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Sample records for adaptive grouping technique

  1. Adaptive algebraic reconstruction technique

    SciTech Connect

    Lu Wenkai; Yin Fangfang

    2004-12-01

    Algebraic reconstruction techniques (ART) are iterative procedures for reconstructing objects from their projections. It is proven that ART can be computationally efficient by carefully arranging the order in which the collected data are accessed during the reconstruction procedure and adaptively adjusting the relaxation parameters. In this paper, an adaptive algebraic reconstruction technique (AART), which adopts the same projection access scheme in multilevel scheme algebraic reconstruction technique (MLS-ART), is proposed. By introducing adaptive adjustment of the relaxation parameters during the reconstruction procedure, one-iteration AART can produce reconstructions with better quality, in comparison with one-iteration MLS-ART. Furthermore, AART outperforms MLS-ART with improved computational efficiency.

  2. Adaptive techniques for troposcatter

    NASA Astrophysics Data System (ADS)

    Wallace, M. S.; Parl, S. A.; Malaga, A.; Pierce, J. N.

    1984-02-01

    This report examines the performance of phased array antennas with adaptive combining for troposcatter communications. Diversity is commonly employed to combat fading on troposcatter links. Diversity may be derived from a phased array by adaptive combining of the element outputs (space diversity) or equivalently by forming a set of beams via a Butler matrix transformation (angle diversity). A number of new results describing the performance of both azimuth and elevation angle diversity systems using phased arrays are derived and performance bounds for both azimuth and elevation diversity are found. A new class of sub-optimal combiners is examined. The effect of implicit diversity on wideband systems is considered. The degradation due to channel measurement errors is also determined. A measurement program is proposed to verify the results. The computer program which performs the common volume integration is described.

  3. Religious groups as adaptive units.

    PubMed

    Wilson, D S

    2001-01-01

    This essay provides a sketch of religion as a set of biologically and culturally evolved adaptations that enable human groups to function as adaptive units. Recent developments in evolutionary biology make such a group-level interpretation of religion more plausible than in the past. A brief survey of relevant concepts is followed by a relatively detailed interpretation of Calvinism as a religious system in which explicit behavioral prescriptions, beliefs about God and his relationship with people, and numerous social control mechanisms combined to change the city of Geneva from a collection of warring factions to a unified population.

  4. New Adaptive Optics Technique Demonstrated

    NASA Astrophysics Data System (ADS)

    2007-03-01

    four AO systems for the interferometric mode of the VLT). ESO PR Photo 19b/07 ESO PR Photo 19b/07 The Globular Cluster Omega Centauri (MAD/VLT) Present AO systems can only correct the effect of atmospheric turbulence in a relative small region of the sky - typically 15 arcseconds, the correction degrading very quickly when moving away from the central axis. Engineers have therefore developed new techniques to overcome this limitation, one of which is multi-conjugate adaptive optics (MCAO). At the end of 2003, ESO, together with partners in Italy and Portugal, started the development of a MCAO Demonstrator, named MAD. "The aim of MAD is to prove the feasibility and performances of new adaptive optics techniques, such as MCAO, meant to work on large fields of view and to serve as a very powerful test tool in understanding some of the critical issues that will determine the development of future instruments, for both the VLT and the Extremely Large Telescopes," said Norbert Hubin, head of the AO group at ESO. MAD is an advanced generation adaptive optics system, capable of compensating for the atmospheric turbulence disturbance on a large field of view (FoV) on the sky. It can successfully correct a 1-2 arcmin FoV, much larger than the ~15 arcsec typically provided by the existing adaptive optics facilities. MAD was fully developed and extensively characterized by ESO using a dedicated turbulence generator (MAPS, Multi Atmospheric Phase screens and Stars) able to reproduce in the laboratory the temporal evolution and the vertical structure of the turbulence observed at the Observatory. ESO PR Photo 19c/07 ESO PR Photo 19c/07 The MCAO Concept MAD was then disassembled and shipped to Paranal for re-integration at the Nasmyth Visitor focus of UT3. The integration took about 1 month, after which the system was ready for daylight testing and further characterization. "On the night of 25 March, we could successfully close the first MCAO loop on the open cluster NGC 3293," said

  5. Advanced Adaptive Optics Control Techniques

    DTIC Science & Technology

    1979-01-01

    Optimal estimation and control methods for high energy laser adaptive optics systems are described. Three system types are examined: Active...the adaptive optics approaches and potential system implementations are recommended.

  6. Research on Adaptive Antenna Techniques

    DTIC Science & Technology

    1977-01-01

    Jamming In an adaptive beamformer without obliteration of desired weak Input signals. However this method still has a major flaw in that the... Beamformer With Injected Noise (ABWIN). ^ Introduction to the Algorithm The basic idea behind the algorithm Is to feed Into an adaptive...the pilot signal of conventional adaptive beamformers I ]. The S* effect of a pilot signal constructed in this manner is described in a later section

  7. Adaptable recursive binary entropy coding technique

    NASA Astrophysics Data System (ADS)

    Kiely, Aaron B.; Klimesh, Matthew A.

    2002-07-01

    We present a novel data compression technique, called recursive interleaved entropy coding, that is based on recursive interleaving of variable-to variable length binary source codes. A compression module implementing this technique has the same functionality as arithmetic coding and can be used as the engine in various data compression algorithms. The encoder compresses a bit sequence by recursively encoding groups of bits that have similar estimated statistics, ordering the output in a way that is suited to the decoder. As a result, the decoder has low complexity. The encoding process for our technique is adaptable in that each bit to be encoded has an associated probability-of-zero estimate that may depend on previously encoded bits; this adaptability allows more effective compression. Recursive interleaved entropy coding may have advantages over arithmetic coding, including most notably the admission of a simple and fast decoder. Much variation is possible in the choice of component codes and in the interleaving structure, yielding coder designs of varying complexity and compression efficiency; coder designs that achieve arbitrarily small redundancy can be produced. We discuss coder design and performance estimation methods. We present practical encoding and decoding algorithms, as well as measured performance results.

  8. Group adaptation, formal darwinism and contextual analysis.

    PubMed

    Okasha, S; Paternotte, C

    2012-06-01

    We consider the question: under what circumstances can the concept of adaptation be applied to groups, rather than individuals? Gardner and Grafen (2009, J. Evol. Biol.22: 659-671) develop a novel approach to this question, building on Grafen's 'formal Darwinism' project, which defines adaptation in terms of links between evolutionary dynamics and optimization. They conclude that only clonal groups, and to a lesser extent groups in which reproductive competition is repressed, can be considered as adaptive units. We re-examine the conditions under which the selection-optimization links hold at the group level. We focus on an important distinction between two ways of understanding the links, which have different implications regarding group adaptationism. We show how the formal Darwinism approach can be reconciled with G.C. Williams' famous analysis of group adaptation, and we consider the relationships between group adaptation, the Price equation approach to multi-level selection, and the alternative approach based on contextual analysis. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  9. [Adaptive foundation of group-based reciprocity].

    PubMed

    Horita, Yutaka; Yamagishi, Toshio

    2010-06-01

    A one-shot sequential prisoner's dilemma game with an in-group and an out-group member was conducted to test the group heuristic hypothesis for the in-group bias in minimal groups. Eighty-nine participants played the role of a second player and faced a fully cooperative first player. The results showed that in-group bias occurred only in the common knowledge condition in which the first player and the second player mutually knew each other's group membership, but not in the private knowledge condition in which the first player did not know the second player's group membership. These results provide support for the group heuristic hypothesis that in-group bias is an adaptive strategy in an assumed generalized exchange system to avoid a bad reputation as a defector.

  10. Interframe Adaptive Data Compression Techniques for Images.

    DTIC Science & Technology

    1979-08-01

    1.3.1 Predictive Coding Techniques 8 1.3.2 Transform Coding Techniques 15 1.3.3 Hybrid Coding Techniques 17 1.4 Research Objectives 18 1.5 Description ...Chemical Plant Images 82 4.2.3 X-ray Projection Images 83 V INTERFRAME HYBRID CODING SCHEMES 91 5.1 Adaptive Interframe Hybrid Coding Scheme 95 5.2 Hybrid...Images 99 5.4.2 Chemical Plant Images 109 5.4.3 Angiocardiogram Images .7 777 T- - . vi Page VI DATA COMPRESSION FOR NOISY CHANNELS 117 6.1 Channel

  11. Improvements in Cesarean Section Techniques: Arad's Obstetrics Department Experience on Adapting the Vejnovic Cesarean Section Technique.

    PubMed

    Furau, Cristian; Furau, Gheorghe; Dascau, Voicu; Ciobanu, Gheorghe; Onel, Cristina; Stanescu, Casiana

    2013-09-01

    Cesarean section has become recently the first choice for delivery in many clinics in Romania and worldwide. The purpose of our study is to assess the benefits of introducing the adapted Vejnovic uterine suture technique into daily practice. A total of 1703 out of the 1776 cesarean section performed in the period January, 2012 - March, 2013 in the Obstetric Department of the Emergency Clinical County Hospital of Arad were retrospectively analyzed based on the cesarean section registries, birth registries and patient's personal medical records. We compared results between the group of patients undergoing adapted Vejnovic cesarean section technique and the group of patients operated in a classic manner. The cesarean section rate in the studied period was 56.48%. Adapted Vejnovic cesarean section technique was performed in 548 cases (30.86% of the cases), furthermore in the last 3 months studied it reached 57.27%. Mean APGAR score was better in the adapted Vejnovic cesarean section group (8.43) compared with the reference group (8.34). No significant differences were seen between the two groups regarding maternal age, gestation, weeks of gestation, newborn weight, anesthesia and indications for cesarean section. Exteriorizing the uterus helped the incidental diagnosis of 35 uterine myoma, 22 adnexal masses and 13 uterine malformations. In a society with a constant growth of cesarean rate, the adapted Vejnovic cesarean section technique is becoming popular amongst clinicians for its advantages, but further studies need to be developed for its standardization.

  12. Lie Group Techniques for Neural Learning

    DTIC Science & Technology

    2005-01-03

    Lie group techniques for Neural Learning Edinburgh June 2004 Elena Celledoni SINTEF Applied Mathematics, IMF-NTNU Lie group techniques for Neural...ORGANIZATION NAME(S) AND ADDRESS(ES) SINTEF Applied Mathematics, IMF-NTNU 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND

  13. The Use of the Nominal Group Technique.

    ERIC Educational Resources Information Center

    Mortensen, Mark A.; Holmes, Dallas L.

    The Nominal Group Technique (NGT), developed by Andre Delbecq and Andrew Van de Ven at the University of Wisconsin in the 1960s, is used to enhance the generation, exploration, and communication of ideas relevant to problem-solving situations. The NGT is unlike other typical interacting group techniques in that individuals work in the presence of…

  14. Adaptive node techniques for Maxwell's equations

    SciTech Connect

    Hewett, D W

    2000-04-01

    The computational mesh in numerical simulation provides a framework on which to monitor the spatial dependence of function and their derivatives. Spatial mesh is therefore essential to the ability to integrate systems in time without loss of fidelity. Several philosophies have emerged to provide such fidelity (Eulerian, Lagrangian, Arbitrary Lagrangian Eulerian ALE, Adaptive Mesh Refinement AMR, and adaptive node generation/deletion). Regardless of the type of mesh, a major difficulty is in setting up the initial mesh. Clearly a high density of grid points is essential in regions of high geometric complexity and/or regions of intense, energetic activity. For some problems, mesh generation is such a crucial part of the problem that it can take as much computational effort as the run itself, and these tasks are now taking weeks of massively parallel CPU time. Mesh generation is no less crucial to electromagnetic calculations. In fact EM problem set up can be even more challenging without the clues given by fluid motion in hydrodynamic systems. When the mesh is advected with the fluid (Lagrangian), mesh points naturally congregate in regions of high activity. Similarly in AMR algorithms, strong gradients in the fluid flow are one of the triggers for mesh refinement. In the hyperbolic Maxwell's equations without advection, mesh point placement/motion is not so intuitive. In fixed geometry systems, it at least feasible to finely mesh high leverage, geometrically challenged areas. For other systems, where the action takes place far from the boundaries and, likely, changes position in time, the options are limited to either using a high resolution (expensive) mesh in all regions that could require such resolution or adaptively generating nodes to resolve the physics as it evolves. The authors have developed a new time of adaptive node technique for Maxwell's equations to deal with this set of issues.

  15. Site-specific group selection drives locally adapted group compositions.

    PubMed

    Pruitt, Jonathan N; Goodnight, Charles J

    2014-10-16

    Group selection may be defined as selection caused by the differential extinction or proliferation of groups. The socially polymorphic spider Anelosimus studiosus exhibits a behavioural polymorphism in which females exhibit either a 'docile' or 'aggressive' behavioural phenotype. Natural colonies are composed of a mixture of related docile and aggressive individuals, and populations differ in colonies' characteristic docile:aggressive ratios. Using experimentally constructed colonies of known composition, here we demonstrate that population-level divergence in docile:aggressive ratios is driven by site-specific selection at the group level--certain ratios yield high survivorship at some sites but not others. Our data also indicate that colonies responded to the risk of extinction: perturbed colonies tended to adjust their composition over two generations to match the ratio characteristic of their native site, thus promoting their long-term survival in their natal habitat. However, colonies of displaced individuals continued to shift their compositions towards mixtures that would have promoted their survival had they remained at their home sites, regardless of their contemporary environment. Thus, the regulatory mechanisms that colonies use to adjust their composition appear to be locally adapted. Our data provide experimental evidence of group selection driving collective traits in wild populations.

  16. Reframing: A Therapeutic Technique in Group Counseling.

    ERIC Educational Resources Information Center

    Clark, Arthur J.

    1998-01-01

    Reframing is a therapeutic technique that assists individuals in broadening restricted perspectives. Its theoretical underpinnings are clarified in terms of systemic and solution-focused therapies, and Social Constructivism. Application of reframing technique in group counseling is discussed in terms of when to use, how to formulate, and…

  17. 75 FR 27814 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-18

    ...-W4] Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  18. 75 FR 34476 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Interior (Secretary) is renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and to provide recommendations to the Secretary...

  19. 71 FR 44042 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2006-08-03

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... (Secretary) is renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and provide recommendations to the Secretary...

  20. 73 FR 45070 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2008-08-01

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Interior (Secretary) is renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and to provide recommendations to the...

  1. Adaptive Control Techniques for Large Space Structures

    DTIC Science & Technology

    1987-12-23

    mission objectives. In particular, uncertainties in both system dynamics and disturbance spectra characterizations (both time varying and stochastic... uncertainty ) significantly limit the performance attainable with fixed gain, fixed architecture controls. Therefore, the use of an adaptive system , where...Theoretical Development: The initial emphasis has been on slow adaptation, since this covers may LSS situations. Later on we will examine fast adaptation. The

  2. A recursive technique for adaptive vector quantization

    NASA Technical Reports Server (NTRS)

    Lindsay, Robert A.

    1989-01-01

    Vector Quantization (VQ) is fast becoming an accepted, if not preferred method for image compression. The VQ performs well when compressing all types of imagery including Video, Electro-Optical (EO), Infrared (IR), Synthetic Aperture Radar (SAR), Multi-Spectral (MS), and digital map data. The only requirement is to change the codebook to switch the compressor from one image sensor to another. There are several approaches for designing codebooks for a vector quantizer. Adaptive Vector Quantization is a procedure that simultaneously designs codebooks as the data is being encoded or quantized. This is done by computing the centroid as a recursive moving average where the centroids move after every vector is encoded. When computing the centroid of a fixed set of vectors the resultant centroid is identical to the previous centroid calculation. This method of centroid calculation can be easily combined with VQ encoding techniques. The defined quantizer changes after every encoded vector by recursively updating the centroid of minimum distance which is the selected by the encoder. Since the quantizer is changing definition or states after every encoded vector, the decoder must now receive updates to the codebook. This is done as side information by multiplexing bits into the compressed source data.

  3. Using Creative Group Techniques in High Schools

    ERIC Educational Resources Information Center

    Veach, Laura J.; Gladding, Samuel T.

    2007-01-01

    Groups in high schools that use creative techniques help adolescents express their emotions appropriately, behave differently, and gain insight into themselves and others. This article looks at seven different creative arts media--music, movement, visual art, literature, drama, play, and humor--and offers examples of how they can be used in groups…

  4. Using Creative Group Techniques in High Schools

    ERIC Educational Resources Information Center

    Veach, Laura J.; Gladding, Samuel T.

    2007-01-01

    Groups in high schools that use creative techniques help adolescents express their emotions appropriately, behave differently, and gain insight into themselves and others. This article looks at seven different creative arts media--music, movement, visual art, literature, drama, play, and humor--and offers examples of how they can be used in groups…

  5. Software for the grouped optimal aggregation technique

    NASA Technical Reports Server (NTRS)

    Brown, P. M.; Shaw, G. W. (Principal Investigator)

    1982-01-01

    The grouped optimal aggregation technique produces minimum variance, unbiased estimates of acreage and production for countries, zones (states), or any designated collection of acreage strata. It uses yield predictions, historical acreage information, and direct acreage estimate from satellite data. The acreage strata are grouped in such a way that the ratio model over historical acreage provides a smaller variance than if the model were applied to each individual stratum. An optimal weighting matrix based on historical acreages, provides the link between incomplete direct acreage estimates and the total, current acreage estimate.

  6. Adaptive Control Techniques for Large Space Structures

    DTIC Science & Technology

    1989-01-06

    Point Analy- sis", submitted, IEEE Trans. on Circuits and Systems; Special Issue on Adaptive Systems, Sept. 1987. I.M.Y. Mareels, R.R. Bitmead, M. Gevers...adaptive system with unmodelled dynamics," Proc. IFAC Workshop on Adaptive Systems, San Francisco, CA. C.A. Desoer , R.W. Liu, J. Murray and R. Sacks...June 1980. C.A. Desoer and M. Vidyasagar, Feedback Systems: Input-Output Properties, Academic Press, * 1975. J.C. Doyle and G. Stein (1981

  7. 79 FR 3873 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2014-01-23

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group...-575) of 1992. The GCDAMP includes a Federal advisory committee, the AMWG, a technical work group...

  8. 79 FR 24748 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2014-05-01

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group..., the AMWG, a technical work group, a Grand Canyon Monitoring and Research Center, and...

  9. 62 FR 66384 - Glen Canyon Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    1997-12-18

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group AGENCY: Bureau of Reclamation, DOI. ACTION: Notice of public meeting. ] SUMMARY: The Glen Canyon Adaptive Management Work Group (AMWG) will... Work Group (1999 program, management objectives, approach to beach/habitat building flow...

  10. 80 FR 21261 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2015-04-17

    ....05940913.7000000] Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG... committee, the AMWG, a technical work group, a Grand Canyon Monitoring and Research Center, and...

  11. 65 FR 62750 - Glen Canyon Adaptive Management Work Group and Glen Canyon Technical Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-10-19

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group and Glen Canyon Technical Work Group... organized and includes a federal advisory committee (the Glen Canyon Adaptive Management Work Group, or AMWG), a technical work group (the Glen Canyon Technical Work Group, or TWG), a monitoring and...

  12. 76 FR 70751 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  13. 76 FR 34248 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  14. 75 FR 10501 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-08

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  15. 77 FR 50155 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-20

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  16. 75 FR 70947 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-19

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  17. 77 FR 30314 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-22

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  18. 76 FR 23621 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-27

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  19. 75 FR 17158 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  20. 77 FR 74203 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-13

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  1. 76 FR 52345 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-22

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  2. 75 FR 51284 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  3. 77 FR 10766 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-23

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  4. 76 FR 14044 - Trinity Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of meeting. SUMMARY: The Trinity Adaptive Management Working Group (TAMWG) affords stakeholders the opportunity to give policy, management, and technical input concerning Trinity River...

  5. 77 FR 43117 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-23

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand...

  6. 76 FR 24516 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand...

  7. 77 FR 9265 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-16

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand...

  8. 78 FR 21415 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand...

  9. 78 FR 7810 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand...

  10. Weighted adaptively grouped multilevel space time trellis codes

    NASA Astrophysics Data System (ADS)

    Jain, Dharmvir; Sharma, Sanjay

    2015-05-01

    In existing grouped multilevel space-time trellis codes (GMLSTTCs), the groups of transmit antennas are predefined, and the transmit power is equally distributed across all transmit antennas. When the channel parameters are perfectly known at the transmitter, adaptive antenna grouping and beamforming scheme can achieve the better performance by optimum grouping of transmit antennas and properly weighting transmitted signals based on the available channel information. In this paper, we present a new code designed by combining GMLSTTCs, adaptive antenna grouping and beamforming using the channel state information at transmitter (CSIT), henceforth referred to as weighted adaptively grouped multilevel space time trellis codes (WAGMLSTTCs). The CSIT is used to adaptively group the transmitting antennas and provide a beamforming scheme by allocating the different powers to the transmit antennas. Simulation results show that WAGMLSTTCs provide improvement in error performance of 2.6 dB over GMLSTTCs.

  11. The Emergence of Groups and Inequality through Co-Adaptation

    PubMed Central

    Atwell, Jon; Savit, Robert

    2016-01-01

    The emergence of groups and of inequality is often traced to pre-existing differences, exclusionary practices, or resource accumulation processes, but can the emergence of groups and their differential success simply be a feature of the behaviors of a priori equally-capable actors who have mutually adapted? Using a simple model of behavioral co-adaptation among agents whose individual actions construct a common environment, we present evidence that the formation of unequal groups is endemic to co-adaptive processes that endogenously alter the environment; agents tend to separate into two groups, one whose members stop adapting earliest (the in-group), and another comprising agents who continue to adapt (the out-group). Over a wide range of model parameters, members of the in-group are rewarded more on average than members of the out-group. The primary reason is that the in-group is able to have a more profound influence on the environment and mold it to the benefit of its members. This molding capacity proves more beneficial than the persistence of adaptivity, yet, crucially, which agents are able to form a coalition to successfully exert this control is strongly contingent on random aspects of the set of agent behaviors. In this paper, we present the model, relevant definitions, and results. We then discuss its implications for the study of complex adaptive systems generally. PMID:27362837

  12. Genomic Adaptation of the Lactobacillus casei Group

    PubMed Central

    Nakano, Akiyo; Takahata, Muneaki; Murakami, Masaru; Takaki, Takashi; Nishiyama, Hidetoshi; Igimi, Shizunobu; Hattori, Masahira; Morita, Hidetoshi

    2013-01-01

    Lactobacillus casei, L. paracasei, and L. rhamnosus form a closely related taxonomic group (Lactobacillus casei group) within the facultatively heterofermentative lactobacilli. Here, we report the complete genome sequences of L. paracasei JCM 8130 and L. casei ATCC 393, and the draft genome sequence of L. paracasei COM0101, all of which were isolated from daily products. Furthermore, we re-annotated the genome of L. rhamnosus ATCC 53103 (also known as L. rhamnosus GG), which we have previously reported. We confirmed that ATCC 393 is distinct from other strains previously described as L. paracasei. The core genome of 10 completely sequenced strains of the L. casei group comprised 1,682 protein-coding genes. Although extensive genome-wide synteny was found among the L. casei group, the genomes of ATCC 53103, JCM 8130, and ATCC 393 contained genomic islands compared with L. paracasei ATCC 334. Several genomic islands, including carbohydrate utilization gene clusters, were found at the same loci in the chromosomes of the L. casei group. The spaCBA pilus gene cluster, which was first identified in GG, was also found in other strains of the L. casei group, but several L. paracasei strains including COM0101 contained truncated spaC gene. ATCC 53103 encoded a higher number of proteins involved in carbohydrate utilization compared with intestinal lactobacilli, and extracellular adhesion proteins, several of which are absent in other strains of the L. casei group. In addition to previously fully sequenced L. rhamnosus and L. paracasei strains, the complete genome sequences of L. casei will provide valuable insights into the evolution of the L. casei group. PMID:24116025

  13. A novel bit-wise adaptable entropy coding technique

    NASA Technical Reports Server (NTRS)

    Kiely, A.; Klimesh, M.

    2001-01-01

    We present a novel entropy coding technique which is adaptable in that each bit to be encoded may have an associated probability esitmate which depends on previously encoded bits. The technique may have advantages over arithmetic coding. The technique can achieve arbitrarily small redundancy and admits a simple and fast decoder.

  14. Technique for adapting a spacer for a custom impression tray.

    PubMed

    Kaur, Harsimran; Nanda, Aditi; Verma, Mahesh; Koli, Dheeraj

    2016-12-01

    A method of adapting a spacer for the custom trays used to make a definite impression for complete dentures is presented. The technique can be used under a variety of conditions and offers several advantages.

  15. A novel online adaptive time delay identification technique

    NASA Astrophysics Data System (ADS)

    Bayrak, Alper; Tatlicioglu, Enver

    2016-05-01

    Time delay is a phenomenon which is common in signal processing, communication, control applications, etc. The special feature of time delay that makes it attractive is that it is a commonly faced problem in many systems. A literature search on time-delay identification highlights the fact that most studies focused on numerical solutions. In this study, a novel online adaptive time-delay identification technique is proposed. This technique is based on an adaptive update law through a minimum-maximum strategy which is firstly applied to time-delay identification. In the design of the adaptive identification law, Lyapunov-based stability analysis techniques are utilised. Several numerical simulations were conducted with Matlab/Simulink to evaluate the performance of the proposed technique. It is numerically demonstrated that the proposed technique works efficiently in identifying both constant and disturbed time delays, and is also robust to measurement noise.

  16. Speckle-adaptive VISAR fringe analysis technique

    NASA Astrophysics Data System (ADS)

    Erskine, David

    2017-01-01

    A line-VISAR (velocity interferometer) is an important diagnostic in shock physics, simultaneously measuring many fringe histories of adjacent portions of a target splayed along a line on a target, with fringes recorded vs time and space by a streak camera. Due to laser speckle the reflected intensity may be uneven spatially, and due to irregularities in the streak camera electron optics the phase along the slit may be slightly nonlinear. Conventional fringe analysis algorithms which do not properly model these variations can suffer from inferred velocity errors. A speckle-adaptive algorithm has been developed which senses the interferometer and illumination parameters for each individual row (spatial position Y) of the 2d interferogram, so that the interferogram can be compensated for Y-dependent nonfringing intensity, fringe visibility, and nonlinear phase distribution. In numerical simulations and on actual data we have found this individual row-by-row modeling improves the accuracy of the result, compared to a conventional column-by-column analysis approach.

  17. Multicriteria adaptation of robotic groups to dynamically changing conditions

    NASA Astrophysics Data System (ADS)

    Misyurin, S. Yu; Nelyubin, A. P.; Ivlev, V. I.

    2017-01-01

    A new approach is proposed to design complex robotic systems composed of many robots that can operate under different conditions and perform various tasks. Bio-inspired ideas of adaptation of robotic groups are discussed.

  18. 62 FR 42818 - Glen Canyon Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    1997-08-08

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior... Work Group (AMWG) will be an open public meeting to discuss administrative and program related issues. This meeting will discuss the following agenda items: Work Group organization, technical work...

  19. Modified Class II open sandwich restorations: evaluation of interfacial adaptation and influence of different restorative techniques.

    PubMed

    Andersson-Wenckert, Ingrid E; van Dijken, Jan W V; Hörstedt, Per

    2002-06-01

    The sandwich technique with resin-modified glass ionomer cement (RMGIC) has been proposed to relieve the contraction stresses of direct resin composite (RC) restorations. The aim of this study was to evaluate the interfacial adaptation to enamel and dentin of modified Class II open RMGIC/RC sandwich restorations and the influence of different light curing techniques and matrix bands. Forty box-shaped Class II fillings were placed in vivo in premolars scheduled for extraction after one month. In groups I and II, a metal matrix was used; RC was inserted with horizontal (group I) and diagonal (group II) increments and cured with indirect/direct light. Group III was performed as group II, but a transparent matrix was used. Group IV was as group II, but with a separating liner between RMGIC and RC. Group V was a closed sandwich restoration. Interfacial quality was studied using SEM replica technique. Gap-free interfacial adaptation to enamel was observed for RMGIC in 70%, for RC in 70% and to dentin for RMGIC in 81%, for RC in 56%. No significant differences were seen between the experimental groups. At the cervical margins, RMGIC showed significantly better adaptation to enamel than RC, 74% and 42%, respectively. In conclusion, the investigated restorations showed a high percentage of gap-free interfacial adaptation in vivo. Interfacial adaptation to dentin and to cervical enamel was significantly better for RMGIC than for RC.

  20. Technique and Facilitation of Developmental Groups.

    ERIC Educational Resources Information Center

    Meyer, Marilyn M.

    Counselors working with developmental groups need: (1) a thorough understanding of their group, (2) great skill, and (3) deep personal involvement. The author suggests specific characteristics for successful developmental groups: (1) the desire of the entire residence hall staff to be involved, (2) a co-ed group limited to eight members, and (3)…

  1. IPCC Working Group II: Impacts and Adaptation Part I

    NASA Astrophysics Data System (ADS)

    Pulwarty, R. S.

    2007-12-01

    The IPCC (as opposed to the UN Framework Convention) defines climate change as" any change in climate over time, whether due to natural variability or as a result of human activity". The IPCC Working Group II (Impacts, Adaptation, Vulnerability) was charged with assessing the scientific, technical, environmental, economic, and social aspects of vulnerability to climate change, and, the negative and positive consequences for ecological systems, socio-economic sectors, and human health. The Working Group II report focused on the following issues for different sectors and regions (e.g. water, agriculture, biodiversity) and communities (coastal, island, etc.): · The role of adaptation in reducing vulnerability and impacts, · Assessment of adaptation capacity, options and constraints, and · Enhancing adaptation practice and operations. This presentation will address the following questions in the context of the results of the IPCC Fourth Assessment Report WG II: · What are the barriers, knowledge gaps, and opportunities for impacts assessments? · How are decisions about adaptation being made, and what types of adaptation strategies are being undertaken? · What are good adaptation practices and how are they learned over time? Examples will be drawn from the freshwater resources, small islands and adaptation chapters to which the presenter contributed. Many lessons have been identified but few have been implemented or evaluated over time. Adaptation occurs in the context of multiple stresses. Adaptation will be important in coping with early impacts in the near-term and continue to be important as our climate changes, regardless of how that change is derived. It is important to note that unmitigated climate change could, in the long term, exceed the capacity of different natural, managed and human systems to adapt. The assessment leads to the following conclusions: · Adaptation to climate change is already taking place, but on a limited basis · Adaptation measures

  2. 77 FR 22801 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations and other management actions to protect resources downstream of Glen Canyon Dam...

  3. Application of adaptive antenna techniques to future commercial satellite communication

    NASA Technical Reports Server (NTRS)

    Ersoy, L.; Lee, E. A.; Matthews, E. W.

    1987-01-01

    The purpose of this contract was to identify the application of adaptive antenna technique in future operational commercial satellite communication systems and to quantify potential benefits. The contract consisted of two major subtasks. Task 1, Assessment of Future Commercial Satellite System Requirements, was generally referred to as the Adaptive section. Task 2 dealt with Pointing Error Compensation Study for a Multiple Scanning/Fixed Spot Beam Reflector Antenna System and was referred to as the reconfigurable system. Each of these tasks was further sub-divided into smaller subtasks. It should also be noted that the reconfigurable system is usually defined as an open-loop system while the adaptive system is a closed-loop system. The differences between the open- and closed-loop systems were defined. Both the adaptive and reconfigurable systems were explained and the potential applications of such systems were presented in the context of commercial communication satellite systems.

  4. Focus groups: a program planning technique.

    PubMed

    DesRosier, M B; Zellers, K C

    1989-03-01

    To successfully develop nurse retention programs, a thorough organizational analysis, including the identification of problems, is necessary. Used as a management tool, focus groups that use the organization's nursing staff provide a unique method of data collection for identifying problems that now exist in the organization. The authors discuss this method for obtaining information for strategic planning for retention of nurses.

  5. The Development of Group Interaction Patterns: How Groups become Adaptive, Generative, and Transformative Learners

    ERIC Educational Resources Information Center

    London, Manuel; Sessa, Valerie I.

    2007-01-01

    This article integrates the literature on group interaction process analysis and group learning, providing a framework for understanding how patterns of interaction develop. The model proposes how adaptive, generative, and transformative learning processes evolve and vary in their functionality. Environmental triggers for learning, the group's…

  6. [Adaptation Process to Group Home Living by Older Adults].

    PubMed

    Yoon, Hee Sook; Sok, Sohyune

    2016-12-01

    The purpose of the study was to explore and describe the adaptation process of older people to group homes. Participants were twenty older adults aged 65 or older who were living in group homes. Data were collected from January to April, 2015. In-depth unstructured interviews were conducted with individual participants. Data were analyzed using Strauss and Corbin's grounded theory method. From open coding, 100 concepts, 38 sub-categories, and 14 categories were identified. Analysis showed that the central phenomenon of the adaptation process of older people to group homes was 'gradually giving up'. Causal conditions were 'good-for-nothing body', contextual conditions were 'pushed', 'beleaguered'. Intervening conditions were 'reliable pillar: children', 'having affection more than having it from family: facility workers', 'comfort - like feeling at home', 'relieved: system'. Action/interaction strategies were 'facing the unfamiliar reality', 'building relationships with other people', 'accepting reality'. Consequences were 'a good place, more than expected', 'hope for the remaining days', 'waiting for a peaceful death'. The results of this study provide an in-depth understanding of the experience of the adaptation process of older people to group homes. The findings from this study can be used as basic data to establish policies to increase the number of small scale facilities which can help older adults adapt easily to the facilities.

  7. Adaptive radiation therapy for bladder cancer: a review of adaptive techniques used in clinical practice.

    PubMed

    Kibrom, Awet Z; Knight, Kellie A

    2015-12-01

    Significant changes in the shape, size and position of the bladder during radiotherapy (RT) treatment for bladder cancer have been correlated with high local failure rates; typically due to geographical misses. To account for this, large margins are added around the target volumes in conventional RT; however, this increases the volume of healthy tissue irradiation. The availability of cone beam computed tomography (CBCT) has not only allowed in-room volumetric imaging of the bladder, but also the development of adaptive radiotherapy (ART) for modification of plans to patient-specific changes. The aim of this review is to: (1) identify and explain the different ART techniques being used in clinical practice and (2) compare and contrast these different ART techniques to conventional RT in terms of target coverage and dose to healthy tissue: A literature search was conducted using EMBASE, MEDLINE and Scopus with the key words 'bladder, adaptive, radiotherapy/radiation therapy'. 11 studies were obtained that compared different adaptive RT techniques to conventional RT in terms of target volume coverage and healthy tissue sparing. All studies showed superior target volume coverage and/or healthy tissue sparing in adaptive RT compared to conventional RT. Cross-study comparison between different adaptive techniques could not be made due to the difference in protocols used in different studies. However, one study found daily re-optimisation of plans to be superior to plan of the day technique. The use of adaptive RT for bladder cancer is promising. Further study is required to assess adaptive RT versus conventional RT in terms of local control and long-term toxicity.

  8. A technique for characterizing the time course of odor adaptation in mice.

    PubMed

    Yoder, Wendy M; Munizza, Olivia; Lyman, Michelle; Smith, David W

    2014-09-01

    Although numerous studies have analyzed the temporal characteristics underlying olfactory adaptation at the level of the olfactory receptor neuron, to date, there have been no comparable behavioral measures in an animal model. In this study, odor adaptation was estimated in a group of mice employing a psychophysical technique recently developed for use in humans. The premise of this technique is that extended presentation of an odorant will produce odor adaptation, decreasing the sensitivity of the receptors and increasing thresholds for a brief, simultaneous target odorant presented at different time points on the adaptation contour; adaptation is estimated as the increase in threshold for a target odorant presented simultaneously with an adapting odorant, across varying adapting-to-target odorant onset delays. Previous research from our laboratory suggests that this method provides a reliable estimate of the onset time course of rapid adaptation in human subjects. Consistent with physiological and behavioral data from human subjects, the present findings demonstrate that measurable olfactory adaptive effects can be observed for odorant exposures as brief as 50-100ms, with asymptotic levels evident 400-600ms following adapting odorant onset. When compared with the adaptation contour in humans using the same odorant and stimulus paradigm, some differences in the onset characteristics are evident and may be related to sniffing behavior and to relative differences in thresholds. These data show that this psychophysical paradigm can be adapted for use in animal models, where experimental and genetic manipulations can be used to characterize the different mechanisms underlying odor adaptation. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. A Novel Monopulse Technique for Adaptive Phased Array Radar.

    PubMed

    Zhang, Xinyu; Li, Yang; Yang, Xiaopeng; Zheng, Le; Long, Teng; Baker, Christopher J

    2017-01-08

    The monopulse angle measuring technique is widely adopted in radar systems due to its simplicity and speed in accurately acquiring a target's angle. However, in a spatial adaptive array, beam distortion, due to adaptive beamforming, can result in serious deterioration of monopulse performance. In this paper, a novel constrained monopulse angle measuring algorithm is proposed for spatial adaptive arrays. This algorithm maintains the ability to suppress the unwanted signals without suffering from beam distortion. Compared with conventional adaptive monopulse methods, the proposed algorithm adopts a new form of constraint in forming the difference beam with the merit that it is more robust in most practical situations. At the same time, it also exhibits the simplicity of one-dimension monopulse, helping to make this algorithm even more appealing to use in adaptive planar arrays. The theoretical mean and variance of the proposed monopulse estimator is derived for theoretical analysis. Mathematical simulations are formulated to demonstrate the effectiveness and advantages of the proposed algorithm. Both theoretical analysis and simulation results show that the proposed algorithm can outperform the conventional adaptive monopulse methods in the presence of severe interference near the mainlobe.

  10. A Novel Monopulse Technique for Adaptive Phased Array Radar

    PubMed Central

    Zhang, Xinyu; Li, Yang; Yang, Xiaopeng; Zheng, Le; Long, Teng; Baker, Christopher J.

    2017-01-01

    The monopulse angle measuring technique is widely adopted in radar systems due to its simplicity and speed in accurately acquiring a target’s angle. However, in a spatial adaptive array, beam distortion, due to adaptive beamforming, can result in serious deterioration of monopulse performance. In this paper, a novel constrained monopulse angle measuring algorithm is proposed for spatial adaptive arrays. This algorithm maintains the ability to suppress the unwanted signals without suffering from beam distortion. Compared with conventional adaptive monopulse methods, the proposed algorithm adopts a new form of constraint in forming the difference beam with the merit that it is more robust in most practical situations. At the same time, it also exhibits the simplicity of one-dimension monopulse, helping to make this algorithm even more appealing to use in adaptive planar arrays. The theoretical mean and variance of the proposed monopulse estimator is derived for theoretical analysis. Mathematical simulations are formulated to demonstrate the effectiveness and advantages of the proposed algorithm. Both theoretical analysis and simulation results show that the proposed algorithm can outperform the conventional adaptive monopulse methods in the presence of severe interference near the mainlobe. PMID:28075348

  11. Adaptive registration of diffusion tensor images on lie groups

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Chen, LeiTing; Cai, HongBin; Qiu, Hang; Fei, Nanxi

    2016-08-01

    With diffusion tensor imaging (DTI), more exquisite information on tissue microstructure is provided for medical image processing. In this paper, we present a locally adaptive topology preserving method for DTI registration on Lie groups. The method aims to obtain more plausible diffeomorphisms for spatial transformations via accurate approximation for the local tangent space on the Lie group manifold. In order to capture an exact geometric structure of the Lie group, the local linear approximation is efficiently optimized by using the adaptive selection of the local neighborhood sizes on the given set of data points. Furthermore, numerical comparative experiments are conducted on both synthetic data and real DTI data to demonstrate that the proposed method yields a higher degree of topology preservation on a dense deformation tensor field while improving the registration accuracy.

  12. Adaptive differential correspondence imaging based on sorting technique

    NASA Astrophysics Data System (ADS)

    Wu, Heng; Zhang, Xianmin; Shan, Yilin; He, Zhenya; Li, Hai; Luo, Chunling

    2017-04-01

    We develop an adaptive differential correspondence imaging (CI) method using a sorting technique. Different from the conventional CI schemes, the bucket detector signals (BDS) are first processed by a differential technique, and then sorted in a descending (or ascending) order. Subsequently, according to the front and last several frames of the sorted BDS, the positive and negative subsets (PNS) are created by selecting the relative frames from the reference detector signals. Finally, the object image is recovered from the PNS. Besides, an adaptive method based on two-step iteration is designed to select the optimum number of frames. To verify the proposed method, a single-detector computational ghost imaging (GI) setup is constructed. We experimentally and numerically compare the performance of the proposed method with different GI algorithms. The results show that our method can improve the reconstruction quality and reduce the computation cost by using fewer measurement data.

  13. New MPLS network management techniques based on adaptive learning.

    PubMed

    Anjali, Tricha; Scoglio, Caterina; de Oliveira, Jaudelice Cavalcante

    2005-09-01

    The combined use of the differentiated services (DiffServ) and multiprotocol label switching (MPLS) technologies is envisioned to provide guaranteed quality of service (QoS) for multimedia traffic in IP networks, while effectively using network resources. These networks need to be managed adaptively to cope with the changing network conditions and provide satisfactory QoS. An efficient strategy is to map the traffic from different DiffServ classes of service on separate label switched paths (LSPs), which leads to distinct layers of MPLS networks corresponding to each DiffServ class. In this paper, three aspects of the management of such a layered MPLS network are discussed. In particular, an optimal technique for the setup of LSPs, capacity allocation of the LSPs and LSP routing are presented. The presented techniques are based on measurement of the network state to adapt the network configuration to changing traffic conditions.

  14. Adaptive remote sensing techniques implementing swarms of mobile agents

    NASA Astrophysics Data System (ADS)

    Cameron, Stewart M.; Loubriel, Guillermo M.; Robinett, Rush D., III; Stantz, Keith M.; Trahan, Michael W.; Wagner, John S.

    1999-07-01

    Measurement and signal intelligence of the battlespace has created new requirements in information management, communication and interoperability as they effect surveillance and situational awareness. In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical and difficult to characterize. An alternative approach is to implement adaptive remote-sensing techniques with swarms of mobile agents employing collective behavior for optimization of mapping signatures and positional orientation (registration). We have expanded intelligent control theory using physics-based collective behavior models and genetic algorithms to produce a uniquely powerful implementation of distributed ground-based measurement incorporating both local collective behavior, and niter-operative global optimization for sensor fusion and mission oversight. By using a layered hierarchical control architecture to orchestrate adaptive reconfiguration of semi-autonomous robotic agents, we can improve overall robustness and functionality in dynamic tactical environments without information bottlenecking.

  15. Marginal adaptation of composite resins under two adhesive techniques.

    PubMed

    Dačić, Stefan; Veselinović, Aleksandar M; Mitić, Aleksandar; Nikolić, Marija; Cenić, Milica; Dačić-Simonović, Dragica

    2016-11-01

    In the present research, different adhesive techniques were used to set up fillings with composite resins. After the application of etch and rinse or self etch adhesive technique, marginal adaptation of composite fillings was estimated by the length of margins without gaps, and by the microretention of resin in enamel and dentin. The study material consisted of 40 extracted teeth. Twenty Class V cavities were treated with 35% phosphorous acid and restored after rinsing by Adper Single Bond 2 and Filtek Ultimate-ASB/FU 3M ESPE composite system. The remaining 20 cavities were restored by Adper Easy One-AEO/FU 3M ESPE composite system. Marginal adaptation of composite fillings was examined using a scanning electron microscope (SEM). The etch and rinse adhesive technique showed a significantly higher percentage of margin length without gaps (in enamel: 92.5%, in dentin: 57.3%), compared with the self-etch technique with lower percentage of margin length without gaps, in enamel 70.4% (p < .001), and in dentin-22.6% (p < .05). In the first technique, microretention was composed of adhesive and hybrid layers as well as resin tugs in interprismatic spaces of enamel, while the dentin microretention was composed of adhesive and hybrid layers with resin tugs in dentin canals. In the second technique, resin tugs were rarely seen and a microgap was dominant along the border of restoration margins. The SEM analysis showed a better marginal adaptation of composite resin to enamel and dentin with better microretention when the etch and rinse adhesive procedure was applied.

  16. 78 FR 54482 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-04

    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... Canyon Dam Adaptive Management Work Group is in the public interest in connection with the performance of...

  17. 76 FR 54487 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... of the Glen Canyon Dam Adaptive Management Work Group is in the public interest in connection with...

  18. A successive overrelaxation iterative technique for an adaptive equalizer

    NASA Technical Reports Server (NTRS)

    Kosovych, O. S.

    1973-01-01

    An adaptive strategy for the equalization of pulse-amplitude-modulated signals in the presence of intersymbol interference and additive noise is reported. The successive overrelaxation iterative technique is used as the algorithm for the iterative adjustment of the equalizer coefficents during a training period for the minimization of the mean square error. With 2-cyclic and nonnegative Jacobi matrices substantial improvement is demonstrated in the rate of convergence over the commonly used gradient techniques. The Jacobi theorems are also extended to nonpositive Jacobi matrices. Numerical examples strongly indicate that the improvements obtained for the special cases are possible for general channel characteristics. The technique is analytically demonstrated to decrease the mean square error at each iteration for a large range of parameter values for light or moderate intersymbol interference and for small intervals for general channels. Analytically, convergence of the relaxation algorithm was proven in a noisy environment and the coefficient variance was demonstrated to be bounded.

  19. Fixed gain and adaptive techniques for rotorcraft vibration control

    NASA Technical Reports Server (NTRS)

    Roy, R. H.; Saberi, H. A.; Walker, R. A.

    1985-01-01

    The results of an analysis effort performed to demonstrate the feasibility of employing approximate dynamical models and frequency shaped cost functional control law desgin techniques for helicopter vibration suppression are presented. Both fixed gain and adaptive control designs based on linear second order dynamical models were implemented in a detailed Rotor Systems Research Aircraft (RSRA) simulation to validate these active vibration suppression control laws. Approximate models of fuselage flexibility were included in the RSRA simulation in order to more accurately characterize the structural dynamics. The results for both the fixed gain and adaptive approaches are promising and provide a foundation for pursuing further validation in more extensive simulation studies and in wind tunnel and/or flight tests.

  20. Adaptive resonator control techniques for high-power lasers

    SciTech Connect

    Freeman, R.H.; Spinhirne, J.M.; Anafi, D.

    1981-01-01

    Experimental results and interpretations for correcting tilt and astigmatism aberrations using intracavity adaptive optics versus extracavity adaptive optics are presented, along with control algorithm and resonator design considerations when utilizing a multidither COAT control system for astigmatism and tilt correction. It is shown that in a high-power device, PIB (Power-in-the-Bucket) optimization, with the possible added requirement of extracavity beam clean-up to achieve good beam quality, would be a more desirable control algorithm than BQ (beam quality) optimization. Zonal multidither hill-climbing servo COAT techniques applied to tilt correction fail to achieve good correction for large tilt amplitudes when the control loop is closed after tilt is introduced. Therefore, it is suggested that a separate tilt sensor be used to provide error signal for correction of tilt and let the multidither system COAT correct for higher order aberrations

  1. Rapid Structured Volume Grid Smoothing and Adaption Technique

    NASA Technical Reports Server (NTRS)

    Alter, Stephen J.

    2006-01-01

    A rapid, structured volume grid smoothing and adaption technique, based on signal processing methods, was developed and applied to the Shuttle Orbiter at hypervelocity flight conditions in support of the Columbia Accident Investigation. Because of the fast pace of the investigation, computational aerothermodynamicists, applying hypersonic viscous flow solving computational fluid dynamic (CFD) codes, refined and enhanced a grid for an undamaged baseline vehicle to assess a variety of damage scenarios. Of the many methods available to modify a structured grid, most are time-consuming and require significant user interaction. By casting the grid data into different coordinate systems, specifically two computational coordinates with arclength as the third coordinate, signal processing methods are used for filtering the data [Taubin, CG v/29 1995]. Using a reverse transformation, the processed data are used to smooth the Cartesian coordinates of the structured grids. By coupling the signal processing method with existing grid operations within the Volume Grid Manipulator tool, problems related to grid smoothing are solved efficiently and with minimal user interaction. Examples of these smoothing operations are illustrated for reductions in grid stretching and volume grid adaptation. In each of these examples, other techniques existed at the time of the Columbia accident, but the incorporation of signal processing techniques reduced the time to perform the corrections by nearly 60%. This reduction in time to perform the corrections therefore enabled the assessment of approximately twice the number of damage scenarios than previously possible during the allocated investigation time.

  2. Superpenetration optical microscopy by iterative multiphoton adaptive compensation technique

    PubMed Central

    Tang, Jianyong; Germain, Ronald N.; Cui, Meng

    2012-01-01

    Biological tissues are rarely transparent, presenting major challenges for deep tissue optical microscopy. The achievable imaging depth is fundamentally limited by wavefront distortions caused by aberration and random scattering. Here, we report an iterative wavefront compensation technique that takes advantage of the nonlinearity of multiphoton signals to determine and compensate for these distortions and to focus light inside deep tissues. Different from conventional adaptive optics methods, this technique can rapidly measure highly complicated wavefront distortions encountered in deep tissue imaging and provide compensations for not only aberration but random scattering. The technique is tested with a variety of highly heterogeneous biological samples including mouse brain tissue, skull, and lymph nodes. We show that high quality three-dimensional imaging can be realized at depths beyond the reach of conventional multiphoton microscopy and adaptive optics methods, albeit over restricted distances for a given correction. Moreover, the required laser excitation power can be greatly reduced in deep tissues, deviating from the power requirement of ballistic light excitation and thus significantly reducing photo damage to the biological tissue. PMID:22586078

  3. Rapid Structured Volume Grid Smoothing and Adaption Technique

    NASA Technical Reports Server (NTRS)

    Alter, Stephen J.

    2004-01-01

    A rapid, structured volume grid smoothing and adaption technique, based on signal processing methods, was developed and applied to the Shuttle Orbiter at hypervelocity flight conditions in support of the Columbia Accident Investigation. Because of the fast pace of the investigation, computational aerothermodynamicists, applying hypersonic viscous flow solving computational fluid dynamic (CFD) codes, refined and enhanced a grid for an undamaged baseline vehicle to assess a variety of damage scenarios. Of the many methods available to modify a structured grid, most are time-consuming and require significant user interaction. By casting the grid data into different coordinate systems, specifically two computational coordinates with arclength as the third coordinate, signal processing methods are used for filtering the data [Taubin, CG v/29 1995]. Using a reverse transformation, the processed data are used to smooth the Cartesian coordinates of the structured grids. By coupling the signal processing method with existing grid operations within the Volume Grid Manipulator tool, problems related to grid smoothing are solved efficiently and with minimal user interaction. Examples of these smoothing operations are illustrated for reduction in grid stretching and volume grid adaptation. In each of these examples, other techniques existed at the time of the Columbia accident, but the incorporation of signal processing techniques reduced the time to perform the corrections by nearly 60%. This reduction in time to perform the corrections therefore enabled the assessment of approximately twice the number of damage scenarios than previously possible during the allocated investigation time.

  4. Adaptive Grouping Distributed Compressive Sensing Reconstruction of Plant Hyperspectral Data.

    PubMed

    Xu, Ping; Liu, Junfeng; Xue, Lingyun; Zhang, Jingcheng; Qiu, Bo

    2017-06-07

    With the development of hyperspectral technology, to establish an effective spectral data compressive reconstruction method that can improve data storage, transmission, and maintaining spectral information is critical for quantitative remote sensing research and application in vegetation. The spectral adaptive grouping distributed compressive sensing (AGDCS) algorithm is proposed, which enables a distributed compressed sensing reconstruction of plant hyperspectral data. The spectral characteristics of hyperspectral data are analyzed and the joint sparse model is constructed. The spectral bands are adaptively grouped and the hyperspectral data are compressed and reconstructed on the basis of grouping. The experimental results showed that, compared with orthogonal matching pursuit (OMP) and gradient projection for sparse reconstruction (GPSR), AGDCS can significantly improve the visual effect of image reconstruction in the spatial domain. The peak signal-to-noise ratio (PSNR) at a low sampling rate (the sampling rate is lower than 0.2) increases by 13.72 dB than OMP and 1.66 dB than GPSR. In the spectral domain, the average normalized root mean square error, the mean absolute percentage error, and the mean absolute error of AGDCS is 35.38%, 31.83%, and 33.33% lower than GPSR, respectively. Additionally, AGDCS can achieve relatively high reconstructed efficiency.

  5. Adaptive Grouping Distributed Compressive Sensing Reconstruction of Plant Hyperspectral Data

    PubMed Central

    Xu, Ping; Liu, Junfeng; Xue, Lingyun; Zhang, Jingcheng; Qiu, Bo

    2017-01-01

    With the development of hyperspectral technology, to establish an effective spectral data compressive reconstruction method that can improve data storage, transmission, and maintaining spectral information is critical for quantitative remote sensing research and application in vegetation. The spectral adaptive grouping distributed compressive sensing (AGDCS) algorithm is proposed, which enables a distributed compressed sensing reconstruction of plant hyperspectral data. The spectral characteristics of hyperspectral data are analyzed and the joint sparse model is constructed. The spectral bands are adaptively grouped and the hyperspectral data are compressed and reconstructed on the basis of grouping. The experimental results showed that, compared with orthogonal matching pursuit (OMP) and gradient projection for sparse reconstruction (GPSR), AGDCS can significantly improve the visual effect of image reconstruction in the spatial domain. The peak signal-to-noise ratio (PSNR) at a low sampling rate (the sampling rate is lower than 0.2) increases by 13.72 dB than OMP and 1.66 dB than GPSR. In the spectral domain, the average normalized root mean square error, the mean absolute percentage error, and the mean absolute error of AGDCS is 35.38%, 31.83%, and 33.33% lower than GPSR, respectively. Additionally, AGDCS can achieve relatively high reconstructed efficiency. PMID:28590433

  6. Adaptive density partitioning technique in the auxiliary plane wave method

    NASA Astrophysics Data System (ADS)

    Kurashige, Yuki; Nakajima, Takahito; Hirao, Kimihiko

    2006-01-01

    We have developed the adaptive density partitioning technique (ADPT) in the auxiliary plane wave method, in which a part of the density is expanded to plane waves, for the fast evaluation of Coulomb matrix. Our partitioning is based on the error estimations and allows us to control the accuracy and efficiency. Moreover, we can drastically reduce the core Gaussian products that are left in Gaussian representation (its analytical integrals is the bottleneck in this method). For the taxol molecule with 6-31G** basis, the core Gaussian products accounted only for 5% in submicrohartree error.

  7. On a single step technique for adaptive array processing

    NASA Astrophysics Data System (ADS)

    Worms, Josef

    1986-07-01

    An improved adaptation algorithm designed for real time signal processing in antenna arrays is presented. The method is used for determining the filter weights in a sidelobe cancellation system. The Wiener filter equation is solved by using the well known Gauss-Seidel method and a sample matrix estimate. This algorithm (SSM - Single Step Method) combines rapid convergence and numerical stability. Compared with the direct SMI-technique and the Widrow LMS-algorithm, the properties of the proposed algorithm lead us to the conclusion that it is especially well suited for airborne antenna array applications.

  8. Small Group Teaching Techniques. Vocational Instructor Teaching Skills Project.

    ERIC Educational Resources Information Center

    Portland Community Coll., OR.

    This training module is intended to familiarize vocational education teachers with the techniques of small group instruction. It covers the following topics: the characteristics of a small group (participation, cooperation, controversy, and consensus); the benefits of learning in small groups (including promotion of active learning; student…

  9. Game Playing Techniques in Secondary School Counseling Groups

    ERIC Educational Resources Information Center

    Messing, Jeffrey; Elliott, Jacob J.

    1971-01-01

    Games are described as techniques for structuring a group situation to assist in acquiring cohesiveness. Discussed briefly are the Who Am I Game," the Lemon Game," the Face the Wall Game," and Would This Person Game." (Author/CJ)

  10. Game Playing Techniques in Secondary School Counseling Groups

    ERIC Educational Resources Information Center

    Messing, Jeffrey; Elliott, Jacob J.

    1971-01-01

    Games are described as techniques for structuring a group situation to assist in acquiring cohesiveness. Discussed briefly are the Who Am I Game," the Lemon Game," the Face the Wall Game," and Would This Person Game." (Author/CJ)

  11. 64 FR 54639 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-10-07

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work... Management Work Group, a technical work group, a monitoring and research center, and independent review... to act upon. DATES AND LOCATION: The Glen Canyon Adaptive Management Work Group will conduct two...

  12. 65 FR 9296 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-02-24

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work... ``Glen Canyon Dam Adaptive Management Work Group,'' a technical work group, a monitoring and research... meeting. The Glen Canyon Technical Work Group (TWG) will conduct one public meeting as follows: March...

  13. 65 FR 48731 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-08-09

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work... Management Work Group,'' a technical work group, a monitoring and research center, and independent review... Canyon Adaptive Management Work Group will conduct a public meeting: Phoenix, Arizona--January...

  14. Group psychotherapy in an acute inpatient setting: techniques that nourish self-esteem.

    PubMed

    Kurek-Ovshinsky, C

    1991-01-01

    This article describes a conceptual model and reparative techniques used in group therapy in a 15-bed acute inpatient psychiatric unit located in a 340-bed metropolitan trauma center. The group meets daily for 1 hr. The population reflects patients suffering from chronic mental illness and polysubstance abuse and those adapting to such complex medical problems as AIDS, spinal cord injuries, burns, and so forth. Using Roy and Roberts's (1981) adaptive modes of self-concept and interdependency, I describe how narcissism, the psychic structure designed to protect, repair, and restore the wounded self-esteem (Stolorow & Lachman, 1980), sustains group adaptations at the pregroup level. Lonergon (1980) described the pregroup phase as "parallel talk." It is similar to "parallel play" and generally reflects the developmental arrest or adaptive regression of individual group members. At this stage, group membership consists of a collection of individuals who use each other as an audience to whom they can express their narcissistic needs. Often, repeated blows to the patient's self-esteem result in a pervasive sense of powerlessness and helplessness. Patients gradually lose touch with their "real self" and become increasingly dependent on external cues to determine their feelings and behavior. The adaptive narcissistic need to depend on other people to feel whole suggests that group therapy can be a powerful tool in treating patients who suffer profound wounds to the self-esteem, prevalent in the population described. The reparative techniques used by the group therapist to initiate group involvement require the ability to tolerate and value a continuous pregroup phase. The patient with narcissistic behavior both craves and undermines attempts at group involvement.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Group Investigation Teaching Technique in Turkish Primary Science Courses

    ERIC Educational Resources Information Center

    Aksoy, Gokhan; Gurbuz, Fatih

    2013-01-01

    This study examined the effectiveness of group investigation teaching technique in teaching "Light" unit 7th grade primary science education level. This study was carried out in two different classes in the Primary school during the 2011-2012 academic year in Erzurum, Turkey. One of the classes was the Experimental Group (group…

  16. Applying perceptual and adaptive learning techniques for teaching introductory histopathology

    PubMed Central

    Krasne, Sally; Hillman, Joseph D.; Kellman, Philip J.; Drake, Thomas A.

    2013-01-01

    Background: Medical students are expected to master the ability to interpret histopathologic images, a difficult and time-consuming process. A major problem is the issue of transferring information learned from one example of a particular pathology to a new example. Recent advances in cognitive science have identified new approaches to address this problem. Methods: We adapted a new approach for enhancing pattern recognition of basic pathologic processes in skin histopathology images that utilizes perceptual learning techniques, allowing learners to see relevant structure in novel cases along with adaptive learning algorithms that space and sequence different categories (e.g. diagnoses) that appear during a learning session based on each learner's accuracy and response time (RT). We developed a perceptual and adaptive learning module (PALM) that utilized 261 unique images of cell injury, inflammation, neoplasia, or normal histology at low and high magnification. Accuracy and RT were tracked and integrated into a “Score” that reflected students rapid recognition of the pathologies and pre- and post-tests were given to assess the effectiveness. Results: Accuracy, RT and Scores significantly improved from the pre- to post-test with Scores showing much greater improvement than accuracy alone. Delayed post-tests with previously unseen cases, given after 6-7 weeks, showed a decline in accuracy relative to the post-test for 1st-year students, but not significantly so for 2nd-year students. However, the delayed post-test scores maintained a significant and large improvement relative to those of the pre-test for both 1st and 2nd year students suggesting good retention of pattern recognition. Student evaluations were very favorable. Conclusion: A web-based learning module based on the principles of cognitive science showed an evidence for improved recognition of histopathology patterns by medical students. PMID:24524000

  17. Applying perceptual and adaptive learning techniques for teaching introductory histopathology.

    PubMed

    Krasne, Sally; Hillman, Joseph D; Kellman, Philip J; Drake, Thomas A

    2013-01-01

    Medical students are expected to master the ability to interpret histopathologic images, a difficult and time-consuming process. A major problem is the issue of transferring information learned from one example of a particular pathology to a new example. Recent advances in cognitive science have identified new approaches to address this problem. We adapted a new approach for enhancing pattern recognition of basic pathologic processes in skin histopathology images that utilizes perceptual learning techniques, allowing learners to see relevant structure in novel cases along with adaptive learning algorithms that space and sequence different categories (e.g. diagnoses) that appear during a learning session based on each learner's accuracy and response time (RT). We developed a perceptual and adaptive learning module (PALM) that utilized 261 unique images of cell injury, inflammation, neoplasia, or normal histology at low and high magnification. Accuracy and RT were tracked and integrated into a "Score" that reflected students rapid recognition of the pathologies and pre- and post-tests were given to assess the effectiveness. Accuracy, RT and Scores significantly improved from the pre- to post-test with Scores showing much greater improvement than accuracy alone. Delayed post-tests with previously unseen cases, given after 6-7 weeks, showed a decline in accuracy relative to the post-test for 1(st)-year students, but not significantly so for 2(nd)-year students. However, the delayed post-test scores maintained a significant and large improvement relative to those of the pre-test for both 1(st) and 2(nd) year students suggesting good retention of pattern recognition. Student evaluations were very favorable. A web-based learning module based on the principles of cognitive science showed an evidence for improved recognition of histopathology patterns by medical students.

  18. Adaptive collective foraging in groups with conflicting nutritional needs

    PubMed Central

    Senior, Alistair M.; Lihoreau, Mathieu; Charleston, Michael A.; Buhl, Jerome; Raubenheimer, David; Simpson, Stephen J.

    2016-01-01

    Collective foraging, based on positive feedback and quorum responses, is believed to improve the foraging efficiency of animals. Nutritional models suggest that social information transfer increases the ability of foragers with closely aligned nutritional needs to find nutrients and maintain a balanced diet. However, whether or not collective foraging is adaptive in a heterogeneous group composed of individuals with differing nutritional needs is virtually unexplored. Here we develop an evolutionary agent-based model using concepts of nutritional ecology to address this knowledge gap. Our aim was to evaluate how collective foraging, mediated by social retention on foods, can improve nutrient balancing in individuals with different requirements. The model suggests that in groups where inter-individual nutritional needs are unimodally distributed, high levels of collective foraging yield optimal individual fitness by reducing search times that result from moving between nutritionally imbalanced foods. However, where nutritional needs are highly bimodal (e.g. where the requirements of males and females differ) collective foraging is selected against, leading to group fission. In this case, additional mechanisms such as assortative interactions can coevolve to allow collective foraging by subgroups of individuals with aligned requirements. Our findings indicate that collective foraging is an efficient strategy for nutrient regulation in animals inhabiting complex nutritional environments and exhibiting a range of social forms. PMID:27152206

  19. Adaptive pseudo dilation for gestalt edge grouping and contour detection.

    PubMed

    Papari, Giuseppe; Petkov, Nicolai

    2008-10-01

    We consider the problem of detecting object contours in natural images. In many cases, local luminance changes turn out to be stronger in textured areas than on object contours. Therefore, local edge features, which only look at a small neighborhood of each pixel, cannot be reliable indicators of the presence of a contour, and some global analysis is needed. We introduce a new morphological operator, called adaptive pseudo-dilation (APD), which uses context dependent structuring elements in order to identify long curvilinear structure in the edge map. We show that grouping edge pixels as the connected components of the output of APD results in a good agreement with the gestalt law of good continuation. The novelty of this operator is that dilation is limited to the Voronoi cell of each edge pixel. An efficient implementation of APD is presented. The grouping algorithm is then embedded in a multithreshold contour detector. At each threshold level, small groups of edges are removed, and contours are completed by means of a generalized reconstruction from markers. The use of different thresholds makes the algorithm much less sensitive to the values of the input parameters. Both qualitative and quantitative comparison with existing approaches prove the superiority of the proposed contour detector in terms of larger amount of suppressed texture and more effective detection of low-contrast contours.

  20. Adaptive collective foraging in groups with conflicting nutritional needs.

    PubMed

    Senior, Alistair M; Lihoreau, Mathieu; Charleston, Michael A; Buhl, Jerome; Raubenheimer, David; Simpson, Stephen J

    2016-04-01

    Collective foraging, based on positive feedback and quorum responses, is believed to improve the foraging efficiency of animals. Nutritional models suggest that social information transfer increases the ability of foragers with closely aligned nutritional needs to find nutrients and maintain a balanced diet. However, whether or not collective foraging is adaptive in a heterogeneous group composed of individuals with differing nutritional needs is virtually unexplored. Here we develop an evolutionary agent-based model using concepts of nutritional ecology to address this knowledge gap. Our aim was to evaluate how collective foraging, mediated by social retention on foods, can improve nutrient balancing in individuals with different requirements. The model suggests that in groups where inter-individual nutritional needs are unimodally distributed, high levels of collective foraging yield optimal individual fitness by reducing search times that result from moving between nutritionally imbalanced foods. However, where nutritional needs are highly bimodal (e.g. where the requirements of males and females differ) collective foraging is selected against, leading to group fission. In this case, additional mechanisms such as assortative interactions can coevolve to allow collective foraging by subgroups of individuals with aligned requirements. Our findings indicate that collective foraging is an efficient strategy for nutrient regulation in animals inhabiting complex nutritional environments and exhibiting a range of social forms.

  1. A Solution Adaptive Technique Using Tetrahedral Unstructured Grids

    NASA Technical Reports Server (NTRS)

    Pirzadeh, Shahyar Z.

    2000-01-01

    An adaptive unstructured grid refinement technique has been developed and successfully applied to several three dimensional inviscid flow test cases. The method is based on a combination of surface mesh subdivision and local remeshing of the volume grid Simple functions of flow quantities are employed to detect dominant features of the flowfield The method is designed for modular coupling with various error/feature analyzers and flow solvers. Several steady-state, inviscid flow test cases are presented to demonstrate the applicability of the method for solving practical three-dimensional problems. In all cases, accurate solutions featuring complex, nonlinear flow phenomena such as shock waves and vortices have been generated automatically and efficiently.

  2. Adaptive and robust techniques (ART) for thermoacoustic and photoacoustic tomography

    NASA Astrophysics Data System (ADS)

    Xie, Yao; Guo, Bin; Li, Jian; Ku, Geng; Wang, Lihong V.

    2007-02-01

    In this paper, we present new Adaptive and Robust Techniques (ART) for microwave-based thermoacoustic tomography (TAT) and laser-based photo-acoustic tomography (PAT), and study their performances for breast cancer detection. TAT and PAT are emerging medical imaging techniques that combine the merits of high contrast due to electromagnetic or laser stimulation and high resolution offered by thermal acoustic imaging. The current image reconstruction methods used for TAT and PAT, such as the widely used Delay-and-Sum (DAS) approach, are data-independent and suffer from low resolution, high sidelobe levels, and poor interference rejection capabilities. The data-adaptive ART can have much better resolution and much better interference rejection capabilities than their data-independent counterparts. By allowing certain uncertainties, ART can be used to mitigate the amplitude and phase distortion problems encountered in TAT and PAT. Specifically, in the first step of ART, RCB is used for waveform estimation by treating the amplitude distortion with an uncertainty parameter. In the second step of ART, a simple yet effective peak searching method is used for phase distortion correction. Compared with other energy or amplitude based response intensity estimation methods, peak searching can be used to improve image quality with little additional computational costs. Moreover, since the acoustic pulse is usually bipolar: a positive peak, corresponding to the compression pulse, and a negative peak, corresponding to the rarefaction pulse, we can further enhance the image contrast in TAT or PAT by using the peak-to-peak difference as the response intensity for a focal point. The excellent performance of ART is demonstrated using both simulated and experimentally measured data.

  3. Cross-section adjustment techniques for BWR adaptive simulation

    NASA Astrophysics Data System (ADS)

    Jessee, Matthew Anderson

    Computational capability has been developed to adjust multi-group neutron cross-sections to improve the fidelity of boiling water reactor (BWR) modeling and simulation. The method involves propagating multi-group neutron cross-section uncertainties through BWR computational models to evaluate uncertainties in key core attributes such as core k-effective, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then employed to adjust multi-group cross-sections to minimize the disagreement between BWR modeling predictions and measured plant data. For this work, measured plant data were virtually simulated in the form of perturbed 3-D nodal power distributions with discrepancies with predictions of the same order of magnitude as expected from plant data. Using the simulated plant data, multi-group cross-section adjustment reduces the error in core k-effective to less than 0.2% and the RMS error in nodal power to 4% (i.e. the noise level of the in-core instrumentation). To ensure that the adapted BWR model predictions are robust, Tikhonov regularization is utilized to control the magnitude of the cross-section adjustment. In contrast to few-group cross-section adjustment, which was the focus of previous research on BWR adaptive simulation, multigroup cross-section adjustment allows for future fuel cycle design optimization to include the determination of optimal fresh fuel assembly designs using the adjusted multi-group cross-sections. The major focus of this work is to efficiently propagate multi-group neutron cross-section uncertainty through BWR lattice physics calculations. Basic neutron cross-section uncertainties are provided in the form of multi-group cross-section covariance matrices. For energy groups in the resolved resonance energy range, the cross-section uncertainties are computed using an infinitely-dilute approximation of the neutron flux. In order to accurately account for spatial and

  4. Postural adaptations specific to preferred throwing techniques practiced by competition-level judoists.

    PubMed

    Paillard, Thierry; Montoya, Richard; Dupui, Philippe

    2007-04-01

    The purpose of this study was to analyse the judoists' postural regulation adopted to accommodate their favorite throwing technique (tokui-waza). The tokui-waza is a technique performed in bipodal or monopodal stance. Twenty three judoists aged between 16 and 20 took part in the protocol. All had a minimum regional sportive level. They were separated into two groups: the one performed a tokui-waza in bipodal stance (BS group) and the others performed a tokui-waza in monopodal stance (MS group). The medio/lateral and antero/posterior dynamic balance was evaluated on one-leg and two-leg support with a seesaw platform laid on a force platform. On two-leg support, the BS group judoists were more efficient than the MS group judoists. On the contrary, on one-leg support, the MS group was more efficient than the BS group. The different movements practiced on one or two-leg induce specific postural adaptations in competition-level judoists. Therefore, the present study shows that the different movements practiced in a given sport can induce particular postural adaptations. This phenomenon must therefore also be taken into account in the protocols used for evaluating postural control in sportsmen.

  5. Adapting liver motion models using a navigator channel technique

    PubMed Central

    Nguyen, T-N.; Moseley, J. L.; Dawson, L. A.; Jaffray, D. A.; Brock, K. K.

    2009-01-01

    Deformable registration can improve the accuracy of tumor targeting; however for online applications, efficiency as well as accuracy is important. A navigator channel technique has been developed to combine a biomechanical model-based deformable registration algorithm with a population motion model and patient specific motion information to perform fast deformable registration for application in image-guided radiation therapy. A respiratory population-based liver motion model was generated from breath-hold CT data sets of ten patients using a finite element model as a framework. The population model provides a biomechanical reference template of the average liver motions, which were found to be (absolute mean±SD) 0.12±0.10, 0.84±0.13, and 1.24±0.18 cm in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions, respectively. The population motion model was then adapted to the specific liver motion of 13 patients based on their exhale and inhale CT images. The patient motion was calculated using a navigator channel (a narrow region of interest window) on liver boundaries in the images. The absolute average accuracy of the navigator channel to predict the 1D SI and AP motions of the liver was less than 0.11, which is less than the out-of-plane image voxel size, 0.25 cm. This 1D information was then used to adapt the 4D population motion model in the SI and AP directions to predict the patient specific liver motion. The absolute average residual error of the navigator channel technique to adapt the population motion to the patients’ specific motion was verified using three verification methods: (1) vessel bifurcation, (2) tumor center of mass, and (3) MORFEUS deformable algorithm. All three verification methods showed statistically similar results where the technique’s accuracy was approximately on the order of the voxel image sizes. This method has potential applications in online assessment of motion at the time of treatment to

  6. 65 FR 15173 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-03-21

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice; correction. SUMMARY: The Bureau of... an upcoming public meeting of the Glen Canyon Dam Adaptive Management Work Group. The meeting...

  7. 66 FR 8980 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2001-02-05

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work... has been organized and includes a federal advisory committee (the AMWG), a technical work group (the...: The Adaptive Management Work Group will conduct the following public meetings: Phoenix,...

  8. 63 FR 69304 - Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    1998-12-16

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meetings. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group will conduct an open public meeting to...

  9. Adaptive-compression based congestion control technique for wireless sensor networks.

    PubMed

    Lee, Joa-Hyoung; Jung, In-Bum

    2010-01-01

    Congestion in a wireless sensor network causes an increase in the amount of data loss and delays in data transmission. In this paper, we propose a new congestion control technique (ACT, Adaptive Compression-based congestion control Technique) based on an adaptive compression scheme for packet reduction in case of congestion. The compression techniques used in the ACT are Discrete Wavelet Transform (DWT), Adaptive Differential Pulse Code Modulation (ADPCM), and Run-Length Coding (RLC). The ACT first transforms the data from the time domain to the frequency domain, reduces the range of data by using ADPCM, and then reduces the number of packets with the help of RLC before transferring the data to the source node. It introduces the DWT for priority-based congestion control because the DWT classifies the data into four groups with different frequencies. The ACT assigns priorities to these data groups in an inverse proportion to the respective frequencies of the data groups and defines the quantization step size of ADPCM in an inverse proportion to the priorities. RLC generates a smaller number of packets for a data group with a low priority. In the relaying node, the ACT reduces the amount of packets by increasing the quantization step size of ADPCM in case of congestion. Moreover, in order to facilitate the back pressure, the queue is controlled adaptively according to the congestion state. We experimentally demonstrate that the ACT increases the network efficiency and guarantees fairness to sensor nodes, as compared with the existing methods. Moreover, it exhibits a very high ratio of the available data in the sink.

  10. Adaptive-Compression Based Congestion Control Technique for Wireless Sensor Networks

    PubMed Central

    Lee, Joa-Hyoung; Jung, In-Bum

    2010-01-01

    Congestion in a wireless sensor network causes an increase in the amount of data loss and delays in data transmission. In this paper, we propose a new congestion control technique (ACT, Adaptive Compression-based congestion control Technique) based on an adaptive compression scheme for packet reduction in case of congestion. The compression techniques used in the ACT are Discrete Wavelet Transform (DWT), Adaptive Differential Pulse Code Modulation (ADPCM), and Run-Length Coding (RLC). The ACT first transforms the data from the time domain to the frequency domain, reduces the range of data by using ADPCM, and then reduces the number of packets with the help of RLC before transferring the data to the source node. It introduces the DWT for priority-based congestion control because the DWT classifies the data into four groups with different frequencies. The ACT assigns priorities to these data groups in an inverse proportion to the respective frequencies of the data groups and defines the quantization step size of ADPCM in an inverse proportion to the priorities. RLC generates a smaller number of packets for a data group with a low priority. In the relaying node, the ACT reduces the amount of packets by increasing the quantization step size of ADPCM in case of congestion. Moreover, in order to facilitate the back pressure, the queue is controlled adaptively according to the congestion state. We experimentally demonstrate that the ACT increases the network efficiency and guarantees fairness to sensor nodes, as compared with the existing methods. Moreover, it exhibits a very high ratio of the available data in the sink. PMID:22319280

  11. Optical techniques to understand biofunctional adaptation in human dentine

    NASA Astrophysics Data System (ADS)

    Kishen, Anil; Asundi, Anand K.

    2004-08-01

    Human tooth structure in the oral environment is subjected to mechanical forces and thermal fluctuations. Dentine, the major component of the tooth structure, is a bio-composite, mainly composed of a highly mineralized phase and a collagenous phase. When subjected to changes in load and/or temperature, dentine will experience stresses and strains distribution within their structure. Though such effects are found to cause deleterious effects on artificial dental restorations, biological structures such as dentine seem to posses an inherent ability to adapt to functional thermo-mechanical loads. Optical techniques enable visualization and quantification of deformation, strain and stress on dental structures and provide a better understanding on their thermo-mechanical response. In this study 2-dimensional and 3-dimensional digital photoelasticity, digital moiré interferometry and Electronic Speckle Pattern Interferometry (ESPI) are all shown to be quite promising in this application. This paper will highlight these techniques and the corresponding applications. These experiments will aid in designing and development of better dental restorations and implants in clinical practice.

  12. Sensor Web Dynamic Measurement Techniques and Adaptive Observing Strategies

    NASA Technical Reports Server (NTRS)

    Talabac, Stephen J.

    2004-01-01

    Sensor Web observing systems may have the potential to significantly improve our ability to monitor, understand, and predict the evolution of rapidly evolving, transient, or variable environmental features and events. This improvement will come about by integrating novel data collection techniques, new or improved instruments, emerging communications technologies and protocols, sensor mark-up languages, and interoperable planning and scheduling systems. In contrast to today's observing systems, "event-driven" sensor webs will synthesize real- or near-real time measurements and information from other platforms and then react by reconfiguring the platforms and instruments to invoke new measurement modes and adaptive observation strategies. Similarly, "model-driven" sensor webs will utilize environmental prediction models to initiate targeted sensor measurements or to use a new observing strategy. The sensor web concept contrasts with today's data collection techniques and observing system operations concepts where independent measurements are made by remote sensing and in situ platforms that do not share, and therefore cannot act upon, potentially useful complementary sensor measurement data and platform state information. This presentation describes NASA's view of event-driven and model-driven Sensor Webs and highlights several research and development activities at the Goddard Space Flight Center.

  13. Group decision-making techniques for natural resource management applications

    USGS Publications Warehouse

    Coughlan, Beth A.K.; Armour, Carl L.

    1992-01-01

    This report is an introduction to decision analysis and problem-solving techniques for professionals in natural resource management. Although these managers are often called upon to make complex decisions, their training in the natural sciences seldom provides exposure to the decision-making tools developed in management science. Our purpose is to being to fill this gap. We present a general analysis of the pitfalls of group problem solving, and suggestions for improved interactions followed by the specific techniques. Selected techniques are illustrated. The material is easy to understand and apply without previous training or excessive study and is applicable to natural resource management issues.

  14. 69 FR 41278 - Glen Canyon Dam Adaptive Management Work Group; Notice of Renewal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2004-07-08

    ... Office of the Secretary Glen Canyon Dam Adaptive Management Work Group; Notice of Renewal This notice is... of the Interior (Secretary) is renewing the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and provide recommendations to the...

  15. 64 FR 173 - Glen Canyon Dam Adaptive Management Work Group; Notice of Renewal

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-01-04

    ... Office of the Secretary Glen Canyon Dam Adaptive Management Work Group; Notice of Renewal This notice is... of the Interior (Secretary) is renewing the Glen Canyon Dam adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and provide recommendations to the...

  16. Comparison of a two-dimensional adaptive-wall technique with analytical wall interference correction techniques

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1992-01-01

    A two dimensional airfoil model was tested in the adaptive wall test section of the NASA Langley 0.3 meter Transonic Cryogenic Tunnel (TCT) and in the ventilated test section of the National Aeronautical Establishment Two Dimensional High Reynold Number Facility (HRNF). The primary goal of the tests was to compare different techniques (adaptive test section walls and classical, analytical corrections) to account for wall interference. Tests were conducted over a Mach number range from 0.3 to 0.8 at chord Reynolds numbers of 10 x 10(exp 6), 15 x 10(exp 6), and 20 x 10(exp 6). The angle of attack was varied from about 12 degrees up to stall. Movement of the top and bottom test section walls was used to account for the wall interference in the HRNF tests. The test results are in good agreement.

  17. Managing Climate Risk. Integrating Adaptation into World Bank Group Operations

    SciTech Connect

    Van Aalst, M.

    2006-08-15

    Climate change is already taking place, and further changes are inevitable. Developing countries, and particularly the poorest people in these countries, are most at risk. The impacts result not only from gradual changes in temperature and sea level but also, in particular, from increased climate variability and extremes, including more intense floods, droughts, and storms. These changes are already having major impacts on the economic performance of developing countries and on the lives and livelihoods of millions of poor people around the world. Climate change thus directly affects the World Bank Group's mission of eradicating poverty. It also puts at risk many projects in a wide range of sectors, including infrastructure, agriculture, human health, water resources, and environment. The risks include physical threats to the investments, potential underperformance, and the possibility that projects will indirectly contribute to rising vulnerability by, for example, triggering investment and settlement in high-risk areas. The way to address these concerns is not to separate climate change adaptation from other priorities but to integrate comprehensive climate risk management into development planning, programs, and projects. While there is a great need to heighten awareness of climate risk in Bank work, a large body of experience on climate risk management is already available, in analytical work, in country dialogues, and in a growing number of investment projects. This operational experience highlights the general ingredients for successful integration of climate risk management into the mainstream development agenda: getting the right sectoral departments and senior policy makers involved; incorporating risk management into economic planning; engaging a wide range of nongovernmental actors (businesses, nongovernmental organizations, communities, and so on); giving attention to regulatory issues; and choosing strategies that will pay off immediately under current

  18. Highly adaptive tests for group differences in brain functional connectivity.

    PubMed

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that "there is currently no unique solution, but a spectrum of related methods and analytical strategies" to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not only

  19. Highly adaptive tests for group differences in brain functional connectivity

    PubMed Central

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that “there is currently no unique solution, but a spectrum of related methods and analytical strategies” to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not

  20. Black Oral Art Forms: Guided Group Interaction Techniques.

    ERIC Educational Resources Information Center

    Toldson, Ivory L.; Pasteur, Alfred B.

    1981-01-01

    Describes how oral art can positively influence the development of Black people through therapeutic guidance. Group techniques are suggested to stimulate the counselor's creative potential and enhance clients' self-worth Presents guidelines to enhance educational achievement and school retention, and develop determination and persistence. (JAC)

  1. Radar Range Sidelobe Reduction Using Adaptive Pulse Compression Technique

    NASA Technical Reports Server (NTRS)

    Li, Lihua; Coon, Michael; McLinden, Matthew

    2013-01-01

    Pulse compression has been widely used in radars so that low-power, long RF pulses can be transmitted, rather than a highpower short pulse. Pulse compression radars offer a number of advantages over high-power short pulsed radars, such as no need of high-power RF circuitry, no need of high-voltage electronics, compact size and light weight, better range resolution, and better reliability. However, range sidelobe associated with pulse compression has prevented the use of this technique on spaceborne radars since surface returns detected by range sidelobes may mask the returns from a nearby weak cloud or precipitation particles. Research on adaptive pulse compression was carried out utilizing a field-programmable gate array (FPGA) waveform generation board and a radar transceiver simulator. The results have shown significant improvements in pulse compression sidelobe performance. Microwave and millimeter-wave radars present many technological challenges for Earth and planetary science applications. The traditional tube-based radars use high-voltage power supply/modulators and high-power RF transmitters; therefore, these radars usually have large size, heavy weight, and reliability issues for space and airborne platforms. Pulse compression technology has provided a path toward meeting many of these radar challenges. Recent advances in digital waveform generation, digital receivers, and solid-state power amplifiers have opened a new era for applying pulse compression to the development of compact and high-performance airborne and spaceborne remote sensing radars. The primary objective of this innovative effort is to develop and test a new pulse compression technique to achieve ultrarange sidelobes so that this technique can be applied to spaceborne, airborne, and ground-based remote sensing radars to meet future science requirements. By using digital waveform generation, digital receiver, and solid-state power amplifier technologies, this improved pulse compression

  2. How to use the nominal group and Delphi techniques.

    PubMed

    McMillan, Sara S; King, Michelle; Tully, Mary P

    2016-06-01

    Introduction The Nominal Group Technique (NGT) and Delphi Technique are consensus methods used in research that is directed at problem-solving, idea-generation, or determining priorities. While consensus methods are commonly used in health services literature, few studies in pharmacy practice use these methods. This paper provides an overview of the NGT and Delphi technique, including the steps involved and the types of research questions best suited to each method, with examples from the pharmacy literature. Methodology The NGT entails face-to-face discussion in small groups, and provides a prompt result for researchers. The classic NGT involves four key stages: silent generation, round robin, clarification and voting (ranking). Variations have occurred in relation to generating ideas, and how 'consensus' is obtained from participants. The Delphi technique uses a multistage self-completed questionnaire with individual feedback, to determine consensus from a larger group of 'experts.' Questionnaires have been mailed, or more recently, e-mailed to participants. When to use The NGT has been used to explore consumer and stakeholder views, while the Delphi technique is commonly used to develop guidelines with health professionals. Method choice is influenced by various factors, including the research question, the perception of consensus required, and associated practicalities such as time and geography. Limitations The NGT requires participants to personally attend a meeting. This may prove difficult to organise and geography may limit attendance. The Delphi technique can take weeks or months to conclude, especially if multiple rounds are required, and may be complex for lay people to complete.

  3. Adaptive vs. group sequential self-designing trials.

    PubMed

    Mehrotra, Devan V; Fan, Xiaoyin

    2006-08-01

    This is a discussion of the paper. 'Repeated Confidence Intervals in Self-Designing Clinical Trials and Switching between Non-Inferiority and Superinferiority' by Joachim Hartung and Guido Knapp, appearing in this special issue on adaptive designs.

  4. Decisions from Experience: How Groups and Individuals Adapt to Change

    DTIC Science & Technology

    2014-01-01

    Recency , then, may have helped individuals adapt to changes. Although recency effects are a common finding in the context of decisions from...decision-making behavior shows recency effects , as is commonly observed in the literature, individuals can be expected to deviate from Bayesian...Betsch, et al., in press, refer to as routine effects ). Alternatively, they may deviate from Bayesian updating in two ways: They may delay adaptation

  5. Baseline Adaptive Wavelet Thresholding Technique for sEMG Denoising

    NASA Astrophysics Data System (ADS)

    Bartolomeo, L.; Zecca, M.; Sessa, S.; Lin, Z.; Mukaeda, Y.; Ishii, H.; Takanishi, Atsuo

    2011-06-01

    The surface Electromyography (sEMG) signal is affected by different sources of noises: current technology is considerably robust to the interferences of the power line or the cable motion artifacts, but still there are many limitations with the baseline and the movement artifact noise. In particular, these sources have frequency spectra that include also the low-frequency components of the sEMG frequency spectrum; therefore, a standard all-bandwidth filtering could alter important information. The Wavelet denoising method has been demonstrated to be a powerful solution in processing white Gaussian noise in biological signals. In this paper we introduce a new technique for the denoising of the sEMG signal: by using the baseline of the signal before the task, we estimate the thresholds to apply to the Wavelet thresholding procedure. The experiments have been performed on ten healthy subjects, by placing the electrodes on the Extensor Carpi Ulnaris and Triceps Brachii on right upper and lower arms, and performing a flexion and extension of the right wrist. An Inertial Measurement Unit, developed in our group, has been used to recognize the movements of the hands to segment the exercise and the pre-task baseline. Finally, we show better performances of the proposed method in term of noise cancellation and distortion of the signal, quantified by a new suggested indicator of denoising quality, compared to the standard Donoho technique.

  6. Influence of restorative techniques on marginal adaptation and dye penetration around Class V restorations.

    PubMed

    Pereira, Adriana de Fatima Vasconcelos; Poiate, Isis Andrea Venturini Pola; Poiate, Edgar; Rodrigues, Flavia Pires; Turbino, Mirian Lacalle; Miranda, Walter Gomes

    2012-01-01

    The aim of this study was to observe the influence of restorative techniques on marginal adaptation and dye penetration around Class V restorations simulating abfraction lesions. Sixty mandibular premolars were divided into six groups (n = 10) using different restorative materials. Cavity preparation presented the gingival wall localized in dentin and the incisal wall in enamel. Replicas of abfraction lesions were obtained and viewed under a stereomicroscope for adaptation assessment. All teeth were subjected to thermocycling and mechanical load cycling and immersed in 0.5% methylene blue dye (pH 7.2) for four hours. The results were tabulated and submitted to Kruskal-Wallis tests, which were significant for the dentin margin with lower microleakage values for primer/Vitremer, followed by Clearfil SE Bond/Durafill VS and Clearfil SE Bond/Z100 in qualitative and quantitative methods (P < 0.05). The enamel margin had no significant difference for microleakage values for all groups. There was no statistically significant difference among the substrates for marginal adaptation. The Spearman coefficient illustrated a direct relation between enamel and dentin for microleakage evaluation (P < 0.0001). The data demonstrated no difference for marginal fit by chi-square test. It can be concluded that all groups had microleakage in different degrees, with the lowest values for resin-modified glass ionomer.

  7. Influence of a proximal margin elevation technique on marginal adaptation of ceramic inlays.

    PubMed

    Zaruba, M; Göhring, T N; Wegehaupt, F J; Attin, T

    2013-03-01

    Evaluating the effect of a proximal margin elevation technique on marginal adaptation of ceramic inlays. Class II MOD-cavities were prepared in 40 human molars and randomly distributed to four groups (n = 10). In group EN (positive control) proximal margins were located in enamel, 1 mm above the cementoenamel junction, while 2 mm below in groups DE-1In, DE-2In and DE. The groups DE-1In, DE-2In and DE simulated subgingival location of the cervical margin. In group DE-1In one 3 mm and in group DE-2In two 1.5 mm composite layers (Tetric) were placed for margin elevation of the proximal cavities using Syntac classic as an adhesive. The proximal cavities of group DE remained untreated and served as a negative control. In all groups, ceramic inlays (Cerec 3D) were adhesively inserted. Replicas were taken before and after thermomechanical loading (1.200.000 cycles, 50/5°C, max. load 49 N). Marginal integrity (tooth-composite, composite-inlay) was evaluated with scanning electron microscopy (200×). Percentage of continuous margin (% of total proximal margin length) was compared between groups before and after cycling using ANOVA and Scheffé post-hoc test. After thermomechanical loading, no significant differences were observed between the different groups with respect to the interface composite-inlay and tooth-composite with margins in dentin. The interface tooth-composite in enamel of group EN was significantly better compared to group DE-2In, which was not different to the negative control group DE and DE-1In. Margin elevation technique by placement of a composite filling in the proximal box before insertion of a ceramic inlay results in marginal integrities not different from margins of ceramic inlays placed in dentin.

  8. 65 FR 69787 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-11-20

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG); Correction AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of Public Meetings... Group (AMWG) and Glen Canyon Technical Work Group (TWG). The document contained incorrect dates....

  9. 75 FR 439 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... Work Group (AMWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY... Federal advisory committee, the Adaptive Management Work Group (AMWG), a Technical Work Group (TWG), a...

  10. [Relapse prevention group therapy for paedophiles: French adaptation].

    PubMed

    Smith, J; Petibon, C

    2005-01-01

    Psychotherapy for sex offenders has only very recently started to develop in France. The French law on compulsory treatment for sex offenders was voted in 1998, and many mental health practitioners are not trained to treat such patients yet. In our ambulatory forensic consultation, sex offenders have been treated since 1992 and group psychotherapy has been offered to them since 1994. Our first therapeutic models were the North-American behavioural-cognitive therapy and Pithers' relapse prevention model. Behavioural-cognitive theory describes paedophilia as an acquired sexual preference maintained by positive reinforcement. Pithers (1990) considered that relapse only occurs in high-risk situations, and that high-risk situations always come after offence precursors. In North America, relapse prevention consists in helping paedophiles spot their high-risk situations and offence precursors, and enhance their skills to cope with such situations or to prevent them. Therapy programs were developed according to these models, aiming to help offenders develop such skills, ie empathy, social skills, cognitive restructuring, self-esteem, etc. Trying to apply these therapy programs in France, our team quickly realised that we would have to adapt them to French culture. On the one hand, behavioural-cognitive theory did not seem satisfactory enough in explaining paedophilic behaviour and paedophilic preference. On the other hand, behavioural-cognitive therapy made patients into children too much and increased resistance. Therapy based on programs seemed too rigid for French patients and therapists, and we often felt we were working on an issue that would have been much more accurate to work on a few sessions earlier, when this issue was spontaneously brought up by a patient. We believe change occurs all the more as issues are worked on at the right moment for the patient. Moreover, on a cultural point of view, we also realised the use of programs in psychotherapy was difficult to

  11. Adaptivity techniques for the computation of two-dimensional viscous flows using structured meshes

    NASA Astrophysics Data System (ADS)

    Szmelter, J.; Evans, A.; Weatherill, N. P.

    In this paper three different adaptivity techniques have been investigated on the base of structured meshes. All the techniques indicate the significance of using adaptivity for improving computational results. In particular, the technique of combining point enrichment and node movement strategies offers the best compromise. Although, the work presented here used two-dimensional structured meshes, the techniques can be readily applied to hybrid and unstructured meshes. Also, preliminary three-dimensional numerical results have been already obtained by coauthors.

  12. Model-reference adaptive control system design technique

    NASA Technical Reports Server (NTRS)

    Sutherlin, D. W.; Boland, J. S., III

    1973-01-01

    This paper considers the model-reference adaptive control problem which has received considerable attention in the literature in the last few years. An adaptive control scheme is proposed which has terms in the Liapunov function used in the design procedure which are not included in previously proposed schemes. The relationship of this new scheme to existing schemes is shown by considering the root-loci of the linearized error equations between plant and model. Finally, a second order example is given which illustrates the difference between the two previously proposed model-reference adaptive methods and the one proposed in this paper.

  13. 74 FR 36505 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2009-07-23

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation.... L. 102-575) of 1992. The AMP includes a federal advisory committee, the Adaptive Management Work Group (AMWG), a technical work group (TWG), a Grand Canyon Monitoring and Research Center,...

  14. 74 FR 16009 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2009-04-08

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation... 1992. The AMP includes a federal advisory committee (AMWG), a technical work group (TWG), a monitoring... . Dated: March 19, 2009. Dennis Kubly, Chief, Adaptive Management Group, Environmental Resources...

  15. A Space/Fast-Time Adaptive Monopulse Technique

    NASA Astrophysics Data System (ADS)

    Seliktar, Yaron; Williams, Douglas B.; Holder, E. Jeff

    2006-12-01

    Mainbeam jamming poses a particularly difficult challenge for conventional monopulse radars. In such cases spatially adaptive processing provides some interference suppression when the target and jammer are not exactly coaligned. However, as the target angle approaches that of the jammer, mitigation performance is increasingly hampered and distortions are introduced into the resulting beam pattern. Both of these factors limit the reliability of a spatially adaptive monopulse processor. The presence of coherent multipath in the form of terrain-scattered interference (TSI), although normally considered a nuisance, can be exploited to suppress mainbeam jamming with space/fast-time processing. A method is presented offering space/fast-time monopulse processing with distortionless spatial array patterns that can achieve improved angle estimation over spatially adaptive monopulse. Performance results for the monopulse processor are obtained for mountaintop data containing a jammer and TSI, which demonstrate a dramatic improvement in performance over conventional monopulse and spatially adaptive monopulse.

  16. Techniques for radar imaging using a wideband adaptive array

    NASA Astrophysics Data System (ADS)

    Curry, Mark Andrew

    A microwave imaging approach is simulated and validated experimentally that uses a small, wideband adaptive array. The experimental 12-element linear array and microwave receiver uses stepped frequency CW signals from 2--3 GHz and receives backscattered energy from short range objects in a +/-90° field of view. Discone antenna elements are used due to their wide temporal bandwidth, isotropic azimuth beam pattern and fixed phase center. It is also shown that these antennas have very low mutual coupling, which significantly reduces the calibration requirements. The MUSIC spectrum is used as a calibration tool. Spatial resampling is used to correct the dispersion effects, which if not compensated causes severe reduction in detection and resolution for medium and large off-axis angles. Fourier processing provides range resolution and the minimum variance spectral estimate is employed to resolve constant range targets for improved angular resolution. Spatial smoothing techniques are used to generate signal plus interference covariance matrices at each range bin. Clutter affects the angular resolution of the array due to the increase in rank of the signal plus clutter covariance matrix, whereas at the same time the rank of this matrix is reduced for closely spaced scatterers due to signal coherence. A method is proposed to enhance angular resolution in the presence of clutter by an approximate signal subspace projection (ASSP) that maps the received signal space to a lower effective rank approximation. This projection operator has a scalar control parameter that is a function of the signal and clutter amplitude estimates. These operations are accomplished without using eigendecomposition. The low sidelobe levels allow the imaging of the integrated backscattering from the absorber cones in the chamber. This creates a fairly large clutter signature for testing ASSP. We can easily resolve 2 dihedrals placed at about 70% of a beamwidth apart, with a signal to clutter ratio

  17. Employment of Adaptive Learning Techniques for the Discrimination of Acoustic Emissions.

    DTIC Science & Technology

    1983-11-01

    8D-1Ai38 142 EMPLOYMENT OP ADAPTIVE LEARNING TECHNIQUES FOR THE I DISCRIMINATION OF ACOU..(U) GENERAL ELECTRIC CORPORATE U Ch, RESEARCH AND...OFSTNDRD-96- 1.5%. 111 11 :%____ 111. %I1~.~ 11 1 - 111 -- k. -Jr -. P. -L -. b. EMPLOYMENT OF ADAPTIVE LEARNING TECHNIQUESEli FOR THE DISCRIMINATION OF...8217Include Security Claaaaficatiano Employment of Adaptive * Learning Techniques for the Discrimination Of Acoustic Emissions (Unclassified) 12.’ PE SNAU.R S

  18. Curriculum revision: reaching faculty consensus through the Nominal Group Technique.

    PubMed

    Davis, D C; Rhodes, R; Baker, A S

    1998-10-01

    A fundamental concept to initiate change in the curriculum revision process is to overcome resistance to change and the boundaries of self-interest. Curriculum change cannot occur without an "unfreezing" of faculty values and interests. The Nominal Group Technique (NGT) was used to facilitate faculty identification of areas needing change in the undergraduate nursing curriculum. The process led to the generation of numerous independent ideas in which all faculty participated. The revised curriculum which resulted from the NGT process has had full and enthusiastic support of the faculty.

  19. Comparative regulatory approaches for groups of new plant breeding techniques.

    PubMed

    Lusser, Maria; Davies, Howard V

    2013-06-25

    This manuscript provides insights into ongoing debates on the regulatory issues surrounding groups of biotechnology-driven 'New Plant Breeding Techniques' (NPBTs). It presents the outcomes of preliminary discussions and in some cases the initial decisions taken by regulators in the following countries: Argentina, Australia, Canada, EU, Japan, South Africa and USA. In the light of these discussions we suggest in this manuscript a structured approach to make the evaluation more consistent and efficient. The issue appears to be complex as these groups of new technologies vary widely in both the technologies deployed and their impact on heritable changes in the plant genome. An added complication is that the legislation, definitions and regulatory approaches for biotechnology-derived crops differ significantly between these countries. There are therefore concerns that this situation will lead to non-harmonised regulatory approaches and asynchronous development and marketing of such crops resulting in trade disruptions.

  20. 65 FR 70735 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon; Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-11-27

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon; Technical Work... has been organized and includes a federal advisory committee (the AMWG), a technical work group (the... AND LOCATION: The Glen Canyon Technical Work Group will conduct the following public meetings:...

  1. 64 FR 25905 - Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-05-13

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meetings. SUMMARY: The Glen Canyon Technical Work Group was formed as an official subcommittee of the Glen Canyon...

  2. 64 FR 61122 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG...

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-11-09

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG); Correction AGENCY: Bureau of Reclamation, Interior. ACTION: Notice; correction. SUMMARY..., concerning the announcement of an upcoming public meeting of the Glen Canyon Technical Work Group....

  3. 65 FR 79122 - Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2000-12-18

    ... Bureau of Reclamation Glen Canyon Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work... has been organized and includes a federal advisory committee (the AMWG), a technical work group (the... and Location: The Glen Canyon Technical Work Group will conduct the following public meetings:...

  4. 66 FR 34240 - Glen Canyon Dam Adaptive Management Work Group (AMWG), and Glen Canyon Technical Work Group (TWG...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2001-06-27

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG), and Glen Canyon Technical Work Group (TWG); Cancellation of Meetings AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of... Work Group Meeting Scheduled for July 17-18, 2001, in Phoenix, Arizona, in order to complete work...

  5. Techniques for grid manipulation and adaptation. [computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Choo, Yung K.; Eisemann, Peter R.; Lee, Ki D.

    1992-01-01

    Two approaches have been taken to provide systematic grid manipulation for improved grid quality. One is the control point form (CPF) of algebraic grid generation. It provides explicit control of the physical grid shape and grid spacing through the movement of the control points. It works well in the interactive computer graphics environment and hence can be a good candidate for integration with other emerging technologies. The other approach is grid adaptation using a numerical mapping between the physical space and a parametric space. Grid adaptation is achieved by modifying the mapping functions through the effects of grid control sources. The adaptation process can be repeated in a cyclic manner if satisfactory results are not achieved after a single application.

  6. Techniques for grid manipulation and adaptation. [computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Choo, Yung K.; Eisemann, Peter R.; Lee, Ki D.

    1992-01-01

    Two approaches have been taken to provide systematic grid manipulation for improved grid quality. One is the control point form (CPF) of algebraic grid generation. It provides explicit control of the physical grid shape and grid spacing through the movement of the control points. It works well in the interactive computer graphics environment and hence can be a good candidate for integration with other emerging technologies. The other approach is grid adaptation using a numerical mapping between the physical space and a parametric space. Grid adaptation is achieved by modifying the mapping functions through the effects of grid control sources. The adaptation process can be repeated in a cyclic manner if satisfactory results are not achieved after a single application.

  7. Beaconless adaptive-optics technique for HEL beam control

    NASA Astrophysics Data System (ADS)

    Khizhnyak, Anatoliy; Markov, Vladimir

    2016-05-01

    Effective performance of forthcoming laser systems capable of power delivery on a distant target requires an adaptive optics system to correct atmospheric perturbations on the laser beam. The turbulence-induced effects are responsible for beam wobbling, wandering, and intensity scintillation, resulting in degradation of the beam quality and power density on the target. Adaptive optics methods are used to compensate for these negative effects. In its turn, operation of the AOS system requires a reference wave that can be generated by the beacon on the target. This report discusses a beaconless approach for wavefront correction with its performance based on the detection of the target-scattered light. Postprocessing of the beacon-generated light field enables retrieval and detailed characterization of the turbulence-perturbed wavefront -data that is essential to control the adaptive optics module of a high-power laser system.

  8. A new optimization technique for adaptive antenna arrays

    NASA Astrophysics Data System (ADS)

    Ohnishi, Katsumi; Milton, Robert T.

    1993-05-01

    This paper describes a new adaptive nulling algorithm for adjusting the array weights under the 'soft' constraint based on the measured correlations between the array and element outputs. The algorithm can be regarded as an extension of the constrained LMS algorithm. The present algorithm is derived from the same concept of signal and noise subspaces defined in the well-known MUSIC algorithm. One of the unique features of the present algorithm is that the number of the iterations required to adapt the array weights to form nulls is exactly equal to the number of interferers.

  9. Industrial OCR approaches: architecture, algorithms, and adaptation techniques

    NASA Astrophysics Data System (ADS)

    Marosi, István

    2007-01-01

    Optical Character Recognition is much more than character classification. An industrial OCR application combines algorithms studied in detail by different researchers in the area of image processing, pattern recognition, machine learning, language analysis, document understanding, data mining, and other, artificial intelligence domains. There is no single perfect algorithm for any of the OCR problems, so modern systems try to adapt themselves to the actual features of the image or document to be recognized. This paper describes the architecture of a modern OCR system with an emphasis on this adaptation process.

  10. Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

    SciTech Connect

    Asher, R.B.; Cameron, S.M.; Loubriel, G.M.; Robinett, R.D.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1998-11-25

    In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical "and difficult to characterize. An alternative approach is to implement an adap- tively deployable array of sensitive agent-specific devices. Our group has been studying the collective be- havior of an autonomous, multi-agent system applied to chedbio detection and related emerging threat applications, The current physics-based models we are using coordinate a sensor array for mukivanate sig- nal optimization and coverage as re,alized by a swarm of robots or mobile vehicles. These intelligent control systems integrate'glob"ally operating decision-making systems and locally cooperative learning neural net- works to enhance re+-timp operational responses to dynarnical environments examples of which include obstacle avoidance, res~onding to prevailing wind patterns, and overcoming other natural obscurants or in- terferences. Collectively',tkensor nefirons with simple properties, interacting according to basic community rules, can accomplish complex interconnecting functions such as generalization, error correction, pattern recognition, sensor fusion, and localization. Neural nets provide a greater degree of robusmess and fault tolerance than conventional systems in that minor variations or imperfections do not impair performance. The robotic platforms would be equipped with sensor devices that perform opticaI detection of biologicais in combination with multivariate chemical analysis tools based on genetic and neural network algorithms, laser-diode LIDAR analysis, ultra-wideband short-pulsed transmitting and receiving antennas, thermal im- a:ing sensors, and optical Communication technology providing robust data throughput pathways. Mission scenarios under consideration include ground penetrating radar (GPR) for detection of underground struc- tures, airborne systems, and plume migration and mitigation. We will describe our research in

  11. Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

    SciTech Connect

    Cameron, S.M.; Loubriel, G.M.; Rbinett, R.D. III; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1999-04-01

    This paper focuses on our recent work at Sandia National Laboratories toward engineering a physics-based swarm of mobile vehicles for distributed sensing applications. Our goal is to coordinate a sensor array that optimizes sensor coverage and multivariate signal analysis by implementing artificial intelligence and evolutionary computational techniques. These intelligent control systems integrate both globally operating decision-making systems and locally cooperative information-sharing modes using genetically-trained neural networks. Once trained, neural networks have the ability to enhance real-time operational responses to dynamical environments, such as obstacle avoidance, responding to prevailing wind patterns, and overcoming other natural obscurants or interferences (jammers). The swarm realizes a collective set of sensor neurons with simple properties incorporating interactions based on basic community rules (potential fields) and complex interconnecting functions based on various neural network architectures, Therefore, the swarm is capable of redundant heterogeneous measurements which furnishes an additional degree of robustness and fault tolerance not afforded by conventional systems, while accomplishing such cognitive tasks as generalization, error correction, pattern recognition, and sensor fission. The robotic platforms could be equipped with specialized sensor devices including transmit/receive dipole antennas, chemical or biological sniffers in combination with recognition analysis tools, communication modulators, and laser diodes. Our group has been studying the collective behavior of an autonomous, multi-agent system applied to emerging threat applications. To accomplish such tasks, research in the fields of robotics, sensor technology, and swarms are being conducted within an integrated program. Mission scenarios under consideration include ground penetrating impulse radar (GPR) for detection of under-ground structures, airborne systems, and plume

  12. Group Theoretical Techniques in Analyzing Vibronic Spectra from Doped Crystals.

    NASA Astrophysics Data System (ADS)

    Aproberts-Warren, Nicholas; Collins, John

    2007-04-01

    In this work we consider the use of vibronic spectra of rare earth and transition metal ions in ionic crystals to gain information on the phonon density of states. The impurity ion destroys the translational symmetry, leading to vibronic sidebands to emission lines that resemble the density of states. We focus on the application of selection rules for vibronic transitions to select crystals. Using group theoretical techniques, the symmetry of a crystal's unit cell and Brillouin Zone lead to ``irreducible representations'' of the space group of the crystal. Each of these representations corresponds to specific phonon modes of the perfect crystal. To determine which phonon modes can interact with the ion, the space group representations are reduced in terms of the site symmetry of the impurity, after which the selection rules can be applied. The specific case of Vn^2+ in MgO is examined, and the results are compared with neutron scattering, Raman, and infrared data. Selection rules are also found for the cases of Cr^3+ in strontium titanate and in yttrium aluminum garnet. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.B1.5

  13. 77 FR 60138 - Trinity Adaptive Management Working Group; Public Teleconference/Web-Based Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-02

    ... Fish and Wildlife Service Trinity Adaptive Management Working Group; Public Teleconference/ Web-Based... Wildlife Service, announce a public teleconference/web-based meeting of ] the Trinity Adaptive Management Working Group (TAMWG). DATES: Teleconference/web-based meeting: Wednesday October 17, 2012, from 9 a.m. to...

  14. 76 FR 4365 - Renewal of the Trinity River Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ... Office of the Secretary Renewal of the Trinity River Adaptive Management Working Group AGENCY: Office of... Working Group (Working Group) for 2 years. The Working Group provides recommendations on all aspects of...; 707-822-7201. SUPPLEMENTARY INFORMATION: The Working Group conducts its operations in accordance...

  15. Adaptive parameter blind source separation technique for wheel condition monitoring

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Gao, Hongli; Liu, Qiyue; Farzadpour, F.; Grebe, C.; Tian, Ying

    2017-06-01

    Wheel condition monitoring has played a key role in the safe operation of railway vehicles. Blind source separation (BSS) is an attractive tool due to its excellent performance in separating source signals from their mixtures when no detailed knowledge of defective sources and the mixing process is assumed. In this paper, we propose an adaptive parameter BSS approach based on the adaptive time-frequency distributions theory in order to deal with the non-stationary blind separation problem and apply it to wheel defect monitoring. Some classical time-frequency signal analysis and BSS methods are applied in comparison with the proposed approach through frequency-varying non-stationary and time-varying non-stationary simulations. Experiments of single and multi-fault wheels have been conducted using the wheel/rail simulation facility to illustrate the effectiveness of the proposed method in processing the non-stationary signals with varying fault complexity.

  16. Adaptive Techniques for Control of Large Space Structures.

    DTIC Science & Technology

    1984-12-01

    S1 a ) remais oiniall teruine the robt imss propertie% of adaptive stable. 1 hts. h\\ iheoi-cin 2. an) -regionl of local algorithms Ni oreose, . input...that Vg¢R ev + .[Hev(Jw)] 4 y and 1 He(iw) + Hey • ’I (4.8a) Then, bounds on lei 2 and 1o. can be obtained from: le-e~2 1 112*2 l~ 2 ’eo 12 [ie.* 2

  17. 63 FR 70421 - Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    1998-12-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) and Glen Canyon Technical Work Group (TWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of Public Meetings;...

  18. Scientific Motivational Techniques Adaptable to Social Studies Lessons

    ERIC Educational Resources Information Center

    Steiner, Robert L.

    1975-01-01

    Two science classroom techniques that can be used in the social studies classroom to motivate students involve puzzling phenomena and relating science to social issues such as over-population, energy, and pollution. (JR)

  19. Scientific Motivational Techniques Adaptable to Social Studies Lessons

    ERIC Educational Resources Information Center

    Steiner, Robert L.

    1975-01-01

    Two science classroom techniques that can be used in the social studies classroom to motivate students involve puzzling phenomena and relating science to social issues such as over-population, energy, and pollution. (JR)

  20. Experience Report Summary: Applying Adaptive Safety Analysis Techniques

    NASA Technical Reports Server (NTRS)

    Lutz, R.; Shaw, H-Y.

    1999-01-01

    Current needs for high-reliability, reusable software; rapid, evolutionary development; and verification of innovative software architectures have focused attention on improving techniques for analyzing the safety and reliability of embedded software.

  1. Full symmetry implementation in condensed matter and molecular physics-Modified group projector technique

    NASA Astrophysics Data System (ADS)

    Damnjanović, Milan; Milošević, Ivanka

    2015-06-01

    Symmetry is well established as one of the fundamental concepts in physics, accurately extracting relevant characteristics of the studied object, giving deep and transparent insight to its properties. In the solid state and molecular physics the most abundant application is reduction of the dimension of the eigenproblem of the Hamiltonian, with the resulting eigenvectors labeled by good quantum numbers, forming the so called symmetry adapted basis. Such a basis is the starting point for subsequent analysis of the physical properties of the system, performed usually by applying adequate perturbation technique. Standard procedure for finding a symmetry adapted basis involves Wigner operators, which are sums of the operators acting in the quantum state space (Hilbert space, most usually) over all elements of the symmetry group of the systems. However, both the dimension of the state space and the number of the symmetry transformations are infinite even in the simplest approximate models in crystal physics making obstacles for direct application of the standard Wigner projector technique, and its numerical implementation. On the other hand, there is a minimal part of the system, the full symmetry elementary cell (symcell), from which the whole system can be built by action of the full symmetry group elements on it. A clear heuristic idea, that symcell and full symmetry group, determine the properties of the entire system, is fully realized within modified group projector technique. Namely, when applying this technique, the full symmetry of the system is used to provide reduction of calculations to the symcell only, singling out its state space (of a finite dimension!) as the effective state space to be worked in. Physical observables, expressed through their irreducible tensor components, obtain their counterparts in this finite-dimensional space of a symcell. It remains to consider only the symmetry transformations which leave the symcell invariant. This is absolutely

  2. Adaptive awareness for personal and small group decision making.

    SciTech Connect

    Perano, Kenneth J.; Tucker, Steve; Pancerella, Carmen M.; Doser, Adele Beatrice; Berry, Nina M.; Kyker, Ronald D.

    2003-12-01

    Many situations call for the use of sensors monitoring physiological and environmental data. In order to use the large amounts of sensor data to affect decision making, we are coupling heterogeneous sensors with small, light-weight processors, other powerful computers, wireless communications, and embedded intelligent software. The result is an adaptive awareness and warning tool, which provides both situation awareness and personal awareness to individuals and teams. Central to this tool is a sensor-independent architecture, which combines both software agents and a reusable core software framework that manages the available hardware resources and provides services to the agents. Agents can recognize cues from the data, warn humans about situations, and act as decision-making aids. Within the agents, self-organizing maps (SOMs) are used to process physiological data in order to provide personal awareness. We have employed a novel clustering algorithm to train the SOM to discern individual body states and activities. This awareness tool has broad applicability to emergency teams, military squads, military medics, individual exercise and fitness monitoring, health monitoring for sick and elderly persons, and environmental monitoring in public places. This report discusses our hardware decisions, software framework, and a pilot awareness tool, which has been developed at Sandia National Laboratories.

  3. Evaluation of internal adaptation in ceramic and composite resin inlays by silicon replica technique.

    PubMed

    Karakaya, S; Sengun, A; Ozer, F

    2005-06-01

    This study was aimed at investigating the internal adaptation of a ceramic (Ceramco II) and two composite resin inlay materials (SureFil and 3M Filtek Z 250) using silicon replica technique as an indicator. Forty-five standard mesial-occlusal-distal (MOD) cavities were prepared into brass moulds by using computer numerically controlled system. Inlays were prepared according to manufacturers' instructions with indirect methods. Replicas of the prepared cavities and inlays were produced with a polyvinyl siloxane material (Elite H-D). The spaces between inlays and cavities were filled by different coloured light-body polyvinyl siloxane material. Two parallel slices (mesio-distally) were obtained from the replicas with a sharp blade. Different coloured polyvinyl siloxane material thickness between cavity and inlay was measured at seven points (mesial, occlusal and distal). The data were evaluated with anova and Tukey's honestly significantly different (HSD) statistical tests. In the SureFil and Ceramco II groups, the sizes of the contraction gaps at mesial and distal gingival floors were greater than that of the occlusal marginal walls. In comparison of gap formation at occlusal regions, while the 3M composite group showed highest gap values (204.33 +/- 75.45 microm), the Ceramco II group revealed the lowest (141.17 +/- 23.66 microm) (P < 0.05). At the gingival floors, gap formation of Ceramco II group was the highest (227.08 +/- 51.95 microm). Neither the 3M Filtek Z250 nor SureFil group showed any statistical difference between gap values of their self-occlusal and gingival floors (P > 0.05). In conclusion, our results showed that ceramic inlays did not confer any big advantage for internal adaptation over the composite inlays.

  4. Swarm Intelligence: New Techniques for Adaptive Systems to Provide Learning Support

    ERIC Educational Resources Information Center

    Wong, Lung-Hsiang; Looi, Chee-Kit

    2012-01-01

    The notion of a system adapting itself to provide support for learning has always been an important issue of research for technology-enabled learning. One approach to provide adaptivity is to use social navigation approaches and techniques which involve analysing data of what was previously selected by a cluster of users or what worked for…

  5. Multi-Attribute Utility Theory and Adaptive Techniques for Intelligent Web-Based Educational Software

    ERIC Educational Resources Information Center

    Kabassi, K.; Virvou, M.

    2006-01-01

    This paper describes how the Multi-Attribute Utility Theory can be combined with adaptive techniques to improve individualised teaching in an Intelligent Learning Environment (ILE). The ILE is called Web F-SMILE, it operates over the Web and is meant to help novice users learn basic skills of computer use. Tutoring is dynamically adapted to the…

  6. Swarm Intelligence: New Techniques for Adaptive Systems to Provide Learning Support

    ERIC Educational Resources Information Center

    Wong, Lung-Hsiang; Looi, Chee-Kit

    2012-01-01

    The notion of a system adapting itself to provide support for learning has always been an important issue of research for technology-enabled learning. One approach to provide adaptivity is to use social navigation approaches and techniques which involve analysing data of what was previously selected by a cluster of users or what worked for…

  7. Monaural loudness adaptation for middle-intensity middle-frequency signals: the importance of measurement technique.

    PubMed

    Tannen, R S; Weiler, E M; Warm, J S; Dember, W N; Simon, J O

    2001-10-01

    Using the Simple Adaptation technique (SA) and the Ipsilateral Comparison Paradigm (ICP), the authors studied monaural loudness adaptation to a middle-intensity [60 dB(A)] tone at signal frequencies of 250, 1000, and 4000 Hz in the left and right ears. Adaptation effects were absent when the SA procedure was used. However, they were observed uniformly across all frequency values with the ICP, a result that challenges the assertion in the literature, on the basis of SA measures, that loudness adaptation for middle-intensity signals occurs only at frequencies above 4000 Hz. The ICP features periodic intensity modulations (+/-10 dB relative to the base signal) to accommodate listeners' needs for referents by which they can gauge subtle changes in the loudness of the adapting tone, a key component that is missing in the SA method. Adaptation effects in this investigation were similar in both ears, supporting the equal susceptibility assumption common in loudness adaptation studies.

  8. Adaptive Grid Techniques for Elliptic Fluid-Flow Problems,

    DTIC Science & Technology

    1985-12-01

    J . F . (1984), "Grid Generation Techniques in Computational Fluid Dynamics," AIAA Jnl., Vol. 22, No. 11, pp. 1505-1523. Thompson , J . F . (1983...Procedure," Ph.D. Thesis, Dept. of Computer Science, Stanford University, Calif. Tang, W. P., W. Skamarock, and J. Oliger (1985). To appear. Thompson

  9. Develop techniques for ion implantation of PLZT for adaptive optics

    NASA Astrophysics Data System (ADS)

    Craig, R. A.; Batishko, C. R.; Brimhall, J. L.; Pawlewicz, W. T.; Stahl, K. A.

    1989-11-01

    Battelle Pacific Northwest Laboratory (PNL) conducted research into the preparation and characterization of ion-implanted adaptive optic elements based on lead-lanthanum-zirconate-titanate (PLZT). Over the 4-yr effort beginning FY 1985, the ability to increase the photosensitivity of PLZT and extend it to longer wavelengths was developed. The emphasis during the last two years was to develop a model to provide a basis for choosing implantation species and parameters. Experiments which probe the electronic structure were performed on virgin and implanted PLZT samples. Also performed were experiments designed to connect the developing conceptual model with the experimental results. The emphasis in FY 1988 was to extend the photosensitivity out to diode laser wavelengths. The experiments and modelling effort indicate that manganese will form appropriate intermediate energy states to achieve the longer wavelength photosensitivity. Preliminary experiments were also conducted to deposit thin film PLZT.

  10. Assessment of Service Protocols Adaptability Using a Novel Path Computation Technique

    NASA Astrophysics Data System (ADS)

    Zhou, Zhangbing; Bhiri, Sami; Haller, Armin; Zhuge, Hai; Hauswirth, Manfred

    In this paper we propose a new kind of adaptability assessment that determines whether service protocols of a requestor and a provider are adaptable, computes their adaptation degree, and identifies conditions that determine when they can be adapted. We also propose a technique that implements this adaptability assessment: (1) we construct a complete adaptation graph that captures all service interactions adaptable between these two service protocols. The emptiness or non-emptiness of this graph corresponds to the fact that whether or not they are adaptable; (2) we propose a novel path computation technique to generate all instance sub-protocols which reflect valid executions of a particular service protocol, and to derive all instance sub-protocol pairs captured by the complete adaptation graph. An adaptation degree is computed as a ratio between the number of instance sub-protocols captured by these instance sub-protocol pairs with respect to a service protocol and that of this service protocol; (3) and finally we identify a set of conditions based on these instance sub-protocol pairs. A condition is the conjunction of all conditions specified on the transitions of a given pair of instance sub-protocols. This assessment is a comprehensive means of selecting the suitable service protocol among functionally-equivalent candidates according to the requestor's business requirements.

  11. 78 FR 5830 - Renewal of the Trinity River Adaptive Management Working Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ... to give policy, management, and technical input concerning Trinity River restoration efforts. FOR... Office of the Secretary Renewal of the Trinity River Adaptive Management Working Group AGENCY: Office of... consultation with the General Services Administration, has renewed the Trinity River Adaptive...

  12. 78 FR 42799 - Glen Canyon Dam Adaptive Management Work Group Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group Meetings AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work... operations and other management actions to protect resources downstream of Glen Canyon Dam, consistent with...

  13. Time domain and frequency domain design techniques for model reference adaptive control systems

    NASA Technical Reports Server (NTRS)

    Boland, J. S., III

    1971-01-01

    Some problems associated with the design of model-reference adaptive control systems are considered and solutions to these problems are advanced. The stability of the adapted system is a primary consideration in the development of both the time-domain and the frequency-domain design techniques. Consequentially, the use of Liapunov's direct method forms an integral part of the derivation of the design procedures. The application of sensitivity coefficients to the design of model-reference adaptive control systems is considered. An application of the design techniques is also presented.

  14. Three-dimensional adaptive grid-embedding Euler technique

    NASA Astrophysics Data System (ADS)

    Davis, Roger L.; Dannenhoffer, John F., III

    1994-06-01

    A new three-dimensional adaptive-grid Euler procedure is presented that automatically detects high-gradient regions in the flow and locally subdivides the computational grid in these regions to provide a uniform, high level of accuracy over the entire domain. A tunable, semistructured data system is utilized that provides global topological unstructured-grid flexibility along with the efficiency of a local, structured-grid system. In addition, this structure data allows for the flow solution algorithm to be executed on a wide variety of parallel/vector computing platforms. An explicit, time-marching, control volume procedure is used to integrate the Euler equations to a steady state. In addition, a multiple-grid procedure is used throughout the embedded-grid regions as well as on subgrids coarser than the initial grid to accelerate convergence and properly propagate disturbance waves through refined-grid regions. Upon convergence, high flow gradient regions, where it is assumed that large truncation errors in the solution exist, are detected using a combination of directional refinement vectors that have large components in areas of these gradients. The local computational grid is directionally subdivided in these regions and the flow solution is reinitiated. Overall convergence occurs when a prespecified level of accuracy is reached. Solutions are presented that demonstrate the efficiency and accuracy of the present procedure.

  15. Parallel adaptive mesh refinement techniques for plasticity problems

    NASA Technical Reports Server (NTRS)

    Barry, W. J.; Jones, M. T.; Plassmann, P. E.

    1997-01-01

    The accurate modeling of the nonlinear properties of materials can be computationally expensive. Parallel computing offers an attractive way for solving such problems; however, the efficient use of these systems requires the vertical integration of a number of very different software components, we explore the solution of two- and three-dimensional, small-strain plasticity problems. We consider a finite-element formulation of the problem with adaptive refinement of an unstructured mesh to accurately model plastic transition zones. We present a framework for the parallel implementation of such complex algorithms. This framework, using libraries from the SUMAA3d project, allows a user to build a parallel finite-element application without writing any parallel code. To demonstrate the effectiveness of this approach on widely varying parallel architectures, we present experimental results from an IBM SP parallel computer and an ATM-connected network of Sun UltraSparc workstations. The results detail the parallel performance of the computational phases of the application during the process while the material is incrementally loaded.

  16. Parallel adaptive mesh refinement techniques for plasticity problems

    NASA Technical Reports Server (NTRS)

    Barry, W. J.; Jones, M. T.; Plassmann, P. E.

    1997-01-01

    The accurate modeling of the nonlinear properties of materials can be computationally expensive. Parallel computing offers an attractive way for solving such problems; however, the efficient use of these systems requires the vertical integration of a number of very different software components, we explore the solution of two- and three-dimensional, small-strain plasticity problems. We consider a finite-element formulation of the problem with adaptive refinement of an unstructured mesh to accurately model plastic transition zones. We present a framework for the parallel implementation of such complex algorithms. This framework, using libraries from the SUMAA3d project, allows a user to build a parallel finite-element application without writing any parallel code. To demonstrate the effectiveness of this approach on widely varying parallel architectures, we present experimental results from an IBM SP parallel computer and an ATM-connected network of Sun UltraSparc workstations. The results detail the parallel performance of the computational phases of the application during the process while the material is incrementally loaded.

  17. Parallel adaptive mesh refinement techniques for plasticity problems

    SciTech Connect

    Barry, W.J.; Jones, M.T. |; Plassmann, P.E.

    1997-12-31

    The accurate modeling of the nonlinear properties of materials can be computationally expensive. Parallel computing offers an attractive way for solving such problems; however, the efficient use of these systems requires the vertical integration of a number of very different software components, we explore the solution of two- and three-dimensional, small-strain plasticity problems. We consider a finite-element formulation of the problem with adaptive refinement of an unstructured mesh to accurately model plastic transition zones. We present a framework for the parallel implementation of such complex algorithms. This framework, using libraries from the SUMAA3d project, allows a user to build a parallel finite-element application without writing any parallel code. To demonstrate the effectiveness of this approach on widely varying parallel architectures, we present experimental results from an IBM SP parallel computer and an ATM-connected network of Sun UltraSparc workstations. The results detail the parallel performance of the computational phases of the application during the process while the material is incrementally loaded.

  18. Descriptive Feedback; Increasing Teacher Awareness, Adapting Research Techniques.

    ERIC Educational Resources Information Center

    Kepler, Karen B.

    This study investigated the ability of middle school teachers to use descriptive feedback from their students in changing their teaching behavior. One homeroom group of twenty-five students was observed in interaction with nine teachers of math, English, social studies, and science over a one-year period to elicit both quantifiable and qualitative…

  19. Adapting Tutorial Techniques to Perceptual Modalities of Deficient Readers.

    ERIC Educational Resources Information Center

    Worden, Thomas W.; Franklin, Mary R.

    1987-01-01

    This study investigated the effects on reading of matching perceptual strengths of second- and third-grade, below average readers. Experimental groups consisted of 24 predominantly visual and 24 predominantly kinesthetic learners. Gains were significant for experimentals over controls in word recognition and reading comprehension. (Author/BS)

  20. Adaptive jitter rejection technique applicable to airborne laser communication systems

    NASA Astrophysics Data System (ADS)

    Skormin, Victor A.; Tasullo, Mark A.; Busch, Timothy E.

    1994-08-01

    Satellite jitter adversely affects pointing, acquisition and tracking (PAT) functions of an intersatellite laser communication system. Reliable aircraft- based testing of PAT systems requires that the detrimental effects of aircraft jitter be controlled and a realistic satellite jitter environment be emulated. A novel jitter rejection technique, the self-tuning feedforward compensation scheme, is developed to minimize effects of aircraft vibration on the PAT terminal. The self-tuning results in the implicit characterization of the mechanical jitter propagation path thus facilitating the injection of prerecorded satellite jitter in the control circuitry of steering mirrors.

  1. Adaptive jitter rejection technique applicable to airborne laser communication systems

    NASA Astrophysics Data System (ADS)

    Skormin, Victor A.; Tascillo, Mark A.; Busch, Timothy E.

    1995-05-01

    Satellite jitter adversely affects the pointing, acquisition, and tracking (PAT) functions of an intersatellite laser communication system. Reliable aircraft-based testing of PAT systems requires that the detrimental effects of aircraft jitter be controlled and a realistic satellite jitter environment be emulated. A novel jitter rejection technique, the self-tuning feed-forward compensation scheme, is developed to minimize the effects of aircraft vibration on the PAT terminal. The self-tuning results in the implicit characterization of the mechanical jitter propagation path, thus facilitating the injection of prerecorded satellite jitter in the control circuitry of steering mirrors.

  2. Adaptation of Group A Streptococcus to Human Amniotic Fluid

    PubMed Central

    Sitkiewicz, Izabela; Green, Nicole M.; Guo, Nina; Bongiovanni, Ann M.; Witkin, Steven S.; Musser, James M.

    2010-01-01

    Background For more than 100 years, group A Streptococcus has been identified as a cause of severe and, in many cases, fatal infections of the female urogenital tract. Due to advances in hospital hygiene and the advent of antibiotics, this type of infection has been virtually eradicated. However, within the last three decades there has been an increase in severe intra- and post-partum infections attributed to GAS. Methodology We hypothesized that GAS alters its transcriptome to survive in human amniotic fluid (AF) and cause disease. To identify genes that were up or down regulated in response to growth in AF, GAS was grown in human AF or standard laboratory media (THY) and samples for expression microarray analysis were collected during mid-logarithmic, late-logarithmic, and stationary growth phases. Microarray analysis was performed using a custom Affymetrix chip and normalized hybridization values derived from three biological replicates were collected at each growth point. Ratios of AF/THY above a 2-fold change and P-value <0.05 were considered significant. Principal Findings The majority of changes in the GAS transcriptome involved down regulation of multiple adhesins and virulence factors and activation of the stress response. We observed significant changes in genes involved in the arginine deiminase pathway and in the nucleotide de novo synthesis pathway. Conclusions/Significance Our work provides new insight into how pathogenic bacteria respond to their environment to establish infection and cause disease. PMID:20352104

  3. Archerfish use their shooting technique to produce adaptive underwater jets.

    PubMed

    Dewenter, Jana; Gerullis, Peggy; Hecker, Alexander; Schuster, Stefan

    2017-03-15

    Archerfish are renowned for dislodging aerial prey using well-aimed shots of water. Recently it has been shown that these fish can shape their aerial jets by adjusting the dynamics of their mouth opening and closing. This allows the fish to adjust their jet to target distance so that they can forcefully hit prey over considerable distances. Here, we suggest that archerfish use the same technique to also actively control jets under water. Fired from close range, the underwater jets are powerful enough to lift up buried food particles, which the fish then can pick up. We trained fish so that we could monitor their mouth opening and closing maneuvers during underwater shooting and compare them with those employed in aerial shooting. Our analysis suggests that the fish use the same dynamic mechanism to produce aerial and underwater jets and that they employ the same basic technique to adjust their jets in both conditions. When food is buried in substrate that consists of large particles, the fish use a brief pulse, but they use a longer one when the substrate is more fine-grained. These findings extend the notion that archerfish can flexibly shape their jets to be appropriate in different contexts and suggest that archerfish shooting might have been shaped both by constraints in aerial and underwater shooting.

  4. Adaptive array technique for differential-phase reflectometry in QUEST

    SciTech Connect

    Idei, H. Hanada, K.; Zushi, H.; Nagata, K.; Mishra, K.; Itado, T.; Akimoto, R.; Yamamoto, M. K.

    2014-11-15

    A Phased Array Antenna (PAA) was considered as launching and receiving antennae in reflectometry to attain good directivity in its applied microwave range. A well-focused beam was obtained in a launching antenna application, and differential-phase evolution was properly measured by using a metal reflector plate in the proof-of-principle experiment at low power test facilities. Differential-phase evolution was also evaluated by using the PAA in the Q-shu University Experiment with Steady State Spherical Tokamak (QUEST). A beam-forming technique was applied in receiving phased-array antenna measurements. In the QUEST device that should be considered as a large oversized cavity, standing wave effect was significantly observed with perturbed phase evolution. A new approach using derivative of measured field on propagating wavenumber was proposed to eliminate the standing wave effect.

  5. Stochastic Leader Gravitational Search Algorithm for Enhanced Adaptive Beamforming Technique.

    PubMed

    Darzi, Soodabeh; Islam, Mohammad Tariqul; Tiong, Sieh Kiong; Kibria, Salehin; Singh, Mandeep

    2015-01-01

    In this paper, stochastic leader gravitational search algorithm (SL-GSA) based on randomized k is proposed. Standard GSA (SGSA) utilizes the best agents without any randomization, thus it is more prone to converge at suboptimal results. Initially, the new approach randomly choses k agents from the set of all agents to improve the global search ability. Gradually, the set of agents is reduced by eliminating the agents with the poorest performances to allow rapid convergence. The performance of the SL-GSA was analyzed for six well-known benchmark functions, and the results are compared with SGSA and some of its variants. Furthermore, the SL-GSA is applied to minimum variance distortionless response (MVDR) beamforming technique to ensure compatibility with real world optimization problems. The proposed algorithm demonstrates superior convergence rate and quality of solution for both real world problems and benchmark functions compared to original algorithm and other recent variants of SGSA.

  6. Stochastic Leader Gravitational Search Algorithm for Enhanced Adaptive Beamforming Technique

    PubMed Central

    Darzi, Soodabeh; Islam, Mohammad Tariqul; Tiong, Sieh Kiong; Kibria, Salehin; Singh, Mandeep

    2015-01-01

    In this paper, stochastic leader gravitational search algorithm (SL-GSA) based on randomized k is proposed. Standard GSA (SGSA) utilizes the best agents without any randomization, thus it is more prone to converge at suboptimal results. Initially, the new approach randomly choses k agents from the set of all agents to improve the global search ability. Gradually, the set of agents is reduced by eliminating the agents with the poorest performances to allow rapid convergence. The performance of the SL-GSA was analyzed for six well-known benchmark functions, and the results are compared with SGSA and some of its variants. Furthermore, the SL-GSA is applied to minimum variance distortionless response (MVDR) beamforming technique to ensure compatibility with real world optimization problems. The proposed algorithm demonstrates superior convergence rate and quality of solution for both real world problems and benchmark functions compared to original algorithm and other recent variants of SGSA. PMID:26552032

  7. My Solar System: A Developmentally Adapted Eco-Mapping Technique for Children

    ERIC Educational Resources Information Center

    Curry, Jennifer R.; Fazio-Griffith, Laura J.; Rohr, Shannon N.

    2008-01-01

    Counseling children requires specific skills and techniques, such as play therapy and expressive arts, to address developmental manifestations and to facilitate the understanding of presenting problems. This article outlines an adapted eco-mapping activity that can be used as a creative counseling technique with children in order to promote…

  8. Application of Physiological Self-Regulation and Adaptive Task Allocation Techniques for Controlling Operator Hazardous States of Awareness

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Pope, Alan T.; Freeman, Frederick G.

    2001-01-01

    Prinzel, Hadley, Freeman, and Mikulka found that adaptive task allocation significantly enhanced performance only when used at the endpoints of the task workload continuum (i.e., very low or high workload), but that the technique degraded performance if invoked during other levels of task demand. These researchers suggested that other techniques should be used in conjunction with adaptive automation to help minimize the onset of hazardous states of awareness (HSA) and keep the operator 'in-the-loop.' The paper reports on such a technique that uses psychophysiological self-regulation to modulate the level of task engagement. Eighteen participants were assigned to three groups (self-regulation, false feedback, and control) and performed a compensatory tracking task that was cycled between three levels of task difficulty on the basis of the electroencephalogram (EEG) record. Those participants who had received self-regulation training performed significantly better and reported lower NASA-TLX scores than participants in the false feedback and control groups. Furthermore, the false feedback and control groups had significantly more task allocations resulting in return-to-manual performance decrements and higher EEG difference scores. Theoretical and practical implications of these results for adaptive automation are discussed.

  9. Recruiting hard-to-reach United States population sub-groups via adaptations of snowball sampling strategy

    PubMed Central

    Sadler, Georgia Robins; Lee, Hau-Chen; Seung-Hwan Lim, Rod; Fullerton, Judith

    2011-01-01

    Nurse researchers and educators often engage in outreach to narrowly defined populations. This article offers examples of how variations on the snowball sampling recruitment strategy can be applied in the creation of culturally appropriate, community-based information dissemination efforts related to recruitment to health education programs and research studies. Examples from the primary author’s program of research are provided to demonstrate how adaptations of snowball sampling can be effectively used in the recruitment of members of traditionally underserved or vulnerable populations. The adaptation of snowball sampling techniques, as described in this article, helped the authors to gain access to each of the more vulnerable population groups of interest. The use of culturally sensitive recruitment strategies is both appropriate and effective in enlisting the involvement of members of vulnerable populations. Adaptations of snowball sampling strategies should be considered when recruiting participants for education programs or subjects for research studies when recruitment of a population based sample is not essential. PMID:20727089

  10. An adaptive laser beam shaping technique based on a genetic algorithm

    NASA Astrophysics Data System (ADS)

    Yang, Ping; Liu, Yuan; Yang, Wei; Ao, Minwu; Hu, Shijie; Xu, Bing; Jiang, Wenhan

    2007-09-01

    A new adaptive beam intensity shaping technique based on the combination of a 19-element piezo-electricity deformable mirror (DM) and a global genetic algorithm is presented. This technique can adaptively adjust the voltages of the 19 actuators on the DM to reduce the difference between the target beam shape and the actual beam shape. Numerical simulations and experimental results show that within the stroke range of the DM, this technique can be well used to create the given beam intensity profiles on the focal plane.

  11. Adaptive thresholding technique for retinal vessel segmentation based on GLCM-energy information.

    PubMed

    Mapayi, Temitope; Viriri, Serestina; Tapamo, Jules-Raymond

    2015-01-01

    Although retinal vessel segmentation has been extensively researched, a robust and time efficient segmentation method is highly needed. This paper presents a local adaptive thresholding technique based on gray level cooccurrence matrix- (GLCM-) energy information for retinal vessel segmentation. Different thresholds were computed using GLCM-energy information. An experimental evaluation on DRIVE database using the grayscale intensity and Green Channel of the retinal image demonstrates the high performance of the proposed local adaptive thresholding technique. The maximum average accuracy rates of 0.9511 and 0.9510 with maximum average sensitivity rates of 0.7650 and 0.7641 were achieved on DRIVE and STARE databases, respectively. When compared to the widely previously used techniques on the databases, the proposed adaptive thresholding technique is time efficient with a higher average sensitivity and average accuracy rates in the same range of very good specificity.

  12. Group Oral Exams: Exploring Assessment Techniques for New Instructional Paradigms.

    ERIC Educational Resources Information Center

    Mandeville, Thomas F.; Menchaca, Velma

    1994-01-01

    Describes how a group oral final exam was designed and administered in a block of two teacher education courses taught within the social constructivist perspective. Advocates such group oral exam practices as consistent with valid assessment guidelines. Discusses limitations. (HB)

  13. Group Therapy Techniques for Sexually Abused Preteen Girls.

    ERIC Educational Resources Information Center

    Berman, Pearl

    1990-01-01

    Describes an open-ended, structured, highly intensive therapy group for sexually abused preteen girls that was the primary mode of treatment for 11 girls from low-income, rural White families with numerous problems. Unique features of the group included simultaneous group and individualized goals. (Author/BB)

  14. Group Therapy Techniques for Sexually Abused Preteen Girls.

    ERIC Educational Resources Information Center

    Berman, Pearl

    1990-01-01

    Describes an open-ended, structured, highly intensive therapy group for sexually abused preteen girls that was the primary mode of treatment for 11 girls from low-income, rural White families with numerous problems. Unique features of the group included simultaneous group and individualized goals. (Author/BB)

  15. Adaptations of advanced safety and reliability techniques to petroleum and other industries

    NASA Technical Reports Server (NTRS)

    Purser, P. E.

    1974-01-01

    The underlying philosophy of the general approach to failure reduction and control is presented. Safety and reliability management techniques developed in the industries which have participated in the U.S. space and defense programs are described along with adaptations to nonaerospace activities. The examples given illustrate the scope of applicability of these techniques. It is indicated that any activity treated as a 'system' is a potential user of aerospace safety and reliability management techniques.

  16. Adaptability of laser diffraction measurement technique in soil physics methodology

    NASA Astrophysics Data System (ADS)

    Barna, Gyöngyi; Szabó, József; Rajkai, Kálmán; Bakacsi, Zsófia; Koós, Sándor; László, Péter; Hauk, Gabriella; Makó, András

    2016-04-01

    There are intentions all around the world to harmonize soils' particle size distribution (PSD) data by the laser diffractometer measurements (LDM) to that of the sedimentation techniques (pipette or hydrometer methods). Unfortunately, up to the applied methodology (e. g. type of pre-treatments, kind of dispersant etc.), PSDs of the sedimentation methods (due to different standards) are dissimilar and could be hardly harmonized with each other, as well. A need was arisen therefore to build up a database, containing PSD values measured by the pipette method according to the Hungarian standard (MSZ-08. 0205: 1978) and the LDM according to a widespread and widely used procedure. In our current publication the first results of statistical analysis of the new and growing PSD database are presented: 204 soil samples measured with pipette method and LDM (Malvern Mastersizer 2000, HydroG dispersion unit) were compared. Applying usual size limits at the LDM, clay fraction was highly under- and silt fraction was overestimated compared to the pipette method. Subsequently soil texture classes determined from the LDM measurements significantly differ from results of the pipette method. According to previous surveys and relating to each other the two dataset to optimizing, the clay/silt boundary at LDM was changed. Comparing the results of PSDs by pipette method to that of the LDM, in case of clay and silt fractions the modified size limits gave higher similarities. Extension of upper size limit of clay fraction from 0.002 to 0.0066 mm, and so change the lower size limit of silt fractions causes more easy comparability of pipette method and LDM. Higher correlations were found between clay content and water vapor adsorption, specific surface area in case of modified limit, as well. Texture classes were also found less dissimilar. The difference between the results of the two kind of PSD measurement methods could be further reduced knowing other routinely analyzed soil parameters

  17. Group therapy techniques for sexually abused preteen girls.

    PubMed

    Berman, P

    1990-01-01

    This article describes an open-ended, structured, highly intensive therapy group for sexually abused preteen girls that was the primary mode of treatment for 11 girls from multiproblem, low-income, rural, white families. The active support of Child Protective Service workers was important in maintaining the girls in treatment in the face of strong parental opposition. Unique features of the group included simultaneous group goals and individualized goals. A case description illustrates the makeup and functioning of the program.

  18. Application of Avco data analysis and prediction techniques (ADAPT) to prediction of sunspot activity

    NASA Technical Reports Server (NTRS)

    Hunter, H. E.; Amato, R. A.

    1972-01-01

    The results are presented of the application of Avco Data Analysis and Prediction Techniques (ADAPT) to derivation of new algorithms for the prediction of future sunspot activity. The ADAPT derived algorithms show a factor of 2 to 3 reduction in the expected 2-sigma errors in the estimates of the 81-day running average of the Zurich sunspot numbers. The report presents: (1) the best estimates for sunspot cycles 20 and 21, (2) a comparison of the ADAPT performance with conventional techniques, and (3) specific approaches to further reduction in the errors of estimated sunspot activity and to recovery of earlier sunspot historical data. The ADAPT programs are used both to derive regression algorithm for prediction of the entire 11-year sunspot cycle from the preceding two cycles and to derive extrapolation algorithms for extrapolating a given sunspot cycle based on any available portion of the cycle.

  19. Real-time nondestructive testing of composite aeronautical structures with a self-adaptive ultrasonic technique

    NASA Astrophysics Data System (ADS)

    Robert, S.; Casula, O.; Roy, O.; Neau, G.

    2013-07-01

    In the aeronautical industry, composite structures under testing often have complex and variable geometries. In such cases, an optimal use of ultrasonic transducer arrays requires specific algorithms in electronic systems in order to achieve rapid and reliable inspections. To fulfil such requirements, a new real-time and adaptive technique is presented. The surface adaptive ultrasound (SAUL) technique is based on an iterative algorithm that does not require a prior knowledge of the geometrical properties of the inspected domain. All different parts of a given component can be controlled using the same transducer array, such as a conventional linear array with a flat shape. In this paper, the adaptive processing is demonstrated through acquisitions performed with different typical aircraft composite structures. In addition, we present a new surface reconstruction algorithm. This fast algorithm is efficient and can be coupled with the real-time adaptive processing to reconstruct SAUL images and, then, to improve the characterization of flaws in composite materials.

  20. Domain adaptation problems: a DASVM classification technique and a circular validation strategy.

    PubMed

    Bruzzone, Lorenzo; Marconcini, Mattia

    2010-05-01

    This paper addresses pattern classification in the framework of domain adaptation by considering methods that solve problems in which training data are assumed to be available only for a source domain different (even if related) from the target domain of (unlabeled) test data. Two main novel contributions are proposed: 1) a domain adaptation support vector machine (DASVM) technique which extends the formulation of support vector machines (SVMs) to the domain adaptation framework and 2) a circular indirect accuracy assessment strategy for validating the learning of domain adaptation classifiers when no true labels for the target--domain instances are available. Experimental results, obtained on a series of two-dimensional toy problems and on two real data sets related to brain computer interface and remote sensing applications, confirmed the effectiveness and the reliability of both the DASVM technique and the proposed circular validation strategy.

  1. A conforming to interface structured adaptive mesh refinement technique for modeling fracture problems

    NASA Astrophysics Data System (ADS)

    Soghrati, Soheil; Xiao, Fei; Nagarajan, Anand

    2016-12-01

    A Conforming to Interface Structured Adaptive Mesh Refinement (CISAMR) technique is introduced for the automated transformation of a structured grid into a conforming mesh with appropriate element aspect ratios. The CISAMR algorithm is composed of three main phases: (i) Structured Adaptive Mesh Refinement (SAMR) of the background grid; (ii) r-adaptivity of the nodes of elements cut by the crack; (iii) sub-triangulation of the elements deformed during the r-adaptivity process and those with hanging nodes generated during the SAMR process. The required considerations for the treatment of crack tips and branching cracks are also discussed in this manuscript. Regardless of the complexity of the problem geometry and without using iterative smoothing or optimization techniques, CISAMR ensures that aspect ratios of conforming elements are lower than three. Multiple numerical examples are presented to demonstrate the application of CISAMR for modeling linear elastic fracture problems with intricate morphologies.

  2. A conforming to interface structured adaptive mesh refinement technique for modeling fracture problems

    NASA Astrophysics Data System (ADS)

    Soghrati, Soheil; Xiao, Fei; Nagarajan, Anand

    2017-04-01

    A Conforming to Interface Structured Adaptive Mesh Refinement (CISAMR) technique is introduced for the automated transformation of a structured grid into a conforming mesh with appropriate element aspect ratios. The CISAMR algorithm is composed of three main phases: (i) Structured Adaptive Mesh Refinement (SAMR) of the background grid; (ii) r-adaptivity of the nodes of elements cut by the crack; (iii) sub-triangulation of the elements deformed during the r-adaptivity process and those with hanging nodes generated during the SAMR process. The required considerations for the treatment of crack tips and branching cracks are also discussed in this manuscript. Regardless of the complexity of the problem geometry and without using iterative smoothing or optimization techniques, CISAMR ensures that aspect ratios of conforming elements are lower than three. Multiple numerical examples are presented to demonstrate the application of CISAMR for modeling linear elastic fracture problems with intricate morphologies.

  3. Focus Groups: An Important Research Technique for Internal Evaluation Units.

    ERIC Educational Resources Information Center

    Duffy, Barbara Poitras

    1993-01-01

    The use of focus groups by the Federal Bureau of Investigation as a tool of internal evaluation is described. Focus groups are used in an environment where credibility is key to achieving meaningful cooperation. Issues for consideration by other evaluators interested in the approach are summarized. (SLD)

  4. 75 FR 20381 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation... technical work group (TWG), a monitoring and research center, and independent review panels. The AMWG makes.... (PDT) to ensure that the connections work properly. The one hour test Web site is: https://usgs.webex...

  5. Adapting and Evaluating a Tree of Life Group for Women with Learning Disabilities

    ERIC Educational Resources Information Center

    Randle-Phillips, Cathy; Farquhar, Sarah; Thomas, Sally

    2016-01-01

    Background: This study describes how a specific narrative therapy approach called 'the tree of life' was adapted to run a group for women with learning disabilities. The group consisted of four participants and ran for five consecutive weeks. Materials and Methods: Participants each constructed a tree to represent their lives and presented their…

  6. Adaptation and Flexibility When Conducting and Planning Peer Study Group Review Sessions

    ERIC Educational Resources Information Center

    Arendale, David R.; Hanes, Amanda R.

    2016-01-01

    Based on an evaluation of the professional literature of postsecondary learning assistance, little is known about decisions made by student leaders during their peer study group review sessions. Our research question for this study is "How did study group leaders adapt their role to better meet the needs of the students who participated in…

  7. Adaptation and Flexibility When Conducting and Planning Peer Study Group Review Sessions

    ERIC Educational Resources Information Center

    Arendale, David R.; Hanes, Amanda R.

    2016-01-01

    Based on an evaluation of the professional literature of postsecondary learning assistance, little is known about decisions made by student leaders during their peer study group review sessions. Our research question for this study is "How did study group leaders adapt their role to better meet the needs of the students who participated in…

  8. Adapting and Evaluating a Tree of Life Group for Women with Learning Disabilities

    ERIC Educational Resources Information Center

    Randle-Phillips, Cathy; Farquhar, Sarah; Thomas, Sally

    2016-01-01

    Background: This study describes how a specific narrative therapy approach called 'the tree of life' was adapted to run a group for women with learning disabilities. The group consisted of four participants and ran for five consecutive weeks. Materials and Methods: Participants each constructed a tree to represent their lives and presented their…

  9. 73 FR 500 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2008-01-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation... technical work group (TWG), a monitoring and research center, and independent review panels. The AMWG...

  10. Development and Verification of Unstructured Adaptive Mesh Technique with Edge Compatibility

    NASA Astrophysics Data System (ADS)

    Ito, Kei; Kunugi, Tomoaki; Ohshima, Hiroyuki

    In the design study of the large-sized sodium-cooled fast reactor (JSFR), one key issue is suppression of gas entrainment (GE) phenomena at a gas-liquid interface. Therefore, the authors have been developed a high-precision CFD algorithm to evaluate the GE phenomena accurately. The CFD algorithm has been developed on unstructured meshes to establish an accurate modeling of JSFR system. For two-phase interfacial flow simulations, a high-precision volume-of-fluid algorithm is employed. It was confirmed that the developed CFD algorithm could reproduce the GE phenomena in a simple GE experiment. Recently, the authors have been developed an important technique for the simulation of the GE phenomena in JSFR. That is an unstructured adaptive mesh technique which can apply fine cells dynamically to the region where the GE occurs in JSFR. In this paper, as a part of the development, a two-dimensional unstructured adaptive mesh technique is discussed. In the two-dimensional adaptive mesh technique, each cell is refined isotropically to reduce distortions of the mesh. In addition, connection cells are formed to eliminate the edge incompatibility between refined and non-refined cells. The two-dimensional unstructured adaptive mesh technique is verified by solving well-known lid-driven cavity flow problem. As a result, the two-dimensional unstructured adaptive mesh technique succeeds in providing a high-precision solution, even though poor-quality distorted initial mesh is employed. In addition, the simulation error on the two-dimensional unstructured adaptive mesh is much less than the error on the structured mesh with a larger number of cells.

  11. Marginal adaptation of mineral trioxide aggregate (MTA) to root dentin surface with orthograde/retrograde application techniques: A microcomputed tomographic analysis

    PubMed Central

    Al Fouzan, Khalid; Awadh, Mohammed; Badwelan, Moahmmed; Gamal, Abeer; Geevarghese, Amrita; Babhair, Samar; Al-Rejaie, Mansour; Al Hezaimi, Khalid; Rotstein, Ilan

    2015-01-01

    Background: Achieving a good apical seal for root canals is known to be associated with good mineral trioxide aggregate (MTA) adaptation to dentin. Aims: This study aims to compare the marginal adaptation of MTA with root dentin between orthograde and retrograde application techniques using microcomputed tomography (micro-CT) analysis. Settings and Design: Fifty-two single-rooted human teeth were divided into four equal groups: (Group 1) Retrograde MTA (RMTA), (Group 2) Orthograde MTA (OMTA), (Group 3) Etched RMTA (ERMTA), and (Group 4) Etched OMTA (EOMTA). Materials and Methods: For Group 1, 3-mm retrograde cavities were prepared and filled with MTA. For Group 2, the apical 6 mm of the canals were filled with MTA and sealed with sealer cement and warm gutta-percha. In Groups 3 and 4, canals were treated the same as Groups 1 and 2, respectively, except that before placing the MTA, canals were irrigated with 17% ethylenediaminetetraacetic acid (EDTA). After 48 hours, all the teeth were analyzed using a micro-CT scanner. Statistical Analysis: Mean dentin-MTA contact and the mean length and width of each gap was analysed using one-way analysis of variance (ANOVA). Statistical significance was set at an α level of 5%. Results: No significant difference in gap volumes was observed in the dentin-MTA adaptation in both orthograde and retrograde application techniques. However, significant difference in the gap volumes was observed between RMTA and ERMTA (P = 0.045). Etching significantly improved the MTA-Dentin adaptation (P < 0.05). The type of application technique did not significantly improve the dentin-MTA adaptation, instead with the use of 17% EDTA, a significant improvement could be achieved. Conclusion: Within the limitations of the present study, it concludes that MTA adaptation to dentin tooth structure is not significantly different between an orthograde and retrograde approach. However, the use of EDTA significantly improved the MTA-Dentin adaptation. PMID

  12. A simple and flexible graphical approach for adaptive group-sequential clinical trials.

    PubMed

    Sugitani, Toshifumi; Bretz, Frank; Maurer, Willi

    2016-01-01

    In this article, we introduce a graphical approach to testing multiple hypotheses in group-sequential clinical trials allowing for midterm design modifications. It is intended for structured study objectives in adaptive clinical trials and extends the graphical group-sequential designs from Maurer and Bretz (Statistics in Biopharmaceutical Research 2013; 5: 311-320) to adaptive trial designs. The resulting test strategies can be visualized graphically and performed iteratively. We illustrate the methodology with two examples from our clinical trial practice. First, we consider a three-armed gold-standard trial with the option to reallocate patients to either the test drug or the active control group, while stopping the recruitment of patients to placebo, after having demonstrated superiority of the test drug over placebo at an interim analysis. Second, we consider a confirmatory two-stage adaptive design with treatment selection at interim.

  13. Grouping Students for Effective Learning in the ABE Classroom. TECHNIQUES.

    ERIC Educational Resources Information Center

    Davis, Richard S.; Davis, Ginger L.

    1987-01-01

    For many learners in adult basic education (ABE) or General Educational Development (GED) classrooms, the difference between staying with the program and leaving prematurely is often related to the degree of the student's involvement with other members of the class. Grouping students to work together has both support- and learning-related…

  14. An adaptive technique for estimating the atmospheric density profile during the AE mission

    NASA Technical Reports Server (NTRS)

    Argentiero, P.

    1973-01-01

    A technique is presented for processing accelerometer data obtained during the AE missions in order to estimate the atmospheric density profile. A minimum variance, adaptive filter is utilized. The trajectory of the probe and probe parameters are in a consider mode where their estimates are unimproved but their associated uncertainties are permitted an impact on filter behavior. Simulations indicate that the technique is effective in estimating a density profile to within a few percentage points.

  15. Particle Swarm Social Model for Group Social Learning in Adaptive Environment

    SciTech Connect

    Cui, Xiaohui; Potok, Thomas E; Treadwell, Jim N; Patton, Robert M; Pullum, Laura L

    2008-01-01

    This report presents a study of integrating particle swarm algorithm, social knowledge adaptation and multi-agent approaches for modeling the social learning of self-organized groups and their collective searching behavior in an adaptive environment. The objective of this research is to apply the particle swarm metaphor as a model of social learning for a dynamic environment. The research provides a platform for understanding and insights into knowledge discovery and strategic search in human self-organized social groups, such as insurgents or online communities.

  16. SWAT system performance predictions. Project report. [SWAT (Short-Wavelength Adaptive Techniques)

    SciTech Connect

    Parenti, R.R.; Sasiela, R.J.

    1993-03-10

    In the next phase of Lincoln Laboratory's SWAT (Short-Wavelength Adaptive Techniques) program, the performance of a 241-actuator adaptive-optics system will be measured using a variety of synthetic-beacon geometries. As an aid in this experimental investigation, a detailed set of theoretical predictions has also been assembled. The computational tools that have been applied in this study include a numerical approach in which Monte-Carlo ray-trace simulations of accumulated phase error are developed, and an analytical analysis of the expected system behavior. This report describes the basis of these two computational techniques and compares their estimates of overall system performance. Although their regions of applicability tend to be complementary rather than redundant, good agreement is usually obtained when both sets of results can be derived for the same engagement scenario.... Adaptive optics, Phase conjugation, Atmospheric turbulence Synthetic beacon, Laser guide star.

  17. Application of adaptive antenna techniques to future commercial satellite communications. Executive summary

    NASA Technical Reports Server (NTRS)

    Ersoy, L.; Lee, E. A.; Matthews, E. W.

    1987-01-01

    The purpose of this contract was to identify the application of adaptive antenna technique in future operational commercial satellite communication systems and to quantify potential benefits. The contract consisted of two major subtasks. Task 1, Assessment of Future Commercial Satellite System Requirements, was generally referred to as the Adaptive section. Task 2 dealt with Pointing Error Compensation Study for a Multiple Scanning/Fixed Spot Beam Reflector Antenna System and was referred to as the reconfigurable system. Each of these tasks was further subdivided into smaller subtasks. It should also be noted that the reconfigurable system is usually defined as an open-loop system while the adaptive system is a closed-loop system. The differences between the open- and closed-loop systems were defined. Both the adaptive and reconfigurable systems were explained and the potential applications of such systems were presented in the context of commercial communication satellite systems.

  18. Impulse radar imaging for dispersive concrete using inverse adaptive filtering techniques

    SciTech Connect

    Arellano, J.; Hernandez, J.M.; Brase, J.

    1993-05-01

    This publication addresses applications of a delayed inverse model adaptive filter for modeled data obtained from short-pulse radar reflectometry. To determine the integrity of concrete, a digital adaptive filter was used, which allows compensation of dispersion and clutter generated by the concrete. A standard set of weights produced by an adaptive filter are used on modeled data to obtain the inverse-impulse response of the concrete. The data for this report include: Multiple target, nondispersive data; single-target, variable-size dispersive data; single-target, variable-depth dispersive data; and single-target, variable transmitted-pulse-width dispersive data. Results of this simulation indicate that data generated by the weights of the adaptive filter, coupled with a two-dimensional, synthetic-aperture focusing technique, successfully generate two-dimensional images of targets within the concrete from modeled data.

  19. Voice Therapy Techniques Adapted to Treatment of Habit Cough: A Pilot Study.

    ERIC Educational Resources Information Center

    Blager, Florence B.; And Others

    1988-01-01

    Individuals with long-standing habit cough having no organic basis can be successfully treated with a combination of psychotherapy and speech therapy. Techniques for speech therapy are adapted from those used with hyperfunctional voice disorders to fit this debilitating laryngeal disorder. (Author)

  20. Adaptive Denoising Technique for Robust Analysis of Functional Magnetic Resonance Imaging Data

    DTIC Science & Technology

    2007-11-02

    or receive while t fMRI o versatil of epoc method ER-fM to the studies comes intra-su functioADAPTIVE DENOISING TECHNIQUE FOR ROBUST ANALYSIS OF...supported in part by the Center for Advanced Software and Biomedical Engineering Consultations (CASBEC), Cairo University, and IBE Technologies , Egypt

  1. An Approach for Automatic Generation of Adaptive Hypermedia in Education with Multilingual Knowledge Discovery Techniques

    ERIC Educational Resources Information Center

    Alfonseca, Enrique; Rodriguez, Pilar; Perez, Diana

    2007-01-01

    This work describes a framework that combines techniques from Adaptive Hypermedia and Natural Language processing in order to create, in a fully automated way, on-line information systems from linear texts in electronic format, such as textbooks. The process is divided into two steps: an "off-line" processing step, which analyses the source text,…

  2. An Approach for Automatic Generation of Adaptive Hypermedia in Education with Multilingual Knowledge Discovery Techniques

    ERIC Educational Resources Information Center

    Alfonseca, Enrique; Rodriguez, Pilar; Perez, Diana

    2007-01-01

    This work describes a framework that combines techniques from Adaptive Hypermedia and Natural Language processing in order to create, in a fully automated way, on-line information systems from linear texts in electronic format, such as textbooks. The process is divided into two steps: an "off-line" processing step, which analyses the source text,…

  3. Marginal and internal adaptation of ceramic crown restorations fabricated with CAD/CAM technology and the heat-press technique.

    PubMed

    Mously, Hisham A; Finkelman, Matthew; Zandparsa, Roya; Hirayama, Hiroshi

    2014-08-01

    The accuracy of chairside computer-aided design and computer-aided manufacturing (CAD/CAM) restorations is questionable, and the effect of the die spacer settings is not well stated in the literature. The purpose of the study was to evaluate the marginal and internal adaptation of E4D crowns fabricated with different spacer thicknesses and to compare these crowns with those fabricated with the heat-press technique. The E4D system was used to fabricate 30 crowns for the first 3 groups, with different spacer thickness settings: 30 μm, 60 μm, and 100 μm. In the fourth group, 10 lithium disilicate crowns were fabricated with the heat-press technique. The occlusal gap, axial gap, vertical marginal gap, and absolute marginal discrepancy were evaluated by x-ray microtomography. Statistical significance was assessed with the Kruskal-Wallis test (α=.05). For post hoc analyses, the Mann-Whitney U test was used alongside the Bonferroni correction for multiple comparisons (α=.008). Within the CAD/CAM groups, the 30-μm spacer thickness resulted in the lowest median axial gap (90.04 μm), whereas the 60-μm spacer thickness resulted in the lowest median occlusal gap (152.39 μm). The median marginal gap values of the CAD/CAM-60 group (49.35 μm) and CAD/CAM-100 group (46.65 μm) were lower than those of the CAD/CAM-30 group (55.18 μm). No significant differences among the CAD/CAM groups were observed for absolute marginal discrepancy. The heat-press group had significantly different values than those of the CAD/CAM groups. The spacer thickness and fabrication technique affected the adaptation of ceramic crowns. The heat-press group yielded the best marginal and internal crown adaptation results. The 30- or 60-μm spacer settings are recommended for the E4D CAD/CAM system. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  4. Adaptive phase matching probe-injection technique for enhancement of Brillouin scattering signal

    NASA Astrophysics Data System (ADS)

    Li, Hongwei; Shi, Guangyao; Lv, Yuelan; Zhang, Hongying; Gao, Wei

    2017-08-01

    We report on a simple and efficient method for enhancing Brillouin scattering signal, i.e., adaptive phase matching (APM) probe-injection technique. In this technique, a low-polarization broad-spectrum probe wave is injected opposite to the pump, which can enhance any stokes signal in its APM range instantly by selective stimulated Brillouin amplification. With advantages of simple scheme, real-time multi-signal enhancement and sweep-free measurement, this technique has a great potential for improving the signal-to-noise ratio of Brillouin gain spectrum in the Brillouin scattering application systems.

  5. Auto-adaptive robot-aided therapy using machine learning techniques.

    PubMed

    Badesa, Francisco J; Morales, Ricardo; Garcia-Aracil, Nicolas; Sabater, J M; Casals, Alicia; Zollo, Loredana

    2014-09-01

    This paper presents an application of a classification method to adaptively and dynamically modify the therapy and real-time displays of a virtual reality system in accordance with the specific state of each patient using his/her physiological reactions. First, a theoretical background about several machine learning techniques for classification is presented. Then, nine machine learning techniques are compared in order to select the best candidate in terms of accuracy. Finally, first experimental results are presented to show that the therapy can be modulated in function of the patient state using machine learning classification techniques. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. Optimal Pid Tuning for Power System Stabilizers Using Adaptive Particle Swarm Optimization Technique

    NASA Astrophysics Data System (ADS)

    Oonsivilai, Anant; Marungsri, Boonruang

    2008-10-01

    An application of the intelligent search technique to find optimal parameters of power system stabilizer (PSS) considering proportional-integral-derivative controller (PID) for a single-machine infinite-bus system is presented. Also, an efficient intelligent search technique, adaptive particle swarm optimization (APSO), is engaged to express usefulness of the intelligent search techniques in tuning of the PID—PSS parameters. Improve damping frequency of system is optimized by minimizing an objective function with adaptive particle swarm optimization. At the same operating point, the PID—PSS parameters are also tuned by the Ziegler-Nichols method. The performance of proposed controller compared to the conventional Ziegler-Nichols PID tuning controller. The results reveal superior effectiveness of the proposed APSO based PID controller.

  7. 78 FR 35312 - Trinity Adaptive Management Working Group; Public Meeting, Teleconference and Web-Based Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ... Web-Based Meeting AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice. SUMMARY: We, the U.S. Fish and Wildlife Service, announce a public meeting, teleconference and web-based meeting of the Trinity Adaptive Management Working Group (TAMWG). DATES: Public meeting, Teleconference, and web-based...

  8. 78 FR 49281 - Trinity Adaptive Management Working Group; Public Meeting, Teleconference and Web-Based Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... Web-Based Meeting AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice. SUMMARY: We, the U.S. Fish and Wildlife Service, announce a public meeting, teleconference, and web-based meeting of the Trinity Adaptive Management Working Group (TAMWG). DATES: Public meeting, Teleconference, and web-based...

  9. 78 FR 17226 - Trinity Adaptive Management Working Group; Public Meeting, Teleconference and Web-Based Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ... Web-Based Meeting AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice. SUMMARY: We, the U.S. Fish and Wildlife Service, announce a public meeting, teleconference and web-based meeting of the Trinity Adaptive Management Working Group (TAMWG). DATES: Public meeting, Teleconference, and web-based...

  10. Group-Work in the Design of Complex Adaptive Learning Strategies

    ERIC Educational Resources Information Center

    Mavroudi, Anna; Hadzilacos, Thanasis

    2013-01-01

    This paper presents a case study where twelve graduate students undertook the demanding role of the adaptive e-course developer and worked collaboratively on an authentic and complex design task in the context of open and distance tertiary education. The students had to work in groups in order to conceptualise and design a learning scenario for…

  11. 76 FR 584 - Glen Canyon Dam Adaptive Management Program Work Group (AMWG)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ... assessments, (3) Colorado River Basin hydrology, (4) and the Long-Term Experimental and Management Plan. In... provided to Glen Knowles, Bureau of Reclamation, Upper Colorado Regional Office, 125 South State Street.... Glen Knowles, Chief, Adaptive Management Work Group, Environmental Resources Division, Upper...

  12. Seismic Hazard Analysis Using the Adaptive Kernel Density Estimation Technique for Chennai City

    NASA Astrophysics Data System (ADS)

    Ramanna, C. K.; Dodagoudar, G. R.

    2012-01-01

    Conventional method of probabilistic seismic hazard analysis (PSHA) using the Cornell-McGuire approach requires identification of homogeneous source zones as the first step. This criterion brings along many issues and, hence, several alternative methods to hazard estimation have come up in the last few years. Methods such as zoneless or zone-free methods, modelling of earth's crust using numerical methods with finite element analysis, have been proposed. Delineating a homogeneous source zone in regions of distributed seismicity and/or diffused seismicity is rather a difficult task. In this study, the zone-free method using the adaptive kernel technique to hazard estimation is explored for regions having distributed and diffused seismicity. Chennai city is in such a region with low to moderate seismicity so it has been used as a case study. The adaptive kernel technique is statistically superior to the fixed kernel technique primarily because the bandwidth of the kernel is varied spatially depending on the clustering or sparseness of the epicentres. Although the fixed kernel technique has proven to work well in general density estimation cases, it fails to perform in the case of multimodal and long tail distributions. In such situations, the adaptive kernel technique serves the purpose and is more relevant in earthquake engineering as the activity rate probability density surface is multimodal in nature. The peak ground acceleration (PGA) obtained from all the three approaches (i.e., the Cornell-McGuire approach, fixed kernel and adaptive kernel techniques) for 10% probability of exceedance in 50 years is around 0.087 g. The uniform hazard spectra (UHS) are also provided for different structural periods.

  13. Comparison of denture base adaptation between CAD-CAM and conventional fabrication techniques.

    PubMed

    Goodacre, Brian J; Goodacre, Charles J; Baba, Nadim Z; Kattadiyil, Mathew T

    2016-08-01

    Currently no data comparing the denture base adaptation of CAD-CAM and conventional denture processing techniques have been reported. The purpose of this in vitro study was to compare the denture base adaptation of pack and press, pour, injection, and CAD-CAM techniques for fabricating dentures to determine which process produces the most accurate and reproducible adaptation. A definitive cast was duplicated to create 40 gypsum casts that were laser scanned before any fabrication procedures were initiated. A master denture was made using the CAD-CAM process and was then used to create a putty mold for the fabrication of 30 standardized wax festooned dentures, 10 for each of the conventional processing techniques (pack and press, pour, injection). Scan files from 10 casts were sent to Global Dental Science, LLC for fabrication of the CAD-CAM test specimens. After specimens for each of the 4 techniques had been fabricated, they were hydrated for 24 hours and the intaglio surface laser scanned. The scan file of each denture was superimposed on the scan file of the corresponding preprocessing cast using surface matching software. Measurements were made at 60 locations, providing evaluation of fit discrepancies at the following areas: apex of the denture border, 6 mm from the denture border, crest of the ridge, palate, and posterior palatal seal. The use of median and interquartile range was used to assess accuracy and reproducibility. The Levine and Kruskal-Wallis analysis of variance was used to evaluate differences between processing techniques at the 5 specified locations (α=.05). The ranking of results based on median and interquartile range determined that the accuracy and reproducibility of the CAD-CAM technique was more consistently localized around zero at 3 of the 5 locations. Therefore, the CAD-CAM technique showed the best combination of accuracy and reproducibility among the tested fabrication techniques. The pack and press technique was more accurate at

  14. Adaptive subdomain modeling: A multi-analysis technique for ocean circulation models

    NASA Astrophysics Data System (ADS)

    Altuntas, Alper; Baugh, John

    2017-07-01

    Many coastal and ocean processes of interest operate over large temporal and geographical scales and require a substantial amount of computational resources, particularly when engineering design and failure scenarios are also considered. This study presents an adaptive multi-analysis technique that improves the efficiency of these computations when multiple alternatives are being simulated. The technique, called adaptive subdomain modeling, concurrently analyzes any number of child domains, with each instance corresponding to a unique design or failure scenario, in addition to a full-scale parent domain providing the boundary conditions for its children. To contain the altered hydrodynamics originating from the modifications, the spatial extent of each child domain is adaptively adjusted during runtime depending on the response of the model. The technique is incorporated in ADCIRC++, a re-implementation of the popular ADCIRC ocean circulation model with an updated software architecture designed to facilitate this adaptive behavior and to utilize concurrent executions of multiple domains. The results of our case studies confirm that the method substantially reduces computational effort while maintaining accuracy.

  15. Multi-Level Adaptive Techniques (MLAT) for singular-perturbation problems

    NASA Technical Reports Server (NTRS)

    Brandt, A.

    1978-01-01

    The multilevel (multigrid) adaptive technique, a general strategy of solving continuous problems by cycling between coarser and finer levels of discretization is described. It provides very fast general solvers, together with adaptive, nearly optimal discretization schemes. In the process, boundary layers are automatically either resolved or skipped, depending on a control function which expresses the computational goal. The global error decreases exponentially as a function of the overall computational work, in a uniform rate independent of the magnitude of the singular-perturbation terms. The key is high-order uniformly stable difference equations, and uniformly smoothing relaxation schemes.

  16. Computational efficiency and Amdahl’s law for the adaptive resolution simulation technique

    DOE PAGES

    Junghans, Christoph; Agarwal, Animesh; Delle Site, Luigi

    2017-06-01

    Here, we discuss the computational performance of the adaptive resolution technique in molecular simulation when it is compared with equivalent full coarse-grained and full atomistic simulations. We show that an estimate of its efficiency, within 10%–15% accuracy, is given by the Amdahl’s Law adapted to the specific quantities involved in the problem. The derivation of the predictive formula is general enough that it may be applied to the general case of molecular dynamics approaches where a reduction of degrees of freedom in a multi scale fashion occurs.

  17. An Adaptive Technique for a Redundant-Sensor Navigation System. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Chien, T. T.

    1972-01-01

    An on-line adaptive technique is developed to provide a self-contained redundant-sensor navigation system with a capability to utilize its full potentiality in reliability and performance. The gyro navigation system is modeled as a Gauss-Markov process, with degradation modes defined as changes in characteristics specified by parameters associated with the model. The adaptive system is formulated as a multistage stochastic process: (1) a detection system, (2) an identification system and (3) a compensation system. It is shown that the sufficient statistics for the partially observable process in the detection and identification system is the posterior measure of the state of degradation, conditioned on the measurement history.

  18. Computational efficiency and Amdahl's law for the adaptive resolution simulation technique

    NASA Astrophysics Data System (ADS)

    Junghans, Christoph; Agarwal, Animesh; Delle Site, Luigi

    2017-06-01

    We discuss the computational performance of the adaptive resolution technique in molecular simulation when it is compared with equivalent full coarse-grained and full atomistic simulations. We show that an estimate of its efficiency, within 10%-15% accuracy, is given by the Amdahl's Law adapted to the specific quantities involved in the problem. The derivation of the predictive formula is general enough that it may be applied to the general case of molecular dynamics approaches where a reduction of degrees of freedom in a multiscale fashion occurs.

  19. Key techniques and applications of adaptive growth method for stiffener layout design of plates and shells

    NASA Astrophysics Data System (ADS)

    Ding, Xiaohong; Ji, Xuerong; Ma, Man; Hou, Jianyun

    2013-11-01

    The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure construction and seed selection are studied, so as to make it possible to improve the effectiveness and applicability of the adaptive growth method in stiffener layout design optimization of plates and shells. Three schemes of ground structures, which are comprised by different shell elements and beam elements, are proposed. It is found that the main stiffener layouts resulted from different ground structures are almost the same, but the ground structure comprised by 8-nodes shell elements and both 3-nodes and 2-nodes beam elements can result in clearest stiffener layout, and has good adaptability and low computational cost. An automatic seed selection approach is proposed, which is based on such selection rules that the seeds should be positioned on where the structural strain energy is great for the minimum compliance problem, and satisfy the dispersancy requirement. The adaptive growth method with the suggested key techniques is integrated into an ANSYS-based program, which provides a design tool for the stiffener layout design optimization of plates and shells. Typical design examples, including plate and shell structures to achieve minimum compliance and maximum bulking stability are illustrated. In addition, as a practical mechanical structural design example, the stiffener layout of an inlet structure for a large-scale electrostatic precipitator is also demonstrated. The design results show that the adaptive growth method integrated with the suggested key techniques can effectively and flexibly deal with stiffener layout design problem for plates and shells with complex geometrical shape and loading conditions to achieve various design objectives, thus it provides a new solution method for engineering structural topology design optimization.

  20. Marginal adaptation and CAD-CAM technology: A systematic review of restorative material and fabrication techniques.

    PubMed

    Papadiochou, Sofia; Pissiotis, Argirios L

    2017-09-27

    The comparative assessment of computer-aided design and computer-aided manufacturing (CAD-CAM) technology and other fabrication techniques pertaining to marginal adaptation should be documented. Limited evidence exists on the effect of restorative material on the performance of a CAD-CAM system relative to marginal adaptation. The purpose of this systematic review was to investigate whether the marginal adaptation of CAD-CAM single crowns, fixed dental prostheses, and implant-retained fixed dental prostheses or their infrastructures differs from that obtained by other fabrication techniques using a similar restorative material and whether it depends on the type of restorative material. An electronic search of English-language literature published between January 1, 2000, and June 30, 2016, was conducted of the Medline/PubMed database. Of the 55 included comparative studies, 28 compared CAD-CAM technology with conventional fabrication techniques, 12 contrasted CAD-CAM technology and copy milling, 4 compared CAD-CAM milling with direct metal laser sintering (DMLS), and 22 investigated the performance of a CAD-CAM system regarding marginal adaptation in restorations/infrastructures produced with different restorative materials. Most of the CAD-CAM restorations/infrastructures were within the clinically acceptable marginal discrepancy (MD) range. The performance of a CAD-CAM system relative to marginal adaptation is influenced by the restorative material. Compared with CAD-CAM, most of the heat-pressed lithium disilicate crowns displayed equal or smaller MD values. Slip-casting crowns exhibited similar or better marginal accuracy than those fabricated with CAD-CAM. Cobalt-chromium and titanium implant infrastructures produced using a CAD-CAM system elicited smaller MD values than zirconia. The majority of cobalt-chromium restorations/infrastructures produced by DMLS displayed better marginal accuracy than those fabricated with the casting technique. Compared with copy

  1. Three decision-making aids: brainstorming, nominal group, and Delphi technique.

    PubMed

    McMurray, A R

    1994-01-01

    The methods of brainstorming, Nominal Group Technique, and the Delphi technique can be important resources for nursing staff development educators who wish to expand their decision-making skills. Staff development educators may find opportunities to use these methods for such tasks as developing courses, setting departmental goals, and forecasting trends for planning purposes. Brainstorming, Nominal Group Technique, and the Delphi technique provide a structured format that helps increase the quantity and quality of participant responses.

  2. Mixed-gender groups: coping strategies and factors of psychological adaptation in a polar environment.

    PubMed

    Rosnet, Elisabeth; Jurion, Sylvie; Cazes, Geneviève; Bachelard, Claude

    2004-07-01

    The polar environment is often seen as a good analog for long-term space missions in terms of isolation and confinement. This paper focuses on the psychological adaptation of both the men and women in mixed-gender groups in the French polar station Dumont d'Urville. The first 49 expeditions to this station were composed of men only in groups of 25-30. In 2000, two women were included in the first mixed-gender wintering group, followed by five women in 2001. This study on coping strategies and psychological adaptation was included in an end-of-mission debriefing performed by a psychologist. Data were collected using a few quantitative tools and a semi-structured interview, and focused on adaptation to wintering, coping strategies, and information on interpersonal relationships. Including women in a wintering group seems to have had positive effects on the general climate of the group by reducing men's rude behavior, but it also seems to be an important stressor for both men and women when the females' average age is close to the males' because seduction behaviors appear and rivalry, frustration, and sexual harassment frequently result. The use of problem-oriented strategies helps women to adapt. There are strong arguments indicating that living in an isolated and confined environment magnifies the usual difficulties that arise in mixed-gender relationships. Difficulties may be magnified in space since the group size is smaller and the confinement more extreme. This implies the need for rigorous select-in criteria for both men and women, especially for relational criteria, and for group training after selection.

  3. Stable adaptive PI control for permanent magnet synchronous motor drive based on improved JITL technique.

    PubMed

    Zheng, Shiqi; Tang, Xiaoqi; Song, Bao; Lu, Shaowu; Ye, Bosheng

    2013-07-01

    In this paper, a stable adaptive PI control strategy based on the improved just-in-time learning (IJITL) technique is proposed for permanent magnet synchronous motor (PMSM) drive. Firstly, the traditional JITL technique is improved. The new IJITL technique has less computational burden and is more suitable for online identification of the PMSM drive system which is highly real-time compared to traditional JITL. In this way, the PMSM drive system is identified by IJITL technique, which provides information to an adaptive PI controller. Secondly, the adaptive PI controller is designed in discrete time domain which is composed of a PI controller and a supervisory controller. The PI controller is capable of automatically online tuning the control gains based on the gradient descent method and the supervisory controller is developed to eliminate the effect of the approximation error introduced by the PI controller upon the system stability in the Lyapunov sense. Finally, experimental results on the PMSM drive system show accurate identification and favorable tracking performance.

  4. Adaptive remeshing method in 2D based on refinement and coarsening techniques

    NASA Astrophysics Data System (ADS)

    Giraud-Moreau, L.; Borouchaki, H.; Cherouat, A.

    2007-04-01

    The analysis of mechanical structures using the Finite Element Method, in the framework of large elastoplastic strains, needs frequent remeshing of the deformed domain during computation. Remeshing is necessary for two main reasons, the large geometric distortion of finite elements and the adaptation of the mesh size to the physical behavior of the solution. This paper presents an adaptive remeshing method to remesh a mechanical structure in two dimensions subjected to large elastoplastic deformations with damage. The proposed remeshing technique includes adaptive refinement and coarsening procedures, based on geometrical and physical criteria. The proposed method has been integrated in a computational environment using the ABAQUS solver. Numerical examples show the efficiency of the proposed approach.

  5. A high-performance angular speed measurement method based on adaptive hysteresis switching techniques

    NASA Astrophysics Data System (ADS)

    Huang, Haiming; Chou, Wusheng; Zhang, Zuojiang

    2015-12-01

    The high-performance measurement of angular speed (AS) is an essential requirement for achieving the high accuracy of machine control and monitoring. This paper proposes a new adaptive AS measurement system, which minimizes AS errors and fluctuations from conventional AS methods in a wide range of AS measurement. Unlike the conventional switches used previously, the system is composed of two layers of hysteresis switches, hereinafter referred to as the inner and outer hysteresis switch, respectively, to count pulses from an optical encoder adaptively. To highlight the key techniques used, the system is named as a hysteresis switch-based adaptation AS measurement (HS-AASM). The proposed method is designed and implemented based on a cost-effective TMS320F28335 digital signal controller (DSC). The performance analyses and experimental verifications show that the HS-AASM method outperforms the existing methods.

  6. General adaptive-neighborhood technique for improving synthetic aperture radar interferometric coherence estimation.

    PubMed

    Vasile, Gabriel; Trouvé, Emmanuel; Ciuc, Mihai; Buzuloiu, Vasile

    2004-08-01

    A new method for filtering the coherence map issued from synthetic aperture radar (SAR) interferometric data is presented. For each pixel of the interferogram, an adaptive neighborhood is determined by a region-growing technique driven by the information provided by the amplitude images. Then pixels in the derived adaptive neighborhood are complex averaged to yield the filtered value of the coherence, after a phase-compensation step is performed. An extension of the algorithm is proposed for polarimetric interferometric SAR images. The proposed method has been applied to both European Remote Sensing (ERS) satellite SAR images and airborne high-resolution polarimetric interferometric SAR images. Both subjective and objective performance analysis, including coherence edge detection, shows that the proposed method provides better results than the standard phase-compensated fixed multilook filter and the Lee adaptive coherence filter.

  7. Grid and basis adaptive polynomial chaos techniques for sensitivity and uncertainty analysis

    SciTech Connect

    Perkó, Zoltán Gilli, Luca Lathouwers, Danny Kloosterman, Jan Leen

    2014-03-01

    The demand for accurate and computationally affordable sensitivity and uncertainty techniques is constantly on the rise and has become especially pressing in the nuclear field with the shift to Best Estimate Plus Uncertainty methodologies in the licensing of nuclear installations. Besides traditional, already well developed methods – such as first order perturbation theory or Monte Carlo sampling – Polynomial Chaos Expansion (PCE) has been given a growing emphasis in recent years due to its simple application and good performance. This paper presents new developments of the research done at TU Delft on such Polynomial Chaos (PC) techniques. Our work is focused on the Non-Intrusive Spectral Projection (NISP) approach and adaptive methods for building the PCE of responses of interest. Recent efforts resulted in a new adaptive sparse grid algorithm designed for estimating the PC coefficients. The algorithm is based on Gerstner's procedure for calculating multi-dimensional integrals but proves to be computationally significantly cheaper, while at the same it retains a similar accuracy as the original method. More importantly the issue of basis adaptivity has been investigated and two techniques have been implemented for constructing the sparse PCE of quantities of interest. Not using the traditional full PC basis set leads to further reduction in computational time since the high order grids necessary for accurately estimating the near zero expansion coefficients of polynomial basis vectors not needed in the PCE can be excluded from the calculation. Moreover the sparse PC representation of the response is easier to handle when used for sensitivity analysis or uncertainty propagation due to the smaller number of basis vectors. The developed grid and basis adaptive methods have been implemented in Matlab as the Fully Adaptive Non-Intrusive Spectral Projection (FANISP) algorithm and were tested on four analytical problems. These show consistent good performance both

  8. Adaptive data rate control TDMA systems as a rain attenuation compensation technique

    NASA Technical Reports Server (NTRS)

    Sato, Masaki; Wakana, Hiromitsu; Takahashi, Takashi; Takeuchi, Makoto; Yamamoto, Minoru

    1993-01-01

    Rainfall attenuation has a severe effect on signal strength and impairs communication links for future mobile and personal satellite communications using Ka-band and millimeter wave frequencies. As rain attenuation compensation techniques, several methods such as uplink power control, site diversity, and adaptive control of data rate or forward error correction have been proposed. In this paper, we propose a TDMA system that can compensate rain attenuation by adaptive control of transmission rates. To evaluate the performance of this TDMA terminal, we carried out three types of experiments: experiments using a Japanese CS-3 satellite with Ka-band transponders, in house IF loop-back experiments, and computer simulations. Experimental results show that this TDMA system has advantages over the conventional constant-rate TDMA systems, as resource sharing technique, in both bit error rate and total TDMA burst lengths required for transmitting given information.

  9. Use of an inelastic bandage as an adaptation of the lymphatic drainage technique in lower limbs

    PubMed Central

    Fregonezi, Guilherme; Resqueti, Vanessa; Ferreira, Socorro; Lima, Ana Paula

    2009-01-01

    The inelastic bandage is an adaptation of the manual lymphatic drainage, which substitutes the circular movements of the fingers. A patient with lymphoedema underwent 20 sessions using the modified lymphatic drainage technique. Perimetric measurements were taken before and after each session, and volumetric measurements at the first, 10th, and 20th sessions. Limb circumference was significantly reduced at three points on the perimeter (10, 15 and 25 cm): 2.5 cm (7.3%), 2.5 cm (6.5%) and 1.5 cm (5%), respectively. Volumetry decrease of 26.4% from initial limb volume was observed. The use of the inelastic bandage proved to be an effective adaptation when compared with the results using other techniques described. PMID:21686946

  10. Development of a clinical pathways analysis system with adaptive Bayesian nets and data mining techniques.

    PubMed

    Kopec, D; Shagas, G; Reinharth, D; Tamang, S

    2004-01-01

    The use and development of software in the medical field offers tremendous opportunities for making health care delivery more efficient, more effective, and less error-prone. We discuss and explore the use of clinical pathways analysis with Adaptive Bayesian Networks and Data Mining Techniques to perform such analyses. The computation of "lift" (a measure of completed pathways improvement potential) leads us to optimism regarding the potential for this approach.

  11. Minimal stochastic complexity snake-based technique adapted to an unknown noise model

    NASA Astrophysics Data System (ADS)

    Galland, Fré; Déric; Réfrégier, Philippe

    2005-09-01

    We propose a polygonal snake segmentation technique adapted to objects that can be composed of several regions with gray-level fluctuations described by a priori unknown probability laws. This approach is based on a histogram equalization and on the minimization of a criterion without parameter to be tuned by the user. We demonstrate the efficiency of this approach, which has low computational cost, on synthetic and real images perturbed by different types of optical noise.

  12. Cytological techniques to analyze meiosis in Arabidopsis arenosa for investigating adaptation to polyploidy.

    PubMed

    Higgins, James D; Wright, Kevin M; Bomblies, Kirsten; Franklin, F Chris H

    2014-01-01

    Arabidopsis arenosa is a close relative of the model plant A. thaliana, and exists in nature as stable diploid and autotetraploid populations. Natural tetraploids have adapted to whole genome duplication and do not commonly show meiotic errors such as multivalent and univalent formation, which can lead to chromosome non-disjunction and reduced fertility. A genome scan for genes strongly differentiated between diploid and autotetraploid A. arenosa identified a subset of meiotic genes that may be responsible for adaptation to polyploid meiosis. To investigate the mechanisms by which A. arenosa adapted to its polyploid state, and the functionality of the identified potentially adaptive polymorphisms, a thorough cytological analysis is required. Therefore, in this chapter we describe methods and techniques to analyze male meiosis in A. arenosa, including optimum plant growth conditions, and immunocytological and cytological approaches developed with the specific purpose of understanding meiotic adaptation in an autotetraploid. In addition we present a meiotic cytological atlas to be used as a reference for particular stages and discuss observations arising from a comparison of meiosis between diploid and autotetraploid A. arenosa.

  13. Robust control for a biaxial servo with time delay system based on adaptive tuning technique.

    PubMed

    Chen, Tien-Chi; Yu, Chih-Hsien

    2009-07-01

    A robust control method for synchronizing a biaxial servo system motion is proposed in this paper. A new network based cross-coupled control and adaptive tuning techniques are used together to cancel out the skew error. The conventional fixed gain PID cross-coupled controller (CCC) is replaced with the adaptive cross-coupled controller (ACCC) in the proposed control scheme to maintain biaxial servo system synchronization motion. Adaptive-tuning PID (APID) position and velocity controllers provide the necessary control actions to maintain synchronization while following a variable command trajectory. A delay-time compensator (DTC) with an adaptive controller was augmented to set the time delay element, effectively moving it outside the closed loop, enhancing the stability of the robust controlled system. This scheme provides strong robustness with respect to uncertain dynamics and disturbances. The simulation and experimental results reveal that the proposed control structure adapts to a wide range of operating conditions and provides promising results under parameter variations and load changes.

  14. Denoising techniques in adaptive multi-resolution domains with applications to biomedical images.

    PubMed

    Lahmiri, Salim

    2017-02-01

    Variational mode decomposition (VMD) is a new adaptive multi-resolution technique suitable for signal denoising purpose. The main focus of this work has been to study the feasibility of several image denoising techniques in empirical mode decomposition (EMD) and VMD domains. A comparative study is made using 11 techniques widely used in the literature, including Wiener filter, first-order local statistics, fourth partial differential equation, nonlinear complex diffusion process, linear complex diffusion process (LCDP), probabilistic non-local means, non-local Euclidean medians, non-local means, non-local patch regression, discrete wavelet transform and wavelet packet transform. On the basis of comparison of 396 denoising based on peak signal-to-noise ratio, it is found that the best performances are obtained in VMD domain when appropriate denoising techniques are applied. Particularly, it is found that LCDP in combination with VMD performs the best and that VMD is faster than EMD.

  15. Comparison of online IGRT techniques for prostate IMRT treatment: Adaptive vs repositioning correction

    SciTech Connect

    Thongphiew, Danthai; Wu, Q. Jackie; Lee, W. Robert; Chankong, Vira; Yoo, Sua; McMahon, Ryan; Yin Fangfang

    2009-05-15

    This study compares three online image guidance techniques (IGRT) for prostate IMRT treatment: bony-anatomy matching, soft-tissue matching, and online replanning. Six prostate IMRT patients were studied. Five daily CBCT scans from the first week were acquired for each patient to provide representative ''snapshots'' of anatomical variations during the course of treatment. Initial IMRT plans were designed for each patient with seven coplanar 15 MV beams on a Eclipse treatment planning system. Two plans were created, one with a PTV margin of 10 mm and another with a 5 mm PTV margin. Based on these plans, the delivered dose distributions to each CBCT anatomy was evaluated to compare bony-anatomy matching, soft-tissue matching, and online replanning. Matching based on bony anatomy was evaluated using the 10 mm PTV margin (''bone10''). Soft-tissue matching was evaluated using both the 10 mm (''soft10'') and 5 mm (''soft5'') PTV margins. Online reoptimization was evaluated using the 5 mm PTV margin (''adapt''). The replanning process utilized the original dose distribution as the basis and linear goal programming techniques for reoptimization. The reoptimized plans were finished in less than 2 min for all cases. Using each IGRT technique, the delivered dose distribution was evaluated on all 30 CBCT scans (6 patientsx5CBCT/patient). The mean minimum dose (in percentage of prescription dose) to the CTV over five treatment fractions were in the ranges of 99%-100%(SD=0.1%-0.8%), 65%-98%(SD=0.4%-19.5%), 87%-99%(SD=0.7%-23.3%), and 95%-99%(SD=0.4%-10.4%) for the adapt, bone10, soft5, and soft10 techniques, respectively. Compared to patient position correction techniques, the online reoptimization technique also showed improvement in OAR sparing when organ motion/deformations were large. For bladder, the adapt technique had the best (minimum) D90, D50, and D30 values for 24, 17, and 15 fractions out of 30 total fractions, while it also had the best D90, D50, and D30 values for

  16. An Adaptive Image Enhancement Technique by Combining Cuckoo Search and Particle Swarm Optimization Algorithm

    PubMed Central

    Ye, Zhiwei; Wang, Mingwei; Hu, Zhengbing; Liu, Wei

    2015-01-01

    Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO) for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper. PMID:25784928

  17. An adaptive image enhancement technique by combining cuckoo search and particle swarm optimization algorithm.

    PubMed

    Ye, Zhiwei; Wang, Mingwei; Hu, Zhengbing; Liu, Wei

    2015-01-01

    Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO) for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper.

  18. An Autonomous Self-Aware and Adaptive Fault Tolerant Routing Technique for Wireless Sensor Networks

    PubMed Central

    Abba, Sani; Lee, Jeong-A

    2015-01-01

    We propose an autonomous self-aware and adaptive fault-tolerant routing technique (ASAART) for wireless sensor networks. We address the limitations of self-healing routing (SHR) and self-selective routing (SSR) techniques for routing sensor data. We also examine the integration of autonomic self-aware and adaptive fault detection and resiliency techniques for route formation and route repair to provide resilience to errors and failures. We achieved this by using a combined continuous and slotted prioritized transmission back-off delay to obtain local and global network state information, as well as multiple random functions for attaining faster routing convergence and reliable route repair despite transient and permanent node failure rates and efficient adaptation to instantaneous network topology changes. The results of simulations based on a comparison of the ASAART with the SHR and SSR protocols for five different simulated scenarios in the presence of transient and permanent node failure rates exhibit a greater resiliency to errors and failure and better routing performance in terms of the number of successfully delivered network packets, end-to-end delay, delivered MAC layer packets, packet error rate, as well as efficient energy conservation in a highly congested, faulty, and scalable sensor network. PMID:26295236

  19. Wavelet neural network control for linear ultrasonic motor drive via adaptive sliding-mode technique.

    PubMed

    Lin, Faa-Jeng; Wai, Rong-Jong; Chen, Mu-Ping

    2003-06-01

    A wavelet neural network (WNN) control system is proposed to control the moving table of a linear ultrasonic motor (LUSM) drive system to track periodic reference trajectories in this study. The design of the WNN control system is based on an adaptive sliding-mode control technique. The structure and operating principle of the LUSM are introduced, and the driving circuit of the LUSM, which is a voltage source inverter using two-inductance two capacitance (LLCC) resonant technique, is introduced. Because the dynamic characteristics and motor parameters of the LUSM are nonlinear and time varying, a WNN control system is designed based on adaptive sliding-mode control technique to achieve precision position control. In the WNN control system, a WNN is used to learn the ideal equivalent control law, and a robust controller is designed to meet the sliding condition. Moreover, the adaptive learning algorithms of the WNN and the bound estimation algorithm of the robust controller are derived from the sense of Lyapunov stability analysis. The effectiveness of the proposed WNN control system is verified by some experimental results in the presence of uncertainties.

  20. [Application of adaptive iterative dose reduction technique in CT enterography in diagnosing Crohn disease].

    PubMed

    Lian, Yanbang; Cao, Wuteng; Zhu, Shanshan; Lin, Yanghao; Liu, Dechao; Wang, Xinhua; Qiu, Jianping; Zhou, Zhiyang

    2014-07-01

    To evaluate the application of low-dose CT enterography with adaptive iterative dose reduction(AIDR) technique in diagnosing Crohn's disease. Retrospective analysis was performed on 26 patients diagnosed as Crohn's disease by the multidisciplinary team in our hospital. Low-dose CT enterography with 640-slice MDCT was performed on these 26 patients using adaptive iterative dose reduction(AIDR) technique. Characteristics of Crohn's disease in CT enterography images were independently analyzed by two radiologists who were experienced in Crohn's disease with calculating the total radiation dosage. The radiation dosage of 26 patients ranged from 5.58 to 12.90 [mean (9.00±2.00)] mSv, which was lower than conventional scan (around 15 mSv) known from the literatures. According to the images of CT enterography of 26 cases, bowel wall thickening with abnormal enhancement and lymphadenectasis were found in 25 cases with total 109 segmental bowel wall thickening. Among 25 thickening cases, enterostenosis was found in 16 cases, stratification enhancement in 12 cases and comb sign in 14 cases. Besides, it was found that 8 cases with hyperdense fat on the mesenteric side, 7 cases with intestinal fistula, 6 cases with abdominal cavity abscess, and 3 cases with anal fistula. CT enterography of Crohn's disease with adaptive iterative dose reduction technique is an effective method to evaluate Crohn's disease without compromising image quality with reduced radiation dosage.

  1. Chemical Assignment of Symmetry-Adapted Perturbation Theory Interaction Energy Components: The Functional-Group SAPT Partition.

    PubMed

    Parrish, Robert M; Parker, Trent M; Sherrill, C David

    2014-10-14

    Recently, we introduced an effective atom-pairwise partition of the many-body symmetry-adapted perturbation theory (SAPT) interaction energy decomposition, producing a method known as atomic SAPT (A-SAPT) [Parrish, R. M.; Sherrill, C. D. J. Chem. Phys. 2014, 141, 044115]. A-SAPT provides ab initio atom-pair potentials for force field development and also automatic visualizations of the spatial contributions of noncovalent interactions, but often has difficulty producing chemically useful partitions of the electrostatic energy, due to the buildup of oscillating partial charges on adjacent functional groups. In this work, we substitute chemical functional groups in place of atoms as the relevant local quasiparticles in the partition, resulting in a functional-group-pairwise partition denoted as functional-group SAPT (F-SAPT). F-SAPT assigns integral sets of local occupied electronic orbitals and protons to chemical functional groups and linking σ bonds. Link-bond contributions can be further assigned to chemical functional groups to simplify the analysis. This approach yields a SAPT partition between pairs of functional groups with integral charge (usually neutral), preventing oscillations in the electrostatic partition. F-SAPT qualitatively matches chemical intuition and the cut-and-cap fragmentation technique but additionally yields the quantitative many-body SAPT interaction energy. The conceptual simplicity, chemical utility, and computational efficiency of F-SAPT is demonstrated in the context of phenol dimer, proflavine(+)-DNA intercalation, and a cucurbituril host-guest inclusion complex.

  2. Adaptive meshing technique applied to an orthopaedic finite element contact problem.

    PubMed

    Roarty, Colleen M; Grosland, Nicole M

    2004-01-01

    Finite element methods have been applied extensively and with much success in the analysis of orthopaedic implants. Recently a growing interest has developed, in the orthopaedic biomechanics community, in how numerical models can be constructed for the optimal solution of problems in contact mechanics. New developments in this area are of paramount importance in the design of improved implants for orthopaedic surgery. Finite element and other computational techniques are widely applied in the analysis and design of hip and knee implants, with additional joints (ankle, shoulder, wrist) attracting increased attention. The objective of this investigation was to develop a simplified adaptive meshing scheme to facilitate the finite element analysis of a dual-curvature total wrist implant. Using currently available software, the analyst has great flexibility in mesh generation, but must prescribe element sizes and refinement schemes throughout the domain of interest. Unfortunately, it is often difficult to predict in advance a mesh spacing that will give acceptable results. Adaptive finite-element mesh capabilities operate to continuously refine the mesh to improve accuracy where it is required, with minimal intervention by the analyst. Such mesh adaptation generally means that in certain areas of the analysis domain, the size of the elements is decreased (or increased) and/or the order of the elements may be increased (or decreased). In concept, mesh adaptation is very appealing. Although there have been several previous applications of adaptive meshing for in-house FE codes, we have coupled an adaptive mesh formulation with the pre-existing commercial programs PATRAN (MacNeal-Schwendler Corp., USA) and ABAQUS (Hibbit Karlson and Sorensen, Pawtucket, RI). In doing so, we have retained several attributes of the commercial software, which are very attractive for orthopaedic implant applications.

  3. Sealing ability and adaptation of root-end filling materials in cavities prepared with different techniques.

    PubMed

    Küçükkaya Eren, Selen; Görduysus, Mehmet Ömer; Şahin, Cem

    2017-03-08

    The aim of this study was to evaluate the sealing ability and marginal adaptation of calcium silicate-based cements (CSCs) in root-end cavities prepared by ultrasonic and laser tips. A total of 72 extracted human maxillary incisor teeth were randomly divided as 60 teeth in experimental groups and 6 teeth each for positive and negative control groups. Specimens in experimental groups were obturated, their root-end resections were performed and randomly divided into six groups (n = 10) as follows: G1: Ultrasonic retrotip + MTA, G2: Ultrasonic retrotip + Calcium Enriched Mixture (CEM), G3: Ultrasonic retrotip + Biodentine, G4: Er:YAG laser tip + MTA, G5: Er:YAG laser tip + CEM, G6: Er:YAG laser tip + Biodentine. The sealing ability was measured by fluid transport method. Six specimens from each experimental group were randomly selected to analyze marginal adaptation and prepared for scanning electron microscopy (SEM) analysis. Micrographs were scored and also analyzed using Image J software. Data were analyzed with; two-way ANOVA, Bonferroni, Kruskall-Wallis, Mann-Whitney-U, Siegel & Castellan, and Spearman correlation coefficient tests. No significant difference was found between materials regarding the sealing ability and marginal adaptation (p > 0.05). Significantly greater fluid movement and poor marginal adaptation were seen for materials placed in cavities prepared by laser tips (p < 0.05). Positive correlation was found between the results of scoring and Image J analysis of SEM images (r = 0.596, p < 0.001). Fluid transport method and SEM analysis gave similar results suggesting the use of ultrasonic-retrotips for preparing root-end cavities which are going to be filled with one of these CSCs.

  4. Lithofacies identification using multiple adaptive resonance theory neural networks and group decision expert system

    USGS Publications Warehouse

    Chang, H.-C.; Kopaska-Merkel, D. C.; Chen, H.-C.; Rocky, Durrans S.

    2000-01-01

    Lithofacies identification supplies qualitative information about rocks. Lithofacies represent rock textures and are important components of hydrocarbon reservoir description. Traditional techniques of lithofacies identification from core data are costly and different geologists may provide different interpretations. In this paper, we present a low-cost intelligent system consisting of three adaptive resonance theory neural networks and a rule-based expert system to consistently and objectively identify lithofacies from well-log data. The input data are altered into different forms representing different perspectives of observation of lithofacies. Each form of input is processed by a different adaptive resonance theory neural network. Among these three adaptive resonance theory neural networks, one neural network processes the raw continuous data, another processes categorial data, and the third processes fuzzy-set data. Outputs from these three networks are then combined by the expert system using fuzzy inference to determine to which facies the input data should be assigned. Rules are prioritized to emphasize the importance of firing order. This new approach combines the learning ability of neural networks, the adaptability of fuzzy logic, and the expertise of geologists to infer facies of the rocks. This approach is applied to the Appleton Field, an oil field located in Escambia County, Alabama. The hybrid intelligence system predicts lithofacies identity from log data with 87.6% accuracy. This prediction is more accurate than those of single adaptive resonance theory networks, 79.3%, 68.0% and 66.0%, using raw, fuzzy-set, and categorical data, respectively, and by an error-backpropagation neural network, 57.3%. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.

  5. Demography-based adaptive network model reproduces the spatial organization of human linguistic groups.

    PubMed

    Capitán, José A; Manrubia, Susanna

    2015-12-01

    The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space.

  6. Demography-based adaptive network model reproduces the spatial organization of human linguistic groups

    NASA Astrophysics Data System (ADS)

    Capitán, José A.; Manrubia, Susanna

    2015-12-01

    The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space.

  7. Persistence of a dominant bovine lineage of group B Streptococcus reveals genomic signatures of host adaptation.

    PubMed

    Almeida, Alexandre; Alves-Barroco, Cinthia; Sauvage, Elisabeth; Bexiga, Ricardo; Albuquerque, Pedro; Tavares, Fernando; Santos-Sanches, Ilda; Glaser, Philippe

    2016-11-01

    Group B Streptococcus (GBS) is a host-generalist species, most notably causing disease in humans and cattle. However, the differential adaptation of GBS to its two main hosts, and the risk of animal to human infection remain poorly understood. Despite improvements in control measures across Europe, GBS is still one of the main causative agents of bovine mastitis in Portugal. Here, by whole-genome analysis of 150 bovine GBS isolates we discovered that a single CC61 clone is spreading throughout Portuguese herds since at least the early 1990s, having virtually replaced the previous GBS population. Mutations within an iron/manganese transporter were independently acquired by all of the CC61 isolates, underlining a key adaptive strategy to persist in the bovine host. Lateral transfer of bacteriocin production and antibiotic resistance genes also underscored the contribution of the microbial ecology and genetic pool within the bovine udder environment to the success of this clone. Compared to strains of human origin, GBS evolves twice as fast in bovines and undergoes recurrent pseudogenizations of human-adapted traits. Our work provides new insights into the potentially irreversible adaptation of GBS to the bovine environment.

  8. Restoring the interproximal zone using the proximal adaptation technique--Part 2.

    PubMed

    Terry, Douglas A

    2005-01-01

    In this era of modern adhesive dentistry, clinicians are still faced with challenges from microleakage, recurrent decay, and sensitivity. Many of the challenges are a result of using yesterday's restorative techniques and principles with the new formulations of biomaterials. Procedures such as the proximal adaptation and the oblique layering techniques offer modifications to the nonadhesive principles discussed in Part I (The Compendium, December 2004), while providing the patient and clinician with the 3 primary objectives of restorative dentistry: prevention, preservation, and conservation. Using stratification techniques and thorough adhesive protocol as illustrated in this article allows clinicians to provide restorations that have improved physical characteristics while reducing the effects of polymerization shrinkage. Other benefits of these adhesive procedures include enhanced chromatic integration, ideal anatomical form and function, optimal proximal contact, improved marginal integrity, and longer lasting directly placed composite restorations.

  9. A assessment of the plastic Thermafil obturation technique. Part 1. Radiographic evaluation of adaptation and placement.

    PubMed

    Gutmann, J L; Saunders, W P; Saunders, E M; Nguyen, L

    1993-05-01

    Adaptation and placement of alpha-phase gutta-percha delivered with a plastic core-carrier, Thermafil, was compared to the lateral condensation of gutta-percha in a specific tooth model. Fifty-one mandibular molar roots with separate canals, patent canal orifices and curvatures greater than 15 degrees were cleaned and shaped with K-files and 2.5% sodium hypochlorite to a size 30 at the apex, and flared with Hedstrom files to create a continuously tapering funnel preparation. Canals were randomly obturated with Sealapex root canal sealer and either alpha-phase gutta-percha on a plastic Thermafil carrier, or standard beta-phase gutta-percha with lateral condensation. Roots were radiographed from the proximal and evaluated by three examiners, based on established criteria for overall material adaptation, apical adaptation, and filling material extrusion. Thermafil provided a statistically significant better overall canal obturation (P < 0.001), while, in the apical third, both techniques were not significantly different (P > 0.05). When the apical orifice was patent there was a significant propensity for the extrusion of filling materials beyond the apex (P < 0.001) with the Thermafil technique.

  10. An adaptive fuzzy-neural-network controller for ultrasonic motor drive using the LLCC resonant technique.

    PubMed

    Lin, F J; Wai, R J; Lin, H H

    1999-01-01

    In this study an adaptive fuzzy-neural-network controller (AFNNC) is proposed to control a rotary traveling wave-type ultrasonic motor (USM) drive system. The USM is derived by a newly designed, high frequency, two-phase voltage source inverter using two inductances and two capacitances (LLCC) resonant technique. Then, because the dynamic characteristics of the USM are complicated and the motor parameters are time varying, an AFNNC is proposed to control the rotor position of the USM. In the proposed controller, the USM drive system is identified by a fuzzy-neural-network identifier (FNNI) to provide the sensitivity information of the drive system to an adaptive controller. The backpropagation algorithm is used to train the FNNI on line. Moreover, to guarantee the convergence of identification and tracking errors, analytical methods based on a discrete-type Lyapunov function are proposed to determine the varied learning rates of the FNNI and the optimal learning rate of the adaptive controller. In addition, the effectiveness of the adaptive fuzzy-neural-network (AFNN) controlled USM drive system is demonstrated by some experimental results.

  11. 76 FR 47237 - Notice of Public Meeting for the Glen Canyon Dam Adaptive Management Work Group Federal Advisory...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ... Bureau of Reclamation Notice of Public Meeting for the Glen Canyon Dam Adaptive Management Work Group... Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations and other management actions to protect resources downstream of Glen...

  12. A simple focal-length measurement technique for adaptive microlenses using z-scan

    NASA Astrophysics Data System (ADS)

    Abdelaziez, Yasser; Banerjee, Partha P.

    2004-10-01

    A simple technique for focal length measurements of adaptive micro-lenses using z-scan is reported. Focal length is one of the most important parameters of any lens. The effective focal length is measured with reference to the principal points that are not easy to find especially for micro-lenses. In addition, variable focal length microlenses pose a different challenge that makes the process of determining their exact focal length a tedious and difficult process. Classical methods such as nodal slide and magnification have been used for focal length determination. Also, advanced Interference techniques such as Talbot, Moire, Digital Speckle, Zygo and Joint Fourier Transform were used for focal length measurements. These techniques require more elaborate setups and difficult to implement, especially for microlenses. Recently a power meter was used to find the focal length of an unknown lens. Most of the techniques mentioned above proof to be not simple for microlens characterization. The z-scan technique has been implemented, for quite sometimes, to characterize the third-order effects of a nonlinear optical material. The z-scan provides information on both the sign and magnitude of the non-linear refractive index and offer advantage of simplicity. We have used a regular lens to collimate and focus light unto the lens under test. By scanning the lens under test and measuring the on-axis intensity, one can find the focal length. This is because the on-axis intensity is proportional to the phase of the lens and therefore the focal length. In the case of an adaptive lens with its focal length is a function of the applied voltage, the scanning occurs for each voltage value that will correspond to the on-axis refractive index change and therefore the far field on-axis intensity. This described technique above is easy to implement and can achieve good accuracy due to the inherent sensitivity of the z-scan.

  13. Comparative Genomic Analysis of the Streptococcus dysgalactiae Species Group: Gene Content, Molecular Adaptation, and Promoter Evolution

    PubMed Central

    Suzuki, Haruo; Lefébure, Tristan; Hubisz, Melissa Jane; Pavinski Bitar, Paulina; Lang, Ping; Siepel, Adam; Stanhope, Michael J.

    2011-01-01

    Comparative genomics of closely related bacterial species with different pathogenesis and host preference can provide a means of identifying the specifics of adaptive differences. Streptococcus dysgalactiae (SD) is comprised of two subspecies: S. dysgalactiae subsp. equisimilis is both a human commensal organism and a human pathogen, and S. dysgalactiae subsp. dysgalactiae is strictly an animal pathogen. Here, we present complete genome sequences for both taxa, with analyses involving other species of Streptococcus but focusing on adaptation in the SD species group. We found little evidence for enrichment in biochemical categories of genes carried by each SD strain, however, differences in the virulence gene repertoire were apparent. Some of the differences could be ascribed to prophage and integrative conjugative elements. We identified approximately 9% of the nonrecombinant core genome to be under positive selection, some of which involved known virulence factors in other bacteria. Analyses of proteomes by pooling data across genes, by biochemical category, clade, or branch, provided evidence for increased rates of evolution in several gene categories, as well as external branches of the tree. Promoters were primarily evolving under purifying selection but with certain categories of genes evolving faster. Many of these fast-evolving categories were the same as those associated with rapid evolution in proteins. Overall, these results suggest that adaptation to changing environments and new hosts in the SD species group has involved the acquisition of key virulence genes along with selection of orthologous protein-coding loci and operon promoters. PMID:21282711

  14. A cost-effective line-based light-balancing technique using adaptive processing.

    PubMed

    Hsia, Shih-Chang; Chen, Ming-Huei; Chen, Yu-Min

    2006-09-01

    The camera imaging system has been widely used; however, the displaying image appears to have an unequal light distribution. This paper presents novel light-balancing techniques to compensate uneven illumination based on adaptive signal processing. For text image processing, first, we estimate the background level and then process each pixel with nonuniform gain. This algorithm can balance the light distribution while keeping a high contrast in the image. For graph image processing, the adaptive section control using piecewise nonlinear gain is proposed to equalize the histogram. Simulations show that the performance of light balance is better than the other methods. Moreover, we employ line-based processing to efficiently reduce the memory requirement and the computational cost to make it applicable in real-time systems.

  15. Forward-Inverse Adaptive Techniques for Reservoir Characterization and Simulation: Theory and Applications

    SciTech Connect

    Doss, S D; Ezzedine, S; Gelinas, R; Chawathe, A

    2001-06-11

    A novel approach called Forward-Inverse Adaptive Techniques (FIAT) for reservoir characterization is developed and applied to three representative exploration cases. Inverse modeling refers to the determination of the entire reservoir permeability under steady state single-phase flow regime, given only field permeability, pressure and production well measurements. FIAT solves the forward and inverse partial differential equations (PDEs) simultaneously by adding a regularization term and filtering pressure gradients. An implicit adaptive-grid, Galerkin, numerical scheme is used to numerically solve the set of PDEs subject to pressure and permeability boundary conditions. Three examples are presented. Results from all three cases demonstrate attainable and reasonably accurate solutions and, more importantly, provide insights into the consequences of data undersampling.

  16. Adapting range migration techniques for imaging with metasurface antennas: analysis and limitations

    NASA Astrophysics Data System (ADS)

    Pulido Mancera, Laura; Fromenteze, Thomas; Sleasman, Timothy; Boyarsky, Michael; Imani, Mohammadreza F.; Reynolds, Matthew S.; Smith, David R.

    2017-04-01

    Dynamic metasurface antennas are planar structures that exhibit remarkable capabilities in controlling electromagnetic wave-fronts, advantages which are particularly attractive for microwave imaging. These antennas exhibit strong frequency dispersion and produce diverse radiation patterns. Such behavior presents unique challenges for integration with conventional imaging algorithms. We analyze an adapted version of the range migration algorithm (RMA) for use with dynamic metasurfaces in image reconstruction. Focusing on the the proposed pre-processing step, that ultimately allows a fast processing of the backscattered signal in the spatial frequency domain from which the fast Fourier transform can efficiently reconstruct the scene. Numerical studies illustrate imaging performance using both conventional methods and the adapted RMA, demonstrating that the RMA can reconstruct images with comparable quality in a fraction of the time. In this paper, we demonstrate the capabilities of the algorithm as a fast reconstruction tool, and we analyze the limitations of the presented technique in terms of image quality.

  17. Multidisciplinary Teams and Group Decision-Making Techniques: Possible Solutions to Decision-Making Problems.

    ERIC Educational Resources Information Center

    Kaiser, Steven M.; Woodman, Richard W.

    1985-01-01

    In placement decisions necessitated by PL 94-142, the multidimensional team approach may be hindered by group problems. The more structured nominal group technique (NGT) is suggested. NGT has six steps: silent, written generation of ideas; round robin reporting; group discussion for clarification; preliminary priority vote; discussion; and final…

  18. Health adaptation policy for climate vulnerable groups: a 'critical computational linguistics' analysis.

    PubMed

    Seidel, Bastian M; Bell, Erica

    2014-11-28

    Many countries are developing or reviewing national adaptation policy for climate change but the extent to which these meet the health needs of vulnerable groups has not been assessed. This study examines the adequacy of such policies for nine known climate-vulnerable groups: people with mental health conditions, Aboriginal people, culturally and linguistically diverse groups, aged people, people with disabilities, rural communities, children, women, and socioeconomically disadvantaged people. The study analyses an exhaustive sample of national adaptation policy documents from Annex 1 ('developed') countries of the United Nations Framework Convention on Climate Change: 20 documents from 12 countries. A 'critical computational linguistics' method was used involving novel software-driven quantitative mapping and traditional critical discourse analysis. The study finds that references to vulnerable groups are relatively little present or non-existent, as well as poorly connected to language about practical strategies and socio-economic contexts, both also little present. The conclusions offer strategies for developing policy that is better informed by a 'social determinants of health' definition of climate vulnerability, consistent with best practice in the literature and global policy prescriptions.

  19. An adaptive distance-based group contribution method for thermodynamic property prediction.

    PubMed

    He, Tanjin; Li, Shuang; Chi, Yawei; Zhang, Hong-Bo; Wang, Zhi; Yang, Bin; He, Xin; You, Xiaoqing

    2016-09-14

    In the search for an accurate yet inexpensive method to predict thermodynamic properties of large hydrocarbon molecules, we have developed an automatic and adaptive distance-based group contribution (DBGC) method. The method characterizes the group interaction within a molecule with an exponential decay function of the group-to-group distance, defined as the number of bonds between the groups. A database containing the molecular bonding information and the standard enthalpy of formation (Hf,298K) for alkanes, alkenes, and their radicals at the M06-2X/def2-TZVP//B3LYP/6-31G(d) level of theory was constructed. Multiple linear regression (MLR) and artificial neural network (ANN) fitting were used to obtain the contributions from individual groups and group interactions for further predictions. Compared with the conventional group additivity (GA) method, the DBGC method predicts Hf,298K for alkanes more accurately using the same training sets. Particularly for some highly branched large hydrocarbons, the discrepancy with the literature data is smaller for the DBGC method than the conventional GA method. When extended to other molecular classes, including alkenes and radicals, the overall accuracy level of this new method is still satisfactory.

  20. Adaptive broadening to improve spectral resolution in the numerical renormalization group

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Sup B.; Weichselbaum, Andreas

    2016-12-01

    We propose an adaptive scheme of broadening the discrete spectral data from numerical renormalization group (NRG) calculations to improve the resolution of dynamical properties at finite energies. While the conventional scheme overbroadens narrow features at large frequency by broadening discrete weights with constant width in log-frequency, our scheme broadens each discrete contribution individually based on its sensitivity to a z -shift in the logarithmic discretization intervals. We demonstrate that the adaptive broadening better resolves various features in noninteracting and interacting models at comparable computational cost. The resolution enhancement is more significant for coarser discretization as typically required in multiband calculations. At low frequency below the energy scale of temperature, the discrete NRG data necessarily needs to be broadened on a linear scale. Here we provide a method that minimizes transition artifacts in between these broadening kernels.

  1. A spatially adaptive spectral re-ordering technique for lossless coding of hyper-spectral images

    NASA Technical Reports Server (NTRS)

    Memon, Nasir D.; Galatsanos, Nikolas

    1995-01-01

    In this paper, we propose a new approach, applicable to lossless compression of hyper-spectral images, that alleviates some limitations of linear prediction as applied to this problem. According to this approach, an adaptive re-ordering of the spectral components of each pixel is performed prior to prediction and encoding. This re-ordering adaptively exploits, on a pixel-by pixel basis, the presence of inter-band correlations for prediction. Furthermore, the proposed approach takes advantage of spatial correlations, and does not introduce any coding overhead to transmit the order of the spectral bands. This is accomplished by using the assumption that two spatially adjacent pixels are expected to have similar spectral relationships. We thus have a simple technique to exploit spectral and spatial correlations in hyper-spectral data sets, leading to compression performance improvements as compared to our previously reported techniques for lossless compression. We also look at some simple error modeling techniques for further exploiting any structure that remains in the prediction residuals prior to entropy coding.

  2. Robust Adaptive Beamforming Based on Low-Rank and Cross-Correlation Techniques

    NASA Astrophysics Data System (ADS)

    Ruan, Hang; de Lamare, Rodrigo C.

    2016-08-01

    This work presents cost-effective low-rank techniques for designing robust adaptive beamforming (RAB) algorithms. The proposed algorithms are based on the exploitation of the cross-correlation between the array observation data and the output of the beamformer. Firstly, we construct a general linear equation considered in large dimensions whose solution yields the steering vector mismatch. Then, we employ the idea of the full orthogonalization method (FOM), an orthogonal Krylov subspace based method, to iteratively estimate the steering vector mismatch in a reduced-dimensional subspace, resulting in the proposed orthogonal Krylov subspace projection mismatch estimation (OKSPME) method. We also devise adaptive algorithms based on stochastic gradient (SG) and conjugate gradient (CG) techniques to update the beamforming weights with low complexity and avoid any costly matrix inversion. The main advantages of the proposed low-rank and mismatch estimation techniques are their cost-effectiveness when dealing with high dimension subspaces or large sensor arrays. Simulations results show excellent performance in terms of the output signal-to-interference-plus-noise ratio (SINR) of the beamformer among all the compared RAB methods.

  3. [Effects of group psychological counseling on self-confidence and social adaptation of burn patients].

    PubMed

    Dang, Rui; Wang, Yishen; Li, Na; He, Ting; Shi, Mengna; Liang, Yanyan; Zhu, Chan; Zhou, Yongbo; Qi, Zongshi; Hu, Dahai

    2014-12-01

    To explore the effects of group psychological counseling on the self-confidence and social adaptation of burn patients during the course of rehabilitation. Sixty-four burn patients conforming to the inclusion criteria and hospitalized from January 2012 to January 2014 in Xijing Hospital were divided into trial group and control group according to the method of rehabilitation, with 32 cases in each group. Patients in the two groups were given ordinary rehabilitation training for 8 weeks, and the patients in trial group were given a course of group psychological counseling in addition. The Rosenberg's Self-Esteem Scale was used to evaluate the changes in self-confidence levels, and the number of patients with inferiority complex, normal feeling, self-confidence, and over self-confidence were counted before and after treatment. The Abbreviated Burn-Specific Health Scale was used to evaluate physical function, psychological function, social relationship, health condition, and general condition before and after treatment to evaluate the social adaptation of patients. Data were processed with t test, chi-square test, Mann-Whitney U test, and Wilcoxon test. (1) After treatment, the self-confidence levels of patients in trial group were significantly higher than those in control group (Z = -2.573, P < 0.05). Among trial group, the number of patients with inferiority complex was 17 (53.1%) before treatment, which was decreased to 6 (18.8%) after treatment; the number of patients with normal feeling and that of self-confidence were 8 (25.0%) and 4 (12.5%) before treatment, which were respectively increased to 13 (40.6%) and 10 (31.3%) after treatment. The overall difference in trial group was obvious between before and after treatment (Z = -4.123, P < 0.01) . There was no obvious difference in self-confidence level of patients in control group between before and after treatment (Z = -1.000, P > 0.05). (2) After treatment, the scores of psychological function, social

  4. Comparison of adaptive radiotherapy techniques for external radiation therapy of canine bladder cancer.

    PubMed

    Nieset, Jessica R; Harmon, Joseph F; Johnson, Thomas E; Larue, Susan M

    2014-01-01

    Daily bladder variations make it difficult to utilize standard radiotherapy as a primary treatment option for muscle-invasive bladder cancer. Our purpose was to develop a model comparing dose distributions of image-guided and adaptive radiotherapy (ART) techniques for canine bladder cancer. Images were obtained retrospectively from cone-beam computed tomography (CBCT) scans used for daily positioning of four dogs undergoing fractionated image-guided radiotherapy (IGRT). Four different treatment plans were modeled for each dog, and dosimetric data were compared. Two plans were developed using planning target volumes based on planning computed tomography (CT) bladder volume. These plans then used bony anatomy or soft tissue anatomy for daily positioning and dosimetric modeling. The third plan type was a hybrid IGRT and ART technique utilizing a library of premade anisotropic planning target volumes using bladder wall motion data and selection of a "plan-of-the-day" determined from positioning CBCT bladder volumes. The fourth plan was an ART technique that constructed a new planning target volume each day based on daily bladder volume as determined by pretreatment CBCT. Dose volume histograms were generated for each plan type and dose distribution for the bladder and rectum were compared between plan types. Irradiated rectal volume decreased and irradiated bladder volume increased as plan conformality increased. ART provided the greatest rectal sparing, with lowest irradiated rectal volume (P < 0.001), and largest bladder volume receiving 95% of the prescription dose (P < 0.001). In our model, adaptive radiotherapy techniques for canine bladder cancer showed significant reduction in rectal volume irradiated when compared to nonadaptive techniques, while maintaining appropriate bladder coverage.

  5. Simulation of macromolecular liquids with the adaptive resolution molecular dynamics technique

    NASA Astrophysics Data System (ADS)

    Peters, J. H.; Klein, R.; Delle Site, L.

    2016-08-01

    We extend the application of the adaptive resolution technique (AdResS) to liquid systems composed of alkane chains of different lengths. The aim of the study is to develop and test the modifications of AdResS required in order to handle the change of representation of large molecules. The robustness of the approach is shown by calculating several relevant structural properties and comparing them with the results of full atomistic simulations. The extended scheme represents a robust prototype for the simulation of macromolecular systems of interest in several fields, from material science to biophysics.

  6. A versatile setup using femtosecond adaptive spectroscopic techniques for coherent anti-Stokes Raman scattering

    SciTech Connect

    Shen, Yujie; Voronine, Dmitri V.; Sokolov, Alexei V.; Scully, Marlan O.

    2015-08-15

    We report a versatile setup based on the femtosecond adaptive spectroscopic techniques for coherent anti-Stokes Raman scattering. The setup uses a femtosecond Ti:Sapphire oscillator source and a folded 4f pulse shaper, in which the pulse shaping is carried out through conventional optical elements and does not require a spatial light modulator. Our setup is simple in alignment, and can be easily switched between the collinear single-beam and the noncollinear two-beam configurations. We demonstrate the capability for investigating both transparent and highly scattering samples by detecting transmitted and reflected signals, respectively.

  7. A versatile setup using femtosecond adaptive spectroscopic techniques for coherent anti-Stokes Raman scattering.

    PubMed

    Shen, Yujie; Voronine, Dmitri V; Sokolov, Alexei V; Scully, Marlan O

    2015-08-01

    We report a versatile setup based on the femtosecond adaptive spectroscopic techniques for coherent anti-Stokes Raman scattering. The setup uses a femtosecond Ti:Sapphire oscillator source and a folded 4f pulse shaper, in which the pulse shaping is carried out through conventional optical elements and does not require a spatial light modulator. Our setup is simple in alignment, and can be easily switched between the collinear single-beam and the noncollinear two-beam configurations. We demonstrate the capability for investigating both transparent and highly scattering samples by detecting transmitted and reflected signals, respectively.

  8. Adaptive Radiation in Socially Advanced Stem-Group Ants from the Cretaceous.

    PubMed

    Barden, Phillip; Grimaldi, David A

    2016-02-22

    Across terrestrial ecosystems, modern ants are ubiquitous. As many as 94 out of every 100 individual arthropods in rainforests are ants, and they constitute up to 15% of animal biomass in the Amazon. Moreover, ants are pervasive agents of natural selection as over 10,000 arthropod species are specialized inquilines or myrmecomorphs living among ants or defending themselves through mimicry. Such impact is traditionally explained by sociality: ants are the first major group of ground-dwelling predatory insects to become eusocial, increasing efficiency of tasks and establishing competitive superiority over solitary species. A wealth of specimens from rich deposits of 99 million-year-old Burmese amber resolves ambiguity regarding sociality and diversity in the earliest ants. The stem-group genus Gerontoformica maintained distinct reproductive castes including morphotypes unknown in solitary aculeate (stinging) wasps, providing insight into early behavior. We present rare aggregations of workers, indicating group recruitment as well as an instance of interspecific combat; such aggression is a social feature of modern ants. Two species and an unusual new genus are described, further expanding the remarkable diversity of early ants. Stem-group ants are recovered as a paraphyletic assemblage at the base of modern lineages varying greatly in size, form, and mouthpart structure, interpreted here as an adaptive radiation. Though Cretaceous stem-group ants were eusocial and adaptively diverse, we hypothesize that their extinction resulted from the rise of competitively superior crown-group taxa that today form massive colonies, consistent with Wilson and Hölldobler's concept of "dynastic succession."

  9. Adaptively Reevaluated Bayesian Localization (ARBL): A novel technique for radiological source localization

    NASA Astrophysics Data System (ADS)

    Miller, Erin A.; Robinson, Sean M.; Anderson, Kevin K.; McCall, Jonathon D.; Prinke, Amanda M.; Webster, Jennifer B.; Seifert, Carolyn E.

    2015-06-01

    We present a novel technique for the localization of radiological sources in urban or rural environments from an aerial platform. The technique is based on a Bayesian approach to localization, in which measured count rates in a time series are compared with predicted count rates from a series of pre-calculated test sources to define likelihood. This technique is expanded by using a localized treatment with a limited field of view (FOV), coupled with a likelihood ratio reevaluation, allowing for real-time computation on commodity hardware for arbitrarily complex detector models and terrain. In particular, detectors with inherent asymmetry of response (such as those employing internal collimation or self-shielding for enhanced directional awareness) are leveraged by this approach to provide improved localization. Results from the localization technique are shown for simulated flight data using monolithic as well as directionally-aware detector models, and the capability of the methodology to locate radioisotopes is estimated for several test cases. This localization technique is shown to facilitate urban search by allowing quick and adaptive estimates of source location, in many cases from a single flyover near a source. In particular, this method represents a significant advancement from earlier methods like full-field Bayesian likelihood, which is not generally fast enough to allow for broad-field search in real time, and highest-net-counts estimation, which has a localization error that depends strongly on flight path and cannot generally operate without exhaustive search.

  10. Adaptively Reevaluated Bayesian Localization (ARBL). A Novel Technique for Radiological Source Localization

    SciTech Connect

    Miller, Erin A.; Robinson, Sean M.; Anderson, Kevin K.; McCall, Jonathon D.; Prinke, Amanda M.; Webster, Jennifer B.; Seifert, Carolyn E.

    2015-01-19

    Here we present a novel technique for the localization of radiological sources in urban or rural environments from an aerial platform. The technique is based on a Bayesian approach to localization, in which measured count rates in a time series are compared with predicted count rates from a series of pre-calculated test sources to define likelihood. Furthermore, this technique is expanded by using a localized treatment with a limited field of view (FOV), coupled with a likelihood ratio reevaluation, allowing for real-time computation on commodity hardware for arbitrarily complex detector models and terrain. In particular, detectors with inherent asymmetry of response (such as those employing internal collimation or self-shielding for enhanced directional awareness) are leveraged by this approach to provide improved localization. Our results from the localization technique are shown for simulated flight data using monolithic as well as directionally-aware detector models, and the capability of the methodology to locate radioisotopes is estimated for several test cases. This localization technique is shown to facilitate urban search by allowing quick and adaptive estimates of source location, in many cases from a single flyover near a source. In particular, this method represents a significant advancement from earlier methods like full-field Bayesian likelihood, which is not generally fast enough to allow for broad-field search in real time, and highest-net-counts estimation, which has a localization error that depends strongly on flight path and cannot generally operate without exhaustive search

  11. Optimal adaptive group sequential design with flexible timing of sample size determination.

    PubMed

    Cui, Lu; Zhang, Lanju; Yang, Bo

    2017-04-26

    Flexible sample size designs, including group sequential and sample size re-estimation designs, have been used as alternatives to fixed sample size designs to achieve more robust statistical power and better trial efficiency. In this work, a new representation of sample size re-estimation design suggested by Cui et al. [5,6] is introduced as an adaptive group sequential design with flexible timing of sample size determination. This generalized adaptive group sequential design allows one time sample size determination either before the start of or in the mid-course of a clinical study. The new approach leads to possible design optimization on an expanded space of design parameters. Its equivalence to sample size re-estimation design proposed by Cui et al. provides further insight on re-estimation design and helps to address common confusions and misunderstanding. Issues in designing flexible sample size trial, including design objective, performance evaluation and implementation are touched upon with an example to illustrate. Copyright © 2017. Published by Elsevier Inc.

  12. The effects of training group exercise class instructors to adopt a motivationally adaptive communication style.

    PubMed

    Ntoumanis, N; Thøgersen-Ntoumani, C; Quested, E; Hancox, J

    2016-06-10

    Drawing from self-determination theory (Deci & Ryan, 2002), we developed and tested an intervention to train fitness instructors to adopt a motivationally adaptive communication style when interacting with exercisers. This was a parallel group, two-arm quasi-experimental design. Participants in the intervention arm were 29 indoor cycling instructors (n = 10 for the control arm) and 246 class members (n = 75 for the control arm). The intervention consisted of face-to-face workshops, education/information video clips, group discussions and activities, brainstorming, individual planning, and practical tasks in the cycling studio. Instructors and exercisers responded to validated questionnaires about instructors' use of motivational strategies and other motivation-related variables before the first workshop and at the end of the third and final workshop (4 months later). Time × arm interactions revealed no significant effects, possibly due to the large attrition of instructors and exercisers in the control arm. Within-group analyses in the intervention arm showed that exercisers' perceptions of instructor motivationally adaptive strategies, psychological need satisfaction, and intentions to remain in the class increased over time. Similarly, instructors in the intervention arm reported being less controlling and experiencing more need satisfaction over time. These results offer initial promising evidence for the positive impact of the training.

  13. Cooperative Learning Groups and the Evolution of Human Adaptability : (Another Reason) Why Hermits Are Rare in Tonga and Elsewhere.

    PubMed

    Bell, Adrian Viliami; Hernandez, Daniel

    2017-03-01

    Understanding the prevalence of adaptive culture in part requires understanding the dynamics of learning. Here we explore the adaptive value of social learning in groups and how formal social groups function as effective mediums of information exchange. We discuss the education literature on Cooperative Learning Groups (CLGs), which outlines the potential of group learning for enhancing learning outcomes. Four qualities appear essential for CLGs to enhance learning: (1) extended conversations, (2) regular interactions, (3) gathering of experts, and (4) incentives for sharing knowledge. We analyze these four qualities within the context of a small-scale agricultural society using data we collected in 2010 and 2012. Through an analysis of surveys, interviews, and observations in the Tongan islands, we describe the role CLGs likely plays in facilitating individuals' learning of adaptive information. Our analysis of group affiliation, membership, and topics of conversation suggest that the first three CLG qualities reflect conditions for adaptive learning in groups. We utilize ethnographic anecdotes to suggest the fourth quality is also conducive to adaptive group learning. Using an evolutionary model, we further explore the scope for CLGs outside the Tongan socioecological context. Model analysis shows that environmental volatility and migration rates among human groups mediate the scope for CLGs. We call for wider attention to how group structure facilitates learning in informal settings, which may be key to assessing the contribution of groups to the evolution of complex, adaptive culture.

  14. A Comparison of Experiential and Didactic Group Counseling Techniques with Black Evening Students.

    ERIC Educational Resources Information Center

    Danford, Richard; Parker, Woodrow M.

    1984-01-01

    Compared the effectiveness of didactic and experiential group counseling techniques for improving the personal and vocational development of 45 Black freshmen evening students. Results showed no positive changes in any of the treatments. Possible contributing factors are discussed. (JAC)

  15. A Comparison of Experiential and Didactic Group Counseling Techniques with Black Evening Students.

    ERIC Educational Resources Information Center

    Danford, Richard; Parker, Woodrow M.

    1984-01-01

    Compared the effectiveness of didactic and experiential group counseling techniques for improving the personal and vocational development of 45 Black freshmen evening students. Results showed no positive changes in any of the treatments. Possible contributing factors are discussed. (JAC)

  16. [A measure of team cohesion in sport. Spanish adaptation of Group Environment Questionnaire (GEQ)].

    PubMed

    Iturbide, Luis María; Elosua, Paula; Yanes, Félix

    2010-08-01

    The aim of this work was to adapt the Group Environment Questionnaire (GEQ) to Spanish. Judgmental procedures were used to assess the linguistic and cultural equivalence of the versions. Psychometric procedures were used in the operational phase of the study. The normative sample comprised 924 sportsmen/sportswomen from 75 teams. The GEQ scale showed suitable indexes of internal consistency and a bidimensional structure based on two factors of the cohesion model, the Task component and the Social component. In addition, a positive relation between team-performance and the Task component of team cohesion was observed. Overall, the results supported the Spanish version of the GEQ.

  17. Determination of Judo Endurance Performance Using the Uchi - Komi Technique and an Adapted Lactate Minimum Test

    PubMed Central

    Azevedo, Paulo H.S.M.; Drigo, Alexandre J.; Carvalho, Mauro C.G.A.; Oliveira, João C.; Nunes, João E.D.; Baldissera, Vilmar; Perez, Sérgio E.A.

    2007-01-01

    This study aimed to evaluate the viability to use Uchi-komi (UK) in the evaluation of the judo endurance performance and using lactate threshold the analysis of the blood lactate ([Lac]) and heart rate (HR) determined through a lactate minimum test. The subjects were a group of 6 male, volunteer judokas, from 25.17 ± 5.76 years old, weight 84.50 ± 23.78 kg and height 1.78 ± 0.10 m, competitors of different levels of performance (from regional to international competitions) and match experience of (11 ± 6) years old. Three tests were performed: a) 3000 m dash in track, b) the adapted test of lactate minimum for running and c) for UK, with execution of the blow ippon-seoi-nague. No significant difference was evident for the track tests and UK in relation to blood lactate and heart rate (p > 0.05) (3.87 ± 0.38 vs 4.17 ± 0.54 mmol·L-1 and 167 ± 2 vs 152 ± 7 b·min-1, respectively). In conclusion it is stressed that: 1) The specific test for lactate minimum in judo sport is a promising possibility of aerobic capacity evaluation and a instrument of intensity training control; 2) The metabolic profile in Vlm and UKlm is similar, because there are not differences in the [Lac] and in the HR at this intensity; 3) It is possible to estimate the training intensity through the determination of the lactate minimum intensity in running (Vlm) and the Heart Rate associated (HR) from the execution of ippon-seoi- nague (uchi-komi) in judo training; 4) The Vlm for judo athletes is approximately 88% of the V3000. Key points The specific test for lactate minimum in judo sport is a promising possibility of aerobic capacity evaluation; This is a instrument for intensity training control for judo players; The metabolic profile is similar between running and uki-komi (ippon-seoi-nague techniques) at lactate minimum intensity. PMID:24198697

  18. Linear dichroism amplification: Adapting a long-known technique for ultrasensitive femtosecond IR spectroscopy

    SciTech Connect

    Rehault, Julien; Helbing, Jan; Zanirato, Vinicio; Olivucci, Massimo

    2011-03-28

    We demonstrate strong amplification of polarization-sensitive transient IR signals using a pseudo-null crossed polarizer technique first proposed by Keston and Lospalluto [Fed. Proc. 10, 207 (1951)] and applied for nanosecond flash photolysis in the visible by Che et al. [Chem. Phys. Lett. 224, 145 (1994)]. We adapted the technique to ultrafast pulsed laser spectroscopy in the infrared using photoelastic modulators, which allow us to measure amplified linear dichroism at kilohertz repetition rates. The method was applied to a photoswitch of the N-alkylated Schiff base family in order to demonstrate its potential of strongly enhancing sensitivity and signal to noise in ultrafast transient IR experiments, to simplify spectra and to determine intramolecular transition dipole orientations.

  19. Infrared image gray adaptive adjusting enhancement algorithm based on gray redundancy histogram-dealing technique

    NASA Astrophysics Data System (ADS)

    Hao, Zi-long; Liu, Yong; Chen, Ruo-wang

    2016-11-01

    In view of the histogram equalizing algorithm to enhance image in digital image processing, an Infrared Image Gray adaptive adjusting Enhancement Algorithm Based on Gray Redundancy Histogram-dealing Technique is proposed. The algorithm is based on the determination of the entire image gray value, enhanced or lowered the image's overall gray value by increasing appropriate gray points, and then use gray-level redundancy HE method to compress the gray-scale of the image. The algorithm can enhance image detail information. Through MATLAB simulation, this paper compares the algorithm with the histogram equalization method and the algorithm based on gray redundancy histogram-dealing technique , and verifies the effectiveness of the algorithm.

  20. Linear dichroism amplification: adapting a long-known technique for ultrasensitive femtosecond IR spectroscopy.

    PubMed

    Réhault, Julien; Zanirato, Vinicio; Olivucci, Massimo; Helbing, Jan

    2011-03-28

    We demonstrate strong amplification of polarization-sensitive transient IR signals using a pseudo-null crossed polarizer technique first proposed by Keston and Lospalluto [Fed. Proc. 10, 207 (1951)] and applied for nanosecond flash photolysis in the visible by Che et al. [Chem. Phys. Lett. 224, 145 (1994)]. We adapted the technique to ultrafast pulsed laser spectroscopy in the infrared using photoelastic modulators, which allow us to measure amplified linear dichroism at kilohertz repetition rates. The method was applied to a photoswitch of the N-alkylated Schiff base family in order to demonstrate its potential of strongly enhancing sensitivity and signal to noise in ultrafast transient IR experiments, to simplify spectra and to determine intramolecular transition dipole orientations.

  1. An adaptive technique to maximize lossless image data compression of satellite images

    NASA Technical Reports Server (NTRS)

    Stewart, Robert J.; Lure, Y. M. Fleming; Liou, C. S. Joe

    1994-01-01

    Data compression will pay an increasingly important role in the storage and transmission of image data within NASA science programs as the Earth Observing System comes into operation. It is important that the science data be preserved at the fidelity the instrument and the satellite communication systems were designed to produce. Lossless compression must therefore be applied, at least, to archive the processed instrument data. In this paper, we present an analysis of the performance of lossless compression techniques and develop an adaptive approach which applied image remapping, feature-based image segmentation to determine regions of similar entropy and high-order arithmetic coding to obtain significant improvements over the use of conventional compression techniques alone. Image remapping is used to transform the original image into a lower entropy state. Several techniques were tested on satellite images including differential pulse code modulation, bi-linear interpolation, and block-based linear predictive coding. The results of these experiments are discussed and trade-offs between computation requirements and entropy reductions are used to identify the optimum approach for a variety of satellite images. Further entropy reduction can be achieved by segmenting the image based on local entropy properties then applying a coding technique which maximizes compression for the region. Experimental results are presented showing the effect of different coding techniques for regions of different entropy. A rule-base is developed through which the technique giving the best compression is selected. The paper concludes that maximum compression can be achieved cost effectively and at acceptable performance rates with a combination of techniques which are selected based on image contextual information.

  2. State Space Composition Technique for Intelligent Wheel Chair Adapting to Environment.

    NASA Astrophysics Data System (ADS)

    Hamagami, Tomoki; Hirata, Hironori

    This paper describes a state space composition technique for the adaptation to environment in the autonomous behavior of intelligent wheel chair (IWC).In the product like IWC with actual sensors, composing state space is difficult problem since environmental information can not be observed sufficiently from restricted sensor inputs.A lot of states observed from same environment position raise the fail of the learning and adaptation with active learning approach.In order to compensate for the effects of the sensor configuration, that is sensor position, angle and precision, a normalization processing of position detector is introduced.In sensor normalization process, IWC scans present environment via range sensors with executing spot-turn, and prepare scan-patterns of each sensor.Then the normalization process adjusts the phase and dynamic range of each pattern to the reference sensor scan-pattern, analyzing phase differences and scale factors of each pattern against reference pattern.Using phase difference and scale factors, automated state space composition is possible.From the simulation experiment with both artificial and real-worlddraft, the automated state space construction is confirmed as a practical approach for pre-processing for environment learning and adaptation.

  3. Hydrological time series modeling: A comparison between adaptive neuro-fuzzy, neural network and autoregressive techniques

    NASA Astrophysics Data System (ADS)

    Lohani, A. K.; Kumar, Rakesh; Singh, R. D.

    2012-06-01

    SummaryTime series modeling is necessary for the planning and management of reservoirs. More recently, the soft computing techniques have been used in hydrological modeling and forecasting. In this study, the potential of artificial neural networks and neuro-fuzzy system in monthly reservoir inflow forecasting are examined by developing and comparing monthly reservoir inflow prediction models, based on autoregressive (AR), artificial neural networks (ANNs) and adaptive neural-based fuzzy inference system (ANFIS). To take care the effect of monthly periodicity in the flow data, cyclic terms are also included in the ANN and ANFIS models. Working with time series flow data of the Sutlej River at Bhakra Dam, India, several ANN and adaptive neuro-fuzzy models are trained with different input vectors. To evaluate the performance of the selected ANN and adaptive neural fuzzy inference system (ANFIS) models, comparison is made with the autoregressive (AR) models. The ANFIS model trained with the input data vector including previous inflows and cyclic terms of monthly periodicity has shown a significant improvement in the forecast accuracy in comparison with the ANFIS models trained with the input vectors considering only previous inflows. In all cases ANFIS gives more accurate forecast than the AR and ANN models. The proposed ANFIS model coupled with the cyclic terms is shown to provide better representation of the monthly inflow forecasting for planning and operation of reservoir.

  4. Detecting discontinuities in time series of upper air data: Demonstration of an adaptive filter technique

    SciTech Connect

    Zurbenko, I.; Chen, J.; Rao, S.T.

    1997-11-01

    The issue of global climate change due to increased anthropogenic emissions of greenhouse gases in the atmosphere has gained considerable attention and importance. Climate change studies require the interpretation of weather data collected in numerous locations and/or over the span of several decades. Unfortunately, these data contain biases caused by changes in instruments and data acquisition procedures. It is essential that biases are identified and/or removed before these data can be used confidently in the context of climate change research. The purpose of this paper is to illustrate the use of an adaptive moving average filter and compare it with traditional parametric methods. The advantage of the adaptive filter over traditional parametric methods is that it is less effected by seasonal patterns and trends. The filter has been applied to upper air relative humidity and temperature data. Applied to generated data, the filter has a root mean squared error accuracy of about 600 days when locating changes of 0.1 standard deviations and about 20 days for changes of 0.5 standard deviations. In some circumstances, the accuracy of location estimation can be improved through parametric techniques used in conjunction with the adaptive filter.

  5. Recent horizontal transfer, functional adaptation and dissemination of a bacterial group II intron.

    PubMed

    LaRoche-Johnston, Félix; Monat, Caroline; Cousineau, Benoit

    2016-10-20

    Group II introns are catalytically active RNA and mobile retroelements present in certain eukaryotic organelles, bacteria and archaea. These ribozymes self-splice from the pre-mRNA of interrupted genes and reinsert within target DNA sequences by retrohoming and retrotransposition. Evolutionary hypotheses place these retromobile elements at the origin of over half the human genome. Nevertheless, the evolution and dissemination of group II introns was found to be quite difficult to infer. We characterized the functional and evolutionary relationship between the model group II intron from Lactococcus lactis, Ll.LtrB, and Ef.PcfG, a newly discovered intron from a clinical strain of Enterococcus faecalis. Ef.PcfG was found to be homologous to Ll.LtrB and to splice and mobilize in its native environment as well as in L. lactis. Interestingly, Ef.PcfG was shown to splice at the same level as Ll.LtrB but to be significantly less efficient to invade the Ll.LtrB recognition site. We also demonstrated that specific point mutations between the IEPs of both introns correspond to functional adaptations which developed in L. lactis as a response to selective pressure on mobility efficiency independently of splicing. The sequence of all the homologous full-length variants of Ll.LtrB were compared and shown to share a conserved pattern of mutation acquisition. This work shows that Ll.LtrB and Ef.PcfG are homologous and have a common origin resulting from a recent lateral transfer event followed by further adaptation to the new target site and/or host environment. We hypothesize that Ef.PcfG is the ancestor of Ll.LtrB and was initially acquired by L. lactis, most probably by conjugation, via a single event of horizontal transfer. Strong selective pressure on homing site invasion efficiency then led to the emergence of beneficial point mutations in the IEP, enabling the successful establishment and survival of the group II intron in its novel lactococcal environment. The current

  6. New analytical expressions of the Rossiter-McLaughlin effect adapted to different observation techniques

    NASA Astrophysics Data System (ADS)

    Boué, G.; Montalto, M.; Boisse, I.; Oshagh, M.; Santos, N. C.

    2013-02-01

    The Rossiter-McLaughlin (hereafter RM) effect is a key tool for measuring the projected spin-orbit angle between stellar spin axes and orbits of transiting planets. However, the measured radial velocity (RV) anomalies produced by this effect are not intrinsic and depend on both instrumental resolution and data reduction routines. Using inappropriate formulas to model the RM effect introduces biases, at least in the projected velocity Vsini⋆ compared to the spectroscopic value. Currently, only the iodine cell technique has been modeled, which corresponds to observations done by, e.g., the HIRES spectrograph of the Keck telescope. In this paper, we provide a simple expression of the RM effect specially designed to model observations done by the Gaussian fit of a cross-correlation function (CCF) as in the routines performed by the HARPS team. We derived a new analytical formulation of the RV anomaly associated to the iodine cell technique. For both formulas, we modeled the subplanet mean velocity vp and dispersion βp accurately taking the rotational broadening on the subplanet profile into account. We compare our formulas adapted to the CCF technique with simulated data generated with the numerical software SOAP-T and find good agreement up to Vsini⋆ ≲ 20 km s-1. In contrast, the analytical models simulating the two different observation techniques can disagree by about 10σ in Vsini⋆ for large spin-orbit misalignments. It is thus important to apply the adapted model when fitting data. A public code implementing the expressions derived in this paper is available at http://www.astro.up.pt/resources/arome. A copy of the code is also available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/550/A53

  7. Protein Secondary Structure Prediction Using Local Adaptive Techniques in Training Neural Networks

    NASA Astrophysics Data System (ADS)

    Aik, Lim Eng; Zainuddin, Zarita; Joseph, Annie

    2008-01-01

    One of the most significant problems in computer molecular biology today is how to predict a protein's three-dimensional structure from its one-dimensional amino acid sequence or generally call the protein folding problem and difficult to determine the corresponding protein functions. Thus, this paper involves protein secondary structure prediction using neural network in order to solve the protein folding problem. The neural network used for protein secondary structure prediction is multilayer perceptron (MLP) of the feed-forward variety. The training set are taken from the protein data bank which are 120 proteins while 60 testing set is the proteins which were chosen randomly from the protein data bank. Multiple sequence alignment (MSA) is used to get the protein similar sequence and Position Specific Scoring matrix (PSSM) is used for network input. The training process of the neural network involves local adaptive techniques. Local adaptive techniques used in this paper comprises Learning rate by sign changes, SuperSAB, Quickprop and RPROP. From the simulation, the performance for learning rate by Rprop and Quickprop are superior to all other algorithms with respect to the convergence time. However, the best result was obtained using Rprop algorithm.

  8. Experimental evaluation of shape memory alloy actuation technique in adaptive antenna design concepts

    NASA Technical Reports Server (NTRS)

    Kefauver, W. Neill; Carpenter, Bernie F.

    1994-01-01

    Creation of an antenna system that could autonomously adapt contours of reflecting surfaces to compensate for structural loads induced by a variable environment would maximize performance of space-based communication systems. Design of such a system requires the comprehensive development and integration of advanced actuator, sensor, and control technologies. As an initial step in this process, a test has been performed to assess the use of a shape memory alloy as a potential actuation technique. For this test, an existing, offset, cassegrain antenna system was retrofit with a subreflector equipped with shape memory alloy actuators for surface contour control. The impacts that the actuators had on both the subreflector contour and the antenna system patterns were measured. The results of this study indicate the potential for using shape memory alloy actuation techniques to adaptively control antenna performance; both variations in gain and beam steering capabilities were demonstrated. Future development effort is required to evolve this potential into a useful technology for satellite applications.

  9. Experimental evaluation of shape memory alloy actuation technique in adaptive antenna design concepts

    NASA Astrophysics Data System (ADS)

    Kefauver, W. Neill; Carpenter, Bernie F.

    1994-09-01

    Creation of an antenna system that could autonomously adapt contours of reflecting surfaces to compensate for structural loads induced by a variable environment would maximize performance of space-based communication systems. Design of such a system requires the comprehensive development and integration of advanced actuator, sensor, and control technologies. As an initial step in this process, a test has been performed to assess the use of a shape memory alloy as a potential actuation technique. For this test, an existing, offset, cassegrain antenna system was retrofit with a subreflector equipped with shape memory alloy actuators for surface contour control. The impacts that the actuators had on both the subreflector contour and the antenna system patterns were measured. The results of this study indicate the potential for using shape memory alloy actuation techniques to adaptively control antenna performance; both variations in gain and beam steering capabilities were demonstrated. Future development effort is required to evolve this potential into a useful technology for satellite applications.

  10. Adaptive technique for matching the spectral response in skin lesions' images

    NASA Astrophysics Data System (ADS)

    Pavlova, P.; Borisova, E.; Pavlova, E.; Avramov, L.

    2015-03-01

    The suggested technique is a subsequent stage for data obtaining from diffuse reflectance spectra and images of diseased tissue with a final aim of skin cancer diagnostics. Our previous work allows us to extract patterns for some types of skin cancer, as a ratio between spectra, obtained from healthy and diseased tissue in the range of 380 - 780 nm region. The authenticity of the patterns depends on the tested point into the area of lesion, and the resulting diagnose could also be fixed with some probability. In this work, two adaptations are implemented to localize pixels of the image lesion, where the reflectance spectrum corresponds to pattern. First adapts the standard to the personal patient and second - translates the spectrum white point basis to the relative white point of the image. Since the reflectance spectra and the image pixels are regarding to different white points, a correction of the compared colours is needed. The latest is done using a standard method for chromatic adaptation. The technique follows the steps below: -Calculation the colorimetric XYZ parameters for the initial white point, fixed by reflectance spectrum from healthy tissue; -Calculation the XYZ parameters for the distant white point on the base of image of nondiseased tissue; -Transformation the XYZ parameters for the test-spectrum by obtained matrix; -Finding the RGB values of the XYZ parameters for the test-spectrum according sRGB; Finally, the pixels of the lesion's image, corresponding to colour from the test-spectrum and particular diagnostic pattern are marked with a specific colour.

  11. Structural break detection method based on the Adaptive Regression Splines technique

    NASA Astrophysics Data System (ADS)

    Kucharczyk, Daniel; Wyłomańska, Agnieszka; Zimroz, Radosław

    2017-04-01

    For many real data, long term observation consists of different processes that coexist or occur one after the other. Those processes very often exhibit different statistical properties and thus before the further analysis the observed data should be segmented. This problem one can find in different applications and therefore new segmentation techniques have been appeared in the literature during last years. In this paper we propose a new method of time series segmentation, i.e. extraction from the analysed vector of observations homogeneous parts with similar behaviour. This method is based on the absolute deviation about the median of the signal and is an extension of the previously proposed techniques also based on the simple statistics. In this paper we introduce the method of structural break point detection which is based on the Adaptive Regression Splines technique, one of the form of regression analysis. Moreover we propose also the statistical test which allows testing hypothesis of behaviour related to different regimes. First, the methodology we apply to the simulated signals with different distributions in order to show the effectiveness of the new technique. Next, in the application part we analyse the real data set that represents the vibration signal from a heavy duty crusher used in a mineral processing plant.

  12. Adapting group interpersonal psychotherapy for a developing country: experience in rural Uganda

    PubMed Central

    VERDELI, HELEN; CLOUGHERTY, KATHLEEN; BOLTON, PAUL; SPEELMAN, LIESBETH; LINCOLN, NDOGONI; BASS, JUDITH; NEUGEBAUER, RICHARD; WEISSMAN, MYRNA M

    2003-01-01

    The current prevalence of depressive symptoms in Southwest Uganda, an area greatly affected by the HIV epidemic, has been shown to be as high as 21%. Traditional healers have expressed inability to treat these symptoms. The lack of physicians and high cost of medication make the use of antidepressants unfeasible. Therefore, an evidence-based psychotherapy was considered a reasonable treatment option by a team of health researchers familiar with the local culture, who designed a randomized controlled clinical trial. Interpersonal psychotherapy in a group format (IPT-G) was selected because it was time limited, was described in a manual, and had evidence of efficacy from clinical trials. Moreover, its focus on interpersonal triggers of depression was considered compatible with the culture. This paper describes the process of adapting the psychotherapy manual and the training of the group leaders who undertook the first psychotherapy clinical trial in Africa. PMID:16946913

  13. Modified H-statistic with adaptive Winsorized mean in two groups test

    NASA Astrophysics Data System (ADS)

    Teh, Kian Wooi; Abdullah, Suhaida; Yahaya, Sharipah Soaad Syed; Yusof, Zahayu Md

    2014-06-01

    t-test is a commonly used test statistics when comparing two independent groups. The computation of this test is simple yet it is powerful under normal distribution and equal variance dataset. However, in real life data, sometimes it is hard to get dataset which has this package. The violation of assumptions (normality and equal variances) will give the devastating effect on the Type I error rate control to the t-test. On the same time, the statistical power also will be reduced. Therefore in this study, the adaptive Winsorised mean with hinge estimator in H-statistic (AWM-H) is proposed. The H-statistic is one of the robust statistics that able to handle the problem of nonnormality in comparing independent group. This procedure originally used Modified One-step M (MOM) estimator which employed trimming process. In the AWM-H procedure, the MOM estimator is replaced with the adaptive Winsorized mean (AWM) as the central tendency measure of the test. The Winsorization process is based on hinge estimator HQ or HQ1. Overall results showed that the proposed method performed better than the original method and the classical method especially under heavy tailed distribution.

  14. Unique Features of Fish Immune Repertoires: Particularities of Adaptive Immunity Within the Largest Group of Vertebrates.

    PubMed

    Magadan, Susana; Sunyer, Oriol J; Boudinot, Pierre

    2015-01-01

    Fishes (i.e., teleost fishes) are the largest group of vertebrates. Although their immune system is based on the fundamental receptors, pathways, and cell types found in all groups of vertebrates, fishes show a diversity of particular features that challenge some classical concepts of immunology. In this chapter, we discuss the particularities of fish immune repertoires from a comparative perspective. We examine how allelic exclusion can be achieved when multiple Ig loci are present, how isotypic diversity and functional specificity impact clonal complexity, how loss of the MHC class II molecules affects the cooperation between T and B cells, and how deep sequencing technologies bring new insights about somatic hypermutation in the absence of germinal centers. The unique coexistence of two distinct B-cell lineages respectively specialized in systemic and mucosal responses is also discussed. Finally, we try to show that the diverse adaptations of immune repertoires in teleosts can help in understanding how somatic adaptive mechanisms of immunity evolved in parallel in different lineages across vertebrates.

  15. Unique Features of Fish Immune Repertoires: Particularities of Adaptive Immunity Within the Largest Group of Vertebrates

    PubMed Central

    Sunyer, Oriol J.

    2016-01-01

    Fishes (i.e., teleost fishes) are the largest group of vertebrates. Although their immune system is based on the fundamental receptors, pathways, and cell types found in all groups of vertebrates, fishes show a diversity of particular features that challenge some classical concepts of immunology. In this chapter, we discuss the particularities of fish immune repertoires from a comparative perspective. We examine how allelic exclusion can be achieved when multiple Ig loci are present, how isotypic diversity and functional specificity impact clonal complexity, how loss of the MHC class II molecules affects the cooperation between T and B cells, and how deep sequencing technologies bring new insights about somatic hypermutation in the absence of germinal centers. The unique coexistence of two distinct B-cell lineages respectively specialized in systemic and mucosal responses is also discussed. Finally, we try to show that the diverse adaptations of immune repertoires in teleosts can help in understanding how somatic adaptive mechanisms of immunity evolved in parallel in different lineages across vertebrates. PMID:26537384

  16. Group Counseling: Techniques for Teaching Social Skills to Students with Special Needs

    ERIC Educational Resources Information Center

    Stephens, Derk; Jain, Sachin; Kim, Kioh

    2010-01-01

    This paper examines literature that supports the use of group counseling techniques in the school setting to teach social skills to children and adolescents with special needs. From the review of this literature it was found that group counseling is a very effective way of addressing a variety of social skills problems that can be displayed by…

  17. Group Testing as a Pedagogical Technique to Enhance Learning in Difficult Subjects

    ERIC Educational Resources Information Center

    Scafe, Marla G.

    2011-01-01

    The purpose of this study was to evaluate the effectiveness of group testing as a pedagogical technique to enhance learning in a difficult subject such as statistics. Individual test scores were compared to their group test scores for the same, identical test. A t test was used to compare the scores for 157 randomly selected MBA students enrolled…

  18. Employing Cognitive Chunking Techniques to Enhance Sight-Reading Performance of Undergraduate Group-Piano Students

    ERIC Educational Resources Information Center

    Pike, Pamela D.; Carter, Rebecca

    2010-01-01

    The purpose of this study was to compare the effect of cognitive chunking techniques among first-semester group-piano music majors. The ability to group discrete pieces of information into larger, more meaningful chunks is essential for efficient cognitive processing. Since reading keyboard music and playing the piano is a cognitively complex…

  19. The Nominal Group Technique as an Evaluation Tool for Solution-Focused Coaching

    ERIC Educational Resources Information Center

    Roeden, John M.; Maaskant, Marian A.; Curfs, Leopold M. G.

    2012-01-01

    Background: Solution-focused coaching (SFC) helps individuals or groups to achieve their preferred outcomes by evoking and co-constructing solutions. SFC has been shown to be helpful for persons with ID as well as for teams coaching people with ID. Nominal Group Technique (NGT) helps to organize people's thoughts with regard to a single question.…

  20. Employing Cognitive Chunking Techniques to Enhance Sight-Reading Performance of Undergraduate Group-Piano Students

    ERIC Educational Resources Information Center

    Pike, Pamela D.; Carter, Rebecca

    2010-01-01

    The purpose of this study was to compare the effect of cognitive chunking techniques among first-semester group-piano music majors. The ability to group discrete pieces of information into larger, more meaningful chunks is essential for efficient cognitive processing. Since reading keyboard music and playing the piano is a cognitively complex…

  1. Adaptive narrow-band interference rejection in a DS spread-spectrum intercept receiver using transform domain signal processing techniques

    NASA Technical Reports Server (NTRS)

    Gevargiz, John; Das, Pankaj K.; Milstein, Laurence B.

    1989-01-01

    An intercept receiver which uses a transform-domain-processing filter is described. This receiver detects direct-sequence BPSK spread-spectrum signals in the presence of narrowband interference by employing adaptive narrowband interference rejection techniques. The improvement in the system performance over that of conventional detection techniques is shown by presenting the results of experimental measurements of probability of detection versus false alarm for an enhanced total power detector. Also presented are certain results corresponding to detection of the spectral lines generated at twice the carrier frequency, wherein the goal is often not just signal detection, but also carrier frequency estimation. The receiver uses one of two transform-domain-processing techniques for adaptive narrowband interference rejection. In the first technique, the narrowband interference is detected and excised in the transform domain by using an adaptive notch filter. In the second technique, the interference is suppressed using soft-limiting in the transform domain.

  2. Approaches to Adaptive Active Acoustic Noise Control at a Point Using Feedforward Techniques.

    NASA Astrophysics Data System (ADS)

    Zulch, Peter A.

    Active acoustic noise control systems have been of interest since their birth in the 1930's. The principle is to superimpose on an unwanted noise wave shape its inverse with the intention of destructive interference. This work presents two approaches to this idea. The first approach uses a direct design method to develop a controller using an auto-regressive moving-average (ARMA) model that will be used to condition the primary noise to produce the required anti-noise for cancellation. The development of this approach has shown that the stability of the controller relies heavily on a non-minimum phase model of the secondary noise path. For this reason, a second approach, using a controller consisting of two parts was developed. The first part of the controller is designed to cancel broadband noise and the second part is an adaptive controller designed to cancel periodic noise. A simple technique for identifying the parameters of the broadband controller is developed. An ARMA model is used, and it is shown that its stability is improved by prefiltering the test signal with a minimum-phase inverse of the secondary noise channel. The periodic controller uses an estimate of the fundamental frequency to cancel the first few harmonics of periodic noise. A computationally efficient adaptive technique based on least squares is developed for updating the harmonic controller gains at each time step. Experimental results are included for the broadband controller, the harmonic controller, and the combination of the two algorithms. The advantages of using both techniques in conjunction are shown using test cases involving both broadband noise and periodic noise.

  3. Enhanced cognitive behavioral therapy for eating disorders adapted for a group setting.

    PubMed

    Wade, Stephanie; Byrne, Sue; Allen, Karina

    2017-08-01

    This randomized control trial is an evaluation of the effectiveness of enhanced cognitive behavioral treatment (CBT-E) for eating disorders adapted for a group setting. The study aimed to examine the effects of group CBT-E on eating disorder psychopathology and additional maintaining pathology. A transdiagnostic sample of individuals with eating disorders with a BMI ≥ 18 kg/m(2) (N = 40) were randomized to an immediate-start or delayed-start condition so as to compare therapeutic effects of group CBT-E with a waitlist control. Global Eating Disorder Examination Questionnaire (EDE-Q) scores, BMI, and measures of Clinical Perfectionism, Self-Esteem, Interpersonal Difficulties, and Mood Intolerance were measured across the 8-week control period, throughout the group treatment and at 3-months post-treatment. Over 70% of those who entered the trial completed treatment. The first eight weeks of group CBT-E were more effective at reducing Global EDE-Q scores than no treatment (waitlist control). By post-treatment, good outcome (a Global EDE-Q within 1 SD of Australian community norms plus BMI ≥ 18.5) was achieved by 67.9% of treatment completers and 66.7% of the total sample. Symptom abstinence within the previous month was reported by 14.3% of treatment completers and 10.3% of the total sample. Significant reductions in Clinical Perfectionism, Self-Esteem, Interpersonal Difficulties, and Mood Intolerance were also observed. This study demonstrated that a group version of CBT-E can be effective at reducing eating disorder psychopathology in a transdiagnostic sample of individuals with eating disorders. Group CBT-E could provide a means of increasing availability of evidence-based treatment for eating disorders. © 2017 Wiley Periodicals, Inc.

  4. EPA Water Resources Adaptation Program (WRAP) Research and Development Activities Methods and Techniques

    EPA Science Inventory

    Adaptation to environmental change is not a new concept. Humans have shown throughout history a capacity for adapting to different climates and environmental changes. Farmers, foresters, civil engineers, have all been forced to adapt to numerous challenges to overcome adversity...

  5. A new CT reconstruction technique using adaptive deformation recovery and intensity correction (ADRIC).

    PubMed

    Zhang, You; Ma, Jianhua; Iyengar, Puneeth; Zhong, Yuncheng; Wang, Jing

    2017-06-01

    Sequential same-patient CT images may involve deformation-induced and non-deformation-induced voxel intensity changes. An adaptive deformation recovery and intensity correction (ADRIC) technique was developed to improve the CT reconstruction accuracy, and to separate deformation from non-deformation-induced voxel intensity changes between sequential CT images. ADRIC views the new CT volume as a deformation of a prior high-quality CT volume, but with additional non-deformation-induced voxel intensity changes. ADRIC first applies the 2D-3D deformation technique to recover the deformation field between the prior CT volume and the new, to-be-reconstructed CT volume. Using the deformation-recovered new CT volume, ADRIC further corrects the non-deformation-induced voxel intensity changes with an updated algebraic reconstruction technique ("ART-dTV"). The resulting intensity-corrected new CT volume is subsequently fed back into the 2D-3D deformation process to further correct the residual deformation errors, which forms an iterative loop. By ADRIC, the deformation field and the non-deformation voxel intensity corrections are optimized separately and alternately to reconstruct the final CT. CT myocardial perfusion imaging scenarios were employed to evaluate the efficacy of ADRIC, using both simulated data of the extended-cardiac-torso (XCAT) digital phantom and experimentally acquired porcine data. The reconstruction accuracy of the ADRIC technique was compared to the technique using ART-dTV alone, and to the technique using 2D-3D deformation alone. The relative error metric and the universal quality index metric are calculated between the images for quantitative analysis. The relative error is defined as the square root of the sum of squared voxel intensity differences between the reconstructed volume and the "ground-truth" volume, normalized by the square root of the sum of squared "ground-truth" voxel intensities. In addition to the XCAT and porcine studies, a physical

  6. Symmetry adaptation of spherical tensor quantities in cubic point groups: comments on a paper by M. Rey et al.

    NASA Astrophysics Data System (ADS)

    Michelot, F.

    2004-04-01

    We underline some inconsistencies in the work [J. Mol. Spectrosc. 219 (2003) 313] concerning symmetry adaptation in cubic groups. Also we show that some rather complicated methods presented can be easily avoided.

  7. Adaptive Phase Synchronization Techniques for Unbalanced and Distorted Three-Phase Voltage System

    NASA Astrophysics Data System (ADS)

    Woinowsky-Krieger, Alexis

    Interfacing and operating AC power electronic systems requires rapid and accurate estimation of the phase angle of the power source, and specifically of the positive sequence of the three-phase utility grid voltage. This is needed to ensure reliable operation of the power control devices and of the resulting power flow. However, the quality of this information is undermined by various distortions and unbalanced conditions of the three-phase grid voltage. Phase estimation and power control can both be performed in real time by a DSP, but a DSP typically has limited computational resources, especially in regards to speed and memory, which motivates the search for computationally efficient algorithms to accomplish these tasks. In contrast to conventional PLL techniques, recent approaches have used adaptive amplitude estimation to enhance the acquisition of the phase information, resulting in faster response and improved performance. This thesis presents a novel technique to estimate the phase of the positive sequence of a three-phase voltage in the presence of frequency variations and unbalanced conditions, referred to as hybrid negative sequence adaptive synchronous amplitude estimation with PLL, or H-NSASAE-PLL. The key feature consists of a feedback structure which embeds a positive sequence PLL and an adaptive synchronous negative sequence estimator to enhance the performance of the PLL. The resulting benefits include faster estimation of the phase of the positive sequence under unbalanced conditions with zero steady state error, simplified tuning of PLL parameters to address a wide range of application requirements, robust performance with respect to distortions and PLL parameters, a structure of minimal dynamical order (fifth) to estimate the main signal parameters of interest, simplified discretization, and reduced computational costs, making the proposed technique suitable for real time execution on a DSP. The H-NSASAE-PLL is developed in the Matlab

  8. The Use of Nominal Group Technique to Determine Additional Support Needs for a Group of Victorian TAFE Managers and Senior Educators

    ERIC Educational Resources Information Center

    Bailey, Anthony

    2013-01-01

    The nominal group technique (NGT) is a structured process to gather information from a group. The technique was first described in 1975 and has since become a widely-used standard to facilitate working groups. The NGT is effective for generating large numbers of creative new ideas and for group priority setting. This paper describes the process of…

  9. A Background Noise Reduction Technique Using Adaptive Noise Cancellation for Microphone Arrays

    NASA Technical Reports Server (NTRS)

    Spalt, Taylor B.; Fuller, Christopher R.; Brooks, Thomas F.; Humphreys, William M., Jr.; Brooks, Thomas F.

    2011-01-01

    Background noise in wind tunnel environments poses a challenge to acoustic measurements due to possible low or negative Signal to Noise Ratios (SNRs) present in the testing environment. This paper overviews the application of time domain Adaptive Noise Cancellation (ANC) to microphone array signals with an intended application of background noise reduction in wind tunnels. An experiment was conducted to simulate background noise from a wind tunnel circuit measured by an out-of-flow microphone array in the tunnel test section. A reference microphone was used to acquire a background noise signal which interfered with the desired primary noise source signal at the array. The technique s efficacy was investigated using frequency spectra from the array microphones, array beamforming of the point source region, and subsequent deconvolution using the Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) algorithm. Comparisons were made with the conventional techniques for improving SNR of spectral and Cross-Spectral Matrix subtraction. The method was seen to recover the primary signal level in SNRs as low as -29 dB and outperform the conventional methods. A second processing approach using the center array microphone as the noise reference was investigated for more general applicability of the ANC technique. It outperformed the conventional methods at the -29 dB SNR but yielded less accurate results when coherence over the array dropped. This approach could possibly improve conventional testing methodology but must be investigated further under more realistic testing conditions.

  10. Manipulating epileptiform bursting in the rat hippocampus using chaos control and adaptive techniques.

    PubMed

    Slutzky, Marc W; Cvitanovic, Predrag; Mogul, David J

    2003-05-01

    Epilepsy is a relatively common disease, afflicting 1%-2% of the population, yet many epileptic patients are not sufficiently helped by current pharmacological therapies. Recent reports have suggested that chaos control techniques may be useful for electrically manipulating epileptiform bursting behavior in vitro and could possibly lead to an alternative method for preventing seizures. We implemented chaos control of spontaneous bursting in the rat hippocampal slice using robust control techniques: stable manifold placement (SMP) and an adaptive tracking (AT) algorithm designed to overcome nonstationarity. We examined the effect of several factors, including control radius size and synaptic plasticity, on control efficacy. AT improved control efficacy over basic SMP control, but relatively frequent stimulation was still necessary and very tight control was only achieved for brief stretches. A novel technique was developed for validating period-1 orbit detection in noisy systems by forcing the system directly onto the period-1 orbit. This forcing analysis suggested that period-1 orbits were indeed present but that control would be difficult because of high noise levels and nonstationarity. Noise might actually be lower in vivo, where regulatory inputs to the hippocampus are still intact. Thus, it may still be feasible to use chaos control algorithms for preventing epileptic seizures.

  11. Deformable mirror models for open-loop adaptive optics using non-parametric estimation techniques

    NASA Astrophysics Data System (ADS)

    Guzmán, Dani; De Cos Juez, Francisco Javier; Myers, Richard; Sánchez Lasheras, Fernando; Young, Laura K.; Guesalaga, Andrés

    2010-07-01

    Open-loop adaptive optics is a technique in which the turbulent wavefront is measured before it hits the deformable mirror for correction; therefore the correct control of the mirror in open-loop is key in achieving the expected level of correction. In this paper, we present non-parametric estimation techniques to model deformable mirrors working in open-loop. We have results with mirrors characterized by non-linear behavior: a Xinetics electrostrictive mirror and a Boston Micromachines MEMS mirror. The inputs for these models are the wavefront corrections to apply to the mirror and the outputs are the set of voltages to shape the mirror. We have performed experiments on both mirrors, achieving Go-To errors relative to peak-to-peak wavefront excursion in the order of 1 % RMS for the Xinetics mirror and 3 % RMS for the Boston mirror . These techniques are trained with interferometric data from the mirror under control; therefore they do not depend on the physical parameters of the device.

  12. Acceptance and Mindfulness Techniques as Applied to Refugee and Ethnic Minority Populations with PTSD: Examples from "Culturally Adapted CBT"

    ERIC Educational Resources Information Center

    Hinton, Devon E.; Pich, Vuth; Hofmann, Stefan G.; Otto, Michael W.

    2013-01-01

    In this article we illustrate how we utilize acceptance and mindfulness techniques in our treatment (Culturally Adapted CBT, or CA-CBT) for traumatized refugees and ethnic minority populations. We present a Nodal Network Model (NNM) of Affect to explain the treatment's emphasis on body-centered mindfulness techniques and its focus on psychological…

  13. Acceptance and Mindfulness Techniques as Applied to Refugee and Ethnic Minority Populations with PTSD: Examples from "Culturally Adapted CBT"

    ERIC Educational Resources Information Center

    Hinton, Devon E.; Pich, Vuth; Hofmann, Stefan G.; Otto, Michael W.

    2013-01-01

    In this article we illustrate how we utilize acceptance and mindfulness techniques in our treatment (Culturally Adapted CBT, or CA-CBT) for traumatized refugees and ethnic minority populations. We present a Nodal Network Model (NNM) of Affect to explain the treatment's emphasis on body-centered mindfulness techniques and its focus on psychological…

  14. Aperiodic dynamics in a deterministic adaptive network model of attitude formation in social groups

    NASA Astrophysics Data System (ADS)

    Ward, Jonathan A.; Grindrod, Peter

    2014-07-01

    Adaptive network models, in which node states and network topology coevolve, arise naturally in models of social dynamics that incorporate homophily and social influence. Homophily relates the similarity between pairs of nodes' states to their network coupling strength, whilst social influence causes coupled nodes' states to convergence. In this paper we propose a deterministic adaptive network model of attitude formation in social groups that includes these effects, and in which the attitudinal dynamics are represented by an activato-inhibitor process. We illustrate that consensus, corresponding to all nodes adopting the same attitudinal state and being fully connected, may destabilise via Turing instability, giving rise to aperiodic dynamics with sensitive dependence on initial conditions. These aperiodic dynamics correspond to the formation and dissolution of sub-groups that adopt contrasting attitudes. We discuss our findings in the context of cultural polarisation phenomena. Social influence. This reflects the fact that people tend to modify their behaviour and attitudes in response to the opinions of others [22-26]. We model social influence via diffusion: agents adjust their state according to a weighted sum (dictated by the evolving network) of the differences between their state and the states of their neighbours. Homophily. This relates the similarity of individuals' states to their frequency and strength of interaction [27]. Thus in our model, homophily drives the evolution of the weighted ‘social' network. A precise formulation of our model is given in Section 2. Social influence and homophily underpin models of social dynamics [21], which cover a wide range of sociological phenomena, including the diffusion of innovations [28-32], complex contagions [33-36], collective action [37-39], opinion dynamics [19,20,40,10,11,13,15,41,16], the emergence of social norms [42-44], group stability [45], social differentiation [46] and, of particular relevance

  15. Adaptation.

    PubMed

    Broom, Donald M

    2006-01-01

    The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and

  16. Efficacy of group-adapted physical exercises in reducing back pain in women with postmenopausal osteoporosis.

    PubMed

    Paolucci, Teresa; Morone, Giovanni; Iosa, Marco; Grasso, Maria Rosaria; Buzi, Emigen; Zangrando, Federico; Paolucci, Stefano; Saraceni, Vincenzo Maria; Fusco, Augusto

    2014-08-01

    The clinical effects of osteoporosis include pain, fractures, and physical disability, causing a loss of independence and necessitating long-term care. Whereas the effects of exercise therapy in decreasing body mass index and preventing fractures are well established, there is no consensus on back pain and quality of life in women with osteoporosis. The aim of this study was to determine the efficacy of a brief course of rehabilitation, comprising group-adapted physical exercises, with regard to back pain, disability, and quality of life in women with postmenopausal osteoporosis who had no evidence of fractures. The enrolled patients were randomized into two groups: the treatment group underwent ten sessions of rehabilitative exercises, and the control group received an instructional booklet with descriptions and figures of exercises that were to be performed at home. Sixty patients completed the trial and assessments, including a 6-month follow-up. The treatment was effective versus the control group, significantly improving pain (Visual Analogue Scale: p < 0.001 at the end of the treatment and at the follow-up; McGill Pain Questionnaire: p = 0.018 at the follow-up), disability (Oswestry Disability Questionnaire: p < 0.001 at the end and follow-up), and quality of life (Shortened Osteoporosis Quality of Life Questionnaire: p = 0.021 at the end of treatment; p = 0.005 at follow-up). Our results suggest that group rehabilitation reduces back pain and improves functional status and quality of life in women with postmenopausal osteoporosis, maintaining these outcomes for 6 months. The use of physical exercises might strengthen the habit to training.

  17. The Novel Nonlinear Adaptive Doppler Shift Estimation Technique and the Coherent Doppler Lidar System Validation Lidar

    NASA Technical Reports Server (NTRS)

    Beyon, Jeffrey Y.; Koch, Grady J.

    2006-01-01

    The signal processing aspect of a 2-m wavelength coherent Doppler lidar system under development at NASA Langley Research Center in Virginia is investigated in this paper. The lidar system is named VALIDAR (validation lidar) and its signal processing program estimates and displays various wind parameters in real-time as data acquisition occurs. The goal is to improve the quality of the current estimates such as power, Doppler shift, wind speed, and wind direction, especially in low signal-to-noise-ratio (SNR) regime. A novel Nonlinear Adaptive Doppler Shift Estimation Technique (NADSET) is developed on such behalf and its performance is analyzed using the wind data acquired over a long period of time by VALIDAR. The quality of Doppler shift and power estimations by conventional Fourier-transform-based spectrum estimation methods deteriorates rapidly as SNR decreases. NADSET compensates such deterioration in the quality of wind parameter estimates by adaptively utilizing the statistics of Doppler shift estimate in a strong SNR range and identifying sporadic range bins where good Doppler shift estimates are found. The authenticity of NADSET is established by comparing the trend of wind parameters with and without NADSET applied to the long-period lidar return data.

  18. Brain surgery in the bush: adapting techniques and technology to fit the developing world.

    PubMed

    Vargas, Jan; Mayegga, Emanuel; Nuwas, Emmanuel; Ellegala, Dilantha B; Kucia, Elisa J; Nicholas, Joyce

    2013-11-01

    The critical shortage of surgical services in many areas of the world has profound effects on local communities. Approximately 11% of global disease burden can be attributed to causes that are surgically treatable. Efforts have been made to recruit professionals from developed nations to compensate for the lack of such expertise. However, this practice has created a cycle of dependency on foreign-trained physicians and the medical tools they bring. Recognition of this problem calls for adaptation of a novel problem-solving approach. This article describes techniques and technology available in east Africa that have been adapted to allow basic and emergency neurosurgery to be performed in the absence of complex medical infrastructure and equipment. Commonplace items found in the local environment can be used to emulate more sophisticated instruments, and community-specific engineering programs can be developed to provide locally produced appropriate technology that promotes independence from Western sources. The local economy benefits from much-needed stimulation when these tools are created locally, and this allows for readily available replacement and repair. More studies are under way to identify problems and implement interventions that are realistic and appropriate for these populations.

  19. Preliminary survey on site-adaptation techniques for satellite-derived and reanalysis solar radiation datasets

    SciTech Connect

    Polo, J.; Wilbert, S.; Ruiz-Arias, J. A.; Meyer, R.; Gueymard, C.; Súri, M.; Martín, L.; Mieslinger, T.; Blanc, P.; Grant, I.; Boland, J.; Ineichen, P.; Remund, J.; Escobar, R.; Troccoli, A.; Sengupta, M.; Nielsen, K. P.; Renne, D.; Geuder, N.; Cebecauer, T.

    2016-07-01

    At any site, the bankability of a projected solar power plant largely depends on the accuracy and general quality of the solar radiation data generated during the solar resource assessment phase. The term 'site adaptation' has recently started to be used in the framework of solar energy projects to refer to the improvement that can be achieved in satellite-derived solar irradiance and model data when short-term local ground measurements are used to correct systematic errors and bias in the original dataset. This contribution presents a preliminary survey of different possible techniques that can improve long-term satellite-derived and model-derived solar radiation data through the use of short-term on-site ground measurements. The possible approaches that are reported here may be applied in different ways, depending on the origin and characteristics of the uncertainties in the modeled data. This work, which is the first step of a forthcoming in-depth assessment of methodologies for site adaptation, has been done within the framework of the International Energy Agency Solar Heating and Cooling Programme Task 46 'Solar Resource Assessment and Forecasting.'

  20. Dynamic optical aberration correction with adaptive coded apertures techniques in conformal imaging

    NASA Astrophysics Data System (ADS)

    Li, Yan; Hu, Bin; Zhang, Pengbin; Zhang, Binglong

    2015-02-01

    Conformal imaging systems are confronted with dynamic aberration in optical design processing. In classical optical designs, for combination high requirements of field of view, optical speed, environmental adaption and imaging quality, further enhancements can be achieved only by the introduction of increased complexity of aberration corrector. In recent years of computational imaging, the adaptive coded apertures techniques which has several potential advantages over more traditional optical systems is particularly suitable for military infrared imaging systems. The merits of this new concept include low mass, volume and moments of inertia, potentially lower costs, graceful failure modes, steerable fields of regard with no macroscopic moving parts. Example application for conformal imaging system design where the elements of a set of binary coded aperture masks are applied are optimization designed is presented in this paper, simulation results show that the optical performance is closely related to the mask design and the reconstruction algorithm optimization. As a dynamic aberration corrector, a binary-amplitude mask located at the aperture stop is optimized to mitigate dynamic optical aberrations when the field of regard changes and allow sufficient information to be recorded by the detector for the recovery of a sharp image using digital image restoration in conformal optical system.

  1. Nonlinear adaptive control based on fuzzy sliding mode technique and fuzzy-based compensator.

    PubMed

    Nguyen, Sy Dzung; Vo, Hoang Duy; Seo, Tae-Il

    2017-09-01

    It is difficult to efficiently control nonlinear systems in the presence of uncertainty and disturbance (UAD). One of the main reasons derives from the negative impact of the unknown features of UAD as well as the response delay of the control system on the accuracy rate in the real time of the control signal. In order to deal with this, we propose a new controller named CO-FSMC for a class of nonlinear control systems subjected to UAD, which is constituted of a fuzzy sliding mode controller (FSMC) and a fuzzy-based compensator (CO). Firstly, the FSMC and CO are designed independently, and then an adaptive fuzzy structure is discovered to combine them. Solutions for avoiding the singular cases of the fuzzy-based function approximation and reducing the calculating cost are proposed. Based on the solutions, fuzzy sliding mode technique, lumped disturbance observer and Lyapunov stability analysis, a closed-loop adaptive control law is formulated. Simulations along with a real application based on a semi-active train-car suspension are performed to fully evaluate the method. The obtained results reflected that vibration of the chassis mass is insensitive to UAD. Compared with the other fuzzy sliding mode control strategies, the CO-FSMC can provide the best control ability to reduce unwanted vibrations. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Optical Cluster-Finding with an Adaptive Matched-Filter Technique: Algorithm and Comparison with Simulations

    SciTech Connect

    Dong, Feng; Pierpaoli, Elena; Gunn, James E.; Wechsler, Risa H.

    2007-10-29

    We present a modified adaptive matched filter algorithm designed to identify clusters of galaxies in wide-field imaging surveys such as the Sloan Digital Sky Survey. The cluster-finding technique is fully adaptive to imaging surveys with spectroscopic coverage, multicolor photometric redshifts, no redshift information at all, and any combination of these within one survey. It works with high efficiency in multi-band imaging surveys where photometric redshifts can be estimated with well-understood error distributions. Tests of the algorithm on realistic mock SDSS catalogs suggest that the detected sample is {approx} 85% complete and over 90% pure for clusters with masses above 1.0 x 10{sup 14}h{sup -1} M and redshifts up to z = 0.45. The errors of estimated cluster redshifts from maximum likelihood method are shown to be small (typically less that 0.01) over the whole redshift range with photometric redshift errors typical of those found in the Sloan survey. Inside the spherical radius corresponding to a galaxy overdensity of {Delta} = 200, we find the derived cluster richness {Lambda}{sub 200} a roughly linear indicator of its virial mass M{sub 200}, which well recovers the relation between total luminosity and cluster mass of the input simulation.

  3. Two-dimensional radial acquisition technique with density adaption in sodium MRI.

    PubMed

    Konstandin, Simon; Nagel, Armin M; Heiler, Patrick M; Schad, Lothar R

    2011-04-01

    Conventional 2D radial projections suffer from losses in signal-to-noise ratio efficiency because of the nonuniform k-space sampling. In this study, a 2D projection reconstruction method with variable gradient amplitudes is presented to cover the k-space uniformly. The gradient is designed to keep the average sampling density constant. By this, signal-to-noise ratio is increased, and the linear form of the radial trajectory is kept. The simple gradient design and low hardware requirements in respect of slew rate allow an easy implementation at MR scanners. Measurements with the density-adapted 2D radial trajectory were compared with the conventional projection reconstruction method. It is demonstrated that the density-adapted 2D radial trajectory technique provides higher signal-to-noise ratio (up to 28% in brain tissue), less blurring, and fewer artifacts in the presence of magnetic field inhomogeneities than imaging with the conventional 2D radial trajectory scheme. The presented sequence is well-suited for electrocardiographically gated sodium heart MRI and other applications with short relaxation times. Copyright © 2010 Wiley-Liss, Inc.

  4. Automated object extraction from remote sensor image based on adaptive thresholding technique

    NASA Astrophysics Data System (ADS)

    Zhao, Tongzhou; Ma, Shuaijun; Li, Jin; Ming, Hui; Luo, Xiaobo

    2009-10-01

    Detection and extraction of the dim moving small objects in the infrared image sequences is an interesting research area. A system for detection of the dim moving small targets in the IR image sequences is presented, and a new algorithm having high performance for extracting moving small targets in infrared image sequences containing cloud clutter is proposed in the paper. This method can get the better detection precision than some other methods, and two independent units can realize the calculative process. The novelty of the algorithm is that it uses adaptive thresholding technique of the moving small targets in both the spatial domain and temporal domain. The results of experiment show that the algorithm we presented has high ratio of detection precision.

  5. Backstepping-based cooperative and adaptive tracking control design for a group of underactuated AUVs in horizontal plan

    NASA Astrophysics Data System (ADS)

    Ghommam, Jawhar; Saad, Maarouf

    2014-05-01

    In this paper, we investigate new implementable cooperative adaptive backstepping controllers for a group of underactuated autonomous vehicles that are communicating with their local neighbours to track a time-varying virtual leader of which the relative position may only be available to a portion of the team members. At the kinematic cooperative control level of the autonomous underwater vehicle, the virtual cooperative controller is basically designed on a proportional and derivative consensus algorithm presented in Ren (2010), which involves velocity information from local neighbours. In this paper, we propose a new design algorithm based on singular perturbation theory that precludes the use of the neighbours' velocity information in the cooperative design. At the dynamic cooperative control level, calculation of the partial derivatives of some stabilising functions which in turn will contain velocity information from the local neighbours is required. To facilitate the implementation of the cooperative controllers, we propose a command filter approach technique to avoid analytic differentiation of the virtual cooperative control laws. We show how Lyapunov-based techniques and graph theory can be combined together to yield a robust cooperative controller where the uncertain dynamics of the cooperating vehicles and the constraints on the communication topology which contains a directed spanning tree are explicitly taken into account. Simulation results with a dynamic model of underactuated autonomous underwater vehicles moving on the horizontal plane are presented and discussed.

  6. Expression and purification of a cold-adapted group III trypsin in Escherichia coli.

    PubMed

    Pálsdóttir, Helga Margrét; Gudmundsdóttir, Agústa

    2007-02-01

    The recently classified group III trypsins include members like Atlantic cod (Gadus morhua) trypsin Y as well as seven analogues from other cold-adapted fish species. The eight group III trypsins have been characterized from their cDNAs and deduced amino acid sequences but none of the enzymes have been isolated from their native sources. This study describes the successful expression and purification of a recombinant HP-thioredoxin-trypsin Y fusion protein in the His-Patch ThioFusion Escherichia coli expression system and its purification by chromatographic methods. The recombinant form of trypsin Y was previously expressed in Pichia pastoris making it the first biochemically characterized group III trypsin. It has dual substrate specificity towards trypsin and chymotrypsin substrates and demonstrates an increasing activity at temperatures between 2 and 21 degrees C with a complete inactivation at 30 degrees C. The aim of the study was to facilitate further studies of recombinant trypsin Y by finding an expression system yielding higher amounts of the enzyme than possible in our hands in the P. pastoris system. Also, commercial production of trypsin Y will require an efficient and inexpensive expression system like the His-Patch ThioFusion E. coli expression system described here as the enzyme is produced in very low amounts in the Atlantic cod.

  7. The pursuit of balance: An overview of covariate-adaptive randomization techniques in clinical trials.

    PubMed

    Lin, Yunzhi; Zhu, Ming; Su, Zheng

    2015-11-01

    Randomization is fundamental to the design and conduct of clinical trials. Simple randomization ensures independence among subject treatment assignments and prevents potential selection biases, yet it does not guarantee balance in covariate distributions across treatment groups. Ensuring balance in important prognostic covariates across treatment groups is desirable for many reasons. A broad class of randomization methods for achieving balance are reviewed in this paper; these include block randomization, stratified randomization, minimization, and dynamic hierarchical randomization. Practical considerations arising from experience with using the techniques are described. A review of randomization methods used in practice in recent randomized clinical trials is also provided.

  8. Robust breathing signal extraction from cone beam CT projections based on adaptive and global optimization techniques

    NASA Astrophysics Data System (ADS)

    Chao, Ming; Wei, Jie; Li, Tianfang; Yuan, Yading; Rosenzweig, Kenneth E.; Lo, Yeh-Chi

    2016-04-01

    We present a study of extracting respiratory signals from cone beam computed tomography (CBCT) projections within the framework of the Amsterdam Shroud (AS) technique. Acquired prior to the radiotherapy treatment, CBCT projections were preprocessed for contrast enhancement by converting the original intensity images to attenuation images with which the AS image was created. An adaptive robust z-normalization filtering was applied to further augment the weak oscillating structures locally. From the enhanced AS image, the respiratory signal was extracted using a two-step optimization approach to effectively reveal the large-scale regularity of the breathing signals. CBCT projection images from five patients acquired with the Varian Onboard Imager on the Clinac iX System Linear Accelerator (Varian Medical Systems, Palo Alto, CA) were employed to assess the proposed technique. Stable breathing signals can be reliably extracted using the proposed algorithm. Reference waveforms obtained using an air bellows belt (Philips Medical Systems, Cleveland, OH) were exported and compared to those with the AS based signals. The average errors for the enrolled patients between the estimated breath per minute (bpm) and the reference waveform bpm can be as low as  -0.07 with the standard deviation 1.58. The new algorithm outperformed the original AS technique for all patients by 8.5% to 30%. The impact of gantry rotation on the breathing signal was assessed with data acquired with a Quasar phantom (Modus Medical Devices Inc., London, Canada) and found to be minimal on the signal frequency. The new technique developed in this work will provide a practical solution to rendering markerless breathing signal using the CBCT projections for thoracic and abdominal patients.

  9. Adaptive noise suppression technique for dense 3D point cloud reconstructions from monocular vision

    NASA Astrophysics Data System (ADS)

    Diskin, Yakov; Asari, Vijayan K.

    2012-10-01

    Mobile vision-based autonomous vehicles use video frames from multiple angles to construct a 3D model of their environment. In this paper, we present a post-processing adaptive noise suppression technique to enhance the quality of the computed 3D model. Our near real-time reconstruction algorithm uses each pair of frames to compute the disparities of tracked feature points to translate the distance a feature has traveled within the frame in pixels into real world depth values. As a result these tracked feature points are plotted to form a dense and colorful point cloud. Due to the inevitable small vibrations in the camera and the mismatches within the feature tracking algorithm, the point cloud model contains a significant amount of misplaced points appearing as noise. The proposed noise suppression technique utilizes the spatial information of each point to unify points of similar texture and color into objects while simultaneously removing noise dissociated with any nearby objects. The noise filter combines all the points of similar depth into 2D layers throughout the point cloud model. By applying erosion and dilation techniques we are able to eliminate the unwanted floating points while retaining points of larger objects. To reverse the compression process, we transform the 2D layer back into the 3D model allowing points to return to their original position without the attached noise components. We evaluate the resulting noiseless point cloud by utilizing an unmanned ground vehicle to perform obstacle avoidance tasks. The contribution of the noise suppression technique is measured by evaluating the accuracy of the 3D reconstruction.

  10. Robust breathing signal extraction from cone beam CT projections based on adaptive and global optimization techniques

    PubMed Central

    Chao, Ming; Wei, Jie; Li, Tianfang; Yuan, Yading; Rosenzweig, Kenneth E; Lo, Yeh-Chi

    2017-01-01

    We present a study of extracting respiratory signals from cone beam computed tomography (CBCT) projections within the framework of the Amsterdam Shroud (AS) technique. Acquired prior to the radiotherapy treatment, CBCT projections were preprocessed for contrast enhancement by converting the original intensity images to attenuation images with which the AS image was created. An adaptive robust z-normalization filtering was applied to further augment the weak oscillating structures locally. From the enhanced AS image, the respiratory signal was extracted using a two-step optimization approach to effectively reveal the large-scale regularity of the breathing signals. CBCT projection images from five patients acquired with the Varian Onboard Imager on the Clinac iX System Linear Accelerator (Varian Medical Systems, Palo Alto, CA) were employed to assess the proposed technique. Stable breathing signals can be reliably extracted using the proposed algorithm. Reference waveforms obtained using an air bellows belt (Philips Medical Systems, Cleveland, OH) were exported and compared to those with the AS based signals. The average errors for the enrolled patients between the estimated breath per minute (bpm) and the reference waveform bpm can be as low as −0.07 with the standard deviation 1.58. The new algorithm outperformed the original AS technique for all patients by 8.5% to 30%. The impact of gantry rotation on the breathing signal was assessed with data acquired with a Quasar phantom (Modus Medical Devices Inc., London, Canada) and found to be minimal on the signal frequency. The new technique developed in this work will provide a practical solution to rendering markerless breathing signal using the CBCT projections for thoracic and abdominal patients. PMID:27008349

  11. Design of synchronization technique for uncertain discrete network group with diverse structures

    NASA Astrophysics Data System (ADS)

    Lü, Ling; Li, Chengren; Li, Gang; Sun, Ao; Yan, Zhe; Rong, Tingting; Gao, Yan

    2017-01-01

    In this work, we design a novel synchronization technique to realize the synchronization of the network group which is constituted by some uncertain discrete networks with diverse structures. Based on Lyapunov theorem, the selection principle of the control inputs and identification law of uncertain parameters in networks are determined, and the synchronization conditions of network group are obtained. Finally, numerical simulations using one-dimensional convective equations with spatiotemporal chaos behaviors illustrate the performance of the synchronization scheme. The research results show that our synchronization technique can be suitable for the network connecting arbitrarily, and not only the network number but also node number in each network can also be chosen freely.

  12. Nurses' Educational Needs Assessment for Financial Management Education Using the Nominal Group Technique.

    PubMed

    Noh, Wonjung; Lim, Ji Young

    2015-06-01

    The purpose of this study was to identify the financial management educational needs of nurses in order to development an educational program to strengthen their financial management competencies. Data were collected from two focus groups using the nominal group technique. The study consisted of three steps: a literature review, focus group discussion using the nominal group technique, and data synthesis. After analyzing the results, nine key components were selected: corporate management and accounting, introduction to financial management in hospitals, basic structure of accounting, basics of hospital accounting, basics of financial statements, understanding the accounts of financial statements, advanced analysis of financial statements, application of financial management, and capital financing of hospitals. The present findings can be used to develop a financial management education program to strengthen the financial management competencies of nurses. Copyright © 2015. Published by Elsevier B.V.

  13. Calibrating HIMMELI, a New Wetland CH4 Model, with Adaptive MCMC Techniques

    NASA Astrophysics Data System (ADS)

    Susiluoto, J.

    2016-12-01

    Wetland methane modeling in global earth system models is still arelatively difficult task. A new wetland methane emission modelcomponent, HIMMELI (HelsinkI Model of MEthane buiLd-up and emIssionfor peatlands), was developed and calibrated to address thequestion. It contains processes for production of methane from NPP andpeat decomposition, and its transport in the soil via diffusion, planttransport, and ebullition.The model was calibrated with site level methane flux time series withBayesian techniques, utilizing measured input for model forcing. Weused optimization algorithms and adaptive Markov Chain Monte Carlomethods, in both hierarchial and non-hierarchial settings. Weevaluated the error distributions, parameter posterior distributions,and the differences between various flux estimates from the posterior,as well as the feasibility of using the model for predicting thefuture fluxes, drawing conclusions regarding the reliability of such amodel in a climate modeling setting.We found out that the model is quite capable, and that the resultsgiven by the various optimization techniques vary somewhat. We alsofound out that the calibration for the climate model integrationuse-case is challenging. Additionally, from the inverse modelingresults of the parameters, we were able to analyze some features ofthe year-to-year variablility of the wetland's physical state.

  14. Blind switch damping (BSD): A self-adaptive semi-active damping technique

    NASA Astrophysics Data System (ADS)

    Lallart, Mickaël; Harari, Stéphanie; Petit, Lionel; Guyomar, Daniel; Richard, Thibaut; Richard, Claude; Gaudiller, Luc

    2009-11-01

    Much attention was given to the control of vibrations for smart structures equipped with piezoelectric elements in the nineties. Active control has shown its efficiency, however, necessitating important power requirements and complex signal processing. To bypass these drawbacks, semi-passive control schemes have been proposed. In the semi-passive approach, the piezoelectric element is intermittently switched from open circuit to a specific circuit synchronously with the structure motion. Such systems are simpler than active control methods and require low power supply (they can even be self-powered), but necessitate a deterministic approach. In this paper, a novel semi-passive method is proposed for a piezoceramic actuator coupled with a switching resistor/inductor shunt. This method, named BSD (for blind switch damping), has the advantage of being independent from the structure vibrations and does not need any model of the smart structure. This technique also exhibits low requirements in terms of power supply. In the BSD technique, the piezoelectric element can be either switched on a short circuit or the piezovoltage magnitude can artificially be increased by switching on piecewise constant or adaptive voltage sources, making the approach semi-active. Experimental measurements carried out on a simple structure (clamped-free smart beam) show good agreements with theoretical predictions, exhibiting damping performances similar to previously proposed semi-passive and semi-active methods.

  15. Motor unit activity within the depth of the masseter characterized by an adapted scanning EMG technique.

    PubMed

    van Dijk, J P; Eiglsperger, U; Hellmann, D; Giannakopoulos, N N; McGill, K C; Schindler, H J; Lapatki, B G

    2016-09-01

    To study motor unit activity in the medio-lateral extension of the masseter using an adapted scanning EMG technique that allows studying the territories of multiple motor units (MUs) in one scan. We studied the m. masseter of 10 healthy volunteers in whom two scans were performed. A monopolar scanning needle and two pairs of fine-wire electrodes were inserted into the belly of the muscle. The signals of the fine wire electrodes were decomposed into the contribution of single MUs and used as a trigger for the scanning needle. In this manner multiple MU territory scans were obtained simultaneously. We determined 161 MU territories. The maximum number of territories obtained in one scan was 15. The median territory size was 4.0mm. Larger and smaller MU territories were found throughout the muscle. The presented technique showed its feasibility in obtaining multiple MU territories in one scan. MUs were active throughout the depth of the muscle. The distribution of electrical and anatomical size of MUs substantiates the heterogeneous distribution of MUs throughout the muscle volume. This distributed activity may be of functional significance for the stabilization of the muscle during force generation. Copyright © 2016 International Federation of Clinical Neurophysiology. All rights reserved.

  16. How dietary intake methodology is adapted for use in European immigrant population groups - a review.

    PubMed

    Ngo, Joy; Gurinovic, Mirjana; Frost-Andersen, Lene; Serra-Majem, Lluís

    2009-07-01

    Immigrants comprise a noteworthy segment of the European population whose numbers are increasing. Research on the dietary habits of immigrants is critical for correctly providing diet counselling and implementing effective interventions. The aim of the present study was to identify the presently used methods and adaptations required for measuring dietary intake in European immigrant groups. A comprehensive review strategy included a structured MEDLINE search, related references and key expert consultations. The review targeted adults from non-European union (European union-15 countries) ethnic groups having the largest populations in Europe. As studies evaluating nutrient intake were scarce, papers evaluating intake at the level of foods were included. Forty-six papers were selected. Although Eastern Europe, Turkey, Africa (North, Sub-Saharan and Afro-Caribbean), Asia and Latin America represented the most numerous immigrant groups, papers on dietary intake were not available for all populations. Interview-administered FFQ and repeated 24 hour recalls were the most frequently applied instruments. Inclusion of ethnic foods and quantification of specific portion sizes of traditional foods and dishes in assessment tools as well as food composition databases were commonly identified problems. For FFQ, food list elaboration required particular consideration to reflect key ethnic foods and relative contribution to nutrient intake. Extra efforts were observed to overcome cultural barriers to study participation. Evaluating dietary intake of immigrant populations requires special attention to various methodological aspects (sampling, recruiting, instruments used, method of administration, food composition database, acculturation, etc.) so as to adequately address the range of socio-cultural factors inherent in these nutritionally at risk target groups.

  17. ADAPTIVE FINITE ELEMENT MODELING TECHNIQUES FOR THE POISSON-BOLTZMANN EQUATION.

    PubMed

    Holst, Michael; McCammon, James Andrew; Yu, Zeyun; Zhou, Youngcheng; Zhu, Yunrong

    2012-01-01

    We consider the design of an effective and reliable adaptive finite element method (AFEM) for the nonlinear Poisson-Boltzmann equation (PBE). We first examine the two-term regularization technique for the continuous problem recently proposed by Chen, Holst, and Xu based on the removal of the singular electrostatic potential inside biomolecules; this technique made possible the development of the first complete solution and approximation theory for the Poisson-Boltzmann equation, the first provably convergent discretization, and also allowed for the development of a provably convergent AFEM. However, in practical implementation, this two-term regularization exhibits numerical instability. Therefore, we examine a variation of this regularization technique which can be shown to be less susceptible to such instability. We establish a priori estimates and other basic results for the continuous regularized problem, as well as for Galerkin finite element approximations. We show that the new approach produces regularized continuous and discrete problems with the same mathematical advantages of the original regularization. We then design an AFEM scheme for the new regularized problem, and show that the resulting AFEM scheme is accurate and reliable, by proving a contraction result for the error. This result, which is one of the first results of this type for nonlinear elliptic problems, is based on using continuous and discrete a priori L(∞) estimates to establish quasi-orthogonality. To provide a high-quality geometric model as input to the AFEM algorithm, we also describe a class of feature-preserving adaptive mesh generation algorithms designed specifically for constructing meshes of biomolecular structures, based on the intrinsic local structure tensor of the molecular surface. All of the algorithms described in the article are implemented in the Finite Element Toolkit (FETK), developed and maintained at UCSD. The stability advantages of the new regularization scheme

  18. Adaptive Photothermal Emission Analysis Techniques for Robust Thermal Property Measurements of Thermal Barrier Coatings

    NASA Astrophysics Data System (ADS)

    Valdes, Raymond

    The characterization of thermal barrier coating (TBC) systems is increasingly important because they enable gas turbine engines to operate at high temperatures and efficiency. Phase of photothermal emission analysis (PopTea) has been developed to analyze the thermal behavior of the ceramic top-coat of TBCs, as a nondestructive and noncontact method for measuring thermal diffusivity and thermal conductivity. Most TBC allocations are on actively-cooled high temperature turbine blades, which makes it difficult to precisely model heat transfer in the metallic subsystem. This reduces the ability of rote thermal modeling to reflect the actual physical conditions of the system and can lead to higher uncertainty in measured thermal properties. This dissertation investigates fundamental issues underpinning robust thermal property measurements that are adaptive to non-specific, complex, and evolving system characteristics using the PopTea method. A generic and adaptive subsystem PopTea thermal model was developed to account for complex geometry beyond a well-defined coating and substrate system. Without a priori knowledge of the subsystem characteristics, two different measurement techniques were implemented using the subsystem model. In the first technique, the properties of the subsystem were resolved as part of the PopTea parameter estimation algorithm; and, the second technique independently resolved the subsystem properties using a differential "bare" subsystem. The confidence in thermal properties measured using the generic subsystem model is similar to that from a standard PopTea measurement on a "well-defined" TBC system. Non-systematic bias-error on experimental observations in PopTea measurements due to generic thermal model discrepancies was also mitigated using a regression-based sensitivity analysis. The sensitivity analysis reported measurement uncertainty and was developed into a data reduction method to filter out these "erroneous" observations. It was found

  19. ADAPTIVE FINITE ELEMENT MODELING TECHNIQUES FOR THE POISSON-BOLTZMANN EQUATION

    PubMed Central

    HOLST, MICHAEL; MCCAMMON, JAMES ANDREW; YU, ZEYUN; ZHOU, YOUNGCHENG; ZHU, YUNRONG

    2011-01-01

    We consider the design of an effective and reliable adaptive finite element method (AFEM) for the nonlinear Poisson-Boltzmann equation (PBE). We first examine the two-term regularization technique for the continuous problem recently proposed by Chen, Holst, and Xu based on the removal of the singular electrostatic potential inside biomolecules; this technique made possible the development of the first complete solution and approximation theory for the Poisson-Boltzmann equation, the first provably convergent discretization, and also allowed for the development of a provably convergent AFEM. However, in practical implementation, this two-term regularization exhibits numerical instability. Therefore, we examine a variation of this regularization technique which can be shown to be less susceptible to such instability. We establish a priori estimates and other basic results for the continuous regularized problem, as well as for Galerkin finite element approximations. We show that the new approach produces regularized continuous and discrete problems with the same mathematical advantages of the original regularization. We then design an AFEM scheme for the new regularized problem, and show that the resulting AFEM scheme is accurate and reliable, by proving a contraction result for the error. This result, which is one of the first results of this type for nonlinear elliptic problems, is based on using continuous and discrete a priori L∞ estimates to establish quasi-orthogonality. To provide a high-quality geometric model as input to the AFEM algorithm, we also describe a class of feature-preserving adaptive mesh generation algorithms designed specifically for constructing meshes of biomolecular structures, based on the intrinsic local structure tensor of the molecular surface. All of the algorithms described in the article are implemented in the Finite Element Toolkit (FETK), developed and maintained at UCSD. The stability advantages of the new regularization scheme

  20. Synthesis of Perfluorinated Ethers by Solution Phase Direct Fluorination: An Adaptation of the La-Mar Technique

    DTIC Science & Technology

    1990-08-22

    by 3 GORDON BENNETT RUTHERFORD, B.S. SUPERVISING PROFESSOR: RICHARD J. LAGOW The synthesis of several perfluorinated ethers of pentaerythritol ...II i SYNTHESIS OF PERFLUORINATED ETHERS BY SOLUTION PHASE 3 DIRECT FLUORINATION: AN ADAPTATION OF THE LA-MAR TECHNIQUEI g oo/z3 - - G 5 / I P I Al 3...g I L__ iI !V I I SYNTHESIS OF PERFLUORINATED ETHERS BY SOLUTION PHASE 3 DIRECT FLUORINATION: AN ADAPTATION OF THE LA-MAR TECHNIQUE 3 GORDON BENNETT

  1. Group Guidance Services with Self-Regulation Technique to Improve Student Learning Motivation in Junior High School (JHS)

    ERIC Educational Resources Information Center

    Pranoto, Hadi; Atieka, Nurul; Wihardjo, Sihadi Darmo; Wibowo, Agus; Nurlaila, Siti; Sudarmaji

    2016-01-01

    This study aims at: determining students motivation before being given a group guidance with self-regulation technique, determining students' motivation after being given a group counseling with self-regulation technique, generating a model of group counseling with self-regulation technique to improve motivation of learning, determining the…

  2. An Empirical Test of the Nominal Group Technique in State Solar Energy Planning.

    ERIC Educational Resources Information Center

    Stephenson, Blair Y.; And Others

    1982-01-01

    Investigated use of the Nominal Group Technique (NGT) as an informational input mechanism into the formulation of a Solar Energy Plan. Data collected from a questionnaire indicated that the NGT was rated as being a highly effective mechanism providing input into the solar energy planning process. (Author/RC)

  3. Identifying the Professional Development Needs of Early Career Teachers in Scotland Using Nominal Group Technique

    ERIC Educational Resources Information Center

    Kennedy, Aileen; Clinton, Colleen

    2009-01-01

    This paper reports on phase 1 of a project commissioned by Learning and Teaching Scotland to explore the continuing professional development (CPD) needs of teachers in Scotland in years 2-6 of their careers. Nominal group technique (NGT) was employed to identify the CPD needs of year 2-6 teachers and to identify the relative priority of these…

  4. Investigating the Effects of Group Practice Performed Using Psychodrama Techniques on Adolescents' Conflict Resolution Skills

    ERIC Educational Resources Information Center

    Karatas, Zeynep

    2011-01-01

    The aim of this study is to examine the effects of group practice which is performed using psychodrama techniques on adolescents' conflict resolution skills. The subjects, for this study, were selected among the high school students who have high aggression levels and low problem solving levels attending Haci Zekiye Arslan High School, in Nigde.…

  5. Quantitative Techniques for the Identification of Social Sub-Groups in Natural Settings.

    ERIC Educational Resources Information Center

    Gariepy, Jean-Louis; Kindermann, Thomas

    Addressing a common problem in the analysis of social networks, this study describes quantitative techniques for identifying social subgroups using individual perceptions of social affinities within natural groups. Compared are four analytic methods for abstracting composite representations of sub-structures. These methods, formally evaluated…

  6. An Allegory of Addiction Recovery: Exploring the Performance of "Eumenides" by Aeschylus, as Adapted by 18 ANO Theatre Group

    ERIC Educational Resources Information Center

    Zontou, Zoe

    2013-01-01

    This paper examines the performance of the "Eumenides," as adapted and performed by 18 ANO theatre group. 18 ANO is the theatre group of the Drug dependence treatment unit 18 ANO of Attica's Psychiatric Hospital, which is based in Athens, Greece. Each year 18 ANO organises performances in the wider community with the aim of promoting…

  7. An Allegory of Addiction Recovery: Exploring the Performance of "Eumenides" by Aeschylus, as Adapted by 18 ANO Theatre Group

    ERIC Educational Resources Information Center

    Zontou, Zoe

    2013-01-01

    This paper examines the performance of the "Eumenides," as adapted and performed by 18 ANO theatre group. 18 ANO is the theatre group of the Drug dependence treatment unit 18 ANO of Attica's Psychiatric Hospital, which is based in Athens, Greece. Each year 18 ANO organises performances in the wider community with the aim of promoting…

  8. Group velocity delay spectroscopy technique for industrial monitoring of electron-beam-induced vapors

    NASA Astrophysics Data System (ADS)

    Benterou, Jerry J.; Berzins, Leon V.; Sharma, Manish N.

    1999-01-01

    Spectroscopic techniques are ideal for characterization and process control of electron beam generated beam generated vapor plumes. Absorption based techniques work well for a wide variety of applications, but are difficult to apply to optically dense or opaque vapor plumes. We describe an approach for monitoring optically dense vapor plumes that is based on measuring the group velocity delay of a laser beam near an optical transition to determine the vapor density. This technique has a larger dynamic range than absorption environment. Aluminum as chosen because of its prevalence in high performance aircraft alloys. In these applications, composition control of the alloy constituents is critical to the deposition process. Data is presented demonstrating the superior dynamic range of the measurement. In addition, preliminary data demonstrating aluminum vapor rate control in an electron beam evaporator is presented. Alternative applications where this technique could be useful are discussed.

  9. Adaptive gain, equalization, and wavelength stabilization techniques for silicon photonic microring resonator-based optical receivers

    NASA Astrophysics Data System (ADS)

    Palermo, Samuel; Chiang, Patrick; Yu, Kunzhi; Bai, Rui; Li, Cheng; Chen, Chin-Hui; Fiorentino, Marco; Beausoleil, Ray; Li, Hao; Shafik, Ayman; Titriku, Alex

    2016-03-01

    Interconnect architectures based on high-Q silicon photonic microring resonator devices offer a promising solution to address the dramatic increase in datacenter I/O bandwidth demands due to their ability to realize wavelength-division multiplexing (WDM) in a compact and energy efficient manner. However, challenges exist in realizing efficient receivers for these systems due to varying per-channel link budgets, sensitivity requirements, and ring resonance wavelength shifts. This paper reports on adaptive optical receiver design techniques which address these issues and have been demonstrated in two hybrid-integrated prototypes based on microring drop filters and waveguide photodetectors implemented in a 130nm SOI process and high-speed optical front-ends designed in 65nm CMOS. A 10Gb/s powerscalable architecture employs supply voltage scaling of a three inverter-stage transimpedance amplifier (TIA) that is adapted with an eye-monitor control loop to yield the necessary sensitivity for a given channel. As reduction of TIA input-referred noise is more critical at higher data rates, a 25Gb/s design utilizes a large input-stage feedback resistor TIA cascaded with a continuous-time linear equalizer (CTLE) that compensates for the increased input pole. When tested with a waveguide Ge PD with 0.45A/W responsivity, this topology achieves 25Gb/s operation with -8.2dBm sensitivity at a BER=10-12. In order to address microring drop filters sensitivity to fabrication tolerances and thermal variations, efficient wavelength-stabilization control loops are necessary. A peak-power-based monitoring loop which locks the drop filter to the input wavelength, while achieving compatibility with the high-speed TIA offset-correction feedback loop is implemented with a 0.7nm tuning range at 43μW/GHz efficiency.

  10. Preliminary Benchmarking of Plinian Eruption Simulations Using an Adaptive Grid Eulerian Technique

    NASA Astrophysics Data System (ADS)

    Peterson, A. H.; Ogden, D. E.; Wohletz, K. H.; Gisler, G.; Glatzmaier, G. A.

    2005-12-01

    The SAGE (SAIC Adaptive Grid Eulerian) code is an Eulerian hydrodynamics numerical technique employing adaptive mesh refinement at each cycle for every cell in 1-, 2-, and 3-D grids. It is primarily designed to solve high deformation flow of multiple materials and thus provides important capabilities for simulating volcanic eruption phenomena. Its multimaterial equation of state libraries includes a comprehensive coverage of water from solid ice through two-phase liquid and vapor to supercritical states approaching the Hugoniot, and extremely important aspect for simulating volcanic gases in general. In development are strength and failure rules that model non-Newtonian fluid/solid deformation. Because of the low effective sound speeds of eruptive mixtures, the facts that SAGE uses a piecewise, linear, multi-material, Gudonov numerical method to resolve shocks with second-order precision and exactly conserves mass, momentum, and energy, are a highly desirable attributes. Although this code has been previously used to simulate a volcanic eruption (i.e., eruption through a crater lake at Ruapehu volcano by Morrissey and Gisler), we are embarking in an effort to benchmark the code with CFDLib, a well-validated arbitrary Lagrangian-Eulerian code developed at Los Alamos National Laboratory. Through this effort we expect to better understand the strengths and weaknesses, the limitations, and provide direction for important enhancement of SAGE, and potentially provide the volcanological community with a powerful alternative to numerical codes currently available. At this point in our benchmarking, we demonstrate some results for fluid convection within a chamber and fluid jetting through a conduit.

  11. Flutter signal extracting technique based on FOG and self-adaptive sparse representation algorithm

    NASA Astrophysics Data System (ADS)

    Lei, Jian; Meng, Xiangtao; Xiang, Zheng

    2016-10-01

    Due to various moving parts inside, when a spacecraft runs in orbits, its structure could get a minor angular vibration, which results in vague image formation of space camera. Thus, image compensation technique is required to eliminate or alleviate the effect of movement on image formation and it is necessary to realize precise measuring of flutter angle. Due to the advantages such as high sensitivity, broad bandwidth, simple structure and no inner mechanical moving parts, FOG (fiber optical gyro) is adopted in this study to measure minor angular vibration. Then, movement leading to image degeneration is achieved by calculation. The idea of the movement information extracting algorithm based on self-adaptive sparse representation is to use arctangent function approximating L0 norm to construct unconstrained noisy-signal-aimed sparse reconstruction model and then solve the model by a method based on steepest descent algorithm and BFGS algorithm to estimate sparse signal. Then taking the advantage of the principle of random noises not able to be represented by linear combination of elements, useful signal and random noised are separated effectively. Because the main interference of minor angular vibration to image formation of space camera is random noises, sparse representation algorithm could extract useful information to a large extent and acts as a fitting pre-process method of image restoration. The self-adaptive sparse representation algorithm presented in this paper is used to process the measured minor-angle-vibration signal of FOG used by some certain spacecraft. By component analysis of the processing results, we can find out that the algorithm could extract micro angular vibration signal of FOG precisely and effectively, and can achieve the precision degree of 0.1".

  12. Effective grouping for energy and performance: Construction of adaptive, sustainable, and maintainable data storage

    NASA Astrophysics Data System (ADS)

    Essary, David S.

    The performance gap between processors and storage systems has been increasingly critical over the years. Yet the performance disparity remains, and further, storage energy consumption is rapidly becoming a new critical problem. While smarter caching and predictive techniques do much to alleviate this disparity, the problem persists, and data storage remains a growing contributor to latency and energy consumption. Attempts have been made at data layout maintenance, or intelligent physical placement of data, yet in practice, basic heuristics remain predominant. Problems that early studies sought to solve via layout strategies were proven to be NP-Hard, and data layout maintenance today remains more art than science. With unknown potential and a domain inherently full of uncertainty, layout maintenance persists as an area largely untapped by modern systems. But uncertainty in workloads does not imply randomness; access patterns have exhibited repeatable, stable behavior. Predictive information can be gathered, analyzed, and exploited to improve data layouts. Our goal is a dynamic, robust, sustainable predictive engine, aimed at improving existing layouts by replicating data at the storage device level. We present a comprehensive discussion of the design and construction of such a predictive engine, including workload evaluation, where we present and evaluate classical workloads as well as our own highly detailed traces collected over an extended period. We demonstrate significant gains through an initial static grouping mechanism, and compare against an optimal grouping method of our own construction, and further show significant improvement over competing techniques. We also explore and illustrate the challenges faced when moving from static to dynamic (i.e. online) grouping, and provide motivation and solutions for addressing these challenges. These challenges include metadata storage, appropriate predictive collocation, online performance, and physical placement

  13. Optimizing trial design in pharmacogenetics research: comparing a fixed parallel group, group sequential, and adaptive selection design on sample size requirements.

    PubMed

    Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit

    2013-01-01

    Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design.

  14. Adapt

    NASA Astrophysics Data System (ADS)

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  15. Introduction of online adaptive radiotherapy for bladder cancer through a multicentre clinical trial (Trans-Tasman Radiation Oncology Group 10.01): Lessons learned

    PubMed Central

    Pham, Daniel; Roxby, Paul; Kron, Tomas; Rolfo, Aldo; Foroudi, Farshad

    2013-01-01

    Online adaptive radiotherapy for bladder cancer is a novel radiotherapy technique that was found feasible in a pilot study at a single academic institution. In September 2010 this technique was opened as a multicenter study through the Trans-Tasman Radiation Oncology Group (TROG 10.01 bladder online adaptive radiotherapy treatment). Twelve centers across Australia and New-Zealand registered interest into the trial. A multidisciplinary team of radiation oncologists, radiation therapists and medical physicists represented the trial credentialing and technical support team. To provide timely activation and proper implementation of the adaptive technique the following key areas were addressed at each site: Staff education/training; Practical image guided radiotherapy assessment; provision of help desk and feedback. The trial credentialing process involved face-to-face training and technical problem solving via full day site visits. A dedicated “help-desk” team was developed to provide support for the clinical trial. 26% of the workload occurred at the credentialing period while the remaining 74% came post-center activation. The workload was made up of the following key areas; protocol clarification (36%), technical problems (46%) while staff training was less than 10%. Clinical trial credentialing is important to minimizing trial deviations. It should not only focus on site activation quality assurance but also provide ongoing education and technical support. PMID:23776308

  16. Developing a Framework for Objective Structured Clinical Examinations Using the Nominal Group Technique

    PubMed Central

    Crum, Matthew F.; White, Paul J.; Larson, Ian; Malone, Daniel T.; Manallack, David T.; Nicolazzo, Joseph A.; McDowell, Jennifer; Lim, Angelina S.; Kirkpatrick, Carl M.

    2016-01-01

    Objective. To use the nominal group technique to develop a framework to improve existing and develop new objective structured clinical examinations (OSCEs) within a four-year bachelor of pharmacy course. Design. Using the nominal group technique, a unique method of group interview that combines qualitative and quantitative data collection, focus groups were conducted with faculty members, practicing pharmacists, and undergraduate pharmacy students. Five draft OSCEs frameworks were suggested and participants were asked to generate new framework ideas. Assessment. Two focus groups (n=9 and n=7) generated nine extra frameworks. Two of these frameworks, one from each focus group, ranked highest (mean scores of 4.4 and 4.1 on a 5-point scale) and were similar in nature. The project team used these two frameworks to produce the final framework, which includes an OSCE in every year of the course, earlier implementation of teaching OSCEs, and the use of independent simulated patients who are not examiners. Conclusions. The new OSCE framework provides a consistent structure from course entry to exit and ensures graduates meet internship requirements. PMID:28090107

  17. Text grouping in patent analysis using adaptive K-means clustering algorithm

    NASA Astrophysics Data System (ADS)

    Shanie, Tiara; Suprijadi, Jadi; Zulhanif

    2017-03-01

    Patents are one of the Intellectual Property. Analyzing patent is one requirement in knowing well the development of technology in each country and in the world now. This study uses the patent document coming from the Espacenet server about Green Tea. Patent documents related to the technology in the field of tea is still widespread, so it will be difficult for users to information retrieval (IR). Therefore, it is necessary efforts to categorize documents in a specific group of related terms contained therein. This study uses titles patent text data with the proposed Green Tea in Statistical Text Mining methods consists of two phases: data preparation and data analysis stage. The data preparation phase uses Text Mining methods and data analysis stage is done by statistics. Statistical analysis in this study using a cluster analysis algorithm, the Adaptive K-Means Clustering Algorithm. Results from this study showed that based on the maximum value Silhouette, generate 87 clusters associated fifteen terms therein that can be utilized in the process of information retrieval needs.

  18. Extended motion adaptive signal integration technique for real-time image enhancement

    NASA Astrophysics Data System (ADS)

    Zhang, David C.; Piacentino, Michael; Chai, Sek

    2012-06-01

    Fast moving cameras often generate distorted and blurred images characterized by reduced sharpness (due to motion blur) and insufficient dynamic range. Reducing sensor integration times to minimize blur are often used but the light intensity and image Signal-to-Noise-Ratio (SNR) would be reduced as well. We propose a Motion Adaptive Signal Integration (MASI) algorithm that operates the sensor at a high frame rate, with real time alignment of individual image frames to form an enhanced quality video output. This technique enables signal integration in the digital domain, allowing both high SNR performance and low motion blur induced by the camera motion. We also show, in an Extended MASI (EMASI) algorithm, that high dynamic range can be achieved by combining high frame rate images of varying exposures. EMASI broadens the dynamic range of the sensor and extends the sensitivity to work in low light and noisy conditions. In a moving platform, it also reduces static noise in the sensor. This technology can be used in aerial surveillance, satellite imaging, border securities, wearable sensing, video conferencing and camera phone imaging applications.

  19. Many-Group Cross-Section Adjustment Techniques for Boiling Water Reactor Adaptive Simulation

    SciTech Connect

    Jessee, Matthew Anderson

    2011-01-01

    Computational capability has been developed to adjust multigroup neutron cross sections, including self-shielding correction factors, to improve the fidelity of boiling water reactor (BWR) core modeling and simulation. The method involves propagating multigroup neutron cross-section uncertainties through various BWR computational models to evaluate uncertainties in key core attributes such as core k{sub eff}, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then employed to adjust multigroup cross sections to minimize the disagreement between BWR core modeling predictions and observed (i.e., measured) plant data. For this paper, observed plant data are virtually simulated in the form of perturbed three-dimensional nodal power distributions with the perturbations sized to represent actual discrepancies between predictions and real plant data. The major focus of this work is to efficiently propagate multigroup neutron cross-section uncertainty through BWR lattice physics and core simulator calculations. The data adjustment equations are developed using a subspace approach that exploits the ill-conditioning of the multigroup cross-section covariance matrix to minimize computation and storage burden. Tikhonov regularization is also employed to improve the conditioning of the data adjustment equations. Expressions are also provided for posterior covariance matrices of both the multigroup cross-section and core attributes uncertainties.

  20. Assessment of a Novel Hybrid Delphi and Nominal Groups Technique to Evaluate Quality Indicators

    PubMed Central

    Davies, Sheryl; Romano, Patrick S; Schmidt, Eric M; Schultz, Ellen; Geppert, Jeffrey J; McDonald, Kathryn M

    2011-01-01

    Objective To test the implementation of a novel structured panel process in the evaluation of quality indicators. Data Source National panel of 64 clinicians rating usefulness of indicator applications in 2008–2009. Study Design Hybrid panel combined Delphi Group and Nominal Group (NG) techniques to evaluate 81 indicator applications. Principal Findings The Delphi Group and NG rated 56 percent of indicator applications similarly. Group assignment (Delphi versus Nominal) was not significantly associated with mean ratings, but specialty and research interests of panelists, and indicator factors such as denominator level and proposed use were. Rating distributions narrowed significantly in 20.8 percent of applications between review rounds. Conclusions The hybrid panel process facilitated information exchange and tightened rating distributions. Future assessments of this method might include a control panel. PMID:21790589

  1. Measurement of geologic nitrogen using mass spectrometry, colorimetry, and a newly adapted fluorometry technique

    NASA Astrophysics Data System (ADS)

    Johnson, Benjamin W.; Drage, Natashia; Spence, Jody; Hanson, Nova; El-Sabaawi, Rana; Goldblatt, Colin

    2017-03-01

    Long viewed as a mostly noble, atmospheric species, recent work demonstrates that nitrogen in fact cycles throughout the Earth system, including the atmosphere, biosphere, oceans, and solid Earth. Despite this new-found behaviour, more thorough investigation of N in geologic materials is limited due to its low concentration (one to tens of parts per million) and difficulty in analysis. In addition, N can exist in multiple species (NO3-, NH4+, N2, organic N), and determining which species is actually quantified can be difficult. In rocks and minerals, NH4+ is the most stable form of N over geologic timescales. As such, techniques designed to measure NH4+ can be particularly useful.We measured a number of geochemical rock standards using three different techniques: elemental analyzer (EA) mass spectrometry, colorimetry, and fluorometry. The fluorometry approach is a novel adaptation of a technique commonly used in biologic science, applied herein to geologic NH4+. Briefly, NH4+ can be quantified by HF dissolution, neutralization, addition of a fluorescing reagent, and analysis on a standard fluorometer. We reproduce published values for several rock standards (BCR-2, BHVO-2, and G-2), especially if an additional distillation step is performed. While it is difficult to assess the quality of each method, due to lack of international geologic N standards, fluorometry appears better suited to analyzing mineral-bound NH4+ than EA mass spectrometry and is a simpler, quicker alternative to colorimetry.To demonstrate a potential application of fluorometry, we calculated a continental crust N budget based on new measurements. We used glacial tills as a proxy for upper crust and analyzed several poorly constrained rock types (volcanics, mid-crustal xenoliths) to determine that the continental crust contains ˜ 2 × 1018 kg N. This estimate is consistent with recent budget estimates and shows that fluorometry is appropriate for large-scale questions where high sample throughput

  2. Modeling gravitational instabilities in self-gravitating protoplanetary disks with adaptive mesh refinement techniques

    NASA Astrophysics Data System (ADS)

    Lichtenberg, Tim; Schleicher, Dominik R. G.

    2015-07-01

    The astonishing diversity in the observed planetary population requires theoretical efforts and advances in planet formation theories. The use of numerical approaches provides a method to tackle the weaknesses of current models and is an important tool to close gaps in poorly constrained areas such as the rapid formation of giant planets in highly evolved systems. So far, most numerical approaches make use of Lagrangian-based smoothed-particle hydrodynamics techniques or grid-based 2D axisymmetric simulations. We present a new global disk setup to model the first stages of giant planet formation via gravitational instabilities (GI) in 3D with the block-structured adaptive mesh refinement (AMR) hydrodynamics code enzo. With this setup, we explore the potential impact of AMR techniques on the fragmentation and clumping due to large-scale instabilities using different AMR configurations. Additionally, we seek to derive general resolution criteria for global simulations of self-gravitating disks of variable extent. We run a grid of simulations with varying AMR settings, including runs with a static grid for comparison. Additionally, we study the effects of varying the disk radius. The physical settings involve disks with Rdisk = 10,100 and 300 AU, with a mass of Mdisk ≈ 0.05 M⊙ and a central object of subsolar mass (M⋆ = 0.646 M⊙). To validate our thermodynamical approach we include a set of simulations with a dynamically stable profile (Qinit = 3) and similar grid parameters. The development of fragmentation and the buildup of distinct clumps in the disk is strongly dependent on the chosen AMR grid settings. By combining our findings from the resolution and parameter studies we find a general lower limit criterion to be able to resolve GI induced fragmentation features and distinct clumps, which induce turbulence in the disk and seed giant planet formation. Irrespective of the physical extension of the disk, topologically disconnected clump features are only

  3. Automatic online adaptive radiation therapy techniques for targets with significant shape change: a feasibility study

    NASA Astrophysics Data System (ADS)

    Court, Laurence E.; Tishler, Roy B.; Petit, Joshua; Cormack, Robert; Chin, Lee

    2006-05-01

    This work looks at the feasibility of an online adaptive radiation therapy concept that would detect the daily position and shape of the patient, and would then correct the daily treatment to account for any changes compared with planning position. In particular, it looks at the possibility of developing algorithms to correct for large complicated shape change. For co-planar beams, the dose in an axial plane is approximately associated with the positions of a single multi-leaf collimator (MLC) pair. We start with a primary plan, and automatically generate several secondary plans with gantry angles offset by regular increments. MLC sequences for each plan are calculated keeping monitor units (MUs) and number of segments constant for a given beam (fluences are different). Bulk registration (3D) of planning and daily CT images gives global shifts. Slice-by-slice (2D) registration gives local shifts and rotations about the longitudinal axis for each axial slice. The daily MLC sequence is then created for each axial slice/MLC leaf pair combination, by taking the MLC positions from the pre-calculated plan with the nearest rotation, and shifting using a beam's-eye-view calculation to account for local linear shifts. A planning study was carried out using two head and neck region MR images of a healthy volunteer which were contoured to simulate a base-of-tongue treatment: one with the head straight (used to simulate the planning image) and the other with the head tilted to the left (the daily image). Head and neck treatment was chosen to evaluate this technique because of its challenging nature, with varying internal and external contours, and multiple degrees of freedom. Shape change was significant: on a slice-by-slice basis, local rotations in the daily image varied from 2 to 31°, and local shifts ranged from -0.2 to 0.5 cm and -0.4 to 0.0 cm in right-left and posterior-anterior directions, respectively. The adapted treatment gave reasonable target coverage (100%, 90

  4. Aquifer Storage and Recovery as a Viable Climate Change Adaptation Technique: Sustainable Development under the Current Regulatory Framework

    EPA Science Inventory

    A holistic investigation of aquifer storage and recovery (ASR) technique and application in the U.S. is being conducted as a part of the USEPA Water Resources Adaptation Program (WRAP). The research focus is to evaluate the potential of ASR application as a practical climate chan...

  5. Aquifer Storage and Recovery as a Viable Climate Change Adaptation Technique: Sustainable Development under the Current Regulatory Framework

    EPA Science Inventory

    A holistic investigation of aquifer storage and recovery (ASR) technique and application in the U.S. is being conducted as a part of the USEPA Water Resources Adaptation Program (WRAP). The research focus is to evaluate the potential of ASR application as a practical climate chan...

  6. Group velocity delay spectroscopy technique for industrial monitoring of electron beam induced vapors

    SciTech Connect

    Benterou, J J; Berzins, L V; Sharma, M N

    1998-09-24

    Spectroscopic techniques are ideal for characterization and process control of electron beam generated vapor plumes. Absorption based techniques work well for a wide variety of applications, but are difficult to apply to optically dense or opaque vapor plumes. We describe an approach for monitoring optically dense vapor plumes that is based on measuring the group velocity delay of a laser beam near an optical transition to determine the vapor density. This technique has a larger dynamic range than absorption spectroscopy. We describe our progress towards a robust system to monitor aluminum vaporization in an industrial environment. Aluminum was chosen because of its prevalence in high performance aircraft alloys. In these applications, composition control of the alloy constituents is critical to the deposition process. Data is presented demonstrating the superior dynamic range of the measurement. In addition, preliminary data demonstrating aluminum vapor rate control in an electron beam evaporator is presented. Alternative applications where this technique could be useful are discussed. Keywords: Group velocity delay spectroscopy, optical beat signal, optical heterodyne, index of refraction, laser absorption spectroscopy, external cavity diode laser (ECDL), electron beam vaporization, vapor density, vapor phase manufacturing, process control

  7. The conversation group: using group psychoanalytic techniques to resolve resistances of recently immigrated Chinese students to learning English in a high school setting.

    PubMed

    Zaretsky, Sheila

    2009-07-01

    Does group psychoanalytic theory and technique have an application in an ordinary high school classroom? In this article, the writer describes a research project in which she attempts to answer this question by applying the techniques with a group of recently immigrated Chinese students who wished to improve their spoken English.

  8. Flight control design using a blend of modern nonlinear adaptive and robust techniques

    NASA Astrophysics Data System (ADS)

    Yang, Xiaolong

    In this dissertation, the modern control techniques of feedback linearization, mu synthesis, and neural network based adaptation are used to design novel control laws for two specific applications: F/A-18 flight control and reusable launch vehicle (an X-33 derivative) entry guidance. For both applications, the performance of the controllers is assessed. As a part of a NASA Dryden program to develop and flight test experimental controllers for an F/A-18 aircraft, a novel method of combining mu synthesis and feedback linearization is developed to design longitudinal and lateral-directional controllers. First of all, the open-loop and closed-loop dynamics of F/A-18 are investigated. The production F/A-18 controller as well as the control distribution mechanism are studied. The open-loop and closed-loop handling qualities of the F/A-18 are evaluated using low order transfer functions. Based on this information, a blend of robust mu synthesis and feedback linearization is used to design controllers for a low dynamic pressure envelope of flight conditions. For both the longitudinal and the lateral-directional axes, a robust linear controller is designed for a trim point in the center of the envelope. Then by including terms to cancel kinematic nonlinearities and variations in the aerodynamic forces and moments over the flight envelope, a complete nonlinear controller is developed. In addition, to compensate for the model uncertainty, linearization error and variations between operating points, neural network based adaptation is added to the designed longitudinal controller. The nonlinear simulations, robustness and handling qualities analysis indicate that the performance is similar to or better than that for the production F/A-18 controllers. When the dynamic pressure is very low, the performance of both the experimental and the production flight controllers is degraded, but Level I handling qualities are still achieved. A new generation of Reusable Launch Vehicles

  9. Combined AIE/EBE/GMRES approach to incompressible flows. [Adaptive Implicit-Explicit/Grouped Element-by-Element/Generalized Minimum Residuals

    NASA Technical Reports Server (NTRS)

    Liou, J.; Tezduyar, T. E.

    1990-01-01

    Adaptive implicit-explicit (AIE), grouped element-by-element (GEBE), and generalized minimum residuals (GMRES) solution techniques for incompressible flows are combined. In this approach, the GEBE and GMRES iteration methods are employed to solve the equation systems resulting from the implicitly treated elements, and therefore no direct solution effort is involved. The benchmarking results demonstrate that this approach can substantially reduce the CPU time and memory requirements in large-scale flow problems. Although the description of the concepts and the numerical demonstration are based on the incompressible flows, the approach presented here is applicable to larger class of problems in computational mechanics.

  10. Combined AIE/EBE/GMRES approach to incompressible flows. [Adaptive Implicit-Explicit/Grouped Element-by-Element/Generalized Minimum Residuals

    NASA Technical Reports Server (NTRS)

    Liou, J.; Tezduyar, T. E.

    1990-01-01

    Adaptive implicit-explicit (AIE), grouped element-by-element (GEBE), and generalized minimum residuals (GMRES) solution techniques for incompressible flows are combined. In this approach, the GEBE and GMRES iteration methods are employed to solve the equation systems resulting from the implicitly treated elements, and therefore no direct solution effort is involved. The benchmarking results demonstrate that this approach can substantially reduce the CPU time and memory requirements in large-scale flow problems. Although the description of the concepts and the numerical demonstration are based on the incompressible flows, the approach presented here is applicable to larger class of problems in computational mechanics.

  11. Unitary group adapted state specific multireference perturbation theory: Formulation and pilot applications.

    PubMed

    Sen, Avijit; Sen, Sangita; Samanta, Pradipta Kumar; Mukherjee, Debashis

    2015-04-05

    We present here a comprehensive account of the formulation and pilot applications of the second-order perturbative analogue of the recently proposed unitary group adapted state-specific multireference coupled cluster theory (UGA-SSMRCC), which we call as the UGA-SSMRPT2. We also discuss the essential similarities and differences between the UGA-SSMRPT2 and the allied SA-SSMRPT2. Our theory, like its parent UGA-SSMRCC formalism, is size-extensive. However, because of the noninvariance of the theory with respect to the transformation among the active orbitals, it requires the use of localized orbitals to ensure size-consistency. We have demonstrated the performance of the formalism with a set of pilot applications, exploring (a) the accuracy of the potential energy surface (PES) of a set of small prototypical difficult molecules in their various low-lying states, using natural, pseudocanonical and localized orbitals and compared the respective nonparallelity errors (NPE) and the mean average deviations (MAD) vis-a-vis the full CI results with the same basis; (b) the efficacy of localized active orbitals to ensure and demonstrate manifest size-consistency with respect to fragmentation. We found that natural orbitals lead to the best overall PES, as evidenced by the NPE and MAD values. The MRMP2 results for individual states and of the MCQDPT2 for multiple states displaying avoided curve crossings are uniformly poorer as compared with the UGA-SSMRPT2 results. The striking aspect of the size-consistency check is the complete insensitivity of the sum of fragment energies with given fragment spin-multiplicities, which are obtained as the asymptotic limit of super-molecules with different coupled spins.

  12. Laser pulse design using optimal control theory-based adaptive simulated annealing technique: vibrational transitions and photo-dissociation

    NASA Astrophysics Data System (ADS)

    Nath, Bikram; Mondal, Chandan Kumar

    2014-08-01

    We have designed and optimised a combined laser pulse using optimal control theory-based adaptive simulated annealing technique for selective vibrational excitations and photo-dissociation. Since proper choice of pulses for specific excitation and dissociation phenomena is very difficult, we have designed a linearly combined pulse for such processes and optimised the different parameters involved in those pulses so that we can get an efficient combined pulse. The technique makes us free from choosing any arbitrary type of pulses and makes a ground to check their suitability. We have also emphasised on how we can improve the performance of simulated annealing technique by introducing an adaptive step length of the different variables during the optimisation processes. We have also pointed out on how we can choose the initial temperature for the optimisation process by introducing heating/cooling step to reduce the annealing steps so that the method becomes cost effective.

  13. Report of the B-factory Group: 1, Physics and techniques

    SciTech Connect

    Feldman, G.J.; Cassel, D.G.; Siemann, R.H.; Alam, M.S.; Aleksan, R.; Atwood, W.B.; Bartelt, J.; Bisognano, J.J.; Boyce, J.R.; Cline, D.B.

    1989-01-01

    The study of B meson decay appears to offer a unique opportunity to measure basic parameters of the Standard Model, probe for interactions mediated by higher mass particles, and investigate the origin of CP violation. These opportunities have been enhanced by the results of two measurements. The first is the measurement of a long B meson lifetime. In addition to allowing a simpler identification of B mesons and a measurement of the time of their decay, this observation implies that normal decays are suppressed, making rare decays more prevalent. The second measurement is that neutral B mesons are strongly mixed. This enhances the possibilities for studying CP violation in the B system. The CESR storage ring is likely to dominate the study of B physics in e{sup +}e{sup {minus}} annihilations for about the next five years. First, CESR has already reached a luminosity of 10{sup 32} cm{sup {minus}1} sec{sup {minus}1} and has plans for improvements which may increase the luminosity by a factor of about five. Second, a second-generation detector, CLEO II, will start running in 1989. Given this background, the main focus of this working group was to ask what is needed for the mid- to late-1990 s. Many laboratories are thinking about new facilities involving a variety of techniques. To help clarify the choices, we focused on one example of CP violation and estimated the luminosity required to measure it using different techniques. We will briefly describe the requirements for detectors matched to these techniques. In particular, we will give a conceptual design of a possible detector for asymmetric collisions at the {Upsilon}(4S) resonance, one of the attractive techniques which will emerge from this study. A discussion of accelerator technology issues for using these techniques forms the second half of the B-factory Group report, and it follows in these proceedings. 34 refs., 2 figs., 2 tabs.

  14. A micrometeorological technique for detecting small differences in methane emissions from two groups of cattle

    NASA Astrophysics Data System (ADS)

    Laubach, Johannes; Grover, Samantha P. P.; Pinares-Patiño, Cesar S.; Molano, German

    2014-12-01

    Potential approaches for reducing enteric methane (CH4) emissions from cattle will require verification of their efficacy at the paddock scale. We designed a micrometeorological approach to compare emissions from two groups of grazing cattle. The approach consists of measuring line-averaged CH4 mole fractions upwind and downwind of each group and using a backward-Lagrangian stochastic model to compute CH4 emission rates from the observed mole fractions, in combination with turbulence statistics measured by a sonic anemometer. With careful screening for suitable wind conditions, a difference of 10% in group emission rates could be detected. This result was corroborated by simultaneous measurements of daily CH4 emissions from each animal with the sulfur hexafluoride (SF6) tracer-ratio technique.

  15. Outcomes and Experiences of an Adapted Dialectic Behaviour Therapy Skills Training Group for People with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Crossland, Tom; Hewitt, Olivia; Walden, Sarah

    2017-01-01

    Background: A growing body of evidence supports the use of Dialectic Behaviour Therapy with people with an intellectual disability. Various adaptation have been used in studies exploring the efficacy of this intervention. Method: A Dialectic Behaviour Therapy DBT skills training group was attended by people with an intellectual disability and…

  16. The slot graft technique for foot and ankle arthrodesis in a high-risk patient group.

    PubMed

    Klein, Sandra E; Putnam, Ryan M; McCormick, Jeremy J; Johnson, Jeffrey E

    2011-07-01

    High rates of arthrodesis nonunion have been described in the ankle, hindfoot and midfoot in patients with significant risk factors. The purpose of this study was to evaluate fusion rates, risk of reoperation, postoperative pain scores and patient satisfaction for a slot graft inlay arthrodesis technique used in a high-risk group of foot and ankle patients. We retrospectively reviewed all ankle, hindfoot and midfoot arthrodeses by two foot and ankle surgeons in our institution between January 2000 and January 2009. Seventeen arthrodesis procedures in 16 patients using the slot graft technique were identified. Patient charts were reviewed for medical history, risk factors, previous surgery and postoperative complications. Time to union was evaluated on radiographs. Patients provided final followup by phone with an assessment of pain, overall satisfaction and use of orthotic or assistive devices. Union occurred in 13 arthrodesis procedures (77%) with an average time to union of 5 months. Postoperative infection occurred in one patient. Additional surgery was performed in nine patients. At final followup patients reported low pain scores (3 of 10) and high satisfaction (8 of 10). Fourteen of 15 patients contacted indicated that they would choose to undergo the procedure again. The slot graft arthrodesis technique provided satisfactory results in this small group of patients with a low complication rate. Patient satisfaction rates were high with low pain scores at an average of 62 months postoperatively.

  17. An innovations-based noise cancelling technique on inverse kepstrum whitening filter and adaptive FIR filter in beamforming structure.

    PubMed

    Jeong, Jinsoo

    2011-01-01

    This paper presents an acoustic noise cancelling technique using an inverse kepstrum system as an innovations-based whitening application for an adaptive finite impulse response (FIR) filter in beamforming structure. The inverse kepstrum method uses an innovations-whitened form from one acoustic path transfer function between a reference microphone sensor and a noise source so that the rear-end reference signal will then be a whitened sequence to a cascaded adaptive FIR filter in the beamforming structure. By using an inverse kepstrum filter as a whitening filter with the use of a delay filter, the cascaded adaptive FIR filter estimates only the numerator of the polynomial part from the ratio of overall combined transfer functions. The test results have shown that the adaptive FIR filter is more effective in beamforming structure than an adaptive noise cancelling (ANC) structure in terms of signal distortion in the desired signal and noise reduction in noise with nonminimum phase components. In addition, the inverse kepstrum method shows almost the same convergence level in estimate of noise statistics with the use of a smaller amount of adaptive FIR filter weights than the kepstrum method, hence it could provide better computational simplicity in processing. Furthermore, the rear-end inverse kepstrum method in beamforming structure has shown less signal distortion in the desired signal than the front-end kepstrum method and the front-end inverse kepstrum method in beamforming structure.

  18. Test techniques: A survey paper on cryogenic tunnels, adaptive wall test sections, and magnetic suspension and balance systems

    NASA Technical Reports Server (NTRS)

    Kilgore, Robert A.; Dress, David A.; Wolf, Stephen W. D.; Britcher, Colin P.

    1989-01-01

    The ability to get good experimental data in wind tunnels is often compromised by things seemingly beyond our control. Inadequate Reynolds number, wall interference, and support interference are three of the major problems in wind tunnel testing. Techniques for solving these problems are available. Cryogenic wind tunnels solve the problem of low Reynolds number. Adaptive wall test sections can go a long way toward eliminating wall interference. A magnetic suspension and balance system (MSBS) completely eliminates support interference. Cryogenic tunnels, adaptive wall test sections, and MSBS are surveyed. A brief historical overview is given and the present state of development and application in each area is described.

  19. Adaptive/learning control of large space structures - System identification techniques. [for multi-configuration flexible spacecraft

    NASA Technical Reports Server (NTRS)

    Thau, F. E.; Montgomery, R. C.

    1980-01-01

    Techniques developed for the control of aircraft under changing operating conditions are used to develop a learning control system structure for a multi-configuration, flexible space vehicle. A configuration identification subsystem that is to be used with a learning algorithm and a memory and control process subsystem is developed. Adaptive gain adjustments can be achieved by this learning approach without prestoring of large blocks of parameter data and without dither signal inputs which will be suppressed during operations for which they are not compatible. The Space Shuttle Solar Electric Propulsion (SEP) experiment is used as a sample problem for the testing of adaptive/learning control system algorithms.

  20. Nominal group technique: a brainstorming tool for identifying areas to improve pain management in hospitalized patients.

    PubMed

    Peña, Adolfo; Estrada, Carlos A; Soniat, Debbie; Taylor, Benjamin; Burton, Michael

    2012-01-01

    Pain management in hospitalized patients remains a priority area for improvement; effective strategies for consensus development are needed to prioritize interventions. To identify challenges, barriers, and perspectives of healthcare providers in managing pain among hospitalized patients. Qualitative and quantitative group consensus using a brainstorming technique for quality improvement-the nominal group technique (NGT). One medical, 1 medical-surgical, and 1 surgical hospital unit at a large academic medical center. Nurses, resident physicians, patient care technicians, and unit clerks. Responses and ranking to the NGT question: "What causes uncontrolled pain in your unit?" Twenty-seven health workers generated a total of 94 ideas. The ideas perceived contributing to a suboptimal pain control were grouped as system factors (timeliness, n = 18 ideas; communication, n = 11; pain assessment, n = 8), human factors (knowledge and experience, n = 16; provider bias, n = 8; patient factors, n = 19), and interface of system and human factors (standardization, n = 14). Knowledge, timeliness, provider bias, and patient factors were the top ranked themes. Knowledge and timeliness are considered main priorities to improve pain control. NGT is an efficient tool for identifying general and context-specific priority areas for quality improvement; teams of healthcare providers should consider using NGT to address their own challenges and barriers. Copyright © 2011 Society of Hospital Medicine.

  1. Respiration monitoring by Electrical Bioimpedance (EBI) Technique in a group of healthy males. Calibration equations.

    NASA Astrophysics Data System (ADS)

    Balleza, M.; Vargas, M.; Kashina, S.; Huerta, M. R.; Delgadillo, I.; Moreno, G.

    2017-01-01

    Several research groups have proposed the electrical impedance tomography (EIT) in order to analyse lung ventilation. With the use of 16 electrodes, the EIT is capable to obtain a set of transversal section images of thorax. In previous works, we have obtained an alternating signal in terms of impedance corresponding to respiration from EIT images. Then, in order to transform those impedance changes into a measurable volume signal a set of calibration equations has been obtained. However, EIT technique is still expensive to attend outpatients in basics hospitals. For that reason, we propose the use of electrical bioimpedance (EBI) technique to monitor respiration behaviour. The aim of this study was to obtain a set of calibration equations to transform EBI impedance changes determined at 4 different frequencies into a measurable volume signal. In this study a group of 8 healthy males was assessed. From obtained results, a high mathematical adjustment in the group calibrations equations was evidenced. Then, the volume determinations obtained by EBI were compared with those obtained by our gold standard. Therefore, despite EBI does not provide a complete information about impedance vectors of lung compared with EIT, it is possible to monitor the respiration.

  2. Determination of the phenolic-group capacities of humic substances by non-aqueous titration technique.

    PubMed

    Kirishima, Akira; Ohnishi, Takashi; Sato, Nobuaki; Tochiyama, Osamu

    2009-07-15

    The phenolic-group capacities of five humic substances, such as, the Aldrich humic acid, the humic and fulvic acids extracted from a soil, the humic and fulvic acids extracted from a peat have been precisely determined by the non-aqueous potentiometric titration technique. The titration by KOH in the mixed solvent of DMSO:2-propanol:water=80:19.3:0.7 at [K(+)]=0.02 M enabled to measure the potential change in a wide range of pOH (=-log[OH(-)]), and thus to determine the capacities of phenolic groups which could not be precisely determined in the aqueous titration. The results of the titration revealed that the mean protonation constants of the phenolic groups were nearly the same for all humic substances and close to that of phenol in the same medium, indicating that each phenolic-group in the humic substances is rather isolated and is not electronically affected by other affecting groups in the humic macromolecule.

  3. Nominal group technique for individuals with cognitive disability: a systematic review.

    PubMed

    Lakhani, Ali; Watling, David P; Zeeman, Heidi; Wright, Courtney J; Bishara, Jason

    2017-05-13

    Considering the perspectives of individuals with cognitive disability is important for their participation in their self-directed health care. The nominal group technique (NGT) has been identified as a method to gather opinions of people with cognitive disability; however, a synthesis of methodological considerations to undertake when employing the approach among people with cognitive disability is non-existent. A systematic review guided by the preferred reporting items for systematic review and meta-analysis protocols was undertaken. Five databases (CINAHL, ISI Web of Science, ProQuest Social Science Journals, Scopus, and MEDLINE) were searched for peer-reviewed literature published before September 2016. Methodological considerations pertaining to the four stages of the NGT- generating ideas, recording ideas, clarification, and ranking - were extracted from each study. Nine publications contributing to eight studies were included. Methodological considerations focused on (i) the number of participants within discussion groups, (ii) research question introduction, (iii) support individuals and accessible methods, (iv) ranking, and (v) researcher training and counselling services. The use of the NGT to gain the health care perspectives of adults with cognitive disability is promising. Conducting nominal group techniques informed by the methodological considerations identified within this review can work towards ensuring that the health care perspectives of people with cognitive disability are considered. Implications for rehabilitation The emergent policy move towards self-directed health care for people with disability requires that the health care perspectives of people with disability are considered. Effective consultation and discussion techniques are essential to gain the health care perspectives of people with cognitive disability. After undertaking methodological considerations, the NGT can be an effective approach towards gaining the health care

  4. Adaptive Meshing Techniques for Viscous Flow Calculations on Mixed Element Unstructured Meshes

    NASA Technical Reports Server (NTRS)

    Mavriplis, D. J.

    1997-01-01

    An adaptive refinement strategy based on hierarchical element subdivision is formulated and implemented for meshes containing arbitrary mixtures of tetrahendra, hexahendra, prisms and pyramids. Special attention is given to keeping memory overheads as low as possible. This procedure is coupled with an algebraic multigrid flow solver which operates on mixed-element meshes. Inviscid flows as well as viscous flows are computed an adaptively refined tetrahedral, hexahedral, and hybrid meshes. The efficiency of the method is demonstrated by generating an adapted hexahedral mesh containing 3 million vertices on a relatively inexpensive workstation.

  5. Identification of Strategies to Facilitate Organ Donation among African Americans using the Nominal Group Technique

    PubMed Central

    Qu, Haiyan; Shewchuk, Richard; Mannon, Roslyn B.; Gaston, Robert; Segev, Dorry L.; Mannon, Elinor C.; Martin, Michelle Y.

    2015-01-01

    Background and objectives African Americans are disproportionately affected by ESRD, but few receive a living donor kidney transplant. Surveys assessing attitudes toward donation have shown that African Americans are less likely to express a willingness to donate their own organs. Studies aimed at understanding factors that may facilitate the willingness of African Americans to become organ donors are needed. Design, setting, participants, & measurements A novel formative research method was used (the nominal group technique) to identify and prioritize strategies for facilitating increases in organ donation among church-attending African Americans. Four nominal group technique panel interviews were convened (three community and one clergy). Each community panel represented a distinct local church; the clergy panel represented five distinct faith-based denominations. Before nominal group technique interviews, participants completed a questionnaire that assessed willingness to become a donor; 28 African-American adults (≥19 years old) participated in the study. Results In total, 66.7% of participants identified knowledge- or education-related strategies as most important strategies in facilitating willingness to become an organ donor, a view that was even more pronounced among clergy. Three of four nominal group technique panels rated a knowledge-based strategy as the most important and included strategies, such as information on donor involvement and donation-related risks; 29.6% of participants indicated that they disagreed with deceased donation, and 37% of participants disagreed with living donation. Community participants’ reservations about becoming an organ donor were similar for living (38.1%) and deceased (33.4%) donation; in contrast, clergy participants were more likely to express reservations about living donation (33.3% versus 16.7%). Conclusions These data indicate a greater opposition to living donation compared with donation after one’s death

  6. Identification of strategies to facilitate organ donation among African Americans using the nominal group technique.

    PubMed

    Locke, Jayme E; Qu, Haiyan; Shewchuk, Richard; Mannon, Roslyn B; Gaston, Robert; Segev, Dorry L; Mannon, Elinor C; Martin, Michelle Y

    2015-02-06

    African Americans are disproportionately affected by ESRD, but few receive a living donor kidney transplant. Surveys assessing attitudes toward donation have shown that African Americans are less likely to express a willingness to donate their own organs. Studies aimed at understanding factors that may facilitate the willingness of African Americans to become organ donors are needed. A novel formative research method was used (the nominal group technique) to identify and prioritize strategies for facilitating increases in organ donation among church-attending African Americans. Four nominal group technique panel interviews were convened (three community and one clergy). Each community panel represented a distinct local church; the clergy panel represented five distinct faith-based denominations. Before nominal group technique interviews, participants completed a questionnaire that assessed willingness to become a donor; 28 African-American adults (≥19 years old) participated in the study. In total, 66.7% of participants identified knowledge- or education-related strategies as most important strategies in facilitating willingness to become an organ donor, a view that was even more pronounced among clergy. Three of four nominal group technique panels rated a knowledge-based strategy as the most important and included strategies, such as information on donor involvement and donation-related risks; 29.6% of participants indicated that they disagreed with deceased donation, and 37% of participants disagreed with living donation. Community participants' reservations about becoming an organ donor were similar for living (38.1%) and deceased (33.4%) donation; in contrast, clergy participants were more likely to express reservations about living donation (33.3% versus 16.7%). These data indicate a greater opposition to living donation compared with donation after one's death among African Americans and suggest that improving knowledge about organ donation, particularly

  7. Gender and homosexuality attitudes across religious groups from the 1970s to 2014: Similarity, distinction, and adaptation.

    PubMed

    Schnabel, Landon

    2016-01-01

    This study uses General Social Survey data to compare gender and homosexuality across American religious groups from the 1970s to 2014, examining three possible patterns for how evangelical attitudes relate to those of other groups: (1) they are similar; (2) they are different, but move together over time; (3) they are different and converge or diverge over time. Evangelical gender attitudes regarding work and family issues are more conservative than those of all other groups, but are adaptive to broad trends, changing at a rate similar to those of other groups. Evangelical attitudes toward the morality of homosexuality and same-sex marriage are more conservative than those of all other religious groups, and their rate of change is slower over time. Separate trends on the two issues suggest that gender and sexuality attitude change is decoupled, especially among evangelicals who are adapting more on gender while increasingly distinguishing themselves on same-sex relationships. A three-stage process of religious tension appears to characterize evangelical identity-building: (1) similarity, (2) distinction, and (3) adaptation. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. ADAPTATION OF CRACK GROWTH DETECTION TECHNIQUES TO US MATERIAL TEST REACTORS

    SciTech Connect

    A. Joseph Palmer; Sebastien P. Teysseyre; Kurt L. Davis; Gordon Kohse; Yakov Ostrovsky; David M. Carpenter; Joy L. Rempe

    2015-04-01

    A key component in evaluating the ability of Light Water Reactors to operate beyond 60 years is characterizing the degradation of materials exposed to radiation and various water chemistries. Of particular concern is the response of reactor materials to Irradiation Assisted Stress Corrosion Cracking (IASCC). Some test reactors outside the United States, such as the Halden Boiling Water Reactor (HBWR), have developed techniques to measure crack growth propagation during irradiation. The basic approach is to use a custom-designed compact loading mechanism to stress the specimen during irradiation, while the crack in the specimen is monitored in-situ using the Direct Current Potential Drop (DCPD) method. In 2012 the US Department of Energy commissioned the Idaho National Laboratory and the MIT Nuclear Reactor Laboratory (MIT NRL) to take the basic concepts developed at the HBWR and adapt them to a test rig capable of conducting in-pile IASCC tests in US Material Test Reactors. The first two and half years of the project consisted of designing and testing the loader mechanism, testing individual components of the in-pile rig and electronic support equipment, and autoclave testing of the rig design prior to insertion in the MIT Reactor. The load was applied to the specimen by means of a scissor like mechanism, actuated by a miniature metal bellows driven by pneumatic pressure and sized to fit within the small in-core irradiation volume. In addition to the loader design, technical challenges included developing robust connections to the specimen for the applied current and voltage measurements, appropriate ceramic insulating materials that can endure the LWR environment, dealing with the high electromagnetic noise environment of a reactor core at full power, and accommodating material property changes in the specimen, due primarily to fast neutron damage, which change the specimen resistance without additional crack growth. The project culminated with an in

  9. Electrical hand tools and techniques: A compilation. [utilization of space technology for tools and adapters

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Space technology utilization for developing tools, adapters, and fixtures and procedures for assembling, installing, and servicing electrical components and equipment are discussed. Some of the items considered are: (1) pivotal screwdriver, (2) termination locator tool for shielded cables, (3) solder application tools, (4) insulation and shield removing tool, and (5) torque wrench adapter for cable connector engaging ring. Diagrams of the various tools and devices are provided.

  10. The adaptive statistical iterative reconstruction-V technique for radiation dose reduction in abdominal CT: comparison with the adaptive statistical iterative reconstruction technique.

    PubMed

    Kwon, Heejin; Cho, Jinhan; Oh, Jongyeong; Kim, Dongwon; Cho, Junghyun; Kim, Sanghyun; Lee, Sangyun; Lee, Jihyun

    2015-10-01

    To investigate whether reduced radiation dose abdominal CT images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V) compromise the depiction of clinically competent features when compared with the currently used routine radiation dose CT images reconstructed with ASIR. 27 consecutive patients (mean body mass index: 23.55 kg m(-2) underwent CT of the abdomen at two time points. At the first time point, abdominal CT was scanned at 21.45 noise index levels of automatic current modulation at 120 kV. Images were reconstructed with 40% ASIR, the routine protocol of Dong-A University Hospital. At the second time point, follow-up scans were performed at 30 noise index levels. Images were reconstructed with filtered back projection (FBP), 40% ASIR, 30% ASIR-V, 50% ASIR-V and 70% ASIR-V for the reduced radiation dose. Both quantitative and qualitative analyses of image quality were conducted. The CT dose index was also recorded. At the follow-up study, the mean dose reduction relative to the currently used common radiation dose was 35.37% (range: 19-49%). The overall subjective image quality and diagnostic acceptability of the 50% ASIR-V scores at the reduced radiation dose were nearly identical to those recorded when using the initial routine-dose CT with 40% ASIR. Subjective ratings of the qualitative analysis revealed that of all reduced radiation dose CT series reconstructed, 30% ASIR-V and 50% ASIR-V were associated with higher image quality with lower noise and artefacts as well as good sharpness when compared with 40% ASIR and FBP. However, the sharpness score at 70% ASIR-V was considered to be worse than that at 40% ASIR. Objective image noise for 50% ASIR-V was 34.24% and 46.34% which was lower than 40% ASIR and FBP. Abdominal CT images reconstructed with ASIR-V facilitate radiation dose reductions of to 35% when compared with the ASIR. This study represents the first clinical research experiment to use ASIR-V, the newest version of

  11. Techniques for rapid quantitative assessment of activity levels in small-group tutorials.

    PubMed

    Prinz, J F; Yip, H Y; Tipoe, G L; Lucas, P W; Lenstrup, M

    1998-07-01

    Two techniques for the rapid quantitative analysis of student participation in small-group teaching were investigated. In the first approach an observer, who also acted as a 'critical friend', recorded the length of individual contributions using a computer keyboard as a simple timing device. In the second approach, small-group sessions were recorded with a portable stereophonic audiotape recorder. The teacher was recorded on one channel, all students on the other. A computer program produced automated analysis of these small group interactions by computing relative amount of speech on each channel. Simple analysis produced automatically by the programs revealed the overall style of the tutorial--variably 'mini-lectures' by teachers with very little participation by the student body, rapid 'question and answer' sessions with about equal teacher/student body involvement or 'mini-presentations' by students with the teacher offering sparse comments in the manner of a facilitator. By presenting results in a graphic format, teachers can be given rapid objective feedback on their teaching style. Coupled with short verbal/non-verbal quizzes at the end of tutorials and information from other assessments, the value of using levels of participation as a measure of the efficiency of such small-group sessions can itself be assessed.

  12. Primary plate identification of group A beta-hemolytic streptococci utilizing a two-disk technique.

    PubMed Central

    Baron, E J; Gates, J W

    1979-01-01

    A two-disk system is described which allows primary plate identification of group A beta-hemolytic streptococci. Group A beta-hemolytic streptococci could be visualized on primary throat culture plates by using trimethoprim-sulfamethoxazole to inhibit normal flora. In the heavily inoculated area of Trypticase soy agar plates containing 5% sheep blood, a 25-microgram/ml trimethoprim-sulfamethoxazole disk was placed contiguous to a 0.04-U bacitracin disk. A total of 259 throat specimens were examined with this two-disk system. The swabs from these throat specimens were incubated in Todd-Hewitt broth. The bacterial pellet from the broths was stained by fluorescent antibody as a control. Of the cultures that were determined to be positive on the plates, 75% could be read unequivocally after overnight incubation, whereas the remaining 25% required subculture. The plates recovered 91% of the cultures which were considered as true positives by the broth-fluorescent-antibody technique. This method provided a significant savings in time compared with standard plate methods and in cost of materials compared with broth-fluorescent-antibody methods. This technique is particularly valuable for producing rapid results in laboratories where fluorescence microscopy would not be cost-effective. Images PMID:387811

  13. Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

    ERIC Educational Resources Information Center

    Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

    2016-01-01

    Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

  14. The Adaptation of Naval Enlistees Scoring in Mental Group 4 on the Armed Forces Qualification Test.

    ERIC Educational Resources Information Center

    Plag, John A.; And Others

    This report presents findings from a study evaluating differences in the adaptation of "average" and mentally marginal sailors during four years of military service. Sailors with Armed Forces Qualification Test (AFQT) scores of 50 are significantly superior to Category 4 enlistees on military performance measures which stress cognitive…

  15. Five Methods to Score the Teacher Observation of Classroom Adaptation Checklist and to Examine Group Differences

    ERIC Educational Resources Information Center

    Wang, Ze; Rohrer, David; Chuang, Chi-ching; Fujiki, Mayo; Herman, Keith; Reinke, Wendy

    2015-01-01

    This study compared 5 scoring methods in terms of their statistical assumptions. They were then used to score the Teacher Observation of Classroom Adaptation Checklist, a measure consisting of 3 subscales and 21 Likert-type items. The 5 methods used were (a) sum/average scores of items, (b) latent factor scores with continuous indicators, (c)…

  16. The Adaptation of Naval Enlistees Scoring in Mental Group 4 on the Armed Forces Qualification Test.

    ERIC Educational Resources Information Center

    Plag, John A.; And Others

    This report presents findings from a study evaluating differences in the adaptation of "average" and mentally marginal sailors during four years of military service. Sailors with Armed Forces Qualification Test (AFQT) scores of 50 are significantly superior to Category 4 enlistees on military performance measures which stress cognitive…

  17. Adaptation to College for Students with and without Disabilities: Group Differences and Predictors

    ERIC Educational Resources Information Center

    Adams, Katharine S.; Proctor, Briley E.

    2010-01-01

    This study investigated differences between attributional style and student adaptation to college for students with and without disabilities. In terms of attributional style, the students with disabilities demonstrated a more internal, stable, and global attributional style for both positive events and negative events. In terms of student…

  18. Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

    ERIC Educational Resources Information Center

    Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

    2016-01-01

    Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

  19. Five Methods to Score the Teacher Observation of Classroom Adaptation Checklist and to Examine Group Differences

    ERIC Educational Resources Information Center

    Wang, Ze; Rohrer, David; Chuang, Chi-ching; Fujiki, Mayo; Herman, Keith; Reinke, Wendy

    2015-01-01

    This study compared 5 scoring methods in terms of their statistical assumptions. They were then used to score the Teacher Observation of Classroom Adaptation Checklist, a measure consisting of 3 subscales and 21 Likert-type items. The 5 methods used were (a) sum/average scores of items, (b) latent factor scores with continuous indicators, (c)…

  20. Effects of planned group interactions on the social adaptation of individuals with an intestinal stoma: a quantitative study.

    PubMed

    Karabulut, Hatice K; Dinç, Leyla; Karadag, Ayişe

    2014-10-01

    To investigate the effects of a planned group interaction method on the social adjustment of individuals with an intestinal stoma. Individuals with a stoma often experience physiological, psychological and social problems that affect their social adaptation. Quasi-experimental. The population included ileostomy and colostomy patients registered at the Gazi University Health Research and Implementation Centre Stoma therapy Unit between September 2011-June 2012. They were assigned to experimental (n = 23) and control (n = 27) groups based on their willingness to attend planned group interaction meetings. Experimental group members participated in the 'planned group interaction method' for six weeks. Control group members only received routine care services. Weekly group interaction meetings lasted for average of 90 minutes. The Ostomy Adjustment Inventory and Psychosocial Adjustment to Illness Scale-Self-Report Scale were administered to experimental group members on three occasions: prior to the first group meeting, after the six-week meeting process ended and during the first month after group meetings ended. Control group evaluations were conducted simultaneously. Experimental group members' ostomy adjustment mean scores after planned group interaction meetings gradually increased. No changes occurred in the control group's average scores. The experimental and control groups' average psychosocial adjustment scores eventually changed and showed a tendency towards adjustment. Experimental group members aged 51-60 and 61-70, who were married, had primary and higher education, had permanent stomas, had stomas for periods between 12 months or less and 61 months and longer and had sufficient stoma care knowledge demonstrated higher adjustment values (p < 0·05). Furthermore, experimental group members reported they received psychological support during interactions and learned how to solve problems encountered in stoma care and daily life. Planned group interactions

  1. Manipulating the affiliative interactions of group-housed rhesus macaques using positive reinforcement training techniques.

    PubMed

    Schapiro, S J; Perlman, J E; Boudreau, B A

    2001-11-01

    Social housing, whether continuous, intermittent, or partial contact, typically provides many captive primates with opportunities to express affiliative behaviors, important components of the species-typical behavioral repertoire. Positive reinforcement training techniques have been successfully employed to shape many behaviors important for achieving primate husbandry goals. The present study was conducted to determine whether positive reinforcement training techniques could also be employed to alter levels of affiliative interactions among group-housed rhesus macaques. Twenty-eight female rhesus were divided into high (n = 14) and low (n = 14) affiliators based on a median split of the amount of time they spent affiliating during the baseline phase of the study. During the subsequent training phase, half of the low affiliators (n = 7) were trained to increase their time spent affiliating, and half of the high affiliators (n = 7) were trained to decrease their time spent affiliating. Trained subjects were observed both during and outside of training sessions. Low affiliators significantly increased the amount of time they spent affiliating, but only during nontraining sessions. High affiliators on the other hand, significantly decreased the amount of time they spent affiliating, but only during training sessions. These data suggest that positive reinforcement techniques can be used to alter the affiliative behavior patterns of group-housed, female rhesus monkeys, although the two subgroups of subjects responded differently to the training process. Low affiliators changed their overall behavioral repertoire, while high affiliators responded to the reinforcement contingencies of training, altering their proximity patterns but not their overall behavior patterns. Thus, positive reinforcement training can be used not only as a means to promote species-typical or beneficial behavior patterns, but also as an important experimental manipulation to facilitate systematic

  2. Improving adaptive generalized polynomial chaos method to solve nonlinear random differential equations by the random variable transformation technique

    NASA Astrophysics Data System (ADS)

    Cortés, J.-C.; Romero, J.-V.; Roselló, M.-D.; Villanueva, R.-J.

    2017-09-01

    Generalized polynomial chaos (gPC) is a spectral technique in random space to represent random variables and stochastic processes in terms of orthogonal polynomials of the Askey scheme. One of its most fruitful applications consists of solving random differential equations. With gPC, stochastic solutions are expressed as orthogonal polynomials of the input random parameters. Different types of orthogonal polynomials can be chosen to achieve better convergence. This choice is dictated by the key correspondence between the weight function associated to orthogonal polynomials in the Askey scheme and the probability density functions of standard random variables. Otherwise, adaptive gPC constitutes a complementary spectral method to deal with arbitrary random variables in random differential equations. In its original formulation, adaptive gPC requires that both the unknowns and input random parameters enter polynomially in random differential equations. Regarding the inputs, if they appear as non-polynomial mappings of themselves, polynomial approximations are required and, as a consequence, loss of accuracy will be carried out in computations. In this paper an extended version of adaptive gPC is developed to circumvent these limitations of adaptive gPC by taking advantage of the random variable transformation method. A number of illustrative examples show the superiority of the extended adaptive gPC for solving nonlinear random differential equations. In addition, for the sake of completeness, in all examples randomness is tackled by nonlinear expressions.

  3. Radiation treatment for the right naris in a pediatric anesthesia patient using an adaptive oral airway technique

    SciTech Connect

    Sponseller, Patricia Pelly, Nicole; Trister, Andrew; Ford, Eric; Ermoian, Ralph

    2015-10-01

    Radiation therapy for pediatric patients often includes the use of intravenous anesthesia with supplemental oxygen delivered via the nasal cannula. Here, we describe the use of an adaptive anesthesia technique for electron irradiation of the right naris in a preschool-aged patient treated under anesthesia. The need for an intranasal bolus plug precluded the use of standard oxygen supplementation. This novel technique required the multidisciplinary expertise of anesthesiologists, radiation therapists, medical dosimetrists, medical physicists, and radiation oncologists to ensure a safe and reproducible treatment course.

  4. Data Selection for Fast Projection Techniques Applied to Adaptive Nulling: A Comparative Study of Performance

    DTIC Science & Technology

    1991-12-01

    point de vue d’annulation des brouilleurs, le dernier 6tant moins rapide mais donnant une meilleure annulation. En effet , ces algorithmes donnent un...techniques avec celui de la technique "sample matrix inversion ou SMI" pour trois scenarios diffdrents; ces trois derniers ddmontrent les effets du nombre de...eigenvector analysis, such as the MUSIC technique [2], are effective for both interference suppression and spectral estimation. These techniques yield

  5. Centimeter-level group-delay altimetric precision using the new PARIS interferometric technique

    NASA Astrophysics Data System (ADS)

    Cardellach, E.; Nogues-Correig, O.; Ribo, S.; Rius, A.; Camps, A.; van der Marel, H.; Martin-Neira, M.

    2010-12-01

    SPIRENT equipment under different configurations. The preliminary analysis has resulted in the detection of 1-cm delay-jumps, using 33 group-delay observables of 1 second, with an associated 1-second dispersion of the order of 2-cm. A second experiment was conducted using real reflected signals obtained from a bridge ( ˜18 m) over estuary waters. The analysis shows 2-day repeatability, a delay pattern consistent with a simple model for multiple simultaneous satellite captures, which results in preliminary altimetric precisions of σ H ˜7cm at 1-second observation time. The altimetric results are in agreement with a RADAC WaveGuide collocated at the experimental site. The new technique, its proof-of-concept instrument and latest analysis results will be presented.

  6. A Rapid Model Adaptation Technique for Emotional Speech Recognition with Style Estimation Based on Multiple-Regression HMM

    NASA Astrophysics Data System (ADS)

    Ijima, Yusuke; Nose, Takashi; Tachibana, Makoto; Kobayashi, Takao

    In this paper, we propose a rapid model adaptation technique for emotional speech recognition which enables us to extract paralinguistic information as well as linguistic information contained in speech signals. This technique is based on style estimation and style adaptation using a multiple-regression HMM (MRHMM). In the MRHMM, the mean parameters of the output probability density function are controlled by a low-dimensional parameter vector, called a style vector, which corresponds to a set of the explanatory variables of the multiple regression. The recognition process consists of two stages. In the first stage, the style vector that represents the emotional expression category and the intensity of its expressiveness for the input speech is estimated on a sentence-by-sentence basis. Next, the acoustic models are adapted using the estimated style vector, and then standard HMM-based speech recognition is performed in the second stage. We assess the performance of the proposed technique in the recognition of simulated emotional speech uttered by both professional narrators and non-professional speakers.

  7. Role of span length in the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques

    PubMed Central

    Zhou, Ying; Li, Yong; Ma, Xiao; Huang, Yiqing

    2017-01-01

    PURPOSE This study evaluated the effect of span length on the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques. MATERIALS AND METHODS Models with two solid abutment analogs at different inter-abutment distances were digitized using a laboratory scanner. Frameworks of two-, three-, and four-unit fixed prostheses were designed by a computer. Six dots with a diameter of 0.2 mm were preset on the surface of each framework. A total of 54 implant-supported cobalt chromium frameworks were fabricated by milling, selective laser melting (SLM), and cast techniques. The frameworks were scanned and exported as Stereolithography files. Distances between two dots in X, Y, and Z coordinates were measured in both the designed and fabricated frameworks. Marginal gaps between the framework and the abutments were also evaluated by impression replica method. RESULTS In terms of distance measurement, significant differences were found between three- and four-unit frameworks, as well as between two- and four-unit frameworks prepared by milling technique (P<.05). Significant differences were also noted between two- and three-unit frameworks, as well as between two- and four-unit frameworks prepared by cast technique (P<.05). The milling technique presented smaller differences than the SLM technique, and the SLM technique showed smaller differences than the cast technique at any unit prostheses (P<.05). Evaluation with the impression replica method indicated significant differences among the span lengths for any fabrication method (P<.05), as well as among the fabrication methods at any unit prostheses (P<.05). CONCLUSION The adaptation of implant-supported cobalt chromium frameworks was affected by the span length and fabrication method. PMID:28435622

  8. Role of span length in the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques.

    PubMed

    Zhou, Ying; Li, Yong; Ma, Xiao; Huang, Yiqing; Wang, Jiawei

    2017-04-01

    This study evaluated the effect of span length on the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques. Models with two solid abutment analogs at different inter-abutment distances were digitized using a laboratory scanner. Frameworks of two-, three-, and four-unit fixed prostheses were designed by a computer. Six dots with a diameter of 0.2 mm were preset on the surface of each framework. A total of 54 implant-supported cobalt chromium frameworks were fabricated by milling, selective laser melting (SLM), and cast techniques. The frameworks were scanned and exported as Stereolithography files. Distances between two dots in X, Y, and Z coordinates were measured in both the designed and fabricated frameworks. Marginal gaps between the framework and the abutments were also evaluated by impression replica method. In terms of distance measurement, significant differences were found between three- and four-unit frameworks, as well as between two- and four-unit frameworks prepared by milling technique (P<.05). Significant differences were also noted between two- and three-unit frameworks, as well as between two- and four-unit frameworks prepared by cast technique (P<.05). The milling technique presented smaller differences than the SLM technique, and the SLM technique showed smaller differences than the cast technique at any unit prostheses (P<.05). Evaluation with the impression replica method indicated significant differences among the span lengths for any fabrication method (P<.05), as well as among the fabrication methods at any unit prostheses (P<.05). The adaptation of implant-supported cobalt chromium frameworks was affected by the span length and fabrication method.

  9. Identifying competencies required for medication prescribing for general practice residents: a nominal group technique study

    PubMed Central

    2014-01-01

    Background Teaching of medication prescribing is a specific challenge in general practice curriculum. The aim of this study was to identify and rank the competencies required for prescribing medication for general practice residents in France. Methods Qualitative consensus study using the nominal group technique. We invited different stakeholders of the general practice curriculum and medication use in primary care to a series of meetings. The nominal group technique allowed for the quick development of a list of consensual and ranked answers to the following question: “At the end of their general practice curriculum, in terms of medication prescribing, what should residents be able to do?”. Results Four meetings were held that involved a total of 31 participants, enabling the creation of a final list of 29 ranked items, grouped in 4 domains. The four domains identified were ‘pharmacology’, ‘regulatory standards’, ‘therapeutics’, and ‘communication (both with patients and healthcare professionals)’. Overall, the five items the most highly valued across the four meetings were: ‘write a legible and understandable prescription’, ‘identify specific populations’, ‘prescribe the doses and durations following the indication’, ‘explain a lack of medication prescription to the patient’, ‘decline inappropriate medication request’. The ‘communication skills’ domain was the domain with the highest number of items (10 items), and with the most highly-valued items. Conclusion The study results suggest a need for developing general practice residents’ communication skills regarding medication prescribing. PMID:25084813

  10. Evaluation and comparison of an adaptive method technique for improved performance of linear Fresnel secondary designs

    DOE PAGES

    Hack, Madeline; Zhu, Guangdong; Wendelin, Timothy J.

    2017-09-13

    As a line-focus concentrating solar power (CSP) technology, linear Fresnel collectors have the potential to become a low-cost solution for electricity production and a variety of thermal energy applications. However, this technology often suffers from relatively low performance. A secondary reflector is a key component used to improve optical performance of a linear Fresnel collector. The shape of a secondary reflector is particularly critical in determining solar power captured by the absorber tube(s), and thus, the collector's optical performance. However, to the authors' knowledge, no well-established process existed to derive the optimal secondary shape prior to the development of amore » new adaptive method to optimize the secondary reflector shape. The new adaptive method does not assume any pre-defined analytical form; rather, it constitutes an optimum shape through an adaptive process by maximizing the energy collection onto the absorber tube. In this paper, the adaptive method is compared with popular secondary-reflector designs with respect to a collector's optical performance under various scenarios. For the first time, a comprehensive, in-depth comparison was conducted on all popular secondary designs for CSP applications. In conclusion, it is shown that the adaptive design exhibits the best optical performance.« less

  11. Program planning for a community pharmacy residency support service using the nominal group technique.

    PubMed

    Rupp, Michael T

    2002-01-01

    To define programmatic objectives and initial operational priorities for CommuniRes, a university-based education and support service designed to help community pharmacists successfully implement and sustain community pharmacy residency programs (CPRPs). Advisory committee of nationally recognized experts in CPRPs in a small-group planning session. CPRPs are postgraduate clinical training experiences conducted in chain and independent community pharmacies. The nominal group technique (NGT), a structured approach to group planning and decision making, was used to identify and prioritize the needs of CPRPs. Results of the NGT exercise were used as input to a brainstorming session that defined specific CommuniRes services and resources that must be developed to meet high priority needs of CPRPs. Group consensus on the priority needs of CPRPs was determined through rank order voting. The advisory committee identified 20 separate CPRP needs that it believed must be met to ensure that CPRPs will be successful and sustainable. Group voting resulted in the selection of six needs that were considered to be consensus priorities for services and resources provided through CommuniRes: image parity for CPRPs; CPRP marketing materials; attractive postresidency employment opportunities; well-defined goals, objectives, and residency job descriptions; return on investment and sources of ongoing funding for the residency; and opportunities and mechanisms for communicating/networking with other residents and preceptors. The needs-based programmatic priorities defined by the advisory committee are now being implemented through a tripartite program consisting of live training seminars for CPRP preceptors and directors, an Internet site (www.communires.com), and a host of continuing support services available to affiliated CPRP sites. Future programmatic planning will increasingly involve CPRP preceptors, directors, and former residents to determine the ongoing needs of CPRPs.

  12. Sodium MRI using a density-adapted 3D radial acquisition technique.

    PubMed

    Nagel, Armin M; Laun, Frederik B; Weber, Marc-André; Matthies, Christian; Semmler, Wolfhard; Schad, Lothar R

    2009-12-01

    A density-adapted three-dimensional radial projection reconstruction pulse sequence is presented which provides a more efficient k-space sampling than conventional three-dimensional projection reconstruction sequences. The gradients of the density-adapted three-dimensional radial projection reconstruction pulse sequence are designed such that the averaged sampling density in each spherical shell of k-space is constant. Due to hardware restrictions, an inner sphere of k-space is sampled without density adaption. This approach benefits from both the straightforward handling of conventional three-dimensional projection reconstruction sequence trajectories and an enhanced signal-to-noise ratio (SNR) efficiency akin to the commonly used three-dimensional twisted projection imaging trajectories. Benefits for low SNR applications, when compared to conventional three-dimensional projection reconstruction sequences, are demonstrated with the example of sodium imaging. In simulations of the point-spread function, the SNR of small objects is increased by a factor 1.66 for the density-adapted three-dimensional radial projection reconstruction pulse sequence sequence. Using analytical and experimental phantoms, it is shown that the density-adapted three-dimensional radial projection reconstruction pulse sequence allows higher resolutions and is more robust in the presence of field inhomogeneities. High-quality in vivo images of the healthy human leg muscle and the healthy human brain are acquired. For equivalent scan times, the SNR is up to a factor of 1.8 higher and anatomic details are better resolved using density-adapted three-dimensional radial projection reconstruction pulse sequence. (c) 2009 Wiley-Liss, Inc.

  13. An Adaptive Pheromone Updation of the Ant-System using LMS Technique

    NASA Astrophysics Data System (ADS)

    Paul, Abhishek; Mukhopadhyay, Sumitra

    2010-10-01

    We propose a modified model of pheromone updation for Ant-System, entitled as Adaptive Ant System (AAS), using the properties of basic Adaptive Filters. Here, we have exploited the properties of Least Mean Square (LMS) algorithm for the pheromone updation to find out the best minimum tour for the Travelling Salesman Problem (TSP). TSP library has been used for the selection of benchmark problem and the proposed AAS determines the minimum tour length for the problems containing large number of cities. Our algorithm shows effective results and gives least tour length in most of the cases as compared to other existing approaches.

  14. An adaptive optimal control for smart structures based on the subspace tracking identification technique

    NASA Astrophysics Data System (ADS)

    Ripamonti, Francesco; Resta, Ferruccio; Borroni, Massimo; Cazzulani, Gabriele

    2014-04-01

    A new method for the real-time identification of mechanical system modal parameters is used in order to design different adaptive control logics aiming to reduce the vibrations in a carbon fiber plate smart structure. It is instrumented with three piezoelectric actuators, three accelerometers and three strain gauges. The real-time identification is based on a recursive subspace tracking algorithm whose outputs are elaborated by an ARMA model. A statistical approach is finally applied to choose the modal parameter correct values. These are given in input to model-based control logics such as a gain scheduling and an adaptive LQR control.

  15. Group Interpersonal Psychotherapy for depressed youth in IDP camps in Northern Uganda: adaptation and training.

    PubMed

    Verdeli, Helen; Clougherty, Kathleen; Onyango, Grace; Lewandowski, Eric; Speelman, Liesbeth; Betancourt, Teresa S; Neugebauer, Richard; Stein, Traci R; Bolton, Paul

    2008-07-01

    This article reviews the use of Interpersonal Psychotherapy (IPT) with depressed youth living in Internally Displaced Persons (IDP) camps in North Uganda. This youth has been exposed to severe losses and disruptions in relationships with caregivers, family, and community members; limited access to formal education; exposure to malnutrition and infections; and pressure to prematurely assume adult family roles. The process of adaptation to the content and training of IPT for these youth is presented and illustrated with case examples.

  16. Experience with A Direct Aspiration First Pass Technique (ADAPT) for Thrombectomy in Distal Cerebral Artery Occlusions Causing Acute Ischemic Stroke.

    PubMed

    Vargas, Jan; Spiotta, Alex M; Fargen, Kyle; Turner, Raymond D; Chaudry, Imran; Turk, Aquilla

    2017-03-01

    Thromboembolic occlusion of distal branches in anterior and posterior circulation may produce severe clinical deficits. A Direct Aspiration at first Pass Technique (ADAPT) is a simple, fast method for achieving good angiographic and clinical outcomes using large-bore catheters in large vessel occlusions. We present our results using ADAPT with distal cerebral artery occlusions. ADAPT was used to treat 35 patients (14 women, 21 men; average age 65.5 years ± 12.6) with acute ischemic stroke with thrombus in the distal middle cerebral artery, anterior cerebral artery, or posterior cerebral artery. Patients presented with a mean National Institutes of Health Stroke Scale score of 14.1 ± 6.9; 15 patients received intravenous tissue plasminogen activator. Mean time from onset to puncture was 7.1 hours ± 5.1. Of patients, 28 (80%) presented with isolated M2 segment occlusions, 1 (2.9%) presented with isolated A3 segment occlusion, and 6 (17.1%) presented with tandem occlusions. Mean time to recanalization was 35.7 minutes ± 26.4. A thrombolysis in cerebral infarction grade 2B or better was achieved in 34 patients (97.1%), with 15 achieving a thrombolysis in cerebral infarction 3. Aspiration alone was successful in 26 cases (77.1%), whereas 7 (20%) required additional techniques. A 90-day modified Rankin Scale score was available in 32 patients; 59.4% had a 90-day score of 0-2. No patients had a modified Rankin Scale score of 6. Acute distal anterior circulation thromboembolic occlusions may be treated safely with intraarterial thrombectomy. Prior studies have demonstrated the success of ADAPT in proximal large vessel occlusions. This series suggests that ADAPT is an effective, safe method for performing thrombectomy in distal branches of anterior and posterior circulation. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Adaptive Filter Techniques for Optical Beam Jitter Control and Target Tracking

    DTIC Science & Technology

    2008-12-01

    Analysis ......................................................51 5. Standard Deviation of Beam Position Error ...................................51 6...Organization of Analysis ...................................................................51 B. FEEDFORWARD ADAPTIVE FILTERS USING MULTIPLE...actuator (loud speaker or CFSM) before its effect reaches the error sensor. In ANC lingo , y(t) must first pass through the secondary plant dynamics of the

  18. Using a signal cancellation technique to assess adaptive directivity of hearing aids.

    PubMed

    Wu, Yu-Hsiang; Bentler, Ruth A

    2007-07-01

    The directivity of an adaptive directional microphone hearing aid (DMHA) cannot be assessed by the method that calls for presenting a "probe" signal from a single loudspeaker to the DMHA that moves to different angles. This method is invalid because the probe signal itself changes the polar pattern. This paper proposes a method for assessing the adaptive DMHA using a "jammer" signal, presented from a second loudspeaker rotating with the DMHA, that simulates a noise source and freezes the polar pattern. Measurement at each angle is obtained by two sequential recordings from the DMHA, one using an input of a probe and a jammer, and the other with an input of the same probe and a phase-inverted jammer. After canceling out the jammer, the remaining response to the probe signal can be used to assess the directivity. In this paper, the new method is evaluated by comparing responses from five adaptive DMHAs to different jammer intensities and locations. This method was shown to be an accurate and reliable way to assess the directivity of the adaptive DMHA in a high-intensity-jammer condition.

  19. Tools, techniques, organisation and culture of the CADD group at Sygnature Discovery

    NASA Astrophysics Data System (ADS)

    St-Gallay, Steve A.; Sambrook-Smith, Colin P.

    2016-10-01

    Computer-aided drug design encompasses a wide variety of tools and techniques, and can be implemented with a range of organisational structures and focus in different organisations. Here we outline the computational chemistry skills within Sygnature Discovery, along with the software and hardware at our disposal, and briefly discuss the methods that are not employed and why. The goal of the group is to provide support for design and analysis in order to improve the quality of compounds synthesised and reduce the timelines of drug discovery projects, and we reveal how this is achieved at Sygnature. Impact on medicinal chemistry is vital to demonstrating the value of computational chemistry, and we discuss the approaches taken to influence the list of compounds for synthesis, and how we recognise success. Finally we touch on some of the areas being developed within the team in order to provide further value to the projects and clients.

  20. Tools, techniques, organisation and culture of the CADD group at Sygnature Discovery

    NASA Astrophysics Data System (ADS)

    St-Gallay, Steve A.; Sambrook-Smith, Colin P.

    2017-03-01

    Computer-aided drug design encompasses a wide variety of tools and techniques, and can be implemented with a range of organisational structures and focus in different organisations. Here we outline the computational chemistry skills within Sygnature Discovery, along with the software and hardware at our disposal, and briefly discuss the methods that are not employed and why. The goal of the group is to provide support for design and analysis in order to improve the quality of compounds synthesised and reduce the timelines of drug discovery projects, and we reveal how this is achieved at Sygnature. Impact on medicinal chemistry is vital to demonstrating the value of computational chemistry, and we discuss the approaches taken to influence the list of compounds for synthesis, and how we recognise success. Finally we touch on some of the areas being developed within the team in order to provide further value to the projects and clients.

  1. Tools, techniques, organisation and culture of the CADD group at Sygnature Discovery.

    PubMed

    St-Gallay, Steve A; Sambrook-Smith, Colin P

    2016-10-31

    Computer-aided drug design encompasses a wide variety of tools and techniques, and can be implemented with a range of organisational structures and focus in different organisations. Here we outline the computational chemistry skills within Sygnature Discovery, along with the software and hardware at our disposal, and briefly discuss the methods that are not employed and why. The goal of the group is to provide support for design and analysis in order to improve the quality of compounds synthesised and reduce the timelines of drug discovery projects, and we reveal how this is achieved at Sygnature. Impact on medicinal chemistry is vital to demonstrating the value of computational chemistry, and we discuss the approaches taken to influence the list of compounds for synthesis, and how we recognise success. Finally we touch on some of the areas being developed within the team in order to provide further value to the projects and clients.

  2. Local versus global optimal sports techniques in a group of athletes.

    PubMed

    Huchez, Aurore; Haering, Diane; Holvoët, Patrice; Barbier, Franck; Begon, Mickael

    2015-01-01

    Various optimization algorithms have been used to achieve optimal control of sports movements. Nevertheless, no local or global optimization algorithm could be the most effective for solving all optimal control problems. This study aims at comparing local and global optimal solutions in a multistart gradient-based optimization by considering actual repetitive performances of a group of athletes performing a transition move on the uneven bars. Twenty-four trials by eight national-level female gymnasts were recorded using a motion capture system, and then multistart sequential quadratic programming optimizations were performed to obtain global optimal, local optimal and suboptimal solutions. The multistart approach combined with a gradient-based algorithm did not often find the local solution to be the best and proposed several other solutions including global optimal and suboptimal techniques. The qualitative change between actual and optimal techniques provided three directions for training: to increase hip flexion-abduction, to transfer leg and arm angular momentum to the trunk and to straighten hand path to the bar.

  3. [Operations research in group feeding programs: techniques for the identification and analysis of management problems].

    PubMed

    Montealegre, J; Fuentes, F; Mata, A; Cuevas, R

    1989-09-01

    The operations of the group feeding programs (PAG--"Programas de Alimentación a Grupos"--) can be viewed as a sequence of decisions and activities that according to their direction, order, relationship and dependency, will influence the quality and quantity of the service's delivery. While searching for the essential characteristics of a PAG: components, relationship, variables, pertinent parameters, restrictions, underlying criteria and objective functions, operations research can be useful for its analysis, the identification of its management problems, and to develop, evaluate and finally, implement solutions. Various operation research techniques are presented in this article, which are geared towards responding to those knowledge needs of the national technicians and program managers, in order to give a solid foundation to solutions for the management problems identified in a PAG. Failures of different quantitative models had been due, mainly, to the tendency to formulate models or investigate problems without users being prepared to implement the solutions. The techniques presented herein take into consideration the interaction between specialists and users.

  4. An Example of a Hakomi Technique Adapted for Functional Analytic Psychotherapy

    ERIC Educational Resources Information Center

    Collis, Peter

    2012-01-01

    Functional Analytic Psychotherapy (FAP) is a model of therapy that lends itself to integration with other therapy models. This paper aims to provide an example to assist others in assimilating techniques from other forms of therapy into FAP. A technique from the Hakomi Method is outlined and modified for FAP. As, on the whole, psychotherapy…

  5. A Cross-Cultural Adaptation of the Structured Life-Review Technique.

    ERIC Educational Resources Information Center

    Westcott, Nina A.

    1985-01-01

    The article uses a case example to show how the structured life-review technique was modified and used in a cross-cultural counseling situation. Specifically, the structured life-review technique was modified to meet the cultural requirements of indirectness, harmony, and acknowledgment of indebtedness and the view of the helper as teacher, valued…

  6. Visible light high-resolution imaging system for large aperture telescope by liquid crystal adaptive optics with phase diversity technique.

    PubMed

    Xu, Zihao; Yang, Chengliang; Zhang, Peiguang; Zhang, Xingyun; Cao, Zhaoliang; Mu, Quanquan; Sun, Qiang; Xuan, Li

    2017-08-30

    There are more than eight large aperture telescopes (larger than eight meters) equipped with adaptive optics system in the world until now. Due to the limitations such as the difficulties of increasing actuator number of deformable mirror, most of them work in the infrared waveband. A novel two-step high-resolution optical imaging approach is proposed by applying phase diversity (PD) technique to the open-loop liquid crystal adaptive optics system (LC AOS) for visible light high-resolution adaptive imaging. Considering the traditional PD is not suitable for LC AOS, the novel PD strategy is proposed which can reduce the wavefront estimating error caused by non-modulated light generated by liquid crystal spatial light modulator (LC SLM) and make the residual distortions after open-loop correction to be smaller. Moreover, the LC SLM can introduce any aberration which realizes the free selection of phase diversity. The estimating errors are greatly reduced in both simulations and experiments. The resolution of the reconstructed image is greatly improved on both subjective visual effect and the highest discernible space resolution. Such technique can be widely used in large aperture telescopes for astronomical observations such as terrestrial planets, quasars and also can be used in other applications related to wavefront correction.

  7. Internal adaptation and some physical properties of methacrylate-based denture base resins polymerized by different techniques.

    PubMed

    Ganzarolli, Solimar M; de Mello, José A Nunes; Shinkai, Rosemary S; Del Bel Cury, Altair A

    2007-07-01

    This study evaluated the internal adaptation, porosity, transverse and impact strength of three denture base polymers: (1) conventional heat-polymerized, (2) microwave-polymerized, and (3) injection-molded resins. Internal adaptation was measured by weighing a vinyl polysiloxane film reproducing the gap between the denture base and the metallic master model of an edentulous maxilla. The measurements were performed immediately after finishing and after 30-day storage in water. Porosity was evaluated by weighing each specimen in air and in water using an analytical scale balance. Transverse strength test (three-point bending test) was performed using a universal machine under axial load, at a crosshead speed of 5 mm/min. Impact strength test (Charpy's test) was performed with a 40 kJ/cm load. Data were analyzed by ANOVA and Tukey test (alpha = 0.05). Internal adaptation, porosity, transverse and impact strength varied according to the type of acrylic resin and the processing technique. The injection-molded resin showed better internal adaptation compared with the conventional heat-polymerized and the microwave-polymerized resins, particularly after 30 days, but there was no relevant improvement of porosity, transverse and impact strength. Copyright 2006 Wiley Periodicals, Inc.

  8. Assessment of Multi-Joint Coordination and Adaptation in Standing Balance: A Novel Device and System Identification Technique.

    PubMed

    Engelhart, Denise; Schouten, Alfred C; Aarts, Ronald G K M; van der Kooij, Herman

    2015-11-01

    The ankles and hips play an important role in maintaining standing balance and the coordination between joints adapts with task and conditions, like the disturbance magnitude and type, and changes with age. Assessment of multi-joint coordination requires the application of multiple continuous and independent disturbances and closed loop system identification techniques (CLSIT). This paper presents a novel device, the double inverted pendulum perturbator (DIPP), which can apply disturbing forces at the hip level and between the shoulder blades. In addition to the disturbances, the device can provide force fields to study adaptation of multi-joint coordination. The performance of the DIPP and a novel CLSIT was assessed by identifying a system with known mechanical properties and model simulations. A double inverted pendulum was successfully identified, while force fields were able to keep the pendulum upright. The estimated dynamics were similar as the theoretical derived dynamics. The DIPP has a sufficient bandwidth of 7 Hz to identify multi-joint coordination dynamics. An experiment with human subjects where a stabilizing force field was rendered at the hip (1500 N/m), showed that subjects adapt by lowering their control actions around the ankles. The stiffness from upper and lower segment motion to ankle torque dropped with 30% and 48%, respectively. Our methods allow to study (pathological) changes in multi-joint coordination as well as adaptive capacity to maintain standing balance.

  9. A simulation study of the validity and efficiency of design-adaptive allocation to two groups in the regression situation.

    PubMed

    Aickin, Mikel

    2009-05-29

    Dynamic allocation of participants to treatments in a clinical trial has been an alternative to randomization for nearly 35 years. Design-adaptive allocation is a particularly flexible kind of dynamic allocation. Every investigation of dynamic allocation methods has shown that they improve balance of prognostic factors across treatment groups, but there have been lingering doubts about their influence on the validity of statistical inferences. Here we report the results of a simulation study focused on this and similar issues. Overall, it is found that there are no statistical reasons, in the situations studied, to prefer randomization to design-adaptive allocation. Specifically, there is no evidence of bias, the number of participants wasted by randomization in small studies is not trivial, and when the aim is to place bounds on the prediction of population benefits, randomization is quite substantially less efficient than design-adaptive allocation. A new, adjusted permutation estimate of the standard deviation of the regression estimator under design-adaptive allocation is shown to be an unbiased estimate of the true sampling standard deviation, resolving a long-standing problem with dynamic allocations. These results are shown in situations with varying numbers of balancing factors, different treatment and covariate effects, different covariate distributions, and in the presence of a small number of outliers.

  10. A Simulation Study of the Validity and Efficiency of Design-Adaptive Allocation to Two Groups in the Regression Situation*

    PubMed Central

    Aickin, Mikel

    2009-01-01

    Dynamic allocation of participants to treatments in a clinical trial has been an alternative to randomization for nearly 35 years. Design-adaptive allocation is a particularly flexible kind of dynamic allocation. Every investigation of dynamic allocation methods has shown that they improve balance of prognostic factors across treatment groups, but there have been lingering doubts about their influence on the validity of statistical inferences. Here we report the results of a simulation study focused on this and similar issues. Overall, it is found that there are no statistical reasons, in the situations studied, to prefer randomization to design-adaptive allocation. Specifically, there is no evidence of bias, the number of participants wasted by randomization in small studies is not trivial, and when the aim is to place bounds on the prediction of population benefits, randomization is quite substantially less efficient than design-adaptive allocation. A new, adjusted permutation estimate of the standard deviation of the regression estimator under design-adaptive allocation is shown to be an unbiased estimate of the true sampling standard deviation, resolving a long-standing problem with dynamic allocations. These results are shown in situations with varying numbers of balancing factors, different treatment and covariate effects, different covariate distributions, and in the presence of a small number of outliers. PMID:20224630

  11. Novel growth techniques of group-IV based semiconductors on insulator for next-generation electronics

    NASA Astrophysics Data System (ADS)

    Miyao, Masanobu; Sadoh, Taizoh

    2017-05-01

    Recent progress in the crystal growth of group-IV-based semiconductor-on-insulators is reviewed from physical and technological viewpoints. Liquid-phase growth based on SiGe-mixing-triggered rapid-melting growth enables formation of hybrid (100) (110) (111)-orientation Ge-on-insulator (GOI) structures, which show defect-free GOI with very high carrier mobility (˜1040 cm2 V-1 s-1). Additionally, SiGe mixed-crystals with laterally uniform composition were obtained by eliminating segregation phenomena during the melt-back process. Low-temperature solid-phase growth has been explored by combining this process with ion-beam irradiation, additional doping of group-IV elements, metal induced lateral crystallization with/without electric field, and metal-induced layer exchange crystallization. These efforts have enabled crystal growth on insulators below 400 °C, achieving high carrier mobility (160-320 cm2 V-1 s-1). Moreover, orientation-controlled SiGe and Ge films on insulators have been obtained below the softening temperatures of conventional plastic films (˜300 °C). Detailed characterization provides an understanding of physical phenomena behind these crystal growth techniques. Applying these methods when fabricating next-generation electronics is also discussed.

  12. Validity of the Addiction Severity Index (adapted version) in a Costa Rican population group.

    PubMed

    Sandí Esquivel, L E; Avila Corrales, K

    1990-01-01

    Until recently, no adapted and validated instrument was available for assessing the alcohol and drug problems of individuals in Costa Rica. This article reports the results of a study performed by Costa Rica's Institute on Alcoholism and Drug Dependence in order to test an adapted version of one such instrument, the Addiction Severity Index (ASI), in a Costa Rican setting. The instrument was used to interview 100 male subjects 18 to 64 years old (51 with diagnosed alcohol or drug problems and 49 controls). In general, the subjects with previously diagnosed alcohol or drug problems were assigned substantially higher scores. More specifically, statistical analysis indicated highly significant correlations (p less than 0.001) between the type of subject (test subject or control) and the likelihood that noteworthy problems would be found in the areas of alcohol use, family/social relations, work/finances, and psychological status. Overall, the study demonstrated that the instrument was capable of distinguishing between the affected and unaffected populations, and also of gauging the severity of the problems involved and the patients' treatment needs.

  13. Evolutionary architecture of the infant-adapted group of Bifidobacterium species associated with the probiotic function.

    PubMed

    Kwak, Min-Jung; Kwon, Soon-Kyeong; Yoon, Jae-Kyung; Song, Ju Yeon; Seo, Jae-Gu; Chung, Myung Jun; Kim, Jihyun F

    2016-10-01

    Bifidobacteria, often associated with the gastrointestinal tract of animals, are well known for their roles as probiotics. Among the dozens of Bifidobacterium species, Bifidobacterium bifidum, B. breve, and B. longum are the ones most frequently isolated from the feces of infants and known to help the digestion of human milk oligosaccharides. To investigate the correlation between the metabolic properties of bifidobacteria and their phylogeny, we performed a phylogenomic analysis based on 452 core genes of forty-four completely sequenced Bifidobacterium species. Results show that a major evolutionary event leading to the clade of the infant-adapted species is linked to carbohydrate metabolism, but it is not the only factor responsible for the adaptation of bifidobacteria to the gut. The genome of B. longum subsp. infantis, a typical bifidobacterium in the gut of breast-fed infants, encodes proteins associated with several kinds of species-specific metabolic pathways, including urea metabolism and biosynthesis of riboflavin and lantibiotics. Our results demonstrate that these metabolic features, which are associated with the probiotic function of bifidobacteria, are species-specific and highly correlate with their phylogeny. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Anatomical and ultrastructural adaptations of seagrass leaves: an evaluation of the southern Atlantic groups.

    PubMed

    Ferreira, Chirle; Horta, Paulo A; Almeida, Gabriela M; Zitta, Carmen S; de M Oliveira, Eliana; Gueye, Marietou B Y B; Rodrigues, Ana C

    2015-01-01

    Seagrasses, which form an integral part of the worldwide coastal habitat, are considered highly relevant from an ecological point of view. Due to the scarcity of anatomical information, the present study analyzed the morphoanatomy, histochemistry, and ultrastructure of Halophila decipiens, Halodule wrightii, and Ruppia maritima leaves, discussing their adaptations to the marine environments observed throughout the southwestern tropical and subtropical Atlantic coast. The leaves of these three species feature a uniseriate epidermis with the presence of chloroplasts in large quantities and absence of stomata. The vascular system consists of a central vascular bundle with sieve tube elements of the phloem and protoxylem lacunae, as well as small vascular bundles near the leaf margins. The leaves of H. decipiens possess trichomes, but no mesophyll in the leaf margins. The mesophyll of H. wrightii and R. maritima is homogeneous with chlorenchyma cells and air lacunae scattered throughout the leaf. The histochemistry analysis revealed the absence of amyloplasts and the presence of proteins in the outer periclinal walls of ordinary epidermal cells of the three species. It was also possible to detect the presence of idioblasts containing phenolic compounds in H. decipiens and R. maritima. The ultrastructural analysis of the three species revealed many elliptical chloroplasts, with organized thylakoids, expansion of the epidermal cell wall into the cytoplasm, and a thin cuticle. Hydropoten were also observed in the three specimens. The results show that the species analyzed have important adaptations which enable their survival in the marine environment.

  15. Robust adaptive synchronization of Rossler and Chen chaotic systems via slide technique

    NASA Astrophysics Data System (ADS)

    Li, Zhi; Shi, Songjiao

    2003-05-01

    This Letter considers the robust adaptive synchronization problem of Rossler and Chen chaotic systems with different time-varying unknown parameters. When system's unknown parameters vary in bound intervals and the bounds of intervals are unknown, a robust adaptive controller is designed. In order to increase the robustness of the closed loop systems, the key idea is that a sliding mode type of controller is employed. Besides, instead of the estimate values of systems' unknown parameters being taken as updating object, a new updating object is introduced in constructing controller. The proposed controller can make the states of Rossler and Chen chaotic systems globally asymptotically robustly synchronized. Simulation results are given to show the effectiveness of the proposed method.

  16. Adaptive mesh refinement techniques for the immersed interface method applied to flow problems

    PubMed Central

    Li, Zhilin; Song, Peng

    2013-01-01

    In this paper, we develop an adaptive mesh refinement strategy of the Immersed Interface Method for flow problems with a moving interface. The work is built on the AMR method developed for two-dimensional elliptic interface problems in the paper [12] (CiCP, 12(2012), 515–527). The interface is captured by the zero level set of a Lipschitz continuous function φ(x, y, t). Our adaptive mesh refinement is built within a small band of |φ(x, y, t)| ≤ δ with finer Cartesian meshes. The AMR-IIM is validated for Stokes and Navier-Stokes equations with exact solutions, moving interfaces driven by the surface tension, and classical bubble deformation problems. A new simple area preserving strategy is also proposed in this paper for the level set method. PMID:23794763

  17. Technical note: a technique for ear vein catheterization in group-housed sows.

    PubMed

    Phillips, C E; Li, Y Z; Johnston, L J; Goplen, A E; Shurson, G C

    2012-02-01

    No methods have been published for repeated blood sampling via an ear vein in group-housed sows. Therefore, the objective of this study was to develop a minimally invasive technique for the insertion of an ear vein catheter for repeated blood sampling in group-housed peripartum sows while minimizing any impact on production performance. Thirty-three multiparous pregnant sows were used including 18 catheterized sows and 15 control sows. In a group-farrowing barn, sows (8/room) shared a communal area and farrowed in individual, free-access pens. Treatment sows were anesthetized, and 1 ear was prepared aseptically 2 to 4 d before their expected farrowing date. A sterile needle was inserted into the largest and straightest portion of the vein, and the catheter, which was medical-grade microbore tubing, was inserted through the needle at least 24 cm. The needle was withdrawn, and the catheter was fixed into position and sutured to the ear. A blunt-end probe point cannula was glued onto the distal end of the catheter, and an adaptor injection cap with male Luer lock was placed on the end. The catheter was coiled and placed in a protective purse, which was cemented directly to the skin on the back of the shoulders. The catheter was flushed with heparinized saline to ensure patency. Once sows were able to stand, an elastic bandage was wrapped around the neck and upper body of the sow to hold the protective purse and exposed catheter in position. Blood samples were collected every 24 h, and catheters were flushed with heparinized saline after each collection. Fourteen of the 18 insertions were successful, and 11 of those remained functional for 4 d or more. Differences were not observed in reproductive performance between catheterized and noncatheterized sows.

  18. Two Group Development Patterns of Virtual Learning Teams: Linear Progression and Adaptive Progression

    ERIC Educational Resources Information Center

    Yoon, Seung Won

    2006-01-01

    This study examined member behaviors, distribution of performed behaviors, and development-shaping forces in order to identify group development patterns of virtual learning teams. Participants of this study were 7 newly formed virtual learning teams working on a final group project in a 12-week online graduate-level course. Examining the group…

  19. Two Group Development Patterns of Virtual Learning Teams: Linear Progression and Adaptive Progression

    ERIC Educational Resources Information Center

    Yoon, Seung Won

    2006-01-01

    This study examined member behaviors, distribution of performed behaviors, and development-shaping forces in order to identify group development patterns of virtual learning teams. Participants of this study were 7 newly formed virtual learning teams working on a final group project in a 12-week online graduate-level course. Examining the group…

  20. Mainland Chinese Students' Group Work Adaptation in a UK Business School

    ERIC Educational Resources Information Center

    Wang, Yi

    2012-01-01

    Built from data collected through three-phase in-depth interviews, this study explores from cultural and social perspectives why Chinese students may initially be termed silent participants when they first commence group work with western students; and then examines the impact of cultural interaction through group work on their adjustment.…

  1. Dynamic Adaptive Binning: An Improved Quantification Technique for NMR Spectroscopic Data

    DTIC Science & Technology

    2010-01-01

    adaptive intelligent binning, which recursively identifies bin edges in existing bins (De Meyer et al. 2008). Another dynamic binning method is...43. Cancino-De-Greiff, H. F., Ramos-Garcia, R., & Lorenzo -Ginori, J. V. (2002). Signal de-noising in magnetic resonance spectroscopy using wavelet...for metabolomics data using the undecimated wavelet transform. Chemometrics and Intelligent Laboratory Systems, 85, 144–154. De Meyer , T., Sinnaeve, D

  2. Adaption of egg and larvae sampling techniques for lake sturgeon and broadcast spawning fishes in a deep river

    USGS Publications Warehouse

    Roseman, Edward F.; Kennedy, Gregory W.; Craig, Jaquelyn; Boase, James; Soper, Karen

    2011-01-01

    In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy-less method for sampling fish eggs and spawning activity using egg mats deployed on the river bottom. The buoy-less method allowed us to fish gear in areas frequented by boaters and recreational anglers, thus eliminating surface obstructions that interfered with recreational and boating activities. The buoy-less method also reduced gear loss due to drift when masses of floating aquatic vegetation would accumulate on buoys and lines, increasing the drag on the gear and pulling it downstream. Second, we adapted a D-frame drift net system formerly employed in shallow streams to assess larval lake sturgeon dispersal for use in the deeper (>8 m) Detroit River using an anchor and buoy system.

  3. Comparison of antibody titers using conventional tube technique versus column agglutination technique in ABO blood group incompatible renal transplant.

    PubMed

    Bhangale, Amit; Pathak, Amardeep; Pawar, Smita; Jeloka, Tarun

    2017-01-01

    Measurement of alloantibody titer to a red cell antigen (ABO titers) is an integral part of management of ABO incompatible kidney transplants (ABOiKT). There are different methods of titer estimation. Alloantibody detection by tube titration and Gel agglutination columns are accepted methodologies. It is essential to find the difference in titers between the two methods so as to set the 'cut-off' titer accordingly, depending upon the method used. We did a prospective observational study to compare and correlate the ABO titers using these two different techniques - conventional tube technique (CTT) and the newer column agglutination technique (CAT). A total of 67 samples were processed in parallel for anti-A/B antibodies by both tube dilution and column agglutination methods. The mean titer by conventional tube method was 38.5 + 96.6 and by the column agglutination test was 96.4 + 225. The samples correlated well with Spearman rho correlation coefficient of 0.94 (P = 0.01). The column agglutination method for anti A/B titer estimation in an ABO incompatible kidney transplant is more sensitive, with the column agglutination results being approximately two and half fold higher (one more dilution) than that of tube method.

  4. A Fast, Efficient Domain Adaptation Technique for Cross-Domain Electroencephalography(EEG)-Based Emotion Recognition.

    PubMed

    Chai, Xin; Wang, Qisong; Zhao, Yongping; Li, Yongqiang; Liu, Dan; Liu, Xin; Bai, Ou

    2017-05-03

    Electroencephalography (EEG)-based emotion recognition is an important element in psychiatric health diagnosis for patients. However, the underlying EEG sensor signals are always non-stationary if they are sampled from different experimental sessions or subjects. This results in the deterioration of the classification performance. Domain adaptation methods offer an effective way to reduce the discrepancy of marginal distribution. However, for EEG sensor signals, both marginal and conditional distributions may be mismatched. In addition, the existing domain adaptation strategies always require a high level of additional computation. To address this problem, a novel strategy named adaptive subspace feature matching (ASFM) is proposed in this paper in order to integrate both the marginal and conditional distributions within a unified framework (without any labeled samples from target subjects). Specifically, we develop a linear transformation function which matches the marginal distributions of the source and target subspaces without a regularization term. This significantly decreases the time complexity of our domain adaptation procedure. As a result, both marginal and conditional distribution discrepancies between the source domain and unlabeled target domain can be reduced, and logistic regression (LR) can be applied to the new source domain in order to train a classifier for use in the target domain, since the aligned source domain follows a distribution which is similar to that of the target domain. We compare our ASFM method with six typical approaches using a public EEG dataset with three affective states: positive, neutral, and negative. Both offline and online evaluations were performed. The subject-to-subject offline experimental results demonstrate that our component achieves a mean accuracy and standard deviation of 80.46% and 6.84%, respectively, as compared with a state-of-the-art method, the subspace alignment auto-encoder (SAAE), which achieves values

  5. Adapting Minority Group Threat to Examine the Social Control of Sexual Orientation Bias.

    PubMed

    Stacey, Michele

    2016-02-24

    Blalock proposed that the threat of a minority group toward a majority in sheer size, economic competition, or power will result in an increase in discrimination toward that group. His original formulation of this theory of minority group threat, and its subsequent extensions, has focused almost exclusively on racial minority-majority relationships; however, Blalock asserted that his theory would apply to any minority-majority group relationship. Extensions to religious groups have shown this is likely the case. The current analysis assesses a further extension of minority group threat by reframing the arguments of the theory and adding two additional sources of threat to examine sexual orientation bias. Data from the Uniform Crime Reports Hate Crime Statistics program are used to assess whether the minority group threat hypotheses explain the reporting of sexual orientation bias crimes. The findings indicate that the original formulation of Blalock's theory does not suffice to explain the reporting of anti-Lesbian, Gay, and Bisexual bias crime, but the proposed extensions may explain some of this variation.

  6. Three-dimensional shape measurement technique for shiny surfaces by adaptive pixel-wise projection intensity adjustment

    NASA Astrophysics Data System (ADS)

    Lin, Hui; Gao, Jian; Mei, Qing; Zhang, Guanjin; He, Yunbo; Chen, Xin

    2017-04-01

    Conventional methods based on analyses of the absolute gray levels of pixels in fringe pattern images are affected by the problems of image saturation, interreflection, and high sensitivity to noise when obtaining three-dimensional (3D) shape measurements of shiny surfaces. This study presents a robust, adaptive, and fast 3D shape measurement technique, which adaptively adjusts the pixel-wise intensity of the projected patterns, thus it avoids image saturation and has a high signal to noise ratio (SNR) during 3D shape measurement for shiny surfaces. Compared with previous time-consuming methods using multiple exposures and the projection of fringe patterns with multiple intensities, where a large number of fringe pattern images need to be captured, the proposed technique needs to capture far fewer pattern images for measurement. In addition, it can greatly reduce the time costs to obtain the optimal projection intensities by the fusion of uniform gray level patterns and coordinates mapping. Our experimental results demonstrate that the proposed technique can achieve highly accurate and efficient 3D shape measurement for shiny surfaces.

  7. Using the Leaderless Group Discussion Technique for the Selection of Residence Hall Counselors

    ERIC Educational Resources Information Center

    Banta, Trudy W.; McCormick, Jane E.

    1969-01-01

    Describes successful effort to involve head residents in selection responsibilities. Discusses use of Record of Previous Leadership Experience, behavior ratings adapted from Interview and LGD Rating Scale (T. W. Banta) recommendation from head resident as selection criteria. (CJ)

  8. Scrap Cans Assayed in 55-Gallon Drums by Adapted Q2 Technique

    SciTech Connect

    Salaymeh, S.R.

    2001-07-24

    This report describes an alternate assay technique developed to perform batch nondestructive assay (NDA) of ten scrap cans at a time. This report also discusses and compares the results of the one batch of ten scrap cans by assaying them individually at the 324-M assay station with the alternate assay technique developed to perform batch NDA of ten scrap cans at a time using the Q2.

  9. Adaptive actuator failure compensation control based on MMST grouping for a class of MIMO nonlinear systems with guaranteed transient performance

    NASA Astrophysics Data System (ADS)

    Zhang, Shao-Jie; Qiu, Xiang-Wei; Jiang, Bin; Liu, Chun-Sheng

    2015-03-01

    This paper presents a new adaptive compensation control approach for a class of multi-input multi-output (MIMO) nonlinear systems with actuator failures. In order to enlarge the set of compensable actuator failures, an actuators grouping scheme based on multiple model switching and tuning (MMST) is proposed for the nonlinear MIMO minimum-phase systems with multiple actuator failures. Then, an adaptive compensation scheme based on prescribed performance bound (PPB) which characterises the convergence rate and maximum overshoot of the tracking error is designed for the systems to ensure closed-loop signal boundedness and asymptotic output tracking despite unknown actuator failures. Simulation results are given to show the effectiveness of the control design.

  10. A Phase I/II adaptive design for heterogeneous groups with application to a stereotactic body radiation therapy trial.

    PubMed

    Wages, Nolan A; Read, Paul W; Petroni, Gina R

    2015-01-01

    Dose-finding studies that aim to evaluate the safety of single agents are becoming less common, and advances in clinical research have complicated the paradigm of dose finding in oncology. A class of more complex problems, such as targeted agents, combination therapies and stratification of patients by clinical or genetic characteristics, has created the need to adapt early-phase trial design to the specific type of drug being investigated and the corresponding endpoints. In this article, we describe the implementation of an adaptive design based on a continual reassessment method for heterogeneous groups, modified to coincide with the objectives of a Phase I/II trial of stereotactic body radiation therapy in patients with painful osseous metastatic disease. Operating characteristics of the Institutional Review Board approved design are demonstrated under various possible true scenarios via simulation studies. Copyright © 2015 John Wiley & Sons, Ltd.

  11. Resolving M-Dwarf Binaries In Young Moving Groups With Magellan Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Shan, Yutong; Yee, Jennifer; Bowler, Brendan

    2016-07-01

    YMGs are benchmarks for the transition of stellar populations from their birth clusters to the field. We present data and analysis from our Magellan Adaptive Optics (MagAO) campaign to image more than 100 M-dwarf members of several YMGs in the southern sky, revealing 30 previously unresolved visual stellar companions at separations of 3 — 500 AU. Our study provides multiplicity statistics for young M-dwarfs in this intermediate regime of orbital distance. We combine our results with the SACY survey (Elliott et al. 2015), whose focus is on YMG systems with earlier type primaries, to provide an updated measurement of multiplicity as a function of stellar mass with significantly more statistical power at lower masses. Additionally, the tighter systems in our sample provide the opportunity for future monitoring and dynamical mass inference.

  12. Adapting health promotion interventions to meet the needs of ethnic minority groups: mixed-methods evidence synthesis.

    PubMed

    Liu, Jj; Davidson, E; Bhopal, Rs; White, M; Johnson, Mrd; Netto, G; Deverill, M; Sheikh, A

    2012-01-01

    There is now a considerable body of evidence revealing that a number of ethnic minority groups in the UK and other economically developed countries experience disproportionate levels of morbidity and mortality compared with the majority white European-origin population. Across these countries, health-promoting approaches are increasingly viewed as the long-term strategies most likely to prove clinically effective and cost-effective for preventing disease and improving health outcomes in those with established disease. To identify, appraise and interpret research on the approaches employed to maximise the cross-cultural appropriateness and effectiveness of health promotion interventions for smoking cessation, increasing physical activity and improving healthy eating for African-, Chinese- and South Asian-origin populations. Two national conferences; seven databases of UK guidelines and international systematic reviews of health promotion interventions aimed at the general population, including the Clinical Evidence, National Institute for Health and Clinical Excellence and Scottish Intercollegiate Guidelines Network databases (1950-2009); 11 databases of research on adapted health promotion interventions for ethnic minority populations, including BIOSIS, EMBASE and MEDLINE (1950-2009); and in-depth qualitative interviews with a purposive sample of researchers and health promoters. Theoretically based, mixed-methods, phased programme of research that involved user engagement, systematic reviews and qualitative interviews, which were integrated through a realist synthesis. Following a launch conference, two reviewers independently identified and extracted data from guidelines and systematic reviews on the effectiveness of interventions for the general population and any guidance offered in relation to how to interpret this evidence for ethnic minority populations. Data were thematically analysed. Reviewers then independently identified and critically appraised studies

  13. Adaptive Grouping Cloud Model Shuffled Frog Leaping Algorithm for Solving Continuous Optimization Problems

    PubMed Central

    Liu, Haorui; Yi, Fengyan; Yang, Heli

    2016-01-01

    The shuffled frog leaping algorithm (SFLA) easily falls into local optimum when it solves multioptimum function optimization problem, which impacts the accuracy and convergence speed. Therefore this paper presents grouped SFLA for solving continuous optimization problems combined with the excellent characteristics of cloud model transformation between qualitative and quantitative research. The algorithm divides the definition domain into several groups and gives each group a set of frogs. Frogs of each region search in their memeplex, and in the search process the algorithm uses the “elite strategy” to update the location information of existing elite frogs through cloud model algorithm. This method narrows the searching space and it can effectively improve the situation of a local optimum; thus convergence speed and accuracy can be significantly improved. The results of computer simulation confirm this conclusion. PMID:26819584

  14. Adaptive Grouping Cloud Model Shuffled Frog Leaping Algorithm for Solving Continuous Optimization Problems.

    PubMed

    Liu, Haorui; Yi, Fengyan; Yang, Heli

    2016-01-01

    The shuffled frog leaping algorithm (SFLA) easily falls into local optimum when it solves multioptimum function optimization problem, which impacts the accuracy and convergence speed. Therefore this paper presents grouped SFLA for solving continuous optimization problems combined with the excellent characteristics of cloud model transformation between qualitative and quantitative research. The algorithm divides the definition domain into several groups and gives each group a set of frogs. Frogs of each region search in their memeplex, and in the search process the algorithm uses the "elite strategy" to update the location information of existing elite frogs through cloud model algorithm. This method narrows the searching space and it can effectively improve the situation of a local optimum; thus convergence speed and accuracy can be significantly improved. The results of computer simulation confirm this conclusion.

  15. Occupational therapy with people with depression: using nominal group technique to collate clinician opinion.

    PubMed

    Hitch, Danielle; Taylor, Michelle; Pepin, Genevieve

    2015-05-01

    This aim of this study was to obtain a consensus from clinicians regarding occupational therapy for people with depression, for the assessments and practices they use that are not currently supported by research evidence directly related to functional performance. The study also aimed to discover how many of these assessments and practices were currently supported by research evidence. Following a previously reported systematic review of assessments and practices used in occupational therapy for people with depression, a modified nominal group technique was used to discover which assessments and practices occupational therapists currently utilize. Three online surveys gathered initial data on therapeutic options (survey 1), which were then ranked (survey 2) and re-ranked (survey 3) to gain the final consensus. Twelve therapists completed the first survey, whilst 10 clinicians completed both the second and third surveys. Only 30% of the assessments and practices identified by the clinicians were supported by research evidence. A consensus was obtained on a total of 35 other assessments and interventions. These included both occupational-therapy-specific and generic assessments and interventions. Principle conclusion. Very few of the assessments and interventions identified were supported by research evidence directly related to functional performance. While a large number of options were generated, the majority of these were not occupational therapy specific.

  16. Renormalization group theory outperforms other approaches in statistical comparison between upscaling techniques for porous media

    NASA Astrophysics Data System (ADS)

    Hanasoge, Shravan; Agarwal, Umang; Tandon, Kunj; Koelman, J. M. Vianney A.

    2017-09-01

    Determining the pressure differential required to achieve a desired flow rate in a porous medium requires solving Darcy's law, a Laplace-like equation, with a spatially varying tensor permeability. In various scenarios, the permeability coefficient is sampled at high spatial resolution, which makes solving Darcy's equation numerically prohibitively expensive. As a consequence, much effort has gone into creating upscaled or low-resolution effective models of the coefficient while ensuring that the estimated flow rate is well reproduced, bringing to the fore the classic tradeoff between computational cost and numerical accuracy. Here we perform a statistical study to characterize the relative success of upscaling methods on a large sample of permeability coefficients that are above the percolation threshold. We introduce a technique based on mode-elimination renormalization group theory (MG) to build coarse-scale permeability coefficients. Comparing the results with coefficients upscaled using other methods, we find that MG is consistently more accurate, particularly due to its ability to address the tensorial nature of the coefficients. MG places a low computational demand, in the manner in which we have implemented it, and accurate flow-rate estimates are obtained when using MG-upscaled permeabilities that approach or are beyond the percolation threshold.

  17. Adaptation of the staphylococcal coagglutination technique for detection of heat-labile enterotoxin of Escherichia coli.

    PubMed Central

    Brill, B M; Wasilauskas, B L; Richardson, S H

    1979-01-01

    Protein A-containing staphylococci coated with specific antiserum were tested for heat-labile enterotoxin of Escherichia coli. The immunological cross-reactivity of E. coli heat-labile enterotoxin with Vibrio cholerae toxin (choleragen) was the basis for sensitizing stabilized suspensions of the Cowan I strain of Staphylococcus aureus with anticholeragen. Unconcentrated culture supernatant fluid containing E. coli heat-labile enterotoxin produced macroscopic agglutination when mixed with sensitized staphylococci in capillary tubes. A total of 15 toxigenic and 61 nontoxigenic isolates were tested by the staphylococcal coagglutination technique in a coded fashion and found to be in agreement with previous results of the Chinese hamster ovary cell assay and the passive immune hemolysis test. The staphylococcal coagglutination technique is simple, relatively inexpensive to perform, and requires the immunoglobulin fraction of anticholeragen as the only specific reagent. The staphylococcal coagglutination technique appears to have potential for routine use in diagnostic microbiology laboratories. Images PMID:372214

  18. Continuous digital ECG analysis over accurate R-peak detection using adaptive wavelet technique.

    PubMed

    Gopalakrishnan Nair, T R; Geetha, A P; Asharani, M

    2013-10-01

    Worldwide, health care segment is under a severe challenge to achieve more accurate and intelligent biomedical systems in order to assist healthcare professionals with more accurate and consistent data as well as reliability. The role of ECG in healthcare is one of the paramount importances and it has got a multitude of abnormal relations and anomalies which characterizes intricate cardiovascular performance image. Until the recent past, ECG instruments and analysis played the role of providing the PQRST signal as raw observational output either on paper or on a console or in a file having many diagnostic clues embedded in the signal left to the expert cardiologist to look out for characteristic intervals and to detect the cardiovascular abnormality. Methods and practises are required more and more, to automate this process of cardiac expertise using knowledge engineering and an intelligent systems approach. This paper presents one of the challenging R-peak detections to classify diagnosis and estimate cardio disorders in a fully automated signal processing sequence. This study used an adaptive wavelet approach to generate an appropriate wavelet for R-signal identification under noise, baseband wandering and temporal variations of R-positions. This study designed an adaptive wavelet and successfully detected R- peak variations under various ECG signal conditions. The result and analysis of this method and the ways to use it for further purposes are presented here.

  19. The adaptation of GDL motion recognition system to sport and rehabilitation techniques analysis.

    PubMed

    Hachaj, Tomasz; Ogiela, Marek R

    2016-06-01

    The main novelty of this paper is presenting the adaptation of Gesture Description Language (GDL) methodology to sport and rehabilitation data analysis and classification. In this paper we showed that Lua language can be successfully used for adaptation of the GDL classifier to those tasks. The newly applied scripting language allows easily extension and integration of classifier with other software technologies and applications. The obtained execution speed allows using the methodology in the real-time motion capture data processing where capturing frequency differs from 100 Hz to even 500 Hz depending on number of features or classes to be calculated and recognized. Due to this fact the proposed methodology can be used to the high-end motion capture system. We anticipate that using novel, efficient and effective method will highly help both sport trainers and physiotherapist in they practice. The proposed approach can be directly applied to motion capture data kinematics analysis (evaluation of motion without regard to the forces that cause that motion). The ability to apply pattern recognition methods for GDL description can be utilized in virtual reality environment and used for sport training or rehabilitation treatment.

  20. Validation of a Bayesian Adaptive Estimation Technique in the Stop-Signal Task

    PubMed Central

    Livesey, Evan J.; Livesey, David J.

    2016-01-01

    The Stop Signal Task (SST), a commonly used measure of response inhibition, uses standard psychophysical methods to gain an estimate of the time needed to withhold a prepotent response. Under some circumstances, conventional forms of the SST are impractical to use because of the large number of trials necessary to gain a reliable estimate of the speed of inhibition. Here we applied to the SST an adaptive method for estimating psychometric parameters that can find reliable threshold estimates over a relatively small number of trials. The Ψ adaptive staircase, which uses a Bayesian algorithm to find the most likely parameters of a psychophysical function, was used to estimate the critical stop signal delay at which the probability of successful response inhibition equals 0.5. Using computational modeling and adult participants, estimates of stop signal reaction time (SSRT) based on the Ψ staircase were compared to estimates using the method of constant stimuli and a standard staircase method of adjustment. Results demonstrate that a reliable estimate of SSRT can be gained very quickly (20–30 stop trials), making the method very useful for testing populations that cannot maintain concentration for long periods or for rapidly obtaining multiple SSRT estimates from healthy adult participants. PMID:27880815

  1. Accurate Adaptive Level Set Method and Sharpening Technique for Three Dimensional Deforming Interfaces

    NASA Technical Reports Server (NTRS)

    Kim, Hyoungin; Liou, Meng-Sing

    2011-01-01

    In this paper, we demonstrate improved accuracy of the level set method for resolving deforming interfaces by proposing two key elements: (1) accurate level set solutions on adapted Cartesian grids by judiciously choosing interpolation polynomials in regions of different grid levels and (2) enhanced reinitialization by an interface sharpening procedure. The level set equation is solved using a fifth order WENO scheme or a second order central differencing scheme depending on availability of uniform stencils at each grid point. Grid adaptation criteria are determined so that the Hamiltonian functions at nodes adjacent to interfaces are always calculated by the fifth order WENO scheme. This selective usage between the fifth order WENO and second order central differencing schemes is confirmed to give more accurate results compared to those in literature for standard test problems. In order to further improve accuracy especially near thin filaments, we suggest an artificial sharpening method, which is in a similar form with the conventional re-initialization method but utilizes sign of curvature instead of sign of the level set function. Consequently, volume loss due to numerical dissipation on thin filaments is remarkably reduced for the test problems

  2. Adaptive threshold-based spatio-temporal filtering techniques for detection of small targets

    NASA Astrophysics Data System (ADS)

    Ronda, Venkateswarlu; New, Wei L.; Tan, M. J.; Er, Meng H.

    2000-07-01

    There are several methods reported in the literature for detecting dim targets against slowly moving clutter. However, each method has its own advantages and disadvantages. The challenge lies in reducing the false alarm rate to an acceptable level. Choosing a threshold for achieving constant false alarm rate is always a tricky problem. Too less a threshold may ensure detection of target pixels. But this will result in with too many false targets, which limit the performance of the post- processor to trace out target paths. Too high threshold results in fewer false alarms but the targets also may miss out, creating a problem in establishing track record of targets. These contradicting issues demand a via-media solution to improve the overall concept of CFAR for the detection of dim point-targets in the presence of the evolving clouds and heavy background clutter. The adaptive threshold is based on random and correlated noises of the incoming image sequence. The incoming frames of data are processed by adaptive threshold and accumulated recursively. The post-processor with built-in flexibility checks for validity of target paths. This paper presents an improvement over our paper presented at SPIE, Denver duing July 1999. The algorithm has been tested with the available database and the results are very promising.

  3. An adaptive threshold based image processing technique for improved glaucoma detection and classification.

    PubMed

    Issac, Ashish; Partha Sarathi, M; Dutta, Malay Kishore

    2015-11-01

    Glaucoma is an optic neuropathy which is one of the main causes of permanent blindness worldwide. This paper presents an automatic image processing based method for detection of glaucoma from the digital fundus images. In this proposed work, the discriminatory parameters of glaucoma infection, such as cup to disc ratio (CDR), neuro retinal rim (NRR) area and blood vessels in different regions of the optic disc has been used as features and fed as inputs to learning algorithms for glaucoma diagnosis. These features which have discriminatory changes with the occurrence of glaucoma are strategically used for training the classifiers to improve the accuracy of identification. The segmentation of optic disc and cup based on adaptive threshold of the pixel intensities lying in the optic nerve head region. Unlike existing methods the proposed algorithm is based on an adaptive threshold that uses local features from the fundus image for segmentation of optic cup and optic disc making it invariant to the quality of the image and noise content which may find wider acceptability. The experimental results indicate that such features are more significant in comparison to the statistical or textural features as considered in existing works. The proposed work achieves an accuracy of 94.11% with a sensitivity of 100%. A comparison of the proposed work with the existing methods indicates that the proposed approach has improved accuracy of classification glaucoma from a digital fundus which may be considered clinically significant.

  4. Direct adaptive performance optimization of subsonic transports: A periodic perturbation technique

    NASA Technical Reports Server (NTRS)

    Espana, Martin D.; Gilyard, Glenn

    1995-01-01

    Aircraft performance can be optimized at the flight condition by using available redundancy among actuators. Effective use of this potential allows improved performance beyond limits imposed by design compromises. Optimization based on nominal models does not result in the best performance of the actual aircraft at the actual flight condition. An adaptive algorithm for optimizing performance parameters, such as speed or fuel flow, in flight based exclusively on flight data is proposed. The algorithm is inherently insensitive to model inaccuracies and measurement noise and biases and can optimize several decision variables at the same time. An adaptive constraint controller integrated into the algorithm regulates the optimization constraints, such as altitude or speed, without requiring and prior knowledge of the autopilot design. The algorithm has a modular structure which allows easy incorporation (or removal) of optimization constraints or decision variables to the optimization problem. An important part of the contribution is the development of analytical tools enabling convergence analysis of the algorithm and the establishment of simple design rules. The fuel-flow minimization and velocity maximization modes of the algorithm are demonstrated on the NASA Dryden B-720 nonlinear flight simulator for the single- and multi-effector optimization cases.

  5. Adaptive critic learning techniques for engine torque and air-fuel ratio control.

    PubMed

    Liu, Derong; Javaherian, Hossein; Kovalenko, Olesia; Huang, Ting

    2008-08-01

    A new approach for engine calibration and control is proposed. In this paper, we present our research results on the implementation of adaptive critic designs for self-learning control of automotive engines. A class of adaptive critic designs that can be classified as (model-free) action-dependent heuristic dynamic programming is used in this research project. The goals of the present learning control design for automotive engines include improved performance, reduced emissions, and maintained optimum performance under various operating conditions. Using the data from a test vehicle with a V8 engine, we developed a neural network model of the engine and neural network controllers based on the idea of approximate dynamic programming to achieve optimal control. We have developed and simulated self-learning neural network controllers for both engine torque (TRQ) and exhaust air-fuel ratio (AFR) control. The goal of TRQ control and AFR control is to track the commanded values. For both control problems, excellent neural network controller transient performance has been achieved.

  6. A Fast, Efficient Domain Adaptation Technique for Cross-Domain Electroencephalography(EEG)-Based Emotion Recognition

    PubMed Central

    Chai, Xin; Wang, Qisong; Zhao, Yongping; Li, Yongqiang; Liu, Dan; Liu, Xin; Bai, Ou

    2017-01-01

    Electroencephalography (EEG)-based emotion recognition is an important element in psychiatric health diagnosis for patients. However, the underlying EEG sensor signals are always non-stationary if they are sampled from different experimental sessions or subjects. This results in the deterioration of the classification performance. Domain adaptation methods offer an effective way to reduce the discrepancy of marginal distribution. However, for EEG sensor signals, both marginal and conditional distributions may be mismatched. In addition, the existing domain adaptation strategies always require a high level of additional computation. To address this problem, a novel strategy named adaptive subspace feature matching (ASFM) is proposed in this paper in order to integrate both the marginal and conditional distributions within a unified framework (without any labeled samples from target subjects). Specifically, we develop a linear transformation function which matches the marginal distributions of the source and target subspaces without a regularization term. This significantly decreases the time complexity of our domain adaptation procedure. As a result, both marginal and conditional distribution discrepancies between the source domain and unlabeled target domain can be reduced, and logistic regression (LR) can be applied to the new source domain in order to train a classifier for use in the target domain, since the aligned source domain follows a distribution which is similar to that of the target domain. We compare our ASFM method with six typical approaches using a public EEG dataset with three affective states: positive, neutral, and negative. Both offline and online evaluations were performed. The subject-to-subject offline experimental results demonstrate that our component achieves a mean accuracy and standard deviation of 80.46% and 6.84%, respectively, as compared with a state-of-the-art method, the subspace alignment auto-encoder (SAAE), which achieves values

  7. Adaptive Switching Technique for Space-Time/Frequency Coded OFDM Systems

    NASA Astrophysics Data System (ADS)

    Change, Namseok; Gil, Gye-Tae; Kang, Joonhyuk; Yu, Gangyoul

    In this letter, a switched transmission technique is presented that can provide the orthogonal frequency division multiplexing (OFDM) systems with additional diversity gain. The space-time block coding (STBC) and space-frequency block coding (SFBC) are considered for the transmission of the OFDM signals. A proper coding scheme is selected based on the estimated normalized delay spread and normalized Doppler spread. The selection criterion is derived empirically. It is shown through computer simulations that the proposed switching technique can improve the bit error rate (BER) performance of an OFDM system when the corresponding wireless channel has some time variation of time selectivity as well as frequency selectivity.

  8. 78 FR 46361 - Trinity Adaptive Management Working Group; Public Meeting, Teleconference and Web-Based Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... Web-Based Meeting AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice. SUMMARY: We, the U.S... Group (TAMWG) and Trinity Management Council (TMC). DATES: Public meeting, Teleconference, and web-based... 299, Douglas City, CA 96024. You may participate in person or by teleconference or web-based meeting...

  9. Adapting Grouping Patterns to Maximize Reading Achievement within an Elementary School Classroom.

    ERIC Educational Resources Information Center

    Wiesendanger, Katherine D.; Birlem, Ellen D.

    The results of a survey of 225 primary school teachers indicate that a high proportion of children in the primary grades are in classrooms that use the basal reader approach. In addition, it is apparent that the vast majority are assigned to either a high, medium, or low group. Once this assignment is made, it becomes difficult for a child to be…

  10. The Influence of Adaptation and Inhibition on the Effects of Onset Asynchrony on Auditory Grouping

    ERIC Educational Resources Information Center

    Holmes, Stephen D.; Roberts, Brian

    2011-01-01

    Onset asynchrony is an important cue for auditory scene analysis. For example, a harmonic of a vowel that begins before the other components contributes less to the perceived phonetic quality. This effect was thought primarily to involve high-level grouping processes, because the contribution can be partly restored by accompanying the leading…

  11. "Depressia" in Post-Katrina New Orleans: Cultural and Contextual Adaptations to Group Interpersonal Psychotherapy

    ERIC Educational Resources Information Center

    Moran, Tracy E.; Larrieu, Julie A.; Zeanah, Paula; Evenson, Amber; Valliere, Jean

    2013-01-01

    Postpartum depression (PPD) affects a significant portion of women and has serious negative short- and long-term consequences for the woman, infant, and family. This article highlights the feasibility and acceptability of group interpersonal psychotherapy (IPT-G), a manualized approach to PPD treatment, with a high risk and underserved sample of…

  12. Small-Group Problem-Based Learning as a Complex Adaptive System

    ERIC Educational Resources Information Center

    Mennin, Stewart

    2007-01-01

    Small-group problem-based learning (PBL) is widely embraced as a method of study in health professions schools and at many different levels of education. Complexity science provides a different lens with which to view and understand the application of this method. It presents new concepts and vocabulary that may be unfamiliar to practitioners of…

  13. "Depressia" in Post-Katrina New Orleans: Cultural and Contextual Adaptations to Group Interpersonal Psychotherapy

    ERIC Educational Resources Information Center

    Moran, Tracy E.; Larrieu, Julie A.; Zeanah, Paula; Evenson, Amber; Valliere, Jean

    2013-01-01

    Postpartum depression (PPD) affects a significant portion of women and has serious negative short- and long-term consequences for the woman, infant, and family. This article highlights the feasibility and acceptability of group interpersonal psychotherapy (IPT-G), a manualized approach to PPD treatment, with a high risk and underserved sample of…

  14. Adaptive enhancement and visualization techniques for 3D THz images of breast cancer tumors

    NASA Astrophysics Data System (ADS)

    Wu, Yuhao; Bowman, Tyler; Gauch, John; El-Shenawee, Magda

    2016-03-01

    This paper evaluates image enhancement and visualization techniques for pulsed terahertz (THz) images of tissue samples. Specifically, our research objective is to effectively differentiate between heterogeneous regions of breast tissues that contain tumors diagnosed as triple negative infiltrating ductal carcinoma (IDC). Tissue slices and blocks of varying thicknesses were prepared and scanned using our lab's THz pulsed imaging system. One of the challenges we have encountered in visualizing the obtained images and differentiating between healthy and cancerous regions of the tissues is that most THz images have a low level of details and narrow contrast, making it difficult to accurately identify and visualize the margins around the IDC. To overcome this problem, we have applied and evaluated a number of image processing techniques to the scanned 3D THz images. In particular, we employed various spatial filtering and intensity transformation techniques to emphasize the small details in the images and adjust the image contrast. For each of these methods, we investigated how varying filter sizes and parameters affect the amount of enhancement applied to the images. Our experimentation shows that several image processing techniques are effective in producing THz images of breast tissue samples that contain distinguishable details, making further segmentation of the different image regions promising.

  15. Hyperefficient PrP Sc amplification of mouse-adapted BSE and scrapie strain by protein misfolding cyclic amplification technique.

    PubMed

    Fujihara, Aiko; Atarashi, Ryuichiro; Fuse, Takayuki; Ubagai, Kaori; Nakagaki, Takehiro; Yamaguchi, Naohiro; Ishibashi, Daisuke; Katamine, Shigeru; Nishida, Noriyuki

    2009-05-01

    Abnormal forms of prion protein (PrP(Sc)) accumulate via structural conversion of normal PrP (PrP(C)) in the progression of transmissible spongiform encephalopathy. Under cell-free conditions, the process can be efficiently replicated using in vitro PrP(Sc) amplification methods, including protein misfolding cyclic amplification. These methods enable ultrasensitive detection of PrP(Sc); however, there remain difficulties in utilizing them in practice. For example, to date, several rounds of protein misfolding cyclic amplification have been necessary to reach maximal sensitivity, which not only take several weeks, but also result in an increased risk of contamination. In this study, we sought to further promote the rate of PrP(Sc) amplification in the protein misfolding cyclic amplification technique using mouse transmissible spongiform encephalopathy models infected with either mouse-adapted bovine spongiform encephalopathy or mouse-adapted scrapie, Chandler strain. Here, we demonstrate that appropriate regulation of sonication dramatically accelerates PrP(Sc) amplification in both strains. In fact, we reached maximum sensitivity, allowing the ultrasensitive detection of < 1 LD(50) of PrP(Sc) in the diluted brain homogenates, after only one or two reaction rounds, and in addition, we detected PrP(Sc) in the plasma of mouse-adapted bovine spongiform encephalopathy-infected mice. We believe that these results will advance the establishment of a fast, ultrasensitive diagnostic test for transmissible spongiform encephalopathies.

  16. Study on adaptive thresholding technique of image denoising based on wavelet transform

    NASA Astrophysics Data System (ADS)

    Zhu, Xi'an; Xie, Xiao

    2010-12-01

    It is studied in the paper that an adaptive soft and hard thresholding image denoising method, in which image pyramid decomposing is realized by wavelet transform, and the mean value, mid-value and root mean square value of different sub bands are calculated as thresholding. The image is added into different kinds and different intensities noise, and processed by different wavelet decomposing levels and thresholding selected algorithms, the total 27 kinds of thresholding combination schemes are completed in the research process. The SNR (signal noise ratio) and PSNR (peak signal noise ratio) of denoised image are compared and analyzed and benefited results are achieved. Furthermore, the algorithm in reference is realized by MATLAB program, the results of reference are compared with that of the paper to demonstrate the significance and correctness of the results in the paper.

  17. Study on adaptive thresholding technique of image denoising based on wavelet transform

    NASA Astrophysics Data System (ADS)

    Zhu, Xi'an; Xie, Xiao

    2011-05-01

    It is studied in the paper that an adaptive soft and hard thresholding image denoising method, in which image pyramid decomposing is realized by wavelet transform, and the mean value, mid-value and root mean square value of different sub bands are calculated as thresholding. The image is added into different kinds and different intensities noise, and processed by different wavelet decomposing levels and thresholding selected algorithms, the total 27 kinds of thresholding combination schemes are completed in the research process. The SNR (signal noise ratio) and PSNR (peak signal noise ratio) of denoised image are compared and analyzed and benefited results are achieved. Furthermore, the algorithm in reference is realized by MATLAB program, the results of reference are compared with that of the paper to demonstrate the significance and correctness of the results in the paper.

  18. Automatic ultrasonic imaging system with adaptive-learning-network signal-processing techniques

    SciTech Connect

    O'Brien, L.J.; Aravanis, N.A.; Gouge, J.R. Jr.; Mucciardi, A.N.; Lemon, D.K.; Skorpik, J.R.

    1982-04-01

    A conventional pulse-echo imaging system has been modified to operate with a linear ultrasonic array and associated digital electronics to collect data from a series of defects fabricated in aircraft quality steel blocks. A thorough analysis of the defect responses recorded with this modified system has shown that considerable improvements over conventional imaging approaches can be obtained in the crucial areas of defect detection and characterization. A combination of advanced signal processing concepts with the Adaptive Learning Network (ALN) methodology forms the basis for these improvements. Use of established signal processing algorithms such as temporal and spatial beam-forming in concert with a sophisticated detector has provided a reliable defect detection scheme which can be implemented in a microprocessor-based system to operate in an automatic mode.

  19. Urban Infrastructure Monitoring with a Spatially Adaptive Multi-Looking InSAR Technique

    NASA Astrophysics Data System (ADS)

    Sharma, Jayanti; Eppler, Jayson; Busler, Jennifer

    2015-05-01

    Surface displacements for urban infrastructure monitoring are derived using Interferometric Synthetic Aperture Radar (InSAR). The analysis uses a novel InSAR method, Homogenous Distributed Scatterer (HDS)-InSAR, that exploits both persistent point and coherent distributed scatterers using adaptive multi-looking of statistically homogenous pixel neighbourhoods. An unwrapped phase model incorporating meteorological data enables separation of temperature-correlated displacement from potentially hazardous long-term trends. Results are presented over the Canadian cities of Regina, Winnipeg and Montreal using RADARSAT-2 and TerraSAR-X data. The new combination of HDS-InSAR and the extended phase model permits large areas of infrastructure to be remotely monitored on a regular basis and enables a more targeted monitoring process to help identify infrastructure at greatest risk for damage.

  20. Adaptation of the cellscan technique for the SCM test in breast cancer.

    PubMed

    Rahmani, H; Deutsch, M; Ron, I; Gerbat, S; Tirosh, R; Weinreb, A; Chaitchik, S; Lalchuk, S

    1996-09-01

    The value of the SCM (Structuredness of Cytoplasmic Matrix) cancer test, a procedure based on the detection of differences in lymphocyte activation in the presence and absence of cancer, has remained controversial, with inconsistent results having been reported among investigators. The Cellscan, a high-precision static cytometer system, has been designed to perform the SCM test; the apparatus facilitates the polarisation measurements and can examine cells which have been separated by simpler procedures than were originally described. In this study, using methods and diagnostic criteria adapted for the Cellscan system in a hospital environment, the SCM test correctly classified over 90% (76/80) of patients with breast cancer and differentiated over 90% (72/73) of individuals without cancer.