Discrete Mathematics in the Schools. DIMACS Series in Discrete Mathematics and Theoretical Computer Science, Volume 36.
ERIC Educational Resources Information Center
Rosenstein, Joseph G., Ed.; Franzblau, Deborah S., Ed.; Roberts, Fred S., Ed.
This book is a collection of articles by experienced educators and explains why and how discrete mathematics should be taught in K12 classrooms. It includes evidence for "why" and practical guidance for "how" and also discusses how discrete mathematics can be used as a vehicle for achieving the broader goals of the major effort now underway to…
Helping General Physical Educators and Adapted Physical Educators Address the Office of Civil Rights Dear Colleague Guidance Letter: Part IIIPractitioners and Programs
ERIC Educational Resources Information Center
Poulin, David; Martinez, David; Aenchbacher, Amy; Aiello, Rocco; Doyle, Mike; Hilgenbrinck, Linda; Busse, Sean; Cappuccio, Jim
20130101
In Part III of the feature, physical educators and adapted physical educators offer current best practices as models of implementation for readers. Contributions included are: (1) Answer to the Dear Colleague Letter from the Anchorage School District's Adapted Sport Program (David Poulin); (2) Georgia's Adapted Physical Educators…
Discrete resonances
NASA Astrophysics Data System (ADS)
Vivaldi, Franco
20151201
The concept of resonance has been instrumental to the study of Hamiltonian systems with divided phase space. One can also define such systems over discrete spaces, which have a finite or countable number of points, but in this new setting the notion of resonance must be reconsidered from scratch. I review some recent developments in the area of arithmetic dynamics which outline some salient features of linear and nonlinear stable (elliptic) orbits over a discrete space, and also underline the difficulties that emerge in their analysis.

Discrete resonances
NASA Astrophysics Data System (ADS)
Vivaldi, Franco
The concept of resonance has been instrumental to the study of Hamiltonian systems with divided phase space. One can also define such systems over discrete spaces, which have a finite or countable number of points, but in this new setting the notion of resonance must be reconsidered from scratch. I review some recent developments in the area of arithmetic dynamics which outline some salient features of linear and nonlinear stable (elliptic) orbits over a discrete space, and also underline the difficulties that emerge in their analysis.

Observers for discretetime nonlinear systems
NASA Astrophysics Data System (ADS)
Grossman, Walter D.
Observer synthesis for discretetime nonlinear systems with special applications to parameter estimation is analyzed. Two new types of observers are developed. The first new observer is an adaptation of the Friedland continuoustime parameter estimator to discretetime systems. The second observer is an adaptation of the continuoustime Gauthier observer to discretetime systems. By adapting these observers to discretetime continuoustime parameter estimation problems which were formerly intractable become tractable. In addition to the two newly developed observers, two observers already described in the literature are analyzed and deficiencies with respect to noise rejection are demonstrated. Improved versions of these observers are proposed and their performance demonstrated. The issues of discretetime observability, discretetime system inversion, and optimal probing are also addressed.

Adapting Data Processing To Compare Model and Experiment Accurately: A Discrete Element Model and Magnetic Resonance Measurements of a 3D Cylindrical Fluidized Bed.
PubMed
Boyce, Christopher M; Holland, Daniel J; Scott, Stuart A; Dennis, John S
20131218
Discrete element modeling is being used increasingly to simulate flow in fluidized beds. These models require complex measurement techniques to provide validation for the approximations inherent in the model. This paper introduces the idea of modeling the experiment to ensure that the validation is accurate. Specifically, a 3D, cylindrical gasfluidized bed was simulated using a discrete element model (DEM) for particle motion coupled with computational fluid dynamics (CFD) to describe the flow of gas. The results for timeaveraged, axial velocity during bubbling fluidization were compared with those from magnetic resonance (MR) experiments made on the bed. The DEMCFD data were postprocessed with various methods to produce timeaveraged velocity maps for comparison with the MR results, including a method which closely matched the pulse sequence and data processing procedure used in the MR experiments. The DEMCFD results processed with the MRtype timeaveraging closely matched experimental MR results, validating the DEMCFD model. Analysis of different averaging procedures confirmed that MR timeaverages of dynamic systems correspond to particleweighted averaging, rather than frameweighted averaging, and also demonstrated that the use of Gaussian slices in MR imaging of dynamic systems is valid. PMID:24478537

Adapting Data Processing To Compare Model and Experiment Accurately: A Discrete Element Model and Magnetic Resonance Measurements of a 3D Cylindrical Fluidized Bed
PubMed Central
20130101
Discrete element modeling is being used increasingly to simulate flow in fluidized beds. These models require complex measurement techniques to provide validation for the approximations inherent in the model. This paper introduces the idea of modeling the experiment to ensure that the validation is accurate. Specifically, a 3D, cylindrical gasfluidized bed was simulated using a discrete element model (DEM) for particle motion coupled with computational fluid dynamics (CFD) to describe the flow of gas. The results for timeaveraged, axial velocity during bubbling fluidization were compared with those from magnetic resonance (MR) experiments made on the bed. The DEMCFD data were postprocessed with various methods to produce timeaveraged velocity maps for comparison with the MR results, including a method which closely matched the pulse sequence and data processing procedure used in the MR experiments. The DEMCFD results processed with the MRtype timeaveraging closely matched experimental MR results, validating the DEMCFD model. Analysis of different averaging procedures confirmed that MR timeaverages of dynamic systems correspond to particleweighted averaging, rather than frameweighted averaging, and also demonstrated that the use of Gaussian slices in MR imaging of dynamic systems is valid. PMID:24478537

Collective cell migration: guidance principles and hierarchies.
PubMed
Haeger, Anna; Wolf, Katarina; Zegers, Mirjam M; Friedl, Peter
20150901
Collective cell migration results from the establishment and maintenance of collective polarization, mechanocoupling, and cytoskeletal kinetics. The guidance of collective cell migration depends on a reciprocal process between cellintrinsic multicellular organization with leaderfollower cell behavior and results in mechanosensory integration of extracellular guidance cues. Important guidance mechanisms include chemotaxis, haptotaxis, durotaxis, and straininduced mechanosensing to move cell groups along interfaces and paths of least resistance. Additional guidance mechanisms steering cell groups during specialized conditions comprise electrotaxis and passive drift. To form higherorder cell and tissue structures during morphogenesis and cancer invasion, these guidance principles act in parallel and are integrated for collective adaptation to and shaping of varying tissue environments. We review mechanochemical and electrical inputs and multiparameter signal integration underlying collective guidance, decision making, and outcome. PMID:26137890

Space shuttle guidance, navigation, and control design equations. Volume 3: Guidance
NASA Technical Reports Server (NTRS)
19730101
Space shuttle guidance, navigation, and control design equations are presented. The spaceshuttle mission includes three relatively distinct guidance phases which are discussed; atmospheric boost, which is characterized by an adaptive guidance law; extraatmospheric activities; and reentry activities, where aerodynamic surfaces are the principal effectors. Guidance tasks include premaneuver targeting and powered flight guidance, where powered flight is defined to include the application of aerodynamic forces as well as thruster forces. A flow chart which follows guidance activities throughout the mission from the prelaunch phase through touchdown is presented. The main guidance programs and subroutines used in each phase of a typical rendezvous mission are listed. Detailed software requirements are also presented.

Autonomous Guidance, Navigation and Control
NASA Technical Reports Server (NTRS)
Bordano, A. J.; Mcswain, G. G.; Fernandes, S. T.
19910101
The NASA Autonomous Guidance, Navigation and Control (GN&C) Bridging program is reviewed to demonstrate the program plan and GN&C systems for the Space Shuttle. The ascent CN&C system is described in terms of elements such as the generalpurpose digital computers, sensors for the navigation subsystem, the guidancesystem software, and the flightcontrol subsystem. Balloonbased and lidar wind soundings are used for operations assessment on the day of launch, and the guidance software is based on dedicated units for atmospheric powered flight, vacuum powered flight, and abortspecific situations. Optimization of the flight trajectories is discussed, and flightcontrol responses are illustrated for wavelengths of 5006000 m. Alternate sensors are used for load relief, and adaptive GN&C systems based on alternate gain synthesis are used for systems failures.

A WENOsolver combined with adaptive momentum discretization for the Wigner transport equation and its application to resonant tunneling diodes
PubMed Central
Dorda, Antonius; Schürrer, Ferdinand
20150101
We present a novel numerical scheme for the deterministic solution of the Wigner transport equation, especially suited to deal with situations in which strong quantum effects are present. The unique feature of the algorithm is the expansion of the Wigner function in local basis functions, similar to finite element or finite volume methods. This procedure yields a discretization of the pseudodifferential operator that conserves the particle density on arbitrarily chosen grids. The high flexibility in refining the grid spacing together with the weighted essentially nonoscillatory (WENO) scheme for the advection term allows for an accurate and wellresolved simulation of the phase space dynamics. A resonant tunneling diode is considered as test case and a detailed convergence study is given by comparing the results to a nonequilibrium Green's functions calculation. The impact of the considered domain size and of the grid spacing is analyzed. The obtained convergence of the results towards a quasiexact agreement of the steady state Wigner and Green's functions computations demonstrates the accuracy of the scheme, as well as the high flexibility to adjust to different physical situations. PMID:25892748

A WENOsolver combined with adaptive momentum discretization for the Wigner transport equation and its application to resonant tunneling diodes
SciTech Connect
Dorda, Antonius Schürrer, Ferdinand
20150301
We present a novel numerical scheme for the deterministic solution of the Wigner transport equation, especially suited to deal with situations in which strong quantum effects are present. The unique feature of the algorithm is the expansion of the Wigner function in local basis functions, similar to finite element or finite volume methods. This procedure yields a discretization of the pseudodifferential operator that conserves the particle density on arbitrarily chosen grids. The high flexibility in refining the grid spacing together with the weighted essentially nonoscillatory (WENO) scheme for the advection term allows for an accurate and wellresolved simulation of the phase space dynamics. A resonant tunneling diode is considered as test case and a detailed convergence study is given by comparing the results to a nonequilibrium Green's functions calculation. The impact of the considered domain size and of the grid spacing is analyzed. The obtained convergence of the results towards a quasiexact agreement of the steady state Wigner and Green's functions computations demonstrates the accuracy of the scheme, as well as the high flexibility to adjust to different physical situations.

On the design of fuzzified trajectory shaping guidance law.
PubMed
Lin, ChunLiang; Lin, YuPing; Chen, KaiMing
20090401
Midcourse guidance is commonly designed to save as much energy as possible so that the missile's final speed can be maximized while entering the homing stage. For this purpose, a competitive guidance design should be able to generate an admissible flight trajectory as to bring the interceptor to a superior altitude for a favorable target engagement. In this paper, a new adaptive trajectory shaping guidance scheme based on the adaptive fuzzy inference system, which is capable of generating a variety of trajectories for efficient target interception, is presented. The guidance law is developed with the aim of saving the interceptor's energy conservation while improving performance robustness. Applications of the presented approach have included a variety of mission oriented guidance, such as cruise missile guidance, antiballistic missile guidance, etc. PMID:19054508

Some Thoughts as Educational Guidance in Colombia Faces the Twentyfirst Century.
ERIC Educational Resources Information Center
Super, Donald E.
19840101
The author shares his views concerning furthering the development of educational and vocational guidance services in developing countries. He discusses the importance of society, the family, and the individual; guidance philosophy; cultural compatibility of guidance and counseling; and guidance adaptations and their objectives. (CT)

Discrete Trials Teaching
ERIC Educational Resources Information Center
Ghezzi, Patrick M.
20070101
The advantages of emphasizing discrete trials "teaching" over discrete trials "training" are presented first, followed by a discussion of discrete trials as a method of teaching that emerged historicallyand as a matter of necessity for difficult learners such as those with autismfrom discrete trials as a method for laboratory research. The…

Elementary School Guidance Bibliography.
ERIC Educational Resources Information Center
Biasco, Frank
This bibliography lists articles and books dealing with elementary school guidance. The bibliography is arranged alphabetically by author. No annotations are given. Approximately 70 titles are given, covering most phases of elementary guidance. (KJ)

DOE Waste Treatability Group Guidance
SciTech Connect
Kirkpatrick, T.D.
19950101
This guidance presents a method and definitions for aggregating U.S. Department of Energy (DOE) waste into streams and treatability groups based on characteristic parameters that influence waste management technology needs. Adaptable to all DOE waste types (i.e., radioactive waste, hazardous waste, mixed waste, sanitary waste), the guidance establishes categories and definitions that reflect variations within the radiological, matrix (e.g., bulk physical/chemical form), and regulated contaminant characteristics of DOE waste. Beginning at the waste container level, the guidance presents a logical approach to implementing the characteristic parameter categories as part of the basis for defining waste streams and as the sole basis for assigning streams to treatability groups. Implementation of this guidance at each DOE site will facilitate the development of technically defined, sitespecific waste stream data sets to support waste management planning and reporting activities. Consistent implementation at all of the sites will enable aggregation of the sitespecific waste stream data sets into comparable national data sets to support these activities at a DOE complexwide level.

Unified powered flight guidance
NASA Technical Reports Server (NTRS)
Brand, T. J.; Brown, D. W.; Higgins, J. P.
19730101
A complete revision of the orbiter powered flight guidance scheme is presented. A unified approach to powered flight guidance was taken to accommodate all phases of exoatmospheric orbiter powered flight, from ascent through deorbit. The guidance scheme was changed from the previous modified version of the Lambert Aim Point Maneuver Mode used in Apollo to one that employs linear tangent guidance concepts. This document replaces the previous ascent phase equation document.

A neural net approach to space vehicle guidance
NASA Technical Reports Server (NTRS)
Caglayan, Alper K.; Allen, Scott M.
19900101
The space vehicle guidance problem is formulated using a neural network approach, and the appropriate neural net architecture for modeling optimum guidance trajectories is investigated. In particular, an investigation is made of the incorporation of prior knowledge about the characteristics of the optimal guidance solution into the neural network architecture. The online classification performance of the developed network is demonstrated using a synthesized network trained with a database of optimum guidance trajectories. Such a neuralnetworkbased guidance approach can readily adapt to environment uncertainties such as those encountered by an AOTV during atmospheric maneuvers.

Apollo experience report guidance and control systems: Primary guidance, navigation, and control system development
NASA Technical Reports Server (NTRS)
Holley, M. D.; Swingle, W. L.; Bachman, S. L.; Leblanc, C. J.; Howard, H. T.; Biggs, H. M.
19760101
The primary guidance, navigation, and control systems for both the lunar module and the command module are described. Development of the Apollo primary guidance systems is traced from adaptation of the Polaris Mark II system through evolution from Block I to Block II configurations; the discussion includes design concepts used, test and qualification programs performed, and major problems encountered. The major subsystems (inertial, computer, and optical) are covered. Separate sections on the inertial components (gyroscopes and accelerometers) are presented because these components represent a major contribution to the success of the primary guidance, navigation, and control system.

Principles of Discrete Time Mechanics
NASA Astrophysics Data System (ADS)
Jaroszkiewicz, George
20140401
1. Introduction; 2. The physics of discreteness; 3. The road to calculus; 4. Temporal discretization; 5. Discrete time dynamics architecture; 6. Some models; 7. Classical cellular automata; 8. The action sum; 9. Worked examples; 10. Lee's approach to discrete time mechanics; 11. Elliptic billiards; 12. The construction of system functions; 13. The classical discrete time oscillator; 14. Type 2 temporal discretization; 15. Intermission; 16. Discrete time quantum mechanics; 17. The quantized discrete time oscillator; 18. Path integrals; 19. Quantum encoding; 20. Discrete time classical field equations; 21. The discrete time Schrodinger equation; 22. The discrete time KleinGordon equation; 23. The discrete time Dirac equation; 24. Discrete time Maxwell's equations; 25. The discrete time Skyrme model; 26. Discrete time quantum field theory; 27. Interacting discrete time scalar fields; 28. Space, time and gravitation; 29. Causality and observation; 30. Concluding remarks; Appendix A. Coherent states; Appendix B. The timedependent oscillator; Appendix C. Quaternions; Appendix D. Quantum registers; References; Index.

NoReference Image Blur Assessment Based on Discrete Orthogonal Moments.
PubMed
Li, Leida; Lin, Weisi; Wang, Xuesong; Yang, Gaobo; Bahrami, Khosro; Kot, Alex C
20160101
Blur is a key determinant in the perception of image quality. Generally, blur causes spread of edges, which leads to shape changes in images. Discrete orthogonal moments have been widely studied as effective shape descriptors. Intuitively, blur can be represented using discrete moments since noticeable blur affects the magnitudes of moments of an image. With this consideration, this paper presents a blind image blur evaluation algorithm based on discrete Tchebichef moments. The gradient of a blurred image is first computed to account for the shape, which is more effective for blur representation. Then the gradient image is divided into equalsize blocks and the Tchebichef moments are calculated to characterize image shape. The energy of a block is computed as the sum of squared nonDC moment values. Finally, the proposed image blur score is defined as the variancenormalized moment energy, which is computed with the guidance of a visual saliency model to adapt to the characteristic of human visual system. The performance of the proposed method is evaluated on four public image quality databases. The experimental results demonstrate that our method can produce blur scores highly consistent with subjective evaluations. It also outperforms the stateoftheart image blur metrics and several generalpurpose noreference quality metrics. PMID:25647763

Stressor Identification Guidance Document
EPA Science Inventory
EPA has made availabile the Stressor Identification Guidance Document (EPA 822B00025) published under the authority of Section 304(a)(2) of the Clean Water Act (CWA). This technical guidance doc...

Aiding Vertical Guidance Understanding
NASA Technical Reports Server (NTRS)
Feary, Michael; McCrobie, Daniel; Alkin, Martin; Sherry, Lance; Polson, Peter; Palmer, Everett; McQuinn, Noreen
19980101
A twopart study was conducted to evaluate modern flight deck automation and interfaces. In the first part, a survey was performed to validate the existence of automation surprises with current pilots. Results indicated that pilots were often surprised by the behavior of the automation. There were several surprises that were reported more frequently than others. An experimental study was then performed to evaluate (1) the reduction of automation surprises through training specifically for the vertical guidance logic, and (2) a new display that describes the flight guidance in terms of aircraft behaviors instead of control modes. The study was performed in a simulator that was used to run a complete flight with actual airline pilots. Three groups were used to evaluate the guidance display and training. In the training, condition, participants went through a training program for vertical guidance before flying the simulation. In the display condition, participants ran through the same training program and then flew the experimental scenario with the new GuidanceFlight Mode Annunciator (GFMA). Results showed improved pilot performance when given training specifically for the vertical guidance logic and greater improvements when given the training and the new GFMA. Using actual behavior of the avionics to design pilot training and FMA is feasible, and when the automated vertical guidance mode of the Flight Management System is engaged, the display of the guidance mode and targets yields improved pilot performance.

Evaluating Guidance Activities.
ERIC Educational Resources Information Center
Sanborn, Marshall P.
This report discusses one of the consistent problems in school counseling and guidancethat of furnishing concrete evidence concerning the effects of counseling and guidance activities on the development of children. The following causal factors are discussed: (1) the difficulty of pinning down abstractly stated goals in an operational manner at…

Corporate information management guidance
SciTech Connect
19970801
At the request of the Department of Energy`s (DOE) Information Management (IM) Council, IM representatives from nearly all Headquarters (HQ) organizations have been meeting over the past year as the Corporate Guidance Group (CGG) to develop useful and sound corporate information management (IM) guidance. The ability of the Department`s IM community to develop such unified guidance continues to be critical to the success of future Departmental IM planning processes and the establishment of a wellcoordinated IM environment between Headquarters and field organizations. This report, with 26 specific corporate IM guidance items documented and unanimously agreed to, as well as 12 items recommended for further development and 3 items deferred for future consideration, represents a highly successful effort by the IM community. The effort has proven that the diverse DOE organizations can put aside individual preferences and work together towards a common and mutually beneficial goal. In examining most areas and issues associated with information management in the Department, they have developed specific, farreaching, and useful guidance. The IM representatives recommend that the documented guidance items provided in this report and approved by the DOE IM Council be followed by all IM organizations. The representatives also strongly recommend that the guidance process developed by the CGG be the single process for developing corporate IM guidance.

Ascent Guidance Comparisons
NASA Technical Reports Server (NTRS)
Hanson, John M.; Shrader, M. Wade; Cruzen, Craig A.
19950101
This paper contains results from ascent guidance studies conducted at the NASA Marshall Space Flight Center. The studies include investigation of different guidance schemes for a variety of potential launch vehicles. Criteria of a successful ascent guidance scheme are low operations cost, satisfaction of load indicator constraints, and maximization of performance. Results show that openloop designs as a function of altitude or velocity are preferable to designs that are functions of time. Optimized openloop trajectories can increase performance while maintaining load indicators within limits. Closedloop atmospheric schemes that involve linear tangent steering or feedback of velocity terms for trajectory modification did not yield any improvement. Early release of vacuum closedloop guidance, including use during solid rocket booster operation, yields some improvements. Evaluation of a closedloop optimization scheme for flying through the atmosphere shows no advantages over openloop optimization. Dispersion study results for several potential guidance schemes and launch vehicles are included in the paper and are not a discriminator between guidance schemes. The primary cost driver is mission operations philosophy, not choice of guidance scheme. More autonomous guidance schemes can help in movement towards a philosophy that would reduce operations costs.

Guidance for Total Development.
ERIC Educational Resources Information Center
Van Hoose, William H.
Elementary guidance, deriving much of its content from the developmental phenomena of middle childhood, is viewed as the maximization of human potentiality in the total range of the population. Included in the list of elementary school guidance objectives are (1) aiding academic development, (2) helping children develop health selfconcepts, (3)…

Shuttle entry guidance revisited
NASA Technical Reports Server (NTRS)
Mease, Kenneth D.; Kremer, JeanPaul
19920101
The Shuttle entry guidance concept is reviewed which is aimed at tracking a reference drag trajectory that leads to the specified range and velocity for the initiation of the terminal energy management phase. An approximate method of constructing the domain of attraction is proposed, and its validity is ascertained by simulation. An alternative guidance law yielding global exponential tracking in the absence of control saturation is derived using a feedback linearization method. It is noted that the alternative guidance law does not improve on the stability and performance of the current guidance law, for the operating domain and control capability of the Shuttle. It is suggested that the new guidance law with a larger operating domain and increased lifttodrag capability would be superior.

Shuttle entry guidance
NASA Technical Reports Server (NTRS)
Harpold, J. C.; Graves, C. A., Jr.
19780101
This paper describes the design of the entry guidance for the Space Shuttle Orbiter. This guidance provides the steering commands for trajectory control from initial penetration of the earth's atmosphere until the terminal area guidance is activated at an earthrelative speed of 2500 fps. At this point, the Orbiter is at a distance of about 50 nmi from the runway threshold, and at an altitude of about 80,000 ft. The entry guidance design is based on an analytic solution of the equations of motion defining the drag acceleration profile that meets the terminal criteria of the entry flight while maintaining the flight within systems and operational constraints. Guidance commands, which are based on a control law that ensures damping of oscillatory type trajectory motion, are computed to steer the Orbiter to this drag acceleration profile.

Discrete ordinates methods in xy geometry with spatially varying angular discretization
SciTech Connect
Bal, G.; Warin, X.
19971001
The efficiency of a new quadrature rule adapted to the numerical resolution of a neutron transport problem in xy geometry is presented based on the use of the discrete ordinates method for the angular variable. The purpose of introducing this quadrature rule is to couple two different angular discretizations used on two nonoverlapping subdomains, which is useful for performing local refinement. This coupling and some numerical results of source problems are presented.

Discrete Element Modeling
SciTech Connect
Morris, J; Johnson, S
20071203
The Distinct Element Method (also frequently referred to as the Discrete Element Method) (DEM) is a Lagrangian numerical technique where the computational domain consists of discrete solid elements which interact via compliant contacts. This can be contrasted with Finite Element Methods where the computational domain is assumed to represent a continuum (although many modern implementations of the FEM can accommodate some Distinct Element capabilities). Often the terms Discrete Element Method and Distinct Element Method are used interchangeably in the literature, although Cundall and Hart (1992) suggested that Discrete Element Methods should be a more inclusive term covering Distinct Element Methods, Displacement Discontinuity Analysis and Modal Methods. In this work, DEM specifically refers to the Distinct Element Method, where the discrete elements interact via compliant contacts, in contrast with Displacement Discontinuity Analysis where the contacts are rigid and all compliance is taken up by the adjacent intact material.

Synchronous Discrete Harmonic Oscillator
SciTech Connect
Antippa, Adel F.; Dubois, Daniel M.
20081017
We introduce the synchronous discrete harmonic oscillator, and present an analytical, numerical and graphical study of its characteristics. The oscillator is synchronous when the time T for one revolution covering an angle of 2{pi} in phase space, is an integral multiple N of the discrete time step {delta}t. It is fully synchronous when N is even. It is pseudosynchronous when T/{delta}t is rational. In the energy conserving hyperincursive representation, the phase space trajectories are perfectly stable at all time scales, and in both synchronous and pseudosynchronous modes they cycle through a finite number of phase space points. Consequently, both the synchronous and the pseudosynchronous hyperincursive modes of timediscretization provide a physically realistic and mathematically coherent, procedure for dynamic, background independent, discretization of spacetime. The procedure is applicable to any stable periodic dynamical system, and provokes an intrinsic correlation between space and time, whereby spacediscretization is a direct consequence of backgroundindependent timediscretization. Hence, synchronous discretization moves the formalism of classical mechanics towards that of special relativity. The frequency of the hyperincursive discrete harmonic oscillator is ''blue shifted'' relative to its continuum counterpart. The frequency shift has the precise value needed to make the speed of the system point in phase space independent of the discretizing time interval {delta}t. That is the speed of the system point is the same on the polygonal (in the discrete case) and the circular (in the continuum case) phase space trajectories.

Aerocapture Guidance Algorithm Comparison Campaign
NASA Technical Reports Server (NTRS)
Rousseau, Stephane; Perot, Etienne; Graves, Claude; Masciarelli, James P.; Queen, Eric
20020101
The aerocapture is a promising technique for the future human interplanetary missions. The Mars Sample Return was initially based on an insertion by aerocapture. A CNES orbiter Mars Premier was developed to demonstrate this concept. Mainly due to budget constraints, the aerocapture was cancelled for the French orbiter. A lot of studies were achieved during the three last years to develop and test different guidance algorithms (APC, EC, TPC, NPC). This work was shared between CNES and NASA, with a fruitful joint working group. To finish this study an evaluation campaign has been performed to test the different algorithms. The objective was to assess the robustness, accuracy, capability to limit the load, and the complexity of each algorithm. A simulation campaign has been specified and performed by CNES, with a similar activity on the NASA side to confirm the CNES results. This evaluation has demonstrated that the numerical guidance principal is not competitive compared to the analytical concepts. All the other algorithms are well adapted to guaranty the success of the aerocapture. The TPC appears to be the more robust, the APC the more accurate, and the EC appears to be a good compromise.

Discrete monotron oscillator
SciTech Connect
Carlsten, B.E.; Haynes, W.B.
19960801
The authors theoretically and numerically investigate the operation and behavior of the discrete monotron oscillator, a novel highpower microwave source. The discrete monotron differs from conventional monotrons and transit time oscillators by shielding the electron beam from the monotron cavity`s RF fields except at two distinct locations. This makes the discrete monotron act more like a klystron than a distributed traveling wave device. As a result, the oscillator has higher efficiency and can operate with higher beam powers than other single cavity oscillators and has more stable operation without requiring a seed input signal than mildly relativistic, intensebeam klystron oscillators.

Comprehensive Guidance Programs That Work.
ERIC Educational Resources Information Center
Gysbers, Norman C.; And Others
This monograph describes how the comprehensive guidance model is transforming elementarysecondary school guidance and counseling programs in schools across the country. It incorporates the ideas and experiences of 12 guidance program developers in the actual use of the comprehensive guidance model in diverse school and cultural settings. The book…

Video guidance, landing, and imaging systems
NASA Technical Reports Server (NTRS)
Schappell, R. T.; Knickerbocker, R. L.; Tietz, J. C.; Grant, C.; Rice, R. B.; Moog, R. D.
19750101
The adaptive potential of video guidance technology for earth orbital and interplanetary missions was explored. The application of video acquisition, pointing, tracking, and navigation technology was considered to three primary missions: planetary landing, earth resources satellite, and spacecraft rendezvous and docking. It was found that an imaging system can be mechanized to provide a spacecraft or satellite with a considerable amount of adaptability with respect to its environment. It also provides a level of autonomy essential to many future missions and enhances their data gathering ability. The feasibility of an autonomous video guidance system capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was successfully demonstrated in the laboratory. The techniques developed for acquisition, pointing, and tracking show promise for recognizing and tracking coastlines, rivers, and other constituents of interest. Routines were written and checked for rendezvous, docking, and stationkeeping functions.

Correcting for VisuoHaptic Biases in 3D Haptic Guidance
PubMed Central
Kuling, Irene A.; Brenner, Eli; Bergmann Tiest, Wouter M.; Kappers, Astrid M. L.
20160101
Visuohaptic biases are observed when bringing your unseen hand to a visual target. The biases are different between, but consistent within participants. We investigated the usefulness of adjusting haptic guidance to these userspecific biases in aligning haptic and visual perception. By adjusting haptic guidance according to the biases, we aimed to reduce the conflict between the modalities. We first measured the biases using an adaptive procedure. Next, we measured performance in a pointing task using three conditions: 1) visual images that were adjusted to userspecific biases, without haptic guidance, 2) veridical visual images combined with haptic guidance, and 3) shifted visual images combined with haptic guidance. Adding haptic guidance increased precision. Combining haptic guidance with userspecific visual information yielded the highest accuracy and the lowest level of conflict with the guidance at the end point. These results show the potential of correcting for userspecific perceptual biases when designing haptic guidance. PMID:27438009

The Discrete Hanging Cable
ERIC Educational Resources Information Center
Peters, James V.
20040101
Using the methods of finite difference equations the discrete analogue of the parabolic and catenary cable are analysed. The fibonacci numbers and the golden ratio arise in the treatment of the catenary.

Discretizations of axisymmetric systems
NASA Astrophysics Data System (ADS)
Frauendiener, Jörg
20021101
In this paper we discuss stability properties of various discretizations for axisymmetric systems including the socalled cartoon method which was proposed by Alcubierre et al. for the simulation of such systems on Cartesian grids. We show that within the context of the method of lines such discretizations tend to be unstable unless one takes care in the way individual singular terms are treated. Examples are given for the linear axisymmetric wave equation in flat space.

Vocational Guidance and the Labour Market: Guidance to Transform or Guidance to Domesticate?
ERIC Educational Resources Information Center
Kann, Ulla
19880101
Explores the conflict in guidance arising from the desire to consider the needs of society while guaranteeing individual freedom of choice. Discusses the theoretical basis of vocational guidance. Gives examples of "domestication" and "transformation" approaches to guidance and discusses the consequences of viewing guidance as a change strategy.(KO)

Exploring Goals. Career Guidance.
ERIC Educational Resources Information Center
Mesa Public Schools, AZ.
Materials contained in this career guidance unit are designed to enable senior high school students to relate their abilities scores from the Developed Abilities Performance (DAP) instrument to actual vocational areas and Long Range [occupational] Goals (LRG) for later indepth study. The length of the unit is six 55minute periods. Instructional…

Regulatory guidance document
SciTech Connect
19940501
The Office of Civilian Radioactive Waste Management (OCRWM) Program Management System Manual requires preparation of the OCRWM Regulatory Guidance Document (RGD) that addresses licensing, environmental compliance, and safety and health compliance. The document provides: regulatory compliance policy; guidance to OCRWM organizational elements to ensure a consistent approach when complying with regulatory requirements; strategies to achieve policy objectives; organizational responsibilities for regulatory compliance; guidance with regard to Program compliance oversight; and guidance on the contents of a projectlevel Regulatory Compliance Plan. The scope of the RGD includes site suitability evaluation, licensing, environmental compliance, and safety and health compliance, in accordance with the direction provided by Section 4.6.3 of the PMS Manual. Site suitability evaluation and regulatory compliance during site characterization are significant activities, particularly with regard to the YW MSA. OCRWM`s evaluation of whether the Yucca Mountain site is suitable for repository development must precede its submittal of a license application to the Nuclear Regulatory Commission (NRC). Accordingly, site suitability evaluation is discussed in Chapter 4, and the general statements of policy regarding site suitability evaluation are discussed in Section 2.1. Although much of the data and analyses may initially be similar, the licensing process is discussed separately in Chapter 5. Environmental compliance is discussed in Chapter 6. Safety and Health compliance is discussed in Chapter 7.

Differentiating Classroom Guidance
ERIC Educational Resources Information Center
Akos, Patrick; Cockman, Caroline R.; Strickland, Cindy A.
20070101
To differentiate is to make different, distinct, or specialized (Costello, 1994). Differentiation has become popular in education as an instructional philosophy aimed at equitably meeting the learning needs of all students in the classroom. Differentiated planning and delivery of classroom guidance is also necessary for appropriate school…

The Counseling & Guidance Curriculum.
ERIC Educational Resources Information Center
Ediger, Marlow
Counseling and guidance services are vital in any school curriculum. Counselors may themselves be dealing with students of diverse abilities and handicaps. Counselors may have to work with students affected by drug addiction, fetal alcohol syndrome, homelessness, poverty, Acquired Immune Deficiency Syndrome (AIDS) and divorce. Students may present…

Primary Guidance Activities.
ERIC Educational Resources Information Center
Hauck, Ruth, Comp.
Designed for the primary grades, the guidance activities in this document cover thirtythree topical areas: capabilities, changes, cooperation, criticism, differences, family, feelings, free time, friends, following directions, handicaps, honesty, improving environment, kindness, patience, paying attention, problem solving, rejection,…

Developmental Guidance Program Implementation.
ERIC Educational Resources Information Center
Vernon, Ann; Strub, Richard
This packet of materials was developed for workshops provided to teams of school counselors and administrators for the purpose of developing knowledge and competencies in the delivery of a comprehensive, sequential, developmental guidance program. Section I contains a rationale, definition, and description of program components. In section II…

Quality in Careers Guidance.
ERIC Educational Resources Information Center
Plant, Peter
This paper examines quality issues in career guidance, counseling, and information services in Europe and elsewhere from a range of different perspectives related to economic, ethical, and/or effectiveness criteria. Selected examples from the European Union member states, Canada, and the United States are used to illustrate how quality is…

Vocational Development and Guidance.
ERIC Educational Resources Information Center
Tennyson, W. Wesley; And Others
The vocational education volume considers questions of career development, the role of guidance in the school, vocational training, the relation of selfconcept to vocational choice, and occupational information. Twentysix papers deal with theories of vocational behavior, the success of vocational education programs, and testing information.…

A discrete fractional random transform
NASA Astrophysics Data System (ADS)
Liu, Zhengjun; Zhao, Haifa; Liu, Shutian
20051101
We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

PredGuid+A: Orion Entry Guidance Modified for Aerocapture
NASA Technical Reports Server (NTRS)
Lafleur, Jarret
20130101
PredGuid+A software was developed to enable a unique numerical predictorcorrector aerocapture guidance capability that builds on heritage Orion entry guidance algorithms. The software can be used for both planetary entry and aerocapture applications. Furthermore, PredGuid+A implements a new DeltaV minimization guidance option that can take the place of traditional targeting guidance and can result in substantial propellant savings. PredGuid+A allows the user to set a mode flag and input a target orbit's apoapsis and periapsis. Using bank angle control, the guidance will then guide the vehicle to the appropriate postaerocapture orbit using one of two algorithms: Apoapsis Targeting or DeltaV Minimization (as chosen by the user). Recently, the PredGuid guidance algorithm was adapted for use in skipentry scenarios for NASA's Orion multipurpose crew vehicle (MPCV). To leverage flight heritage, most of Orion's entry guidance routines are adapted from the Apollo program.

Discrete sequence prediction and its applications
NASA Technical Reports Server (NTRS)
Laird, Philip
19920101
Learning from experience to predict sequences of discrete symbols is a fundamental problem in machine learning with many applications. We apply sequence prediction using a simple and practical sequenceprediction algorithm, called TDAG. The TDAG algorithm is first tested by comparing its performance with some common data compression algorithms. Then it is adapted to the detailed requirements of dynamic program optimization, with excellent results.

Discrete Newtonian cosmology: perturbations
NASA Astrophysics Data System (ADS)
Ellis, George F. R.; Gibbons, Gary W.
20150301
In a previous paper (Gibbons and Ellis 2014 Discrete Newtonian cosmology Class. Quantum Grav. 31 025003), we showed how a finite system of discrete particles interacting with each other via Newtonian gravitational attraction would lead to precisely the same dynamical equations for homothetic motion as in the case of the pressurefree FriedmannLemaîtreRobertsonWalker cosmological models of general relativity theory, provided the distribution of particles obeys the central configuration equation. In this paper we show that one can obtain perturbed such Newtonian solutions that give the same linearized structure growth equations as in the general relativity case. We also obtain the DmitrievZel’dovich equations for subsystems in this discrete gravitational model, and show how it leads to the conclusion that voids have an apparent negative mass.

Discrete breathers in crystals
NASA Astrophysics Data System (ADS)
Dmitriev, S. V.; Korznikova, E. A.; Baimova, Yu A.; Velarde, M. G.
20160501
It is well known that periodic discrete defectcontaining systems, in addition to traveling waves, support vibrational defectlocalized modes. It turned out that if a periodic discrete system is nonlinear, it can support spatially localized vibrational modes as exact solutions even in the absence of defects. Since the nodes of the system are all on equal footing, it is only through the special choice of initial conditions that a group of nodes can be found on which such a mode, called a discrete breather (DB), will be excited. The DB frequency must be outside the frequency range of the smallamplitude traveling waves. Not resonating with and expending no energy on the excitation of traveling waves, a DB can theoretically conserve its vibrational energy forever provided no thermal vibrations or other perturbations are present. Crystals are nonlinear discrete systems, and the discovery in them of DBs was only a matter of time. It is well known that periodic discrete defectcontaining systems support both traveling waves and vibrational defectlocalized modes. It turns out that if a periodic discrete system is nonlinear, it can support spatially localized vibrational modes as exact solutions even in the absence of defects. Because the nodes of the system are all on equal footing, only a special choice of the initial conditions allows selecting a group of nodes on which such a mode, called a discrete breather (DB), can be excited. The DB frequency must be outside the frequency range of smallamplitude traveling waves. Not resonating with and expending no energy on the excitation of traveling waves, a DB can theoretically preserve its vibrational energy forever if no thermal vibrations or other perturbations are present. Crystals are nonlinear discrete systems, and the discovery of DBs in them was only a matter of time. Experimental studies of DBs encounter major technical difficulties, leaving atomistic computer simulations as the primary investigation tool. Despite

Deformed discrete symmetries
NASA Astrophysics Data System (ADS)
Arzano, Michele; KowalskiGlikman, Jerzy
20160901
We construct discrete symmetry transformations for deformed relativistic kinematics based on group valued momenta. We focus on the specific example of κdeformations of the Poincaré algebra with associated momenta living on (a submanifold of) de Sitter space. Our approach relies on the description of quantum states constructed from deformed kinematics and the observable charges associated with them. The results we present provide the first step towards the analysis of experimental bounds on the deformation parameter κ to be derived via precision measurements of discrete symmetries and CPT.

Modern control theory for Army missile guidance
NASA Astrophysics Data System (ADS)
Travassos, R. H.; Levari, H.; Gupta, N. K.
19821101
A Singular perturbation guidance law has been developed for mediumrange surfacetoair missiles. This guidance law is a significant extension of a previously developed guidance law for shortrange missiles; in mediumrange intercepts, the problem of energy management should be addressed in addition to homing guidance. The mathematical formulation has been simplified by introducing separation of time scales. Target Trajectory Estimation: A recursive algorithm for estimation of autoregressive moving average (ARMA) model parameters from noisy samples has been developed. Application of this algorithm to parameter estimation problems has exhibited its fast convergence and unbiasedness in the presence of noise, even with short data records. The algorithm has two versions, a Recursive Maximum Likelihood (RML) form and a Recursive Prediction Error (RPE) form, both of which possess a parallel structure that makes them highly suitable for parallelprocessing implementation. Adaptive autopilots: Latticeform algorithms have been developed for fast, recursive identification and control of timevarying systems. These algorithms have excellent numerical properties and a modular structure that makes them suitable for onboard realtime implementation.

Needed Concepts in Elementary Guidance.
ERIC Educational Resources Information Center
Warner, Tom, Ed.
School administrators and developmental guidance is the topic of the first speech. Developmental guidance, concerned with personalizing the educational experience, should be available to each child to gain selfunderstanding. Major responsibilities of the elementary guidance department are pupil appraisal, consultation, and developmental…

New Interpretations of Guidance Role
ERIC Educational Resources Information Center
Kerlan, Julius H.; Ryan, Charles W.
19720101
A panoramic view of Guidance Division general sessions and workshops covering some exemplary career guidance programs, as well as such topics as career choice, leadership, evaluation, and program development and management. Presented at the Guidance division session of the American Vocational Association 1971 annual meeting. (Editor/MU)

What Is Discrete Mathematics?
ERIC Educational Resources Information Center
Sharp, Karen Tobey
This paper cites information received from a number of sources, e.g., mathematics teachers in twoyear colleges, publishers, and convention speakers, about the nature of discrete mathematics and about what topics a course in this subject should contain. Note is taken of the book edited by Ralston and Young which discusses the future of college…

Trajectory shaping rendezvous guidance
NASA Astrophysics Data System (ADS)
Klumpp, A. R.
The Space Station will bring a great increase in rendezvous traffic. Formerly, rendezvous has been expensive in terms of time and crew involvement. Multiple trajectory adjustments on separate orbits have been required to meet safety, lighting, and geometry requirements. This paper describes a new guidance technique in which the approach trajectory is shaped by a sequence of velocity increments in order to satisfy multiple constraints within a single orbit. The approach phase is planned before the mission, leaving a group of free parameters that are optimized by onboard guidance. Fuel penalties are typically a few percent, compared to unshaped Hohmann transfers, and total fuel costs can be less than those of more timeconsuming ways of meeting the same requirements.

Environmental guidance regulatory bulletin
SciTech Connect
19970131
This document describes the background on expanding public participation in the Resource Conservation and Recovery Act and DOE`s response. The bulletin also describes the changes made by the final rule to existing regulations, guidance provided by EPA in the preamble and in the revised RCRA Public Participation Manual, the relationship between public participation and environmental justice, and DOE`s recent public participation and environmental justice initiatives.

A finite element solution for the anisotropic biphasic theory of tissueequivalent mechanics: the effect of contact guidance on isometric cell traction measurement.
PubMed
Barocas, V H; Tranquillo, R T
19970801
We present a method for solving the governing equations from our anisotropic biphasic theory of tissueequivalent mechanics (Barocas and Tranquillo, 1997) for axisymmetric problems. A mixed finite element method is used for discretization of the spatial derivatives, and the DASPK subroutine (Brown et al., 1994) is used to solve the resulting differentialalgebraic equation system. The preconditioned GMRES algorithm, using a preconditioner based on an extension of Dembo's (1994) adaptation of the Uzawa algorithm for viscous flows, provides an efficient and scaleable solution method, with the finite element method discretization being firstorder accurate in space. In the cylindrical isometric cell traction assay, the chosen test problem, a cylindrical tissue equivalent is adherent at either end to fixed circular platens. As the cells exert traction on the collagen fibrils, the force required to maintain constant sample length, or load, is measured. However, radial compaction occurs during the course of the assay, so that the cell and network concentrations increase and collagen fibrils become aligned along the axis of the cylinder, leading to cell alignment along the axis. Our simulations predict that cell contact guidance leads to an increase in the load measured in the assay, but this effect is diminished by the tendency of contact guidance to inhibit radial compaction of the sample, which in turn reduces concentrations and hence the measured load. PMID:9285339

The effect of haptic guidance and visual feedback on learning a complex tennis task.
PubMed
MarchalCrespo, Laura; van Raai, Mark; Rauter, Georg; Wolf, Peter; Riener, Robert
20131101
While haptic guidance can improve ongoing performance of a motor task, several studies have found that it ultimately impairs motor learning. However, some recent studies suggest that the haptic demonstration of optimal timing, rather than movement magnitude, enhances learning in subjects trained with haptic guidance. Timing of an action plays a crucial role in the proper accomplishment of many motor skills, such as hitting a moving object (discrete timing task) or learning a velocity profile (timecritical tracking task). The aim of the present study is to evaluate which feedback conditionsvisual or haptic guidanceoptimize learning of the discrete and continuous elements of a timing task. The experiment consisted in performing a fast tennis forehand stroke in a virtual environment. A tendonbased parallel robot connected to the end of a racket was used to apply haptic guidance during training. In two different experiments, we evaluated which feedback condition was more adequate for learning: (1) a timedependent discrete tasklearning to start a tennis stroke and (2) a tracking tasklearning to follow a velocity profile. The effect that the task difficulty and subject's initial skill level have on the selection of the optimal training condition was further evaluated. Results showed that the training condition that maximizes learning of the discrete timedependent motor task depends on the subjects' initial skill level. Haptic guidance was especially suitable for lessskilled subjects and in especially difficult discrete tasks, while visual feedback seems to benefit more skilled subjects. Additionally, haptic guidance seemed to promote learning in a timecritical tracking task, while visual feedback tended to deteriorate the performance independently of the task difficulty and subjects' initial skill level. Haptic guidance outperformed visual feedback, although additional studies are needed to further analyze the effect of other types of feedback visualization on

Discreteness induced extinction
NASA Astrophysics Data System (ADS)
dos Santos, Renato Vieira; da Silva, Linaena Méricy
20151101
Two simple models based on ecological problems are discussed from the point of view of nonequilibrium statistical mechanics. It is shown how discrepant may be the results of the models that include spatial distribution with discrete interactions when compared with the continuous analogous models. In the continuous case we have, under certain circumstances, the population explosion. When we take into account the finiteness of the population, we get the opposite result, extinction. We will analyze how these results depend on the dimension d of the space and describe the phenomenon of the "Discreteness Inducing Extinction" (DIE). The results are interpreted in the context of the "paradox of sex", an old problem of evolutionary biology.

Missionbased guidance system design for autonomous UAVs
NASA Astrophysics Data System (ADS)
Moon, Jongki
The advantages of UAVs in the aviation arena have led to extensive research activities on autonomous technology of UAVs to achieve specific mission objectives. This thesis mainly focuses on the development of a missionbased guidance system. Among various missions expected for future needs, autonomous formation flight (AFF) and obstacle avoidance within safe operation limits are investigated. In the design of an adaptive guidance system for AFF, the leader information except position is assumed to be unknown to a follower. Thus, the only measured information related to the leader is the lineofsight (LOS) range and angle. Adding an adaptive element with neural networks into the guidance system provides a capability to effectively handle leader's velocity changes. Therefore, this method can be applied to the AFF control systems that use a passive sensing method. In this thesis, an adaptive velocity command guidance system and an adaptive acceleration command guidance system are developed and presented. Since relative degrees of the LOS range and angle are different depending on the outputs from the guidance system, the architecture of the guidance system changes accordingly. Simulations and flight tests are performed using the Georgia Tech UAV helicopter, the GTMax, to evaluate the proposed guidance systems. The simulation results show that the neural network (NN) based adaptive element can improve the tracking performance by effectively compensating for the effect of unknown dynamics. It has also been shown that the combination of an adaptive velocity command guidance system and the existing GTMax autopilot controller performs better than the combination of an adaptive acceleration command guidance system and the GTMax autopilot controller. The successful flight evaluation using an adaptive velocity command guidance system clearly shows that the adaptive guidance control system is a promising solution for autonomous formation flight of UAVs. In addition, an

A paradigm for discrete physics
SciTech Connect
Noyes, H.P.; McGoveran, D.; Etter, T.; Manthey, M.J.; Gefwert, C.
19870101
An example is outlined for constructing a discrete physics using as a starting point the insight from quantum physics that events are discrete, indivisible and nonlocal. Initial postulates are finiteness, discreteness, finite computability, absolute nonuniqueness (i.e., homogeneity in the absence of specific cause) and additivity.

A simplified guidance algorithm for lifting aeroassist orbital transfer vehicles
NASA Technical Reports Server (NTRS)
Cerimele, C. J.; Gamble, J. D.
19850101
The derivation, logic, and performance of a simplified atmospheric guidance algorithm for aeroassist orbitaltransfer vehicles (AOTVs) are presented. The algorithm was developed to meet the demands for an aerobraking trajectory guidance technique that was uncomplicated, easily integrated into existing trajectory programs, adaptable to a range of vehicle aerodynamic configurations, capable of performance equivalent to currently available guidance programs in compensating for dispersions in entry conditions, atmospheric conditions, and aerodynamic characteristics. The result was a hybrid lifting guidance algorithm combining the method of referenceprofile generation with the method of predictor/corrector schemes. The resulting performance is good (less than 3 n.m. error from desired apogee despite uncertainties of + or  50 percent atmospheric density, + or  0.2 deg entry flightpath angle, or + or  50 percent L/D. Combinations of these same dispersions with lesser magnitudes have also been successful, although performance with density 'pockets' within the atmosphere requires more analysis.

Guidance and Control Architecture Design and Demonstration for Low Ballistic Coefficient Atmospheric Entry
NASA Technical Reports Server (NTRS)
Swei, Sean
20140101
We propose to develop a robust guidance and control system for the ADEPT (Adaptable Deployable Entry and Placement Technology) entry vehicle. A controlcentric model of ADEPT will be developed to quantify the performance of candidate guidance and control architectures for both aerocapture and precision landing missions. The evaluation will be based on recent breakthroughs in constrained controllability/reachability analysis of control systems and constrainedbased energyminimum trajectory optimization for guidance development operating in complex environments.

Stationkeeping guidance
NASA Technical Reports Server (NTRS)
Gustafson, D. E.; Kriegsman, B. A.
19720101
The stationkeeping guidance system is described, which is designed to automatically keep one orbiting vehicle within a prescribed zone fixed with respect to another orbiting vehicle. The active vehicle, i.e. the one performing the stationkeeping maneuvers, is referred to as the shuttle. The other passive orbiting vehicle is denoted as the workshop. The passive vehicle is assumed to be in a loweccentricity nearearth orbit. The primary navigation sensor considered is a gimballed tracking radar located on board the shuttle. It provides data on relative range and range rate between the two vehicles. Also measured are the shaft and trunnion axes gimbal angles. An inertial measurement unit (IMU) is provided on board the orbiter. The IMU is used at all times to provide an attitude reference for the vehicle. The IMU accelerometers are used periodically to monitor the velocitycorrection burns applied to the shuttle during the stationkeeping mode. The guidance system is capable of stationkeeping the shuttle in any arbitrary position with respect to the workshop by periodically applying velocitycorrection pulses to the shuttle.

Guidance of Nonlinear Systems
NASA Technical Reports Server (NTRS)
Meyer, George
19970101
The paper describes a method for guiding a dynamic system through a given set of points. The paradigm is a fully automatic aircraft subject to air traffic control (ATC). The ATC provides a sequence of way points through which the aircraft trajectory must pass. The way points typically specify time, position, and velocity. The guidance problem is to synthesize a system state trajectory which satisfies both the ATC and aircraft constraints. Complications arise because the controlled process is multidimensional, multiaxis, nonlinear, highly coupled, and the state space is not flat. In addition, there is a multitude of possible operating modes, which may number in the hundreds. Each such mode defines a distinct state space model of the process by specifying the state space coordinatization, the partition of the controls into active controls and configuration controls, and the output map. Furthermore, mode transitions must be smooth. The guidance algorithm is based on the inversion of the pure feedback approximations, which is followed by iterative corrections for the effects of zero dynamics. The paper describes the structure and modules of the algorithm, and the performance is illustrated by several example aircraft maneuvers.

Bilinear tangent yaw guidance
NASA Technical Reports Server (NTRS)
Brusch, R. G.
19790101
This paper presents a parametric yaw steering law which has been used to provide closedloop yaw guidance for the launch of the HEAO (High Energy Astronomy Observatory) satellite mission using the Atlas/Centaur launch vehicle. This bilinear tangent steering law provides near optimal yaw steering for maneuvers requiring insertion into orbits with a specified inclination and node. Bilinear tangent steering is shown to be optimal in both the pitch and yaw planes when a uniform gravitational field is assumed. The conditions under which the general bilinear tangent laws degenerate into linear tangent and constant attitude laws are presented. The flight computer implementation of these laws in a rotating coordinate system using realtime integration of the equations of motion is detailed. Explicit solution of the parametric guidance equations requires the inflight solution of (2x2) twopoint boundary value problems in the pitch and yaw planes. Excellent results are obtained even for very large (greater than 50 deg) outofplane steering angles.

Partial stabilizationbased guidance.
PubMed
Shafiei, M H; Binazadeh, T
20120101
A novel nonlinear missile guidance law against maneuvering targets is designed based on the principles of partial stability. It is demonstrated that in a real approach which is adopted with actual situations, each state of the guidance system must have a special behavior and asymptotic stability or exponential stability of all states is not realistic. Thus, a new guidance law is developed based on the partial stability theorem in such a way that the behaviors of states in the closedloop system are in conformity with a real guidance scenario that leads to collision. The performance of the proposed guidance law in terms of interception time and control effort is compared with the sliding mode guidance law by means of numerical simulations. PMID:21963401

SemiDiscrete InghamType Inequalities
SciTech Connect
Komornik, Vilmos Loreti, Paola
20070315
One of the general methods in linear control theory is based on harmonic and nonharmonic Fourier series. The key of this approach is the establishment of various suitable adaptations and generalizations of the classical Parseval equality. A new and systematic approach was begun in our papers in collaboration with Baiocchi. Many recent results of this kind, obtained through various Inghamtype theorems, were exposed recently. Although this work concentrated on continuous models, in connection with numerical simulations a natural question is whether these results also admit useful discrete versions. The purpose of this paper is to establish discrete versions of various Inghamtype theorems by using our approach. They imply the earlier continuous results by a simple limit process.

Multiple Autonomous Discrete Event Controllers for Constellations
NASA Technical Reports Server (NTRS)
Esposito, Timothy C.
20030101
The Multiple Autonomous Discrete Event Controllers for Constellations (MADECC) project is an effort within the National Aeronautics and Space Administration Goddard Space Flight Center's (NASA/GSFC) Information Systems Division to develop autonomous positioning and attitude control for constellation satellites. It will be accomplished using traditional control theory and advanced coordination algorithms developed by the Johns Hopkins University Applied Physics Laboratory (JHU/APL). This capability will be demonstrated in the discrete event control testbed located at JHU/APL. This project will be modeled for the Leonardo constellation mission, but is intended to be adaptable to any constellation mission. To develop a common software architecture. the controllers will only model very highlevel responses. For instance, after determining that a maneuver must be made. the MADECC system will output B (Delta)V (velocity change) value. Lower level systems must then decide which thrusters to fire and for how long to achieve that (Delta)V.

MULTISCALE DISCRETIZATION OF SHAPE CONTOURS
SciTech Connect
Prasad, L.; Rao, R.
20000901
We present an efficient multiscale scheme to adaptively approximate the continuous (or densely sampled) contour of a planar shape at varying resolutions. The notion of shape is intimately related to the notion of contour, and the efficient representation of the contour of a shape is vital to a computational understanding of the shape. Any polygonal approximation of a planar smooth curve is equivalent to a piecewise constant approximation of the parameterized X and Y coordinate functions of a discrete point set obtained by densely sampling the curve. Using the Haar wavelet transform for the piecewise approximation yields a hierarchical scheme in which the size of the approximating point set is traded off against the morphological accuracy of the approximation. Our algorithm compresses the representation of the initial shape contour to a sparse sequence of points in the plane defining the vertices of the shape's polygonal approximation. Furthermore, it is possible to control the overall resolution of the approximation by a single, scaleindependent parameter.

Discrete chaotic cryptography
NASA Astrophysics Data System (ADS)
Kotulski, Zbigniew; Szczepaski, Janusz
In the paper we propose a new method of constructing cryptosystems utilising a nonpredictability property of discrete chaotic systems. We formulate the requirements for such systems to assure their safety. We also give examples of practical realisation of chaotic cryptosystems, using a generalisation of the method presented in [7]. The proposed algorithm of encryption and decryption is based on multiple iteration of a certain dynamical chaotic system. We assume that some part of the initial condition is a plain message. As the secret key we assume the system parameter(s) and additionally another part of the initial condition.

Discrete Dynamics Lab
NASA Astrophysics Data System (ADS)
Wuensche, Andrew
DDLab is interactive graphics software for creating, visualizing, and analyzing many aspects of Cellular Automata, Random Boolean Networks, and Discrete Dynamical Networks in general and studying their behavior, both from the timeseries perspective — spacetime patterns, and from the statespace perspective — attractor basins. DDLab is relevant to research, applications, and education in the fields of complexity, selforganization, emergent phenomena, chaos, collisionbased computing, neural networks, content addressable memory, genetic regulatory networks, dynamical encryption, generative art and music, and the study of the abstract mathematical/physical/dynamical phenomena in their own right.

Beyond Discipline to Guidance: A Primer on the Guidance Alternative.
ERIC Educational Resources Information Center
Gartrell, Dan
As early childhood teachers apply principles of guidance rather than punishment in their classrooms, they face the challenge of avoiding a slippage into traditional discipline practices and transcending the punitive aspects of discipline. Guidance is designed to teach children democratic life skills and therefore goes beyond discipline. Teachers…

Discrete range clustering using Monte Carlo methods
NASA Technical Reports Server (NTRS)
Chatterji, G. B.; Sridhar, B.
19930101
For automatic obstacle avoidance guidance during rotorcraft low altitude flight, a reliable model of the nearby environment is needed. Such a model may be constructed by applying surface fitting techniques to the dense range map obtained by active sensing using radars. However, for covertness, passive sensing techniques using electrooptic sensors are desirable. As opposed to the dense range map obtained via active sensing, passive sensing algorithms produce reliable range at sparse locations, and therefore, surface fitting techniques to fill the gaps in the range measurement are not directly applicable. Both for automatic guidance and as a display for aiding the pilot, these discrete ranges need to be grouped into sets which correspond to objects in the nearby environment. The focus of this paper is on using Monte Carlo methods for clustering range points into meaningful groups. One of the aims of the paper is to explore whether simulated annealing methods offer significant advantage over the basic Monte Carlo method for this class of problems. We compare three different approaches and present application results of these algorithms to a laboratory image sequence and a helicopter flight sequence.

Endangerment assessment guidance
SciTech Connect
Not Available
19851122
The directive clarifies the requirement that an endangerment assessment be developed to support all administrative and judicial enforcement actions under Section 106 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Section 7003 of the Resource Conservation and Recovery Act (RCRA). Before taking enforcement action under these provisions to abate the hazards or potential hazards at a site, the Environmental Protection Agency (EPA) must be able to properly document and justify its assertion that an imminent and substantial endangerment to public health or welfare or the environment may exist. The endangerment assessment provides this documentation and justification. The endangerment assessment is not necessary to support Section 104 actions. It also provides guidance on the content, timing, level of detail, format, and resources required for the preparation of endangerment assessments.

DiscreteTime Goldfishing
NASA Astrophysics Data System (ADS)
Calogero, Francesco
20110801
The original continuoustime ''goldfish'' dynamical system is characterized by two neat formulas, the first of which provides the N Newtonian equations of motion of this dynamical system, while the second provides the solution of the corresponding initialvalue problem. Several other, more general, solvable dynamical systems ''of goldfish type'' have been identified over time, featuring, in the righthand (''forces'') side of their Newtonian equations of motion, in addition to other contributions, a velocitydependent term such as that appearing in the righthand side of the first formula mentioned above. The solvable character of these models allows detailed analyses of their behavior, which in some cases is quite remarkable (for instance isochronous or asymptotically isochronous). In this paper we introduce and discuss various discretetime dynamical systems, which are as well solvable, which also display interesting behaviors (including isochrony and asymptotic isochrony) and which reduce to dynamical systems of goldfish type in the limit when the discretetime independent variable l=0,1,2,... becomes the standard continuoustime independent variable t, 0≤t<∞.

Interventional tool tracking using discrete optimization.
PubMed
Heibel, Hauke; Glocker, Ben; Groher, Martin; Pfister, Marcus; Navab, Nassir
20130301
This work presents a novel scheme for tracking of motion and deformation of interventional tools such as guidewires and catheters in fluoroscopic Xray sequences. Being able to track and thus to estimate the correct positions of these tools is crucial in order to offer guidance enhancement during interventions. The task of estimating the apparent motion is particularly challenging due to the low signaltonoise ratio (SNR) of fluoroscopic images and due to combined motion components originating from patient breathing and tool interactions performed by the physician. The presented approach is based on modeling interventional tools with Bsplines whose optimal configuration of control points is determined through efficient discrete optimization. Each control point corresponds to a discrete random variable in a Markov random field (MRF) formulation where a set of labels represents the deformation space. In this context, the optimal curve corresponds to the maximum a posteriori (MAP) estimate of the MRF energy. The main motivation for employing a discrete approach is the possibility to incorporate a multidirectional search space which is robust to local minima. This is of particular interest for curve tracking under large deformation. This work analyzes feasibility of employing efficient firstorder MRFs for tracking. In particular it shows how to achieve a good compromise between energy approximations and computational efficiency. Experimental results suggest to define both the external and internal energy in terms of pairwise potential functions. The method was successfully applied to the tracking of guidewires in fluoroscopic Xray sequences of several hundred frames which requires extremely robust techniques. Comparisons with stateoftheart guidewire tracking algorithms confirm the effectiveness of the proposed method. PMID:23232412

Guidance for the New Millenium?
ERIC Educational Resources Information Center
McLaren, David J.
19960101
Reviews the "Guidance Arrangements" consultation document issued with "Higher Still" (proposed new Scottish upper secondary curricula). Argues that the paper ignores the full implications for educational change in Higher Still and misses the opportunity for timely modernization of school guidance. Advocates a crosscurricular model of guidance…

Push drill guidance indication apparatus
SciTech Connect
Bockhorst, R.W.; Elenburg, J.H.
19840605
The present invention relates to a program controlled apparatus for providing rapid calibration and update of sensor parameters in a push drill guidance apparatus which is remotely controllable from microprocessor circuitry. A special calibration program is set into nonvolatile memory for coaction with the control processor to compute sensor parameters for storage and recall during normal programmed guidance operation.

Guidance in the Secondary School
ERIC Educational Resources Information Center
Kumar, V. Jurist Lional
20100101
Secondary School Students face a lot of problems in their body as well as in mind due to puberty that tends to adolescence stage. Adolescence has peculiar characters of their own. They need proper Guidance and Counselling to tackle their own problems. Guidance is described as a counselling service to assist the individual in achieving self…

Discussing Diverse Perspectives on Guidance
ERIC Educational Resources Information Center
GonzalezMena, Janet; Shareef, Intisar
20050101
Ideas about discipline and guidance get extremely complex when they intersect with culture and oppression. Some groups of people who are targets of racism have to protect their children from the oppressive practices of racist individuals and institutions. Their methods of guidance and discipline may be different from those of groups for whom…

Automated Guidance for Student Inquiry
ERIC Educational Resources Information Center
Gerard, Libby F.; Ryoo, Kihyun; McElhaney, Kevin W.; Liu, Ou Lydia; Rafferty, Anna N.; Linn, Marcia C.
20160101
In 4 classroom experiments we investigated uses for technologies that automatically score student generated essays, concept diagrams, and drawings in inquiry curricula. We used the automatic scores to assign typical and researchbased guidance and studied the impact of the guidance on student progress. Seven teachers and their 897 students…

Guidance: Agent of the Counterculture.
ERIC Educational Resources Information Center
Patouillet, Raymond A.; Marin, Roselyn L.
19790101
This article was an introduction to a convention program presented at the Florida Personnel and Guidance Association Convention (Tampa, Nov., 1977) by Raymond Patouillet, shortly before his sudden death. It encapsulates his guidance philosophy, his understanding of the human condition, and his faith in the crucial role of the caring profession.…

Innovative Approaches to Career Guidance.
ERIC Educational Resources Information Center
Freeman, Andrew R.
A key part of a broadbased approach to career education in Australian schools is vocational/career guidance. Various vocational guidance programs have been developed for specific groups in Australian society, including work experience, caravans, and micrographics technology for the handicapped; preemployment courses and a family education center…

Marxist Guidance: A Dialectic Lesson
ERIC Educational Resources Information Center
Drapela, Victor J.
19710101
Based on primary sources published in the Soviet Bloc, this article compares the stated goals of Marxist guidance with actual outcomes, and identifies the foundations of guidance in the Soviet Bloc in terms of Marxist philosophy and social doctrine. Current symptoms of ideological unrest in socialist society as exemplified by the suppressed reform…

Discrete Mechanics and Optimal Control for Space Trajectory Design
NASA Astrophysics Data System (ADS)
Moore, Ashley
Space trajectory design is often achieved through a combination of dynamical systems theory and optimal control. The union of trajectory design techniques utilizing invariant manifolds of the planar circular restricted threebody problem and the optimal control scheme Discrete Mechanics and Optimal Control (DMOC) facilitates the design of lowenergy trajectories in the Nbody problem. In particular, DMOC is used to optimize a trajectory from the Earth to the Moon in the 4body problem, removing the midcourse change in velocity, Delta V, usually necessary for such a trajectory while still exploiting the structure from the invariant manifolds. This thesis also focuses on how to adapt DMOC, a method devised with a constant step size, for the highly nonlinear dynamics involved in trajectory design. Mesh refinement techniques that aim to reduce discretization errors in the solution and energy evolution and their effect on DMOC optimization are explored and compared with trajectories created using time adaptive variational integrators. Furthermore, a time adaptive form of DMOC is developed that allows for a variable step size that is updated throughout the optimization process. Time adapted DMOC is based on a discretization of Hamilton's principle applied to the time adapted Lagrangian of the optimal control problem. Variations of the discrete action of the optimal control Lagrangian lead to discrete EulerLagrange equations that can be enforced as constraints for a boundary value problem. This new form of DMOC leads to the accurate and efficient solution of optimal control problems with highly nonlinear dynamics. Time adapted DMOC is tested on several space trajectory problems including the elliptical orbit transfer in the 2body problem and the reconfiguration of a cubesat.

Signaling from axon guidance receptors.
PubMed
Bashaw, Greg J; Klein, Rüdiger
20100501
Determining how axon guidance receptors transmit signals to allow precise pathfinding decisions is fundamental to our understanding of nervous system development and may suggest new strategies to promote axon regeneration after injury or disease. Signaling mechanisms that act downstream of four prominent families of axon guidance cuesnetrins, semaphorins, ephrins, and slitshave been extensively studied in both invertebrate and vertebrate model systems. Although details of these signaling mechanisms are still fragmentary and there appears to be considerable diversity in how different guidance receptors regulate the motility of the axonal growth cone, a number of common themes have emerged. Here, we review recent insights into how specific receptors for each of these guidance cues engage downstream regulators of the growth cone cytoskeleton to control axon guidance. PMID:20452961

Ascent Guidance for a Winged Boost Vehicle. M.S. Thesis
NASA Technical Reports Server (NTRS)
Corvin, Michael Alexander
19880101
The objective of the advanced ascent guidance study was to investigate guidance concepts which could contribute to increased autonomy during ascent operations in a winged boost vehicle such as the proposed Shuttle II. The guidance scheme was required to yield near a fulloptimal ascent in the presence of vehicle system and environmental dispersions. The study included consideration of trajectory shaping issues, trajectory design, closed loop and predictive adaptive guidance techniques and control of dynamic pressure by throttling. An extensive ascent vehicle simulation capability was developed for use in the study.

Discrete antigravity
SciTech Connect
Noyes, H.P. ); Starson, S. )
19910301
Discrete physics, because it replaces time evolution generated by the energy operator with a global bitstring generator (program universe) and replaces fields'' with the relativistic WheelerFeynman action at a distance,'' allows the consistent formulation of the concept of signed gravitational charge for massive particles. The resulting prediction made by this version of the theory is that free antiparticles near the surface of the earth will fall'' up with the same acceleration that the corresponding particles fall down. So far as we can see, no current experimental information is in conflict with this prediction of our theory. The experiment crusis will be one of the antiproton or antihydrogen experiments at CERN. Our prediction should be much easier to test than the small effects which those experiments are currently designed to detect or bound. 23 refs.

Discrete Sibson interpolation.
PubMed
Park, Sung W; Linsen, Lars; Kreylos, Oliver; Owens, John D; Hamann, Bernd
20060101
Naturalneighbor interpolation methods, such as Sibson's method, are wellknown schemes for multivariate data fitting and reconstruction. Despite its many desirable properties, Sibson's method is computationally expensive and difficult to implement, especially when applied to higherdimensional data. The main reason for both problems is the method's implementation based on a Voronoi diagram of all data points. We describe a discrete approach to evaluating Sibson's interpolant on a regular grid, based solely on finding nearest neighbors and rendering and blending ddimensional spheres. Our approach does not require us to construct an explicit Voronoi diagram, is easily implemented using commodity threedimensional graphics hardware, leads to a significant speed increase compared to traditional approaches, and generalizes easily to higher dimensions. For large scattered data sets, we achieve twodimensional (2D) interpolation at interactive rates and 3D interpolation (3D) with computation times of a few seconds. PMID:16509383

Discrete Pearson distributions
SciTech Connect
Bowman, K.O.; Shenton, L.R.; Kastenbaum, M.A.
19911101
These distributions are generated by a first order recursive scheme which equates the ratio of successive probabilities to the ratio of two corresponding quadratics. The use of a linearized form of this model will produce equations in the unknowns matched by an appropriate set of moments (assumed to exist). Given the moments we may find valid solutions. These are two cases; (1) distributions defined on the nonnegative integers (finite or infinite) and (2) distributions defined on negative integers as well. For (1), given the first four moments, it is possible to set this up as equations of finite or infinite degree in the probability of a zero occurrence, the sth component being a product of s ratios of linear forms in this probability in general. For (2) the equation for the zero probability is purely linear but may involve slowly converging series; here a particular case is the discrete normal. Regions of validity are being studied. 11 refs.

Immigration and Prosecutorial Discretion
PubMed Central
Apollonio, Dorie; Lochner, Todd; Heddens, Myriah
20150101
Immigration has become an increasingly salient national issue in the US, and the Department of Justice recently increased federal efforts to prosecute immigration offenses. This shift, however, relies on the cooperation of US attorneys and their assistants. Traditionally federal prosecutors have enjoyed enormous discretion and have been responsive to local concerns. To consider how the centralized goal of immigration enforcement may have influenced federal prosecutors in regional offices, we review their prosecution of immigration offenses in California using over a decade's worth of data. Our findings suggest that although centralizing forces influence immigration prosecutions, individual US attorneys' offices retain distinct characteristics. Local factors influence federal prosecutors' behavior in different ways depending on the office. Contrary to expectations, unemployment rates did not affect prosecutors' willingness to pursue immigration offenses, nor did local popular opinion about illegal immigration. PMID:26146530

Discrete stability in stochastic programming
SciTech Connect
Lepp, R.
19941231
In this lecture we study stability properties of stochastic programs with recourse where the probability measure is approximated by a sequence of weakly convergent discrete measures. Such discrete approximation approach gives us a possibility to analyze explicitly the behavior of the second stage correction function. The approach is based on modern functional analytical methods of an approximation of extremum problems in function spaces, especially on the notion of the discrete convergence of vectors to an essentially bounded measurable function.

RH Packaging Program Guidance
SciTech Connect
Washington TRU Solutions LLC
20080112
The purpose of this program guidance document is to provide the technical requirements for use, operation, inspection, and maintenance of the RHTRU 72B Waste Shipping Package (also known as the "RHTRU 72B cask") and directly related components. This document complies with the requirements as specified in the RHTRU 72B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the C of C shall govern. The C of C states: "...each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, Operating Procedures, of the application." It further states: "...each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, Acceptance Tests and Maintenance Program of the Application." Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M&O) Contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRCapproved, users need to be familiar with Title 10 Code of Federal Regulations (CFR) §71.8, "Deliberate Misconduct." Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) shall be notified immediately. The CBFO will evaluate the issue and notify the NRC if required.In accordance with 10 CFR Part 71, "Packaging and Transportation of Radioactive Material," certificate holders, packaging users, and contractors or subcontractors who use, design, fabricate, test, maintain, or modify the packaging shall post copies of (1) 10 CFR Part 21, "Reporting of Defects and Noncompliance," regulations, (2) Section 206 of the Energy Reorganization Act of 1974, and (3) NRC Form 3, Notice to Employees. These documents must be posted in a

RH Packaging Program Guidance
SciTech Connect
Washington TRU Solutions LLC
20061107
The purpose of this program guidance document is to provide the technical requirements for use, operation, inspection, and maintenance of the RHTRU 72B Waste Shipping Package and directly related components. This document complies with the requirements as specified in the RHTRU 72B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the C of C shall govern. The C of C states: "...each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, Operating Procedures, of the application." It further states: "...each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, Acceptance Tests and Maintenance Program of the Application." Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M&O) Contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRCapproved, users need to be familiar with 10 Code of Federal Regulations (CFR) §71.8, "Deliberate Misconduct." Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) shall be notified immediately. CBFO will evaluate the issue and notify the NRC if required. In accordance with 10 CFR Part 71, "Packaging and Transportation of Radioactive Material," certificate holders, packaging users, and contractors or subcontractors who use, design, fabricate, test, maintain, or modify the packaging shall post copies of (1) 10 CFR Part 21, "Reporting of Defects and Noncompliance," regulations, (2) Section 206 of the Energy Reorganization Act of 1974, and (3) NRC Form 3, Notice to Employees. These documents must be posted in a conspicuous location where the activities subject to

Fast and Accurate Learning When Making Discrete Numerical Estimates.
PubMed
Sanborn, Adam N; Beierholm, Ulrik R
20160401
Many everyday estimation tasks have an inherently discrete nature, whether the task is counting objects (e.g., a number of paint buckets) or estimating discretized continuous variables (e.g., the number of paint buckets needed to paint a room). While Bayesian inference is often used for modeling estimates made along continuous scales, discrete numerical estimates have not received as much attention, despite their common everyday occurrence. Using two tasks, a numerosity task and an area estimation task, we invoke Bayesian decision theory to characterize how people learn discrete numerical distributions and make numerical estimates. Across three experiments with novel stimulus distributions we found that participants fell between two common decision functions for converting their uncertain representation into a response: drawing a sample from their posterior distribution and taking the maximum of their posterior distribution. While this was consistent with the decision function found in previous work using continuous estimation tasks, surprisingly the prior distributions learned by participants in our experiments were much more adaptive: When making continuous estimates, participants have required thousands of trials to learn bimodal priors, but in our tasks participants learned discrete bimodal and even discrete quadrimodal priors within a few hundred trials. This makes discrete numerical estimation tasks good testbeds for investigating how people learn and make estimates. PMID:27070155

Fast and Accurate Learning When Making Discrete Numerical Estimates
PubMed Central
Sanborn, Adam N.; Beierholm, Ulrik R.
20160101
Many everyday estimation tasks have an inherently discrete nature, whether the task is counting objects (e.g., a number of paint buckets) or estimating discretized continuous variables (e.g., the number of paint buckets needed to paint a room). While Bayesian inference is often used for modeling estimates made along continuous scales, discrete numerical estimates have not received as much attention, despite their common everyday occurrence. Using two tasks, a numerosity task and an area estimation task, we invoke Bayesian decision theory to characterize how people learn discrete numerical distributions and make numerical estimates. Across three experiments with novel stimulus distributions we found that participants fell between two common decision functions for converting their uncertain representation into a response: drawing a sample from their posterior distribution and taking the maximum of their posterior distribution. While this was consistent with the decision function found in previous work using continuous estimation tasks, surprisingly the prior distributions learned by participants in our experiments were much more adaptive: When making continuous estimates, participants have required thousands of trials to learn bimodal priors, but in our tasks participants learned discrete bimodal and even discrete quadrimodal priors within a few hundred trials. This makes discrete numerical estimation tasks good testbeds for investigating how people learn and make estimates. PMID:27070155

Exploring Discretization Error in SimulationBased Aerodynamic Databases
NASA Technical Reports Server (NTRS)
Aftosmis, Michael J.; Nemec, Marian
20100101
This work examines the level of discretization error in simulationbased aerodynamic databases and introduces strategies for error control. Simulations are performed using a parallel, multilevel Euler solver on embeddedboundary Cartesian meshes. Discretization errors in userselected outputs are estimated using the method of adjointweighted residuals and we use adaptive mesh refinement to reduce these errors to specified tolerances. Using this framework, we examine the behavior of discretization error throughout a token database computed for a NACA 0012 airfoil consisting of 120 cases. We compare the cost and accuracy of two approaches for aerodynamic database generation. In the first approach, mesh adaptation is used to compute all cases in the database to a prescribed level of accuracy. The second approach conducts all simulations using the same computational mesh without adaptation. We quantitatively assess the error landscape and computational costs in both databases. This investigation highlights sensitivities of the database under a variety of conditions. The presence of transonic shocks or the stiffness in the governing equations near the incompressible limit are shown to dramatically increase discretization error requiring additional mesh resolution to control. Results show that such pathologies lead to error levels that vary by over factor of 40 when using a fixed mesh throughout the database. Alternatively, controlling this sensitivity through mesh adaptation leads to mesh sizes which span two orders of magnitude. We propose strategies to minimize simulation cost in sensitive regions and discuss the role of errorestimation in database quality.

Development of a Tactical Guidance Research and Evaluation System (TGRES)
NASA Technical Reports Server (NTRS)
Goodrich, Kenneth H.; McManus, John W.
19890101
The development of a simulation tool for tactical guidance research and the evaluation of systems performance in a tactically significant environment is described. The objective of the tool is to provide a means by which researchers can explore and exploit enhancements to airplane agility. The completed tool will include highfidelity batch and piloted simulation capabilities, an advanced tactical guidance logic and a userfriendly interface. While the tool is being developed for the purpose of studying airplane agility, its modularity should make it easily adaptable to the analysis of other technologies and thus be of interest to a number of potential users.

Autonomous landing guidance program
NASA Astrophysics Data System (ADS)
Brown, John A.
19960501
The Autonomous Landing Guidance program is partly funded by the US Government under the Technology Reinvestment Project. The program consortium consists of avionics and other equipment vendors, airlines and the USAF. A Sextant Avionique HUD is used to present flight symbology in cursive form as well as millimeter wave radar imagery from Lear Astronics equipment and FLIR Systems dualchannel, forwardlooking, infrared imagery. All sensor imagery is presented in raster form. A future aim is to fuse all imagery data into a single presentation. Sensor testing has been accomplished in a Cessna 402 operated by the Maryland Advanced Development Laboratory. Development testing is under way in a Northwest Airlines simulator equipped with HUD and image simulation. Testing is also being carried out using United Airlines Boeing 727 and USAF C135C (Boeing 707) test aircraft. The paper addresses the technology utilized in sensory and display systems as well as modifications made to accommodate the elements in the aircraft. Additions to the system test aircraft include global positioning systems, inertial navigation systems and extensive data collection equipment. Operational philosophy and benefits for both civil and military users are apparent. Approach procedures have been developed allowing use of Category 1 ground installations in Category 3 conditions.

Uprated fine guidance sensor study
NASA Technical Reports Server (NTRS)
19840101
Future orbital observatories will require star trackers of extremely high precision. These sensors must maintain high pointing accuracy and pointing stability simultaneously with a low light level signal from a guide star. To establish the fine guidance sensing requirements and to evaluate candidate fine guidance sensing concepts, the Space Telescope Optical Telescope Assembly was used as the reference optical system. The requirements review was separated into three areas: Optical Telescope Assembly (OTA), Fine Guidance Sensing and astrometry. The results show that the detectors should be installed directly onto the focal surface presented by the optics. This would maximize throughput and minimize point stability error by not incoporating any additional optical elements.

Adaptive optics ophthalmoscopy
PubMed Central
Roorda, Austin; Duncan, Jacque L.
20160101
This review starts with a brief history and description of adaptive optics (AO) technology, followed by a showcase of the latest capabilities of AO systems for imaging the human retina and an extensive review of the literature on where AO is being used clinically. The review concludes with a discussion on future directions and guidance on usage and interpretation of images from AO systems for the eye. PMID:26973867

RH Packaging Program Guidance
SciTech Connect
Washington TRU Solutions, LLC
20030825
The purpose of this program guidance document is to provide technical requirements for use, operation, inspection, and maintenance of the RHTRU 72B Waste Shipping Package and directly related components. This document complies with the requirements as specified in the RHTRU 72B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the SARP and/or C of C shall govern. The C of C states: ''...each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, ''Operating Procedures,'' of the application.'' It further states: ''...each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, ''Acceptance Tests and Maintenance Program of the Application.'' Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M&O) contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRC approved, users need to be familiar with 10 CFR {section} 71.11, ''Deliberate Misconduct.'' Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the Carlsbad Field Office (CBFO) shall be notified immediately. CBFO will evaluate the issue and notify the NRC if required. This document details the instructions to be followed to operate, maintain, and test the RHTRU 72B packaging. This Program Guidance standardizes instructions for all users. Users shall follow these instructions. Following these instructions assures that operations are safe and meet the requirements of the SARP. This document is available on the Internet at: ttp://www.ws/library/t2omi/t2omi.htm. Users are responsible for ensuring they are using the current revision and change notices. Sites may prepare their own document using the word

Discrete Mathematics and Curriculum Reform.
ERIC Educational Resources Information Center
Kenney, Margaret J.
19960101
Defines discrete mathematics as the mathematics necessary to effect reasoned decision making in finite situations and explains how its use supports the current view of mathematics education. Discrete mathematics can be used by curriculum developers to improve the curriculum for students of all ages and abilities. (SLD)

Discrete Mathematics and Its Applications
ERIC Educational Resources Information Center
Oxley, Alan
20100101
The article gives ideas that lecturers of undergraduate Discrete Mathematics courses can use in order to make the subject more interesting for students and encourage them to undertake further studies in the subject. It is possible to teach Discrete Mathematics with little or no reference to computing. However, students are more likely to be…

Video guidance sensor
NASA Technical Reports Server (NTRS)
Howard, Richard
19910101
A MartinMarietta study comparing the application of laser, video, or RF sensors was conducted in 1982. The study concluded that video was the most attractive sensor (the video also could be used for operator monitoring). The RetroReflector field Tracker from the Solar Array Flight Experiment was chosen as a 'first generation' sensor and integrated with guidance algorithms for evaluation on the airbearing vehicle. Results indicated that this sensor was not applicable for the noise environment posed by the multilayer insulation used on most spacecraft. A 'second generation' sensor was developed to be used with a modified RMS target. This sensor utilized two sets of laser diodes to acquire three optically filtered targets. The targets were illuminated first with a 780 nanometer diode, followed by illumination with a 830 nm diode. The second digitized picture was subtracted from the first to get a lownoise image. The centroids of the retroreflectors were used then to uniquely derive target attitude and range. The sensor presently operates to 80 feet and within +/ 40 degrees in pitch and yaw. Sensor operability is a concern if the sun is within a +/ 40 degree cone angle to the target. The present sensor performance characteristics are less than 1 percent range error and less than 1 degree angle error. Future sensor development is anticipated to extend the operating range to 150 feet and reduce the cone angle of sensor inoperability to within +/ 10 degrees of direct sunlight. Performance improvements also are anticipated. TRW currently is developing a system that utilizes dual cameras with simultaneous diode illumination. Although further development is being pursued, the basic system has proven sound, and the sensor is essentially ready for application.

Spatial Differencing and Mesh Sensitivity in Two and ThreeDimensional Discrete Ordinates Codes
SciTech Connect
C.S. Davidson; C.A. Burre
20021011
Errors due to spatial differencing methods and mesh size in twodimensional and threedimensional discrete ordinate solutions of a typical gamma ray shielding problem are illustrated by comparing results from the DORT, TORT, and PARTISN codes. using a model geometry that is typical of spent fuel transfer and storage casks these errors were systematically investigated by varying the mesh size and differencing method. The results of this study show that the fixedweighted and adaptive weighted diamond differencing methods in 2D problems require mesh intervals of about 0.25 mfp's for reasonable accuracy in deep penetration. The number of mesh cells required for weighted diamond difference methods severely limit the size of 3D problems that can be solved. The linear discontinuous method in PARTISN is shown to maintain numerical accuracy in 3D problems while reducing the overall computational effort by allowing larger mesh intervals. it is also shown that 3D problems exhibit differencing errors that may not readily be inferred from 2D results. Comprehensive displays of the magnitudes of spatial differencing errors in a practical shielding problem provide valuable guidance for the shielding practitioner using today's computational tools.

Discreteness inducing coexistence
NASA Astrophysics Data System (ADS)
dos Santos, Renato Vieira
20131201
Consider two species that diffuse through space. Consider further that they differ only in initial densities and, possibly, in diffusion constants. Otherwise they are identical. What happens if they compete with each other in the same environment? What is the influence of the discrete nature of the interactions on the final destination? And what are the influence of diffusion and additive fluctuations corresponding to random migration and immigration of individuals? This paper aims to answer these questions for a particular competition model that incorporates intra and interspecific competition between the species. Based on mean field theory, the model has a stationary state dependent on the initial density conditions. We investigate how this initial density dependence is affected by the presence of demographic multiplicative noise and additive noise in space and time. There are three main conclusions: (1) Additive noise favors denser populations at the expense of the less dense, ratifying the competitive exclusion principle. (2) Demographic noise, on the other hand, favors less dense populations at the expense of the denser ones, inducing equal densities at the quasistationary state, violating the aforementioned principle. (3) The slower species always suffers the more deleterious effects of statistical fluctuations in a homogeneous medium.

Anomalous discrete symmetry
SciTech Connect
Huang, Z. )
19921201
We examine an interesting scenario to solve the domainwall problem recently suggested by Preskill, Trivedi, Wilczek, and Wise. The effective potential is calculated in the presence of the QCD axial anomaly. It is shown that some discrete symmetries such as {ital CP} and {ital Z}{sub 2} can be anomalous due to a socalled {ital K} term induced by instantons. We point out that the {ital Z}{sub 2} domainwall problem in the twodoublet standard model can be resolved by two types of solutions: the {ital CP}conserving one and the {ital CP}breaking one. In the first case, there exist two {ital Z}{sub 2}related local minima whose energy splitting is provided by the instanton effect. In the second case, there is only one unique vacuum so that the domain walls do not form at all. The consequences of this new source of {ital CP} violation are discussed and shown to be well within the experimental limits in weak interactions.

Discrete subaortic stenosis.
PubMed Central
Khan, M M; Varma, M P; Cleland, J; O'Kane, H O; Webb, S W; Mulholland, H C; Adgey, A A
19810101
Data concerning 17 consecutive patients with discrete subaortic stenosis are recorded. Twelve patients underwent operative resection of the obstructing lesion. Of these all except one were symptomatic and all had electrocardiographic evidence of left ventricular hypertrophy or left ventricular hypertrophy with strain. They had a peak resting systolic left ventricular outflow tract gradient of greater than 50 mmHg as predicted from the combined cuff measurement of systolic blood pressure and the echocardiographically estimated left ventricular systolic pressure and/or as determined by cardiac catheterisation. The outflow tract gradient as predicted from Mmode echocardiography and peak systolic pressure showed close correlation with that measured at cardiac catheterisation or operation. During the postoperative followup from one month to 11 years, of 11 patients, one patient required a further operation for recurrence of the obstruction four years after the initial operation. All patients are now asymptomatic. Five patients have not had an operation. The left ventricular outflow tract gradient as assessed at the time of cardiac catheterisation was greater than 50 mmHg. One patient has been lost to followup. The remaining four have been followed from four to eight years and have remained asymptomatic and the electrocardiograms have remained unchanged. Careful followup of all patients is essential with continuing clinical assessment, electrocardiograms, Mmode and twodimensional echocardiograms, and if necessary cardiac catheterisation. Prophylaxis against bacterial endocarditis is also essential. Images PMID:6457617

GUIDANCE DOCUMENT ON ENVIRONMENTAL MODELS
EPA Science Inventory
This guidance provides recommendations intended to assist in the development, evaluation and application of high quality environmental models that the Environmental Protection Agency uses to address environmental problems and to support regulatory activities. These guidelines wi...

Discrete neural dynamic programming in wheeled mobile robot control
NASA Astrophysics Data System (ADS)
Hendzel, Zenon; Szuster, Marcin
20110501
In this paper we propose a discrete algorithm for a tracking control of a twowheeled mobile robot (WMR), using an advanced Adaptive Critic Design (ACD). We used DualHeuristic Programming (DHP) algorithm, that consists of two parametric structures implemented as Neural Networks (NNs): an actor and a critic, both realized in a form of Random Vector Functional Link (RVFL) NNs. In the proposed algorithm the control system consists of the DHP adaptive critic, a PD controller and a supervisory term, derived from the Lyapunov stability theorem. The supervisory term guaranties a stable realization of a tracking movement in a learning phase of the adaptive critic structure and robustness in face of disturbances. The discrete tracking control algorithm works online, uses the WMR model for a state prediction and does not require a preliminary learning. Verification has been conducted to illustrate the performance of the proposed control algorithm, by a series of experiments on the WMR Pioneer 2DX.

Guidance for identifying, reporting and tracking nuclear safety noncompliances
SciTech Connect
19951201
This document provides Department of Energy (DOE) contractors, subcontractors and suppliers with guidance in the effective use of DOE`s PriceAnderson nuclear safety Noncompliance Tracking System (NTS). Prompt contractor identification, reporting to DOE, and correction of nuclear safety noncompliances provides DOE with a basis to exercise enforcement discretion to mitigate civil penalties, and suspend the issuance of Notices of Violation for certain violations. Use of this reporting methodology is elective by contractors; however, this methodology is intended to reflect DOE`s philosophy on effective identification and reporting of nuclear safety noncompliances. To the extent that these expectations are met for particular noncompliances, DOE intends to appropriately exercise its enforcement discretion in considering whether, and to what extent, to undertake enforcement action.

Optical Kalman filtering for missile guidance
NASA Technical Reports Server (NTRS)
Casasent, D.; Neuman, C. P.; Lycas, J.
19840101
Optical systolic array processors constitute a powerful and generalpurpose set of optical architectures with high computational rates. In this paper, Kalman filtering, a novel application for these architectures, is investigated. All required operations are detailed; their realization by optical and specialpurpose analog electronics are specified; and the processing time of the system is quantified. The specific Kalman filter application chosen is for an airtoair missile guidance controller. The architecture realized in this paper meets the design goal of a fully adaptive Kalman filter which processes a measurement every 1 msec. The vital issue of flow and pipelining of data and operations in a systolic array processor is addressed. The approach is sufficiently general and can be realized on an optical or digital systolic array processor.

The discrete variational derivative method based on discrete differential forms
NASA Astrophysics Data System (ADS)
Yaguchi, Takaharu; Matsuo, Takayasu; Sugihara, Masaaki
20120501
As is well known, for PDEs that enjoy a conservation or dissipation property, numerical schemes that inherit this property are often advantageous in that the schemes are fairly stable and give qualitatively better numerical solutions in practice. Lately, Furihata and Matsuo have developed the socalled “discrete variational derivative method” that automatically constructs energy preserving or dissipative finite difference schemes. Although this method was originally developed on uniform meshes, the use of nonuniform meshes is of importance for multidimensional problems. On the other hand, the theories of discrete differential forms have received much attention recently. These theories provide a discrete analogue of the vector calculus on general meshes. In this paper, we show that the discrete variational derivative method and the discrete differential forms by Bochev and Hyman can be combined. Applications to the CahnHilliard equation and the KleinGordon equation on triangular meshes are provided as demonstrations. We also show that the schemes for these equations are H1stable under some assumptions. In particular, one for the nonlinear KleinGordon equation is obtained by combination of the energy conservation property and the discrete Poincaré inequality, which are the temporal and spacial structures that are preserved by the above methods.

Resources for Guidance Program Improvement. Volume 2.
ERIC Educational Resources Information Center
Frenza, Mary C., Comp.; and Others
This guide, for guidance personnel and teachers, is designed to provide ready access to current, practical programs, activities, and references for improving guidance programs. The resources are organized in four sections representing areas of basic concern for guidance personnel. Section 1 presents selected portions of guidance programs from…

Information Paper 18: Guidance in Secondary Schools.
ERIC Educational Resources Information Center
Ashton, Terry
19860101
Traces impetus for introduction of structured guidance into Scottish secondary schools. Identifies 1968 "Orange Paper" as first attempt to set out rationale for guidance. Describes how guidance is organized; outlines tasks of guidance teachers; and presents current developments, training requirements, and trends. (NEC)

Books for Professionals: Discipline and Guidance.
ERIC Educational Resources Information Center
King, Margaret A.
19940101
Reviews two books that promote a view of discipline as teaching and guidance. "Guiding Young Children" (Verna Hildebrand) offers specific child guidance techniques and a discussion of general issues affecting child guidance. "Constructive Guidance and Discipline: Preschool and Primary Education" (Majorie V. Fields and Cindy Boesser) focuses on…

Measuring Client Progression in Adult Guidance
ERIC Educational Resources Information Center
Hearne, Lucy
20070101
Currently, in the field of guidance, relevant stakeholders including guidance practitioners, educators and policy makers, have identified progression for adults in education and employment as one of the key outcomes of educational guidance. Lifelong guidance is now inextricably linked with lifelong learning as a mechanism to enhance individual…

Exact discretization by Fourier transforms
NASA Astrophysics Data System (ADS)
Tarasov, Vasily E.
20160801
A discretization of differential and integral operators of integer and noninteger orders is suggested. New type of differences, which are represented by infinite series, is proposed. A characteristic feature of the suggested differences is an implementation of the same algebraic properties that have the operator of differentiation (property of algebraic correspondence). Therefore the suggested differences are considered as an exact discretization of derivatives. These differences have a property of universality, which means that these operators do not depend on the form of differential equations and the parameters of these equations. The suggested differences operators allows us to have difference equations whose solutions are equal to the solutions of corresponding differential equations. The exact discretization of the derivatives of integer orders is given by the suggested differences of the same integer orders. Similarly, the exact discretization of the Riesz derivatives and integrals of integer and noninteger order is given by the proposed fractional differences of the same order.

Novel approach to data discretization
NASA Astrophysics Data System (ADS)
Borowik, Grzegorz; Kowalski, Karol; Jankowski, Cezary
20150901
Discretization is an important preprocessing step in data mining. The data discretization method involves determining the ranges of values for numeric attributes, which ultimately represent discrete intervals for new attributes. The ranges for the proposed set of cuts are analyzed, in order to obtain a minimal set of ranges while retaining the possibility of classification. For this purpose, a special discernibility function can be constructed as a conjunction of alternative cuts set for each pair of different objects of different decisions cuts discern these objects. However, the data mining methods based on discernibility matrix are insufficient for large databases. The purpose of this paper is the idea of implementation of a new data discretization algorithm that is based on statistics of attribute values and that avoids building the discernibility matrix explicitly. Evaluation of time complexity has shown that the proposed method is much more efficient than currently available solutions for large data sets.

Chaos in Periodic Discrete Systems
NASA Astrophysics Data System (ADS)
Shi, Yuming; Zhang, Lijuan; Yu, Panpan; Huang, Qiuling
This paper focuses on chaos in periodic discrete systems, whose state space may vary with time. Some close relationships between some chaotic dynamical behaviors of a periodic discrete system and its autonomous induced system are given. Based on these relationships, several criteria of chaos are established and some sufficient conditions for no chaos are given for periodic discrete systems. Further, it is shown that a finitedimensional linear periodic discrete system is not chaotic in the sense of LiYorke or Wiggins. In particular, an interesting problem of whether nonchaotic rules may generate a chaotic system is studied, with some examples provided, one of which surprisingly shows that a composition of globally asymptotically stable maps can be chaotic. In addition, some properties of sign pattern matrices of nonnegative square matrices are given for convenience of the study.

Microscopic derivation of discrete hydrodynamics.
PubMed
Español, Pep; Anero, Jesús G; Zúñiga, Ignacio
20091228
By using the standard theory of coarse graining based on Zwanzig's projection operator, we derive the dynamic equations for discrete hydrodynamic variables. These hydrodynamic variables are defined in terms of the Delaunay triangulation. The resulting microscopically derived equations can be understood, a posteriori, as a discretization on an arbitrary irregular grid of the NavierStokes equations. The microscopic derivation provides a set of discrete equations that exactly conserves mass, momentum, and energy and the dissipative part of the dynamics produces strict entropy increase. In addition, the microscopic derivation provides a practical implementation of thermal fluctuations in a way that the fluctuationdissipation theorem is satisfied exactly. This paper points toward a close connection between coarsegraining procedures from microscopic dynamics and discretization schemes for partial differential equations. PMID:20059064

Information architecture. Volume 3: Guidance
SciTech Connect
19970401
The purpose of this document, as presented in Volume 1, The Foundations, is to assist the Department of Energy (DOE) in developing and promulgating information architecture guidance. This guidance is aimed at increasing the development of information architecture as a Departmentwide management best practice. This document describes departmental information architecture principles and minimum design characteristics for systems and infrastructures within the DOE Information Architecture Conceptual Model, and establishes a Departmentwide standardsbased architecture program. The publication of this document fulfills the commitment to address guiding principles, promote standard architectural practices, and provide technical guidance. This document guides the transition from the baseline or defacto Departmental architecture through approved information management program plans and budgets to the future vision architecture. This document also represents another major step toward establishing a wellorganized, logical foundation for the DOE information architecture.

Small Body GN&C Research Report: A GGuidance Enhancement to Increase Mission Functionality
NASA Technical Reports Server (NTRS)
Carson, John M., III; Ackmese, Behcet
20060101
GGuidance is a robust G&C (guidance and control) algorithm developed under the smallbody GN&C task. The GGuidance scheme utilizes a model predictive control approach, along with a convexification of the governing dynamics, control constraints, and trajectory/state constraints. This report details an enhancement to the FY2005 GGuidance algorithm; the addition of a firesecond approach helps to nullify velocity errors and hit desired final velocities much more precisely than the original Firefirst scheme developed in FY2005. The enhancement preserves the primary benefit of the algorithm, which is to ensure required thruster silent times during trajectory maneuvers. The firesecond scheme increases the versatility of the algorithm for missions employing GGuidance. For instance, a landing sequence could employ the firesecond scheme to ensure a null final velocity at landing, whereas an ascent sequence could utilize a firefirst scheme to ensure there is no drift of the spacecraft toward the ground at the beginning of the maneuver. Examples are provided within to demonstrate a firefirst versus firesecond guidance scheme. As in the existing GGuidance algorithm, the examples and schemes incorporate gravity models and thruster firing times into discrete dynamics that are solved as a optimal control problem to minimize fuel consumption or thruster energy expenditure.

Guidance for state attainment plans
SciTech Connect
Strait, R.
19940601
Title I of the Clean Air act Amendments of 1990 significantly changed requirements for regulatory agencies to prepare state implementation plans that demonstrate attainment of the ozone National Ambient Air Quality Standards. State agencies now are required to submit plans that show how they will meet the standards by their attainment date. EPA has published a series of guidance documents to assist states in preparing their plans. In addition, the agency is developing software to assist states in projecting emissions and tracking reductions. This article summarizes the guidance documents and software program.

Anomaly Detection for Discrete Sequences: A Survey
SciTech Connect
Chandola, Varun; Banerjee, Arindam; Kumar, Vipin
20120101
This survey attempts to provide a comprehensive and structured overview of the existing research for the problem of detecting anomalies in discrete/symbolic sequences. The objective is to provide a global understanding of the sequence anomaly detection problem and how existing techniques relate to each other. The key contribution of this survey is the classification of the existing research into three distinct categories, based on the problem formulation that they are trying to solve. These problem formulations are: 1) identifying anomalous sequences with respect to a database of normal sequences; 2) identifying an anomalous subsequence within a long sequence; and 3) identifying a pattern in a sequence whose frequency of occurrence is anomalous. We show how each of these problem formulations is characteristically distinct from each other and discuss their relevance in various application domains. We review techniques from many disparate and disconnected application domains that address each of these formulations. Within each problem formulation, we group techniques into categories based on the nature of the underlying algorithm. For each category, we provide a basic anomaly detection technique, and show how the existing techniques are variants of the basic technique. This approach shows how different techniques within a category are related or different from each other. Our categorization reveals new variants and combinations that have not been investigated before for anomaly detection. We also provide a discussion of relative strengths and weaknesses of different techniques. We show how techniques developed for one problem formulation can be adapted to solve a different formulation, thereby providing several novel adaptations to solve the different problem formulations. We also highlight the applicability of the techniques that handle discrete sequences to other related areas such as online anomaly detection and time series anomaly detection.

Distributed Adaptive Control: Beyond SingleInstant, Discrete Variables
NASA Technical Reports Server (NTRS)
Wolpert, David H.; Bieniawski, Stefan
20050101
In extensive form noncooperative game theory, at each instant t, each agent i sets its state x, independently of the other agents, by sampling an associated distribution, q(sub i)(x(sub i)). The coupling between the agents arises in the joint evolution of those distributions. Distributed control problems can be cast the same way. In those problems the system designer sets aspects of the joint evolution of the distributions to try to optimize the goal for the overall system. Now information theory tells us what the separate q(sub i) of the agents are most likely to be if the system were to have a particular expected value of the objective function G(x(sub 1),x(sub 2), ...). So one can view the job of the system designer as speeding an iterative process. Each step of that process starts with a specified value of E(G), and the convergence of the q(sub i) to the most likely set of distributions consistent with that value. After this the target value for E(sub q)(G) is lowered, and then the process repeats. Previous work has elaborated many schemes for implementing this process when the underlying variables x(sub i) all have a finite number of possible values and G does not extend to multiple instants in time. That work also is based on a fixed mapping from agents to control devices, so that the the statistical independence of the agents' moves means independence of the device states. This paper also extends that work to relax all of these restrictions. This extends the applicability of that work to include continuous spaces and Reinforcement Learning. This paper also elaborates how some of that earlier work can be viewed as a firstprinciples justification of evolutionbased search algorithms.

Identification of micro parameters for discrete element simulation of agglomerates
NASA Astrophysics Data System (ADS)
Palis, Stefan; Antonyuk, Sergiy; Dosta, Maksym; Heinrich, Stefan
20130601
The mechanical behaviour of solid particles like agglomerates, granules or crystals strongly depends on their micro structure, e.g. structural defects and porosity. In order to model the mechanical behaviour of these inhomogeneous media the discrete element method has been proven to be an appropriate tool. The model parameters used are typically micro parameters like bond stiffness, particleparticle contact stiffness, strength of the bonds. Due to the lack of general methods for a direct micro parameter determination, normally laborious parameter adaptation has to be done in order to fit experiment and simulation. In this contribution a systematic and automatic way for parameter adaptation using real experiments is proposed. Due to the fact, that discrete element models are typically systems of differential equations of very high order, gradient based methods are not suitable. Hence, the focus will be on derivative free methods.

Distributed Relaxation for Conservative Discretizations
NASA Technical Reports Server (NTRS)
Diskin, Boris; Thomas, James L.
20010101
A multigrid method is defined as having textbook multigrid efficiency (TME) if the solutions to the governing system of equations are attained in a computational work that is a small (less than 10) multiple of the operation count in one targetgrid residual evaluation. The way to achieve this efficiency is the distributed relaxation approach. TME solvers employing distributed relaxation have already been demonstrated for nonconservative formulations of highReynoldsnumber viscous incompressible and subsonic compressible flow regimes. The purpose of this paper is to provide foundations for applications of distributed relaxation to conservative discretizations. A direct correspondence between the primitive variable interpolations for calculating fluxes in conservative finitevolume discretizations and stencils of the discretized derivatives in the nonconservative formulation has been established. Based on this correspondence, one can arrive at a conservative discretization which is very efficiently solved with a nonconservative relaxation scheme and this is demonstrated for conservative discretization of the quasi onedimensional Euler equations. Formulations for both staggered and collocated grid arrangements are considered and extensions of the general procedure to multiple dimensions are discussed.

Theater As A Guidance Technique
ERIC Educational Resources Information Center
Wolpert, William
19730101
Guidancedrama activity provides (a) crisp definitions of selected issues; (b) potent modeling from the characters in the play, the students actively engaged in the play, and the students involved in the discussions that follow the play; and (c) a technique for peerled discussions on sensitive issues. This article gives precise definition to the…

Humanizing Education Through Guidance Counseling.
ERIC Educational Resources Information Center
Accola, W. V.
A computerized information retrieval system has been designed to support the secondary school counseling effort. The system, entitled Total Guidance Information Support System (TGISS), runs on an IBM System/360 Model 65 facility and uses the IBM 2848 Display Control Unit. The software consists of an interactive communications program developed in…

THE STRESSOR IDENTIFICATION GUIDANCE DOCUMENT
EPA Science Inventory
THE STRESSOR IDENTIFICATION GUIDANCE DOCUMENT
Susan M. Cormier, ORD/NRMRL, Susan B. Norton, ORD/NCEA, Glenn W. Suter, II ORD/NCEA, William Swietlik, OW lOST
Science Question(s):
MYP Science Question: How can multiple and possibly related causes of biological ...

Reading Guidance: Death and Grief.
ERIC Educational Resources Information Center
Smith, Alice Gullen
19890101
Gives guidelines for the librarian using reading guidance (similar to bibliotherapy). Provides a nineitem annotated bibliography of novels for children and adolescents on the subject of death and grief. Appends an embryo list of categories suitable for content analysis of any file librarians might wish to keep on books suitable for use in this…

The revised HSE fatigue guidance
SciTech Connect
Stacey, A.; Sharp, J.V.
19951231
Fatigue cracking has been a principal cause of damage to North Sea structures and consequently considerable attention has been given to the development of guidance for the prediction of fatigue performance. The fatigue guidance of the Offshore Safety Division of the Health and Safety Executive (HSE) was recently revised and published, following a significant offshore industry review in the period 1987 to 1990, and is based on the results of a considerable amount of research and development work on the fatigue behavior of welded tubular and plated joints. As a result of this review, the revised fatigue guidance incorporates several new clauses and recommendations. The revised recommendations apply to joint classification, basic design SN curves for welded joints and cast or forged steel components, the thickness effect, the effects of environment and the treatment of low and high stress ranges. Additionally, a new appendix on the derivation of stress concentration factors is included. The new clauses cover high strength steels, bolts and threaded connectors, moorings, repaired joints and the use of fracture mechanics analysis. This paper presents an overview of the revisions to the fatigue guidance, the associated background technical information and aspects of the fatigue behavior of offshore structures which are considered to require further investigation. 67 refs., 7 figs., 8 tabs.

Career Guidance in Singapore Schools.
ERIC Educational Resources Information Center
Tan, Esther
20020101
Reviews the history and stages of development for career guidance in Singapore schools. Asserts that to meet the challenges of the new millennium, there is a need to train professional career counselors, develop indigenous resource materials, and promote a new concept of career development among students. (Contains 15 references.) (GCP)

Developing Local Lifelong Guidance Strategies.
ERIC Educational Resources Information Center
Watts, A. G.; Hawthorn, Ruth; Hoffbrand, Jill; Jackson, Heather; Spurling, Andrea
19970101
Outlines the background, rationale, methodology, and outcomes of developing local lifelong guidance strategies in four geographic areas. Analyzes the main components of the strategies developed and addresses a number of issues relating to the process of strategy development. Explores implications for parallel work in other localities. (RJM)

On the Importance of the Dynamics of Discretizations
NASA Technical Reports Server (NTRS)
Sweby, Peter K.; Yee, H. C.; Rai, ManMohan (Technical Monitor)
19950101
It has been realized recently that the discrete maps resulting from numerical discretizations of differential equations can possess asymptotic dynamical behavior quite different from that of the original systems. This is the case not only for systems of Ordinary Differential Equations (ODEs) but in a more complicated manner for Partial Differential Equations (PDEs) used to model complex physics. The impact of the modified dynamics may be mild and even not observed for some numerical methods. For other classes of discretizations the impact may be pronounced, but not always obvious depending on the nonlinear model equations, the time steps, the grid spacings and the initial conditions. Nonconvergence or convergence to periodic solutions might be easily recognizable but convergence to incorrect but plausible solutions may not be so obvious  even for discretized parameters within the linearized stability constraint. Based on our past four years of research, we will illustrate some of the pathology of the dynamics of discretizations, its possible impact and the usage of these schemes for model nonlinear ODEs, convectiondiffusion equations and grid adaptations.

Pinning synchronization of discrete dynamical networks with delay coupling
NASA Astrophysics Data System (ADS)
Cheng, Ranran; Peng, Mingshu; Zuo, Jun
20160501
The purpose of this paper is to investigate the pinning synchronization analysis for nonlinear coupled delayed discrete dynamical networks with the identical or nonidentical topological structure. Based on the Lyapunov stability theory, pinning control method and linear matrix inequalities, several adaptive synchronization criteria via two kinds of pinning control method are obtained. Two examples based on Rulkov chaotic system are included to illustrate the effectiveness and verification of theoretical analysis.

Discretion or discretions? Delineating professional discretion: the case of English medical practice.
PubMed
CheraghiSohi, Sudeh; Calnan, Michael
20131101
There has much debate about the extent to which professional discretion has been challenged by recent organisational changes such as through the new forms of governance associated with the introduction of the principles of the New Public Management (NPM) into health systems and other public sector services. What appears to be missing from these debates is a detailed analysis of the concept of professional discretion itself. This paper attempts to fill this gap by delineating the key concepts of professional discretion evident in the literature and exploring their significance in an empirical study of the influence of the 2004 new general medical services contract (nGMS) and the introduction of the Quality and Outcomes Framework (QOF), a prescriptive payforperformance system designed to standardise the quality of care provision in general medical practice in the United Kingdom. The study adopted a longitudinal design using semistructured interviews with general practitioners (GPs, N = 62) working in the English National Health Service (NHS) between 2007 and 2009. A multidimensional conception of discretion was used to explore how GP discretion might have been influenced by contractual changes and in particular, QOF. The findings suggest that through a complex interplay of factors, a postQOF reduction in GP discretion was identifiable, highlighting different potential sources of constraint such as in the social, organisational and economic dimensions of discretion. The evidence also suggested the emergence of a new form of organisational medical professionalism within general practice characterised by standardisation, bureaucracy and performance management. PMID:24034951

A new paradigm in optimal missile guidance
NASA Astrophysics Data System (ADS)
Morgan, Robert W.
20071201
This dissertation investigates advanced concepts in terminal missile guidance. The terminal phase of missile guidance usually lasts less than ten seconds and calls for very accurate maneuvering to ensure intercept. Technological advancements have produced increasingly sophisticated threats that greatly reduce the effectiveness of traditional approaches to missile guidance. Because of this, terminal missile guidance is, and will remain, an important and active area of research. The complexity of the problem and the desire for an optimal solution has resulted in researchers focusing on simplistic, usually linear, models. The fruit of these endeavors has resulted in some of the world's most advanced weapons systems. Even so, the resulting guidance schemes cannot possibly counter the evolving threats that will push the system outside the linear envelope for which they were designed. The research done in this dissertation greatly extends previous research in the area of optimal missile guidance. Herein it is shown that optimal missile guidance is fundamentally a pairing of an optimal guidance strategy and an optimal control strategy. The optimal guidance strategy is determined from a missile's information constraints, which are themselves largely determined from the missile's sensors. The optimal control strategy is determined by the missile's control constraints, and works to achieve a specified guidance strategy. This dichotomy of missile guidance is demonstrated by showing that missiles having different control constraints utilize the same guidance strategy so long as the information constraints are the same. This concept has hitherto been unrecognized because of the difficulty in developing an optimal control for the nonlinear set of equations that result from control constraints. Having overcome this difficulty by indirect means, evidence of the guidance strategy paradigm emerged. The guidance strategy paradigm is used to develop two advanced guidance laws. The new

Geometry of discrete quantum computing
NASA Astrophysics Data System (ADS)
Hanson, Andrew J.; Ortiz, Gerardo; Sabry, Amr; Tai, YuTsung
20130501
Conventional quantum computing entails a geometry based on the description of an nqubit state using 2n infinite precision complex numbers denoting a vector in a Hilbert space. Such numbers are in general uncomputable using any realworld resources, and, if we have the idea of physical law as some kind of computational algorithm of the universe, we would be compelled to alter our descriptions of physics to be consistent with computable numbers. Our purpose here is to examine the geometric implications of using finite fields Fp and finite complexified fields \\mathbf {F}_{p^2} (based on primes p congruent to 3 (mod4)) as the basis for computations in a theory of discrete quantum computing, which would therefore become a computable theory. Because the states of a discrete nqubit system are in principle enumerable, we are able to determine the proportions of entangled and unentangled states. In particular, we extend the Hopf fibration that defines the irreducible state space of conventional continuous nqubit theories (which is the complex projective space \\mathbf {CP}^{2^{n}1}) to an analogous discrete geometry in which the Hopf circle for any n is found to be a discrete set of p + 1 points. The tally of unitlength nqubit states is given, and reduced via the generalized Hopf fibration to \\mathbf {DCP}^{2^{n}1}, the discrete analogue of the complex projective space, which has p^{2^{n}1} (p1)\\,\\prod _{k=1}^{n1} ( p^{2^{k}}+1) irreducible states. Using a measure of entanglement, the purity, we explore the entanglement features of discrete quantum states and find that the nqubit states based on the complexified field \\mathbf {F}_{p^2} have pn(p  1)n unentangled states (the product of the tally for a single qubit) with purity 1, and they have pn + 1(p  1)(p + 1)n  1 maximally entangled states with purity zero.

Engineering Guidance: A Human Resource Development.
ERIC Educational Resources Information Center
Snarponis, Joseph M.; Prien, John D.
19790101
Describes the role of The National Society of Professional Engineers (NSPE) in providing guidance activities for students. Discusses structional organization, goals, and guidance activities for engineering and technical and professional societies. (MA)

Activity Group Guidance: A Developmental Approach
ERIC Educational Resources Information Center
Hillman, Bill W.; And Others
19750101
Illustrates the content, process, and group dynamics of Activity Group Guidance. Describes and evaluates a comprehensive Activity Group Guidance program. Gives specific suggestions to counselors who wish to start Activity Groups. (Author)

HODIF:HighOrder Discretizations, Interpolations and
SciTech Connect
Kennedy, Christopher A.; Carpenter, Mark H.; Ray, Jaideen
20060620
This software, a library, contains FORTRAN77 subroutines to calculate first and second derivatives up to 8th order, interpolations (1D and 2D) up to 10th order and filters up to 14th order. Only even orders are addressed and finitedifference stencils are implemented on a vertexcentered mesh. The primary aim of this library is to be used in blockstructured adaptive mesh simulations where high order is desired. The interpolants in this library are essentially designed to do prolongations and restrictions between levels of rfinement  however, they assume that the refinement ratio is 2. The filters are provided to remove high wavenumber content from solutions in case Runge phenomenon occurs  a common occurrence in case of marginal resolution of the solution. Details of the derivation and use are to be found in "Using highorder methods on adaptively refined blockstructured meshes  discretizations, interpolations and filters", by J. Ray, C.A. Kennedy, S. Lefantzi and H.N. Najm, Sandia Technical Report, SAND20057981. The software comes with a User's Guide and examples how to use it.

HODIF:HighOrder Discretizations, Interpolations and
Energy Science and Technology Software Center (ESTSC)
20060620
This software, a library, contains FORTRAN77 subroutines to calculate first and second derivatives up to 8th order, interpolations (1D and 2D) up to 10th order and filters up to 14th order. Only even orders are addressed and finitedifference stencils are implemented on a vertexcentered mesh. The primary aim of this library is to be used in blockstructured adaptive mesh simulations where high order is desired. The interpolants in this library are essentially designed to domore » prolongations and restrictions between levels of rfinement  however, they assume that the refinement ratio is 2. The filters are provided to remove high wavenumber content from solutions in case Runge phenomenon occurs  a common occurrence in case of marginal resolution of the solution. Details of the derivation and use are to be found in "Using highorder methods on adaptively refined blockstructured meshes  discretizations, interpolations and filters", by J. Ray, C.A. Kennedy, S. Lefantzi and H.N. Najm, Sandia Technical Report, SAND20057981. The software comes with a User's Guide and examples how to use it.« less

Fourdimensional guidance problem with control delays. [in air traffic control automation
NASA Technical Reports Server (NTRS)
Nagarajan, N.
19760101
This paper, assuming steady wind and zero sideslip, presents a discretetime mathematical model to obtain a control law and threedimensional flight path to guide an aircraft in a given time from a given initial state (position, velocity and heading) to a prescribed final state subject to the constraints on airspeed acceleration, and pitch and bank angles of the aircraft. For ease in implementing the control law, the control inputs are assumed to be delayed and are applied in a sequential fashion. The guidance problem is formulated as a discrete nonlinear optimal control problem with time delays in dynamics and a cost functional of Bolza form. With a quadratic penalty function to handle terminal constraints on velocity and heading, a solution technique to the control problem based on conjugate gradient algorithm is investigated. Numerical examples are presented to illustrate the applicability of this approach to solution of a terminal area guidance problem in an automated air traffic control environment.

Quality Assurance in University Guidance Services
ERIC Educational Resources Information Center
Simon, Alexandra
20140101
In Europe there is no common quality assurance framework for the delivery of guidance in higher education. Using a case study approach in four university career guidance services in England, France and Spain, this article aims to study how quality is implemented in university career guidance services in terms of strategy, standards and models,…

Idaho Comprehensive Guidance and Counseling Program Model.
ERIC Educational Resources Information Center
Idaho State Dept. of Education, Boise.
This handbook describes a series of procedures for establishing school guidance and counseling programs in Idaho based on the Missouri Comprehensive Guidance Program model developed by Dr. Norman Gysbers. It begins with a conceptual framework and moves through the development, evaluation, and refinement steps of setting guidance programs in Idaho…

ComputerAssisted Guidance: Concepts and Practices.
ERIC Educational Resources Information Center
Katz, Martin R.; Shatkin, Laurence
This report reviews and analyzes the development and status of computerassistedguidance (CAG) systems. In terms of eight major topics which are introduced in a discussion of guidance and the computer, the report discusses the capabilities of computers in reference to other resources for guidance and describes and differentiates various CAG…

Reduced discretization error in HZETRN
SciTech Connect
Slaba, Tony C.; Blattnig, Steve R.; Tweed, John
20130201
The deterministic particle transport code HZETRN is an efficient analysis tool for studying the effects of space radiation on humans, electronics, and shielding materials. In a previous work, numerical methods in the code were reviewed, and new methods were developed that further improved efficiency and reduced overall discretization error. It was also shown that the remaining discretization error could be attributed to low energy light ions (A < 4) with residual ranges smaller than the physical stepsize taken by the code. Accurately resolving the spectrum of low energy light particles is important in assessing risk associated with astronaut radiation exposure. In this work, modifications to the light particle transport formalism are presented that accurately resolve the spectrum of low energy light ion target fragments. The modified formalism is shown to significantly reduce overall discretization error and allows a physical approximation to be removed. For typical stepsizes and energy grids used in HZETRN, discretization errors for the revised light particle transport algorithms are shown to be less than 4% for aluminum and water shielding thicknesses as large as 100 g/cm{sup 2} exposed to both solar particle event and galactic cosmic ray environments.

Some discrete multiple orthogonal polynomials
NASA Astrophysics Data System (ADS)
Arvesú, J.; Coussement, J.; van Assche, W.
20030401
In this paper, we extend the theory of discrete orthogonal polynomials (on a linear lattice) to polynomials satisfying orthogonality conditions with respect to r positive discrete measures. First we recall the known results of the classical orthogonal polynomials of Charlier, Meixner, Kravchuk and Hahn (T.S. Chihara, An Introduction to Orthogonal Polynomials, Gordon and Breach, New York, 1978; R. Koekoek and R.F. Swarttouw, Reports of the Faculty of Technical Mathematics and Informatics No. 9817, Delft, 1998; A.F. Nikiforov et al., Classical Orthogonal Polynomials of a Discrete Variable, Springer, Berlin, 1991). These polynomials have a lowering and raising operator, which give rise to a Rodrigues formula, a second order difference equation, and an explicit expression from which the coefficients of the threeterm recurrence relation can be obtained. Then we consider r positive discrete measures and define two types of multiple orthogonal polynomials. The continuous case (Jacobi, Laguerre, Hermite, etc.) was studied by Van Assche and Coussement (J. Comput. Appl. Math. 127 (2001) 317347) and Aptekarev et al. (Multiple orthogonal polynomials for classical weights, manuscript). The families of multiple orthogonal polynomials (of type II) that we will study have a raising operator and hence a Rodrigues formula. This will give us an explicit formula for the polynomials. Finally, there also exists a recurrence relation of order r+1 for these multiple orthogonal polynomials of type II. We compute the coefficients of the recurrence relation explicitly when r=2.

Optical guidance vidicon test program
NASA Technical Reports Server (NTRS)
Eiseman, A. R.; Stanton, R. H.; Voge, C. C.
19760101
A laboratory and field test program was conducted to quantify the optical navigation parameters of the Mariner vidicons. A scene simulator and a camera were designed and built for vidicon tests under a wide variety of conditions. Laboratory tests characterized error sources important to the optical navigation process and field tests verified star sensitivity and characterized comet optical guidance parameters. The equipment, tests and data reduction techniques used are described. Key test results are listed. A substantial increase in the understanding of the use of selenium vidicons as detectors for spacecraft optical guidance was achieved, indicating a reduction in residual offset errors by a factor of two to four to the single pixel level.

Microfluidic control of axonal guidance
NASA Astrophysics Data System (ADS)
Gu, Ling; Black, Bryan; Ordonez, Simon; Mondal, Argha; Jain, Ankur; Mohanty, Samarendra
20141001
The precision of axonal pathfinding and the accurate formation of functional neural circuitry are crucial for an organism during development as well as during adult central and peripheral nerve regeneration. While chemical cues are believed to be primarily responsible for axonal pathfinding, we hypothesize that forces due to localized fluid flow may directly affect neuronal guidance during early organ development. Here, we report direct evidence of fluid flow influencing axonal migration, producing turning angles of up to 90°. Microfluidic flow simulations indicate that an axon may experience significant bending force due to crossflow, which may contribute to the observed axonal turning. This method of flowbased guidance was successfully used to fasciculate one advancing axon onto another, showcasing the potential of this technique to be used for the formation of in vitro neuronal circuits.

Teleautonomous guidance for mobile robots
NASA Technical Reports Server (NTRS)
Borenstein, J.; Koren, Y.
19900101
Teleautonomous guidance (TG), a technique for the remote guidance of fast mobile robots, has been developed and implemented. With TG, the mobile robot follows the general direction prescribed by an operator. However, if the robot encounters an obstacle, it autonomously avoids collision with that obstacle while trying to match the prescribed direction as closely as possible. This type of shared control is completely transparent and transfers control between teleoperation and autonomous obstacle avoidance gradually. TG allows the operator to steer vehicles and robots at high speeds and in cluttered environments, even without visual contact. TG is based on the virtual force field (VFF) method, which was developed earlier for autonomous obstacle avoidance. The VFF method is especially suited to the accommodation of inaccurate sensor data (such as that produced by ultrasonic sensors) and sensor fusion, and allows the mobile robot to travel quickly without stopping for obstacles.

Guidance molecules in lung cancer
PubMed Central
Nasarre, Patrick; Potiron, Vincent; Drabkin, Harry
20100101
Guidance molecules were first described in the nervous system to control axon outgrowth direction. They are also widely expressed outside the nervous system where they control cell migration, tissue development and establishment of the vascular network. In addition, they are involved in cancer development, tumor angiogenesis and metastasis. This review is primarily focused on their functions in lung cancer and their involvement in lung development is also presented. Five guidance molecule families and their corresponding receptors are described, including the semaphorins/neuropilins/plexins, ephrins and Eph receptors, netrin/DCC/UNC5, Slit/Robo and Notch/Delta. In addition, the possibility to target these molecules as a therapeutic approach in cancer is discussed. PMID:20139699

Discrete implementations of scale transform
NASA Astrophysics Data System (ADS)
Djurdjanovic, Dragan; Williams, William J.; Koh, Christopher K.
19991101
Scale as a physical quantity is a recently developed concept. The scale transform can be viewed as a special case of the more general Mellin transform and its mathematical properties are very applicable in the analysis and interpretation of the signals subject to scale changes. A number of singledimensional applications of scale concept have been made in speech analysis, processing of biological signals, machine vibration analysis and other areas. Recently, the scale transform was also applied in multidimensional signal processing and used for image filtering and denoising. Discrete implementation of the scale transform can be carried out using logarithmic sampling and the wellknown fast Fourier transform. Nevertheless, in the case of the uniformly sampled signals, this implementation involves resampling. An algorithm not involving resampling of the uniformly sampled signals has been derived too. In this paper, a modification of the later algorithm for discrete implementation of the direct scale transform is presented. In addition, similar concept was used to improve a recently introduced discrete implementation of the inverse scale transform. Estimation of the absolute discretization errors showed that the modified algorithms have a desirable property of yielding a smaller region of possible error magnitudes. Experimental results are obtained using artificial signals as well as signals evoked from the temporomandibular joint. In addition, discrete implementations for the separable twodimensional direct and inverse scale transforms are derived. Experiments with image restoration and scaling through twodimensional scale domain using the novel implementation of the separable twodimensional scale transform pair are presented.

Mars Science Laboratory Entry Guidance
NASA Technical Reports Server (NTRS)
Mendeck, Gavin F.
20110101
The Mars Science Laboratory will be the first Mars mission to attempt a guided entry with the objective of safely delivering the entry vehicle to a survivable parachute deploy state within 12.5 km of the predesignated parachute deploy coordinates. The Entry Terminal Point Controller guidance algorithm is derived from the final phase Apollo Command Module guidance and, like Apollo, modulates the bank angle to control range based on deviations in range, altitude rate, and drag acceleration from a reference trajectory. For application to Mars landers which must make use of the tenuous Martian atmosphere, it is critical to balance the lift of the vehicle to minimize the range while still ensuring a safe deploy altitude. An overview of the process to generate optimized guidance settings is presented, discussing improvements made over the last nine years. Performance tradeoffs between ellipse size and deploy altitude will be presented, along with imposed constraints of entry acceleration and heating. Performance sensitivities to the bank reversal deadbands, heading alignment, attitude initialization error, and entry delivery errors are presented.

Role of Cell Cycle Regulation and MLH1, A Key DNA Mismatch Repair Protein, In Adaptive Survival Responses. Final Report
SciTech Connect
David A. Boothman
19990811
Due to several interesting findings on both adaptive survival responses (ASRs) and DNA mismatch repair (MMR), this grant was separated into two discrete Specific Aim sets (each with their own discrete hypotheses). The described experiments were simultaneously performed.

Adaptation and risk management
SciTech Connect
Preston, Benjamin L
20110101
Adaptation assessment methods are compatible with the international risk management standard ISO:31000. Risk management approaches are increasingly being recommended for adaptation assessments at both national and local levels. Two orientations to assessments can commonly be identified: topdown and bottomup, and prescriptive and diagnostic. Combinations of these orientations favor different types of assessments. The choice of orientation can be related to uncertainties in prediction and taking action, in the type of adaptation and in the degree of system stress. Adopting multiple viewpoints is to be encouraged, especially in complex situations. The bulk of current guidance material is consistent with topdown and predictive approaches, thus is most suitable for risk scoping and identification. Abroad range ofmaterial fromwithin and beyond the climate change literature can be used to select methods to be used in assessing and implementing adaptation. The framing of risk, correct formulation of the questions being investigated and assessment methodology are critical aspects of the scoping phase. Only when these issues have been addressed should be issue of specific methods and tools be addressed. The reorientation of adaptation from an assessment focused solely on anthropogenic climate change to broader issues of vulnerability/resilience, sustainable development and disaster risk, especially through a risk management framework, can draw from existing policy and management understanding in communities, professions and agencies, incorporating existing agendas, knowledge, risks, and issues they already face.

CREATING INTEROPERABLE MESHING AND DISCRETIZATION SOFTWARE: THE TERASCALE SIMULATION TOOLS AND TECHNOLOGY CENTER.
SciTech Connect
BROWN,D.; FREITAG,L.; GLIMM,J.
20020602
We present an overview of the technical objectives of the Terascale Simulation Tools and Technologies center. The primary goal of this multiinstitution collaboration is to develop technologies that enable application scientists to easily use multiple mesh and discretization strategies within a single simulation on terascale computers. The discussion focuses on our efforts to create interoperable mesh generation tools, highorder discretization techniques, and adaptive meshing strategies.

Creating Interoperable Meshing and Discretization Software: The Terascale Simulation Tools and Technology Center
SciTech Connect
Brown, D.; Freitag, L.; Glimm, J.
20020328
We present an overview of the technical objectives of the Terascale Simulation Tools and Technologies center. The primary goal of this multiinstitution collaboration is to develop technologies that enable application scientists to easily use multiple mesh and discretization strategies within a single simulation on terascale computers. The discussion focuses on our efforts to create interoperable mesh generation tools, highorder discretization techniques, and adaptive meshing strategies.

Dark energy from discrete spacetime.
PubMed
Trout, Aaron D
20130101
Dark energy accounts for most of the matterenergy content of our universe, yet current theories of its origin rely on radical physical assumptions such as the holographic principle or controversial anthropic arguments. We give a better motivated explanation for dark energy, claiming that it arises from a small negative scalarcurvature present even in empty spacetime. The vacuum has this curvature because spacetime is fundamentally discrete and there are more ways for a discrete geometry to have negative curvature than positive. We explicitly compute this effect using a variant of the well known dynamicaltriangulations (DT) model for quantum gravity. Our model predicts a timevarying nonzero cosmological constant with a current value, [Formula: see text] in natural units, in agreement with observation. This calculation is made possible by a novel characterization of the possible DT action values combined with numerical evidence concerning their degeneracies. PMID:24312502

Class of discrete Gabor expansion
NASA Astrophysics Data System (ADS)
Li, Shidong; Healy, Dennis M., Jr.
19940301
We present a new approach to studying a discrete Gabor expansion (DGE). We show that, in general, DGE is not the usual biorthogonal decomposition, but belongs to a larger and looser decomposition scheme which we call pseudo frame decomposition. It includes the DGE scheme proposed as a special case. The standard dual frame decomposition is also a special case. We derive algorithms using techniques for Gabor sequences to compute 'biorthogonal' sequences through proper matrix representation. Our algorithms involve solutions to a linear system to obtain the 'biorthogonal' windows. This approach provides a much broader mathematical view of the DGE, and therefore, establishes a wider mathematical foundation towards the theory of DGE. The general algorithm derived also provides a whole class of discrete Gabor expansions, among which 'good' ones can be generated. Simulation results are also provided.

Systoles in discrete dynamical systems
NASA Astrophysics Data System (ADS)
Fernandes, Sara; Grácio, Clara; Ramos, Carlos Correia
20130101
The fruitful relationship between Geometry and Graph Theory has been explored by several authors benefiting also the Theory of discrete dynamical systems seen as Markov chains in graphs. In this work we will further explore the relation between these areas, giving a geometrical interpretation of notions from dynamical systems. In particular, we relate the topological entropy with the systole, here defined in the context of discrete dynamical systems. We show that for continuous interval maps the systole is trivial; however, for the class of interval maps with one discontinuity point the systole acquires relevance from the point of view of the dynamical behavior. Moreover, we define the geodesic length spectrum associated to a Markov interval map and we compute the referred spectrum in several examples.

Dark Energy from Discrete Spacetime
PubMed Central
Trout, Aaron D.
20130101
Dark energy accounts for most of the matterenergy content of our universe, yet current theories of its origin rely on radical physical assumptions such as the holographic principle or controversial anthropic arguments. We give a better motivated explanation for dark energy, claiming that it arises from a small negative scalarcurvature present even in empty spacetime. The vacuum has this curvature because spacetime is fundamentally discrete and there are more ways for a discrete geometry to have negative curvature than positive. We explicitly compute this effect using a variant of the well known dynamicaltriangulations (DT) model for quantum gravity. Our model predicts a timevarying nonzero cosmological constant with a current value, in natural units, in agreement with observation. This calculation is made possible by a novel characterization of the possible DT action values combined with numerical evidence concerning their degeneracies. PMID:24312502

A FORTRAN Program for Discrete Discriminant Analysis
ERIC Educational Resources Information Center
Boone, James O.; Brewer, James K.
19760101
A Fortran program is presented for discriminant analysis of discrete variables. The program assumes discrete, nominal data with no distributional, variancecovariance assumptions. The program handles a maximum of fifty predictor variables and twelve outcome groups. (Author/JKS)

Efficient genetic algorithms using discretization scheduling.
PubMed
McLay, Laura A; Goldberg, David E
20050101
In many applications of genetic algorithms, there is a tradeoff between speed and accuracy in fitness evaluations when evaluations use numerical methods with varying discretization. In these types of applications, the cost and accuracy vary from discretization errors when implicit or explicit quadrature is used to estimate the function evaluations. This paper examines discretization scheduling, or how to vary the discretization within the genetic algorithm in order to use the least amount of computation time for a solution of a desired quality. The effectiveness of discretization scheduling can be determined by comparing its computation time to the computation time of a GA using a constant discretization. There are three ingredients for the discretization scheduling: population sizing, estimated time for each function evaluation and predicted convergence time analysis. Idealized one and twodimensional experiments and an inverse groundwater application illustrate the computational savings to be achieved from using discretization scheduling. PMID:16156928

Anomalies and Discrete Chiral Symmetries
SciTech Connect
Creutz, M.
20090907
The quantum anomaly that breaks the U(1) axial symmetry of massless multiflavored QCD leaves behind a discrete flavorsinglet chiral invariance. With massive quarks, this residual symmetry has a close connection with the strong CPviolating parameter theta. One result is that if the lightest quarks are degenerate, then a first order transition will occur when theta passes through pi. The resulting framework helps clarify when the rooting prescription for extrapolating in the number of flavors is valid.

Discrete vortex representation of magnetohydrodynamics
SciTech Connect
Kinney, R.; Tajima, T.; Petviashvili, N.; McWilliams, J.C.
19930201
We present an alternative approach to statistical analysis of an intermittent ideal MHD fluid in two dimensions, based on the hydrodynamical discrete vortex model applied to the Elsasser variables. The model contains negative temperature states which predict the formation of magnetic islands, but also includes a natural limit under which the equilibrium states revert to the familiar twinvortex states predicted by hydrodynamical turbulence theories. Numerical dynamical calculations yield equilibrium spectra in agreement with the theoretical predictions.

Discretecontact nanowire photovoltaics
NASA Astrophysics Data System (ADS)
Chitambar, Michelle J.; Wen, Wen; Maldonado, Stephen
20131101
A series of finiteelement simulations have been performed to assess the operational characteristics of a new semiconductor nanowire solar cell design operating under highlevel injection conditions. Specifically, the steadystate currentvoltage behavior of a cylindrical silicon (Si) nanowire with a series of discrete, ohmicselective contacts under intense sunlight illumination was investigated. The scope of the analysis was limited to only the factors that impact the net internal quantum yield for solar to electricity conversion. No evaluations were performed with regards to optical light trapping in the modeled structures. Several aspects in a discretecontact nanowire device that could impact operation were explored, including the size and density of ohmicselective contacts, the size of the nanowire, the electronic quality and conductivity of the nanowire, the surface defect density of the nanowire, and the type of ohmic selectivity employed at each contact. The analysis showed that there were ranges of values for each parameter that supported good to excellent photoresponses, with certain combinations of experimentally attainable material properties yielding internal energy conversion efficiencies at the thermodynamic limit for a single junction cell. The merits of the discretecontact nanowire cell were contrasted with "conventional" nanowire photovoltaic cells featuring a uniform conformal contact and also with planar pointcontact solar cells. The unique capacity of the discretecontact nanowire solar cell design to operate at useful energy conversion efficiencies with low quality semiconductor nanowires (i.e., possessing short chargecarrier lifetimes) with only light doping is discussed. This work thus defines the impetus for future experimental work aimed at developing this photovoltaic architecture.

Symmetric Discrete Orthonormal Stockwell Transform
NASA Astrophysics Data System (ADS)
Wang, Yanwei; Orchard, Jeff
20080901
The Stockwell Transform (ST) is a timefrequency signal decomposition that is gaining in popularity, likely because of its direct relation with the Fourier Transform (FT). A discrete and nonredundant version of the ST, denoted the Discrete Orthonormal Stockwell Transform (DOST), has made the use of the ST more feasible. However, the matrix multiplication required by the DOST can still be a formidable computation, especially for highdimensional data. Moreover, the symmetric property of the ST and FT is not present in the DOST. In this paper, we investigate a new Symmetric Discrete Orthonormal Stockwell Transform (SDOST) that still keeps the nonredundant multiresolution features of the DOST, while maintaining a symmetry property similar to that of the FT. First, we give a brief introduction for the ST and the DOST. Then we analyze the DOST coefficients and modify the transform to get a symmetric version. A small experiment shows that the SDOST has kept the abilities of the DOST and demonstrates the advantage of symmetry when applying the SDOST.

Interference in discrete Wigner functions
SciTech Connect
Cormick, Cecilia; Paz, Juan Pablo
20061215
We analyze some features of the class of discrete Wigner functions that was recently introduced by Gibbons et al. [Phys. Rev. A 70, 062101 (2004)] to represent quantum states of systems with powerofprime dimensional Hilbert spaces. We consider ''cat'' states obtained as coherent superpositions of states with positive Wigner function; for such states we show that the oscillations of the discrete Wigner function typically spread over the entire discrete phase space (including the regions where the two interfering states are localized). This is a generic property, which is in sharp contrast with the usual attributes of Wigner functions that make them useful candidates to display the existence of quantum coherence through oscillations. However, it is possible to find subsets of cat states with a natural phasespace representation, in which the oscillatory regions remain localized. We show that this can be done for interesting families of stabilizer states used in quantum errorcorrecting codes, and illustrate this by analyzing the phasespace representation of the fivequbit errorcorrecting code.

ACS Algorithm in Discrete Ordinates for Pressure Vessel Dosimetry
NASA Astrophysics Data System (ADS)
Walters, William; Haghighat, Alireza
20160201
The Adaptive Collision Source (ACS) method can solve the Linear Boltzmann Equation (LBE) more efficiently by adaptation of the angular quadrature order. This is similar to, and essentially an extension of, the first collision source method. Previously, the ACS methodology has been implemented into the TITAN discrete ordinates code, and has shown speedups of 24 on a simple test problem, with very little loss of accuracy (within a provided adaptive tolerance). This work examines the use of the ACS method for a more realistic problem: pressure vessel dosimetry with the VENUS2 MOXfuelled reactor dosimetry benchmark. The ACS method proved to be able to obtain accurate results while being approximately twice as efficient as using a constant quadrature in a standard source iteration scheme.

Optical pattern recognition for missile guidance
NASA Astrophysics Data System (ADS)
Casasent, D.
19821101
Progress on realtime spatial light modulators, image pattern recognition and optical signal processing for missile guidance is documented. A full description of our test and evaluation of the Soviet PRIZ spatial light modulator is included. In image pattern recognition, a unified formulation of four different and new types of synthetic discriminant functions is advanced. These include synthetic discriminant functions for intra and interclass pattern recognition and multiclass pattern recognition. In the area of image pattern recognition, we also advance new statistical synthetic discriminant function filter concepts and a new principal component synthetic discriminant function. These analyses utilize new performance measures and new image models. Conventional holographic pattern recognition research conducted under AFOSR support is also reviewed. Our new AFOSR optical signal processing research concerns optical matrixvector processors. Initial research in this area includes fabrication of a fiberoptic microprocessorbased iterative optical processor and its use in adaptive phased array radar processing and for the calculation of eigenvalues and eigenvectors of a matrix.

Observability of discretized partial differential equations
NASA Technical Reports Server (NTRS)
Cohn, Stephen E.; Dee, Dick P.
19880101
It is shown that complete observability of the discrete model used to assimilate data from a linear partial differential equation (PDE) system is necessary and sufficient for asymptotic stability of the data assimilation process. The observability theory for discrete systems is reviewed and applied to obtain simple observability tests for discretized constantcoefficient PDEs. Examples are used to show how numerical dispersion can result in discrete dynamics with multiple eigenvalues, thereby detracting from observability.

SEA screening of voluntary climate change plans: A story of noncompliant discretion
SciTech Connect
Kørnøv, Lone Wejs, Anja
20130715
Screening within Strategic Environmental Assessment (SEA) is the first critical stage involving considerations on whether an assessment is carried out or not. Although legislation and guidance offer practitioners a legal and logical approach to the screening process, it is inevitable that discretionary judgement takes place and will impact on the screening decision. This article examines the results of discretion involved in screening of climate change plans (CCPs) in a Danish context. These years voluntary CCPs are developed as a response to the global and local emergence of both mitigation and adaptation, and the voluntary commitment by the local authorities is an indication of an emerging norm of climate change as an important issue. This article takes its point of departure in the observation that SEA is not undertaken for these voluntary CCPs. The critical analysis of this phenomenon rests upon a documentary study of Danish CCPs, interviews with a lawyer and ministerial key person and informal discussions between researchers, practitioners and lawyers on whether climate change plans are covered by SEA legislation and underlying reasons for the present practice. Based on a critical analysis of mandatory SEA and/or obligation to screen CCPs according to significance criteria, the authors find that 18 out of the 48 CCPs are mandatory to SEA and 9 would require a screening of significance and thereby potentially be followed by a SEA. In practice only one plan was screened and one was environmentally assessed. The legal, democratic and environmental consequences of this SEA practice are critically discussed. Hereunder is the missed opportunity to use the broad environmental scope of SEA to avoid a narrow focus on energy and CO{sub 2} in CCPs, and the question whether this practice in Denmark complies with the EU Directive.  Highlights: ► It is inevitable that discretionary judgement takes place and will impact on the screening decision. ► The article hereby

Micro guidance and control synthesis: New components, architectures, and capabilities
NASA Technical Reports Server (NTRS)
Mettler, Edward; Hadaegh, Fred Y.
19930101
New GN&C (guidance, navigation and control) system capabilities are shown to arise from component innovations that involve the synergistic use of microminiature sensors and actuators, microelectronics, and fiber optics. MicroGN&C system and component concepts are defined that include microactuated adaptive optics, micromachined inertial sensors, fiberoptic data nets and lightpower transmission, and VLSI microcomputers. The thesis is advanced that these microminiaturization products are capable of having a revolutionary impact on space missions and systems, and that GN&C is the pathfinder microtechnology application that can bring that about.

Adaptive Algebraic Multigrid Methods
SciTech Connect
Brezina, M; Falgout, R; MacLachlan, S; Manteuffel, T; McCormick, S; Ruge, J
20040409
Our ability to simulate physical processes numerically is constrained by our ability to solve the resulting linear systems, prompting substantial research into the development of multiscale iterative methods capable of solving these linear systems with an optimal amount of effort. Overcoming the limitations of geometric multigrid methods to simple geometries and differential equations, algebraic multigrid methods construct the multigrid hierarchy based only on the given matrix. While this allows for efficient blackbox solution of the linear systems associated with discretizations of many elliptic differential equations, it also results in a lack of robustness due to assumptions made on the nearnull spaces of these matrices. This paper introduces an extension to algebraic multigrid methods that removes the need to make such assumptions by utilizing an adaptive process. The principles which guide the adaptivity are highlighted, as well as their application to algebraic multigrid solution of certain symmetric positivedefinite linear systems.

Reliability and Validity of the Vietnamese Vineland Adaptive Behavior Scales with PreschoolAge Children
ERIC Educational Resources Information Center
Goldberg, Michael R.; Dill, Charles A.; Shin, Jin Y.; Nhan, Nguyen Viet
20090101
This study was conducted to examine an adaptation of the Vineland Adaptive Behavior Scale (VABS) [Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (1984). "The Vineland Adaptive Behavior Scales." Circle Pines, MN: America Guidance Service; Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (2005). "Vineland Adaptive Behavior Scales Second Edition…

In visual search, guidance by surface type is different than classic guidance
PubMed Central
Wolfe, Jeremy M; Reijnen, Ester; Van Wert, Michael J.; Kuzmova, Yoana
20090101
Visual search for targets among distractors is more efficient if attention can be guided to targets by attributes like color. In realworld search, we guide attention using information about surfaces. (e.g., paintings are on walls). We compare “classic” color guidance to surface guidance in “scenes” of cubes. When a target can lie on one of many surfaces, color guidance is effective but surface guidance is not (Exp. 13). Surface guidance works when cued surfaces are coplanar (Exp. 4) or few in number (Exp. 5). We speculate that surface guidance is slow and limited to very few surfaces at one time. PMID:19236891

Flight Guidance System Requirements Specification
NASA Technical Reports Server (NTRS)
Miller, Steven P.; Tribble, Alan C.; Carlson, Timothy M.; Danielson, Eric J.
20030101
This report describes a requirements specification written in the RSMLe language for the mode logic of a Flight Guidance System of a typical regional jet aircraft. This model was created as one of the first steps in a fiveyear project sponsored by the NASA Langley Research Center, Rockwell Collins Inc., and the Critical Systems Research Group of the University of Minnesota to develop new methods and tools to improve the safety of avionics designs. This model will be used to demonstrate the application of a variety of methods and techniques, including safety analysis of system and subsystem requirements, verification of key properties using theorem provers and model checkers, identification of potential sources mode confusion in system designs, partitioning of applications based on the criticality of system hazards, and autogeneration of avionics quality code. While this model is representative of the mode logic of a typical regional jet aircraft, it does not describe an actual or planned product. Several aspects of a full Flight Guidance System, such as recovery from failed sensors, have been omitted, and no claims are made regarding the accuracy or completeness of this specification.

Family planning methods: new guidance.
PubMed
19961001
Presented in this report are the recommendations of two expert groups, the Technical Guidance/Competence Working Group of the US Agency for International Development's Maximizing Access and Quality Initiative and the World Health Organization's Family Planning and Population Unit, regarding currently available family planning methods. The former group addressed key biomedical questions and formulated recommendations about 11 groups of family planning methods: combined oral contraceptives, progestinonly pills during breast feeding, progestinonly injectables, combined injectable contraceptives, Norplant implants, copperbearing IUDs, tubal occlusion, vasectomy, lactational amenorrhea method, natural family planning, and barrier methods. A table presents the relative importance, by method, of procedures such as pelvic exam, blood pressure reading, breast exam, and screening for sexually transmitted diseases and cervical cancer. The medical eligibility recommendations for each method are also presented in tabular form, with four categories for temporary methods: 1) no restrictions on use, 2) advantages generally outweigh theoretical or proven risks, 3) theoretical or proven risks usually outweigh the advantages, and 4) unacceptable health risks. Included among the 41 conditions for which eligibility criteria are specified are age, smoking, thromboembolic disorder, headaches, irregular vaginal bleeding, family history of breast cancer, obesity, drug interactions, parity, breast feeding, postpartum, and postabortion. The new guidance presented in this report enables providers to give family planning clients expanded contraceptive choices while ensuring method safety and effectiveness. PMID:9342775

ChanceConstrained Guidance With NonConvex Constraints
NASA Technical Reports Server (NTRS)
Ono, Masahiro
20110101
Missions to small bodies, such as comets or asteroids, require autonomous guidance for descent to these small bodies. Such guidance is made challenging by uncertainty in the position and velocity of the spacecraft, as well as the uncertainty in the gravitational field around the small body. In addition, the requirement to avoid collision with the asteroid represents a nonconvex constraint that means finding the optimal guidance trajectory, in general, is intractable. In this innovation, a new approach is proposed for chanceconstrained optimal guidance with nonconvex constraints. Chanceconstrained guidance takes into account uncertainty so that the probability of collision is below a specified threshold. In this approach, a new bounding method has been developed to obtain a set of decomposed chance constraints that is a sufficient condition of the original chance constraint. The decomposition of the chance constraint enables its efficient evaluation, as well as the application of the branch and bound method. Branch and bound enables nonconvex problems to be solved efficiently to global optimality. Considering the problem of finitehorizon robust optimal control of dynamic systems under Gaussiandistributed stochastic uncertainty, with state and control constraints, a discretetime, continuousstate linear dynamics model is assumed. Gaussiandistributed stochastic uncertainty is a more natural model for exogenous disturbances such as wind gusts and turbulence than the previously studied setbounded models. However, with stochastic uncertainty, it is often impossible to guarantee that state constraints are satisfied, because there is typically a nonzero probability of having a disturbance that is large enough to push the state out of the feasible region. An effective framework to address robustness with stochastic uncertainty is optimization with chance constraints. These require that the probability of violating the state constraints (i.e., the probability of

Autonomous and cooperative multiUAV guidance in adversarial environment
NASA Astrophysics Data System (ADS)
Zengin, Ugur
The research presented in this dissertation is aimed at developing rulebased autonomous and cooperative guidance strategies for UAVs to perform missions such as path planning, target tracking and rendezvous while reducing their risk/threat exposure level, and avoiding threats and/or obstacles by utilizing measurement information provided by sensors. First, a mathematical formulation is developed to represent the area of operation that contains various types of threats, obstacles, and restricted areas, in a single framework. Once constructed, there will be no need to distinguish between threats, obstacles and restricted areas as the framework already contains the information on what needs to be avoided and the level of penalty for a given position in the area. This framework provides the mathematical foundation for the guidance strategies to make intelligent decisions during the execution of the mission and also provides scalar metrics to assess the performance of a guidance strategy in a given mission. The autonomous guidance strategies are developed by using a rulebased expert system approach with the requirements of completing assigned mission or task, avoiding obstacle/restrictedareas, minimizing threat exposure level, considering the dynamic and communication constraints of the UAVs and avoiding collision. All these requirements and objectives are quantified and prioritized to facilitate the development of guidance algorithms that can be executed in realtime. The strategies consist of a set of "decision states", which contain rules to determine how the host UAV should move by generating heading and speed signals. Cooperation of multiple UAVs is modeled by minimizing a cost function, which is constructed based on the level of threat exposure for each UAV and distance of each UAV relative to the target. This improves the performance of the system in the terms of increasing the total area of coverage of the sensors onboard the UAVs, increasing the flexibility

Nonconforming mortar element methods: Application to spectral discretizations
NASA Technical Reports Server (NTRS)
Maday, Yvon; Mavriplis, Cathy; Patera, Anthony
19880101
Spectral element methods are ptype weighted residual techniques for partial differential equations that combine the generality of finite element methods with the accuracy of spectral methods. Presented here is a new nonconforming discretization which greatly improves the flexibility of the spectral element approach as regards automatic mesh generation and nonpropagating local mesh refinement. The method is based on the introduction of an auxiliary mortar trace space, and constitutes a new approach to discretizationdriven domain decomposition characterized by a clean decoupling of the local, structurepreserving residual evaluations and the transmission of boundary and continuity conditions. The flexibility of the mortar method is illustrated by several nonconforming adaptive NavierStokes calculations in complex geometry.

Energy angular momentum closedloop guidance
NASA Astrophysics Data System (ADS)
Patera, Russell P.
20150301
A novel guidance algorithm for launch vehicle ascent to the desired mission orbit is proposed. The algorithm uses total specific energy and orbital angular momentum as new state vector parameters. These parameters are ideally suited for the ascent guidance task, since the guidance algorithm steers the launch vehicle along a preflight optimal trajectory in energy angular momentum space. The guidance algorithm targets apogee, perigee, inclination and right ascension of ascending node. Computational complexities are avoided by eliminating time in the guidance computation and replacing it with angular momentum magnitude. As a result, vehicle acceleration, mass, thrust, length of motor burns, and staging times are also eliminated from the pitch plane guidance calculations. The algorithm does not involve launch vehicle or target state propagation, which results in minimal computational effort. Proof of concept of the new algorithm is presented using several numerical examples that illustrate performance results.

Guidance assistance, autonomous guidance and assisted distance guidance in precision agriculture
NASA Astrophysics Data System (ADS)
Gomez Gil, Jaime
The present doctoral thesis analyses the potential of technological advances in electronics, telematics and communications for their application in agriculture. Research has been carried out and some prototypes have been developed in four stages: In a first phase, it has been carried out the analysis and development of guidance assistance devices. It has been carried out the development of a microcontroller based device which has been patented by the author of this thesis and later, has been developed and commercialized by the company GMV Sistemas. In a second phase, it has been developed a module of distance guidance which allows the remote driving of an agricultural tractor. There have been made the mechanical modifications in a tractor and the necessary hardware has been installed in order to allow the remote control of the tractor steering. The laptop receives the guidance instructions by means of wireless communication from the computer installed in the base. In a third phase, there have been developed two autonomous guidance systems, one by means of GPS and the other by means of Computer Vision, using as base the platform developed in the previous phase. It is incorporated a module of path generation from the plot outline. With this trajectory, the tractor is able to do most of the farming work in a plot without the participation of the driver. The last phase has been developed at the same time than the previous ones and it is located in Precision Agriculture. In this phase it has been carried out the performance of a centrifugal spreader of fertilizer and it has been developed an application for the generation in a precise way of fertilizer maps. The carried out studies have produced real developments implanted on the machinery of the author's farm. The development of the work has been carried out on a software platform with modules which are intercommunicated between them, because a large part of the developed applications have a common base of work. This

The Utilization of a Computer Assisted Guidance System in Academic Advising
ERIC Educational Resources Information Center
Pfautz, Charles Van Vleck
20100101
Computer assisted guidance systems may adapt well to various models of academic advising, and they have the ability to address the challenge of meeting the diverse advising needs of community college students without sacrificing the integrity of academic advising (Fowkes & McWhirter, 2007). The purpose of this qualitative case study was to assess…

The Social Influence of Two ComputerAssisted Career Guidance Systems: DISCOVER and SIGI.
ERIC Educational Resources Information Center
Sampson, James P., Jr.; And Others
19920101
Compared perceptions of expertness, attractiveness, and trustworthiness of computerassisted guidance systems, as measured by adapted version of Counselor Rating Form, for 107 college students in two treatment conditions (DISCOVER and SIGI) and computer imaging control condition. Findings showed that students in both treatment conditions had more…

Virtual Ultrasound Guidance for Inexperienced Operators
NASA Technical Reports Server (NTRS)
Caine, Timothy; Martin, Davis
20120101
Medical ultrasound or echocardiographic studies are highly operatordependent and generally require lengthy training and internship to perfect. To obtain quality echocardiographic images in remote environments, such as onorbit, remote guidance of studies has been employed. This technique involves minimal training for the user, coupled with remote guidance from an expert. When realtime communication or expert guidance is not available, a more autonomous system of guiding an inexperienced operator through an ultrasound study is needed. One example would be missions beyond low Earth orbit, in which the time delay inherent with communication will make remote guidance impractical.

Driven discrete time quantum walks
NASA Astrophysics Data System (ADS)
Hamilton, Craig S.; Barkhofen, Sonja; Sansoni, Linda; Jex, Igor; Silberhorn, Christine
20160701
We introduce the driven discrete time quantum walk (QW), where walkers are added during the walk instead of only at the beginning. This leads to interference in walker number and very different dynamics when compared to the original QW. These dynamics have two regimes, which we illustrate using the onedimensional line. Then, we explore a search application which has certain advantages over current search protocols, namely that it does not require a complicated initial state nor a specific measurement time to observe the marked state. Finally, we describe a potential experimental implementation using existing technology.

A semianalytical guidance algorithm for autonomous landing
NASA Astrophysics Data System (ADS)
Lunghi, Paolo; Lavagna, Michèle; Armellin, Roberto
20150601
One of the main challenges posed by the next space systems generation is the high level of autonomy they will require. Hazard Detection and Avoidance is a key technology in this context. An adaptive guidance algorithm for landing that updates the trajectory to the surface by means of an optimal control problem solving is here presented. A semianalytical approach is proposed. The trajectory is expressed in a polynomial form of minimum order to satisfy a set of boundary constraints derived from initial and final states and attitude requirements. By imposing boundary conditions, a fully determined guidance profile is obtained, function of a restricted set of parameters. The guidance computation is reduced to the determination of these parameters in order to satisfy path constraints and other additional constraints not implicitly satisfied by the polynomial formulation. The algorithm is applied to two different scenarios, a lunar landing and an asteroidal landing, to highlight its general validity. An extensive Monte Carlo test campaign is conducted to verify the versatility of the algorithm in realistic cases, by the introduction of attitude control systems, thrust modulation, and navigation errors. The proposed approach proved to be flexible and accurate, granting a precision of a few meters at touchdown.

LongTerm Stewardship Baseline Report and Transition Guidance
SciTech Connect
Kristofferson, Keith
20011101
Longterm stewardship consists of those actions necessary to maintain and demonstrate continued protection of human health and the environment after facility cleanup is complete. As the Department of Energy’s (DOE) lead laboratory for environmental management programs, the Idaho National Engineering and Environmental Laboratory (INEEL) administers DOE’s longterm stewardship science and technology efforts. The INEEL provides DOE with technical, and scientific expertise needed to oversee its longterm environmental management obligations complexwide. Longterm stewardship is administered and overseen by the Environmental Management Office of Science and Technology. The INEEL LongTerm Stewardship Program is currently developing the management structures and plans to complete INEELspecific, longterm stewardship obligations. This guidance document (1) assists in ensuring that the program leads transition planning for the INEEL with respect to facility and site areas and (2) describes the classes and types of criteria and data required to initiate transition for areas and sites where the facility mission has ended and cleanup is complete. Additionally, this document summarizes current information on INEEL facilities, structures, and release sites likely to enter longterm stewardship at the completion of DOE’s cleanup mission. This document is not intended to function as a discrete checklist or local procedure to determine readiness to transition. It is an overarching document meant as guidance in implementing specific transition procedures. Several documents formed the foundation upon which this guidance was developed. Principal among these documents was the LongTerm Stewardship Draft Technical Baseline; A Report to Congress on LongTerm Stewardship, Volumes I and II; Infrastructure LongRange Plan; Comprehensive Facility Land Use Plan; INEEL EndState Plan; and INEEL Institutional Plan.

fMRI adaptation revisited.
PubMed
Larsson, Jonas; Solomon, Samuel G; Kohn, Adam
20160701
Adaptation has been widely used in functional magnetic imaging (fMRI) studies to infer neuronal response properties in human cortex. fMRI adaptation has been criticized because of the complex relationship between fMRI adaptation effects and the multiple neuronal effects that could underlie them. Many of the longstanding concerns about fMRI adaptation have received empirical support from neurophysiological studies over the last decade. We review these studies here, and also consider neuroimaging studies that have investigated how fMRI adaptation effects are influenced by highlevel perceptual processes. The results of these studies further emphasize the need to interpret fMRI adaptation results with caution, but they also provide helpful guidance for more accurate interpretation and better experimental design. In addition, we argue that rather than being used as a proxy for measurements of neuronal stimulus selectivity, fMRI adaptation may be most useful for studying populationlevel adaptation effects across cortical processing hierarchies. PMID:26703375

78 FR 48175  Retrospective Review of Draft Guidance Documents Issued Before 2010; Withdrawal of Guidances
Federal Register 2010, 2011, 2012, 2013, 2014
20130807
... ``Administrative Practices and Procedures; Good Guidance Practices'' (GGP) (65 FR 56468; September 19, 2000). The... manufacturing practice (cGMP) compliance specific to manufacturing, processing, and dose unit sampling and... following guidances: 1. ``Manufacturing, Processing, or Holding Active Pharmaceutical...

Adaptive Management
EPA Science Inventory
Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive managem...

Acquiring case adaptation knowledge: A hybrid approach
SciTech Connect
Leake, D.B.; Kinley, A.; Wilson, D.
19961231
The ability of casebased reasoning (CBR) systems to apply cases to novel situations depends on their case adaptation knowledge. However, endowing CBR systems with adequate adaptation knowledge has proven to be a very difficult task. This paper describes a hybrid method for performing case adaptation, using a combination of rulebased and casebased reasoning. It shows how this approach provides a framework for acquiring flexible adaptation knowledge from experiences with autonomous adaptation and suggests its potential as a basis for acquisition of adaptation knowledge from interactive user guidance. It also presents initial experimental results examining the benefits of the approach and comparing the relative contributions of case learning and adaptation learning to reasoning performance.

Can coffee improve image guidance?
NASA Astrophysics Data System (ADS)
Wirz, Raul; Lathrop, Ray A.; Godage, Isuru S.; BurgnerKahrs, Jessica; Russell, Paul T.; Webster, Robert J.
20150301
Anecdotally, surgeons sometimes observe large errors when using image guidance in endonasal surgery. We hypothesize that one contributing factor is the possibility that operating room personnel might accidentally bump the optically tracked rigid body attached to the patient after registration has been performed. In this paper we explore the registration error at the skull base that can be induced by simulated bumping of the rigid body, and find that large errors can occur when simulated bumps are applied to the rigid body. To address this, we propose a new fixation method for the rigid body based on granular jamming (i.e. using particles like ground coffee). Our results show that our granular jamming fixation prototype reduces registration error by 28%68% (depending on bump direction) in comparison to a standard Brainlab reference headband.

Endangerment assessment guidance. Final report
SciTech Connect
Not Available
19851021
The directive clarifies the requirement that an endangerment assessment be developed to support all administrative and judicial enforcement actions under Section 106 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Section 7003 of the Resource Conservation and Recovery Act (RCRA). Before taking enforcement action under these provisions to abate the hazards or potential hazards at a site, the Environmental Protection Agency (EPA) must be able to properly document and justify its assertion that an imminent and substantial endangerment to public health or welfare or the environment may exist. The endangerment assessment provides the documentation and justification. The endangerment assessment is not necessary to support Section 104 actions. It also provides guidance on the content, timing, level of detail, format, and resources required for the preparation of endangerment assessments.

Longwall Guidance and Control Development
NASA Technical Reports Server (NTRS)
19820101
The longwall guidance and control (G&C) system was evaluated to determine which systems and subsystems lent themselves to automatic control in the mining of coal. The upper coal/shale interface was identified as the reference for a vertical G&C system, with two sensors (the natural backgound and the sensitized pick) being used to locate and track this boundary. In order to insure a relatively smooth recession surface (roof and floor of the excavated seam), a last and present cut measuring instrument (acoustic sensor) was used. Potentiometers were used to measure elevations of the shearer arms. The intergration of these components comprised the vertical control system (pitch control). Yaw and roll control were incorporated into a face alignment system which was designed to keep the coal face normal to its external boundaries. Numerous tests, in the laboratory and in the field, have confirmed the feasibility of automatic horizon control, as well as determining the face alignment.

Orion Cislunar Guidance and Navigation
NASA Technical Reports Server (NTRS)
D'Souza, Christopher; Crain, Timothy; Clark, Fred C.
20070101
The Orion vehicle is being designed to provide nominal crew transport to the lunar transportation stack in low Earth orbit, crew abort prior during transit to the moon, and crew return to Earth once lunar orbit is achieved. Design of guidance and navigation algorithms to perform maneuvers in support of these functions is dependent on the support provided by navigation infrastructure, the performance of the onboard GN&C system, and the choice of trajectory maneuver methodology for outbound and return mission phases. This paper documents the preliminary integrated analyses performed by members of the Orion Orbit GN&C System team investigating the navigation update accuracy of a modern equivalent to the Apollo era ground tracking network and the expected onboard dispersion and navigation errors during a lunar mission using a linear covariance error analysis technique.

Guidance, Navigation, and Control Program
NASA Technical Reports Server (NTRS)
Hinkel, Heather; Tamblyn, Scott; Jackson, William L.; Foster, Chris; Brazzel, Jack; Manning, Thomas R.; Clark, Fred; Spehar, Pete; Barrett, Jim D.; Milenkovic, Zoran
20110101
The Rendezvous and Proximity Operations Program (RPOP) is realtime guidance, navigation, and control (GN&C) domain pilotingaid software that provides 3D Orbiter graphics and runs on the Space Shuttle's Criticality3 Payload and General Support Computer (PGSC) in the crew cockpit. This software provides the crew with Situational Awareness during the rendezvous and proximity operations phases of flight. RPOP can be configured from flight to flight, accounting for missionspecific flight scenarios and target vehicles, via initialization load (Iload) data files. The software provides realtime, automated, closedloop guidance recommendations and the capability to integrate the crew s manual backup techniques. The software can bring all relative navigation sensor data, including the Orbiter's GPC (general purpose computer) data, into one central application to provide comprehensive situational awareness of the rendezvous and proximity operations trajectory. RPOP also can separately maintain trajectory estimates (past, current, and predicted) based on certain data types and coplot them, in order to show how the various navigation solutions compare. RPOP s best estimate of the relative trajectory is determined by a relative Kalman filter processing data provided by the sensor suite s most accurate sensor, the trajectory control sensor (TCS). Integrated with the Kalman filter is an algorithm that identifies the reflector that the TCS is tracking. Because RPOP runs on PC laptop computers, the development and certification lifecycles are more agile, flexible, and cheaper than those that govern the Orbiter FSW (flight software) that runs in the GPC. New releases of RPOP can be turned around on a 3 to 6month template, from new Change Request (CR) to certification, depending on the complexity of the changes.

Discreteness effects in population dynamics
NASA Astrophysics Data System (ADS)
Guevara Hidalgo, Esteban; Lecomte, Vivien
20160501
We analyse numerically the effects of small population size in the initial transient regime of a simple example population dynamics. These effects play an important role for the numerical determination of large deviation functions of additive observables for stochastic processes. A method commonly used in order to determine such functions is the socalled cloning algorithm which in its nonconstant population version essentially reduces to the determination of the growth rate of a population, averaged over many realizations of the dynamics. However, the averaging of populations is highly dependent not only on the number of realizations of the population dynamics, and on the initial population size but also on the cutoff time (or population) considered to stop their numerical evolution. This may result in an overinfluence of discreteness effects at initial times, caused by small population size. We overcome these effects by introducing a (realizationdependent) time delay in the evolution of populations, additional to the discarding of the initial transient regime of the population growth where these discreteness effects are strong. We show that the improvement in the estimation of the large deviation function comes precisely from these two main contributions.

Climate adaptation planning in practice: an evaluation of adaptation plans from three developed nations
SciTech Connect
Preston, Benjamin L; Westaway, Richard M.; Yuen, Emma J.
20110401
Formal planning for climate change adaptation is emerging rapidly at a range of geopolitical scales. This first generation of adaptation plans provides useful information regarding how institutions are framing the issue of adaptation and the range of processes that are recognized as being part of an adaptation response. To better understand adaptation planning among developed nations, a set of 57 adaptation plans from Australia, the United Kingdom and the United States was evaluated against a suite of 19 planning processes identified from existing guidance instruments for adaptation planning. Total scores among evaluated plans ranged from 16% of the maximum possible score to 61%, with an average of 37%. These results suggest adaptation plans are largely underdeveloped. Critical weaknesses in adaptation planning are related to limited consideration for nonclimatic factors as well as neglect for issues of adaptive capacity including entitlements to various forms of capital needed for effective adaptation. Such gaps in planning suggest there are opportunities for institutions to make better use of existing guidance for adaptation planning and the need to consider the broader governance context in which adaptation will occur. In addition, the adaptation options prescribed by adaptation plans reflect a preferential bias toward lowrisk capacitybuilding (72% of identified options) over the delivery of specific actions to reduce vulnerability. To the extent these findings are representative of the state of developed nation adaptation planning, there appear to be significant deficiencies in climate change preparedness, even among those nations often assumed to have the greatest adaptive capacity.

A fixedpoint framework for launch vehicle ascent guidance
NASA Astrophysics Data System (ADS)
Zhang, Lijun
comparison to Finite Difference (FD) algorithm, the FixedPoint Iteration algorithm is more adaptive to the "cold start" case for endoatmospheric ascent guidance. The simulations also validate the feasibility of the methodology presented in this research in rapid panning and guidance for ascent through atmosphere.

78 FR 56752  Interim Staff Guidance Specific Environmental Guidance for Integral Pressurized Water Reactors...
Federal Register 2010, 2011, 2012, 2013, 2014
20130913
... COMMISSION Interim Staff Guidance Specific Environmental Guidance for Integral Pressurized Water Reactors... and operate integral pressurized water reactors (iPWR). This guidance applies to environmental reviews... purchase copies of public documents at the NRC's PDR, Room O1F21, One White Flint North, 11555...

On Cryptographic Schemes Based on Discrete Logarithms and Factoring
NASA Astrophysics Data System (ADS)
Joye, Marc
At CRYPTO 2003, Rubin and Silverberg introduced the concept of torusbased cryptography over a finite field. We extend their setting to the ring of integers modulo N. We so obtain compact representations for cryptographic systems that base their security on the discrete logarithm problem and the factoring problem. This results in smaller key sizes and substantial savings in memory and bandwidth. But unlike the case of finite fields, analogous tracebased compression methods cannot be adapted to accommodate our extended setting when the underlying systems require more than a mere exponentiation. As an application, we present an improved, torusbased implementation of the ACJT group signature scheme.

Guidance for performing preliminary assessments under CERCLA
SciTech Connect
19910901
EPA headquarters and a national site assessment workgroup produced this guidance for Regional, State, and contractor staff who manage or perform preliminary assessments (PAs). EPA has focused this guidance on the types of sites and site conditions most commonly encountered. The PA approach described in this guidance is generally applicable to a wide variety of sites. However, because of the variability among sites, the amount of information available, and the level of investigative effort required, it is not possible to provide guidance that is equally applicable to all sites. PA investigators should recognize this and be aware that variation from this guidance may be necessary for some sites, particularly for PAs performed at Federal facilities, PAs conducted under EPA`s Environmental Priorities Initiative (EPI), and PAs at sites that have previously been extensively investigated by EPA or others. The purpose of this guidance is to provide instructions for conducting a PA and reporting results. This guidance discusses the information required to evaluate a site and how to obtain it, how to score a site, and reporting requirements. This document also provides guidelines and instruction on PA evaluation, scoring, and the use of standard PA scoresheets. The overall goal of this guidance is to assist PA investigators in conducting highquality assessments that result in correct site screening or further action recommendations on a nationally consistent basis.

Vocational Guidance Requests within the International Scene
ERIC Educational Resources Information Center
Goodman, Jane; Gillis, Sarah
20090101
This article summarizes the work of a diverse group of researchers and practitioners from 5 continents on "Vocational Guidance Requests Within the International Scene" presented in the discussion group at a symposium of the International Association for Educational and Vocational Guidance, the Society for Vocational Psychology, and the National…

Behavioral mechanisms of mammalian sperm guidance
PubMed Central
PérezCerezales, Serafín; Boryshpolets, Sergii; Eisenbach, Michael
20150101
In mammals, sperm guidance in the oviduct appears essential for successful sperm arrival at the oocyte. Hitherto, three different potential sperm guidance mechanisms have been recognized: thermotaxis, rheotaxis, and chemotaxis, each of them using specific stimuli – a temperature gradient, fluid flow, and a chemoattractant gradient, respectively. Here, we review sperm behavioral in these mechanisms and indicate commonalities and differences between them. PMID:25999361

HANDBOOK: HAZARDOUS WASTE INCINERATION MEASUREMENT GUIDANCE
EPA Science Inventory
This publication, Volume III of the Hazardous Waste Incineration Guidance Series, contains general guidance to permit writers in reviewing hazardous waste incineration permit applications and trial burn plans. he handbook is a howto document dealing with how incineration measure...

45 CFR 1235.2  Implementation guidance.
Code of Federal Regulations, 2010 CFR
20101001
... 45 Public Welfare 4 20101001 20101001 false Implementation guidance. 1235.2 Section 1235.2... SERVICE LOCALLY GENERATED CONTRIBUTIONS IN OLDER AMERICAN VOLUNTEER PROGRAMS § 1235.2 Implementation guidance. ACTION's implementation of section 224 of the DVSA is based on fundamental principles...

21 CFR 312.145  Guidance documents.
Code of Federal Regulations, 2013 CFR
20130401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.145 Guidance documents. (a) FDA has... Evaluation and Research (CBER) maintain lists of guidance documents that apply to the centers'...

21 CFR 312.145  Guidance documents.
Code of Federal Regulations, 2012 CFR
20120401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.145 Guidance documents. (a) FDA has... Evaluation and Research (CBER) maintain lists of guidance documents that apply to the centers'...

21 CFR 312.145  Guidance documents.
Code of Federal Regulations, 2014 CFR
20140401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.145 Guidance documents. (a) FDA has... Evaluation and Research (CBER) maintain lists of guidance documents that apply to the centers'...

21 CFR 312.145  Guidance documents.
Code of Federal Regulations, 2011 CFR
20110401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.145 Guidance documents. (a) FDA has... Evaluation and Research (CBER) maintain lists of guidance documents that apply to the centers'...

Educational Guidance for Adults. Identifying Competences.
ERIC Educational Resources Information Center
Oakeshott, Martin
A brief study conducted for the Further Education Unit, Great Britain, defined the competencies associated with educational guidance for adults. The objective was to develop a qualification for educational guidance workers with adults. The project provided an example of applying a competence model to a "higher level" interpersonal field of work.…

Learners' Needs in CollegeBased Guidance.
ERIC Educational Resources Information Center
Further Education Unit, London (England).
Recent Further Education Unit (FEU) research has provided clear evidence of technical college students' needs for career and educational guidance throughout their program of study. Inhouse technical college guidance services to individuals and institutions offer a number of benefits to both students receiving the services and the institutions…

Guidance Counsellor Strategies for Handling Bullying
ERIC Educational Resources Information Center
PowerElliott, Michleen; Harris, Gregory E.
20120101
The purpose of this exploratorydescriptive study was to examine how guidance counsellors in the province of Newfoundland and Labrador would handle a specific verbalrelational bullying incident. Also of interest was guidance counsellor involvement and training in bullying programmes and Positive Behaviour Supports. Data for this study was…

78 FR 15710  Strong Sensitizer Guidance
Federal Register 2010, 2011, 2012, 2013, 2014
20130312
...The U.S. Consumer Product Safety Commission (CPSC or Commission) is announcing the availability of a document prepared by CPSC staff titled, ``Strong Sensitizer Guidance.'' This guidance document is intended to clarify the ``strong sensitizer'' definition, assist manufacturers in understanding how CPSC staff would assess whether a substance and/or product containing that substance should be......

Career Guidance in the Elementary School
ERIC Educational Resources Information Center
Smith, Phyllis E.; Rost, Paul
19730101
Three practical ideas that can be implemented in elementary schools are given: (1) a guidance committee (composed of representatives from each grade level and an administrator) to facilitate involvement in the school guidance program; (2) field trips to introduce students to the world of work and to establish motivations for learning subject…

Social Benefits of Career Guidance. NICEC Briefing.
ERIC Educational Resources Information Center
Killeen, John; Watts, Tony; Kidd, Jenny
Social benefits can be thought of as aggregates of individual benefits, though with possible "snowball" effects. Potential social benefits of career guidance fall into the following two main categories: reducing social exclusion and enhancing social development. Guidance is a way of making the structure of society work, by linking individual needs…

Career Guidance in Wales: Retrospect and Prospect
ERIC Educational Resources Information Center
Clark, Mike; Talbot, John
20060101
Deregulation of the LEA Careers Service followed by the establishment of the National Assembly for Wales in 1999 led, through consultation, to the establishment of a bilingual allage career guidance service under the banner of Careers Wales. The article traces the history of career guidance in Wales from 1974, showing how it has taken a very…

Career Guidance and Public Mental Health
ERIC Educational Resources Information Center
Robertson, Peter J.
20130101
Career guidance may have the potential to promote public health by contributing positively to both the prevention of mental health conditions and to population level wellbeing. The policy implications of this possibility have received little attention. Career guidance agencies are well placed to reach key target groups. Producing persuasive…

Foundations for Policy in Guidance and Counseling.
ERIC Educational Resources Information Center
Herr, Edwin L., Ed.; Pinson, Nancy M., Ed.
This book provides educators, counselors, policy makers, and community members with information about the state of the art of federal and state policy in guidance and counseling. The two chapters in part 1, Overview, are: "Foundations for Policy in Guidance and Counseling: An Introduction", by Edwin L. Herr and Nancy M. Pinson; and "A Counselor…

The Internationalization of Educational and Vocational Guidance
ERIC Educational Resources Information Center
Savickas, Mark L.; Van Esbroeck, Raoul; Herr, Edwin L.
20050101
The authors identify and discuss the main themes from the discourse on the internationalization of educational and vocational guidance at the 2004 "Symposium on International Perspectives on Career Development," co sponsored by the International Association for Educational and Vocational Guidance and the National Career Development Association.…

78 FR 57450  State Rail Plan Guidance
Federal Register 2010, 2011, 2012, 2013, 2014
20130918
... authorized in the Act and available under the HighSpeed Intercity Passenger Rail program. This guidance... qualifies States to receive grants for highspeed rail only. Response: Operational information about all... Federal Railroad Administration State Rail Plan Guidance AGENCY: Federal Railroad Administration...

Getting Closer: Workplace Guidance for Lifelong Learning
ERIC Educational Resources Information Center
Plant, Peter; Turner, Bob
20050101
The purposes of this article are twofold. First, it considers the policy links between guidance and lifelong learning, highlighting in particular the implications of findings from a recent study by the Organisation for Economic Cooperation and Development (OECD). Secondly, it critically compares two approaches to workplace guidance about…

New Tools for Guidance in Business Education.
ERIC Educational Resources Information Center
Shimberg, Benjamin
Several recently developed measurement instruments, the General Aptitude Test Battery (GATB), the Comparative Guidance and Placement Program (CGP), the Kuder Occupational Interest Survey (DD), the Ohio Vocational Interest Survey (OVIS), and the Gordon Occupational Check List, are considered in connection with guidance testing for occupational…

Career Guidance in the Elementary School
ERIC Educational Resources Information Center
Leonard, George E.
19710101
The purpose of this column is to discuss, describe and disseminate information regarding career guidance principles and practices in the elementary schools. Specifically the activities of the Developmental Career Guidance Projects in inner city Detroit are described. The activities emphasize action involvement of children while didactic learning…

Elementary School Guidance Work Conference. Conference Report.
ERIC Educational Resources Information Center
Herr, Edwin L.; Hershberger, James K.
In October, 1967, 100 invited participants representing all aspects of guidance, education, school administration, counselor education, psychology, and interested government agencies in Pennsylvania met for three days to listen, think, discuss, and hopefully develop some recommendations for those who want a better program of elementary guidance.…

Preparation of Occupational Guidance Counselors. Final Report.
ERIC Educational Resources Information Center
North Carolina State Dept. of Public Instruction, Raleigh. Occupational Research Unit.
The project had three goals: to increase the supply of elementary counselors in North Carolina, to provide guidance services to seventeen elementary schools in a satisfactory manner so the program would be adopted after expiration of the project, and to provide systematic guidance services for children in grades one through six. Four full time…

Advances in Orion's OnOrbit Guidance and Targeting System Architecture
NASA Technical Reports Server (NTRS)
Scarritt, Sara K.; Fill, Thomas; Robinson, Shane
20150101
NASA's manned spaceflight programs have a rich history of advancing onboard guidance and targeting technology. In order to support future missions, the guidance and targeting architecture for the Orion MultiPurpose Crew Vehicle must be able to operate in complete autonomy, without any support from the ground. Orion's guidance and targeting system must be sufficiently flexible to easily adapt to a wide array of undecided future missions, yet also not cause an undue computational burden on the flight computer. This presents a unique design challenge from the perspective of both algorithm development and system architecture construction. The present work shows how Orion's guidance and targeting system addresses these challenges. On the algorithm side, the system advances the stateoftheart by: (1) steering burns with a simple closedloop guidance strategy based on Shuttle heritage, and (2) planning maneuvers with a cuttingedge twolevel targeting routine. These algorithms are then placed into an architecture designed to leverage the advantages of each and ensure that they function in concert with one another. The resulting system is characterized by modularity and simplicity. As such, it is adaptable to the onorbit phases of any future mission that Orion may attempt.

Approach guidance for outer planet pioneer missions
NASA Technical Reports Server (NTRS)
Bejczy, A. K.
19750101
Onboard optical approach guidance measurements for spinstabilized Pioneertype spacecraft are discussed. Approach guidance measurement accuracy requirements are outlined. The application concept and operation principle of the Vslit star tracker are discussed within the context of approach guidance measurements and measurables. It is shown that the accuracy of onboard optical approach guidance measurements is inherently coupled to the stability characteristics of the spacecraft spin axis. Geometrical and physical measurement parameters are presented for Pioneer entry probe missions to Uranus via Jupiter or Saturn flyby. The impact of these parameters on both sensor instrumentation and measurement system design is discussed. The need for sensing extended objects is shown. The feasibility of implementing an onboard approach guidance measurement system for Pioneertype spacecraft is indicated. Two Pioneer 10 onboard measurement experiments performed in MayJune 1974 are described.

Discrete potential waves in the photoreceptors of a gastropod mollusc, Hermissenda crassicornis.
PubMed
Takeda, T
19820101
Intracellular recording of dark adapted photoreceptors of Hermissenda crassicornis (Opisthobranchia, Gastropoda, Mollusca) revealed the occurrence of depolarizing waves even after blockade of synaptic transmission and postsynaptic potentials by application of low Ca2+ and high Mg2+ solution. Dim illumination increased the frequency of depolarizing waves. These observations show that Hermissenda photoreceptors have discrete waves which have been demonstrated mainly in arthropod photoreceptors. An histogram of intervals between successive discrete waves under continuous dim illumination was exponential, which is characteristic of a Poisson process. Frequency of discrete waves increased linearly depending on numbers of incident photons to the eye. Comparison of probabilities of eliciting a response to brief dim flashes of various intensities to theoretical Poisson sum curves, together with statistical analysis, indicate that the absorption of single photon is sufficient to evoke a discrete wave. PMID:7101766

Simulating continuoustime Hamiltonian dynamics by way of a discretetime quantum walk
NASA Astrophysics Data System (ADS)
Schmitz, A. T.; Schwalm, W. A.
20160301
Much effort has been made to connect the continuoustime and discretetime quantum walks. We present a method for making that connection for a general graph Hamiltonian on a bigraph. Furthermore, such a scheme may be adapted for simulating discretized quantum models on a quantum computer. A coin operator is found for the discretetime quantum walk which exhibits the same dynamics as the continuoustime evolution. Given the spectral decomposition of the graph Hamiltonian and certain restrictions, the discretetime evolution is solved for explicitly and understood at or near important values of the parameters. Finally, this scheme is connected to past results for the 1D chain.

Entry Guidance for the Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Lu, Ping
19990101
The X33 Advanced Technology Demonstrator is a halfscale prototype developed to test the key technologies needed for a fullscale singlestage reusable launch vehicle (RLV). The X33 is a suborbital vehicle that will be launched vertically, and land horizontally. The goals of this research were to develop an alternate entry guidance scheme for the X33 in parallel to the actual X33 entry guidance algorithms, provide comparative and complementary study, and identify potential new ways to improve entry guidance performance. Toward these goals, the nominal entry trajectory is defined by a piecewise linear dragaccelerationversusenergy profile, which is in turn obtained by the solution of a semianalytical parameter optimization problem. The closedloop guidance is accomplished by tracking the nominal drag profile with primarily bankangle modulation onboard. The bankangle is commanded by a single fullenvelope nonlinear trajectory control law. Near the end of the entry flight, the guidance logic is switched to heading control in order to meet strict conditions at the terminal area energy management interface. Two methods, one on groundtrack control and the other on heading control, were proposed and examined for this phase of entry guidance where lateral control is emphasized. Trajectory dispersion studies were performed to evaluate the effectiveness of the entry guidance algorithms against a number of uncertainties including those in propulsion system, atmospheric properties, winds, aerodynamics, and propellant loading. Finally, a new trajectoryregulation method is introduced at the end as a promising precision entry guidance method. The guidance principle is very different and preliminary application in X33 entry guidance simulation showed high precision that is difficult to achieve by existing methods.

Multigrid methods for isogeometric discretization.
PubMed
Gahalaut, K P S; Kraus, J K; Tomar, S K
20130101
We present (geometric) multigrid methods for isogeometric discretization of scalar second order elliptic problems. The smoothing property of the relaxation method, and the approximation property of the intergrid transfer operators are analyzed. These properties, when used in the framework of classical multigrid theory, imply uniform convergence of twogrid and multigrid methods. Supporting numerical results are provided for the smoothing property, the approximation property, convergence factor and iterations count for V, W and Fcycles, and the linear dependence of Vcycle convergence on the smoothing steps. For two dimensions, numerical results include the problems with variable coefficients, simple multipatch geometry, a quarter annulus, and the dependence of convergence behavior on refinement levels [Formula: see text], whereas for three dimensions, only the constant coefficient problem in a unit cube is considered. The numerical results are complete up to polynomial order [Formula: see text], and for [Formula: see text] and [Formula: see text] smoothness. PMID:24511168

Discrete modelling of drapery systems
NASA Astrophysics Data System (ADS)
Thoeni, Klaus; Giacomini, Anna
20160401
Drapery systems are an efficient and costeffective measure in preventing and controlling rockfall hazards on rock slopes. The simplest form consists of a row of ground anchors along the top of the slope connected to a horizontal support cable from which a wire mesh is suspended down the face of the slope. Such systems are generally referred to as simple or unsecured draperies (Badger and Duffy 2012). Variations such as secured draperies, where a pattern of ground anchors is incorporated within the field of the mesh, and hybrid systems, where the upper part of an unsecured drapery is elevated to intercept rockfalls originating upslope of the installation, are becoming more and more popular. This work presents a discrete element framework for simulation of unsecured drapery systems and its variations. The numerical model is based on the classical discrete element method (DEM) and implemented into the opensource framework YADE (Šmilauer et al., 2010). The model takes all relevant interactions between block, drapery and slope into account (Thoeni et al., 2014) and was calibrated and validated based on fullscale experiments (Giacomini et al., 2012).The block is modelled as a rigid clump made of spherical particles which allows any shape to be approximated. The drapery is represented by a set of spherical particle with remote interactions. The behaviour of the remote interactions is governed by the constitutive behaviour of the wire and generally corresponds to a piecewise linear stressstrain relation (Thoeni et al., 2013). The same concept is used to model wire ropes. The rock slope is represented by rigid triangular elements where material properties (e.g., normal coefficient of restitution, friction angle) are assigned to each triangle. The capabilities of the developed model to simulate drapery systems and estimate the residual hazard involved with such systems is shown. References Badger, T.C., Duffy, J.D. (2012) Drapery systems. In: Turner, A.K., Schuster R

Multigrid methods for isogeometric discretization
PubMed Central
Gahalaut, K.P.S.; Kraus, J.K.; Tomar, S.K.
20130101
We present (geometric) multigrid methods for isogeometric discretization of scalar second order elliptic problems. The smoothing property of the relaxation method, and the approximation property of the intergrid transfer operators are analyzed. These properties, when used in the framework of classical multigrid theory, imply uniform convergence of twogrid and multigrid methods. Supporting numerical results are provided for the smoothing property, the approximation property, convergence factor and iterations count for V, W and Fcycles, and the linear dependence of Vcycle convergence on the smoothing steps. For two dimensions, numerical results include the problems with variable coefficients, simple multipatch geometry, a quarter annulus, and the dependence of convergence behavior on refinement levels ℓ, whereas for three dimensions, only the constant coefficient problem in a unit cube is considered. The numerical results are complete up to polynomial order p=4, and for C0 and Cp1 smoothness. PMID:24511168

Classicality in discrete Wigner functions
SciTech Connect
Cormick, Cecilia; Galvao, Ernesto F.; Gottesman, Daniel; Paz, Juan Pablo; Pittenger, Arthur O.
20060115
Gibbons et al., [Phys. Rev. A 70, 062101 (2004)] have recently defined discrete Wigner functions W to represent quantum states in a Hilbert space with finite dimension. We show that such a class of Wigner functions W can be defined so that the only pure states having nonnegative W for all such functions are stabilizer states, as conjectured by Galvao, [Phys. Rev. A 71, 042302 (2005)]. We also show that the unitaries preserving nonnegativity of W for all definitions of W in the class form a subgroup of the Clifford group. This means pure states with nonnegative W and their associated unitary dynamics are classical in the sense of admitting an efficient classical simulation scheme using the stabilizer formalism.

Determinant Expressions for Discrete Integrable Maps
NASA Astrophysics Data System (ADS)
Sogo, Kiyoshi
20060801
Explicit formulas for several discrete integrable maps with periodic boundary condition are obtained, which give the sequential time developments in a form of the quotient of successive determinants of tridiagonal matrices. We can expect that such formulas make the corresponding numerical simulations simple and stable. The cases of discrete LotkaVolterra and discrete KdV equations are demonstrated by using the common algorithm computing determinants of tridiagonal matrices.

A Comparison of ErrorCorrection Procedures on Skill Acquisition during DiscreteTrial Instruction
ERIC Educational Resources Information Center
Carroll, Regina A.; Joachim, Brad T.; St. Peter, Claire C.; Robinson, Nicole
20150101
Previous research supports the use of a variety of errorcorrection procedures to facilitate skill acquisition during discretetrial instruction. We used an adapted alternating treatments design to compare the effects of 4 commonly used errorcorrection procedures on skill acquisition for 2 children with attention deficit hyperactivity disorder…

A discrete event method for wave simulation
SciTech Connect
Nutaro, James J
20060101
This article describes a discrete event interpretation of the finite difference time domain (FDTD) and digital wave guide network (DWN) wave simulation schemes. The discrete event method is formalized using the discrete event system specification (DEVS). The scheme is shown to have errors that are proportional to the resolution of the spatial grid. A numerical example demonstrates the relative efficiency of the scheme with respect to FDTD and DWN schemes. The potential for the discrete event scheme to reduce numerical dispersion and attenuation errors is discussed.

Scalar discrete nonlinear multipoint boundary value problems
NASA Astrophysics Data System (ADS)
Rodriguez, Jesus; Taylor, Padraic
20070601
In this paper we provide sufficient conditions for the existence of solutions to scalar discrete nonlinear multipoint boundary value problems. By allowing more general boundary conditions and by imposing less restrictions on the nonlinearities, we obtain results that extend previous work in the area of discrete boundary value problems [Debra L. Etheridge, Jesus Rodriguez, Periodic solutions of nonlinear discretetime systems, Appl. Anal. 62 (1996) 119137; Debra L. Etheridge, Jesus Rodriguez, Scalar discrete nonlinear twopoint boundary value problems, J. Difference Equ. Appl. 4 (1998) 127144].

Effect of delayed reinforcement on skill acquisition during discretetrial instruction: Implications for treatmenintegrity errors in academic settings.
PubMed
Carroll, Regina A; Kodak, Tiffany; Adolf, Kari J
20160301
We used an adapted alternating treatments design to compare skill acquisition during discretetrial instruction using immediate reinforcement, delayed reinforcement with immediate praise, and delayed reinforcement for 2 children with autism spectrum disorder. Participants acquired the skills taught with immediate reinforcement; however, delayed reinforcement decreased the efficiency and effectiveness of discretetrial instruction. We discuss the importance of evaluating the influence of treatmentintegrity errors on skill acquisition during discretetrial instruction. PMID:26947579

Numerical SkipEntry Guidance
NASA Technical Reports Server (NTRS)
Tigges, Michael; Crull, Timothy; Rea, Jeremy; Johnson, Wyatt
20060101
This paper assesses a preliminary guidance and targeting strategy for accomplishing SkipEntry (SE) flight during a lunar returncapsule entry flight. One of the primary benefits of flying a SE trajectory is to provide the crew with continuous Continental United States (CONUS) landing site access throughout the lunar month. Without a SE capability, the capsule must land either in water or at one of several distributed land sites in the Southern Hemisphere for a significant portion of a lunar month using a landing and recovery scenario similar to that employed during the Apollo program. With a SE trajectory, the capsule can land either in water at a site in proximity to CONUS or at one of several distributed landing sites within CONUS, thereby simplifying the operational requirements for crew retrieval and vehicle recovery, and possibly enabling a high degree of vehicle reusability. Note that a SE capability does not require that the vehicle land on land. A SE capability enables a longerrange flight than a directentry flight, which permits the vehicle to land at a much greater distance from the Entry Interface (EI) point. This does not exclude using this approach to push the landing point to a water location in proximity of CONUS and utilizing water or airborne recovery forces.

Optofluidic control of axonal guidance
NASA Astrophysics Data System (ADS)
Gu, Ling; Ordonez, Simon; Black, Bryan; Mohanty, Samarendra K.
20130301
Significant efforts are being made for control on axonal guidance due to its importance in nerve regeneration and in the formation of functional neuronal circuitry invitro. These include several physical (topographic modification, optical force, and electric field), chemical (surface functionalization cues) and hybrid (electrochemical, photochemical etc) methods. Here, we report comparison of the effect of linear flow versus microfluidic flow produced by an opticallydriven micromotor in guiding retinal ganglion axons. A circularly polarized laser tweezers was used to hold, position and spin birefringent calcite particle near growth cone, which in turn resulted in microfluidic flow. The flow rate and resulting shearforce on axons could be controlled by a varying the power of the laser tweezers beam. The calcite particles were placed separately in one chamber and single particle was transported through microfluidic channel to another chamber containing the retina explant. In presence of flow, the turning of axons was found to strongly correlate with the direction of flow. Turning angle as high as 90° was achieved. Optofluidicmanipulation can be applied to other types of mammalian neurons and also can be extended to stimulate mechanosensing neurons.

[Recipients adverse reactions: guidance supports].
PubMed
Bazin, A
20101201
Since 1994, adverse effects of transfusion transmitted to the French haemovigilance network are registered on "efit", the database of the French agency for the safety of health products (Afssaps). In order to improve their analysis, guidance supports have been made by Afssaps working groups. Each support deals with a blood transfusion side effect and is composed of five parts including pathophysiological mechanisms, diagnostic criteria, management recommendations, etiologic investigations and rules of filing the notification form on efit. The major characteristics of sheets published or soontobe published are presented: transfusionrelated acute lung injury, transfusiontransmitted bacterial infection, nonhaemolytic febrile reaction, allergic reaction, transfusionassociated circulatory overload, hypotensive transfusion reaction, alloimmunization, erythrocyte incompatibility reaction and hemosiderosis. These new supports give relevant guidelines allowing a better analysis and evaluation of recipients' adverse reactions, particularly their diagnosis, gravity and accountability. They could also initiate studies in European and international haemovigilance and transfusion networks. PMID:21051267

Adaptive SPECT
PubMed Central
Barrett, Harrison H.; Furenlid, Lars R.; Freed, Melanie; Hesterman, Jacob Y.; Kupinski, Matthew A.; Clarkson, Eric; Whitaker, Meredith K.
20080101
Adaptive imaging systems alter their dataacquisition configuration or protocol in response to the image information received. An adaptive pinhole singlephoton emission computed tomography (SPECT) system might acquire an initial scout image to obtain preliminary information about the radiotracer distribution and then adjust the configuration or sizes of the pinholes, the magnifications, or the projection angles in order to improve performance. This paper briefly describes two smallanimal SPECT systems that allow this flexibility and then presents a framework for evaluating adaptive systems in general, and adaptive SPECT systems in particular. The evaluation is in terms of the performance of linear observers on detection or estimation tasks. Expressions are derived for the ideal linear (Hotelling) observer and the ideal linear (Wiener) estimator with adaptive imaging. Detailed expressions for the performance figures of merit are given, and possible adaptation rules are discussed. PMID:18541485

Guidance and control of swarms of spacecraft
NASA Astrophysics Data System (ADS)
Morgan, Daniel James
There has been considerable interest in formation flying spacecraft due to their potential to perform certain tasks at a cheaper cost than monolithic spacecraft. Formation flying enables the use of smaller, cheaper spacecraft that distribute the risk of the mission. Recently, the ideas of formation flying have been extended to spacecraft swarms made up of hundreds to thousands of 100gramclass spacecraft known as femtosatellites. The large number of spacecraft and limited capabilities of each individual spacecraft present a significant challenge in guidance, navigation, and control. This dissertation deals with the guidance and control algorithms required to enable the flight of spacecraft swarms. The algorithms developed in this dissertation are focused on achieving two main goals: swarm keeping and swarm reconfiguration. The objectives of swarm keeping are to maintain bounded relative distances between spacecraft, prevent collisions between spacecraft, and minimize the propellant used by each spacecraft. Swarm reconfiguration requires the transfer of the swarm to a specific shape. Like with swarm keeping, minimizing the propellant used and preventing collisions are the main objectives. Additionally, the algorithms required for swarm keeping and swarm reconfiguration should be decentralized with respect to communication and computation so that they can be implemented on femtosats, which have limited hardware capabilities. The algorithms developed in this dissertation are concerned with swarms located in low Earth orbit. In these orbits, Earth oblateness and atmospheric drag have a significant effect on the relative motion of the swarm. The complicated dynamic environment of low Earth orbits further complicates the swarmkeeping and swarmreconfiguration problems. To better develop and test these algorithms, a nonlinear, relative dynamic model with J2 and drag perturbations is developed. This model is used throughout this dissertation to validate the algorithms

78 FR 54949  Major Project Financial Plan Guidance
Federal Register 2010, 2011, 2012, 2013, 2014
20130906
... TRANSPORTATION Federal Highway Administration Major Project Financial Plan Guidance AGENCY: Federal Highway... Major Project Financial Plan Guidance outlining the procedures the FHWA will follow when reviewing and approving Financial Plans. The proposed Major Project Financial Plan Guidance incorporates changes...

Novel Approaches to Adaptive Angular Approximations in Computational Transport
SciTech Connect
Marvin L. Adams; Igor Carron; Paul Nelson
20060604
The particletransport equation is notoriously difficult to discretize accurately, largely because the solution can be discontinuous in every variable. At any given spatial position and energy E, for example, the transport solution can be discontinuous at an arbitrary number of arbitrary locations in the direction domain. Even if the solution is continuous it is often devoid of smoothness. This makes the direction variable extremely difficult to discretize accurately. We have attacked this problem with adaptive discretizations in the angle variables, using two distinctly different approaches. The first approach used wavelet function expansions directly and exploited their ability to capture sharp local variations. The second used discrete ordinates with a spatially varying quadrature set that adapts to the local solution. The first approach is very different from that in today’s transport codes, while the second could conceivably be implemented in such codes. Both approaches succeed in reducing angular discretization error to any desired level. The work described and results presented in this report add significantly to the understanding of angular discretization in transport problems and demonstrate that it is possible to solve this important longstanding problem in deterministic transport. Our results show that our adaptive discreteordinates (ADO) approach successfully: 1) Reduces angular discretization error to userselected “tolerance” levels in a variety of difficult test problems; 2) Achieves a given error with significantly fewer unknowns than nonadaptive discrete ordinates methods; 3) Can be implemented within standard discreteordinates solution techniques, and thus could generate a significant impact on the field in a relatively short time. Our results show that our adaptive wavelet approach: 1) Successfully reduces the angular discretization error to arbitrarily small levels in a variety of difficult test problems, even when using the

Optimal guidance law in quantum mechanics
SciTech Connect
Yang, CiannDong Cheng, LiehLieh
20131115
Following de Broglie’s idea of a pilot wave, this paper treats quantum mechanics as a problem of stochastic optimal guidance law design. The guidance scenario considered in the quantum world is that an electron is the flight vehicle to be guided and its accompanying pilot wave is the guidance law to be designed so as to guide the electron to a random target driven by the Wiener process, while minimizing a costtogo function. After solving the stochastic optimal guidance problem by differential dynamic programming, we point out that the optimal pilot wave guiding the particle’s motion is just the wavefunction Ψ(t,x), a solution to the Schrödinger equation; meanwhile, the closedloop guidance system forms a complex state–space dynamics for Ψ(t,x), from which quantum operators emerge naturally. Quantum trajectories under the action of the optimal guidance law are solved and their statistical distribution is shown to coincide with the prediction of the probability density function Ψ{sup ∗}Ψ.  Highlights: •Treating quantum mechanics as a pursuitevasion game. •Reveal an interesting analogy between guided flight motion and guided quantum motion. •Solve optimal quantum guidance problem by dynamic programming. •Gives a formal proof of de Broglie–Bohm’s idea of a pilot wave. •The optimal pilot wave is shown to be a wavefunction solved from Schrödinger equation.

Evaluation of lowdose limits in 3D2D rigid registration for surgical guidance
NASA Astrophysics Data System (ADS)
Uneri, A.; Wang, A. S.; Otake, Y.; Kleinszig, G.; Vogt, S.; Khanna, A. J.; Gallia, G. L.; Gokaslan, Z. L.; Siewerdsen, J. H.
20140901
An algorithm for intensitybased 3D2D registration of CT and Carm fluoroscopy is evaluated for use in surgical guidance, specifically considering the lowdose limits of the fluoroscopic xray projections. The registration method is based on a framework using the covariance matrix adaptation evolution strategy (CMAES) to identify the 3D patient pose that maximizes the gradient information similarity metric. Registration performance was evaluated in an anthropomorphic head phantom emulating intracranial neurosurgery, using target registration error (TRE) to characterize accuracy and robustness in terms of 95% confidence upper bound in comparison to that of an infrared surgical tracking system. Three clinical scenarios were considered: (1) singleview image + guidance, wherein a single xray projection is used for visualization and 3D2D guidance; (2) dualview image + guidance, wherein one projection is acquired for visualization, combined with a second (lowerdose) projection acquired at a different Carm angle for 3D2D guidance; and (3) dualview guidance, wherein both projections are acquired at low dose for the purpose of 3D2D guidance alone (not visualization). In each case, registration accuracy was evaluated as a function of the entrance surface dose associated with the projection view(s). Results indicate that images acquired at a dose as low as 4 μGy (approximately onetenth the dose of a typical fluoroscopic frame) were sufficient to provide TRE comparable or superior to that of conventional surgical tracking, allowing 3D2D guidance at a level of dose that is at most 10% greater than conventional fluoroscopy (scenario #2) and potentially reducing the dose to approximately 20% of the level in a conventional fluoroscopically guided procedure (scenario #3).

Adaptive Dynamic Bayesian Networks
SciTech Connect
Ng, B M
20071026
A discretetime Markov process can be compactly modeled as a dynamic Bayesian network (DBN)a graphical model with nodes representing random variables and directed edges indicating causality between variables. Each node has a probability distribution, conditional on the variables represented by the parent nodes. A DBN's graphical structure encodes fixed conditional dependencies between variables. But in realworld systems, conditional dependencies between variables may be unknown a priori or may vary over time. Model errors can result if the DBN fails to capture all possible interactions between variables. Thus, we explore the representational framework of adaptive DBNs, whose structure and parameters can change from one time step to the next: a distribution's parameters and its set of conditional variables are dynamic. This work builds on recent work in nonparametric Bayesian modeling, such as hierarchical Dirichlet processes, infinitestate hidden Markov networks and structured priors for Bayes net learning. In this paper, we will explain the motivation for our interest in adaptive DBNs, show how popular nonparametric methods are combined to formulate the foundations for adaptive DBNs, and present preliminary results.

Aeroassist flight experiment guidance Quiet Time
NASA Technical Reports Server (NTRS)
Striepe, Scott A.; Suit, William T.
19880101
The science experiments for the Aeroassist Flight Experiment (AFE) will be greatly enhanced by taking measurements with no Reaction Control System (RCS) contamination just before perigee. Methods of modifying the AFE guidance to accomplish this are discussed. Several methods that could give up to 30 seconds of quiet time were investigated and the results of these guidance modifications shown. A 20 second quiet time is definitely possible and a 30 second quiet time may be possible if the guidance can be inactive past perigee. Some of the most significant being the criterion for determining if the mission is threatened. A limited followon test program is outlined.

Navigating through 'a labyrinth' of guidance.
PubMed
Pearson, Susan
20140901
Devising a strategy to deliver safe water to thousands of outlets spread across numerous buildings is always going to be a challenge, so how do you navigate your way through a bewildering labyrinth of sometimes contradictory guidance documents? Is there, in fact, simply too much guidance? Posing this question at a recent oneday conference on waterborne infections in healthcare facilities, Paul Nolan, authorised water engineer (AE), and operations manager for PFI provider, Lend Lease, took delegates through a review of the latest guidance and regulations, as Susan Pearson reports. PMID:25282983

76 FR 58398  Revised Guidance on Marketed Unapproved Drugs; Compliance Policy Guide Sec. 440.100; Marketed New...
Federal Register 2010, 2011, 2012, 2013, 2014
20110921
...The Food and Drug Administration (FDA) is announcing the availability of a revised guidance entitled ``Marketed Unapproved DrugsCompliance Policy Guide Sec. 440.100, Marketed New Drugs Without Approved NDAs or ANDAs'' (CPG 440.100). CPG 440.100 describes how FDA intends to exercise its enforcement discretion with regard to drug products marketed in the United States that do not have required......

Discretization vs. Rounding Error in Euler's Method
ERIC Educational Resources Information Center
Borges, Carlos F.
20110101
Euler's method for solving initial value problems is an excellent vehicle for observing the relationship between discretization error and rounding error in numerical computation. Reductions in stepsize, in order to decrease discretization error, necessarily increase the number of steps and so introduce additional rounding error. The problem is…

Discrete/PWM BallastResistor Controller
NASA Technical Reports Server (NTRS)
King, Roger J.
19940101
Circuit offers low switching loss and automatic compensation for failure of ballast resistor. Discrete/PWM ballastresistor controller improved shunt voltageregulator circuit designed to supply power from highresistance source to lowimpedance bus. Provides both coarse discrete voltage levels (by switching of ballast resistors) and continuous fine control of voltage via pulsewidth modulation.

Discreteness and Gradience in Intonational Contrasts.
ERIC Educational Resources Information Center
Gussenhoven, Carlos
19990101
Three experimental techniques that can be used to investigate the gradient of discrete nature of intonational differences, the semantic task, the imitation task, and the pitch range task are discussed and evaluated. It is pointed out that categorical perception is a sufficient but not a necessary, property of phonological discreteness. (Author/VWL)

Current Density and Continuity in Discretized Models
ERIC Educational Resources Information Center
Boykin, Timothy B.; Luisier, Mathieu; Klimeck, Gerhard
20100101
Discrete approaches have long been used in numerical modelling of physical systems in both research and teaching. Discrete versions of the Schrodinger equation employing either one or several basis functions per mesh point are often used by senior undergraduates and beginning graduate students in computational physics projects. In studying…

Discrete Fractional Diffusion Equation of Chaotic Order
NASA Astrophysics Data System (ADS)
Wu, GuoCheng; Baleanu, Dumitru; Xie, HePing; Zeng, ShengDa
Discrete fractional calculus is suggested in diffusion modeling in porous media. A variableorder fractional diffusion equation is proposed on discrete time scales. A function of the variable order is constructed by a chaotic map. The model shows some new random behaviors in comparison with other variableorder cases.

76 FR 43332  Guidance for Industry and Food and Drug Administration Staff; Class II Special Controls Guidance...
Federal Register 2010, 2011, 2012, 2013, 2014
20110720
...; Class II Special Controls Guidance Document: Focused Ultrasound Stimulator System for Aesthetic Use... Guidance Document: Focused Ultrasound Stimulator System for Aesthetic Use.'' This guidance document describes a means by which focused ultrasound stimulator systems for aesthetic use may comply with...

Travel guidance system for vehicles
SciTech Connect
Takanabe, K.; Yamamoto, M.; Ito, K.; Fujinami, H.
19870224
A travel guidance system is described for vehicles including: a heading sensor for detecting a direction of movement of a vehicle; a distance sensor for detecting a distance traveled by the vehicle; a map data storage medium preliminarily storing map data; a control unit for receiving a heading signal from the heading sensor and a distance signal from the distance sensor to successively compute a present position of the vehicle and for generating video signals corresponding to display data including map data from the map data storage medium and data of the present position; and a display having first and second display portions and responsive to the video signals from the control unit to display on the first display portion a map and a present portion mark, in which: the map data storage medium comprises means for preliminarily storing administrative division name data and landmark data; and the control unit comprises: landmark display means for: (1) determining a landmark closest to the present position, (2) causing a position of the landmark to be displayed on the map and (3) retrieving a landmark massage concerning the landmark from the storage medium to cause the display to display the landmark message on the second display portion; division name display means for retrieving the name of an administrative division to which the present position belongs from the storage medium and causing the display to display a division name message on the second display portion; and selection means for selectively actuating at least one of the landmark display means and the division name display means.

Discrete elements method of neutral particle transport
SciTech Connect
Mathews, K.A.
19830101
A new discrete elements (L/sub N/) transport method is derived and compared to the discrete ordinates S/sub N/ method, theoretically and by numerical experimentation. The discrete elements method is more accurate than discrete ordinates and strongly ameliorates ray effects for the practical problems studied. The discrete elements method is shown to be more cost effective, in terms of execution time with comparable storage to attain the same accuracy, for a onedimensional test case using linear characteristic spatial quadrature. In a twodimensional test case, a vacuum duct in a shield, L/sub N/ is more consistently convergent toward a Monte Carlo benchmark solution than S/sub N/, using step characteristic spatial quadrature. An analysis of the interaction of angular and spatial quadrature in xygeometry indicates the desirability of using linear characteristic spatial quadrature with the L/sub N/ method.

Active control of turbomachine discrete tones
NASA Astrophysics Data System (ADS)
Fleeter, Sanford
This paper was directed at active control of discrete frequency noise generated by subsonic blade rows through cancellation of the blade row interaction generated propagating acoustic waves. First discrete frequency noise generated by a rotor and stator in a duct was analyzed to determine the propagating acoustic pressure waves. Then a mathematical model was developed to analyze and predict the active control of discrete frequency noise generated by subsonic blade rows through cancellation of the propagating acoustic waves, accomplished by utilizing oscillating airfoil surfaces to generate additional control propagating pressure waves. These control waves interact with the propagating acoustic waves, thereby, in principle, canceling the acoustic waves and thus, the far field discrete frequency tones. This model was then applied to a fan exit guide vane to investigate active airfoil surface techniques for control of the propagating acoustic waves, and thus the far field discrete frequency tones, generated by blade row interactions.

Discrete breathers in graphane: Effect of temperature
NASA Astrophysics Data System (ADS)
Baimova, J. A.; Murzaev, R. T.; Lobzenko, I. P.; Dmitriev, S. V.; Zhou, Kun
20160501
The discrete breathers in graphane in thermodynamic equilibrium in the temperature range 50600 K are studied by molecular dynamics simulation. A discrete breather is a hydrogen atom vibrating along the normal to a sheet of graphane at a high amplitude. As was found earlier, the lifetime of a discrete breather at zero temperature corresponds to several tens of thousands of vibrations. The effect of temperature on the decay time of discrete breathers and the probability of their detachment from a sheet of graphane are studied in this work. It is shown that closely spaced breathers can exchange energy with each other at zero temperature. The data obtained suggest that thermally activated discrete breathers can be involved in the dehydrogenation of graphane, which is important for hydrogen energetics.

Seipin Is a Discrete Homooligomer†
PubMed Central
Binns, Derk; Lee, SungKyung; Hilton, Christopher L.; Jiang, QiuXing; Goodman, Joel M.
20110101
Seipin is a transmembrane protein that resides in the endoplasmic reticulum and concentrates at junctions between the ER and cytosolic lipid droplets. Mutations in the human seipin gene, including the missense mutation A212P, lead to congenital generalized lipodystrophy (CGL), characterized by the lack of normal adipose tissue and accumulation of fat in liver and muscles. In both yeast and CGL patient fibroblasts, seipin is required for normal lipid droplet morphology; in its absence droplets appear to bud abnormally from the ER. Here we report the first purification and physical characterization of seipin. Yeast seipin is in a large discrete protein complex. Affinity purification demonstrated that seipin is the main if not exclusive protein in the complex. Detergent sucrose gradients in H2O, and D2O and gel filtration were used to determine the size of the seipin complex and account for detergent binding. Both seipinmyc13 (seipin fused to 13 tandem copies of the myc epitope) expressed from the endogenous promoter and overexpressed seipinmCherry form ~500 kDa proteins consisting of about 9 copies of seipin. The yeast orthologue of the human A212P allele forms only smaller complexes and is unstable; we hypothesize that this accounts for its null phenotype in humans. Seipin appears as a toroid by negative staining electron microscopy. We speculate that seipin plays at least a structural role in organizing droplets or in communication between droplets and ER. PMID:21062080

Distinct roles for secreted semaphorin signaling in spinal motor axon guidance.
PubMed
Huber, Andrea B; Kania, Artur; Tran, Tracy S; Gu, Chenghua; De Marco Garcia, Natalia; Lieberam, Ivo; Johnson, Dontais; Jessell, Thomas M; Ginty, David D; Kolodkin, Alex L
20051222
Neuropilins, secreted semaphorin coreceptors, are expressed in discrete populations of spinal motor neurons, suggesting they provide critical guidance information for the establishment of functional motor circuitry. We show here that motor axon growth and guidance are impaired in the absence of Sema3ANpn1 signaling. Motor axons enter the limb precociously, showing that Sema3A controls the timing of motor axon ingrowth to the limb. Lateral motor column (LMC) motor axons within spinal nerves are defasciculated as they grow toward the limb and converge in the plexus region. Medial and lateral LMC motor axons show dorsoventral guidance defects in the forelimb. In contrast, Sema3FNpn2 signaling guides the axons of a medial subset of LMC neurons to the ventral limb, but plays no major role in regulating their fasciculation. Thus, Sema3ANpn1 and Sema3FNpn2 signaling control distinct steps of motor axon growth and guidance during the formation of spinal motor connections. PMID:16364899

7 CFR 1794.7  Guidance.
Code of Federal Regulations, 2011 CFR
20110101
...)); RUS Bulletin 1794A601 provides guidance in preparing the ER for proposed actions which require EAs... (§ 1794.22(b)) and EAs (§ 1794.23(b)). A copy of this bulletin is available upon request by contacting...

7 CFR 1794.7  Guidance.
Code of Federal Regulations, 2013 CFR
20130101
...)); RUS Bulletin 1794A601 provides guidance in preparing the ER for proposed actions which require EAs... (§ 1794.22(b)) and EAs (§ 1794.23(b)). A copy of this bulletin is available upon request by contacting...

7 CFR 1794.7  Guidance.
Code of Federal Regulations, 2014 CFR
20140101
...)); RUS Bulletin 1794A601 provides guidance in preparing the ER for proposed actions which require EAs... (§ 1794.22(b)) and EAs (§ 1794.23(b)). A copy of this bulletin is available upon request by contacting...

7 CFR 1794.7  Guidance.
Code of Federal Regulations, 2012 CFR
20120101
...)); RUS Bulletin 1794A601 provides guidance in preparing the ER for proposed actions which require EAs... (§ 1794.22(b)) and EAs (§ 1794.23(b)). A copy of this bulletin is available upon request by contacting...

Delta launch vehicle inertial guidance system (DIGS)
NASA Technical Reports Server (NTRS)
Duck, K. I.
19730101
The Delta inertial guidance system, part of the Delta launch vehicle improvement effort, has been flown on three launches and was found to perform as expected for a variety of mission profiles and vehicle configurations.

21 CFR 316.50  Guidance documents.
Code of Federal Regulations, 2010 CFR
20100401
... USE ORPHAN DRUGS Availability of Information § 316.50 Guidance documents. FDA's Office of Orphan... Federal Register. A request for a copy of the list should be directed to the Office of Orphan...

7 CFR 1794.7  Guidance.
Code of Federal Regulations, 2010 CFR
20100101
... Analysis, Stop 1522, 1400 Independence Avenue, SW., Washington, DC 202501522. (b) Water and waste program... appropriate State Director. State Directors may provide supplemental guidance to meet state and local laws...

77 FR 14403  Guidance for Industry and Food and Drug Administration Staff; Class II Special Controls Guidance...
Federal Register 2010, 2011, 2012, 2013, 2014
20120309
...: Norovirus Serological Reagents.'' This guidance document describes a means by which norovirus serological... by following the recommendations in the guidance document or by some other means that...

Online trajectory planning and guidance for reusable launch vehicles in the terminal area
NASA Astrophysics Data System (ADS)
Lan, XueJing; Liu, Lei; Wang, YongJi
20160101
A guidance scheme has been proposed based on a new online trajectory planning algorithm for an unpowered reusable launch vehicle (RLV) in the terminal area energy management (TAEM) phase. The trajectory planning algorithm is able to rapidly generate a feasible path from the current state to a desired state at approach and landing interface (ALI) based on the dynamic pressure profile and new ground track geometry. Simple guidance laws are used to keep the RLV flying along the reference path which can be adjusted online by five related parameters. Then, the effectiveness and adaptability of the proposed TAEM guidance scheme is demonstrated by numerical trials with variations in the initial energy, position and aerodynamic performance.

Soil screening guidance: User`s guide
SciTech Connect
19960401
The Soil Screening Guidance is a tool that the U.S. Environmental Protection Agency (EPA) developed to help standardize and accelerate the evaluation and cleanup of contaminated soils at sites on the National Priorities List (NPL) with future residential land use. This guidance provides a methodology for environmental science/engineering professionals to calculate riskbased, sitespecific, soil screening levels (SSLs) for contaminants in soil that may be used to identify areas needing further investigation at NPL sites.

Compatible Spatial Discretizations for Partial Differential Equations
SciTech Connect
Arnold, Douglas, N, ed.
20041125
From May 1115, 2004, the Institute for Mathematics and its Applications held a hot topics workshop on Compatible Spatial Discretizations for Partial Differential Equations. The numerical solution of partial differential equations (PDE) is a fundamental task in science and engineering. The goal of the workshop was to bring together a spectrum of scientists at the forefront of the research in the numerical solution of PDEs to discuss compatible spatial discretizations. We define compatible spatial discretizations as those that inherit or mimic fundamental properties of the PDE such as topology, conservation, symmetries, and positivity structures and maximum principles. A wide variety of discretization methods applied across a wide range of scientific and engineering applications have been designed to or found to inherit or mimic intrinsic spatial structure and reproduce fundamental properties of the solution of the continuous PDE model at the finite dimensional level. A profusion of such methods and concepts relevant to understanding them have been developed and explored: mixed finite element methods, mimetic finite differences, support operator methods, control volume methods, discrete differential forms, Whitney forms, conservative differencing, discrete Hodge operators, discrete Helmholtz decomposition, finite integration techniques, staggered grid and dual grid methods, etc. This workshop seeks to foster communication among the diverse groups of researchers designing, applying, and studying such methods as well as researchers involved in practical solution of large scale problems that may benefit from advancements in such discretizations; to help elucidate the relations between the different methods and concepts; and to generally advance our understanding in the area of compatible spatial discretization methods for PDE. Particular points of emphasis included: + Identification of intrinsic properties of PDE models that are critical for the fidelity of numerical

An extension of the OpenModelica compiler for using Modelica models in a discrete event simulation
DOE PAGESBeta
Nutaro, James
20141103
In this article, a new backend and runtime system is described for the OpenModelica compiler. This new backend transforms a Modelica model into a module for the adevs discrete event simulation package, thereby extending adevs to encompass complex, hybrid dynamical systems. The new runtime system that has been built within the adevs simulation package supports models with stateevents and timeevents and that comprise differentialalgebraic systems with high index. Finally, although the procedure for effecting this transformation is based on adevs and the Discrete Event System Specification, it can be adapted to any discrete event simulation package.

Turbulent OutputBased Anisotropic Adaptation
NASA Technical Reports Server (NTRS)
Park, Michael A.; Carlson, JanRenee
20100101
Controlling discretization error is a remaining challenge for computational fluid dynamics simulation. Grid adaptation is applied to reduce estimated discretization error in drag or pressure integral output functions. To enable application to high O(10(exp 7)) Reynolds number turbulent flows, a hybrid approach is utilized that freezes the nearwall boundary layer grids and adapts the grid away from the no slip boundaries. The hybrid approach is not applicable to problems with under resolved initial boundary layer grids, but is a powerful technique for problems with important offbody anisotropic features. Supersonic nozzle plume, turbulent flat plate, and shockboundary layer interaction examples are presented with comparisons to experimental measurements of pressure and velocity. Adapted grids are produced that resolve offbody features in locations that are not known a priori.

Stochastic Discrete Equation Method (sDEM) for twophase flows
SciTech Connect
Abgrall, R.; Congedo, P.M.; Geraci, G.; Rodio, M.G.
20151015
A new scheme for the numerical approximation of a fiveequation model taking into account Uncertainty Quantification (UQ) is presented. In particular, the Discrete Equation Method (DEM) for the discretization of the fiveequation model is modified for including a formulation based on the adaptive SemiIntrusive (aSI) scheme, thus yielding a new intrusive scheme (sDEM) for simulating stochastic twophase flows. Some reference testcases are performed in order to demonstrate the convergence properties and the efficiency of the overall scheme. The propagation of initial conditions uncertainties is evaluated in terms of mean and variance of several thermodynamic properties of the two phases.

A multidimensional vector spherical harmonics discrete ordinate method for atmospheric radiative transfer
NASA Astrophysics Data System (ADS)
Doicu, Adrian; Efremenko, Dmitry; Trautmann, Thomas
20130301
The multidimensional scalar Spherical Harmonics Discrete Ordinate Method (SHDOM) is extended to the vector case. The vector model uses complex and real generalized spherical harmonics in the energetic representation of the Stokes vector, and retains some powerful features of the scalar model, as for example, the combination of the generalized spherical harmonic and the discrete ordinate representations of the radiance field, the use of a linear short characteristic method for computing the cornerpoint values of the Stokes vector, and the application of the adaptive grid technique. Results illustrating the accuracy of the vector model are shown for realistic simulated clouds.

On the equivalence of the discrete nonlinear Schrödinger equation and the discrete isotropic Heisenberg magnet
NASA Astrophysics Data System (ADS)
Hoffmann, Tim
20000101
The equivalence of the discrete isotropic Heisenberg magnet (IHM) model and the discrete nonlinear Schrödinger equation (NLSE) given by Ablowitz and Ladik is shown. This is used to derive the equivalence of their discretization with the one by Izgerin and Korepin. Moreover a doubly discrete IHM is presented that is equivalent to Ablowitz' and Ladiks doubly discrete NLSE.

Discrete symmetries and de Sitter spacetime
SciTech Connect
Cotăescu, Ion I. Pascu, Gabriel
20141124
Aspects of the ambiguity in defining quantum modes on de Sitter spacetime using a commuting system composed only of differential operators are discussed. Discrete symmetries and their actions on the wavefunction in commonly used coordinate charts are reviewed. It is argued that the system of commuting operators can be supplemented by requiring the invariance of the wavefunction to combined discrete symmetries a criterion which selects a single state out of the αvacuum family. Two such members of this family are singled out by particular combined discrete symmetries states between which exists a wellknown thermality relation.

Discrete flavour symmetries from the Heisenberg group
NASA Astrophysics Data System (ADS)
Floratos, E. G.; Leontaris, G. K.
20160401
Nonabelian discrete symmetries are of particular importance in model building. They are mainly invoked to explain the various fermion mass hierarchies and forbid dangerous superpotential terms. In string models they are usually associated to the geometry of the compactification manifold and more particularly to the magnetised branes in toroidal compactifications. Motivated by these facts, in this note we propose a unified framework to construct representations of finite discrete family groups based on the automorphisms of the discrete and finite Heisenberg group. We focus in particular, on the PSL2 (p) groups which contain the phenomenologically interesting cases.

Highaccuracy discrete positioning device
NASA Technical Reports Server (NTRS)
Brooks, John J. (Inventor)
19940101
An article (30) is controllably and precisely positioned at one of three discrete locations defined by a linkage. The positioning apparatus includes two independently driven cranks (34, 42), with a link (50) pivotably connected between the two cranks (34, 42). Another connector (44) is pivotably connected between one of the cranks (34 or 42) and the article (30) to be positioned. The cranks (34, 42) are rotationally adjusted so that the pivot points (52, 54) of the link (50) are collinear with the axes of rotation of the cranks (40, 48), thereby defining one of the three discrete locations. Additional cranks and links can be provided to define additional discrete locations.

Guidance for Humansystem Interfaces to Automatic Systems
SciTech Connect
O'Hara, J.M.; Higgins, J.; Stephen Fleger; Valerie Barnes
20100927
Automation is ubiquitous in modern complex systems, and commercial nuclear power plants are no exception. Automation is applied to a wide range of functions, including monitoring and detection, situation assessment, response planning, and response implementation. Automation has become a 'team player' supporting personnel in nearly all aspects of system operation. In light of its increasing use and importance in new and futureplants, guidance is needed to conduct safety reviews of the operator's interface with automation. The objective of this research was to develop such guidance. We first characterized the important HFE aspects of automation, including six dimensions: Levels, functions, processes, modes, flexibility, and reliability. Next, we reviewed literature on the effects of all of these aspects of automation on human performance, and on the design of humansystem interfaces (HSIs). Then, we used this technical basis established from the literature to identify general principles for humanautomation interaction and to develop review guidelines. The guidelines consist of the following seven topics: Automation displays, interaction and control, automation modes, automation levels, adaptive automation, error tolerance and failure management, and HSI integration.

Cocaineinduced expression changes of axon guidance molecules in the adult rat brain.
PubMed
Bahi, Amine; Dreyer, JeanLuc
20050201
Administration of drugs of abuse induces strong molecular adaptations and plasticity within the mesolimbic dopamine (DA) system, a pathway essential for rewardseeking behavior. Little is known about the specific targets involved in this neuroadaptation process, but there are indications that cocaine and other drugs of abuse share the ability to alter the morphology of neuronal dendrites and spines, the primary site of excitatory synapses in the brain. Axon guidance molecules, the very molecular cues that regulate the formation of axontarget connections during development, may mediate these alterations. To test this hypothesis, we investigated mRNA expression changes of 39 axon guidance molecules, including 17 Semaphorins, 12 Ephs, 8 Ephrins, and 2 neuropilins in the mesolimbic dopamine system of cocainetreated animals under different paradigms by mean of DNAMicroarray and quantitative realtime PCR. In all cases, strong changes in gene expression are observed, yielding to up or downregulation of these axon guidance molecules. Our data suggest that cocaine treatment induces activation of a complex program of synaptic rearrangements, which may partly recapitulate the plastic changes occurring during development, and may underlie the important neuroplastic adaptations that occur in the reward and memoryrelated brain centers following drug action. We conclude that in some brain regions, exposure to psychomotorstimulant drugs produce expression changes in axon guidance molecules, which may contribute to cognitive deficits associated with drug abuse. PMID:15691709

Current Brachytherapy Quality Assurance Guidance: Does It Meet the Challenges of Emerging ImageGuided Technologies?
SciTech Connect
Williamson, Jeffrey F.
20080501
In the past decade, brachytherapy has shifted from the traditional surgical paradigm to more modern threedimensional imagebased planning and delivery approaches. The role of intraoperative and multimodality imagebased planning is growing. Published American Association of Physicists in Medicine, American College of Radiology, European Society for Therapeutic Radiology and Oncology, and International Atomic Energy Agency quality assurance (QA) guidelines largely emphasize the QA of planning and delivery devices rather than processes. These protocols have been designed to verify compliance with major performance specifications and are not risk based. With some exceptions, complete and clinically practical guidance exists for sources, QA instrumentation, nonimagebased planning systems, applicators, remote afterloading systems, dosimetry, and calibration. Updated guidance is needed for intraoperative imaging systems and imagebased planning systems. For nonimagebased brachytherapy, the American Association of Physicists in Medicine Task Group reports 56 and 59 provide reasonable guidance on procedurespecific process flow and QA. However, improved guidance is needed even for established procedures such as ultrasoundguided prostate implants. Adaptive replanning in brachytherapy faces unsolved problems similar to that of imageguided adaptive external beam radiotherapy.

Variationally consistent discretization schemes and numerical algorithms for contact problems
NASA Astrophysics Data System (ADS)
Wohlmuth, Barbara
We consider variationally consistent discretization schemes for mechanical contact problems. Most of the results can also be applied to other variational inequalities, such as those for phase transition problems in porous media, for plasticity or for option pricing applications from finance. The starting point is to weakly incorporate the constraint into the setting and to reformulate the inequality in the displacement in terms of a saddlepoint problem. Here, the Lagrange multiplier represents the surface forces, and the constraints are restricted to the boundary of the simulation domain. Having a uniform infsup bound, one can then establish optimal loworder a priori convergence rates for the discretization error in the primal and dual variables. In addition to the abstract framework of linear saddlepoint theory, complementarity terms have to be taken into account. The resulting inequality system is solved by rewriting it equivalently by means of the nonlinear complementarity function as a system of equations. Although it is not differentiable in the classical sense, semismooth Newton methods, yielding superlinear convergence rates, can be applied and easily implemented in terms of a primaldual active set strategy. Quite often the solution of contact problems has a low regularity, and the efficiency of the approach can be improved by using adaptive refinement techniques. Different standard types, such as residual and equilibratedbased a posteriori error estimators, can be designed based on the interpretation of the dual variable as Neumann boundary condition. For the fully dynamic setting it is of interest to apply energypreserving timeintegration schemes. However, the differential algebraic character of the system can result in high oscillations if standard methods are applied. A possible remedy is to modify the fully discretized system by a local redistribution of the mass. Numerical results in two and three dimensions illustrate the wide range of

Cone beam CT guidance provides superior accuracy for complex needle paths compared with CT guidance
PubMed Central
Braak, S J; Fütterer, J J; van Strijen, M J L; Hoogeveen, Y L; de Lange, F; Schultze Kool, L J
20130101
Objective: To determine the accuracy of cone beam CT (CBCT) guidance and CT guidance in reaching small targets in relation to needle path complexity in a phantom. Methods: CBCT guidance combines threedimensional CBCT imaging with fluoroscopy overlay and needle planning software to provide realtime needle guidance. The accuracy of needle positioning, quantified as deviation from a target, was assessed for inplane, angulated and double angulated needle paths. Four interventional radiologists reached four targets along the three paths using CBCT and CT guidance. Accuracies were compared between CBCT and CT for each needle path and between the three approaches within both modalities. The effect of user experience in CBCT guidance was also assessed. Results: Accuracies for CBCT were significantly better than CT for the double angulated needle path (2.2 vs 6.7 mm, p<0.001) for all radiologists. CBCT guidance showed no significant differences between the three approaches. For CT, deviations increased with increasing needle path complexity from 3.3 mm for the inplane placements to 4.4 mm (p=0.007) and 6.7 mm (p<0.001) for the angulated and double angulated CTguided needle placements, respectively. For double angulated needle paths, experienced CBCT users showed consistently higher accuracies than trained users [1.8 mm (range 1.2–2.2) vs 3.3 mm (range 2.1–7.2) deviation from target, respectively; p=0.003]. Conclusion: In terms of accuracy, CBCT is the preferred modality, irrespective of the level of user experience, for more difficult guidance procedures requiring double angulated needle paths as in oncological interventions. Advances in knowledge: Accuracy of CBCT guidance has not been discussed before. CBCT guidance allows accurate needle placement irrespective of needle path complexity. For angulated and doubleangulated needle paths, CBCT is more accurate than CT guidance. PMID:23913308

Putting the t in tools: a roadmap for implementation of new global and regional transgender guidance.
PubMed
Wolf, R Cameron; Adams, Darrin; Dayton, Robyn; Verster, Annette; Wong, Joe; Romero, Marcela; Mazin, Rafael; Settle, Edmund; Sladden, Tim; Keatley, JoAnne
20160101
Transgender (trans) activists and global health partners have collaborated to develop new tools and guidance for assessing and addressing HIV and other health needs within trans populations. Trans women experience a heavy burden of HIV and other sexually transmitted infections (STIs), high incidence of violence and difficulties accessing genderaffirming services. At the same time, little has been published on trans men's health, HIV issues, needs and experiences. Young trans people are especially marginalized and vulnerable, with few programmes and services specifically tailored to their needs. Transspecific data and guidance are needed to adapt the global response to HIV to meet the needs of the trans population. While the needs of this group have only recently received attention, global, regional and other technical guidance documents are being developed to address these gaps. Regional blueprints for comprehensive care for trans people in Latin America, the Caribbean, and Asia and the Pacific are now available. These tools  supported by the Pan American Health Organization, World Health Organization, US President's Emergency Plan for AIDS Relief and the United Nations Development Programme, in collaboration with regional trans groups  provide a contextual map, indicating opportunities for interventions in health, HIV, violence, stigma and discrimination, social protection and human rights. Global guidance includes the World Health Organization's Policy Brief: Transgender People and HIV, and the interagency publication, Implementing Comprehensive HIV and STI Programmes with Transgender People. Community empowerment and capacity building are the focus of the new tools for global and regional transgender guidance. The goal is to strengthen and ensure communityled responses to the HIV challenge in trans populations. This article describes the new tools and guidance and considers the steps needed to use them to appropriately support and engage transgender

Putting the t in tools: a roadmap for implementation of new global and regional transgender guidance
PubMed Central
Wolf, R Cameron; Adams, Darrin; Dayton, Robyn; Verster, Annette; Wong, Joe; Romero, Marcela; Mazin, Rafael; Settle, Edmund; Sladden, Tim; Keatley, JoAnne
20160101
Transgender (trans) activists and global health partners have collaborated to develop new tools and guidance for assessing and addressing HIV and other health needs within trans populations. Trans women experience a heavy burden of HIV and other sexually transmitted infections (STIs), high incidence of violence and difficulties accessing genderaffirming services. At the same time, little has been published on trans men's health, HIV issues, needs and experiences. Young trans people are especially marginalized and vulnerable, with few programmes and services specifically tailored to their needs. Transspecific data and guidance are needed to adapt the global response to HIV to meet the needs of the trans population. While the needs of this group have only recently received attention, global, regional and other technical guidance documents are being developed to address these gaps. Regional blueprints for comprehensive care for trans people in Latin America, the Caribbean, and Asia and the Pacific are now available. These tools – supported by the Pan American Health Organization, World Health Organization, US President's Emergency Plan for AIDS Relief and the United Nations Development Programme, in collaboration with regional trans groups – provide a contextual map, indicating opportunities for interventions in health, HIV, violence, stigma and discrimination, social protection and human rights. Global guidance includes the World Health Organization's Policy Brief: Transgender People and HIV, and the interagency publication, Implementing Comprehensive HIV and STI Programmes with Transgender People. Community empowerment and capacity building are the focus of the new tools for global and regional transgender guidance. The goal is to strengthen and ensure communityled responses to the HIV challenge in trans populations. This article describes the new tools and guidance and considers the steps needed to use them to appropriately support and engage transgender

Integration of existing systematic reviews into new reviews: identification of guidance needs
PubMed Central
20140101
Background An exponential increase in the number of systematic reviews published, and constrained resources for new reviews, means that there is an urgent need for guidance on explicitly and transparently integrating existing reviews into new systematic reviews. The objectives of this paper are: 1) to identify areas where existing guidance may be adopted or adapted, and 2) to suggest areas for future guidance development. Methods We searched documents and websites from healthcare focused systematic review organizations to identify and, where available, to summarize relevant guidance on the use of existing systematic reviews. We conducted informational interviews with members of Evidencebased Practice Centers (EPCs) to gather experiences in integrating existing systematic reviews, including common issues and challenges, as well as potential solutions. Results There was consensus among systematic review organizations and the EPCs about some aspects of incorporating existing systematic reviews into new reviews. Current guidance may be used in assessing the relevance of prior reviews and in scanning references of prior reviews to identify studies for a new review. However, areas of challenge remain. Areas in need of guidance include how to synthesize, grade the strength of, and present bodies of evidence composed of primary studies and existing systematic reviews. For instance, empiric evidence is needed regarding how to quality check data abstraction and when and how to use studylevel risk of bias assessments from prior reviews. Conclusions There remain areas of uncertainty for how to integrate existing systematic reviews into new reviews. Methods research and consensus processes among systematic review organizations are needed to develop guidance to address these challenges. PMID:24956937

Using discrete choice experiments to understand preferences in health care.
PubMed
Pfarr, Christian; Schmid, Andreas; Schneider, Udo
20140101
Whenever processes are reconfigured or new products are designed the needs and preferences of patients and consumers have to be considered. Although at times neglected, this becomes more and more relevant in health care settings: Which modes of health care delivery will be accepted? What are the patients' priorities and what is the willingness to pay? To which degree are patients mobile and for which kind of services are they willing to travel? Preferences, however, are difficult to measure, as they are latent constructs. This becomes even more difficult, when no past choices can be analyzed either as the service or the product is yet to be developed or as in the past there has not been free choice for patients. In such cases, preferences cannot be surveyed directly. Asking individuals openly for their attitudes towards certain services and products, the results are likely biased as individuals are not confronted with budget constraints and tradeoffs. For this reason, discrete choice experiments (DCEs) are frequently used to elicit patient preferences. This approach confronts patients with hypothetical scenarios of which only one can be chosen. Over the past few years, this tool to reveal patients' preferences for health care has become very popular in health economics. This contribution aims at introducing the principles of DCEs, highlighting the underlying theory and giving practical guidance for conducting a discrete choice experiment in health economics. Thereby we focus on three major fields of patient demand: designing health insurance, assessing patient utility of new pharmaceuticals and analyzing provider choice. By having a closer look at selected international studies, we discuss the application of this technique for the analysis of the supply and the demand of health care as well as the implications for assessing patient mobility across different health care systems. PMID:24864381

76 FR 61098  Guidance for 1Hour SO2
Federal Register 2010, 2011, 2012, 2013, 2014
20111003
...Notice is hereby given that the EPA has posted its draft non binding guidance titled, ``Guidance for 1Hour SO2 NAAQS SIP Submissions'' on its Web site. The EPA invites public comments on this guidance document during the comment period specified below, and plans to issue an updated version of the guidance after reviewing timely submitted...

Constituent Aspects of Workplace Guidance in Secondary VET
ERIC Educational Resources Information Center
Swager, Robert; Klarus, Ruud; van Merriënboer, Jeroen J. G.; Nieuwenhuis, Loek F. M.
20150101
Purpose: This paper aims to present an integrated model of workplace guidance to enhance awareness of what constitutes good guidance, to improve workplace guidance practices in vocational education and training. Design/methodology/approach: To identify constituent aspects of workplace guidance, a systematic search of Web of Science was conducted,…

Earlier Guidance Opportunities: Priorities for the 1970's.
ERIC Educational Resources Information Center
Nemec, William E., Ed.
"Earlier Guidance Opportunities (EGO): Priorities for the 1970's" was the topic for this Ohio Elementary Guidance Conference. In his keynote address entitled "New Perspectives on the Guidance of Younger Children  Can We Afford to Delay Vocational Guidance?" Dr. George E. Hill used EGO to say, "Education Gives Opportunity,""Ego's Grow on…

Comparison of Fully Numerical PredictorCorrector and Apollo Skip Entry Guidance Algorithms
NASA Astrophysics Data System (ADS)
Brunner, Christopher W.; Lu, Ping
20120901
The dramatic increase in computational power since the Apollo program has enabled the development of numerical predictorcorrector (NPC) entry guidance algorithms that allow onboard accurate determination of a vehicle's trajectory. These algorithms are sufficiently mature to be flown. They are highly adaptive, especially in the face of extreme dispersion and offnominal situations compared with referencetrajectory following algorithms. The performance and reliability of entry guidance are critical to mission success. This paper compares the performance of a recently developed fully numerical predictorcorrector entry guidance (FNPEG) algorithm with that of the Apollo skip entry guidance. Through extensive dispersion testing, it is clearly demonstrated that the Apollo skip entry guidance algorithm would be inadequate in meeting the landing precision requirement for missions with medium (40007000 km) and long (>7000 km) downrange capability requirements under moderate dispersions chiefly due to poor modeling of atmospheric drag. In the presence of large dispersions, a significant number of failures occur even for shortrange missions due to the deviation from planned reference trajectories. The FNPEG algorithm, on the other hand, is able to ensure high landing precision in all cases tested. All factors considered, a strong case is made for adopting fully numerical algorithms for future skip entry missions.

Launch flexibility using NLP guidance and remote wind sensing
NASA Technical Reports Server (NTRS)
Cramer, Evin J.; Bradt, Jerre E.; Hardtla, John W.
19900101
This paper examines the use of lidar wind measurements in the implementation of a guidance strategy for a nonlinear programming (NLP) launch guidance algorithm. The NLP algorithm uses Bspline command function representation for flexibility in the design of the guidance steering commands. Using this algorithm, the guidance system solves a twopoint boundary value problem at each guidance update. The specification of different boundary value problems at each guidance update provides flexibility that can be used in the design of the guidance strategy. The algorithm can use lidar wind measurements for on pad guidance retargeting and for load limiting guidance steering commands. Examples presented in the paper use simulated wind updates to correct wind induced final orbit errors and to adjust the guidance steering commands to limit the product of the dynamic pressure and angleofattack for launch vehicle load alleviation.

The discretetime compensated Kalman filter
NASA Technical Reports Server (NTRS)
Lee, W. H.; Athans, M.
19780101
A suboptimal dynamic compensator to be used in conjunction with the ordinary discrete time Kalman filter was derived. The resultant compensated Kalman Filter has the property that steady state bias estimation errors, resulting from modelling errors, were eliminated.

Running Parallel Discrete Event Simulators on Sierra
SciTech Connect
Barnes, P. D.; Jefferson, D. R.
20151203
In this proposal we consider porting the ROSS/Charm++ simulator and the discrete event models that run under its control so that they run on the Sierra architecture and make efficient use of the Volta GPUs.

Motion of Discrete Interfaces Through Mushy Layers
NASA Astrophysics Data System (ADS)
Braides, Andrea; Solci, Margherita
20160401
We study the geometric motion of sets in the plane derived from the homogenization of discrete ferromagnetic energies with weak inclusions. We show that the discrete sets are composed by a `bulky' part and an external `mushy region' composed only of weak inclusions. The relevant motion is that of the bulky part, which asymptotically obeys to a motion by crystalline mean curvature with a forcing term, due to the energetic contribution of the mushy layers, and pinning effects, due to discreteness. From an analytical standpoint, it is interesting to note that the presence of the mushy layers implies only a weak and not strong convergence of the discrete motions, so that the convergence of the energies does not commute with the evolution. From a mechanical standpoint it is interesting to note the geometrical similarity of some phenomena in the cooling of binary melts.

A discrete control model of PLANT
NASA Technical Reports Server (NTRS)
Mitchell, C. M.
19850101
A model of the PLANT system using the discrete control modeling techniques developed by Miller is described. Discrete control models attempt to represent in a mathematical form how a human operator might decompose a complex system into simpler parts and how the control actions and system configuration are coordinated so that acceptable overall system performance is achieved. Basic questions include knowledge representation, information flow, and decision making in complex systems. The structure of the model is a general hierarchical/heterarchical scheme which structurally accounts for coordination and dynamic focus of attention. Mathematically, the discrete control model is defined in terms of a network of finite state systems. Specifically, the discrete control model accounts for how specific control actions are selected from information about the controlled system, the environment, and the context of the situation. The objective is to provide a plausible and empirically testable accounting and, if possible, explanation of control behavior.

Motion of Discrete Interfaces Through Mushy Layers
NASA Astrophysics Data System (ADS)
Braides, Andrea; Solci, Margherita
20160801
We study the geometric motion of sets in the plane derived from the homogenization of discrete ferromagnetic energies with weak inclusions. We show that the discrete sets are composed by a `bulky' part and an external `mushy region' composed only of weak inclusions. The relevant motion is that of the bulky part, which asymptotically obeys to a motion by crystalline mean curvature with a forcing term, due to the energetic contribution of the mushy layers, and pinning effects, due to discreteness. From an analytical standpoint, it is interesting to note that the presence of the mushy layers implies only a weak and not strong convergence of the discrete motions, so that the convergence of the energies does not commute with the evolution. From a mechanical standpoint it is interesting to note the geometrical similarity of some phenomena in the cooling of binary melts.

Discrete Element Modeling of Drop Tests
NASA Astrophysics Data System (ADS)
Wang, Yuannian; Tonon, Fulvio
20120901
A discrete element code with impact model has been developed and calibrated to simulate the dynamic behavior of rock materials, with special regard to rock fragmentation upon impact during rockfall analysis. The paper summarizes the discrete element code, the calibration algorithms developed to identify the model microparameters, and the impact model. Experimental work on drop tests is then used to validate the code on modeling impact fragmentation. It has been found that the developed discrete element code and impact model can reasonably simulate rock fragmentation in drop tests. The use of the discrete element code and impact model can provide good reference results in evaluating impact fragmentation in rockfall analysis.

Comparing the Discrete and Continuous Logistic Models
ERIC Educational Resources Information Center
Gordon, Sheldon P.
20080101
The solutions of the discrete logistic growth model based on a difference equation and the continuous logistic growth model based on a differential equation are compared and contrasted. The investigation is conducted using a dynamic interactive spreadsheet. (Contains 5 figures.)

Reducing Neuronal Networks to Discrete Dynamics
PubMed Central
Terman, David; Ahn, Sungwoo; Wang, Xueying; Just, Winfried
20080101
We consider a general class of purely inhibitory and excitatoryinhibitory neuronal networks, with a general class of network architectures, and characterize the complex firing patterns that emerge. Our strategy for studying these networks is to first reduce them to a discrete model. In the discrete model, each neuron is represented as a finite number of states and there are rules for how a neuron transitions from one state to another. In this paper, we rigorously demonstrate that the continuous neuronal model can be reduced to the discrete model if the intrinsic and synaptic properties of the cells are chosen appropriately. In a companion paper [1], we analyze the discrete model. PMID:18443649

Dynamic discretization method for solving Kepler's equation
NASA Astrophysics Data System (ADS)
Feinstein, Scott A.; McLaughlin, Craig A.
20060901
Kepler’s equation needs to be solved many times for a variety of problems in Celestial Mechanics. Therefore, computing the solution to Kepler’s equation in an efficient manner is of great importance to that community. There are some historical and many modern methods that address this problem. Of the methods known to the authors, Fukushima’s discretization technique performs the best. By taking more of a system approach and combining the use of discretization with the standard computer science technique known as dynamic programming, we were able to achieve even better performance than Fukushima. We begin by defining Kepler’s equation for the elliptical case and describe existing solution methods. We then present our dynamic discretization method and show the results of a comparative analysis. This analysis will demonstrate that, for the conditions of our tests, dynamic discretization performs the best.

78 FR 37231  Guidance for Industry; Guidance on Abbreviated New Drug Applications: Stability Testing of Drug...
Federal Register 2010, 2011, 2012, 2013, 2014
20130620
...The Food and Drug Administration (FDA or Agency) is announcing the availability of a guidance entitled ``ANDAs: Stability Testing of Drug Substances and Products.'' FDA is recommending generic drug manufacturers follow the stability testing recommendations in the International Conference on Harmonisation (ICH) guidances Q1A (R2) through Q1E. The use of these ICH recommendations will......

Raising the Profile of Career Guidance: Educational and Vocational Guidance Practitioner
ERIC Educational Resources Information Center
Hiebert, Bryan
20090101
In 2007 the International Association for Educational and Vocational Guidance (IAEVG) launched the Educational and Vocational Guidance Practitioner credential (EVGP) as one means of formally acknowledging the knowledge, skills, and personal attributes that practitioners need in order to provide quality career development services to clients. This…

FACILITATING LEARNING AND INDIVIDUAL DEVELOPMENT, TOWARD A THEORY FOR ELEMENTARY GUIDANCE. MINNESOTA GUIDANCE SERIES.
ERIC Educational Resources Information Center
GRAMS, ARMIN
A THEORY UPON WHICH ELEMENTARY GUIDANCE PROGRAMS CAN BE SOUNDLY DESIGNED IS PRESENTED. A MAJOR THEME IS THAT PSYCHOLOGICAL WELLBEING OR GOOD ADJUSTMENT IS RELATED TO LEARNED, INDIVIDUAL COMPETENCIES SUCH AS COMMUNICATION AND INTERACTION IN DEPTH WITH OTHERS. THE APPROPRIATE CONCERN OF GUIDANCE THEN BECOMES TO FOSTER THESE COMPETENCIES, THUS…

Radiation Protection Guidance for Diagnostic and Interventional XRay Procedures; Federal Guidance Report No. 14
EPA Science Inventory
Federal Guidance Report No. 14 provides federal facilities that use diagnostic and interventional xray equipment with updated recommendations for keeping doses as low as reasonably achievable without compromising the quality of patient care, This guidance is an update of Federal...

Eigenforms, Discrete Processes and Quantum Processes
NASA Astrophysics Data System (ADS)
Kauffman, Louis H.
20120501
This essay is a discussion of the concept of eigenform, due to Heinz von Foerster, and its relationship with discrete physics and quantum mechanics. We interpret the square root of minus one as a simple oscillatory process  a clock, and as an eigenform. By taking a generalization of this identification of i as a clock and eigenform, we show how quantum mechanics emerges from discrete physics.

Separable twodimensional discrete Hartley transform
NASA Technical Reports Server (NTRS)
Watson, Andrew B.; Poirson, Allen
19860101
Bracewell has proposed the Discrete Hartley Transform (DHT) as a substitute for the Discrete Fourier Transform (DFT), particularly as a means of convolution. Here, it is shown that the most natural extension of the DHT to two dimensions fails to be separate in the two dimensions, and is therefore inefficient. An alternative separable form is considered, corresponding convolution theorem is derived. That the DHT is unlikely to provide faster convolution than the DFT is also discussed.

`t Hooft anomaly matching for discrete symmetries
SciTech Connect
Csaki, C.; Murayama, Hitoshi 
19980501
The authors show how to extend the `t Hooft anomaly matching conditions to discrete symmetries. They check these discrete anomally matching conditions on several proposed lowenergy spectra of certain strongly interacting gauge theories. The excluded examples include the proposed chirally symmetric vacuum of pure N = 1 supersymmetric yangMills theories, certain nonsupersymmetric confining theories and some selfdual N = 1 supersymmetric theories based on exceptional groups.

Terminal Dynamics Approach to Discrete Event Systems
NASA Technical Reports Server (NTRS)
Zak, Michail; Meyers, Ronald
19950101
This paper presents and discusses a mathematical formalism for simulation of discrete event dynamic (DED)a special type of 'manmade' systems to serve specific purposes of information processing. The main objective of this work is to demonstrate that the mathematical formalism for DED can be based upon a terminal model of Newtonian dynamics which allows one to relax Lipschitz conditions at some discrete points.!.

Discrete wavelet analysis of power system transients
SciTech Connect
Wilkinson, W.A.; Cox, M.D.
19961101
Wavelet analysis is a new method for studying power system transients. Through wavelet analysis, transients are decomposed into a series of wavelet components, each of which is a timedomain signal that covers a specific octave frequency band. This paper presents the basic ideas of discrete wavelet analysis. A variety of actual and simulated transient signals are then analyzed using the discrete wavelet transform that help demonstrate the power of wavelet analysis.

Unstructured Adaptive Meshes: Bad for Your Memory?
NASA Technical Reports Server (NTRS)
Biswas, Rupak; Feng, HuiYu; VanderWijngaart, Rob
20030101
This viewgraph presentation explores the need for a NASA Advanced Supercomputing (NAS) parallel benchmark for problems with irregular dynamical memory access. This benchmark is important and necessary because: 1) Problems with localized error source benefit from adaptive nonuniform meshes; 2) Certain machines perform poorly on such problems; 3) Parallel implementation may provide further performance improvement but is difficult. Some examples of problems which use irregular dynamical memory access include: 1) Heat transfer problem; 2) Heat source term; 3) Spectral element method; 4) Base functions; 5) Elemental discrete equations; 6) Global discrete equations. Nonconforming Mesh and Mortar Element Method are covered in greater detail in this presentation.

Guidance and control, 1993; Annual Rocky Mountain Guidance and Control Conference, 16th, Keystone, CO, Feb. 610, 1993
NASA Technical Reports Server (NTRS)
Culp, Robert D. (Editor); Bickley, George (Editor)
19930101
Papers from the sixteenth annual American Astronautical Society Rocky Mountain Guidance and Control Conference are presented. The topics covered include the following: advances in guidance, navigation, and control; control system videos; guidance, navigation and control embedded flight control systems; recent experiences; guidance and control storyboard displays; and applications of modern control, featuring the Hubble Space Telescope (HST) performance enhancement study.

Measuring Integrated Socioemotional Guidance at School: Factor Structure and Reliability of the Socioemotional Guidance Questionnaire (SEGQ)
ERIC Educational Resources Information Center
Jacobs, Karen; Struyf, Elke
20130101
Socioemotional guidance of students has recently become an integral part of education, however no instrument exists to measure integrated socioemotional guidance. This study therefore examines the factor structure and reliability of the Socioemotional Guidance Questionnaire. Psychometric properties of the Socioemotional Guidance Questionnaire and…

Safety of magnetic fusion facilities: Guidance
SciTech Connect
19960501
This document provides guidance for the implementation of the requirements identified in DOESTD600296, Safety of Magnetic Fusion Facilities: Requirements. This guidance is intended for the managers, designers, operators, and other personnel with safety responsibilities for facilities designated as magnetic fusion facilities. While the requirements in DOESTD600296 are generally applicable to a wide range of fusion facilities, this Standard, DOESTD600396, is concerned mainly with the implementation of those requirements in large facilities such as the International Thermonuclear Experimental Reactor (ITER). Using a riskbased prioritization, the concepts presented here may also be applied to other magnetic fusion facilities. This Standard is oriented toward regulation in the Department of Energy (DOE) environment as opposed to regulation by other regulatory agencies. As the need for guidance involving other types of fusion facilities or other regulatory environments emerges, additional guidance volumes should be prepared. The concepts, processes, and recommendations set forth here are for guidance only. They will contribute to safety at magnetic fusion facilities.

Fine Guidance Sensing for Coronagraphic Observatories
NASA Technical Reports Server (NTRS)
Brugarolas, Paul; Alexander, James W.; Trauger, John T.; Moody, Dwight C.
20110101
Three options have been developed for Fine Guidance Sensing (FGS) for coronagraphic observatories using a Fine Guidance Camera within a coronagraphic instrument. Coronagraphic observatories require very fine precision pointing in order to image faint objects at very small distances from a target star. The Fine Guidance Camera measures the direction to the target star. The first option, referred to as Spot, was to collect all of the light reflected from a coronagraph occulter onto a focal plane, producing an Airytype point spread function (PSF). This would allow almost all of the starlight from the central star to be used for centroiding. The second approach, referred to as Punctured Disk, collects the light that bypasses a central obscuration, producing a PSF with a punctured central disk. The final approach, referred to as Lyot, collects light after passing through the occulter at the Lyot stop. The study includes generation of representative images for each option by the science team, followed by an engineering evaluation of a centroiding or a photometric algorithm for each option. After the alignment of the coronagraph to the fine guidance system, a "nulling" point on the FGS focal point is determined by calibration. This alignment is implemented by a fine alignment mechanism that is part of the fine guidance camera selection mirror. If the star images meet the modeling assumptions, and the star "centroid" can be driven to that nulling point, the contrast for the coronagraph will be maximized.

Method for continuous guidance of endoscopy
NASA Astrophysics Data System (ADS)
Merritt, Scott A.; Rai, Lav; Gibbs, Jason D.; Yu, KunChang; Higgins, William E.
20070301
Previous research has indicated that use of guidance systems during endoscopy can improve the performance and decrease the skill variation of physicians. Current guidance systems, however, rely on computationally intensive registration techniques or costly and errorprone electromagnetic (E/M) registration techniques, neither of which fit seamlessly into the clinical workflow. We have previously proposed a realtime imagebased registration technique that addresses both of these problems. We now propose a systemlevel approach that incorporates this technique into a complete paradigm for realtime imagebased guidance in order to provide a physician with continuouslyupdated navigational and guidance information. At the core of the system is a novel strategy for guidance of endoscopy. Additional elements such as global surface rendering, local crosssectional views, and pertinent distances are also incorporated into the system to provide additional utility to the physician. Phantom results were generated using bronchoscopy performed on a rapid prototype model of a human tracheobronchial airway tree. The system has also been tested in ongoing live human tests. Thus far, ten such tests, focused on bronchoscopic intervention of pulmonary patients, have been run successfully.

Constrained reconstructions for 4D intervention guidance
NASA Astrophysics Data System (ADS)
Kuntz, J.; Flach, B.; Kueres, R.; Semmler, W.; Kachelrieß, M.; Bartling, S.
20130501
Imageguided interventions are an increasingly important part of clinical minimally invasive procedures. However, up to now they cannot be performed under 4D (3D + time) guidance due to the exceedingly high xray dose. In this work we investigate the applicability of compressed sensing reconstructions for highly undersampled CT datasets combined with the incorporation of prior images in order to yield low dose 4D intervention guidance. We present a new reconstruction scheme prior image dynamic interventional CT (PrIDICT) that accounts for specific image features in intervention guidance and compare it to PICCS and ASDPOCS. The optimal parameters for the dose per projection and the numbers of projections per reconstruction are determined in phantom simulations and measurements. In vivo experiments in six pigs are performed in a conebeam CT; measured doses are compared to current goldstandard intervention guidance represented by a clinical fluoroscopy system. Phantom studies show maximum image quality for identical overall doses in the range of 14 to 21 projections per reconstruction. In vivo studies reveal that interventional materials can be followed in 4D visualization and that PrIDICT, compared to PICCS and ASDPOCS, shows superior reconstruction results and fewer artifacts in the periphery with dose in the order of biplane fluoroscopy. These results suggest that 4D intervention guidance can be realized with today’s flat detector and gantry systems using the herein presented reconstruction scheme.

Light Adaptation in the Ventral Photoreceptor of Limulus
PubMed Central
Srebro, Richard; Behbehani, Michael
19740101
Light adaptation in both the ventral photoreceptor and the lateral eye photoreceptor is a complex process consisting of at least two phases. One phase, which we call the rapid phase of adaptation, occurs whenever there is temporal overlap of the discrete waves that compose a light response. The recovery from the rapid phase of adaptation follows an exponential timecourse with a time constant of approximately 75 ms at 21°C. The rapid phase of adaptation occurs at light intensities barely above discrete wave threshold as well as at substantially higher light intensities with the same recovery timecourse at all intensities. It occurs in voltageclamped and unclamped photoreceptors. The kinetics of the rapid phase of adaptation is closely correlated to the photocurrent which appears to initiate it after a short delay. The rapid phase of adaptation is probably identical to what is called the "adapting bump" process. At light intensities greater than about 10 times discrete wave threshold another phase of light adaptation occurs. It develops slowly over a period of ½ s or so, and decays even more slowly over a period of several seconds. It is graded with light intensity and occurs in both voltageclamped and unclamped photoreceptors. We call this the slow phase of light adaptation. PMID:4846765

Axioms of adaptivity
PubMed Central
Carstensen, C.; Feischl, M.; Page, M.; Praetorius, D.
20140101
This paper aims first at a simultaneous axiomatic presentation of the proof of optimal convergence rates for adaptive finite element methods and second at some refinements of particular questions like the avoidance of (discrete) lower bounds, inexact solvers, inhomogeneous boundary data, or the use of equivalent error estimators. Solely four axioms guarantee the optimality in terms of the error estimators. Compared to the state of the art in the temporary literature, the improvements of this article can be summarized as follows: First, a general framework is presented which covers the existing literature on optimality of adaptive schemes. The abstract analysis covers linear as well as nonlinear problems and is independent of the underlying finite element or boundary element method. Second, efficiency of the error estimator is neither needed to prove convergence nor quasioptimal convergence behavior of the error estimator. In this paper, efficiency exclusively characterizes the approximation classes involved in terms of the bestapproximation error and data resolution and so the upper bound on the optimal marking parameters does not depend on the efficiency constant. Third, some general quasiGalerkin orthogonality is not only sufficient, but also necessary for the Rlinear convergence of the error estimator, which is a fundamental ingredient in the current quasioptimality analysis due to Stevenson 2007. Finally, the general analysis allows for equivalent error estimators and inexact solvers as well as different nonhomogeneous and mixed boundary conditions. PMID:25983390

Discrete exterior calculus discretization of incompressible NavierStokes equations over surface simplicial meshes
NASA Astrophysics Data System (ADS)
Mohamed, Mamdouh S.; Hirani, Anil N.; Samtaney, Ravi
20160501
A conservative discretization of incompressible NavierStokes equations is developed based on discrete exterior calculus (DEC). A distinguishing feature of our method is the use of an algebraic discretization of the interior product operator and a combinatorial discretization of the wedge product. The governing equations are first rewritten using the exterior calculus notation, replacing vector calculus differential operators by the exterior derivative, Hodge star and wedge product operators. The discretization is then carried out by substituting with the corresponding discrete operators based on the DEC framework. Numerical experiments for flows over surfaces reveal a second order accuracy for the developed scheme when using structuredtriangular meshes, and first order accuracy for otherwise unstructured meshes. By construction, the method is conservative in that both mass and vorticity are conserved up to machine precision. The relative error in kinetic energy for inviscid flow test cases converges in a second order fashion with both the mesh size and the time step.

Quantum walks and discrete gauge theories
NASA Astrophysics Data System (ADS)
Arnault, Pablo; Debbasch, Fabrice
20160501
A particular example is produced to prove that quantum walks can be used to simulate fullfledged discrete gauge theories. A family of twodimensional walks is introduced and its continuous limit is shown to coincide with the dynamics of a Dirac fermion coupled to arbitrary electromagnetic fields. The electromagnetic interpretation is extended beyond the continuous limit by proving that these discretetime quantum walks (DTQWs) exhibit an exact discrete local U(1) gauge invariance and possess a discrete gaugeinvariant conserved current. A discrete gaugeinvariant electromagnetic field is also constructed and that field is coupled to the conserved current by a discrete generalization of Maxwell equations. The dynamics of the DTQWs under crossed electric and magnetic fields is finally explored outside the continuous limit by numerical simulations. Bloch oscillations and the socalled E ×B drift are recovered in the weakfield limit. Localization is observed for some values of the gauge fields.

Discrete differential geometry: The nonplanar quadrilateral mesh
NASA Astrophysics Data System (ADS)
Twining, Carole J.; Marsland, Stephen
20120601
We consider the problem of constructing a discrete differential geometry defined on nonplanar quadrilateral meshes. Physical models on discrete nonflat spaces are of inherent interest, as well as being used in applications such as computation for electromagnetism, fluid mechanics, and image analysis. However, the majority of analysis has focused on triangulated meshes. We consider two approaches: discretizing the tensor calculus, and a discrete mesh version of differential forms. While these two approaches are equivalent in the continuum, we show that this is not true in the discrete case. Nevertheless, we show that it is possible to construct mesh versions of the LeviCivita connection (and hence the tensorial covariant derivative and the associated covariant exterior derivative), the torsion, and the curvature. We show how discrete analogs of the usual vector integral theorems are constructed in such a way that the appropriate conservation laws hold exactly on the mesh, rather than only as approximations to the continuum limit. We demonstrate the success of our method by constructing a mesh version of classical electromagnetism and discuss how our formalism could be used to deal with other physical models, such as fluids.

Discrete differential geometry: the nonplanar quadrilateral mesh.
PubMed
Twining, Carole J; Marsland, Stephen
20120601
We consider the problem of constructing a discrete differential geometry defined on nonplanar quadrilateral meshes. Physical models on discrete nonflat spaces are of inherent interest, as well as being used in applications such as computation for electromagnetism, fluid mechanics, and image analysis. However, the majority of analysis has focused on triangulated meshes. We consider two approaches: discretizing the tensor calculus, and a discrete mesh version of differential forms. While these two approaches are equivalent in the continuum, we show that this is not true in the discrete case. Nevertheless, we show that it is possible to construct mesh versions of the LeviCivita connection (and hence the tensorial covariant derivative and the associated covariant exterior derivative), the torsion, and the curvature. We show how discrete analogs of the usual vector integral theorems are constructed in such a way that the appropriate conservation laws hold exactly on the mesh, rather than only as approximations to the continuum limit. We demonstrate the success of our method by constructing a mesh version of classical electromagnetism and discuss how our formalism could be used to deal with other physical models, such as fluids. PMID:23005244

Interaction of the guidance molecule Slit with cellular receptors.
PubMed
Hohenester, E; Hussain, S; Howitt, J A
20060601
Slits are large secreted glycoproteins characterized by an unusual tandem of four LRR (leucinerich repeat) domains in their Nterminal half. Slit proteins were initially described as repulsive guidance cues in neural development, but it has become clear that they have additional important functions, for instance in the vasculature and immune system. Genetic studies have identified two types of cellular receptors for Slits: Robos (Roundabout) and the HS (heparan sulphate) proteoglycan syndecan. The intracellular signalling cascade downstream of Robo activation is slowly being elucidated, but the mechanism of transmembrane signalling by Robo has remained obscure. No active signalling role for syndecan has yet been demonstrated. SlitHS interactions may be important for shaping the presumed Slit gradient or presenting Slit at its target cell surface. Recent studies have mapped the binding sites for Robos and HS/heparin to discrete Slit domains. Robos bind to the second LRR domain of Slit, whereas HS/heparin binds with very high affinity to the Cterminal portion of Slit. Slit activity is likely to be modulated by physiological proteolytic cleavage in the region separating the Robo and HS/heparinbinding sites. PMID:16709176

Software Safety Analysis of a Flight Guidance System
NASA Technical Reports Server (NTRS)
Butler, Ricky W. (Technical Monitor); Tribble, Alan C.; Miller, Steven P.; Lempia, David L.
20040101
This document summarizes the safety analysis performed on a Flight Guidance System (FGS) requirements model. In particular, the safety properties desired of the FGS model are identified and the presence of the safety properties in the model is formally verified. Chapter 1 provides an introduction to the entire project, while Chapter 2 gives a brief overview of the problem domain, the nature of accidents, model based development, and the fourvariable model. Chapter 3 outlines the approach. Chapter 4 presents the results of the traditional safety analysis techniques and illustrates how the hazardous conditions associated with the system trace into specific safety properties. Chapter 5 presents the results of the formal methods analysis technique model checking that was used to verify the presence of the safety properties in the requirements model. Finally, Chapter 6 summarizes the main conclusions of the study, first and foremost that model checking is a very effective verification technique to use on discrete models with reasonable state spaces. Additional supporting details are provided in the appendices.

HUMAN FACTORS GUIDANCE FOR CONTROL ROOM EVALUATION
SciTech Connect
OHARA,J.; BROWN,W.; STUBLER,W.; HIGGINS,J.; WACHTEL,J.; PERSENSKY,J.J.
20000730
The HumanSystem Interface Design Review Guideline (NUREG0700, Revision 1) was developed by the US Nuclear Regulatory Commission (NRC) to provide human factors guidance as a basis for the review of advanced humansystem interface technologies. The guidance consists of three components: design review procedures, human factors engineering guidelines, and a software application to provide design review support called the ``Design Review Guideline.'' Since it was published in June 1996, Rev. 1 to NUREG0700 has been used successfully by NRC staff, contractors and nuclear industry organizations, as well as by interested organizations outside the nuclear industry. The NRC has committed to the periodic update and improvement of the guidance to ensure that it remains a stateoftheart design evaluation tool in the face of emerging and rapidly changing technology. This paper addresses the current research to update of NUREG0700 based on the substantial work that has taken place since the publication of Revision 1.

VTOL shipboard letdown guidance system analysis
NASA Technical Reports Server (NTRS)
Phatak, A. V.; Karmali, M. S.
19830101
Alternative letdown guidance strategies are examined for landing of a VTOL aircraft onboard a small aviation ship under adverse environmental conditions. Off line computer simulation of shipboard landing task is utilized for assessing the relative merits of the proposed guidance schemes. The touchdown performance of a nominal constant rate of descent (CROD) letdown strategy serves as a benchmark for ranking the performance of the alternative letdown schemes. Analysis of ship motion time histories indicates the existence of an alternating sequence of quiescent and rough motions called lulls and swells. A real time algorithms lull/swell classification based upon ship motion pattern features is developed. The classification algorithm is used to command a go/no go signal to indicate the initiation and termination of an acceptable landing window. Simulation results show that such a go/no go pattern based letdown guidance strategy improves touchdown performance.

Human Genetic Disorders of Axon Guidance
PubMed Central
Engle, Elizabeth C.
20100101
This article reviews symptoms and signs of aberrant axon connectivity in humans, and summarizes major human genetic disorders that result, or have been proposed to result, from defective axon guidance. These include corpus callosum agenesis, L1 syndrome, Joubert syndrome and related disorders, horizontal gaze palsy with progressive scoliosis, Kallmann syndrome, albinism, congenital fibrosis of the extraocular muscles type 1, Duane retraction syndrome, and pontine tegmental cap dysplasia. Genes mutated in these disorders can encode axon growth cone ligands and receptors, downstream signaling molecules, and axon transport motors, as well as proteins without currently recognized roles in axon guidance. Advances in neuroimaging and genetic techniques have the potential to rapidly expand this field, and it is feasible that axon guidance disorders will soon be recognized as a new and significant category of human neurodevelopmental disorders. PMID:20300212

Calcium and the control of discrete wave latency in the ventral photoreceptor of Limulus.
PubMed Central
Martinez, J M; Srebro, R
19760101
1. Discrete, transient depolarization (discrete waves) of the ventral photoreceptor of the horseshoe crab, Limulus, occur spontaneously in the dark adapted photoreceptor and are also evoked by light. They form the basic events which comprise the receptor potential. A brief, low energy flash of light evokes variable numbers of discrete waves which have variable latencies. Evidence suggesting that discrete wave latency reflects the kinetics of the chemical reactions of phototransduction is reviewed. 2. The concentration of extracellular Ca influences both the average discrete wave latency and its variability. Lowering extracellular Ca prolongs the latency and increases its variability. Increasing extracellular Ca has the opposite effect. 3. Changes in discrete wave latency caused by changes in extracellular Ca require 1015 min to become fully manifest, whereas when the concentration of extracellular K is increased the photoreceptor achieves a steadystate depolarization in 1015 sec. 4. Iontophoresis of the Cachelating agent EGTA into the photoreceptor increases both the average discrete wave latency and its variability. Iontophoresis of CaEGTA mixtures may either increase or decrease discrete wave latency and its variability depending upon the proportion of Ca mixed with EGTA. 5. It is suggested that the concentration of intracellular rather than extracellular ionized Ca is the prime factor indicating discrete wave latency. The effects of changing extracellular Ca can be explained if the photoreceptor is permeable to Ca in the dark and if it maintains a low intracellular Ca concentration by virtue of active metabolic processes (a pumpleak system). 6. Lowering the temperature of the photoreceptor also has the dual effect of increasing discrete wave latency and its variability. However, effects of lowering temperature and Ca simultaneously are greater than the sum of the two effects in individually. This suggests that Ca may be a reactant in the chemical process

Solving UpwindBiased Discretizations: DefectCorrection Iterations
NASA Technical Reports Server (NTRS)
Diskin, Boris; Thomas, James L.
19990101
This paper considers defectcorrection solvers for a second order upwindbiased discretization of the 2D convection equation. The following important features are reported: (1) The asymptotic convergence rate is about 0.5 per defectcorrection iteration. (2) If the operators involved in defectcorrection iterations have different approximation order, then the initial convergence rates may be very slow. The number of iterations required to get into the asymptotic convergence regime might grow on fine grids as a negative power of h. In the case of a second order target operator and a first order driver operator, this number of iterations is roughly proportional to h1/3. (3) If both the operators have the second approximation order, the defectcorrection solver demonstrates the asymptotic convergence rate after three iterations at most. The same three iterations are required to converge algebraic error below the truncation error level. A novel comprehensive halfspace Fourier mode analysis (which, by the way, can take into account the influence of discretized outflow boundary conditions as well) for the defectcorrection method is developed. This analysis explains many phenomena observed in solving nonelliptic equations and provides a close prediction of the actual solution behavior. It predicts the convergence rate for each iteration and the asymptotic convergence rate. As a result of this analysis, a new very efficient adaptive multigrid algorithm solving the discrete problem to within a given accuracy is proposed. Numerical simulations confirm the accuracy of the analysis and the efficiency of the proposed algorithm. The results of the numerical tests are reported.

A comparison of errorcorrection procedures on skill acquisition during discretetrial instruction.
PubMed
Carroll, Regina A; Joachim, Brad T; St Peter, Claire C; Robinson, Nicole
20150101
Previous research supports the use of a variety of errorcorrection procedures to facilitate skill acquisition during discretetrial instruction. We used an adapted alternating treatments design to compare the effects of 4 commonly used errorcorrection procedures on skill acquisition for 2 children with attention deficit hyperactivity disorder and 3 children with autism spectrum disorder. For all participants, multiple errorcorrection procedures were effective; however, 1 or 2 specific errorcorrection procedures led to more efficient skill acquisition for each individual. These results highlight the importance of evaluating the effectiveness and efficiency of errorcorrection procedures for individual learners during discretetrial instruction. We discuss the use of discretetrial instruction with different populations, implications for using multiple measures of procedural efficiency, and several areas for future research. PMID:25913105

Systematic generation of nonlinear discretized dynamic equilibrium equations of spinning cantilevers
NASA Technical Reports Server (NTRS)
ElEssawi, M.; Utku, S.; Salama, M.
19820101
General nonlinear discretized governing equations of motion of spinning elastic solids and structures are adjusted for the case of a spinning cantilever with initial geometric imperfections. Consideration is given to second degree nonlinearities in the straindisplacement and velocitydisplacement relationships. Parameters of the discretization are developed to include the type and number of the coordinate functions used in the admissible trial solution in order to unify the discretization approaches associated with stationarity principles. The coordinate functions comprise both sets of continuous and piecewise continuous functions employed in the RayleighRitz and the finite element methods, respectively. Coefficient matrices are provided which contain the energy density expressions and which are adaptable to computer programming.

A BellCurved Based Algorithm for Mixed Continuous and Discrete Structural Optimization
NASA Technical Reports Server (NTRS)
Kincaid, Rex K.; Weber, Michael; SobieszczanskiSobieski, Jaroslaw
20010101
An evolutionary based strategy utilizing two normal distributions to generate children is developed to solve mixed integer nonlinear programming problems. This BellCurve Based (BCB) evolutionary algorithm is similar in spirit to (mu + mu) evolutionary strategies and evolutionary programs but with fewer parameters to adjust and no mechanism for self adaptation. First, a new version of BCB to solve purely discrete optimization problems is described and its performance tested against a tabu search code for an actuator placement problem. Next, the performance of a combined version of discrete and continuous BCB is tested on 2dimensional shape problems and on a minimum weight hub design problem. In the latter case the discrete portion is the choice of the underlying beam shape (I, triangular, circular, rectangular, or U).

On the Dynamics of Some Discretizations of ConvectionDiffusion Equations
NASA Technical Reports Server (NTRS)
Sweby, Peter K.; Yee, H. C.; Rai, Man Mohan (Technical Monitor)
19950101
Numerical discretizations of differential equations which model physical processes can possess dynamics quite different from that of the equations themselves. Recently the emphasis has been on the the dynamics of numerical discretizations for Ordinary Differential Equations (ODEs). For Partial Differential Equations (PDEs) using a method of lines approach the situation is more complex. First, the spatial discretisation may introduce dynamics not present in the original equations; second, the solution of the resulting system of ODEs is open to the modified dynamics of the ODE solver used. These two effects may interact in a complex manner. In this talk we present some results of our recent work on the dynamics of discretizations of convectiondiffusion equations, including those produced using Total Variation Diminishing (TVD) schemes and adaptive grid techniques. A more general overview of the area may be found on our accompanying poster presentation.

[Guidance for education on medicines in school].
PubMed
Kito, Hideaki
20130101
To promote the education on medicines in school, guidance is, as a rule, to be given in the health education of the Subject, "Health and Physical Education" indicated as a curriculum standard in lower and upper secondary school, and in the health guidance, which carry out in Special Activities and Integrated Studies, etc. Guidance is mainly carried by the teacher for health and physical in health education and school nurse teacher (yogo teacher) in health guidance. In health education we have only limited school hours, and generally use the text book. Some teachers feel resistance to teach medicines because of needs on the special knowledge, however teachers should deal with medicines based on curriculum standard. School pharmacist is a member of school, and has a special knowledge for medicines, and he/she can support teachers as a provider of teaching materials, an adviser, and for a guest teacher. It is important for school pharmacist to understand the contents indicated in curriculum standard and to use glossary to be able to understand for children. In the guidance of health, it is not necessary to teach based on curriculum standard, and it can deal with advanced contents on medicines. However it is important to understand for children what are appropriate contents according to the development stage. To use the packages and instructions for medicines provided at home are good materials for children to have interest the medicines in their guidance. The objectives of education on medicines enable children to cultivate practical abilities for the maintenance and improvement of health. PMID:24292178

Adaptive Development
NASA Technical Reports Server (NTRS)
20050101
The goal of this research is to develop and demonstrate innovative adaptive seal technologies that can lead to dramatic improvements in engine performance, life, range, and emissions, and enhance operability for next generation gas turbine engines. This work is concentrated on the development of selfadaptive clearance control systems for gas turbine engines. Researchers have targeted the highpressure turbine (HPT) blade tip seal location for following reasons: Current active clearance control (ACC) systems (e.g., thermal casecooling schemes) cannot respond to blade tip clearance changes due to mechanical, thermal, and aerodynamic loads. As such they are prone to wear due to the required tight running clearances during operation. Blade tip seal wear (increased clearances) reduces engine efficiency, performance, and service life. Adaptive sealing technology research has inherent impact on all envisioned 21st century propulsion systems (e.g. distributed vectored, hybrid and electric drive propulsion concepts).

Overcoming consumer inertia to dietary guidance.
PubMed
Webb, Densie; ByrdBredbenner, Carol
20150701
Despite 35 y of dietary guidance, there has been no substantial shift in consumer compliance. Consumers report that they seek information on nutrition and healthy eating, but most are not paying attention to dietary recommendations. For guidance to be effective, it must be realistic. Even with increasingly detailed nutrition information and evidence that diet affects health outcomes, convenience and taste remain the strongest determinants of food choices. It is up to health educators to clear up confusion and give consumers control with nutrition messages that are realistic, positive, easy to understand, and actionable without an expectation that consumers will surrender foods they love. PMID:26178023

Development of mining guidance and control systems
NASA Technical Reports Server (NTRS)
19790101
New fundamental interface sensor concepts were identified and investigated including tabulation of the physical and performance characteristics of two new interface detector concepts:  natural background radiation and magnetic spin resonance. Studies of guidance and control techniques for the longwall miner identified three basic systems for use in automated/remote controlled longwall mining. The following projects were initiated: system study which will more completely define the longwall guidance and control system design concepts; integration of the various control functions (vertical, yaw, and roll); and hardware technical requirements.

Virtual Ultrasound Guidance for Inexperienced Operators
NASA Technical Reports Server (NTRS)
Caine, Timothy; Martin, David
20120101
Medical ultrasound or echocardiographic studies are highly operatordependent and generally require lengthy training and internship to perfect. To obtain quality echocardiographic images in remote environments, such as onorbit, remote guidance of studies has been employed. This technique involves minimal training for the user, coupled with remote guidance from an expert. When realtime communication or expert guidance is not available, a more autonomous system of guiding an inexperienced operator through an ultrasound study is needed. One example would be missions beyond low Earth orbit in which the time delay inherent with communication will make remote guidance impractical. The Virtual Ultrasound Guidance system is a combination of hardware and software. The hardware portion includes, but is not limited to, video glasses that allow handsfree, fullscreen viewing. The glasses also allow the operator a substantial field of view below the glasses to view and operate the ultrasound system. The software is a comprehensive video program designed to guide an inexperienced operator through a detailed ultrasound or echocardiographic study without extensive training or guidance from the ground. The program contains a detailed description using video and audio to demonstrate equipment controls, ergonomics of scanning, study protocol, and scanning guidance, including recovery from suboptimal images. The components used in the initial validation of the system include an Apple iPod Classic thirdgeneration as the video source, and Myvue video glasses. Initially, the program prompts the operator to powerup the ultrasound and position the patient. The operator would put on the video glasses and attach them to the video source. After turning on both devices and the ultrasound system, the audiovideo guidance would then instruct on patient positioning and scanning techniques. A detailed scanning protocol follows with descriptions and reference video of each view along with

Overcoming Consumer Inertia to Dietary Guidance12
PubMed Central
Webb, Densie; ByrdBredbenner, Carol
20150101
Despite 35 y of dietary guidance, there has been no substantial shift in consumer compliance. Consumers report that they seek information on nutrition and healthy eating, but most are not paying attention to dietary recommendations. For guidance to be effective, it must be realistic. Even with increasingly detailed nutrition information and evidence that diet affects health outcomes, convenience and taste remain the strongest determinants of food choices. It is up to health educators to clear up confusion and give consumers control with nutrition messages that are realistic, positive, easy to understand, and actionable without an expectation that consumers will surrender foods they love. PMID:26178023

Ship motion pattern directed VTOL letdown guidance
NASA Technical Reports Server (NTRS)
Phatak, A. V.; Karmali, M. S.; Paulk, C. H., Jr.
19830101
This paper examines ship motion pattern directed letdown guidance strategies for landing a VTOL aircraft onboard a small aviation ship under adverse environmental conditions. Offline computer simulation of the shipboard landing task is utilized for assessing the relative merits of the proposed guidance schemes. A sum of seventy sinusoids representation is used to model the ship motion time histories. The touchdown performance of a nonimal constantrateofdescent (CROD) letdown strategy serves as a benchmark for ranking the performance of the alternative letdown schemes.

Aeroassist flight experiment guidance, navigation and control
NASA Technical Reports Server (NTRS)
Brand, Timothy J.; Engel, Albert G.
19860101
The Aeroassist Flight Experiment scheduled for the early 1990's will demonstrate the use of a low L/D lifting brake using aerodynamic drag to return a spacecraft from a high energy to a low earth orbit. The experimental vehicle will be deployed and retrieved by the Shuttle Orbiter. This paper reviews some of the challenges, problems, and solutions encountered to date during guidance system development, with emphasis on technology advances which will benefit an operational Orbit Transfer Vehicle (OTV). Key factors to be discussed include guidance alternatives, aerodynamic modeling, navigation requirements, the impact of atmospheric uncertainties, and flight profile alternatives considered during initial planning.

CNES Approaching Guidance Experiment within FFIORD
NASA Technical Reports Server (NTRS)
Berges, JeanClaude; Cayeux, Philippe; GaudelVacaresse, Angelique; Meyssignac, Benoit
20070101
This article outlines the relative orbit control (guidance algorithm and its preliminary performance tests evaluation) that will be tested by the CNES Team on FFIORD (Formation Flying In Orbit Ranging Demonstration) onboard PRISMA mission. After a brief summary of the PRISMA mission context, the paper provides a full description of the rendezvous function involved in the approaching guidance experiment. This FFIORD onboard function is detailed in terms of onboard algorithmic method (basic algorithm and enhanced alternative), sensibility analysis used to construct maneuver plans and preliminary tests results.

POTW sludge sampling and analysis guidance document
SciTech Connect
Not Available
19890801
In view of the variability of municipal sludge quality, appropriate procedures must be followed to collect and analyze samples that accurately represent each POTW's sludge quality. The manual was developed to provide that guidance to POTW operators, engineers, managers, chemists and permit writers. It was intended to provide guidance in developing and implementing a sampling and analysis program, to gather information on sludge quality and determine compliance with permit conditions. The manual is based on current, stateoftheart field and laboratory practices and therefore is recommended for all sludge sampling and analysis programs.

Aerospace plane guidance using geometric control theory
NASA Technical Reports Server (NTRS)
Van Buren, Mark A.; Mease, Kenneth D.
19900101
A reducedorder method employing decomposition, based on timescale separation, of the 4D state space in a 2D slow manifold and a family of 2D fast manifolds is shown to provide an excellent approximation to the fullorder minimumfuel ascent trajectory. Nearoptimal guidance is obtained by tracking the reducedorder trajectory. The tracking problem is solved as regulation problems on the family of fast manifolds, using the exact linearization methodology from nonlinear geometric control theory. The validity of the overall guidance approach is indicated by simulation.

Ascent guidance algorithm using lidar wind measurements
NASA Technical Reports Server (NTRS)
Cramer, Evin J.; Bradt, Jerre E.; Hardtla, John W.
19900101
The formulation of a general nonlinear programming guidance algorithm that incorporates wind measurements in the computation of ascent guidance steering commands is discussed. A nonlinear programming (NLP) algorithm that is designed to solve a very general problem has the potential to address the diversity demanded by future launch systems. Using Bsplines for the command functional form allows the NLP algorithm to adjust the shape of the command profile to achieve optimal performance. The algorithm flexibility is demonstrated by simulation of ascent with dynamic loading constraints through a set of random wind profiles with and without wind sensing capability.

Discrete emotioncongruent false memories in the DRM paradigm.
PubMed
Bland, Cassandra E; Howe, Mark L; Knott, Lauren
20160801
Research has shown that falsememory production is enhanced for material that is emotionally congruent with the mood of the participant at the time of encoding. So far this research has only been conducted to examine the influence of generic negative affective mood states and generic negative stimuli on falsememory production. In addition, much of the research is limited as it focuses on valence and arousal dimensions, and fails to take into account the more comprehensive nature of emotions. The current study demonstrates that this effect goes beyond general negative or positive moods and acts at a more discrete emotional level. Participants underwent a standard emotioninduction procedure before listening to negative emotional or neutral associative word lists. The emotions induced, negative word lists, and associated nonpresented critical lures, were related to either fear or anger, 2 negative valence emotions that are also both high in arousal. Results showed that when valence and arousal are controlled for, false memories are more likely to be produced for discrete emotionally congruent compared with incongruent materials. These results support spreading activation theories of false remembering and add to our understanding of the adaptive nature of falsememory production. (PsycINFO Database Record PMID:26765099

Statespace supervision of reconfigurable discrete event systems
SciTech Connect
Garcia, H.E.; Ray, A.
19951231
The Discrete Event Systems (DES) theory of supervisory and state feedback control offers many advantages for implementing supervisory systems. Algorithmic concepts have been introduced to assure that the supervising algorithms are correct and meet the specifications. It is often assumed that the supervisory specifications are invariant or, at least, until a given supervisory task is completed. However, there are many practical applications where the supervising specifications update at real time. For example, in a Reconfigurable Discrete Event System (RDES) architecture, a bank of supervisors is defined to accommodate each identified operational condition or different supervisory specifications. This adaptive supervisory control system changes the supervisory configuration to accept coordinating commands or to adjust for changes in the controlled process. This paper addresses reconfiguration at the supervisory level of hybrid systems along with a RDES underlying architecture. It reviews the statebased supervisory control theory and extends it to the paradigm of RDES and in view of process control applications. The paper addresses theoretical issues with a limited number of practical examples. This control approach is particularly suitable for hierarchical reconfigurable hybrid implementations.

Bivariate discrete beta Kernel graduation of mortality data.
PubMed
Mazza, Angelo; Punzo, Antonio
20150701
Various parametric/nonparametric techniques have been proposed in literature to graduate mortality data as a function of age. Nonparametric approaches, as for example kernel smoothing regression, are often preferred because they do not assume any particular mortality law. Among the existing kernel smoothing approaches, the recently proposed (univariate) discrete beta kernel smoother has been shown to provide some benefits. Bivariate graduation, over age and calendar years or durations, is common practice in demography and actuarial sciences. In this paper, we generalize the discrete beta kernel smoother to the bivariate case, and we introduce an adaptive bandwidth variant that may provide additional benefits when data on exposures to the risk of death are available; furthermore, we outline a crossvalidation procedure for bandwidths selection. Using simulations studies, we compare the bivariate approach proposed here with its corresponding univariate formulation and with two popular nonparametric bivariate graduation techniques, based on Epanechnikov kernels and on Psplines. To make simulations realistic, a bivariate dataset, based on probabilities of dying recorded for the US males, is used. Simulations have confirmed the gain in performance of the new bivariate approach with respect to both the univariate and the bivariate competitors. PMID:25084764

On the consistency between nearestneighbor peridynamic discretizations and discretized classical elasticity models
DOE PAGESBeta
Seleson, Pablo; Du, Qiang; Parks, Michael L.
20160816
The peridynamic theory of solid mechanics is a nonlocal reformulation of the classical continuum mechanics theory. At the continuum level, it has been demonstrated that classical (local) elasticity is a special case of peridynamics. Such a connection between these theories has not been extensively explored at the discrete level. This paper investigates the consistency between nearestneighbor discretizations of linear elastic peridynamic models and finite difference discretizations of the Navier–Cauchy equation of classical elasticity. While nearestneighbor discretizations in peridynamics have been numerically observed to present griddependent crack paths or spurious microcracks, this paper focuses on a different, analytical aspect of suchmore » discretizations. We demonstrate that, even in the absence of cracks, such discretizations may be problematic unless a proper selection of weights is used. Specifically, we demonstrate that using the standard meshfree approach in peridynamics, nearestneighbor discretizations do not reduce, in general, to discretizations of corresponding classical models. We study nodalbased quadratures for the discretization of peridynamic models, and we derive quadrature weights that result in consistency between nearestneighbor discretizations of peridynamic models and discretized classical models. The quadrature weights that lead to such consistency are, however, model/discretizationdependent. We motivate the choice of those quadrature weights through a quadratic approximation of displacement fields. The stability of nearestneighbor peridynamic schemes is demonstrated through a Fourier mode analysis. Finally, an approach based on a normalization of peridynamic constitutive constants at the discrete level is explored. This approach results in the desired consistency for onedimensional models, but does not work in higher dimensions. The results of the work presented in this paper suggest that even though nearest

An analysis of physical guidance as reinforcement for noncompliance.
PubMed
Kern, Lee; Delaney, Beth A; Hilt, Alexandra; Bailin, Deborah E; Elliot, Christina
20020901
Physical guidance is a strategy commonly used for noncompliance. In two experiments, we evaluated reinforcing effects of physical guidance. Experiment 1 include three individuals with developmental disabilities who were noncompliant with tasks. Anecdotal observations indicated physical contact was highly reinforcing, and a functional analysis identified attention as a reinforcer for problem behavior. Two conditions compared physical guidance following noncompliance and no physical guidance following noncompliance. Results showed noncompliance increased for all three participants when physical guidance followed noncompliance. The second experiment empirically evaluated the function of noncompliance prior to examining the effect of physical guidance on noncompliance. A functional analysis, conducted with two participants, indicated noncompliance served an escape function for one and an attention function for the other. Comparisons of physical guidance and no physical guidance indicated physical guidance resulted in decreased noncompliance for the participant with an escape function but increased noncompliance for the participant with an attention function. PMID:12205825

PREFACE: 4th Symposium on Prospects in the Physics of Discrete Symmetries (DISCRETE2014)
NASA Astrophysics Data System (ADS)
Di Domenico, Antonio; Mavromatos, Nick E.; Mitsou, Vasiliki A.; Skliros, Dimitri P.
20150701
The DISCRETE 2014: Fourth Symposium in the Physics of Discrete Symmetries took place at King's College London, Strand Campus, London WC2R 2LS, from Tuesday, December 2 2014 till Saturday, December 6 2014. This is the fourth Edition of the DISCRETE conference series, which is a biannual event, having been held previously in Valencia (Discrete'08), Rome (Discrete2010) and Lisbon (Discrete2012). The topics covered at the DISCRETE series of conferences are: T, C, P, CP symmetries; accidental symmetries (B, L conservation); CPT symmetry, decoherence and entangled states, Lorentz symmetry breaking (phenomenology and current bounds); neutrino mass and mixing; implications for cosmology and astroparticle physics, dark matter searches; experimental prospects at LHC, new facilities. In DISCRETE 2014 we have also introduced two new topics: cosmological aspects of noncommutative spacetimes as well as PT symmetric Hamiltonians (nonHermitian but with real eigenvalues), a topic that has wide applications in particle physics and beyond. The conference was opened by the King's College London Vice Principal on Research and Innovation, Mr Chris Mottershead, followed by a welcome address by the Chair of DISCRETE 2014 (Professor Nick E. Mavromatos). After these introductory talks, the scientific programme of the DISCRETE 2014 symposium started. Following the tradition of DISCRETE series of conferences, the talks (138 in total) were divided into plenaryreview talks (25), invited research talks (50) and shorter presentations (63) — selected by the conveners of each session in consultation with the organisers — from the submitted abstracts. We have been fortunate to have very highquality, thought stimulating and interesting talks at all levels, which, together with the discussions among the participants, made the conference quite enjoyable. There were 152 registered participants for the event.

Adaptive techniques for LandauLifshitzGilbert equation with magnetostriction
NASA Astrophysics Data System (ADS)
Banas, L'ubomir
20080601
In this paper we propose a timespace adaptive method for micromagnetic problems with magnetostriction. The considered model consists of coupled Maxwell's, LandauLifshitzGilbert (LLG) and elastodynamic equations. The time discretization of Maxwell's equations and the elastodynamic equation is done by backward Euler method, the space discretization is based on Whitney edge elements and linear finite elements, respectively. The fully discrete LLG equation reduces to an ordinary differential equation, which is solved by an explicit method, that conserves the norm of the magnetization.

Direct adaptive control for nonlinear uncertain dynamical systems
NASA Astrophysics Data System (ADS)
Hayakawa, Tomohisa
In light of the complex and highly uncertain nature of dynamical systems requiring controls, it is not surprising that reliable system models for many high performance engineering and life science applications are unavailable. In the face of such high levels of system uncertainty, robust controllers may unnecessarily sacrifice system performance whereas adaptive controllers are clearly appropriate since they can tolerate far greater system uncertainty levels to improve system performance. In this dissertation, we develop a Lyapunovbased direct adaptive and neural adaptive control framework that addresses parametric uncertainty, unstructured uncertainty, disturbance rejection, amplitude and rate saturation constraints, and digital implementation issues. Specifically, we consider the following research topics; direct adaptive control for nonlinear uncertain systems with exogenous disturbances; robust adaptive control for nonlinear uncertain systems; adaptive control for nonlinear uncertain systems with actuator amplitude and rate saturation constraints; adaptive reducedorder dynamic compensation for nonlinear uncertain systems; direct adaptive control for nonlinear matrix secondorder dynamical systems with statedependent uncertainty; adaptive control for nonnegative and compartmental dynamical systems with applications to general anesthesia; direct adaptive control of nonnegative and compartmental dynamical systems with time delay; adaptive control for nonlinear nonnegative and compartmental dynamical systems with applications to clinical pharmacology; neural network adaptive control for nonlinear nonnegative dynamical systems; passivitybased neural network adaptive output feedback control for nonlinear nonnegative dynamical systems; neural network adaptive dynamic output feedback control for nonlinear nonnegative systems using tapped delay memory units; Lyapunovbased adaptive control framework for discretetime nonlinear systems with exogenous disturbances

Adapting Animals.
ERIC Educational Resources Information Center
Wedman, John; Wedman, Judy
19850101
The "Animals" program found on the Apple II and IIe system master disk can be adapted for use in the mathematics classroom. Instructions for making the necessary changes and suggestions for using it in lessons related to geometric shapes are provided. (JN)

Adaptive Thresholds
SciTech Connect
Bremer, P. T.
20140826
ADAPT is a topological analysis code that allow to compute local threshold, in particular relevance based thresholds for features defined in scalar fields. The initial target application is vortex detection but the software is more generally applicable to all threshold based feature definitions.

Adaptive homeostasis.
PubMed
Davies, Kelvin J A
20160601
Homeostasis is a central pillar of modern Physiology. The term homeostasis was invented by Walter Bradford Cannon in an attempt to extend and codify the principle of 'milieu intérieur,' or a constant interior bodily environment, that had previously been postulated by Claude Bernard. Clearly, 'milieu intérieur' and homeostasis have served us well for over a century. Nevertheless, research on signal transduction systems that regulate gene expression, or that cause biochemical alterations to existing enzymes, in response to external and internal stimuli, makes it clear that biological systems are continuously making shortterm adaptations both to setpoints, and to the range of 'normal' capacity. These transient adaptations typically occur in response to relatively mild changes in conditions, to programs of exercise training, or to subtoxic, nondamaging levels of chemical agents; thus, the terms hormesis, heterostasis, and allostasis are not accurate descriptors. Therefore, an operational adjustment to our understanding of homeostasis suggests that the modified term, Adaptive Homeostasis, may be useful especially in studies of stress, toxicology, disease, and aging. Adaptive Homeostasis may be defined as follows: 'The transient expansion or contraction of the homeostatic range in response to exposure to subtoxic, nondamaging, signaling molecules or events, or the removal or cessation of such molecules or events.' PMID:27112802

Domaindecomposable preconditioners for secondorder upwind discretizations of multicomponent systems
SciTech Connect
Keyes, D.E. . Dept. of Mechanical Engineering); Gropp, W.D. )
19900101
Discrete systems arising in computational fluid dynamics applications often require wide stencils adapted to the local convective direction in order to accommodate higherorder upwind differencing, and involve multiple components perhaps coupling strongly at each point. Conventional exactly or approximately factored inverses of such operators are burdensome to apply globally, especially in problems complicated by nontensorproduct domain geometry or adaptive refinement, though their forward'' action is not. Such problems can be solved by iterative methods by using either pointblock preconditioners or combination spacedecoupled/componentdecoupled preconditioners that are based on lowerorder discretizations. Except for a global implicit solve on a coarse grid, each phase in the application of such preconditioners has simple locally exploitable structure. 16 refs., 2 figs., 3 tabs.

Discrete Nonholonomic Lagrangian Systems on Lie Groupoids
NASA Astrophysics Data System (ADS)
Iglesias, David; Marrero, Juan C.; de Diego, David Martín; Martínez, Eduardo
20080601
This paper studies the construction of geometric integrators for nonholonomic systems. We develop a formalism for nonholonomic discrete Euler Lagrange equations in a setting that permits to deduce geometric integrators for continuous nonholonomic systems (reduced or not). The formalism is given in terms of Lie groupoids, specifying a discrete Lagrangian and a constraint submanifold on it. Additionally, it is necessary to fix a vector subbundle of the Lie algebroid associated to the Lie groupoid. We also discuss the existence of nonholonomic evolution operators in terms of the discrete nonholonomic Legendre transformations and in terms of adequate decompositions of the prolongation of the Lie groupoid. The characterization of the reversibility of the evolution operator and the discrete nonholonomic momentum equation are also considered. Finally, we illustrate with several classical examples the wide range of application of the theory (the discrete nonholonomic constrained particle, the Suslov system, the Chaplygin sleigh, the Veselova system, the rolling ball on a rotating table and the two wheeled planar mobile robot).

Parallel Adaptive Mesh Refinement
SciTech Connect
Diachin, L; Hornung, R; Plassmann, P; WIssink, A
20050304
As largescale, parallel computers have become more widely available and numerical models and algorithms have advanced, the range of physical phenomena that can be simulated has expanded dramatically. Many important science and engineering problems exhibit solutions with localized behavior where highlydetailed salient features or large gradients appear in certain regions which are separated by much larger regions where the solution is smooth. Examples include chemicallyreacting flows with radiative heat transfer, high Reynolds number flows interacting with solid objects, and combustion problems where the flame front is essentially a twodimensional sheet occupying a small part of a threedimensional domain. Modeling such problems numerically requires approximating the governing partial differential equations on a discrete domain, or grid. Grid spacing is an important factor in determining the accuracy and cost of a computation. A fine grid may be needed to resolve key local features while a much coarser grid may suffice elsewhere. Employing a fine grid everywhere may be inefficient at best and, at worst, may make an adequately resolved simulation impractical. Moreover, the location and resolution of fine grid required for an accurate solution is a dynamic property of a problem's transient features and may not be known a priori. Adaptive mesh refinement (AMR) is a technique that can be used with both structured and unstructured meshes to adjust local grid spacing dynamically to capture solution features with an appropriate degree of resolution. Thus, computational resources can be focused where and when they are needed most to efficiently achieve an accurate solution without incurring the cost of a globallyfine grid. Figure 1.1 shows two example computations using AMR; on the left is a structured mesh calculation of a impulsivelysheared contact surface and on the right is the fuselage and volume discretization of an RAH66 Comanche helicopter [35]. Note the

Quantitative Decision Support Requires Quantitative User Guidance
NASA Astrophysics Data System (ADS)
Smith, L. A.
20091201
Is it conceivable that models run on 2007 computer hardware could provide robust and credible probabilistic information for decision support and user guidance at the ZIP code level for subdaily meteorological events in 2060? In 2090? Retrospectively, how informative would output from today’s models have proven in 2003? or the 1930’s? Consultancies in the United Kingdom, including the Met Office, are offering services to “futureproof” their customers from climate change. How is a US or European based user or policy maker to determine the extent to which exciting new Bayesian methods are relevant here? or when a commercial supplier is vastly overselling the insights of today’s climate science? How are policy makers and academic economists to make the closely related decisions facing them? How can we communicate deep uncertainty in the future at small lengthscales without undermining the firm foundation established by climate science regarding global trends? Three distinct aspects of the communication of the uses of climate model output targeting users and policy makers, as well as other specialist adaptation scientists, are discussed. First, a brief scientific evaluation of the length and time scales at which climate model output is likely to become uninformative is provided, including a note on the applicability the latest Bayesian methodology to current stateoftheart general circulation models output. Second, a critical evaluation of the language often employed in communication of climate model output, a language which accurately states that models are “better”, have “improved” and now “include” and “simulate” relevant meteorological processed, without clearly identifying where the current information is thought to be uninformative and misleads, both for the current climate and as a function of the state of the (each) climate simulation. And thirdly, a general approach for evaluating the relevance of quantitative climate model output

A Workable Program of Career Guidance
ERIC Educational Resources Information Center
Hunt, Myrtle E.
19740101
Seven observations made by a career education team (a counselor, an occupational specialist, and classroom teachers) provided the basis for establishing career guidance goals. The goals were devoloped around the accepted elements of career education and implemented in a teachercounselor shared accountability effort in Florida's Pinellas County.…

Guidance for performing site inspections under CERCLA
SciTech Connect
Not Available
19920901
This guidance presents EPA`s site inspection (SI) strategy. The strategy discusses procedural guidelines to investigate potential Superfund (CERCLA) sites for evaluation pursuant to the Hazard Ranking System (HRS), revised in accordance with the Superfund Amendments and Reauthorization Act of 1986. The HRS is the primary means by which EPA evaluates sites for superfund`s National Priorities List (NPL).

Career Guidance and the Kuder Interest Inventories.
ERIC Educational Resources Information Center
Science Research Associates, Inc., Chicago, IL.
The manual suggests various uses the guidance counselor can make of the Kuder interest surveys. Written by a counselor, the guide presents suggestions that reflect considerable experience with the Kuder tests. Guidelines for introducing, administering, and interpreting the instrument are included along with suggestions for ways to involve the…

Advisory List of Instructional Media Guidance.
ERIC Educational Resources Information Center
North Carolina State Dept. of Public Instruction, Raleigh.
A bibliography of materials relevant to the competencybased guidance curriculum of the North Carolina State Department of Public Instruction is presented in this document. Books for students, books for teacher/counselor use, filmstrips (sound), and videocassettes are listed. Grade ranges are provided for each item, although use of the materials…

Guidance and control of flight vehicles
NASA Technical Reports Server (NTRS)
Breakwell, J. V.; Bryson, A. E., Jr.; Franklin, G. F.
19710101
Progress reports on guidance and attitude control mechanisms of different flight vehicles are presented. The vehicles considered include orbiting spacecraft, supersonic aircraft, and general aviation aircraft. Data also cover orbital transfer using low thrust, automatic landing logic for aircraft, optimal and three dimensional turns for supersonic aircraft, and orbital rendezvous.

Prevocational Exploration Guidance. Competency Based Curriculum.
ERIC Educational Resources Information Center
Harrington, Fred; And Others
This competencybased curriculum for prevocational exploration in West Virginia provides experiences at grades 9 and 10 related to exploring careers and educational programs for those careers. The guidance units are designed to assist the counselor in providing activities that relate to ongoing handson activities in prevocational business,…

75 FR 76011  Annual Guidance Agenda
Federal Register 2010, 2011, 2012, 2013, 2014
20101207
.... SUPPLEMENTARY INFORMATION: I. Background In the Federal Register of September 19, 2000 (65 FR 56468), FDA issued... existing guidance documents (65 FR 56468 at 56477; 21 CFR 10.115(f)(5)). The Agency is neither bound by... Administration, and Alkaline Phosphatase Activity 5100 Paint Branch Pkwy, (Compliance Policy Guide...

Guidance and Counseling Research in New Zealand.
ERIC Educational Resources Information Center
Small, J. J.
This review of guidance and counseling research includes reports of hypothesis testing based on hard data and behavioral analysis designs, reports of surveys and evaluations, and comments and recommenda tions from reflections on experience and survey findings. The materials, originating from New Zealand between 1970 and 1979, are classified on…

21 CFR 601.29  Guidance documents.
Code of Federal Regulations, 2011 CFR
20110401
... for Biologics Evaluation and Research (CBER) maintains a list of guidance documents that apply to the... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... Manufacturers Assistance (HFM40), Center for Biologics Evaluation and Research, Food and Drug...

21 CFR 314.445  Guidance documents.
Code of Federal Regulations, 2010 CFR
20100401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE APPLICATIONS FOR FDA APPROVAL TO MARKET A NEW DRUG Miscellaneous Provisions § 314.445 Guidance... comply with certain requirements of this part. (b) The Center for Drug Evaluation and Research...

21 CFR 601.29  Guidance documents.
Code of Federal Regulations, 2013 CFR
20130401
... for Biologics Evaluation and Research (CBER) maintains a list of guidance documents that apply to the... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... Manufacturers Assistance (HFM40), Center for Biologics Evaluation and Research, Food and Drug...

21 CFR 314.445  Guidance documents.
Code of Federal Regulations, 2013 CFR
20130401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE APPLICATIONS FOR FDA APPROVAL TO MARKET A NEW DRUG Miscellaneous Provisions § 314.445 Guidance... comply with certain requirements of this part. (b) The Center for Drug Evaluation and Research...

21 CFR 314.445  Guidance documents.
Code of Federal Regulations, 2014 CFR
20140401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE APPLICATIONS FOR FDA APPROVAL TO MARKET A NEW DRUG Miscellaneous Provisions § 314.445 Guidance... comply with certain requirements of this part. (b) The Center for Drug Evaluation and Research...

21 CFR 314.445  Guidance documents.
Code of Federal Regulations, 2012 CFR
20120401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE APPLICATIONS FOR FDA APPROVAL TO MARKET A NEW DRUG Miscellaneous Provisions § 314.445 Guidance... comply with certain requirements of this part. (b) The Center for Drug Evaluation and Research...

21 CFR 601.29  Guidance documents.
Code of Federal Regulations, 2014 CFR
20140401
... for Biologics Evaluation and Research (CBER) maintains a list of guidance documents that apply to the... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... Manufacturers Assistance (HFM40), Center for Biologics Evaluation and Research, Food and Drug...

21 CFR 601.29  Guidance documents.
Code of Federal Regulations, 2012 CFR
20120401
... for Biologics Evaluation and Research (CBER) maintains a list of guidance documents that apply to the... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... Manufacturers Assistance (HFM40), Center for Biologics Evaluation and Research, Food and Drug...

21 CFR 314.445  Guidance documents.
Code of Federal Regulations, 2011 CFR
20110401
... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE APPLICATIONS FOR FDA APPROVAL TO MARKET A NEW DRUG Miscellaneous Provisions § 314.445 Guidance... comply with certain requirements of this part. (b) The Center for Drug Evaluation and Research...

Museum Personnel's Opinions on Mobile Guidance Systems
ERIC Educational Resources Information Center
Yoshimura, Hirokazu; Sekiguchi, Hiromi; Yabumoto, Yoshitaka
20070101
While opinions from the general public are certainly important, opinions from the museum staff are also necessary to improve user service systems. this article introduces two groups of museum staff who have evaluated the usability of mobile guidance systems in Japanese museums. One group is the research team who used the PDA system in the National…

IUS guidance algorithm gamma guide assessment
NASA Technical Reports Server (NTRS)
Bray, R. E.; Dauro, V. A.
19800101
The Gamma Guidance Algorithm which controls the inertial upper stage is described. The results of an independent assessment of the algorithm's performance in satisfying the NASA missions' targeting objectives are presented. The results of a launch window analysis for a Galileo mission, and suggested improvements are included.

Vocational Guidance for Women, 19101940.
ERIC Educational Resources Information Center
Rossiter, Margaret W.
The kinds of vocational guidance available to women from 1910 to 1940 are discussed in this paper. As the number of women college graduates increased in the 1890s and especially in the first decade of the 20th century, concern also grew for what all these trained women would do to earn a living after they graduated and before they married (if they…

Middle School Students' Guidance and Counseling Needs
ERIC Educational Resources Information Center
Kesici, Sahin
20070101
The purpose of this study is to determine the guidance and counseling needs of middle school (i.e., sixth, seventh, and eighth grades) students from their points of views by using qualitative research techniques. In addition, while collecting the data, semistructured interview technique is used as a method of data collection. The study was…

Occupational Information. A Career Guidance View.
ERIC Educational Resources Information Center
Wolfbein, Seymour L.
This book deals not with the administrative or information searching processes related to the guidance function of providing occupational information, but with the substantive information itself. It presents a contemporary view of values, trends, and principles, derived primarily from statistical information describing the current world of work.…

78 FR 53792  Draft Guidance for Reciprocity
Federal Register 2010, 2011, 2012, 2013, 2014
20130830
... COMMISSION Draft Guidance for Reciprocity AGENCY: Nuclear Regulatory Commission. ACTION: Draft NUREG; request... for reciprocity. The NRC is requesting public comment on draft NUREG1556, Volume 19, Revision 1...@nrc.gov . The draft NUREG1556, Volume 19, Revision 1, is available under ADAMS Accession...

ASSESSMENT OF THE DEMONSTRATION GUIDANCE PROJECT.
ERIC Educational Resources Information Center
WRIGHTSTONE, J. WAYNE; AND OTHERS
THE PURPOSE WAS TO IDENTIFY ABLE STUDENTS FROM DISADVANTAGED URBAN AREAS AND TO STIMULATE THEM THROUGH CULTURAL EXPERIENCES, SPECIAL CLASSES, AND GUIDANCE TO SEEK HIGHER EDUCATIONAL AND VOCATIONAL GOALS. A PRIMARY OBJECTIVE WAS TO REFINE THE METHODS AND TECHNIQUES FOR PREDICTION OF ACADEMIC POTENTIAL, THROUGH APTITUDE TESTING, ACHIEVEMENT TESTING,…
