended by 200 machine and particle physicists, provided a timely focus
Brameier, Markus
2007-01-01
Presents a variant of Genetic Programming that evolves imperative computer programs as linear sequences of instructions, in contrast to the more traditional functional expressions or syntax trees. This book serves as a reference for researchers, but also contains sufficient introduction for students and those who are new to the field
Dobbs, David E.
2013-01-01
A direct method is given for solving first-order linear recurrences with constant coefficients. The limiting value of that solution is studied as "n to infinity." This classroom note could serve as enrichment material for the typical introductory course on discrete mathematics that follows a calculus course.
Takeda, Seishi
1992-01-01
The status of R and D of future e + e - linear colliders proposed by the institutions throughout the world is described including the JLC, NLC, VLEPP, CLIC, DESY/THD and TESLA projects. The parameters and RF sources are discussed. (G.P.) 36 refs.; 1 tab
Models for map building and navigation
Penna, M.A.; Jian Wu
1993-01-01
In this paper the authors present several models for solving map building and navigation problems. These models are motivated by biological processes, and presented in the context of artificial neural networks. Since the nodes, weights, and threshold functions of the models all have physical meanings, they can easily predict network topologies and avoid traditional trial-and-error training. On one hand, this makes their models useful in constructing solutions to engineering problems (problems such as those that occur in robotics, for example). On the other hand, this might also contribute to the ability of their models to explain some biological processes, few of which are completely understood at this time
Strategies for navigating the healthcare credit market.
Wareham, T L
2001-04-01
Not-for-profit healthcare organizations are experiencing a tightened credit market due to financial stresses on the healthcare industry such as declining payments, effects of the Balanced Budget Act of 1997, and the shift to outpatient care. In the future, healthcare organizations wanting to access the capital market will be expected to preserve cash as an "insurance policy," offer greater security and stricter covenants, and report financial information on a quarterly basis. To meet these requirements and navigate today's tighter credit market, healthcare financial managers will need to focus on the organization's most reliably profitable areas of business, link strategic and financial issues, and carefully monitor the balance sheet.
Image matching navigation based on fuzzy information
田玉龙; 吴伟仁; 田金文; 柳健
2003-01-01
In conventional image matching methods, the image matching process is mostly based on image statistic information. One aspect neglected by all these methods is that there is much fuzzy information contained in these images. A new fuzzy matching algorithm based on fuzzy similarity for navigation is presented in this paper. Because the fuzzy theory is of the ability of making good description of the fuzzy information contained in images, the image matching method based on fuzzy similarity would look forward to producing good performance results. Experimental results using matching algorithm based on fuzzy information also demonstrate its reliability and practicability.
Fiber optic gyroscopes for vehicle navigation systems
Kumagai, Tatsuya; Soekawa, Hirokazu; Yuhara, Toshiya; Kajioka, Hiroshi; Oho, Shigeru; Sonobe, Hisao
1994-03-01
Fiber optic gyroscopes (FOGs) have been developed for vehicle navigation systems and are used in Toyota Motor Corporation models Mark II, Chaser and Cresta in Japan. Use of FOGs in these systems requires high reliability under a wide range of conditions, especially in a temperature range between -40 and 85 degree(s)C. In addition, a high cost-performance ratio is needed. We have developed optical and electrical systems that are inexpensive and can perform well. They are ready to be mass-produced. FOGs have already been installed in luxury automobiles, and will soon be included in more basic vehicles. We have developed more inexpensive FOGs for this purpose.
Navigating in Higher Education (NiHE)
Thingholm, Hanne Balsby
and students experience during their teaching and studying. The purpose of the survey is to explore differences and similarities in how teachers and students navigate in higher education. The study will provide data for qualifying teaching by developing a Meta- cognitive Oriented Learning Environment (MOLE......). MOLE is characterized by teaching High Order Thinking and thereby achieving Deep Understanding (HOT-DUG). Qualifying education in this way results in deeper understanding for the students regarding not only what to study but also why and how to study, the teachers become more explicit about objectives...
Development of A Plant Navigation System
Furuta, Tomihiko; Nakagawa, Tsuneo; Kubota, Ryuji; Ikeda, Kouji
1998-01-01
A 'Plant Navigation System (PNS)' is under development to assist nuclear power plant (NPP) operators by automatically displaying the plant situation and plant operational procedures on a CRT screen when abnormalities occur. The operation procedures given in a symptom-oriented manual are expressed in a tree - type flowchart (modified PAD). The optimum operation procedure for an NPP is selected automatically using built-in diagnostic logics based on the current status of the NPP. Concerning the plant situation, the PNS displays important information only on the current status of the NPP. A prototype PNS system is being constructed. (authors)
ROBERT autonomous navigation robot with artificial vision
Cipollini, A.; Meo, G.B.; Nanni, V.; Rossi, L.; Taraglio, S.; Ferjancic, C.
1993-01-01
This work, a joint research between ENEA (the Italian National Agency for Energy, New Technologies and the Environment) and DIGlTAL, presents the layout of the ROBERT project, ROBot with Environmental Recognizing Tools, under development in ENEA laboratories. This project aims at the development of an autonomous mobile vehicle able to navigate in a known indoor environment through the use of artificial vision. The general architecture of the robot is shown together with the data and control flow among the various subsystems. Also the inner structure of the latter complete with the functionalities are given in detail
Navigation and history of science: Scurvy
Ignacio Jáuregui-Lobera
2017-09-01
Full Text Available The history of scurvy might be summarized in terms of mystery, death, tenacity and finally success. In this history three very important people deserve special mention, two of them were doctors, the other one was a famous navigator: Lind, Blane and Cook. The first one had the glory of having been the author of the first clinical trial, as we understand it nowadays, with all the criticisms that could be done at present. However, the joint effort of these three men led to the solution of something, which seemed to be an irresolvable mystery.
OSIRIX: open source multimodality image navigation software
Rosset, Antoine; Pysher, Lance; Spadola, Luca; Ratib, Osman
2005-04-01
The goal of our project is to develop a completely new software platform that will allow users to efficiently and conveniently navigate through large sets of multidimensional data without the need of high-end expensive hardware or software. We also elected to develop our system on new open source software libraries allowing other institutions and developers to contribute to this project. OsiriX is a free and open-source imaging software designed manipulate and visualize large sets of medical images: http://homepage.mac.com/rossetantoine/osirix/
Error Analysis of Inertial Navigation Systems Using Test Algorithms
Vaispacher, Tomáš; Bréda, Róbert; Adamčík, František
2015-01-01
Content of this contribution is an issue of inertial sensors errors, specification of inertial measurement units and generating of test signals for Inertial Navigation System (INS). Given the different levels of navigation tasks, part of this contribution is comparison of the actual types of Inertial Measurement Units. Considering this comparison, there is proposed the way of solving inertial sensors errors and their modelling for low – cost inertial navigation applications. The last part is ...
Acoustic Communications and Navigation for Mobile Under-Ice Sensors
2017-02-04
contact below the ice. 15. SUBJECT TERMS Arctic Ocean , Undersea Workstations & Vehicles, Signal Processing, Navigation , Underwater Acoustics 16...Partan, Peter Koski, and Sandipa Singh, "Long Range Acoustic Communications and Navigation in the Arctic", Proc. IEEE/MTS Oceans Conf., Washington, DC...Oct. 2015. Freitag, L., P. Koski, A. Morozov, S. Singh, J. Partan, "Acoustic Communications and Navigation Under Arctic Ice", OCEANS , 2012
Ballistic Aspects of Feasibility for Prospective Satellite Navigation Technologies
L. N. Lysenko
2015-01-01
Full Text Available When modeling the operating processes of ballistics and navigation support it is expedient to make decomposition of the general problem of coordinate-time and navigation support into the typical options of its engineering implementation.As the satellite navigation technologies the paper considers inter-satellite measurement and autonomous navigation mode of differential correction. It also assesses the possibility of their application to improve the accuracy of navigation determinations.Technologies using inter-satellite measurement tools such as GLONASS / GPS equipment, equipment of inter-satellite radio link, astro-optical space based devices are an independent class of navigation technologies.However, each of these options has both advantages and disadvantages that affect the eva luation of the appropriateness and feasibility of their use.The paper separately considers the problem of increasing survivability of space systems and conservation of ground control complex due to introduction of requirements to ensure the independent functioning of spacecraft and application of technologies of ballistics and navigation support, supposing to involve minimum means of automated ground control complex for these purposes.Currently, there is a completely developed theory of autonomous navigation based on astronomical positional gauges, which are used as onboard optical sensors of orientation and stabilization systems.To date, the differential navigation mode is, virtually, the only approach that can allow the olution of tasks in terms of increased accuracy, but with some restrictions.The implementation of differential mode of treatment is carried out through the creation of differential subsystems of the satellite navigation systems. These subsystems are usually divided into wide-range, regional and local ones.Analysis of ballistic aspects to implement discussed navigation technologies allowed us to identify constraints for improving accuracy to define
Strong versions of Bell's theorem
Stapp, H.P.
1994-01-01
Technical aspects of a recently constructed strong version of Bell's theorem are discussed. The theorem assumes neither hidden variables nor factorization, and neither determinism nor counterfactual definiteness. It deals directly with logical connections. Hence its relationship with modal logic needs to be described. It is shown that the proof can be embedded in an orthodox modal logic, and hence its compatibility with modal logic assured, but that this embedding weakens the theorem by introducing as added assumptions the conventionalities of the particular modal logic that is adopted. This weakening is avoided in the recent proof by using directly the set-theoretic conditions entailed by the locality assumption
Rabideau, Gregg; Chien, Steve; Knight, Russell; Schaffer, Steven; Tran, Daniel; Cichy, Benjamin; Sherwood, Robert
2006-01-01
The Automated Scheduling and Planning Environment (ASPEN) computer program has been updated to version 3.0. ASPEN is a modular, reconfigurable, application software framework for solving batch problems that involve reasoning about time, activities, states, and resources. Applications of ASPEN can include planning spacecraft missions, scheduling of personnel, and managing supply chains, inventories, and production lines. ASPEN 3.0 can be customized for a wide range of applications and for a variety of computing environments that include various central processing units and random access memories.
Amplitudes for multiphoton quantum processes in linear optics
UrIas, Jesus
2011-01-01
The prominent role that linear optical networks have acquired in the engineering of photon states calls for physically intuitive and automatic methods to compute the probability amplitudes for the multiphoton quantum processes occurring in linear optics. A version of Wick's theorem for the expectation value, on any vector state, of products of linear operators, in general, is proved. We use it to extract the combinatorics of any multiphoton quantum processes in linear optics. The result is presented as a concise rule to write down directly explicit formulae for the probability amplitude of any multiphoton process in linear optics. The rule achieves a considerable simplification and provides an intuitive physical insight about quantum multiphoton processes. The methodology is applied to the generation of high-photon-number entangled states by interferometrically mixing coherent light with spontaneously down-converted light.
Amplitudes for multiphoton quantum processes in linear optics
Urías, Jesús
2011-07-01
The prominent role that linear optical networks have acquired in the engineering of photon states calls for physically intuitive and automatic methods to compute the probability amplitudes for the multiphoton quantum processes occurring in linear optics. A version of Wick's theorem for the expectation value, on any vector state, of products of linear operators, in general, is proved. We use it to extract the combinatorics of any multiphoton quantum processes in linear optics. The result is presented as a concise rule to write down directly explicit formulae for the probability amplitude of any multiphoton process in linear optics. The rule achieves a considerable simplification and provides an intuitive physical insight about quantum multiphoton processes. The methodology is applied to the generation of high-photon-number entangled states by interferometrically mixing coherent light with spontaneously down-converted light.
The Integrated Tiger Series version 5.0
Laub, Th.W.; Kensek, R.P.; Franke, B.C.; Lorence, L.J.; Crawford, M.J.; Quirk, Th.J.
2005-01-01
The Integrated Tiger Series (ITS) is a powerful and user-friendly software package permitting Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. The package contains programs to perform 1-, 2-, and 3-dimensional simulations. Improvements in the ITS code package since the release of version 3.0 include improved physics, multigroup and adjoint capabilities, Computer-Aided Design geometry tracking, parallel implementations of all ITS codes, and more automated sub-zoning capabilities. These improvements and others are described as current or planned development efforts. The ITS package is currently at version 5.0. (authors)
THE ROLE OF NAVIGATIONAL AIDS IN FLIGHT SAFETY MANAGEMENT WITHIN ICAO GLOBAL AIR NAVIGATION PLAN
Vadim V. Vurobyov
2017-01-01
Full Text Available The development of the global civil aviation is provided on the basis of the ICAO Communication and Surveillance/Air Traffic Management Concept, which has determined the basic strategy for further commercial flight management effectiveness improvement. On the basis of this concept a Global Air Navigation Plan has been developed by ICAO recently. The core strategies of CNS/ATM concept were specified and combined into so-called blocks. Thus the term Global Aviation System block upgrade has been introduced. At the same time, GANP states that the introduction of new procedures and flight management systems will inevitably affect flight safety. Accordingly, there is a task of flight safety management level maintaining, or even increasing within the Global Air Navigation Plan implementation. Various air navigational aids play a significant role in the process as they are directly associated with the new systems and structures introduction.This breeds the new global challenge of flight safety management level change assessment during the introduction of new procedures and systems connected with the use of both navigational aids and instruments. Some aspects of this problem solution are covered in the article.
Cangahuala, L.; Drain, T. R.
1999-01-01
At present, ground navigation support for interplanetary spacecraft requires human intervention for data pre-processing, filtering, and post-processing activities; these actions must be repeated each time a new batch of data is collected by the ground data system.
Fault-tolerant Sensor Fusion for Marine Navigation
Blanke, Mogens
2006-01-01
Reliability of navigation data are critical for steering and manoeuvring control, and in particular so at high speed or in critical phases of a mission. Should faults occur, faulty instruments need be autonomously isolated and faulty information discarded. This paper designs a navigation solution...... where essential navigation information is provided even with multiple faults in instrumentation. The paper proposes a provable correct implementation through auto-generated state-event logics in a supervisory part of the algorithms. Test results from naval vessels document the performance and shows...... events where the fault-tolerant sensor fusion provided uninterrupted navigation data despite temporal instrument defects...
Fault-tolerant and Diagnostic Methods for Navigation
Blanke, Mogens
2003-01-01
to diagnose faults and autonomously provide valid navigation data, disregarding any faulty sensor data and use sensor fusion to obtain a best estimate for users. This paper discusses how diagnostic and fault-tolerant methods are applicable in marine systems. An example chosen is sensor fusion for navigation......Precise and reliable navigation is crucial, and for reasons of safety, essential navigation instruments are often duplicated. Hardware redundancy is mostly used to manually switch between instruments should faults occur. In contrast, diagnostic methods are available that can use analytic redundancy...
75 FR 6215 - Houston/Galveston Navigation Safety Advisory Committee
2010-02-08
... groups will meet in Houston, Texas to discuss waterway improvements, aids to navigation, area projects...; (b) Dredging subcommittee report; (c) Technology subcommittee report; (d) Waterways Optimization...
Expected Navigation Flight Performance for the Magnetospheric Multiscale (MMS) Mission
Olson, Corwin; Wright, Cinnamon; Long, Anne
2012-01-01
The Magnetospheric Multiscale (MMS) mission consists of four formation-flying spacecraft placed in highly eccentric elliptical orbits about the Earth. The primary scientific mission objective is to study magnetic reconnection within the Earth s magnetosphere. The baseline navigation concept is the independent estimation of each spacecraft state using GPS pseudorange measurements (referenced to an onboard Ultra Stable Oscillator) and accelerometer measurements during maneuvers. State estimation for the MMS spacecraft is performed onboard each vehicle using the Goddard Enhanced Onboard Navigation System, which is embedded in the Navigator GPS receiver. This paper describes the latest efforts to characterize expected navigation flight performance using upgraded simulation models derived from recent analyses.
Visual navigation using edge curve matching for pinpoint planetary landing
Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei
2018-05-01
Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.
Navigating Institutions and Institutional Leadership to Address Sexual Violence
Sisneros, Kathy; Rivera, Monica
2018-01-01
Using an institutional example, this chapter offers strategies to effectively navigate institutional culture, processes, and structures to engage the entire campus community in addressing sexual violence.
Carny, P.; Suchon, D.; Chyly, M.; Smejkalova, E.; Fabova, V.
2008-01-01
ESTE EU is information system and software for radiological impacts assessment to the territory of the country in case of radiation accident inside/outside of the country .The program enables to model dispersion of radioactive clouds in small-scale and meso-scale. The system enables the user to estimate prediction of the source term (release to the atmosphere ) for any point of radiation/nuclear accident in Europe (for any point of the release, but especially for the sites of European power reactors ). The system enables to utilize results of real radiological monitoring in the process of source term estimation. Radiological impacts of release to the atmosphere are modelled and calculated across the Europe and displayed in the geographical information system (GIS). The school version of ESTE EU is intended for students of the universities which are interested in or could work in the field of emergency response, radiological and nuclear accidents, dispersion modelling, radiological impacts calculation and urgent or preventive protective measures implementation. The school version of ESTE EU is planned to be donated to specialized departments of faculties in Slovakia, Czech Republic, etc. System can be fully operated in Slovak, Czech or English language. (authors)
Carny, P.; Suchon, D.; Chyly, M.; Smejkalova, E.; Fabova, V.
2009-01-01
ESTE EU is information system and software for radiological impacts assessment to the territory of the country in case of radiation accident inside/outside of the country .The program enables to model dispersion of radioactive clouds in small-scale and meso-scale. The system enables the user to estimate prediction of the source term (release to the atmosphere ) for any point of radiation/nuclear accident in Europe (for any point of the release, but especially for the sites of European power reactors ). The system enables to utilize results of real radiological monitoring in the process of source term estimation. Radiological impacts of release to the atmosphere are modelled and calculated across the Europe and displayed in the geographical information system (GIS). The school version of ESTE EU is intended for students of the universities which are interested in or could work in the field of emergency response, radiological and nuclear accidents, dispersion modelling, radiological impacts calculation and urgent or preventive protective measures implementation. The school version of ESTE EU is planned to be donated to specialized departments of faculties in Slovakia, Czech Republic, etc. System can be fully operated in Slovak, Czech or English language. (authors)
SPORTS (version 1) user's guide
Chatoorgoon, V.; Thibeault, P.R.
1985-06-01
SPORTS is a transient one-dimensional thermalhydraulic code formulated from the non-linear time dependent conservation equations and designed to investigate two-phase flow stability. The SPORTS Users' Guide contains some features of the code, a brief description of the program environment and access, and a description of the input data complete with a sample problem
Ratib, Osman; Rosset, Antoine; Dahlbom, Magnus; Czernin, Johannes
2005-04-01
Display and interpretation of multi dimensional data obtained from the combination of 3D data acquired from different modalities (such as PET-CT) require complex software tools allowing the user to navigate and modify the different image parameters. With faster scanners it is now possible to acquire dynamic images of a beating heart or the transit of a contrast agent adding a fifth dimension to the data. We developed a DICOM-compliant software for real time navigation in very large sets of 5 dimensional data based on an intuitive multidimensional jog-wheel widely used by the video-editing industry. The software, provided under open source licensing, allows interactive, single-handed, navigation through 3D images while adjusting blending of image modalities, image contrast and intensity and the rate of cine display of dynamic images. In this study we focused our effort on the user interface and means for interactively navigating in these large data sets while easily and rapidly changing multiple parameters such as image position, contrast, intensity, blending of colors, magnification etc. Conventional mouse-driven user interface requiring the user to manipulate cursors and sliders on the screen are too cumbersome and slow. We evaluated several hardware devices and identified a category of multipurpose jogwheel device that is used in the video-editing industry that is particularly suitable for rapidly navigating in five dimensions while adjusting several display parameters interactively. The application of this tool will be demonstrated in cardiac PET-CT imaging and functional cardiac MRI studies.
Finite-dimensional linear algebra
Gockenbach, Mark S
2010-01-01
Some Problems Posed on Vector SpacesLinear equationsBest approximationDiagonalizationSummaryFields and Vector SpacesFields Vector spaces Subspaces Linear combinations and spanning sets Linear independence Basis and dimension Properties of bases Polynomial interpolation and the Lagrange basis Continuous piecewise polynomial functionsLinear OperatorsLinear operatorsMore properties of linear operatorsIsomorphic vector spaces Linear operator equations Existence and uniqueness of solutions The fundamental theorem; inverse operatorsGaussian elimination Newton's method Linear ordinary differential eq
Non-Linear Back-propagation: Doing Back-Propagation withoutDerivatives of the Activation Function
Hertz, John; Krogh, Anders Stærmose; Lautrup, Benny
1997-01-01
The conventional linear back-propagation algorithm is replaced by a non-linear version, which avoids the necessity for calculating the derivative of the activation function. This may be exploited in hardware realizations of neural processors. In this paper we derive the non-linear back...
Structure and navigation for electronic publishing
Tillinghast, John; Beretta, Giordano B.
1998-01-01
The sudden explosion of the World Wide Web as a new publication medium has given a dramatic boost to the electronic publishing industry, which previously was a limited market centered around CD-ROMs and on-line databases. While the phenomenon has parallels to the advent of the tabloid press in the middle of last century, the electronic nature of the medium brings with it the typical characteristic of 4th wave media, namely the acceleration in its propagation speed and the volume of information. Consequently, e-publications are even flatter than print media; Shakespeare's Romeo and Juliet share the same computer screen with a home-made plagiarized copy of Deep Throat. The most touted tool for locating useful information on the World Wide Web is the search engine. However, due to the medium's flatness, sought information is drowned in a sea of useless information. A better solution is to build tools that allow authors to structure information so that it can easily be navigated. We experimented with the use of ontologies as a tool to formulate structures for information about a specific topic, so that related concepts are placed in adjacent locations and can easily be navigated using simple and ergonomic user models. We describe our effort in building a World Wide Web based photo album that is shared among a small network of people.
Tactile object exploration using cursor navigation sensors
Kraft, Dirk; Bierbaum, Alexander; Kjaergaard, Morten
2009-01-01
In robotic applications tactile sensor systems serve the purpose of localizing a contact point and measuring contact forces. We have investigated the applicability of a sensorial device commonly used in cursor navigation technology for tactile sensing in robotics. We show the potential of this se......In robotic applications tactile sensor systems serve the purpose of localizing a contact point and measuring contact forces. We have investigated the applicability of a sensorial device commonly used in cursor navigation technology for tactile sensing in robotics. We show the potential...... of this sensor for active haptic exploration. More specifically, we present experiments and results which demonstrate the extraction of relevant object properties such as local shape, weight and elasticity using this technology. Besides its low price due to mass production and its modularity, an interesting...... aspect of this sensor is that beside a localization of contact points and measurement of the contact normal force also shear forces can be measured. This is relevant for many applications such as surface normal estimation and weight measurements. Scalable tactile sensor arrays have been developed...
Navigating actions through the rodent parietal cortex
Jonathan R. Whitlock
2014-05-01
Full Text Available The posterior parietal cortex (PPC participates in a manifold of cognitive functions, including visual attention, working memory, spatial processing and movement planning. Given the vast interconnectivity of PPC with sensory and motor areas, it is not surprising that neuronal recordings show that PPC often encodes mixtures of spatial information as well as the movements required to reach a goal. Recent work sought to discern the relative strength of spatial versus motor signaling in PPC by recording single unit activity in PPC of freely behaving rats during selective changes in either the spatial layout of the local environment or in the pattern of locomotor behaviors executed during navigational tasks. The results revealed unequivocally a predominant sensitivity of PPC neurons to locomotor action structure, with subsets of cells even encoding upcoming movements more than 1 second in advance. In light of these and other recent findings in the field, I propose that one of the key contributions of PPC to navigation is the synthesis of goal-directed behavioral sequences, and that the rodent PPC may serve as an apt system to investigate cellular mechanisms for spatial motor planning as traditionally studied in humans and monkeys.
Extraction of user's navigation commands from upper body force interaction in walker assisted gait.
Frizera Neto, Anselmo; Gallego, Juan A; Rocon, Eduardo; Pons, José L; Ceres, Ramón
2010-08-05
The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i) the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii) the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 +/- 0.358).10(-2) kgf) and delay ((1.897 +/- 0.3697).10(1)ms). A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.
33 CFR 150.705 - What are the requirements for maintaining and inspecting aids to navigation?
2010-07-01
... maintaining and inspecting aids to navigation? 150.705 Section 150.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.705 What are the requirements for maintaining and inspecting aids to navigation? (a) All...
Linearity and Non-linearity of Photorefractive effect in Materials ...
In this paper we have studied the Linearity and Non-linearity of Photorefractive effect in materials using the band transport model. For low light beam intensities the change in the refractive index is proportional to the electric field for linear optics while for non- linear optics the change in refractive index is directly proportional ...
Linearly Refined Session Types
Pedro Baltazar
2012-11-01
Full Text Available Session types capture precise protocol structure in concurrent programming, but do not specify properties of the exchanged values beyond their basic type. Refinement types are a form of dependent types that can address this limitation, combining types with logical formulae that may refer to program values and can constrain types using arbitrary predicates. We present a pi calculus with assume and assert operations, typed using a session discipline that incorporates refinement formulae written in a fragment of Multiplicative Linear Logic. Our original combination of session and refinement types, together with the well established benefits of linearity, allows very fine-grained specifications of communication protocols in which refinement formulae are treated as logical resources rather than persistent truths.
Kuznetsov, N.; Maz'ya, V.; Vainberg, B.
2002-08-01
This book gives a self-contained and up-to-date account of mathematical results in the linear theory of water waves. The study of waves has many applications, including the prediction of behavior of floating bodies (ships, submarines, tension-leg platforms etc.), the calculation of wave-making resistance in naval architecture, and the description of wave patterns over bottom topography in geophysical hydrodynamics. The first section deals with time-harmonic waves. Three linear boundary value problems serve as the approximate mathematical models for these types of water waves. The next section uses a plethora of mathematical techniques in the investigation of these three problems. The techniques used in the book include integral equations based on Green's functions, various inequalities between the kinetic and potential energy and integral identities which are indispensable for proving the uniqueness theorems. The so-called inverse procedure is applied to constructing examples of non-uniqueness, usually referred to as 'trapped nodes.'
The International Linear Collider
List Benno
2014-04-01
Full Text Available The International Linear Collider (ILC is a proposed e+e− linear collider with a centre-of-mass energy of 200–500 GeV, based on superconducting RF cavities. The ILC would be an ideal machine for precision studies of a light Higgs boson and the top quark, and would have a discovery potential for new particles that is complementary to that of LHC. The clean experimental conditions would allow the operation of detectors with extremely good performance; two such detectors, ILD and SiD, are currently being designed. Both make use of novel concepts for tracking and calorimetry. The Japanese High Energy Physics community has recently recommended to build the ILC in Japan.
The International Linear Collider
List, Benno
2014-04-01
The International Linear Collider (ILC) is a proposed e+e- linear collider with a centre-of-mass energy of 200-500 GeV, based on superconducting RF cavities. The ILC would be an ideal machine for precision studies of a light Higgs boson and the top quark, and would have a discovery potential for new particles that is complementary to that of LHC. The clean experimental conditions would allow the operation of detectors with extremely good performance; two such detectors, ILD and SiD, are currently being designed. Both make use of novel concepts for tracking and calorimetry. The Japanese High Energy Physics community has recently recommended to build the ILC in Japan.
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....... of these criteria are widely used ones, while the remaining four are ones derived from the H-principle of mathematical modeling. Many examples from practice show that the criteria derived from the H-principle function better than the known and popular criteria for the number of components. We shall briefly review...
Goldowsky, Michael P. (Inventor)
1987-01-01
A reciprocating linear motor is formed with a pair of ring-shaped permanent magnets having opposite radial polarizations, held axially apart by a nonmagnetic yoke, which serves as an axially displaceable armature assembly. A pair of annularly wound coils having axial lengths which differ from the axial lengths of the permanent magnets are serially coupled together in mutual opposition and positioned with an outer cylindrical core in axial symmetry about the armature assembly. One embodiment includes a second pair of annularly wound coils serially coupled together in mutual opposition and an inner cylindrical core positioned in axial symmetry inside the armature radially opposite to the first pair of coils. Application of a potential difference across a serial connection of the two pairs of coils creates a current flow perpendicular to the magnetic field created by the armature magnets, thereby causing limited linear displacement of the magnets relative to the coils.
Henneaux, Marc; Teitelboim, Claudio
2005-01-01
We show that duality transformations of linearized gravity in four dimensions, i.e., rotations of the linearized Riemann tensor and its dual into each other, can be extended to the dynamical fields of the theory so as to be symmetries of the action and not just symmetries of the equations of motion. Our approach relies on the introduction of two superpotentials, one for the spatial components of the spin-2 field and the other for their canonically conjugate momenta. These superpotentials are two-index, symmetric tensors. They can be taken to be the basic dynamical fields and appear locally in the action. They are simply rotated into each other under duality. In terms of the superpotentials, the canonical generator of duality rotations is found to have a Chern-Simons-like structure, as in the Maxwell case
Phinney, N.
1992-01-01
The SLAC Linear Collider has begun a new era of operation with the SLD detector. During 1991 there was a first engineering run for the SLD in parallel with machine improvements to increase luminosity and reliability. For the 1992 run, a polarized electron source was added and more than 10,000 Zs with an average of 23% polarization have been logged by the SLD. This paper discusses the performance of the SLC in 1991 and 1992 and the technical advances that have produced higher luminosity. Emphasis will be placed on issues relevant to future linear colliders such as producing and maintaining high current, low emittance beams and focusing the beams to the micron scale for collisions. (Author) tab., 2 figs., 18 refs
Linear waves and instabilities
Bers, A.
1975-01-01
The electrodynamic equations for small-amplitude waves and their dispersion relation in a homogeneous plasma are outlined. For such waves, energy and momentum, and their flow and transformation, are described. Perturbation theory of waves is treated and applied to linear coupling of waves, and the resulting instabilities from such interactions between active and passive waves. Linear stability analysis in time and space is described where the time-asymptotic, time-space Green's function for an arbitrary dispersion relation is developed. The perturbation theory of waves is applied to nonlinear coupling, with particular emphasis on pump-driven interactions of waves. Details of the time--space evolution of instabilities due to coupling are given. (U.S.)
Extended linear chain compounds
Linear chain substances span a large cross section of contemporary chemistry ranging from covalent polymers, to organic charge transfer com plexes to nonstoichiometric transition metal coordination complexes. Their commonality, which coalesced intense interest in the theoretical and exper imental solid state physics/chemistry communities, was based on the obser vation that these inorganic and organic polymeric substrates exhibit striking metal-like electrical and optical properties. Exploitation and extension of these systems has led to the systematic study of both the chemistry and physics of highly and poorly conducting linear chain substances. To gain a salient understanding of these complex materials rich in anomalous aniso tropic electrical, optical, magnetic, and mechanical properties, the conver gence of diverse skills and talents was required. The constructive blending of traditionally segregated disciplines such as synthetic and physical organic, inorganic, and polymer chemistry, crystallog...
Diamond, Jared M.
1966-01-01
1. The relation between osmotic gradient and rate of osmotic water flow has been measured in rabbit gall-bladder by a gravimetric procedure and by a rapid method based on streaming potentials. Streaming potentials were directly proportional to gravimetrically measured water fluxes. 2. As in many other tissues, water flow was found to vary with gradient in a markedly non-linear fashion. There was no consistent relation between the water permeability and either the direction or the rate of water flow. 3. Water flow in response to a given gradient decreased at higher osmolarities. The resistance to water flow increased linearly with osmolarity over the range 186-825 m-osM. 4. The resistance to water flow was the same when the gall-bladder separated any two bathing solutions with the same average osmolarity, regardless of the magnitude of the gradient. In other words, the rate of water flow is given by the expression (Om — Os)/[Ro′ + ½k′ (Om + Os)], where Ro′ and k′ are constants and Om and Os are the bathing solution osmolarities. 5. Of the theories advanced to explain non-linear osmosis in other tissues, flow-induced membrane deformations, unstirred layers, asymmetrical series-membrane effects, and non-osmotic effects of solutes could not explain the results. However, experimental measurements of water permeability as a function of osmolarity permitted quantitative reconstruction of the observed water flow—osmotic gradient curves. Hence non-linear osmosis in rabbit gall-bladder is due to a decrease in water permeability with increasing osmolarity. 6. The results suggest that aqueous channels in the cell membrane behave as osmometers, shrinking in concentrated solutions of impermeant molecules and thereby increasing membrane resistance to water flow. A mathematical formulation of such a membrane structure is offered. PMID:5945254
Fundamentals of linear algebra
Dash, Rajani Ballav
2008-01-01
FUNDAMENTALS OF LINEAR ALGEBRA is a comprehensive Text Book, which can be used by students and teachers of All Indian Universities. The Text has easy, understandable form and covers all topics of UGC Curriculum. There are lots of worked out examples which helps the students in solving the problems without anybody's help. The Problem sets have been designed keeping in view of the questions asked in different examinations.
Sander, K F
1964-01-01
Linear Network Theory covers the significant algebraic aspect of network theory, with minimal reference to practical circuits. The book begins the presentation of network analysis with the exposition of networks containing resistances only, and follows it up with a discussion of networks involving inductance and capacity by way of the differential equations. Classification and description of certain networks, equivalent networks, filter circuits, and network functions are also covered. Electrical engineers, technicians, electronics engineers, electricians, and students learning the intricacies
Superconducting linear colliders
Anon.
1990-01-01
The advantages of superconducting radiofrequency (SRF) for particle accelerators have been demonstrated by successful operation of systems in the TRISTAN and LEP electron-positron collider rings respectively at the Japanese KEK Laboratory and at CERN. If performance continues to improve and costs can be lowered, this would open an attractive option for a high luminosity TeV (1000 GeV) linear collider
Perturbed asymptotically linear problems
Bartolo, R.; Candela, A. M.; Salvatore, A.
2012-01-01
The aim of this paper is investigating the existence of solutions of some semilinear elliptic problems on open bounded domains when the nonlinearity is subcritical and asymptotically linear at infinity and there is a perturbation term which is just continuous. Also in the case when the problem has not a variational structure, suitable procedures and estimates allow us to prove that the number of distinct crtitical levels of the functional associated to the unperturbed problem is "stable" unde...
Miniature linear cooler development
Pruitt, G.R.
1993-01-01
An overview is presented of the status of a family of miniature linear coolers currently under development by Hughes Aircraft Co. for use in hand held, volume limited or power limited infrared applications. These coolers, representing the latest additions to the Hughes family of TOP trademark [twin-opposed piston] linear coolers, have been fabricated and tested in three different configurations. Each configuration is designed to utilize a common compressor assembly resulting in reduced manufacturing costs. The baseline compressor has been integrated with two different expander configurations and has been operated with two different levels of input power. These various configuration combinations offer a wide range of performance and interface characteristics which may be tailored to applications requiring limited power and size without significantly compromising cooler capacity or cooldown characteristics. Key cooler characteristics and test data are summarized for three combinations of cooler configurations which are representative of the versatility of this linear cooler design. Configurations reviewed include the shortened coldfinger [1.50 to 1.75 inches long], limited input power [less than 17 Watts] for low power availability applications; the shortened coldfinger with higher input power for lightweight, higher performance applications; and coldfingers compatible with DoD 0.4 Watt Common Module coolers for wider range retrofit capability. Typical weight of these miniature linear coolers is less than 500 grams for the compressor, expander and interconnecting transfer line. Cooling capacity at 80K at room ambient conditions ranges from 400 mW to greater than 550 mW. Steady state power requirements for maintaining a heat load of 150 mW at 80K has been shown to be less than 8 Watts. Ongoing reliability growth testing is summarized including a review of the latest test article results
Avram Mihai
2017-01-01
Full Text Available The paper presents a linear pneumatic actuator with short working stroke. It consists of a pneumatic motor (a simple stroke cylinder or a membrane chamber, two 2/2 pneumatic distributors “all or nothing” electrically commanded for controlling the intake/outtake flow to/from the active chamber of the motor, a position transducer and a microcontroller. There is also presented the theoretical analysis (mathematical modelling and numerical simulation accomplished.
Avram Mihai; Niţu Constantin; Bucşan Constantin; Grămescu Bogdan
2017-01-01
The paper presents a linear pneumatic actuator with short working stroke. It consists of a pneumatic motor (a simple stroke cylinder or a membrane chamber), two 2/2 pneumatic distributors “all or nothing” electrically commanded for controlling the intake/outtake flow to/from the active chamber of the motor, a position transducer and a microcontroller. There is also presented the theoretical analysis (mathematical modelling and numerical simulation) accomplished.
Scheffel, J.
1984-03-01
The linear Grad-Shafranov equation for a toroidal, axisymmetric plasma is solved analytically. Exact solutions are given in terms of confluent hyper-geometric functions. As an alternative, simple and accurate WKBJ solutions are presented. With parabolic pressure profiles, both hollow and peaked toroidal current density profiles are obtained. As an example the equilibrium of a z-pinch with a square-shaped cross section is derived.(author)
Buttram, M.T.; Ginn, J.W.
1988-06-21
A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.
A simultaneous navigation and radiation evasion algorithm (SNARE)
Khasawneh, Mohammed A., E-mail: mkha@ieee.org [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Jaradat, Mohammad A., E-mail: majaradat@just.edu.jo [Department of Mechanical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan); Al-Shboul, Zeina Aman M., E-mail: xeinaaman@gmail.com [Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 221 10 (Jordan)
2013-12-15
Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm
A simultaneous navigation and radiation evasion algorithm (SNARE)
Khasawneh, Mohammed A.; Jaradat, Mohammad A.; Al-Shboul, Zeina Aman M.
2013-01-01
Highlights: • A new navigation algorithm for radiation evasion around nuclear facilities. • An optimization criteria minimized under algorithm operation. • A man-borne device guiding the occupational worker towards paths that warrant least radiation × time products. • Benefits of using localized navigation as opposed to global navigation schemas. • A path discrimination function for finding the navigational paths exhibiting the least amounts of radiation. - Abstract: In this paper, we address the issue of localization as pertains to indoor navigation under radiation contaminated environments. In this context, navigation, in the absence of any GPS signals, is guided by the location of the sensors that make up the entire wireless sensor network in a given locality within a nuclear facility. It, also, draws on the radiation levels as measured by the sensors around a given locale. Here, localization is inherently embedded into the algorithm presented in (Khasawneh et al., 2011a, 2011b) which was designed to provide navigational guidance to optimize any of two criteria: “Radiation Evasion” and “Nearest Exit”. As such, the algorithm can either be applied to setting a navigational “lowest” radiation exposure path from an initial point A to some other point B; a case typical of occupational workers performing maintenance operations around the facility; or providing a radiation-safe passage from point A to the nearest exit. Algorithm's navigational performance is tested under statistical reference, wherein for a given number of runs (trials) algorithm performance is evaluated as a function of the number of steps of look-ahead it uses to acquire navigational information, and is compared against the performance of the renowned Dijkstra global navigation algorithm. This is done with reference to the amount of (radiation × time) product and that of the time needed to reach an exit point, under the two optimization criteria. To evaluate algorithm
Parametric Linear Dynamic Logic
Peter Faymonville
2014-08-01
Full Text Available We introduce Parametric Linear Dynamic Logic (PLDL, which extends Linear Dynamic Logic (LDL by temporal operators equipped with parameters that bound their scope. LDL was proposed as an extension of Linear Temporal Logic (LTL that is able to express all ω-regular specifications while still maintaining many of LTL's desirable properties like an intuitive syntax and a translation into non-deterministic Büchi automata of exponential size. But LDL lacks capabilities to express timing constraints. By adding parameterized operators to LDL, we obtain a logic that is able to express all ω-regular properties and that subsumes parameterized extensions of LTL like Parametric LTL and PROMPT-LTL. Our main technical contribution is a translation of PLDL formulas into non-deterministic Büchi word automata of exponential size via alternating automata. This yields a PSPACE model checking algorithm and a realizability algorithm with doubly-exponential running time. Furthermore, we give tight upper and lower bounds on optimal parameter values for both problems. These results show that PLDL model checking and realizability are not harder than LTL model checking and realizability.
Emma, P.
1995-01-01
The Stanford Linear Collider (SLC) is the first and only high-energy e + e - linear collider in the world. Its most remarkable features are high intensity, submicron sized, polarized (e - ) beams at a single interaction point. The main challenges posed by these unique characteristics include machine-wide emittance preservation, consistent high intensity operation, polarized electron production and transport, and the achievement of a high degree of beam stability on all time scales. In addition to serving as an important machine for the study of Z 0 boson production and decay using polarized beams, the SLC is also an indispensable source of hands-on experience for future linear colliders. Each new year of operation has been highlighted with a marked improvement in performance. The most significant improvements for the 1994-95 run include new low impedance vacuum chambers for the damping rings, an upgrade to the optics and diagnostics of the final focus systems, and a higher degree of polarization from the electron source. As a result, the average luminosity has nearly doubled over the previous year with peaks approaching 10 30 cm -2 s -1 and an 80% electron polarization at the interaction point. These developments as well as the remaining identifiable performance limitations will be discussed
Bank erosion of navigation canals in the western and central Gulf of Mexico
Thatcher, Cindy A.; Hartley, Stephen B.; Wilson, Scott A.
2011-01-01
Erosion of navigation canal banks is a direct cause of land loss, but there has been little quantitative analysis to determine why certain major canals exhibit faster widening rates (indicative of erosion) than others in the coastal zones of Texas, Louisiana, Mississippi, and Alabama. We hypothesize that navigation canals exhibit varying rates of erosion based on soil properties of the embankment substrate, vegetation type, geologic region (derived from digital versions of state geologic maps), and the presence or absence of canal bank armaments (that is, rock rip-rap, concrete bulkheads, or other shoreline protection structures). The first objective of this project was to map the shoreline position and substrate along both banks of the navigation canals, which were digitized from 3 different time periods of aerial photography spanning the years of 1978/79 to 2005/06. The second objective was to quantify the erosion rates of the navigation canals in the study area and to determine whether differences in erosion rates are related to embankment substrate, vegetation type, geologic region, or soil type. To measure changes in shoreline position over time, transects spaced at 50-m (164-ft) intervals were intersected with shorelines from all three time periods, and an annual rate of change was calculated for each transect. Mean annual rates of shoreline change ranged from 1.75 m/year (5.74 ft/year) on the west side of the Atchafalaya River, La., where there was shoreline advancement or canal narrowing, to -3.29 m/year (-10.79 ft/year) on the south side of the Theodore Ship Channel, Ala., where there was shoreline retreat or erosion. Statistical analysis indicated that there were significant differences in shoreline retreat rates according to geologic region and marsh vegetation type, and a weak relationship with soil organic content. This information can be used to better estimate future land loss rates associated with navigation canals and to prioritize the location of
SPAM- SPECTRAL ANALYSIS MANAGER (UNIX VERSION)
Solomon, J. E.
1994-01-01
The Spectral Analysis Manager (SPAM) was developed to allow easy qualitative analysis of multi-dimensional imaging spectrometer data. Imaging spectrometers provide sufficient spectral sampling to define unique spectral signatures on a per pixel basis. Thus direct material identification becomes possible for geologic studies. SPAM provides a variety of capabilities for carrying out interactive analysis of the massive and complex datasets associated with multispectral remote sensing observations. In addition to normal image processing functions, SPAM provides multiple levels of on-line help, a flexible command interpretation, graceful error recovery, and a program structure which can be implemented in a variety of environments. SPAM was designed to be visually oriented and user friendly with the liberal employment of graphics for rapid and efficient exploratory analysis of imaging spectrometry data. SPAM provides functions to enable arithmetic manipulations of the data, such as normalization, linear mixing, band ratio discrimination, and low-pass filtering. SPAM can be used to examine the spectra of an individual pixel or the average spectra over a number of pixels. SPAM also supports image segmentation, fast spectral signature matching, spectral library usage, mixture analysis, and feature extraction. High speed spectral signature matching is performed by using a binary spectral encoding algorithm to separate and identify mineral components present in the scene. The same binary encoding allows automatic spectral clustering. Spectral data may be entered from a digitizing tablet, stored in a user library, compared to the master library containing mineral standards, and then displayed as a timesequence spectral movie. The output plots, histograms, and stretched histograms produced by SPAM can be sent to a lineprinter, stored as separate RGB disk files, or sent to a Quick Color Recorder. SPAM is written in C for interactive execution and is available for two different
Sommer, Stefan Horst; Lauze, Francois Bernard; Hauberg, Søren
2010-01-01
, we present a comparison between the non-linear analog of Principal Component Analysis, Principal Geodesic Analysis, in its linearized form and its exact counterpart that uses true intrinsic distances. We give examples of datasets for which the linearized version provides good approximations...... and for which it does not. Indicators for the differences between the two versions are then developed and applied to two examples of manifold valued data: outlines of vertebrae from a study of vertebral fractures and spacial coordinates of human skeleton end-effectors acquired using a stereo camera and tracking...
A Low-Cost, Passive Navigation Training System for Image-Guided Spinal Intervention.
Lorias-Espinoza, Daniel; Carranza, Vicente González; de León, Fernando Chico-Ponce; Escamirosa, Fernando Pérez; Martinez, Arturo Minor
2016-11-01
Navigation technology is used for training in various medical specialties, not least image-guided spinal interventions. Navigation practice is an important educational component that allows residents to understand how surgical instruments interact with complex anatomy and to learn basic surgical skills such as the tridimensional mental interpretation of bidimensional data. Inexpensive surgical simulators for spinal surgery, however, are lacking. We therefore designed a low-cost spinal surgery simulator (Spine MovDigSys 01) to allow 3-dimensional navigation via 2-dimensional images without altering or limiting the surgeon's natural movement. A training system was developed with an anatomical lumbar model and 2 webcams to passively digitize surgical instruments under MATLAB software control. A proof-of-concept recognition task (vertebral body cannulation) and a pilot test of the system with 12 neuro- and orthopedic surgeons were performed to obtain feedback on the system. Position, orientation, and kinematic variables were determined and the lateral, posteroanterior, and anteroposterior views obtained. The system was tested with a proof-of-concept experimental task. Operator metrics including time of execution (t), intracorporeal length (d), insertion angle (α), average speed (v¯), and acceleration (a) were obtained accurately. These metrics were converted into assessment metrics such as smoothness of operation and linearity of insertion. Results from initial testing are shown and the system advantages and disadvantages described. This low-cost spinal surgery training system digitized the position and orientation of the instruments and allowed image-guided navigation, the generation of metrics, and graphic recording of the instrumental route. Spine MovDigSys 01 is useful for development of basic, noninnate skills and allows the novice apprentice to quickly and economically move beyond the basics. Copyright © 2016 Elsevier Inc. All rights reserved.
A parallel version of a multigrid algorithm for isotropic transport equations
Manteuffel, T.; McCormick, S.; Yang, G.; Morel, J.; Oliveira, S.
1994-01-01
The focus of this paper is on a parallel algorithm for solving the transport equations in a slab geometry using multigrid. The spatial discretization scheme used is a finite element method called the modified linear discontinuous (MLD) scheme. The MLD scheme represents a lumped version of the standard linear discontinuous (LD) scheme. The parallel algorithm was implemented on the Connection Machine 2 (CM2). Convergence rates and timings for this algorithm on the CM2 and Cray-YMP are shown
Guohu Feng
2012-06-01
Full Text Available A matrix Kalman filter (MKF has been implemented for an integrated navigation system using visual/inertial/magnetic sensors. The MKF rearranges the original nonlinear process model in a pseudo-linear process model. We employ the observability rank criterion based on Lie derivatives to verify the conditions under which the nonlinear system is observable. It has been proved that such observability conditions are: (a at least one degree of rotational freedom is excited, and (b at least two linearly independent horizontal lines and one vertical line are observed. Experimental results have validated the correctness of these observability conditions.
Finding Home: Landmark Ambiguity in Human Navigation
Simon Jetzschke
2017-07-01
Full Text Available Memories of places often include landmark cues, i.e., information provided by the spatial arrangement of distinct objects with respect to the target location. To study how humans combine landmark information for navigation, we conducted two experiments: To this end, participants were either provided with auditory landmarks while walking in a large sports hall or with visual landmarks while walking on a virtual-reality treadmill setup. We found that participants cannot reliably locate their home position due to ambiguities in the spatial arrangement when only one or two uniform landmarks provide cues with respect to the target. With three visual landmarks that look alike, the task is solved without ambiguity, while audio landmarks need to play three unique sounds for a similar performance. This reduction in ambiguity through integration of landmark information from 1, 2, and 3 landmarks is well modeled using a probabilistic approach based on maximum likelihood estimation. Unlike any deterministic model of human navigation (based e.g., on distance or angle information, this probabilistic model predicted both the precision and accuracy of the human homing performance. To further examine how landmark cues are integrated we introduced systematic conflicts in the visual landmark configuration between training of the home position and tests of the homing performance. The participants integrated the spatial information from each landmark near-optimally to reduce spatial variability. When the conflict becomes big, this integration breaks down and precision is sacrificed for accuracy. That is, participants return again closer to the home position, because they start ignoring the deviant third landmark. Relying on two instead of three landmarks, however, goes along with responses that are scattered over a larger area, thus leading to higher variability. To model the breakdown of integration with increasing conflict, the probabilistic model based on a
Orion Absolute Navigation System Progress and Challenges
Holt, Greg N.; D'Souza, Christopher
2011-01-01
The Orion spacecraft is being designed as NASA's next-generation exploration vehicle for crewed missions beyond Low-Earth Orbit. The navigation system for the Orion spacecraft is being designed in a Multi-Organizational Design Environment (MODE) team including contractor and NASA personnel. The system uses an Extended Kalman Filter to process measurements and determine the state. The design of the navigation system has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudorange and deltarange, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, pad alignment, cold start are discussed as are
Vision enhanced navigation for unmanned systems
Wampler, Brandon Loy
A vision based simultaneous localization and mapping (SLAM) algorithm is evaluated for use on unmanned systems. SLAM is a technique used by a vehicle to build a map of an environment while concurrently keeping track of its location within the map, without a priori knowledge. The work in this thesis is focused on using SLAM as a navigation solution when global positioning system (GPS) service is degraded or temporarily unavailable. Previous work on unmanned systems that lead up to the determination that a better navigation solution than GPS alone is first presented. This previous work includes control of unmanned systems, simulation, and unmanned vehicle hardware testing. The proposed SLAM algorithm follows the work originally developed by Davidson et al. in which they dub their algorithm MonoSLAM [1--4]. A new approach using the Pyramidal Lucas-Kanade feature tracking algorithm from Intel's OpenCV (open computer vision) library is presented as a means of keeping correct landmark correspondences as the vehicle moves through the scene. Though this landmark tracking method is unusable for long term SLAM due to its inability to recognize revisited landmarks, as opposed to the Scale Invariant Feature Transform (SIFT) and Speeded Up Robust Features (SURF), its computational efficiency makes it a good candidate for short term navigation between GPS position updates. Additional sensor information is then considered by fusing INS and GPS information into the SLAM filter. The SLAM system, in its vision only and vision/IMU form, is tested on a table top, in an open room, and finally in an outdoor environment. For the outdoor environment, a form of the slam algorithm that fuses vision, IMU, and GPS information is tested. The proposed SLAM algorithm, and its several forms, are implemented in C++ using an Extended Kalman Filter (EKF). Experiments utilizing a live video feed from a webcam are performed. The different forms of the filter are compared and conclusions are made on
Representing User Navigation in XML Retrieval with Structural Summaries
Ali, M. S.; Consens, Mariano P.; Larsen, Birger
This poster presents a novel way to represent user navigation in XML retrieval using collection statistics from XML summaries. Currently, developing user navigation models in XML retrieval is costly and the models are specific to collected user assessments. We address this problem by proposing...
Navigating across Cultures: Narrative Constructions of Lived Experience
Pufall-Jones, Elizabeth; Mistry, Jayanthi
2010-01-01
In this study, we investigated how individuals from diverse backgrounds learn to navigate the many worlds in which they live and explore how variations in life experiences are associated with aspects of navigating across cultures. We conducted the study using a phenomenological approach based on retrospective personal narratives from 19 young…
Environmental layout complexity affects neural activity during navigation in humans.
Slone, Edward; Burles, Ford; Iaria, Giuseppe
2016-05-01
Navigating large-scale surroundings is a fundamental ability. In humans, it is commonly assumed that navigational performance is affected by individual differences, such as age, sex, and cognitive strategies adopted for orientation. We recently showed that the layout of the environment itself also influences how well people are able to find their way within it, yet it remains unclear whether differences in environmental complexity are associated with changes in brain activity during navigation. We used functional magnetic resonance imaging to investigate how the brain responds to a change in environmental complexity by asking participants to perform a navigation task in two large-scale virtual environments that differed solely in interconnection density, a measure of complexity defined as the average number of directional choices at decision points. The results showed that navigation in the simpler, less interconnected environment was faster and more accurate relative to the complex environment, and such performance was associated with increased activity in a number of brain areas (i.e. precuneus, retrosplenial cortex, and hippocampus) known to be involved in mental imagery, navigation, and memory. These findings provide novel evidence that environmental complexity not only affects navigational behaviour, but also modulates activity in brain regions that are important for successful orientation and navigation. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
The impact of navigation systems on traffic safety
Rooijen, T. van; Vonk, T.
2007-01-01
This paper studies the impact of navigation systems on traffic safety in the Netherlands. This study consists of four analyses: a literature survey, a database analysis, a user survey and an instrumented vehicle study. The results of the four sections show that navigation systems have a positive
The impact of navigation systems on traffic safety
Rooijen, T. van; Vonk, T.
2008-01-01
This paper studies the impact of navigation systems on traffic safety in the Netherlands. This study consists of four analyses: a literature survey, a database analysis, a user survey and an instrumented vehicle study. The results of the four sections show that navigation systems have a positive
A Qualitative Approach to Mobile Robot Navigation Using RFID
Hossain, M; Rashid, M M; Bhuiyan, M M I; Ahmed, S; Akhtaruzzaman, M
2013-01-01
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
Collective navigation of complex networks: Participatory greedy routing.
Kleineberg, Kaj-Kolja; Helbing, Dirk
2017-06-06
Many networks are used to transfer information or goods, in other words, they are navigated. The larger the network, the more difficult it is to navigate efficiently. Indeed, information routing in the Internet faces serious scalability problems due to its rapid growth, recently accelerated by the rise of the Internet of Things. Large networks like the Internet can be navigated efficiently if nodes, or agents, actively forward information based on hidden maps underlying these systems. However, in reality most agents will deny to forward messages, which has a cost, and navigation is impossible. Can we design appropriate incentives that lead to participation and global navigability? Here, we present an evolutionary game where agents share the value generated by successful delivery of information or goods. We show that global navigability can emerge, but its complete breakdown is possible as well. Furthermore, we show that the system tends to self-organize into local clusters of agents who participate in the navigation. This organizational principle can be exploited to favor the emergence of global navigability in the system.
GNSS-based receiver autonomous integrity monitoring for aircraft navigation
Imparato, D.
2016-01-01
Nowadays, GNSS-based navigation is moving more and more to critical applications. Global Navigation Satellite Systems (GNSS), which in the past used to be represented by the American GPS and the Russian GLONASS are now growing in number and performance. The European systemGalileo and the Chinese
Remarks on the observability of single beacon underwater navigation
Jouffroy, Jerome; Ross, Andrew
This paper contributes a simple and intuitive result in the analysis of underwater navigation using a single ranging beacon. This analysis should help with the design of small and lightweight underwater vehicles by reducing the amount of instrumentation required for accurate navigation. The concept...
Distributed Cognition in Ship Navigation and Prevention of Collision
Koester, Thomas; Hyll, Nikolaj; Stage, Jan
2009-01-01
In this paper we investigate how technology can help the navigator to a better performance. We use three examples based on observations onboard three ships to show, how technology can support the work of the navigator and thereby enhance the performance. Our analysis is based on the paradigm...
Comparative advantage between traditional and smart navigation systems
Shin, Jeongkyu; Kim, Pan-Jun; Kim, Seunghwan
2013-03-01
The smart navigation system that refers to real-time traffic data is believed to be superior to traditional navigation systems. To verify this belief, we created an agent-based traffic model and examined the effect of changing market share of the traditional shortest-travel-time algorithm based navigation and the smart navigation system. We tested our model on the grid and actual metropolitan road network structures. The result reveals that the traditional navigation system have better performance than the smart one as the market share of the smart navigation system exceeds a critical value, which is contrary to conventional expectation. We suggest that the superiority inversion between agent groups is strongly related to the traffic weight function form, and is general. We also found that the relationship of market share, traffic flow density and travel time is determined by the combination of congestion avoidance behavior of the smartly navigated agents and the inefficiency of shortest-travel-time based navigated agents. Our results can be interpreted with the minority game and extended to the diverse topics of opinion dynamics. This work was supported by the Original Technology Research Program for Brain Science through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology(No. 2010-0018847).